Operator Manual Series GEM OEM Industrial Lasers GEM

Operators ManualGEM Series OEM/Industrial LasersGEM-100 Air Cooled

1280 Blue Hills AvenueBloomfield, Connecticut 06002-1301Telephone: (800) 367-7890

GEM-100 Air Cooled Laser Operators Manual

This document is copyrighted with all rights reserved. Under the copyrightlaws, this document may not be copied in whole or in part or reproduced inany other media without the express written permission of Coherent, Inc.Permitted copies must carry the same proprietary and copyright notices aswere affixed to the original. This exception does not allow copies to bemade for others, whether or not sold, but all the material purchased maybe sold, given or loaned to another person. Under the law, copyingincludes translation into another language.

Coherent, Coherent/DEOS, the Coherent Logo, GEM-25, GEM-30,GEM-50, GEM-60, GEM-100, GEM-200PC, GEM-Q400. GEM-Q3000,and PC-1 Controller are registered trademarks of Coherent, Inc.DOWFROST, DOWTHERM, and DOWCAL are registered trademarks ofThe Dow Chemical Company. UCARTHERM is a registered trademark ofUnion Carbide Corporation. Pipe Saver is a registered trademark ofVirginia KMP Corp. Teflon is a registered trademark of E. I. du Pont deNemours and Company.

Every effort has been made to ensure that the data given in this documentis accurate. The information, figures, tables, specifications and schematicscontained herein are subject to change without notice. Coherent makes nowarranty or representation, either expressed or implied with respect to thisdocument. In no event will Coherent be liable for any direct, indirect,special, incidental or consequential damages resulting from any defects inits documentation.

Technical Support

In the US:

Should you experience any difficulties with your laser or need anytechnical information, please visit our web site www.coherentinc.com.Additional support can be obtained by contacting our Technical SupportHotline at 800-367-7890 or E-mail ([email protected]).Telephone coverage is available Monday through Friday (except U.S.holidays). If you call outside our office hours, your call will be taken by ouranswering system and will be returned when the office reopens.

If there are technical difficulties with your laser that cannot be resolved bysupport mechanisms outlined above, please E-mail or telephone CoherentTechnical Support with a description of the problem and the correctivesteps attempted. When communicating with our Technical Support Group,through the web or telephone, the model and Laser Head serial number ofyour laser system will be required by the Support Engineer responding toyour request.

Outside the US:

If you are located outside the US visit our web site for technical assistanceor contact, by phone, our local Service Representative. Representativephone numbers and addresses can be found on the Coherent web site,www.coherentinc.com.

Coherent provides telephone and web technical assistance as a service toits customers and assumes no liability thereby for any injury or damagethat may occur contemporaneous with such services. These supportservices do not affect, under any circumstances, the terms of any warrantyagreement between Coherent and the buyer. Operation of any Coherentlaser with any of its interlocks defeated is always at the operator's own risk.

ii

Table of Contents

TABLE OF CONTENTS

Preface ........................................................................................................................... viiU.S. Export Control Laws Compliance ......................................................................... viiNotice Concerning Regulatory Status of GEM Series Lasers ....................................... viiNotice Concerning Warranty ......................................................................................... viiSymbols Used in This Manual...................................................................................... viii

Section One: Description and Specifications........................................... 1-1Introduction................................................................................................................... 1-1Purpose of This Manual ................................................................................................ 1-1Variations in Hardware Configuration ......................................................................... 1-2

RF Cable Lengths ................................................................................................ 1-2Specifications and Input Requirements ........................................................................ 1-2Hardware Overview...................................................................................................... 1-3

DC Input Power ................................................................................................... 1-3Cooling Requirements .................................................................................................. 1-3

Comparison of Air-Cooling and Liquid-Cooling (Reference) ............................ 1-3Laser Head .................................................................................................................... 1-4RF Power Supply .......................................................................................................... 1-4

Compatibility and Interchangeability .................................................................. 1-5

Section Two: Laser Safety .................................................................................. 2-1Optical Safety ............................................................................................................... 2-1Electrical Safety ............................................................................................................ 2-3

Laser Head ........................................................................................................... 2-3Laser Safety Requirements ........................................................................................... 2-3

Safety Interlocks .................................................................................................. 2-4Radiated Emission Compliance .................................................................................... 2-4

Interference Potential of the System.................................................................... 2-4Compliance to Standards Relevant to CE Mark ........................................................... 2-4Location of Safety Labels ............................................................................................. 2-5Certifications of Compliance ........................................................................................ 2-8

Section Three: Utility Requirements and System Installation..... 3-1Unpacking and Inspection ............................................................................................ 3-1

Verifying Delivery ............................................................................................... 3-1Checking Delivered Items ................................................................................... 3-1

Safety Issues in Laser Installation ................................................................................ 3-2Mechanical Mounting ................................................................................................... 3-2

Mounting Considerations for Laser Heads .......................................................... 3-5Mounting Considerations for the RF Power Supply............................................ 3-5Ambient Air Cleanliness...................................................................................... 3-5

Air Cooling ................................................................................................................... 3-5Air Flow............................................................................................................... 3-6

iii


Signal Interface .................................................................................................... 3-6Over Temperature Interlock Switch .................................................................... 3-6DC Power Relay .................................................................................................. 3-6

Electrical Power Connection ........................................................................................ 3-7DC Power Supply Requirements ......................................................................... 3-8

Control Signal Connection............................................................................................ 3-8RF Power Supply Connection....................................................................................... 3-8

Coaxial Cable....................................................................................................... 3-8Cable Connections and Torque............................................................................ 3-9

Section Four: Laser Operation ........................................................................ 4-1Signal Interface Connectors.......................................................................................... 4-1Operating Modes........................................................................................................... 4-1

Typical Waveform ............................................................................................... 4-1CW Mode............................................................................................................. 4-1Gated CW Mode .................................................................................................. 4-3Variable Output Power Capability; Pulsewidth Variation................................... 4-3

Optical Pulse Shape .................................................................................... 4-3Complex Modulation Waveforms ....................................................................... 4-4

Varying the Pulsewidth............................................................................... 4-4Protection from Unacceptable Inputs ......................................................... 4-4

Turning On the Laser .................................................................................................... 4-4Electronic Control......................................................................................................... 4-5

Electronic Signals Required to Turn On the Laser .............................................. 4-5Modulation Select ....................................................................................... 4-5Start-up Sequence ....................................................................................... 4-5

Response Times of Laser to Modulation, and Power Supply Enable.................. 4-6Signals Used for Fault Detection ......................................................................... 4-6VSWR Faults During Initial Turn-on .................................................................. 4-7

Section Five: Maintenance and Troubleshooting ................................. 5-1Maintenance.................................................................................................................. 5-1

Cleanliness of Output Optical Element ............................................................... 5-1Troubleshooting ............................................................................................................ 5-1

Connectors and Cables......................................................................................... 5-1DC Power and Voltage ........................................................................................ 5-2Control Inputs ...................................................................................................... 5-2VSWR Fault Indicator ......................................................................................... 5-2Over Temperature Shutdown............................................................................... 5-2CW Mode............................................................................................................. 5-2Visualizing ........................................................................................................... 5-3Voltages ............................................................................................................... 5-3Output Beam ........................................................................................................ 5-3

Parts List ........................................................................................................................ A-1

iv

Table of Contents

Warranty.........................................................................................................................B-1GEM Series Laser Warranty.........................................................................................B-1Conditions of Warranty ................................................................................................B-1Responsibilities of the Buyer ........................................................................................B-1Limitations of Warranty................................................................................................B-2

Glossary ............................................................................................................... Glossary-1

Packing Procedure ....................................................................................................C-1For Liquid Cooled Lasers/ RF Power Supplies ............................................................C-1For All Laser Heads ......................................................................................................C-1For All RF Power Supplies ...........................................................................................C-2Shipping Instructions ....................................................................................................C-2RMA Form Instructions................................................................................................C-2

Index ........................................................................................................................... Index-1

v


LIST OF ILLUSTRATIONS

1-1 GEM-100 Air Cooled Laser System.......................................................................... 1-11-2 GEM-100 Air Cooled Laser Head ............................................................................. 1-41-3 D-1000 Air Cooled RF Power Supply ....................................................................... 1-5

2-1 Location of Safety Labels .......................................................................................... 2-52-2 Declaration of Conformity......................................................................................... 2-8

3-1 GEM-100 Air Cooled Laser Head Dimensions ......................................................... 3-33-2 D-1000 W Air Cooled RF Power Supply Dimensions .............................................. 3-43-3 Electrical Connections to D-1000 RF Power Supply ................................................ 3-7

4-1 RF Input Waveform and Laser Output Waveform .................................................... 4-34-2 Fault Detection Circuit............................................................................................... 4-6

5-1 GEM-100 Voltage Chart............................................................................................ 5-4

LIST OF TABLES

1-1 Specifications and Input Requirements for GEM-100 Lasers ................................... 1-6

4-1 Signal Interface Description and Connector Pinout .................................................. 4-2

A-1 GEM-100 (100 Watts) Laser System - Typical Configurations ............................... A-1A-2 GEM-100 (100 Watts) Laser Component Part Numbers.......................................... A-1

vi

Preface

Preface This is the Operators Manual for the GEM-100 Air CooledOEM/Industrial carbon dioxide (CO2) lasers manufactured byCoherent/DEOS®. These lasers are OEM systems, they aredesigned as components which are to be inserted by the originalequipment manufacturer (OEM) prior to delivery to the end user. Itis strongly recommended that the user read Section Two, LaserSafety, before operating the laser.

