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OFFICE AUTOMATION – I

MODERN OFFICE EQUIPMENT

9. USE OF PRESENTATION EQUIPMENT: OVER HEAD PROJECTOR AND LCD PROJECTOR

This lesson introduces you to the world of presentation machines .These machines are very common in any modern office and are used during meetings to present data, diagrams or figures on a large screen. These machines provide great visibility of content and data that is being presented to everybody attending the meeting. The 2 machines are”

• The OHP or Over Head projector

• The LCD or Liquid Crystal Display projector . These have become invaluable tools in any office now.

9.0 Objectives After going through this lesson, you will be able to identify the following:

• Understand the history and development of projection equipments.

• Identify the basic components of these equipments

• Understand the principle of operation

• Know the key features of various projection equipments

• Understand their application and utility in modern office

• Evaluate the advantages and disadvantages in day to day office situations

9.1 Introduction Now that we have understood different communication equipments and copying machines in previous chapters, we shall dedicate this lesson to learn about various projection equipments. Different communication equipments are used in modern office scenario based on the conditions and requirements. Projection equipments are critical for most meetings today as they enable a speaker to project his notes, figures, diagrams on a large screen, so that they are easily visible to others attending the meeting

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9.2 Over Head Projector An overhead projector is a display system that is used to display images to an audience. They typically consist of a large box containing a very bright lamp and a fan to cool it, on top of which is a large lens that gathers all the light coming from the lamp and adjusts it in a parallel manner. Above the box, typically on a long arm, is a mirror that redirects the light forward instead of up. Sheets of transparent material called Transparencies, on which the data that is required to be shown as a projection is present, are placed on top of the lens for display. The light from the lamp travels though the transparency and into the mirror where it is shown forward onto a screen. The mirror allows both the presenter and the audience to see the image at the same time, the presenter looking down as if writing, the audience looking forward at the screen. Overhead projectors were once a common fixture in most classrooms and business conference rooms, but today are being replaced by larger computer monitors and dedicated computer projection systems. Critics feel that there are some downsides as they are much more prone to failure and have a much steeper learning curve than a standard overhead projector. Although with a computer projection system, there is no longer a need to create hard copy transparencies of the slide show presentation.

9.3 Types of Projectors There are two basic types of overhead projectors - transmissive and reflective. Transmissive projectors:

• Light source (bulb) is in the base of the machine; Light projected up through the glass stage of the projector, through a lens in the projector's head and then onto a projection screen

• Brighter, with sharper images

• Large size and heavy weight

• Great for computers using Liquid Crystal Display projection panels

Reflective projectors:

• Light source in head of projector; Light shines down onto a reflective stage, and then reflects back up through the lens and onto a screen

• Smaller size and lighter weight yield greater portability

• Great for transparency film use Before purchasing or using an overhead projector, it is a good idea to become familiar with the following components and options.

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9.4 Components of an Over Head Projector We shall now talk about various components that go into making an Over Head Projector work:

Lenses The lenses of an OHP come in three different variations:

• Singlet (most basic)

• Doublet

• Triplet (most advanced) The Projected images get sharper as lens quality increases. Along with that, the price of an overhead projector increases with upgrades in the lens quality. Projector's focal length, which determines how close to or far from the screen the projector will focus, is associated with type of lens used. Lamps The lamp is the most critical component of all overhead projectors. The lamps may vary in type, life, wattage and cost.

• Lamps normally offer a high/low switches or are built to double the life of the lamp, reducing lamp replacement costs

• "Lamp changer" feature allows the presenter to switch over to another lamp. This actually assures that a meeting will continue, even if a lamp fails.

Mirror hard top (lamp below)

Lens

Mirror

Plastic casing (Fan inside)

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Brightness Brightness of the light projected by the OHP is measured in lumens. For an average OHP it ranges from 1,700 to 11,000 lumens depending on the model. Factors dictating desired brightness:

• Type of image to be displayed (black/white or color)

• How image (transparency film or LCD panel) is projected

• Brightness of the room At least 1200 lumens is recommended with use of an OHP with transparencies and 4000 lumens for use with an LCD panel on the OHP. panel. Cooling Fan This cools the light source and prevents excess heat build up.

Mirror • This is used to reflect the image of the transparency created by the strong

bulb below it. The mirror gathers the light coming through the lenses and changes its direction. This is directed towards the screen where it is to be projected.

• The mirror should be kept clean all the time otherwise the image being reflected would be dulled.Ensure that the mirror is cleaned only with a dry cloth and not with water or cleaning fluids.

