3M Electronics Materials Solutions Division, St. Paul

Presented by Dr. Zhisheng Yun

09-01-2016

Efficient 3M PBS Enhancing Miniature Projection Optics

2. All Rights Reserved.2 September 2016© 3M 3M Confidential.

Outline

• 3M Giant Birefringence Multilayer Optical Film (MOF)

• 3M Polarization Beam Splitter (PBS)

• 3M Miniature Optical Systems of MM100, MM200, MM300 and

Tiny Projection Light Engine

• Optical Performance of Light Engine Summary

• Acknowledgment

3. All Rights Reserved.2 September 2016© 3M 3M Confidential.

Ideal Polarization Beam Splitter Multilayer Films

For high S-pol reflectivity: nx1>>nx2

For high transmission of P-pol and low

color: ny1 = ny2 = nz1 = nz2

Stretch Direction

z

nx1

nx2

xy

nz1

nz2

Incident light S-pol

P-pol

Reference: Michael F. Weber, Carl A. Stover, Larry R. Gilbert, Timothy J. Nevitt, Andrew J. Ouderkirket., Science 287 (5462), 2451-2456, (2000)

4. All Rights Reserved.2 September 2016© 3M 3M Confidential.

Birefringent Multilayer PBS Films

• Coextrude two thermally processable polymers

— One positively birefringent, the other, isotropic

• Create a variety of layer pair thicknesses to cover a range of

wavelengths

• Stretch to increase the refractive index of the birefringent layer

— “Ideal” orientation: the draw ratio (DR) of the non-stretch directions (Y and

Z) is equal to the inverse square root of the draw ratio in the stretch direction

(X)

DRxDRzDRy /1

5. All Rights Reserved.2 September 2016© 3M 3M Confidential.

Schematic of Stretching Multilayer Optical Films

Cast Web Pre-HeatStretch Output

Stretched Film

Edge trim

Trim

Tenter Chain

Set

VinVout= Vin

OVEN

x

y

Four major MOF manufacture steps:o Cast Webo Preheato Stretcho Setting

Reference: Martin E. Denker, Andrew T. Ruff, Kris Derks Invited Paper: “Advanced Polarizer Film for Improved Performance of Liquid Crystal Displays”, SID Symposium Digest of Technical Papers, Vol 37, Issue 1, p. 1528-1530, 2006.

6. All Rights Reserved.2 September 2016© 3M 3M Confidential.

3M PBS vs WG PBS

Light path within PBS

WG PBS 3M PBS

3M PBS vs Wire Grid PBS

Display with Linear Polarized Light

MirrorBonded QWP

WG 3M

7. All Rights Reserved.2 September 2016© 3M 3M Confidential.

3M PBS vs Wire Grid and MacNeille PBS

• Measurement data of 3M PBS vs Wire Grid and MacNeille PBS

• On-axis measurement results:

* MacNeille and wire grid PBS were from Throlabs and the part numbers are PBS251 and WPBS254.

Rs Ts Tp Rp Efficiency (Rs*Tp)

3M PBS 96.9% 0.09% 98.3% 0.10% 95.2%

McNeille* 93.1% 0.07% 96.6% 0.67% 89.9%

WireGride* 80.5% 0.02% 76.4% 3.99% 61.5%

8. All Rights Reserved.2 September 2016© 3M 3M Confidential.

Optical System of Light Engine MM100

Technologies developed in the MM100

optical system

• Low birefringence and curved PBS

• High efficiency with light recycle using with

3M reflective polarizer

• Unique Fresnel lens with Kohler illumination

configuration with system

Gen_1_Opcon_Solitaire1.3.ZMXConfiguration 1 of 1

Layout

8/22/2016Total Axial Length: 36.50326 mm

0 3 6 9 12 15 18 21 24 27 30

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

Spatial Frequency in cycles per mm

TS 0.00 mmTS -50.00 mm

TS -100.00 mmTS -175.00 mmTS -200.00 mm

TS -250.00 mm

Gen_1_Opcon_Solitaire1.3.ZMXConfiguration 1 of 1

Modulus of the OTF

Polychromatic Diffraction MTF

8/22/2016Data for 0.4600 to 0.6300 µm.Surface: Image

Reference: Ardashnikov, B., Duncan, J., Glinski,A., Grace, J., Pol, T., Phillips, B., Ridgeway, C., Rutherford, T., Shiba, E., VanOverloop, R., “A Mobile Projection Engine With A Multi-layer Reflective Polarizer Based PBS”, Proc. SID , 70.5L, 2008