Caution use of controls or adjustments or performance ofprocedures other than those specified in this manual may resultin hazardous radiation exposure.

U.S. Export Control Laws Compliance

It is the policy of Coherent/DEOS to comply strictly with the U.S.export control laws.

Export and re-export of lasers manufactured by Coherent/DEOS aresubject to the U.S. Export Administration Regulations administeredby the Department of Commerce, Bureau of Export Administration.

The applicable restrictions vary depending on the specific productinvolved, intended application, and the product destination. In somecases, an individual validated export license is required from theU.S. Department of Commerce prior to resale or re-export of certainproducts. If you are uncertain about the obligations imposed by U.S.law, obtain clarification from Coherent/DEOS.

Notice Concerning Regulatory Status of GEM Series Lasers

This laser component does not include all safety features that arerequired by the United States Food and Drug Administration (FDA),Center for Devices and Radiological Health (CDRH) in lasersystems sold to end users. It is sold solely to qualified manufacturerswho in their end product, supply interlocks, indicators, and otherrequired safety features, in full compliance with 21 CFR 1040,Subchapter J and/or other applicable national and local regulations.

Notice Concerning Warranty

Operation or handling of this laser component, inconsistent with thismanual, may void the warranty.

vii


Symbols Used in This Manual

This symbol is intended to alert the operator to the presence ofdangerous voltages associated with the laser that may be of suffi-cient magnitude to constitute a risk of electric shock.

This symbol is intended to alert the operator to the presence ofimportant operating and maintenance instructions.

This symbol is intended to alert the operator to the danger ofexposure to hazardous visible and invisible laser radiation.

viii

Description and Specifications

SECTION ONE: DESCRIPTION AND SPECIFICATIONS

Introduction In this section, specifications and characteristics of the GEM-100laser will be discussed. Characteristics to be discussed includemechanical, thermal, electrical, and optical interfaces; and environ-mental requirements and limitations.

The GEM-100 laser is a sealed-off, RF excited CO2 laser capable ofCW or modulated operation. From the laser safety point of view, thislaser is considered a component and must be integrated into a systemby a qualified original equipment manufacturer (OEM) prior todelivery to the end user. See Section Two for a complete discussionof laser safety issues.

Purpose of This Manual

This manual is designed to assist the original equipment manufac-turer during the integration or the GEM-100 OEM laser. It containsinformation on the performance and operation of the laser as well asinstallation and control methods.

Figure 1-1. GEM-100 Air Cooled Laser System

1 - 1


Variations in Hardware Configuration

For each GEM-100 laser there are a number of variations in theconfiguration of hardware delivered to customers. These variationsare due to the following factors:

Customers can also select among several options in the lengthof the RF power cable which connects the RF power supply tothe laser head. These optional extender cables, if selected bythe customer, are added to the short RF cable which comeswith every GEM-100.

Do not operate any GEM-100 laser head with any RF powersupply other than the Coherent/DEOS® Model D-1000 RFpower supply. Any operation of an GEM-100 laser head with anRF power supply other than the Model D-1000 will void theCoherent/DEOS® warranty. Do not under any circumstancesmodify the RF cable.

RF Cable Lengths There are several options regarding the length of the cable whichconnects the RF power supply to the laser head. The RF cableoptions are described in the section entitled RF Power SupplyConnection. For part numbers please check the section titled PartsList in this manual.

Specifications and Input Requirements

Figure 1-1 provides specifications, and requirements for powerinputs, for the Model GEM-100 laser.

Figure 1-1 illustrates the baseline configurations (i.e., without anyoptional hardware additions or deletions) of the GEM-100 laser.Each laser system consists of a laser head assembly, a radiofrequency (RF) power supply, and a coaxial cable for connecting theRF power supply to the laser head. The RF power supply converts48-50 VDC, ≤50 A power to radio frequency power. Connection ofthe customer-supplied DC power supply to the Coherent/DEOS®supplied Model D-1000 RF power supply is through a barrier stripwith screw terminals on the RF power supply. The barrier stripincludes terminals for connection of wires for remote voltagesensing. Such sensing is recommended to better control the voltageat the input to the RF power supply.

1 - 2


Hardware Overview

The GEM-100 laser is a waveguide carbon dioxide (CO2) laser. RFelectric fields provided by the RF power supply are delivered to thelaser head through the special connecting coaxial cable. The RFelectrical field excites the CO2 gas mixture. The standard configura-tion of this laser operates at a wavelength near 10.6 µm in theinfrared region of the electromagnetic spectrum.

DC Input Power DC input power is provided by the user through customer-suppliedbus wiring, which goes to the RF power supply. The RF powersupply converts this DC electrical power into RF power which isused to excite the gas in the laser head.

Cooling Requirements

Total heat dissipation for the laser head and RF power supply isspecified in Table 1-1. The laser head typically dissipates 1200 Wfrom its base surface while the RF power supply typically dissipates800 W, for a total typical heat dissipation of 2000 W (maximumtotal heat dissipation is 2400 W). The GEM-100 must be providedadequate cooling to keep the laser operating temperature withinacceptable limits. The cooling method that is used must not inducestresses that will result in misalignment of the laser resonator. Theheat sinks which are included in the air cooled GEM-100 aredesigned so that the assembled structure remains free of excessivestress. Installation requirements related to cooling of the air-coolingversion of the GEM-100 laser are discussed in detail in SectionThree in the subsection entitled Air Cooling.

Comparison of Air-Cooling and Liquid-Cooling (Reference)

Air cooling has some distinct advantages relative to liquid cooling.It is low in cost, low in complexity, and has low service requirements.The air-cooling option is easier to install. Liquid-cooling, on theother hand, can yield the most compact arrangement and is gener-ally more suitable for applications in which the ambient air temper-ature exceeds 40ºC and/or the ambient air is heavily laden withparticulates. One should also consider if condensable vapors arepresent and take suitable measures to purge sensitive areas such asoptical surfaces with a suitable gas. It is generally easier to make ahermetically sealed system using a liquid-cooling approach ratherthan an air-cooling one. Applications which require the highestprocess stability will also yield better results if the temperature iscontrolled with a liquid based cooling system.

1 - 3


To avoid damage to the laser head and the RF power supply,never operate the laser without adequate air cooling.

Laser Head The laser head takes RF input power and converts some of it to laserradiation. The rest of the RF input power is exhausted as waste heat.For the GEM-100 air cooled laser, the waste heat is exhausted intothe ambient air. The laser head consists of the folded opticalwaveguide resonator, the all-metal gas envelope structure, the RFmatching network, and a type-N RF power connector. Infrared laserradiation is emitted from the optical aperture. Pictures and dimen-sions drawings for the GEM-100 air cooled laser is shown inFigure 1-2 and Figure 3-1.

RF Power Supply The Model D-1000 RF power supply converts DC input power to RFenergy which is sent through the RF cable to the laser head. Heatfrom the RF power supply is exhausted into the surrounding air. Amale 15-pin D type connector built into the RF power supply, is usedto control the laser system. All the user interfaces (DC power andsignal interface) are on one panel of the RF power supply.

Figure 1-2. GEM-100 Air Cooled Laser Head

1 - 4


The GEM-100 laser head requires approximately 1000 W of CW RFinput power in CW Mode. A picture of the 1000 W RF power supply(D-1000) for the GEM-100 air cooled laser is shown in Figure 1-3.The corresponding dimensions is shown in Figure 3-2.

