Abstract

We proposed a design for a LASER pico-projector with a low speckle contrast value and high contrast ratio that maintains system efficiency. The method for speckle contrast reduction utilizes two diffusers and a Voice Coil Motor (VCM) oscillator. The two different diffusers for a high contrast ratio and high system efficiency can be divided into two categories. In Category 1, the speckle contrast value can be decreased to 2.80% by using a circular symmetric diffuser. At the same time, the full-on/full-off (FO:FO) contrast ratio can be maintained within 1200:1-1300:1, but the system efficiency decreases 1.50%. In Category 2, the speckle contrast value can be reduced to 6.50% by using an elliptically scattering diffuser. At the same time, the FO:FO contrast ratio can be maintained within 1300:1-1400:1, and the system efficiency decreases by only 1.00%.

© 2014 Optical Society of America

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References

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2013 (1)

2012 (3)

2011 (1)

K. Ishida, M. Kurashige, T. Takanokura, Y. Ohyagi, M. Watanabe, “Laser Projection System with Variable Speckle Generator,” SID 42, 424–427 (2011).

2010 (2)

2009 (1)

2008 (2)

V. Yurlov, A. Lapchuk, S. Yun, J. Song, H. Yang, “Speckle suppression in scanning laser display,” Appl. Opt. 47(2), 179–187 (2008).
[CrossRef] [PubMed]

A. Furukawa, N. Ohse, Y. Sato, D. Imanishi, K. Wakabayashi, S. Ito, K. Tamamura, S. Hirata, “Effective speckle reduction in laser projection displays,” Proc. SPIE 6911, 69110 (2008).
[CrossRef]

2007 (2)

2003 (1)

J. W. Bowron, R. P. Jonas, “Off-axis illumination design for DMD system,” Proc. SPIE 5186, 72–82 (2003).
[CrossRef]

2000 (1)

L. Wang, T. Tschudi, M. Boeddinghaus, A. Elbert, T. Halldo’rsson, P. Pe’tursson, “Speckle reduction in laser projections with ultrasonic waves,” Opt. Eng. 39(6), 1659–1664 (2000).

1976 (1)

Akram, M. N.

Allen, G.

Bastian, G.

Boeddinghaus, M.

L. Wang, T. Tschudi, M. Boeddinghaus, A. Elbert, T. Halldo’rsson, P. Pe’tursson, “Speckle reduction in laser projections with ultrasonic waves,” Opt. Eng. 39(6), 1659–1664 (2000).

Bowron, J. W.

J. W. Bowron, R. P. Jonas, “Off-axis illumination design for DMD system,” Proc. SPIE 5186, 72–82 (2003).
[CrossRef]

Cao, H.

Chang, J. Y.

Chen, C. H.

Chen, X.

Dong, H.

Duan, J.

Dufresne, E. R.

Elbert, A.

L. Wang, T. Tschudi, M. Boeddinghaus, A. Elbert, T. Halldo’rsson, P. Pe’tursson, “Speckle reduction in laser projections with ultrasonic waves,” Opt. Eng. 39(6), 1659–1664 (2000).

Fang, Q.

Furukawa, A.

A. Furukawa, N. Ohse, Y. Sato, D. Imanishi, K. Wakabayashi, S. Ito, K. Tamamura, S. Hirata, “Effective speckle reduction in laser projection displays,” Proc. SPIE 6911, 69110 (2008).
[CrossRef]

Goodman, J. W.

Halldo’rsson, T.

L. Wang, T. Tschudi, M. Boeddinghaus, A. Elbert, T. Halldo’rsson, P. Pe’tursson, “Speckle reduction in laser projections with ultrasonic waves,” Opt. Eng. 39(6), 1659–1664 (2000).

Hirata, S.

A. Furukawa, N. Ohse, Y. Sato, D. Imanishi, K. Wakabayashi, S. Ito, K. Tamamura, S. Hirata, “Effective speckle reduction in laser projection displays,” Proc. SPIE 6911, 69110 (2008).
[CrossRef]

Imanishi, D.

