Abstract

In this paper, we proposed a novel apparatus, which has very slim volume and can transfer light emitted from discrete LEDs into a uniform and ultra-collimated planar light source (UCPLS). This apparatus adopts the two-layer folded frame and two-stage CPC design so that thickness of the entire apparatus can be minimized; especially the feeder in the two-stage CPC design can greatly reduce the thickness of the CPC and make the light passing through the second-stage CPC become much more collimated. In addition, by side-by-side arrangement, a large-sized UCPLS can also be obtained. In our embodiment with an emitting area of the upper LGP of 280 mmX80 mm and a LED with optical flux of 8 lumens used as the light source, the performance according to the related simulation results shows as follows: angular FWHM of the resultant light emitted from the apparatus in the vertical and horizontal is 4.87 degrees and 24 degrees, respectively; spatial uniformity and total energy efficiency reach 84% and 69%, respectively; the average head-on luminance reaches up 5600 nit, yet this apparatus consumes just 60 mW. Furthermore, the results also demonstrate this design has potential to be applied to the product of 23 inches above while thickness of the entire apparatus is only 2.2 mm.

© 2013 Optical Society of America

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References

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  1. H. Mukawa, K. Akutsu, I. Matsumura, S. Nakano, T. Yoshida, M. Kuwahara, K. Aiki, and M. Ogawa, “A full color eyewear display using holographic planar waveguides,” SID Symp. Dig. Tech. Pap. 39, 89–92 (2008).
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    [Crossref]
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  8. P. C. Chen, H. H. Lin, C. H. Chen, C. H. Lee, and M. H. Lu, “Color separation system with angularly positioned light source module for pixelized backlighting,” Opt. Express 18(2), 645–655 (2010).
    [Crossref] [PubMed]
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    [Crossref]
  14. H. C. Cheng, J. Yan, T. Ishinabe, N. Sugiura, C. Y. Liu, T. H. Huang, C. Y. Tsai, C. H. Lin, and S. T. Wu, “Blue-phase liquid crystal displays with vertical field switching,” J. Disp. Technol. 8(2), 98–103 (2012).
    [Crossref]
  15. J. H. Lee, H. S. Lee, B. K. Lee, W. S. Choi, H. Y. Choi, and J. B. Yoon, “Simple liquid crystal display backlight unit comprising only a single-sheet micropatterned polydimethylsiloxane (PDMS) light-guide plate,” Opt. Lett. 32(18), 2665–2667 (2007).
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    [Crossref] [PubMed]
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    [Crossref] [PubMed]
  24. J. Chaves, W. Falicoff, O. Dross, J. C. Miñano, P. Benitez, and W. A. Parkyn, “Combination of light sources and light distribution using manifold optics,” Proc. SPIE 6338, 63380M (2006).

2013 (1)

2012 (3)

D. Grabovičkić, P. Benítez, J. C. Miñano, and J. Chaves, “LED backlight designs with the flow-line method,” Opt. Express 20(S1), A62–A68 (2012).
[Crossref] [PubMed]

A. Cameron, “Optical waveguide technology and its application in head mounted displays,” Proc. SPIE 8383, 83830E (2012).
[Crossref]

H. C. Cheng, J. Yan, T. Ishinabe, N. Sugiura, C. Y. Liu, T. H. Huang, C. Y. Tsai, C. H. Lin, and S. T. Wu, “Blue-phase liquid crystal displays with vertical field switching,” J. Disp. Technol. 8(2), 98–103 (2012).
[Crossref]

2011 (4)

W. H. Yang, H. H. Lin, C. J. Hsu, and Y. N. Pao, “LED coupler lens array for one dimensional collimating backlight,” IDW 11, 1399–1400 (2011).

Y. C. Kim, H. D. Im, M. G. Lee, and H. Y. Choi, “Directivity enhanced BLU for edge-type local dimming,” SID Symp. Dig. Tech. Pap. 42, 662–664 (2011).

K. Nakamura, T. Fuchida, K. Yamagata, A. Nishimura, T. Takita, and H. Takemoto, “Optical design of front diffuser for collimated backlight and front diffusing system,” IDW 11, 475–478 (2011).