Compatibility and Interchangeability

Any two GEM-100 laser heads can be interchanged (except as notedin the section entitled Mounting Considerations for Laser Heads).Similarly, any two GEM-100 RF power supplies can be inter-changed.

To avoid possible damage to the laser head and the RF powersupply, use only the Model D-1000 RF power supply with theGEM-100 laser head.

Figure 1-3. D-1000 Air Cooled RF Power Supply

1 - 5


Table 1-1. Specifications and Input Requirements for GEM-100 Lasers

CHARACTERISTIC SPECIFIED VALUE COMMENTS

Wavelength 10.6 µm Lines near 10P20 line of 12C16O2

1CW Output Power ≥100 W De-rate power by 1% per ºC for laser head temperatures above 25ºC.

Power Stability < ±5%

Mode >98% TEM00

Beam Size 3.8 ± 0.4 mm At 1/e2 diameter at exit aperture

Beam Divergence <5 mrad At 1/e2 diameter in the far field

1Beam Quality M 2<1.3

Polarization >100 to 1 fixed linear

1Modulation TTL up to 25 kHz

Weight of Laser Head 26 lbs (11.8 kg) Nominal values

Weight of Power Supply 18 lbs (8.2 kg) Nominal values

Input voltage 48-50 VDC Remote sensing at power input terminalson RF power supply recommended.

Input DC current ≤49 A

Ambient Air Temperature 15ºC to 40ºC

Altitude <6,500 ft. (2,000 m)

Humidity Non-condensing

1 Those characteristics are guaranteed; all other stated characteristics are typical.Specifications are subject to change without notice.

1 - 6

Laser Safety

SECTION TWO: LASER SAFETY

Optical Safety The GEM-100 laser has undergone extensive testing to ensure that,with proper usage, it is a safe and reliable device.

Laser light, because of its special properties, poses safety hazardsnot associated with light from other sources. The safe use of lasersrequires that all laser users and everyone near a laser be aware of thedangers involved in laser operation.

Direct eye contact with the output beam from the laser will causeserious damage and may cause blindness.

All personnel in the same room as the laser or anyone who may beexposed to the laser beam should be informed that a laser is in oper-ation. All personnel must wear laser safety glasses which protectagainst the wavelengths in use.

Note: There is no visible indication at the GEM-100 laser headthat it is operating.

Exercise caution to protect against specular reflections sincereflections at the GEM-100 laser wavelength are invisible.

Eye safety is a great concern when using a high-power laser such asthe GEM-100 laser. There are often many secondary beams presentat various angles near the laser. These beams are specular reflectionsof the main beam from polished surfaces. While weaker than themain beam, such beams may still be sufficiently intense to cause eyedamage.

Laser beams are also powerful enough to burn skin, clothing orpaint. They can ignite volatile substances such as alcohol, gasoline,ether, and other solvents and can damage the light-sensitiveelements in video cameras, photomultipliers, and photodiodes.

2 - 1


Coherent provides the following recommendations to promote thesafe use of the GEM-100 laser. Operators are advised to adhere tothese recommendations and employ sound laser safety practices atall times.

Use protective eyewear when operating the laser and guardagainst inadvertent exposure to skin or clothing. Selecteyewear which is suitable for use with the wavelengths andradiation intensity that the laser emits. Refer to the Guide forSelection of Laser Eye Protection, Laser Institute of America(5th Edition), 2000.

Do not remove the protective covering over the beam path.During normal operation, internal reflections are confinedwithin the laser head and pose no safety hazard.

Never look directly into the laser output port when the poweris on.

Set up the laser and all optical components used with the laseraway from eye level. Provide enclosures for the laser beam.

Use the laser in a room with access controlled by door inter-locks. Post warning signs. When operating the laser, limitaccess to the area to individuals who are trained in laser safety.

Avoid operating the laser in a darkened environment.

Do not use the laser in the presence of flammables, explosives,or volatile solvents such as alcohol, gasoline, or ether.

For additional information on laser safety, refer to the followingpublications:

American National Standard for the Safe Use of Lasers,Z136.1-2000, American National Standards Institute, 2000.

Performance Standard for Laser Products. FDA., (FR-40)(148): 32252-32265. Department of Health, Education andHuman Service Bureau of Radiological Health, July 31, 1974.

Laser Safety Guide, Laser Institute of America. (10th Edition).Orlando, FL 2000.

Guide for Selection of Laser Eye Protection, Laser Institute ofAmerica (5th Edition), 2000.

D. Sliney and M. Wolbarsht. Safety with Lasers and OtherOptical Sources,. Plenum Publishing Company, New York,N.Y., 1980.

2 - 2

Laser Safety

Many of these documents on Laser Safety are available throughLaser Institute of America, 13501 Ingenuity Drive, Suite 128,Orlando, CA 32826. Phone 800-345-2737 and on their web sitewww.laserinstitute.org. Regulatory information if available at theirCDRH web site www.fda.gov/cdrh.

Electrical Safety The GEM-100 RF power supply requires only 48 VDC to 50 VDCinput voltage. These voltages can be lethal. Every portion of theelectrical system should be treated as if it is at a dangerous voltagelevel.

Laser Head High voltages are present in the laser head when the power is on.There are no serviceable parts or optics within the laser head. Do notremove any covers or make any adjustments to any screw.

Laser Safety Requirements

This laser does not conform to the United States or Foreign Govern-ment requirements for laser safety. In the United States, it is theresponsibility of the buyer that the product sold to the end usercomplies with all laser safety requirements prior to resell. Theselaser safety requirements are contained in 21 CFR, Sub Chapter Jand are administered by the Center for Devices and RadiologicalHealth.

The text of this federal law is available from the U.S. GovernmentPrinting Office Bookstore located in most major cities in the U.S. aswell as Washington, D.C. A report detailing how the laser productcomplies with the Federal law is required before the product isshipped. The form of this report is covered in a pamphlet entitled:Guide for Preparing Product Reports for Lasers and ProductsContaining Lasers, Sept. 1995:

U.S. Department of Health and Human ServicesPublic Health ServiceFood and Drug AdministrationCenter for Devices and Radiological HealthDivision of Small Manufactures AssistanceRockville, Md 20857Voice phone: 1-800-638-2041Web site: http://www.fda.gov/cdrh

For jurisdictions outside of the United States, it is the responsibilityof the buyer of this laser device to ensure that it meets the local lasersafety requirements.

2 - 3


Safety Interlocks The RF power supply and laser head covers are not interlocked.These covers should never be removed. There are no user service-able components inside.

Use of controls or adjustments, or performance of proceduresother than those specified herein, may result in hazardous radi-ation exposure.

Radiated Emission Compliance

The GEM-100 laser has been tested and verified that it is in compli-ance with the radiated emission limits of FCC rules contained in 47CFR Part 18 Subpart C for industrial, scientific, and medical equip-ment.

The following information to the user is provided in compliancewith United States Government requirements contained in 47 CFR18.213.

Interference Potential of the System

In our testing in a variety of laboratory and industrial settings, wehave not found any significant electrical interference that can betraced to the GEM-100 laser. The GEM-100 laser is excited by anRF power supply operating at 100 MHz. The RF power is modulatedat the same pulse width and pulse period selected in operating thelaser. If the GEM-100 laser is determined to be the source of inter-ference with other equipment, use shielded cables, including controlcables, to the unit experiencing the interference problem. The shieldshould be grounded.

Compliance to Standards Relevant to CE Mark

The GEM-100 laser units are components and thus the system inte-grator is responsible for meeting the applicable standards for CEmark. As part of the testing program, the GEM-100 laser with theoptional DC power supply has been shown to be compliant with therelevant requirements of the electromagnetic compatibility direc-tive. The tests shows compliance with radiated emissions andconducted line emissions (EN 55011 (1991) Class A, Group 2), elec-trostatic discharge (EN 61000-4-2 (1995) Level 3 air, Level 2contact), radiated immunity (EN 61000-4-3 (1997) Level 3/ENV50204 (1995)/ ENV 50140 (1993), Level 3, Criteria A), electricalfast transients (EN 61000-4-4 (1995) Level 3), and conducted RFimmunity (EN 61000-4-6 (1996)/ENV 50141 (1993) Level 3).