A. Furukawa, N. Ohse, Y. Sato, D. Imanishi, K. Wakabayashi, S. Ito, K. Tamamura, S. Hirata, “Effective speckle reduction in laser projection displays,” Proc. SPIE 6911, 69110 (2008).
[CrossRef]

Ishida, K.

K. Ishida, M. Kurashige, T. Takanokura, Y. Ohyagi, M. Watanabe, “Laser Projection System with Variable Speckle Generator,” SID 42, 424–427 (2011).

K. Ishida, M. Kurashige, T. Takanokura, Y. Ohyagi, M. Watanabe, “Despeckling method with variable speckle generator utilizing photopolymer film,” Proc IDW2, 1471–1474 (2010).

Ito, S.

A. Furukawa, N. Ohse, Y. Sato, D. Imanishi, K. Wakabayashi, S. Ito, K. Tamamura, S. Hirata, “Effective speckle reduction in laser projection displays,” Proc. SPIE 6911, 69110 (2008).
[CrossRef]

Jonas, R. P.

J. W. Bowron, R. P. Jonas, “Off-axis illumination design for DMD system,” Proc. SPIE 5186, 72–82 (2003).
[CrossRef]

Kartashov, V.

Kurashige, M.

K. Ishida, M. Kurashige, T. Takanokura, Y. Ohyagi, M. Watanabe, “Laser Projection System with Variable Speckle Generator,” SID 42, 424–427 (2011).

K. Ishida, M. Kurashige, T. Takanokura, Y. Ohyagi, M. Watanabe, “Despeckling method with variable speckle generator utilizing photopolymer film,” Proc IDW2, 1471–1474 (2010).

Lan, H. C.

Lapchuk, A.

Lemmer, U.

Liu, Y.

Lu, Z.

M. Sun, Z. Lu, “Speckle suppression with a rotating light pipe,” Opt. Eng. 49(2), 024202 (2010).
[CrossRef]

Mehta, D. S.

Nafarrate, A. B.

Naik, D. N.

Norton, R. E.

Ohse, N.

A. Furukawa, N. Ohse, Y. Sato, D. Imanishi, K. Wakabayashi, S. Ito, K. Tamamura, S. Hirata, “Effective speckle reduction in laser projection displays,” Proc. SPIE 6911, 69110 (2008).
[CrossRef]

Ohyagi, Y.

K. Ishida, M. Kurashige, T. Takanokura, Y. Ohyagi, M. Watanabe, “Laser Projection System with Variable Speckle Generator,” SID 42, 424–427 (2011).

K. Ishida, M. Kurashige, T. Takanokura, Y. Ohyagi, M. Watanabe, “Despeckling method with variable speckle generator utilizing photopolymer film,” Proc IDW2, 1471–1474 (2010).

Ouyang, G.

Pan, J. W.

Pe’tursson, P.

L. Wang, T. Tschudi, M. Boeddinghaus, A. Elbert, T. Halldo’rsson, P. Pe’tursson, “Speckle reduction in laser projections with ultrasonic waves,” Opt. Eng. 39(6), 1659–1664 (2000).

Rawson, E. G.

Redding, B.

Riechert, F.

Sato, Y.

A. Furukawa, N. Ohse, Y. Sato, D. Imanishi, K. Wakabayashi, S. Ito, K. Tamamura, S. Hirata, “Effective speckle reduction in laser projection displays,” Proc. SPIE 6911, 69110 (2008).
[CrossRef]

Shi, A.

Singh, R. K.

Song, J.

Sun, M.

M. Sun, Z. Lu, “Speckle suppression with a rotating light pipe,” Opt. Eng. 49(2), 024202 (2010).
[CrossRef]

Sun, W. S.

Takanokura, T.