Transparencies A transparency is a thin sheet of transparent flexible material, typically celluloid, onto which figures can be drawn or written. The figures can be made by either using:

• Special OHP pens ( coloured)

• Photocopying on to the transparency( only Black/white)

• Inkjet printing on the transparency ( colour as well as Black/White) These are then placed on an overhead projector for display to an audience. This system is still found in schools, but is being largely replaced by LCD projector.

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9.5 Advantages of Overhead Projectors Following are the main advantages of using an Over Head Projector:

• Face to face contact with audience o Eye contact possible o Can pick up verbal and nonverbal cues to understanding

• Projector located in front of room and near speaker for easy access

• Can be used to focus audience's attention o It can be switched “On” to focus attention on visual material and o Switched “Off” to focus attention on to the speaker

• It is effective in a room of normal size ( seating about 15 people) and the audience can follow handouts or take notes as the room is not darkened for the presentation.

• Real time modifications are possible .You have the ability to modify transparencies during presentations by either o Highlighting important points with transparency pen or o Writing on a blank transparency directly

• Sequence of material can be modified during presentation o Accommodates audience questions or interest o You can abbreviate or extend sections of presentation without the

audience knowing it

• Unframed transparencies are easy to store and transport; they easily fit in a standard file folder

• Overlays can be used to simplify complex information into layers ie you can create more than one transparency and then keep them one by one on top of each other to show overlays in layers.

• Short lead time (minutes) for preparation of transparencies

• Low cost of transparency material

• Transparencies are reusable

9.6 Limitations of Overhead Projectors Finally, let us also consider some apparent disadvantages of using an OHP:

• Creating color transparencies is very costly and not an easy task

• Overhead projector is bulky and heavy to transport

• Photocopies of pages from books on to a transparency cannot be used effectively without modification since text will usually be too small for audience to read.

• Overhead projection is perceived as being "less professional" than slides in a formal setting. These days the OHP is being quickly replaced by the LCD projector due to the ability of the LCD projector to use inputs from a computer directly.

However, in organizations like schools, colleges etc , where cost of equipment is a key criteria , the OHP is still popular and is used very regularly.

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Self-Check Questions Answer True or False 1. Real time modifications are possible with an OHP? 2. An OHP is a very simple machine to operate ? 3. OHP machine does not require electricity ? 4. You can use any paper to project from an OHP ? Fill in the blanks 5. A transparency is a thin sheet of ____________ flexible material, typically

celluloid, onto which figures can be drawn or written. 6. The ____________ is used to reflect the image of the transparency created by

the strong bulb below it.

9.7 LCD Projector The LCD projector is fast replacing the OHP. Modern businesses use a lot of office automation in the form of electronic data through computers. It therefore becomes relevant to make multiple uses of the data available in various formats in electronic form. The OHP had a disadvantage that it could not use the output from a computer directly. Some attachments were developed but these were not reliable. The OHP was also not very bright and in well lit rooms the presentations would not be visible. LCD, or Liquid Crystal Display projector was developed to overcome these issues. It uses a powerful light passed through a transparent LCD chip containing video pixels. The video pixels are magnified through a lens and then projected onto a screen. LCD projectors offer solid contrast and brightness and are often easily portable. LCD projectors are subject to pixel burn-out, which can leave annoying black or white dots on the screen, and cannot run for more than 4-5 hours without risking overheating and pixel burn-out.

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9.8 Essential accessories you would find with an LCD projector

Along with the LCD projector, there are a few other accessories that are required to operate the projector. These are:

• Signal Cable – Carries display signals from a computer source to the projector.

• Power cable – The cable that connects into an electricity source.

• Remote control – is an accessory that makes it more convenient to use a Projector, during a presentation.

9.9 Understanding an LCD Projector An LCD projector is a compact rectangular casing, in construction. The front panel contains the lens, which projects the image on a screen upon magnification. The magnification is controlled by a Zoom lever, which is normally positioned along the circumference of the lens. The rear panel houses the terminal panel where all connectors are placed. The signal cable and the power cable are attached are attached on the terminal panel. The terminal panel can be placed on one of the side faces also in some cases, as shown in the line diagram below. The Control panel is normally placed on the top surface of the projector. As the name suggests, all operations / functions are controlled through this top panel only.

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A Remote control comes handy when you have to operate the projector while making a presentation. It becomes an absolute necessity, if your projector is mounted on ceiling and in cases where the controls are not physically accessible. The Control Panel

Projector – Front face Projector – Rear Panel face

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• Power Button (ON / STAND BY) – This button is used to turn the power ON or OFF, when the power is supplied and the to turn the power on and off when the power is supplied and the projector is in standby mode.