2 - 4

Laser Safety

Compliance to the applicable standards for a particular laser systemincorporating the GEM-100 laser unit must be demonstrated by themanufacturer. By testing the GEM-100 laser system, it is shown thatthis step is possible. The primary issue for the system integrator is toshow compliance with specific covers, routing of the electricalcables, laser safety standards, as well as other applicable standards.

Location of Safety Labels

Refer to Figure 2-1 for a description and location of all requiredsafety labels. These include warning labels indicating removable ordisplaceable protective housings, apertures through which laserradiation is emitted and labels of certification and identification[CFR 1040.10(g), CFR 1040.2, and CFR 1010.3/EN60825-1,Clause 5].

Figure 2-1. Location of Safety Labels (Sheet 1 of 3)

24

35 6

2 - 5


1. IDENTIFICATION LABEL

2. DANGER OF LASER RADIATION LABEL


7

2 - 6

Laser Safety

3. AVOID EXPOSURE TO INVISIBLE RADIATION FROM APERTURE LABEL

4. APERTURE LABEL

5. ALERT TO INVISIBLE LASER RADIATION LABEL

6. CE COMPLIANCE LABEL

7. ELECTRICAL WARNING SYMBOL LABEL


2 - 7


2 - 8

Certifications of Compliance

The following pages contain certifications of compliance ofGEM-100 lasers and associated documentation with various regula-tions and standards.

Figure 2-2. Declaration of Conformity

Utility Requirements and System Installation

SECTION THREE: UTILITY REQUIREMENTS AND SYSTEM INSTALLATION

This section covers unpacking and installation of your GEM-100laser. Detailed operating instructions are given in Section Four:Laser Operation.

Unpacking and Inspection

Before unpacking the laser components, inspect the shipping cartonfor evidence of rough handling, and note any damage. If damage tothe shipping carton is evident, request the carriers agent be presentwhen the unit is unpacked. Inform the shipping carrier andCoherent/DEOS® of any evidence of damage in shipment. TheBuyer and its shipping carrier is responsible for any damage whichoccurs during shipment.

Verifying Delivery The shipping container contains the following:

Laser head;

RF power supply;

RF cable;

Final Test Sheet;

a copy of this Operating Manual.

If any of these items are missing, report this to Coherent/DEOS®immediately.

Checking Delivered Items

Verify each of the following:

The delivered laser head model is that same as the one ordered.

The delivered RF power supply is compatible with the deliv-ered laser head, i.e., the laser head is a Model GEM-100 andthe power supply is a Model D-1000.

Verify that the received RF cable is the one that was ordered.

If there is any discrepancy noted, contact Coherent/DEOS® imme-diately.

3 - 1


We recommend that you save the shipping box and packing mate-rials, since these will be useful should you need to ship the laser backto Coherent/DEOS®.

Safety Issues in Laser Installation

Installation of the GEM-100 laser must be such as to comply with allapplicable electrical safety and laser safety laws and regulations.Review Section Two on Laser Safety for important informationrelating to safety.

The negative (return) side of the DC input connection to theGEM-100 RF power supply is connected internally to the chassis.The user must assure that the system into which the GEM-100 isbuilt protects against the possibility that the GEM-100 laser head orRF power supply chassis could be at a hazardous voltage and thatpersonnel could be exposed to these voltages.

To avoid potentially fatal electrical shock hazards from electricalequipment, be sure to follow all applicable electrical codes such as(in the U.S.) the National Electrical Code.

Be sure the laser is properly secured to avoid the possibility of thelaser moving unexpectedly during operation, thus creating ahazardous condition. The location of the output beam of theGEM-100 laser head is shown in Table 3-1. The laser output isemitted from the aperture shown in the referenced figures and prop-agates within a full cone angle up to 5º. Be sure that the acceptanceangle of the system aperture intercepts all of the output of the laser.

It is also extremely important to understand the direction, diver-gence, and magnitude of all reflections that will occur from opticalsurfaces. Infrared (IR) beams such as those from GEM-100 laserscan also be located with commercially available IR screens such asthose produced by Macken Instruments, Inc. [tel. (707) 566-2110].Coherent/DEOS® recommends that all beam propagation paths beenclosed and that personnel operating the laser be qualified opticaltechnicians who are familiar with this type of hardware.

Mechanical Mounting

The dimensions for the GEM-100 laser head is shown in Figure 3-1.The dimensions for the D-1000 RF power supply is shown inFigure 3-2. Mechanical mounting of the GEM-100 laser head mustbe such that the laser head is not distorted or stressed in any way, oroptical alignment and power stability could be adversely affected.

3 - 2


Dimensions are in inches [mm]

Figure 3-1. GEM-100 Air Cooled Laser Head Dimensions

3 - 3


Dimensions are in inches [mm]

Figure 3-2. D-1000 W Air Cooled RF Power Supply Dimensions

3 - 4


Mounting Considerations for Laser Heads

Certain aspects of specific customer applications may precludeabsolute interchangeability of laser heads. For example, for certainapplications, the sensitivity of the application to optical beampointing errors may require optical realignment after the laser headis replaced in the customers integrated system. Depending on themethod of mounting and the sensitivity of the integrated customersystem to beam pointing errors, even removing a laser head from thecustomers system, then replacing the same laser head back into thecustomers system may require optical realignment. ConsultCoherent/DEOS® if there is any question about such interchange-ability issues.

Coherent/DEOS recommends use of the optional brackets (partnumber #1400-12-0009 set of 4) that are designed for safe mountingof the laser without inducing any stress onto the laser. In any casetake care not to induce stress onto the laser head as optical mis-align-ment can occur which would require the laser to be returned toCoherent/DEOS® for service.

Mounting Considerations for the RF Power Supply

The main considerations in the mounting of the RF power supply arethat it be near enough to the laser head that the available RF cable,including strain relief, spans the required distance.

Ambient Air Cleanliness

GEM-100 laser heads are designed for use in a dust free or nearlydust free environment. They should be installed in a protectivehousing which prevents dust or debris from contaminating theoptical output window. Do not turn on the laser if there is water, dust,or dirt on the output element, damage to the coating on this opticalelement may occur. To prevent such optical damage never allow theoutput window to become contaminated.

The Coherent/DEOS® warranty covers defects in material andworkmanship relating to the output optical element, but thiswarranty does not cover damage to the external output opticalsurface which is the result of contamination of the surface, or abra-sion of the surface.

Air Cooling The GEM-100 air cooled laser incorporates heat sinks, cooled byforced air (blown by fans), which are included. The six fans (threeon the laser head and three on the RF power supply) draw 3 A ofcurrent when supplied with the required 48 VDC electrical power.Running the fans at higher voltages will reduce the operating life and

3 - 5


is strongly discouraged. It is important to provide the correct voltagepolarity to the fans in order for the airflow direction and volume tobe sufficient to adequately cool the laser and RF power supply.

Air Flow For the GEM series of air cooled lasers, it is critical to have open airflow for both the laser head and the RF power supply. Therefore, werequire that there is clear access to free air within 100 mm of thecooling fans and fins for both the laser head and RF power supply.

Signal Interface It is also possible to use the signal interface in the laser interlocksystem to shut off the laser when the fans fail to operate. With thisapproach, the laser is commanded through the signal interface toshut down if the airflow interlock system detects excessive heat. Itis recommended that both Modulation and Power Supply Enable becommanded to the off state when the airflow interlock systemdetects an over temperature fault. These signals are listed inTable 4-1 and further discussed in subsections of Section Four:Laser Operation.

Over Temperature Interlock Switch

To prevent operating the laser accidentally without enough airflow,it is recommended that the OEM install a DC interlock so that thelaser assembly does not operate, unless the air temperature standardshave been met (Refer to Table 1-1). As a backup to such an inter-lock, the RF power supply incorporates a thermal shutdown feature,as discussed in Laser Operation. Therefore, the RF power supply isprotected even if the flow of air is interrupted, but no such backupprotection is provided for the laser head.

DC Power Relay The recommended DC power relay used to cut off DC power to thelaser in the event of cooling system failure can also be used as partof the laser safety interlock system. Similarly, if the signal interfaceis used to shut down the laser when there is a cooling system fault,it may be desirable to use the signal interface to shut down the laserin the event that there is a breach of a safety interlock. The design ofthe interlock controls must be in compliance with applicable safetystandards, including those described in the section entitled LaserSafety.

3 - 6


Electrical Power Connection

The GEM-100 laser requires 48 to 50 VDC input DC power. Thispower is carried from the power source to the RF power supplythrough the terminal block on the Model D-1000 RF power supply.The maximum current required is 49 A.