K. Ishida, M. Kurashige, T. Takanokura, Y. Ohyagi, M. Watanabe, “Laser Projection System with Variable Speckle Generator,” SID 42, 424–427 (2011).

K. Ishida, M. Kurashige, T. Takanokura, Y. Ohyagi, M. Watanabe, “Despeckling method with variable speckle generator utilizing photopolymer film,” Proc IDW2, 1471–1474 (2010).

Takeda, M.

Tamamura, K.

A. Furukawa, N. Ohse, Y. Sato, D. Imanishi, K. Wakabayashi, S. Ito, K. Tamamura, S. Hirata, “Effective speckle reduction in laser projection displays,” Proc. SPIE 6911, 69110 (2008).
[CrossRef]

Tong, Z.

Tschudi, T.

L. Wang, T. Tschudi, M. Boeddinghaus, A. Elbert, T. Halldo’rsson, P. Pe’tursson, “Speckle reduction in laser projections with ultrasonic waves,” Opt. Eng. 39(6), 1659–1664 (2000).

Wakabayashi, K.

A. Furukawa, N. Ohse, Y. Sato, D. Imanishi, K. Wakabayashi, S. Ito, K. Tamamura, S. Hirata, “Effective speckle reduction in laser projection displays,” Proc. SPIE 6911, 69110 (2008).
[CrossRef]

Wang, C. M.

Wang, L.

L. Wang, T. Tschudi, M. Boeddinghaus, A. Elbert, T. Halldo’rsson, P. Pe’tursson, “Speckle reduction in laser projections with ultrasonic waves,” Opt. Eng. 39(6), 1659–1664 (2000).

Wang, R.

Watanabe, M.

K. Ishida, M. Kurashige, T. Takanokura, Y. Ohyagi, M. Watanabe, “Laser Projection System with Variable Speckle Generator,” SID 42, 424–427 (2011).

K. Ishida, M. Kurashige, T. Takanokura, Y. Ohyagi, M. Watanabe, “Despeckling method with variable speckle generator utilizing photopolymer film,” Proc IDW2, 1471–1474 (2010).

Yang, H.

Yao, P. H.

Yun, S.

Yurlov, V.

Zhang, Y.

Appl. Opt. (7)

J. Opt. Soc. Am. (1)

Opt. Eng. (2)

M. Sun, Z. Lu, “Speckle suppression with a rotating light pipe,” Opt. Eng. 49(2), 024202 (2010).
[CrossRef]

L. Wang, T. Tschudi, M. Boeddinghaus, A. Elbert, T. Halldo’rsson, P. Pe’tursson, “Speckle reduction in laser projections with ultrasonic waves,” Opt. Eng. 39(6), 1659–1664 (2000).

Opt. Express (2)

Proc. SPIE (2)

J. W. Bowron, R. P. Jonas, “Off-axis illumination design for DMD system,” Proc. SPIE 5186, 72–82 (2003).
[CrossRef]

A. Furukawa, N. Ohse, Y. Sato, D. Imanishi, K. Wakabayashi, S. Ito, K. Tamamura, S. Hirata, “Effective speckle reduction in laser projection displays,” Proc. SPIE 6911, 69110 (2008).
[CrossRef]

SID (1)

K. Ishida, M. Kurashige, T. Takanokura, Y. Ohyagi, M. Watanabe, “Laser Projection System with Variable Speckle Generator,” SID 42, 424–427 (2011).

Other (15)

K. Ishida, M. Kurashige, T. Takanokura, Y. Ohyagi, M. Watanabe, “Despeckling method with variable speckle generator utilizing photopolymer film,” Proc IDW2, 1471–1474 (2010).