J. W. Pan and C. W. Fan, “High luminance hybrid light guide plate for backlight module application,” Opt. Express 19(21), 20079–20087 (2011).
[Crossref] [PubMed]

2010 (2)

P. C. Chen, H. H. Lin, C. H. Chen, C. H. Lee, and M. H. Lu, “Color separation system with angularly positioned light source module for pixelized backlighting,” Opt. Express 18(2), 645–655 (2010).
[Crossref] [PubMed]

W. Mphepö, Y. P. Huang, P. Rudquist, and H. P. D. Shieh, “Digital micro hinge (DMH) based display pixels,” J. Disp. Technol. 6(4), 142–149 (2010).
[Crossref]

2009 (1)

2008 (1)

H. Mukawa, K. Akutsu, I. Matsumura, S. Nakano, T. Yoshida, M. Kuwahara, K. Aiki, and M. Ogawa, “A full color eyewear display using holographic planar waveguides,” SID Symp. Dig. Tech. Pap. 39, 89–92 (2008).

2007 (3)

2006 (3)

2004 (1)

Aiki, K.

H. Mukawa, K. Akutsu, I. Matsumura, S. Nakano, T. Yoshida, M. Kuwahara, K. Aiki, and M. Ogawa, “A full color eyewear display using holographic planar waveguides,” SID Symp. Dig. Tech. Pap. 39, 89–92 (2008).

Akutsu, K.

H. Mukawa, K. Akutsu, I. Matsumura, S. Nakano, T. Yoshida, M. Kuwahara, K. Aiki, and M. Ogawa, “A full color eyewear display using holographic planar waveguides,” SID Symp. Dig. Tech. Pap. 39, 89–92 (2008).

Aoyama, S.

Bathiche, S.

Benitez, P.

J. Chaves, W. Falicoff, O. Dross, J. C. Miñano, P. Benitez, and W. A. Parkyn, “Combination of light sources and light distribution using manifold optics,” Proc. SPIE 6338, 63380M (2006).

Benítez, P.

Cameron, A.

A. Cameron, “Optical waveguide technology and its application in head mounted displays,” Proc. SPIE 8383, 83830E (2012).
[Crossref]

Chaves, J.

D. Grabovičkić, P. Benítez, J. C. Miñano, and J. Chaves, “LED backlight designs with the flow-line method,” Opt. Express 20(S1), A62–A68 (2012).
[Crossref] [PubMed]

J. Chaves, W. Falicoff, O. Dross, J. C. Miñano, P. Benitez, and W. A. Parkyn, “Combination of light sources and light distribution using manifold optics,” Proc. SPIE 6338, 63380M (2006).

Chen, C. H.

Chen, P. C.

Cheng, H. C.

H. C. Cheng, J. Yan, T. Ishinabe, N. Sugiura, C. Y. Liu, T. H. Huang, C. Y. Tsai, C. H. Lin, and S. T. Wu, “Blue-phase liquid crystal displays with vertical field switching,” J. Disp. Technol. 8(2), 98–103 (2012).
[Crossref]

Chien, K. W.

Choi, H. Y.

Choi, W. S.

Cornelissen, H.

de Boer, D. K. G.

Dross, O.

J. Chaves, W. Falicoff, O. Dross, J. C. Miñano, P. Benitez, and W. A. Parkyn, “Combination of light sources and light distribution using manifold optics,” Proc. SPIE 6338, 63380M (2006).

Emerton, N.

Falicoff, W.

J. Chaves, W. Falicoff, O. Dross, J. C. Miñano, P. Benitez, and W. A. Parkyn, “Combination of light sources and light distribution using manifold optics,” Proc. SPIE 6338, 63380M (2006).

Fan, C. W.

Fuchida, T.

K. Nakamura, T. Fuchida, K. Yamagata, A. Nishimura, T. Takita, and H. Takemoto, “Optical design of front diffuser for collimated backlight and front diffusing system,” IDW 11, 475–478 (2011).

Funamoto, A.

Georgiou, A.

Grabovickic, D.

Hsu, C. J.

W. H. Yang, H. H. Lin, C. J. Hsu, and Y. N. Pao, “LED coupler lens array for one dimensional collimating backlight,” IDW 11, 1399–1400 (2011).

Huang, T. H.

H. C. Cheng, J. Yan, T. Ishinabe, N. Sugiura, C. Y. Liu, T. H. Huang, C. Y. Tsai, C. H. Lin, and S. T. Wu, “Blue-phase liquid crystal displays with vertical field switching,” J. Disp. Technol. 8(2), 98–103 (2012).
[Crossref]

Huang, Y. P.