The negative (return) side of the DC input connection to theGEM-100 RF power supply is connected internally to the chassis.The user must assure that the system into which the GEM-100 isbuilt protects against the possibility that the GEM-100 laser head orRF power supply chassis could be at a hazardous voltage and thatpersonnel could be exposed to these voltages.

Figure 3-3. Electrical Connections to D-1000 RF Power Supply

3 - 7


To avoid potentially fatal electrical shock hazards from elec-trical equipment, be sure to follow all applicable electrical codessuch as (in the U.S.) the National Electrical Code.

It is strongly recommended that the user review the precautionsdescribed in Section Two: Laser Safety regarding electrical safetybefore using the GEM-100 laser. It is the users responsibility toprovide circuit breakers and/or fusing of the AC power source, inaccordance with all applicable laws and regulations.

DC Power Supply Requirements

The following are the requirements for the customer supplied DCpower supplies.

Regulation: <+/- 2%

Regulation Sensing: Remote at load

Ripple and Noise: <1% p-p (20MHz BW limit)

Overload and Short Circuit Protect Automatic Recovery

Control Signal Connection

Electrical control of the GEM-100 laser is through the 15-pin D-typeconnector built into the RF power supply, as shown in Figure 3-3.The signals carried on each of the pins are indicated in Table 4-1.Details of controlling the laser through the signal interface arediscussed in Section Four: Laser Operation.

RF Power Supply Connection

The connector attached to the RF power supply which carries thecontrol signals should be securely attached using the attachmentpoints provided on the RF power supply.

Coaxial Cable A special coaxial cable is used to connect the RF power supply to thelaser head. It is critical that only a qualified cable with suitable char-acteristics be used to connect the RF power supply to the laser head.The length, impedance, and power handling capability of the RFcable are critical to the proper functioning of the GEM-100 lasersystem.

3 - 8


To avoid possible damage to the RF power supply, always use thecorrect coaxial cable to connect the RF power supply to the laserhead, and make sure the cable connections are tight at bothends.

Any GEM-100 laser can be used with any of the Coherent/DEOS®supplied coaxial cables listed in the parts list. Never use any othercable to connect the RF power supply to the laser head, except thoselisted in the parts list. Unless the customer otherwise specifies, eachGEM-100 laser is delivered with the shortest cable among thoselisted in the parts list. That cable, P/N 1101-10-0025-01, has anominal length of 7.7 ft. (2.3 m). The RF cables are marked with thepart numbers shown in the table.

It is the responsibility of the user to ensure that the RF cable ismechanically secured so that mechanical forces due to flexing ofthe cable do not occur at the connectors.

Cable Connections and Torque

Avoid overstressing the RF cable. The RF cable should not be usedto support other cables, water lines, or other conduits or ducts. TheRF cable should be supported at least once in every meter of length.A separate steel cable can be used to provide intermediate supportpoints. Use cushioned supports to avoid crushing the RF cable.Avoid bundling the RF cable with other cables. The heat dissipatedby the operating RF cable will damage other cables bundled to it.Keep the inner bend radius greater than 2 inches (5 cm).

If both the laser head and RF power supply will be in a non-moving,non-vibrating environment, tightening the RF connectors by handshould be sufficient. However, if the laser head or the RF powersupply will be used in a dynamic or vibrating environment, theconnectors should be tightened with a torque wrench to(23 ± 3) in-lbs. [(2.6 ± 0.3) N-m], and retightened at least once permonth.

3 - 9


3 - 10

Laser Operation

SECTION FOUR: LASER OPERATION

Signal Interface Connectors

For all GEM-100 lasers, the signal interface between the GEM-100laser and the customers equipment is through a 15-pin D-type maleconnector which is built into the RF power supply. The pin assign-ments for the interface are indicated in Table 4-1. The signal inter-face and its use are discussed in detail in this section.

To avoid damage to the RF power supply, make sure your elec-tronic controller is compatible with the interface described inTable 4-1.

As noted in the Laser Safety section of this manual, the signal inter-face is designed to provide a high degree of reliability in the controlof laser output. The Laser Safety section should be reviewed forguidance on any use of the signal interface in safety interlocksubsystems, or in any other subsystem which affects personnelsafety.

Operating Modes

All GEM-100 lasers can be operated in CW Mode or Gated CWMode. Each mode is described in the following sections, details ofhow to operate the laser in each mode is also discussed.

It will be assumed in the discussion below that the laser has beeninitially started so the laser is now ready for operation.

Typical Waveform Figure 4-1 illustrates a typical periodic pulsed laser waveform. TheRF input to the laser will generally follow the Modulation signal(Table 4-1). The laser output will generally follow the RF input, butwill be distorted. The pulse repetition frequency PRF = 1/T, where Tis the period of the waveform. The duty cycle DC = (τ /T)x100where τ is the pulsewidth.

CW Mode To command any GEM-100 laser to operate in CW Mode, Modula-tion must be set continuously to Logic Level 1 (high).

4 - 1


Table 4-1. Signal Interface Description and Connector Pinout

PIN NO. FUNCTION DESCRIPTION

1 RS-423 MODULATIONInput signal (unbalanced)

The RS-423 specification requires a driver capable of delivering asignal between 4 V and 6 V into a test load of 450 Ω.

2(+)and3()

MODULATIONDifferential input signal(RS-422)

The RS-422 balanced specification requires a driver that is capable ofdeveloping a differential signal between 2 V and 10 V into a load of100 Ω.

4 ANALOG FORWARDVoltage output signal

Analog representation of the RF power supplys forward RF outputvoltage. 0 V to 5 V, 5 V = full scale. Signal will drive ≥10 kΩ load. Avoltage level lower than 2.5 V indicates a bad RF power supply. Seerepresentative signal curves for the particular GEM-100 RF powersupply.

5 ANALOG REFLECTEDVoltage output signal

Analog representation of the RF power supplys reflected RF outputvoltage. 0 V to 5 V, 5 V = full scale. Signal will drive ≥10 kΩ load. Avoltage level greater than 1.0 V may indicate either a bad laser head,a bad RF cable, or both. Call Coherent/ DEOS for advice if this condi-tion exists.

6 VSWR FaultOpen collector output

Will sink 25 mA of current when an VSWR fault occurs. This indi-cates an excessive mismatch between the laser head and the RF powersupply.

7 Not currently used.

8 VDCVoltage output signal

+15 VDC ± 0.5 VDC, 0.25 amp max output available from RF powersupply to user equipment.

9 GNDGround

Customer ground. Return line for all signals. Is also chassis ground.

10 Power Supply EnableTTL input signal

Enables internal DC power supply. TTL high will enable this pin.

11 MODULATION SELECTInput signal

Selects between unbalanced TTL modulation or Differential modula-tion signal. No connection selects unbalanced input (Pins 1 and 9).Ground this pin to selected balance inputs (Pins 2 and 3).

12 OVER TEMPERATUREOpen collector output

Will sink 25 mA of current when an OVER TEMPERATURE faultoccurs. This indicates that the RF power supply has gone over temper-ature.



15 OEM is required to ground this pin.

4 - 2

Laser Operation

Gated CW Mode The GEM-100 laser is capable of producing a wide range of pulserepetition frequencies (PRFs), pulsewidths, and duty cycles in GatedCW Mode. Modulation pulsewidths of less than 1 µs and/or PRFsgreater than 25 kHz are not advisable. Except for these restrictionson pulsewidths and PRFs, the RF power supply will support anyduty cycle from zero to 100% in Gated CW Mode.

Variable Output Power Capability; Pulsewidth Variation

All GEM-100 lasers provide the capability to continuously vary theaverage laser output power from near zero to at least the CW outputpower specified in Table 1-1. The user can implement this capabilityby adjusting the pulsewidth of the input command ModulationSelect.

Optical Pulse Shape When the pulsewidth of the input digital signal Modulation is varied,the pulsewidth of the RF input to the lasers electric discharge is alsovaried. Because of the complex dynamics of the electric dischargeand the laser resonator, the optical output from the laser will be adistorted version of the RF input waveform.

Adjustment of the RF pulsewidth to vary the laser output power isdone in Gated CW Mode. The recommended lower limit on pulse-width in Gated CW Mode is 1 µs.

