Micro Optical Table as the new platform for a Micro Optical Table as the new platform for a family of miniaturized optical systems: family of miniaturized optical systems:

4M Device case example 4M Device case example

Tomasz S. TkaczykTomasz S. Tkaczyk11, ,

EustaceEustace L. DereniakL. Dereniak11, Steve D. Gaalema, Steve D. Gaalema22, , William BahnWilliam Bahn22, Jeremy D. Rogers, Jeremy D. Rogers11, Todd C. Christenson, Todd C. Christenson33,,

Rebecca Richards-KortumRebecca Richards-Kortum44, Michael R. Descour, Michael R. Descour11

11Optical Sciences Center, University of Arizona, Tucson, AZ 85721Optical Sciences Center, University of Arizona, Tucson, AZ 8572122Black Forest Engineering, Colorado Springs, COBlack Forest Engineering, Colorado Springs, CO

33HT Micro, Albuquerque, NM 87109HT Micro, Albuquerque, NM 8710944Biomedical Engineering Program, University of Texas, Austin, TX 78712Biomedical Engineering Program, University of Texas, Austin, TX 78712

4M Device4M Device

• Miniaturized compound microscope for imaging molecular features of pre-cancer of oral cavity.

• 5.0mm(W)×13.0mm(L) ×2.5mm(H)• Battery powered and pen-sized.• Multi-modal capability:

– Reflectance imaging, – Fluorescent imaging– Optical sectioning

Folding Folding MirrorMirror

Hybrid Hybrid LensesLenses

CMOS CMOS image sensorimage sensor

BeamBeamSplitterSplitter

Condenser Condenser LensLens

LightLightSourceSource

Micro Optical Table (MOT)Micro Optical Table (MOT)Objective Objective LensLens

Object in Object in WaterWater

Sinusoidal Sinusoidal GratingGrating

Micro Optical TableMicro Optical Table

Micro Optical TableMicro Optical Table

Optics –TechnologyOptics –Technology

• Rotational symmetric grayscale photomask controls UV dose at given radial Rotational symmetric grayscale photomask controls UV dose at given radial distance.distance.

• Optical density is determined based on characterization curve that is Optical density is determined based on characterization curve that is experimental data.experimental data.

• It controls patterning of nearly arbitrary optical surfaces.It controls patterning of nearly arbitrary optical surfaces.

Grayscale photomask

Normalized OD vs Normalized Lens Profile

0

0.2

0.4

0.6

0.8

1

0 100 200 300 400 500 600 700 800

Radius (um)

No

rma

lize

d O

D,

Le

ns

Pro

file

Normalized OD

Lens Profile

Optics – DesignOptics – Design

• NA=0.4 to 0.7 (Object Space)NA=0.4 to 0.7 (Object Space)• Wavelength=0.60 to 0.83Wavelength=0.60 to 0.83μμmm• Full Field of View=220 to 250 Full Field of View=220 to 250 μμmm• Magnification=-4X to -7XMagnification=-4X to -7X• Working Distance=300 Working Distance=300 μμmm• Water ImmersionWater Immersion• One objective lens from Edmund optics and 3 lenslet One objective lens from Edmund optics and 3 lenslet

fabricated by photo-lithographic technique.fabricated by photo-lithographic technique.

3 equal lenslets made of sol-gel material

Water

Imaging Target

Objective Lens

Tilted System – Removing ReflectionsTilted System – Removing Reflections

Symmetric vs. Tilted SystemSymmetric vs. Tilted System

Symmetric SystemSymmetric SystemNo AR coatingsNo AR coatings

Tilted SystemTilted SystemNo AR CoatingsNo AR Coatings

System PerformanceSystem Performance

Strehl = 0.75Sag = 83.0 m

SagSag StrehlStrehl

76.076.0mm 0.800.80

80.080.0mm 0.970.97

84.084.0mm 0.820.82

Scanning MechanismScanning Mechanism

• Dimensions (screen size) – 1.3 mm Dimensions (screen size) – 1.3 mm x 1.3 mmx 1.3 mm

• Grating Frequency – 50, 60, 75, 90, Grating Frequency – 50, 60, 75, 90, 100 l/mm 100 l/mm

• Grating Profile - rectangularGrating Profile - rectangular• Scanning Freq. – 25 to 500 HzScanning Freq. – 25 to 500 Hz• Battery Powered – 1.5VBattery Powered – 1.5V• Oscillation Amplitude < Oscillation Amplitude < 100 100 mm

Signal Modulation Frequency at the Signal Modulation Frequency at the detectordetector

25 Hz to 10 kHz25 Hz to 10 kHz

Parameters SummaryParameters Summary

• OpticalOptical– Magnification = -4X to -7XMagnification = -4X to -7X– NA = 0.4 to 0.7NA = 0.4 to 0.7 = 0.60 to 0.83 = 0.60 to 0.83 mm– Field of View = 200 to 250 Field of View = 200 to 250 mm

• Structured Illumination TechniqueStructured Illumination Technique– Signal frequency (25-100Hz)Signal frequency (25-100Hz)– Number of Images for reconstruction 16 to 64Number of Images for reconstruction 16 to 64– Number of Images/cycle 3 to 5Number of Images/cycle 3 to 5

Fast CMOS detector arrayFast CMOS detector array

• 344x344 pixels344x344 pixels• 1.38x1.38 mm1.38x1.38 mm22 detection area detection area• 4 mm4 mm22 total CMOS area total CMOS area• 4x4 4x4 mm22 pixel size pixel size 50% filling factor (50% filling factor ( 3x3 3x3

mm22))• 12-bit resolution12-bit resolution• Frame Rate Frame Rate ≤≤ 500 frames/sec 500 frames/sec• RollingRolling integration integration• Operation wavelength Operation wavelength = 630 = 630

to 830 nm (830 nm is the to 830 nm (830 nm is the ultimate wavalength)ultimate wavalength)

Power specificationsPower specifications

Total chip power (worst case), mW 59.0VddA, v 3.6 54.7

Vdd, v 2.5 4.3

Supply currents, mAVddA 15.2Vdd 1.7

The final chip size is 1.52mm x 2.6mmThe final chip size is 1.52mm x 2.6mm

Column Buffer Array

Row Decoder & Pixel Reset/Enable Circuitry

Pad Names

Bonding Pads

Testing/Debugging Pads

Vdd

Pfs

Dls

Pmc

Pmod e

Vss

VssA

Vggo

Vref

Vout- D

Vout- D

Vout- C

Vout- C

Vout- B

Vout- B

Vout- A

Vout- A

VddA

Output Driver

Column Decoder

Single-ended to differential OPAMP

Single-ended to differential OPAMP

Ramp Generator

Background problem in reflectance imagingBackground problem in reflectance imaging

Images of phantoms containing SiHa cervical cancer cells labeled with anti-EGFR gold conjugates. The field of view is 54 × 54 m2. The approximate depth of the imaged optical section is 15-20 m below the phantom surface. Part (a) shows an inverted widefield reflectancemicroscope image. Part (b) shows a structured-illumination raw image. Part (c) shows a reconstructed optical-section image

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Future challengesFuture challenges

• CMOS testing and implementationCMOS testing and implementation• Integration of 4M Device Integration of 4M Device

• New optical designs and ImplementationsNew optical designs and Implementations

AcknowledgementAcknowledgement

I would like to thank my colleagues from all groups I would like to thank my colleagues from all groups participating in the project, for delivering materials participating in the project, for delivering materials

for the presentation. for the presentation.

This project is funded by NIH, NCI and NIBIBThis project is funded by NIH, NCI and NIBIB