W. Mphepö, Y. P. Huang, P. Rudquist, and H. P. D. Shieh, “Digital micro hinge (DMH) based display pixels,” J. Disp. Technol. 6(4), 142–149 (2010).
[Crossref]

Im, H. D.

Y. C. Kim, H. D. Im, M. G. Lee, and H. Y. Choi, “Directivity enhanced BLU for edge-type local dimming,” SID Symp. Dig. Tech. Pap. 42, 662–664 (2011).

Imanaka, K.

Ishinabe, T.

H. C. Cheng, J. Yan, T. Ishinabe, N. Sugiura, C. Y. Liu, T. H. Huang, C. Y. Tsai, C. H. Lin, and S. T. Wu, “Blue-phase liquid crystal displays with vertical field switching,” J. Disp. Technol. 8(2), 98–103 (2012).
[Crossref]

Kim, Y. C.

Y. C. Kim, H. D. Im, M. G. Lee, and H. Y. Choi, “Directivity enhanced BLU for edge-type local dimming,” SID Symp. Dig. Tech. Pap. 42, 662–664 (2011).

Kollin, J.

Kuwahara, M.

H. Mukawa, K. Akutsu, I. Matsumura, S. Nakano, T. Yoshida, M. Kuwahara, K. Aiki, and M. Ogawa, “A full color eyewear display using holographic planar waveguides,” SID Symp. Dig. Tech. Pap. 39, 89–92 (2008).

Kwon, O. J.

Lanier, J.

Large, T.

Lee, B. K.

Lee, C. H.

Lee, H. S.

Lee, J. H.

Lee, M. G.

Y. C. Kim, H. D. Im, M. G. Lee, and H. Y. Choi, “Directivity enhanced BLU for edge-type local dimming,” SID Symp. Dig. Tech. Pap. 42, 662–664 (2011).

Lin, C. H.

H. C. Cheng, J. Yan, T. Ishinabe, N. Sugiura, C. Y. Liu, T. H. Huang, C. Y. Tsai, C. H. Lin, and S. T. Wu, “Blue-phase liquid crystal displays with vertical field switching,” J. Disp. Technol. 8(2), 98–103 (2012).
[Crossref]

Lin, H. H.

W. H. Yang, H. H. Lin, C. J. Hsu, and Y. N. Pao, “LED coupler lens array for one dimensional collimating backlight,” IDW 11, 1399–1400 (2011).

P. C. Chen, H. H. Lin, C. H. Chen, C. H. Lee, and M. H. Lu, “Color separation system with angularly positioned light source module for pixelized backlighting,” Opt. Express 18(2), 645–655 (2010).
[Crossref] [PubMed]

Liu, C. Y.

H. C. Cheng, J. Yan, T. Ishinabe, N. Sugiura, C. Y. Liu, T. H. Huang, C. Y. Tsai, C. H. Lin, and S. T. Wu, “Blue-phase liquid crystal displays with vertical field switching,” J. Disp. Technol. 8(2), 98–103 (2012).
[Crossref]

Lu, M. H.

MacCrann, N.

Matsumura, I.

H. Mukawa, K. Akutsu, I. Matsumura, S. Nakano, T. Yoshida, M. Kuwahara, K. Aiki, and M. Ogawa, “A full color eyewear display using holographic planar waveguides,” SID Symp. Dig. Tech. Pap. 39, 89–92 (2008).

Miñano, J. C.

D. Grabovičkić, P. Benítez, J. C. Miñano, and J. Chaves, “LED backlight designs with the flow-line method,” Opt. Express 20(S1), A62–A68 (2012).
[Crossref] [PubMed]

J. Chaves, W. Falicoff, O. Dross, J. C. Miñano, P. Benitez, and W. A. Parkyn, “Combination of light sources and light distribution using manifold optics,” Proc. SPIE 6338, 63380M (2006).

Mphepö, W.

W. Mphepö, Y. P. Huang, P. Rudquist, and H. P. D. Shieh, “Digital micro hinge (DMH) based display pixels,” J. Disp. Technol. 6(4), 142–149 (2010).
[Crossref]

Mukawa, H.

H. Mukawa, K. Akutsu, I. Matsumura, S. Nakano, T. Yoshida, M. Kuwahara, K. Aiki, and M. Ogawa, “A full color eyewear display using holographic planar waveguides,” SID Symp. Dig. Tech. Pap. 39, 89–92 (2008).