Figure 4-1. RF Input Waveform and Laser Output Waveform

4 - 3


Complex Modulation Waveforms

There are a variety of potentially useful Modulation waveforms inaddition to simple periodic waveforms with a single pulse per periodof the waveform.

Varying the Pulsewidth

For example, some users may desire pulsed output, with fixed pulse-width but variable pulse energy. It may be possible to approximatethe ideal desired optical output by pulsing the laser at a relativelyhigh PRF (e.g., 25 kHz), then envelope modulating at a lower PRF(e.g., 1 kHz). Variation of the pulsewidth of the 25 kHz modulationwould then provide the ability to continuously vary the pulse energyof the 1 kHz pulses.

Protection from Unacceptable Inputs

The GEM-100 laser will easily accommodate complex Modulationwaveforms. The RF power supply will protect itself and the laserhead from damage due to inappropriate inputs, even for suchcomplex input waveforms.

Turning On the Laser

To turn on an GEM-100 laser and perform an output power check,do the following:

1. Make sure that the laser output aperture is clear and free ofpacking material.

2. Place a laser power meter head in a position to intercept theoutput beam, and turn on the power meter.

3. Verify that the laser head and the RF power supply do not havecondensation on their outer surfaces.

4. Verify that all required laser safety interlocks are positionedfor laser operation, if the GEM-100 laser is built into a systemwith safety interlocks.

5. Verify that other safety features, such as equipment covers,shutters, and warning lights are functional and operating prop-erly.

6. Verify that there is a solid electrical connection between thenegative DC input terminal on the RF power supply and earthground, as was discussed in the section titled Grounding.

7. Insure that all safety procedures, such as use of laser safetygoggles, are observed.

8. Turn on AC power to the DC power supply.

9. Turn on DC power to the RF power supply.

4 - 4

Laser Operation

10. Set the user-supplied control equipment to activate the laser inCW Mode, in accordance with the instructions below.

11. After a few seconds of laser operation, read and verify thepower level. The laser output should meet or exceed the laseroutput power specification given in Table 1-1.

12. Set the user-supplied control equipment to deactivate the laser.

13. Turn off DC power.

14. Turn off AC power.

Electronic Control

Your GEM-100 laser is controlled through the electronic interfacedescribed by Table 4-1. In this section, additional information isprovided about the use of this control interface. This discussionsupplements the discussion in the section entitled Signals Interfaceand Operating Modes and its subsections.

Use of the control interface in any strategy for assuring personnelsafety must comply with the design guidelines discussed in the LaserSafety section of this manual.

Electronic Signals Required to Turn On the Laser

The laser can be electronically commanded to turn on at any timethat DC power is applied to the RF power supply and the RF powersupply is properly connected to the laser head. It is recommendedthat all the control signals be set to their off condition until DCpower is applied to the RF power supply.

Modulation Select The signal named Modulation Select (Pin 11) should be set to thedesired value by grounding (earthing) the conductor connected toPin 11, or leaving it open. As indicated in Table 4-1 if Pin 11 is open,then Pin 1 (an unbalanced TTL input) will control the RF output andlaser output; if Pin 11 is grounded, then Pins 2 and 3 (an RS-422differential input) will control the RF output and laser output.

Start-up Sequence Mode Control (Pin 15) must be grounded by the OEM.

The recommended sequence to turn on the laser in CW Mode, afterDC power is applied, is as follows:

Set Power Supply Enable (Pin 10) to TTL high (logic 1). Thisenables the RF power supply by enabling DC power to aninternal control board.

Set Modulation to logic 1 (Pin 1, or Pins 2 and 3). This acti-vates the RF output of the RF power supply.

4 - 5


Response Times of Laser to Modulation, and Power Supply Enable

The response time of the RF power supply to Power Supply Enable(Pin 10), and to Modulation (Pin 1, or Pins 2 and 3) are quitedifferent. The response to Modulation is on a microsecond timescale, whereas the response to Power Supply Enable is on a timescale of milliseconds. This difference is not significant if the objec-tive is to use the power supply only in CW Mode. However, if it isdesired to use the power supply in Gated CW Mode, it is importantto take into account the response time of the power supply to PowerSupply Enable, and to Modulation. In general, it is best to turn theDC power supply on with Power Supply Enable and leave it onwhile modulating Modulation as required.

Signals Used for Fault Detection

Several of the signals listed in Table 4-1 may, at the customersoption, be used for diagnosing faults in the laser system. Theapproach that gives the easiest access to these signals is to provideindicators [such as light emitting diodes (LEDs)] on the customerssystem control console for three of these signals, as follows. Oneway to use these uncommitted collector signals is to sink the currentfor one LED on the operators control panel with each of thefollowing three signal leads:

Figure 4-2. Fault Detection Circuit

4 - 6

Laser Operation

VSWR Fault Indicator (Pin 6): This signal should be openunless the RF power supply has detected excessive RF powerreflected from the laser head, indicating a fault in the laserhead. A reasonable fault indication would be to turn on an indi-cator light labeled VSWR Fault whenever this signal isactive (i.e., available to sink current).

Over-Temperature Shutdown (Pin 12): This signal should beopen unless the RF power supply has shut down due to exces-sively high temperature. A reasonable fault indication wouldbe to turn on an indicator light labeled RF Power supplyThermal Shutdown whenever this signal is active (i.e., avail-able to sink current).

Two other output signals, named Forward Power Output Indicator(Pin 4) and Reflected Power Output Indicator (Pin 5) are availablefor diagnosing faults in the laser system.

See Section Five: Maintenance and Troubleshooting for guidance onhow to interpret and use indications by the above signals of faults inthe laser.

Do not ignore indications of faults in the laser system, eventhough the laser seems to be working normally otherwise.Continued operation in the presence of a fault may result indamage to the laser head or the RF power supply.

VSWR Faults During Initial Turn-on

The electric discharge in the laser head is more difficult to start afterextended non-operational periods. As a result, the laser may notimmediately start when it is first commanded to do so after morethan a few hours of being turned off (not lasing). This may occasion-ally result is the signal VSWR Fault Indicator becoming active(high), indicating an VSWR fault (i.e., high standing wave ratio inthe RF power cable due to failure of the electric discharge to light).Such transient indications of an VSWR fault when the laser is firstturned on each day do not indicate any fault in the RF power supplyor laser head. Therefore, we recommend that the VSWR fault is logi-cally qualified to be true for a time period of 1.0 seconds after lasermodulation and power supply enable have been active.

If the VSWR Fault Indicator signal indicates VSWR faults for morethan a second or so during the first operation of the laser on anygiven day, this may indicate a genuine fault in the laser system. Inthis case, the operator should proceed to the section of this manualentitled Section Five: Maintenance and Troubleshooting.

4 - 7


4 - 8

Maintenance and Troubleshooting

SECTION FIVE: MAINTENANCE AND TROUBLESHOOTING

Maintenance The GEM-100 laser heads and RF power supplies require no routinemaintenance.

Users should never open the covers on either the laser head orthe RF power supply. Opening these covers presents a safetyhazard, and is not useful since there are no user serviceableparts inside.

The protective covers of the laser RF power supply and the laserhead should never be removed by the user. There are no user service-able components inside. Opening the cover exposes the operator topotentially fatal electric shock hazards.

Cleanliness of Output Optical Element

The laser head should never be activated if the output opticalelement is contaminated by water, dust, dirt, or any other contami-nant. Operation of the laser head with any contaminant on thesurface of that optical element may result in damage to the coating.If any such contamination is present, the laser must be returned toCoherent/DEOS® so the problem can be corrected. The customerssystem design should also be reviewed to prevent a recurrence of thecontamination problem.

Troubleshooting Coherent/DEOS® recommends that the following checks beperformed before calling for service.

Connectors and Cables

Inspect all four RF connectors for evidence of overheating dueto improper installation of the RF cable.

If either of the two RF connectors on the RF cable is burned,the RF cable (with connectors) must be replaced as a unit.

Verify that the RF cable is installed as described in the sectionentitled RF Power Supply Connection.

5 - 1


If the RF connector which is part of the RF power supply, orthe RF connector which is part of the laser head, is discoloredor shows other signs of heat damage, return the RF powersupply or the laser head (as appropriate) to Coherent/DEOS®for replacement of the damaged connector.

DC Power and Voltage

Verify that DC power is available to the RF power supply.

Verify that the voltage on Pin 8 of the signal interfaceconnector is (+15 ± 0.5) VDC, as shown in Table 4-1. (Thelocation of the signal interface connector is shown, forexample, in Figure 3-2.)