9. All Rights Reserved.2 September 2016© 3M 3M Confidential.

Optical System of Light Engine MM200

Efficient Optical System Design

• Solid rod and ball lens for light collection and color mixing

• Aspheric illumination optics

High Efficiency Polarizing Beam Splitter (PBS)

• 3M Multilayer Optical Film Component

• High contrast

• High efficiency

• Low f/#

• Lensed PBS surface

High brightness LED Polarization recycling scheme

10. All Rights Reserved.2 September 2016© 3M 3M Confidential.

Optical System of Light Engine MM200

Projection Lens

PBS

LCOS ImagerIlluminator

Efficient Optical System Design• Light engine opto-mechanical system

• Cross section view of the illuminator collection and color mixing

Reference: Phillips, B., Grace, J., Yun, Z., Willett, S., Snively, D., Pol, T., Ardashnikov, B., O’Shea, G., “A High Efficiency Mobile Projection Engine Utilizing Color Sequential Illumination”, Proc. SID, 14.5, 2009

11. All Rights Reserved.2 September 2016© 3M 3M Confidential.

Optical System Of Light Engine MM300MM300 Technologies

• Polarization converter

• Lens array and relay optics

• Efficient 3M PBS technology

Blue

Red

Green

Polarization

converter

Lensarray

Relay lens

PBSField

lensProjection

lens group

0 5.6 11.2 16.8 22.4 28 33.6 39.2 44.8 50.4 56

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

Spatial Frequency in cycles per mm

TS 0.0000 mmTS 1.7489 mm

TS 3.2005 mmTS 4.1448 mmTS 5.2744 mm

TS 6.1072 mmTS 7.1100 mm

100Offset_0.42_PJlens_F1.62_VH001_Cyc449_Released.zmxConfiguration 1 of 3

Modulus of the OTF

Polychromatic Diffraction MTF

MM300 Projection Lens Cycle4498/22/2016Data for 0.4600 to 0.6150 µm.Surface: Image

100Offset_0.42_PJlens_F1.62_VH001_Cyc449_Released.zmxConfiguration 1 of 3

Layout

MM300 Projection Lens Cycle4498/22/2016Total Axial Length: 61.79562 mm

12. All Rights Reserved.2 September 2016© 3M 3M Confidential.

Optical System of Tiny Projector

Technologies in the tiny projector

optical system:

• High efficiency MOF

• Sophisticated PBS

• LED light collection and relay lens

• Light Re-cycle film used

• The system designed for color filter LCOS

imager with a white LED.

• The system also works for color sequential

LCOS imager with an additional color

mixing short rod.

Reference: Yun, Z., Ouderkirk, J. A., Tan, L. K., Tio, T. A., “Compact Illuminator”, US patent

application 2013/0063671

Projection

lens group

Imager

Field lens

LED collection

lens

Reflective

Polarizer

LED light

source

13. All Rights Reserved.2 September 2016© 3M 3M Confidential.

Comparison of 3M Pico Projection Optical Systems

Parameter MM100 MM200 MM300

Tiny Projector

(target specs)

Brightness at given

LED power (lm/W) 5.6lm/1W

8.0lm/1W

15.0lm/2.5W

8.5lm/W

68lm/8W

9.0lm/1W

30lm/4W

ANSI contrast 80 to 1 97 to 1 120 to 1 120 to 1

Resolution (Pixels) 640x480x3 640x480 1024x600 800x600

Modle Size (mm) 13.7x34.0x12.5 37.9x36x10.5 62.5x65x20.5 10.0x25.0x30.0

Weight (g) 21 14 70.5 9

14. All Rights Reserved.2 September 2016© 3M 3M Confidential.

15. All Rights Reserved.2 September 2016© 3M 3M Confidential.

Acknowledgements

• 3M Electronics Material Solutions Division, 3M Display Materials

Solutions Division and Electronics and Energy Laboratory

• Coauthors and contributors

• SPIE Organization Committee

Thank you and questions?