Nakamura, K.

K. Nakamura, T. Fuchida, K. Yamagata, A. Nishimura, T. Takita, and H. Takemoto, “Optical design of front diffuser for collimated backlight and front diffusing system,” IDW 11, 475–478 (2011).

Nakano, S.

H. Mukawa, K. Akutsu, I. Matsumura, S. Nakano, T. Yoshida, M. Kuwahara, K. Aiki, and M. Ogawa, “A full color eyewear display using holographic planar waveguides,” SID Symp. Dig. Tech. Pap. 39, 89–92 (2008).

Nishimura, A.

K. Nakamura, T. Fuchida, K. Yamagata, A. Nishimura, T. Takita, and H. Takemoto, “Optical design of front diffuser for collimated backlight and front diffusing system,” IDW 11, 475–478 (2011).

Ogawa, M.

H. Mukawa, K. Akutsu, I. Matsumura, S. Nakano, T. Yoshida, M. Kuwahara, K. Aiki, and M. Ogawa, “A full color eyewear display using holographic planar waveguides,” SID Symp. Dig. Tech. Pap. 39, 89–92 (2008).

Pan, J. W.

Pao, Y. N.

W. H. Yang, H. H. Lin, C. J. Hsu, and Y. N. Pao, “LED coupler lens array for one dimensional collimating backlight,” IDW 11, 1399–1400 (2011).

Park, S. R.

Parkyn, W. A.

J. Chaves, W. Falicoff, O. Dross, J. C. Miñano, P. Benitez, and W. A. Parkyn, “Combination of light sources and light distribution using manifold optics,” Proc. SPIE 6338, 63380M (2006).

Rudquist, P.

W. Mphepö, Y. P. Huang, P. Rudquist, and H. P. D. Shieh, “Digital micro hinge (DMH) based display pixels,” J. Disp. Technol. 6(4), 142–149 (2010).
[Crossref]

Shieh, H. P. D.

Shin, D.

Song, S. H.

Sugiura, N.

H. C. Cheng, J. Yan, T. Ishinabe, N. Sugiura, C. Y. Liu, T. H. Huang, C. Y. Tsai, C. H. Lin, and S. T. Wu, “Blue-phase liquid crystal displays with vertical field switching,” J. Disp. Technol. 8(2), 98–103 (2012).
[Crossref]

Takemoto, H.

K. Nakamura, T. Fuchida, K. Yamagata, A. Nishimura, T. Takita, and H. Takemoto, “Optical design of front diffuser for collimated backlight and front diffusing system,” IDW 11, 475–478 (2011).

Takita, T.

K. Nakamura, T. Fuchida, K. Yamagata, A. Nishimura, T. Takita, and H. Takemoto, “Optical design of front diffuser for collimated backlight and front diffusing system,” IDW 11, 475–478 (2011).

Travis, A.

Tsai, C. Y.

H. C. Cheng, J. Yan, T. Ishinabe, N. Sugiura, C. Y. Liu, T. H. Huang, C. Y. Tsai, C. H. Lin, and S. T. Wu, “Blue-phase liquid crystal displays with vertical field switching,” J. Disp. Technol. 8(2), 98–103 (2012).
[Crossref]

Urbach, H. P.

Wu, S. T.

H. C. Cheng, J. Yan, T. Ishinabe, N. Sugiura, C. Y. Liu, T. H. Huang, C. Y. Tsai, C. H. Lin, and S. T. Wu, “Blue-phase liquid crystal displays with vertical field switching,” J. Disp. Technol. 8(2), 98–103 (2012).
[Crossref]

Xu, M.

Yamagata, K.

K. Nakamura, T. Fuchida, K. Yamagata, A. Nishimura, T. Takita, and H. Takemoto, “Optical design of front diffuser for collimated backlight and front diffusing system,” IDW 11, 475–478 (2011).

Yan, J.

H. C. Cheng, J. Yan, T. Ishinabe, N. Sugiura, C. Y. Liu, T. H. Huang, C. Y. Tsai, C. H. Lin, and S. T. Wu, “Blue-phase liquid crystal displays with vertical field switching,” J. Disp. Technol. 8(2), 98–103 (2012).
[Crossref]

Yang, W. H.