If the voltage is not within the specified range, the RF powersupply is faulty and must be returned to Coherent/DEOS®.

Control Inputs Verify that the control inputs at the interface connector are setto appropriate values in accordance with Table 4-1.

The fault detection signals from the RF power supply arediscussed in the section entitled Signals Used for Fault Detec-tion.

Note the status of these signals when the laser is commandedto CW Mode (as described in the section entitled CW Mode).

VSWR Fault Indicator

If the fault detection signal named VSWR Fault Indicator(Pin 6 in Table 4-1) is active, try changing RF cables orswitching laser heads (if spare RF cables and/or laser heads areavailable) to see if the fault goes away with such substitutions.

If the VSWR fault indication goes away when the RF cable orthe laser head is replaced, the fault is probably in the itemwhich was replaced.

Over Temperature Shutdown

If the fault detection signal named Over-Temperature Shut-down (Pin 12 in Table 4-1) is active, troubleshoot the coolingsystem to determine why the RF power supply appears to beoverheating.

CW Mode If the laser output is non-zero, measure the laser output powerin CW Mode and compare it to the output power specified foryour laser model in Table 1-1.

5 - 2

Maintenance and Troubleshooting

The signal inputs required to place the laser in CW Mode arediscussed in the section entitled CW Mode.

Visualizing If the laser output is non-zero and you have access to any wayof visualizing the spatial structure of the output beam, performsuch a visualization and record the results.

Voltages With the laser commanded to CW Mode (as described in thesection entitled Electronic Signals Required to Turn On theLaser), measure the voltages on Pins 4 and 5 of the signalinterface. (This interface is described in Table 4-1).

The voltage on Pin 4 should be (4.5 ± 0.4) VDC.

The voltage on Pin 5 should be ≤0.7 ± 0.25 VDC.

If these voltages are not as stated, the RF power supply is prob-ably faulty and must be returned to Coherent/DEOS® forservice.

Output Beam If there is evidence that the spatial quality (Transverse Modequality) of the output beam is degraded, examine the outputoptical element of the laser head, looking for evidence ofdamage to the optical coating. (Of course, this examinationmust be performed with AC power to the laser system discon-nected.)

If such coating damage is present, the laser must be returned toCoherent/DEOS® so the problem can be corrected.

The customers system design should also be reviewed todetermine if contamination of the optical element could havecontributed to the coating damage.

If, after performing the above checks, you still believe there is aproblem with the laser, proceed to the section of this manual entitledWarranty.

5 - 3


Figure 5-1. GEM-100 Voltage Chart

020406080

100120140160180200

0 20 40 60 80 100

Operating Duty Cycle, % (At 24 kHz)

Opt

ical

Out

put P

ower

, Wat

ts

0.000.501.001.502.002.503.003.504.004.505.00

Out

put V

olta

ge, V

olts

Poptical Vfwd Vref

5 - 4

Parts List

PARTS LIST

The following parts can be ordered by contacting Coherent/DEOSCustomer Service at 1-800-367-7890 (within USA) or1-408-764-4557 (outside USA) or your local Coherent/DEOS repre-sentative.

Preferred Liquid Configuration

Preferred Air Configuration

Table A-1. GEM-100 (100 Watts) Laser System - Typical Configurations

SYSTEM LASER HEAD RF SUPPLY CABLE DESCRIPTION

GEM-100L 1400-00-0003 7203-00-0001 1101-10-0025-1 Liquid cooled/220 VAC

GEM-100A 1400-00-0011 7223-00-0001 1101-10-0025-1 Air cooled (fins and fans)

Table A-2. GEM-100 (100 Watts) Laser Component Part Numbers

PART NUMBER DESCRIPTION NOTES

LASER HEADS

1400-00-0003 GEM-100L Laser Head (liquid) Water cooled

1400-00-0011 GEM-100A Laser Head (air) Air cooled

1400-00-0013 GEM-100A Laser Head (fins wo/fans) Special (customer supplied fans)

RF POWER SUPPLY

7203-00-0001 D-1000 RF Power Supply (liquid) Water cooled/220 VAC

7223-00-0002 D-1000 RF Power Supply (air) Air cooled (fins and fans)/48 VDC

7223-00-0001 D-1000 RF Power Supply (fins wo/fans) Special (customer supplied fans)/48 VDC

CABLES

1101-10-0025-01 Cable, RF, 2 Half Waves Length is 7.7 feet (2.3 meters)



1401-10-0042 Cable, RF, 1 Half Waves Length is 3.7 feet (1.1 meters)



A - 1



1101-10-0091 Flexible RF Cable, 3 Half Waves Length is 11.8 feet (3.6 meters)





Table A-2. GEM-100 (100 Watts) Laser Component Part Numbers (Continued)

PART NUMBER DESCRIPTION NOTES

A - 2

Warranty

WARRANTY

GEM Series Laser Warranty

Coherent, Inc. warrants to the original purchaser that the GEM-100laser system conforms to the specifications published by Coherentand is free from defects in materials and workmanship.

For specific warranty terms and conditions for your GEM-100 lasersystem, refer to your sales contract.

GEM-100 laser systems are warranted for parts and labor for aperiod of twelve (12) months. Warranty begins from the date of ship-ment.

GEM-100 laser systems do not include installation in the purchaseprice.

Conditions of Warranty

For warranty service requiring the return of any product to Coherent,the product must be returned to a service facility designated byCoherent. The Buyer is responsible for all shipping charges, taxesand duties.

Parts replaced under warranty shall become the property of Coherentand must be returned to Coherent, Inc., Santa Clara, or to a facilitydesignated by Coherent. All laser systems must be carefully packedin a suitable shipping container(s). Coherent does not assumeresponsibility for components broken in shipment due to improperpackaging or handling. The Buyer will be obligated to issue apurchase order for the value of the replaced parts and Coherent willissue credit when the parts are received.

Responsibilities of the Buyer

Damage to the GEM-100 laser caused by failure of Buyer's utilitiesor the Buyer's failure to maintain an appropriate operating environ-ment, is solely the responsibility of the Buyer and is specificallyexcluded from any warranty.

The Buyer is responsible for prompt notification to Coherent of anyclaims made under warranty. In no event will Coherent be respon-sible for warranty claims later than seven (7) days after the expira-tion of the warranty.

B - 1


Limitations of Warranty

The foregoing warranty shall not apply to defects resulting from:

1. Components or accessories with separate warranties manufac-tured by companies other than Coherent.

2. Improper or inadequate maintenance by Buyer.

3. Buyer-supplied interfacing.

4. Operation outside the environmental specifications of theproduct.

5. Improper site preparation and maintenance.

6. Unauthorized modification or misuse.

Coherent assumes no responsibility for customer-supplied material.

The obligations of Coherent are limited to repairing or replacing,without charge, equipment that proves to be defective during thewarranty period. Replacement systems may contain reconditionedparts. Repaired or replaced parts are warranted for the duration ofthe original warranty period only. This warranty does not coverdamage due to misuse, negligence or accidents, or damage due toinstallations, repairs or adjustments not specifically authorized inwriting by Coherent.

B - 2

Glossary

GLOSSARY

% Percent°C Degrees centigrade or Celsius°F Degrees Fahrenheitµm Micrometers = 10-6 metersµrad Microradians = 10-6 radiansµs Microseconds = 10-6 seconds1/e2 Beam diameter parameter = 0.13534

A AmperesAC Alternating currentANSI American National Standards Institute

BNC Type of connector

CaCO3 Calcium carbonateCDRH Center for Devices and Radiological Health (part of the Food and

Drug Administration of the Public Health Service, U.S. Departmentof Health and Human Services)

CFR Code of Federal Regulationscm Centimeters = 10-2 metersCO2 Carbon dioxideCW Continuous wave

DC Direct currentDCPS DC power supplyDEOS DeMaria ElectroOptics SystemsDVM Digital voltmeter

EMC Electromagnetic compatibility

FDA Food and Drug Administration (an agency of the U.S. Departmentof Health and Human Services)

FPT Female pipe threadft. Foot (Feet) (length)

gpm Gallons per minute

hex HexagonHz Hertz or cycles per second (frequency)

I.D. Inner diameterIEC International Electrotechnical Commissionin. Inch(s) (length)IR Infrared

kg Kilograms = 103 gramskHz Kilohertz = 103 hertzkPa Kilopascals = 103 pascalskV Kilovolts = 103 volts

Glossary - 1


kW Kilowatts = 103 wattskΩ Kilohm(s)

lbs. Pound(s)LED Light emitting diode

m Meter(s) (length)mA Milliamperes = 10-3 Amperesmg Milligrams = 10-3 gramsMHz Megahertz = 106 HzmJ Millijoules = 10-3 Joulesmm Millimeters = 10-3 metersMNPT Male National Pipe Thread mrad Milliradians = 10-3 radians (angle)ms Milliseconds = 10-3 secondsmW Milliwatts = 10-3 Watts (power)

N2 Nitrogennm Nanometers = 10-9 meters (wavelength)N-m Newton-meter(s)NPT National Pipe Thread American national standard taper pipe thread

(American National Standards Institute, B2-1-1968)

Ø PhaseO.D. Outer diameterOEM Original Equipment ManufacturerOSHA Occupational Safety and Health Administration, part of the U.S.