B. Lippey and W. Beck, “SPECKLE REDUCTION METHOD,” US Patent 0170110 Jul. 6 (2012).

J. M. Florence, “Speckle-free display system using coherence light,” US Patent 5313479 (1994).

Mightex system, CCD camera, Website http://www.mightexsystems.com/family_info.php?cPath=1_251_191_36_38&categories_id=38

Luminit, Light Shaping Diffusers, Website:

http://www.luminitco.com/sites/default/files/LSD_Tech_Datasht_5_21_12_lo_0.pdf

J. W. Goodman, Speckle Phenomena in Optics: Theory and Applications (Roberts 2007).

W. J. Smith, Modern Optical Engineering, 4th ed. (McGraw Hill, 2007).

C. K. Liu, C. C. Liao, K. Wang, and Y. J. Chen, “Pico Projector with Anamorphic Illumination System,” IDW. 1451-1453 (2010).

Computar, objective lens, Website http://computarganz.com/product_search.cfm?catalog_id=1&do_search=1&model_number=T4Z2813CS-IR

S. Sinzinger and J. Jahns, Microoptics (John Wiley, 2003).

W. Singer, M. Totzeck, and H. Groo, Handbook of Optical Systems Volume 2: Physical Image Formation (Wiley, 2006).

Texas Instruments (TI), 0.3” DMD, Website: http://www.ti.com/lit/ds/symlink/dlp3000.pdf

I. S.-S. A. Radiant Zemax, Website: http://www.radiantzemax.com/measurement-systems/imaging-sphere/is-sa

M. S. Brennesholtz and E. H. Stupp, Projection Displays Second Edition (2008).

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Figures (11)

Fig. 1
Fig. 1

Sketch of the experiment setup.

Fig. 2
Fig. 2

Layout of the LASER pico-projector.

Fig. 3
Fig. 3

Dependence of the vibrating amplitude of the VCM oscillator on the oscillator’s frequency.

Fig. 4
Fig. 4

When the second diffuser is a circular symmetric diffuser, the vibrating mode can be divided into two modes: (a) 30X30V, 30X30; (b) 30X30H, 30X30.

Fig. 5
Fig. 5

The dependence of the speckle contrast value on the VCM oscillator frequency for different diffusers: (a) the first diffuser is 10X10 with a series of second diffusers; (b) first diffuser is 30X30 with a series of second diffusers.

Fig. 6
Fig. 6

When the second diffuser is an elliptically scattering diffuser, the vibrating mode can be divided into four types: (a)30X30V, 80X20; (b)30X30V, 20X80; (c)30X30H, 80X20; (d)30X30H, 20X80.

Fig. 7
Fig. 7

The dependence of the speckle contrast on the VCM oscillation frequency for different second diffusers: (a) second diffuser is 30X5 with different vibrating modes; (b) second diffuser is 50X10 with different vibrating modes; (c) second diffuser is 80X20 with different vibrating modes.

Fig. 8
Fig. 8

The relationship between the cone angle of the light pipe system and the cone angle of the relay lens system in angular space.

Fig. 9
Fig. 9

Test image results: (a) only first 30X30 diffuser without vibrating VCM oscillation; (b) “30X30V, 30X30”with a VCM oscillator frequency of 100Hz.

Fig. 10
Fig. 10

The relationship between the projection lens stop, cone angle of illumination system and the asymmetric stop for: (a) circular cone angle distribution; (b) parallel type cone angle distribution (30X30, 5X30); (c) perpendicular cone angle distribution (30X30, 30X5).

Fig. 11
Fig. 11

The relationship between system efficiency and the FO:FO contrast ratio for different asymmetric stop positions and different second diffusers: (a) circular symmetric second diffuser; (b) elliptically scattering second diffuser.

Tables (2)

Tables Icon

Table 1 Number of Reflections with the First 10X10 Diffuser and the First 30X30 Diffuser with a 12mm Long Light Pipe

Tables Icon

Table 2 The Relationship Between the Relay System Efficiency, the Lowest Speckle Contrast Value, and the Highest FO:FO Contrast Ratio for Different Diffuser Types

Equations (2)

Equations on this page are rendered with MathJax. Learn more.

C= < I 2 ><I > 2 <I> ×100%
FO:FO contrast ratio = L(on state) L(off state)

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