We provide a novel achromatic design in the illumination system for a mini projector with an LED light source. The lateral color aberration at the corners of the DMD active area can be reduced to 0.48 μm by our compact ATIR prism. The total prism size is 4091 mm³. The spot sizes at the corner and the edge are also controlled under 198 μm. Moreover, we use a light pipe for color uniformity at the center of the DMD active area. Under the two components for color uniformity, the Δu’ v’ is well controlled under 0.016 by a 20 mm length of light pipe. The illuminance uniformity at the active area of the DMD chip is higher than 92.8%. The optical efficiency of the light pipe is 94.1%.

© 2011 OSA

1. E. F. Schubert and J. K. Kim, “Solid-state light sources getting smart,” Science 308(5726), 1274–1278 (2005). [CrossRef] [PubMed]
2. Texas Instruments (TI), “DLP® Discovery Optics 101 Application Note,” http://focus.ti.com/lit/an/dlpa022/dlpa022.pdf .
3. H. Murat, D. Cuypers, H. De Smet, Y. Meuret, B. Van Giel, L. Bogaert, and H. Thienpont, “Two liquid crystal on silicon panel projector with efficient light-emitting diode illumination,” Opt. Eng. 46(12), 124002 (2007). [CrossRef]
4. C.-M. Chang and H.-P. D. Shieh, “Design of illumination and projection optics for projectors with single digital micromirror devices,” Appl. Opt. 39(19), 3202–3208 (2000). [CrossRef] [PubMed]
5. J.-W. Pan, S.-H. Tu, C.-M. Wang, and J.-Y. Chang, “High efficiency pocket-size projector with a compact projection lens and a light emitting diode-based light source system,” Appl. Opt. 47(19), 3406–3414 (2008). [CrossRef] [PubMed]
6. G. Harbers, M. Keuper, and S. Paolini, “Performance of high power LED illuminators in color sequential projection displays,” in Proceedings of Internal Display Workshop (IDW 2003).
7. G. Harbers, M. Keuper, and S. Paolini, “High power LED illuminators for data and video projector,” in Proceedings of Internal Display Workshop (IDW 2002).
8. M. H. Keuper, G. Harbers, and S. Paolini, “RGB LED Illuminator for Pocket-sized Projectors,” in International Symposium Digest of Technical Papers (SID ’04), 943–945 (2004).
9. M. Huseyin, C. Dieter, and D. S. Herbert, “Design of new collection systems for multi LED light engines,” Proc. SPIE 6196, 19604 (2006).
10. J. W. Pan, C. M. Wang, H. C. Lan, W. S. Sun, and J. Y. Chang, “Homogenized LED-illumination using microlens arrays for a pocket-sized projector,” Opt. Express 15(17), 10483–10491 (2007). [CrossRef] [PubMed]
11. E. H. Stupp and M. S. Brennesholtz, Projection Display, (Wiley, 2008).
12. J. W. Pan, C. M. Wang, W. S. Sun, and J. Y. Chang, “Portable digital micromirror device projector using a prism,” Appl. Opt. 46(22), 5097–5102 (2007). [CrossRef] [PubMed]
13. X. Zhao, Z.-L. Fang, J.-C. Cui, X. Zhang, and G.-G. Mu, “Illumination system using LED sources for pocket-size projectors,” Appl. Opt. 46(4), 522–526 (2007). [CrossRef] [PubMed]
14. Zemax, http://www.zemax.com/ .
15. Ohara Corporation, “Optical Glass Cross Reference Sheet, http://www.oharacorp.com/catalog.html .
16. G. W. Wyszecki and W. S. Stiles, Color Science: Concepts and Methods, Quantitative data and Formulae, (John Wiley & Sons, 1982).
17. OSRAM, “ LE_A_LE_T_LE_B_S2W,” http://catalog.osram-os.com/catalogue/catalogue.do?favOid=0000000400036fee03110023&act=showBookmark .
18. LightTools, http://www.opticalres.com/ .
19. W. J. Smith, “Prism and Mirror Systems,” in Modern Optical Engineering, 4th ed. (McGraw-Hill, 2008), pp. 619–621.

Appl. Opt.

• C.-M. Chang and H.-P. D. Shieh, “Design of illumination and projection optics for projectors with single digital micromirror devices,” Appl. Opt. 39(19), 3202–3208 (2000). [CrossRef] [PubMed]
• J.-W. Pan, S.-H. Tu, C.-M. Wang, and J.-Y. Chang, “High efficiency pocket-size projector with a compact projection lens and a light emitting diode-based light source system,” Appl. Opt. 47(19), 3406–3414 (2008). [CrossRef] [PubMed]
• J. W. Pan, C. M. Wang, W. S. Sun, and J. Y. Chang, “Portable digital micromirror device projector using a prism,” Appl. Opt. 46(22), 5097–5102 (2007). [CrossRef] [PubMed]
• X. Zhao, Z.-L. Fang, J.-C. Cui, X. Zhang, and G.-G. Mu, “Illumination system using LED sources for pocket-size projectors,” Appl. Opt. 46(4), 522–526 (2007). [CrossRef] [PubMed]

Opt. Eng.

• H. Murat, D. Cuypers, H. De Smet, Y. Meuret, B. Van Giel, L. Bogaert, and H. Thienpont, “Two liquid crystal on silicon panel projector with efficient light-emitting diode illumination,” Opt. Eng. 46(12), 124002 (2007). [CrossRef]

Opt. Express

• J. W. Pan, C. M. Wang, H. C. Lan, W. S. Sun, and J. Y. Chang, “Homogenized LED-illumination using microlens arrays for a pocket-sized projector,” Opt. Express 15(17), 10483–10491 (2007). [CrossRef] [PubMed]

Proc. SPIE

• M. Huseyin, C. Dieter, and D. S. Herbert, “Design of new collection systems for multi LED light engines,” Proc. SPIE 6196, 19604 (2006).

Science

• E. F. Schubert and J. K. Kim, “Solid-state light sources getting smart,” Science 308(5726), 1274–1278 (2005). [CrossRef] [PubMed]

Other

• Texas Instruments (TI), “DLP® Discovery Optics 101 Application Note,” http://focus.ti.com/lit/an/dlpa022/dlpa022.pdf .
• G. Harbers, M. Keuper, and S. Paolini, “Performance of high power LED illuminators in color sequential projection displays,” in Proceedings of Internal Display Workshop (IDW 2003).
• G. Harbers, M. Keuper, and S. Paolini, “High power LED illuminators for data and video projector,” in Proceedings of Internal Display Workshop (IDW 2002).
• M. H. Keuper, G. Harbers, and S. Paolini, “RGB LED Illuminator for Pocket-sized Projectors,” in International Symposium Digest of Technical Papers (SID ’04), 943–945 (2004).
• Zemax, http://www.zemax.com/ .
• Ohara Corporation, “Optical Glass Cross Reference Sheet, http://www.oharacorp.com/catalog.html .
• G. W. Wyszecki and W. S. Stiles, Color Science: Concepts and Methods, Quantitative data and Formulae, (John Wiley & Sons, 1982).
• OSRAM, “ LE_A_LE_T_LE_B_S2W,” http://catalog.osram-os.com/catalogue/catalogue.do?favOid=0000000400036fee03110023&act=showBookmark .
• LightTools, http://www.opticalres.com/ .
• W. J. Smith, “Prism and Mirror Systems,” in Modern Optical Engineering, 4th ed. (McGraw-Hill, 2008), pp. 619–621.
• E. H. Stupp and M. S. Brennesholtz, Projection Display, (Wiley, 2008).

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