W. H. Yang, H. H. Lin, C. J. Hsu, and Y. N. Pao, “LED coupler lens array for one dimensional collimating backlight,” IDW 11, 1399–1400 (2011).

Yoon, J. B.

Yoshida, T.

H. Mukawa, K. Akutsu, I. Matsumura, S. Nakano, T. Yoshida, M. Kuwahara, K. Aiki, and M. Ogawa, “A full color eyewear display using holographic planar waveguides,” SID Symp. Dig. Tech. Pap. 39, 89–92 (2008).

Appl. Opt. (3)

IDW (2)

W. H. Yang, H. H. Lin, C. J. Hsu, and Y. N. Pao, “LED coupler lens array for one dimensional collimating backlight,” IDW 11, 1399–1400 (2011).

K. Nakamura, T. Fuchida, K. Yamagata, A. Nishimura, T. Takita, and H. Takemoto, “Optical design of front diffuser for collimated backlight and front diffusing system,” IDW 11, 475–478 (2011).

J. Disp. Technol. (2)

W. Mphepö, Y. P. Huang, P. Rudquist, and H. P. D. Shieh, “Digital micro hinge (DMH) based display pixels,” J. Disp. Technol. 6(4), 142–149 (2010).
[Crossref]

H. C. Cheng, J. Yan, T. Ishinabe, N. Sugiura, C. Y. Liu, T. H. Huang, C. Y. Tsai, C. H. Lin, and S. T. Wu, “Blue-phase liquid crystal displays with vertical field switching,” J. Disp. Technol. 8(2), 98–103 (2012).
[Crossref]

Opt. Express (7)

Opt. Lett. (1)

Proc. SPIE (2)

A. Cameron, “Optical waveguide technology and its application in head mounted displays,” Proc. SPIE 8383, 83830E (2012).
[Crossref]

J. Chaves, W. Falicoff, O. Dross, J. C. Miñano, P. Benitez, and W. A. Parkyn, “Combination of light sources and light distribution using manifold optics,” Proc. SPIE 6338, 63380M (2006).

SID Symp. Dig. Tech. Pap. (2)

H. Mukawa, K. Akutsu, I. Matsumura, S. Nakano, T. Yoshida, M. Kuwahara, K. Aiki, and M. Ogawa, “A full color eyewear display using holographic planar waveguides,” SID Symp. Dig. Tech. Pap. 39, 89–92 (2008).

Y. C. Kim, H. D. Im, M. G. Lee, and H. Y. Choi, “Directivity enhanced BLU for edge-type local dimming,” SID Symp. Dig. Tech. Pap. 42, 662–664 (2011).

Other (5)

T. Levola, “Color distribution in exit pupil expanders,” US patent 8254031 (2012).

LGD, “Stereoscopic display device using electrically-driven liquid crystal lens,” US patent 7855756 (2010).

L. Pyayt, G. K. Starkweather, and M. J. Sinclair, “One telescope per pixel,” OSA CLEO (2010).

I. B. M. Corporation, “Light guide apparatus, a backlight apparatus and a liquid crystal display apparatus,” US patent 6667782Bl (2003).

Nanogate Advanced Materials, “Illuminating device,” US patent 7682062 (2010).

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Figures (6)

Fig. 1
Fig. 1

Illustration of the feeder used in DSLF CPC design: (a) perspective view; (b) front view (not drawn to scale).

Fig. 2
Fig. 2

Illustration of the component layout in the lower layer of the apparatus.

Fig. 3
Fig. 3

Cross-section of the coupling prism.

Fig. 4
Fig. 4

Schematic illustration of the entire apparatus: (a) perspective view; (b) front view (not drawn to scale).

Fig. 5
Fig. 5

The effect of the light-mixing plate on light distribution: (a) horizontal spatial distribution; (b) angular distribution.

Fig. 6
Fig. 6

Energy distribution of the light emitted from the upper LGP: (a) angular distribution; (b) spatial distribution.

Tables (3)

Tables Icon

Table 1 Coupling efficiency for the various first-stage CPC designs.

Tables Icon

Table 2 Simulation analysis for various length of second-stage CPC designs.

Tables Icon

Table 3 Energy efficiency for the components of the apparatus.

Equations (2)

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

A 1 A 2 = n 2 sin θ 2 n 1 sin θ 1 ,
A 1 A 2 = ( n 2 sin θ 2 ) 2 ( n 1 sin θ 1 ) 2 .

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