Department of Labor

P/N Part number ppm Parts per million (by weight)PRF Pulse repetition frequencypsi Pounds per square inchpsig Pounds per square inch, gauge (pressure relative to ambient

atmospheric pressure in psi)

RF Radio frequencyRMA Return material authorizationRMS Root mean square (effective value of a sinusoidal wave)

SS Stainless steelSTD Standard

TEM Transverse electromagnetic (cross-sectional laser beam mode)TTL Transistor-to-transistor logic (Designed to +5 V nominal maximum

voltage)

V VoltsVAC Volts alternating currentVDC Volts direct currentvol% Volume percentVSWR Voltage, standing wave ratio

W Watts

Glossary - 2

Packing Procedure

PACKING PROCEDURE

The following is the factory recommended packing procedure forthe GEM laser system. This procedure should be followed if thelaser system is to be shipped to another location after initial installa-tion, or returned to the factory for service. It is recommended thatyou save the shipping box and packing materials, since these will beuseful should you need to ship the laser back to Coherent/DEOS.

Never ship or store any GEM laser head or RF power supplycontaining coolant if it is possible it will be exposed to tempera-tures below the freezing point of the coolant during such ship-ment or storage. Plug or cap coolant inlet and outlet to preventcoolant leaks during shipment or storage.

For Liquid Cooled Lasers/ RF Power Supplies

1. Uncouple the laser head and RF power supply from the chiller.

2. Drain the cooling lines into the proper drain/receptacle.

3. Blow out the cooling lines on both laser head and RF powersupply using compressed air (<75 psi).

4. Seal the cooling lines with the caps/plugs originally suppliedwith the laser system.

Be sure to drain all cooling liquid from the laser head and RFpower supply prior to packing for shipment. This can be accom-plished by lightly blowing compressed air into the cooling lines.

For All Laser Heads (After Draining and Clearing Cooling Lines for Liquid Cooled Laser Systems)

1. Seal the output coupler/window with tape.

2. Wrap the laser head in protective plastic bag/sheet. Seal withtape. (In the event that the original shipping container is notavailable, wrap the laser head in bubble-wrap protectivepacking so that the laser head has a least 4 inches of protec-tive packing around the entire laser).

3. Package the laser head in the original inner shipping containerand seal with packaging tape.

C - 1


For All RF Power Supplies (After Draining and Clearing Cooling Lines for Liquid Cooled Laser Systems)

1. Wrap the RF power supply in protective plastic bag/sheet. Sealwith tape. (In the event that the original shipping container isnot available, wrap the RF power supply in bubble-wrapprotective packing so that the RF power supply has a least4 inches of protective packing around the entire laser).

2. Package the RF power supply in the original inner shippingcontainer and seal with packaging tape.

Shipping Instructions

1. Place the return shipping label(s) (located on the page after theRMA Form) on the shipping the container(s) WITH THERMA NUMBER CLEARLY VISIBLE and ship toCoherent/DEOS. The shipper should be notified that thecontents are fragile and sensitive to shock and moisture

2. Enclose a copy of the completed RMA Form in the return ship-ping container. Retain a copy for your records.

3. Package carefully, both the laser head and RF power supply inthe original Coherent/DEOS outer shipping container(s).

RMA Form Instructions

Call your local Coherent Service Representative to obtain an RMAnumber prior to filling out this form. After receiving an RMAnumber, this form should be filled out and accompany your returnshipment.

1. Date and RMA NumberEnter todays date and RMA number. Upper right hand corner.

2. Requestor InformationProvide all of requestors address and ship to address informa-tion. Provide customer reference number if applicable.

3. System InformationProvide system product number, system serial number.Note: Enter None for Service Inventory Returns.

4. Return Part(s) InformationProvide the part number, description, serial number (if appli-cable) and quantity of returned part(s).

5. Failure Information/CommentsProvide failure details or explain why the part(s) is beingreturned.

C - 2

Please fill out this form and include with the return shipment.In Order To Process, Form Must Be Complete

*coherenT/deos1280 Blue Hills AvenueBloomfield, CT 06002(800) 367-7890www.coherentinc.com

RMA FORM

Date

RMA Number

Requestor Information Cust Ref #_____________ Ship to InformationOrganization Organization

Contact Contact

Address Address

City City

State / Zip State / Zip

Telephone Telephone

Fax Number Fax Number

System InformationSystem Product Number System Serial Number

Return Part(s) Information Enter the following information, include applicable serial numbers.

Part Number Description Serial Number Quantity

Failure Information/Comments Explain why this part is being returned and/or provide failure details.

Ship to:

coherent/deos1280 Blue Hills AvenueBloomfield, CT 06002Attn.: Customer Service

RMA # ________________________

Ship to:

coherent/deos1280 Blue Hills AvenueBloomfield, CT 06002Attn.: Customer Service

RMA # ________________________

Index

INDEX

AAir cooling 3-5

DC power relay 3-6Interlock switch 3-6Signal interface 3-6vs. liquid cooling 1-3

Air flow 3-6Ambient air

Cleanliness 3-5

CCable

Coaxial 3-9Connections 3-9Lengths 1-2

Cables 5-1Certifications

Compliance 2-8Cleanliness

Ambient air 3-5Output optical element 5-1

Coaxial cable 3-9Compatibility 1-5Complex modulation waveforms 4-4Compliance

Certification 2-8Standards relevant to CE mark 2-4

ConnectionControl signal 3-8Electrical power 3-7Power supply 3-8

Connectors 5-1Control signal

Connection 3-8Cooling

Requirements 1-3CW mode 4-1

DDC input power 1-3

EElectrical

Power connection 3-7Safety 2-3

Electronic control 4-5Electronic signals required to turn on the laser 4-5

FFault detection

Signals used 4-6

GGated CW mode 4-3

HHardware configuration 1-2Hardware overview 1-3

IInspection 3-1Interchangeability 1-5Interference

Potential of the system 2-4Interlocks

Safety 2-4

LLaser head 1-4

Mounting considerations 3-5Laser installation

Safety issues 3-2

MMaintenance 5-1Mechanical mounting 3-2Mounting considerations

Laser heads 3-5Power supply 3-5

OOperating modes 4-1

CW mode 4-1Gated CW mode 4-3Typical waveform 4-1

Optical pulse shape 4-3Optical safety 2-1

PPacking procedure C-1Power supply 1-4

Connection 3-8Mounting considerations 3-5

Protection from unacceptable inputs 4-4Pulsewidth variation 4-3

RRadiated emission compliance 2-4Requirements

Cooling 1-3Input 1-2

SSafety

Index - 1


Electrical 2-3Interlocks 2-4Labels, location of 2-5Laser head 2-3Optical 2-1Requirements 2-3

Signal interface connectors 4-1Signals used for fault detection 4-6Specifications 1-2System

Interference potential of 2-4

TTorque 3-9Troubleshooting 5-1

Control inputs 5-2Coolant 5-1CW mode 5-2DC power and voltage 5-2Output beam 5-3Over temperature shutdown 5-2

Visualizing 5-3Voltages 5-3VSWR fault indicator 5-2

Turning on the laser 4-4Typical waveform 4-1

UUnpacking 3-1

VVariable output power capability 4-3Varying the pulsewidth 4-4Verifying delivery 3-1VSWR faults 4-7

WWarranty B-1

Conditions of B-1Limitations of B-2Responsibilities of the buyer B-1

Index - 2

Operator Manual Series GEM OEM Industrial Lasers GEM

Documents

Transcript of Operator Manual Series GEM OEM Industrial Lasers GEM