• Status Indicator - When this is lit red continually, it’s warning you that the Projection lamp has exceeded 2000 hours (up to 3000 hours in Eco mode) of service. After this light appears, it is advisable to replace the projection lamp as soon as possible. If this light blinks red rapidly, it indicates that the lamp cover or filter cover is not attached properly or the projector is overheated.

• Power Indicator ( ) - When this indicator is green, the projector is on; when the indicator is orange, it is in standby mode.

• Select ( ) / (+) (–) Buttons - These buttons are used to select the menu of the item you wish to adjust.

• : Use these buttons to select the menu of the item you wish to adjust.

• : Use these buttons to change the level of a selected menu item.

• When an image is magnified, these buttons can be used to move the image on screen.

• Cancel Button - Press this button to exit the menu. While you are in the adjustment or setting menu, pressing this button will return to the previous menu.

• Enter Button - Executes your menu selection and activates items selected from the menu

• Menu Button - Displays the menu.

• Source Button - Use this button to select a video source such as a PC, VCR or DVD player.

• These controls will vary from brand to brand.The most popular brands are ‘Sharp’, ‘Canon’ , ‘Toshiba’ , ‘Epson’ etc

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The Terminal Panel

• RGB Input Connector – is used to connect your PC or other RGB equipments. The supplied signal cable from this connector is connected to a PC.

• RGB Monitor Output Connector - This connector is used to loop your computer image to an external monitor from the RGB input source.

• Audio Input / Output Mini Jack - This is where you connect audio output from your computer. Alternatively, you may connect additional external speakers here to listen to audio coming from your Video or S-Video input.

• Audio Input / Output Connector (RCA) - This is where you connect audio output from a VCR, DVD player, or laser disc player. Alternatively, you may connect additional external speakers to listen to audio coming from your RGB source.

• Video Input (RCA) – This connector is to be used to connect a VCR, DVD player, laser disc player, or document camera to project video.

• S-Video Input Port (Mini DIN 4 Pin) – Used to connect the S-Video input from an external source like a VCR.

• PC Control Port (Mini DIN 8 Pin) - Use this port to connect your PC to control your projector. This enables you to use your PC and serial communication protocol to control the projector.

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Thus summarizing all connections together:

9.10 Important tips to keep in mind while using a projector

• For best results, use your projector in a darkened room.

• Place the projector on a flat, level surface in a dry area away from dust and moisture.

• Do not place your projector in direct sunlight, near heaters or heat radiating appliances.

• Exposure to direct sunlight, smoke or steam can harm internal components.

• Handle your projector carefully. Dropping or jarring can damage internal components.

• Do not place heavy objects on top of the projector.

Self-Check Questions

7. What does ‘LCD’ stand for ? Answer True or False

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8. The OHP can be used easily with a computer – True or False? 9. The LCD projector can be run for 2 days continuously – True or False ? 10. LCD projectors are cheaper than OHP – True or False?

9.11 Summing Up In this lesson you have learnt about 2 very important presentation equipment used very widely in many organisations today. These equipment are very simple to operate and do not require a high level of knowledge of computers .You have also learnt how to use these machines and their advantages as well as their limitations. It is recommended that you observe these machines in operation either at some school/ college or at some organisation.

9.12 Answers to Self-Check Questions

1. True 2. True 3. False 4. False 5. Transparent 6. Mirror 7. Liquid Crystal Display 8. False 9. False 10. False

9.13 Terminal Questions 1. What is an OHP projector ? Where is it primarily used now a days ? 2. How does one make a presentation using an OHP ? Please outline all the

steps. 3. What are the types of OHP’s? 4. Outline the key parts of an OHP. 5. What are the limitations of an OHP? 6. What care should be taken while running an LCD projector? ? 7. What are the major functions available on the control panel of a LCD

projector? 8. Why is a LCD projector better than an OHP? 9. Where can an OHP be used and not an LCD projector? 10. List out comparative advantages and dis-advantages of an LCD projector over

an OHP?

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9.14 Glossary Over Head Projector Transparencies: Sheets of plastic that are transparent and are used to project information on to the board after it is written on them using special pens. LCD Projectors: Resolution: Measures the amount of detail that can be seen in an image. Zoom: This is the magnification level of the image when projected on to the screen. Lumen : This is the intensity of light that is produced in the projector .