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Studies on light extraction design of white LEDs with high luminous efficiency and uniformity

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Abstract

In this paper a new planar optical system with patterned phosphor-layer structures is demonstrated. The phosphor film herein acts as a wavelength converter and a light diffuser simultaneously. The patterned structures can increase the depth of blue ray intrude into phosphor film. The absorption rate of blue ray and the utilization efficiency of phosphors are increased. So the luminous efficiency is improved. Given different patterns on the phosphor layer surface, the optical properties of the proposed optical system, light-emitting efficiency and uniformity, are studied. Eventually, an average irradiance of 58.372 W/m2 and a more appropriate color temperature of the lighting source for high quality optical system were achieved. Phosphor layer of flat and part-etched pattern were compared in irradiance. The result validates part-etched phosphor-layer produce 2.57 % higher average irradiance than flat phosphor-layer. The patterned area on phosphor-layer can increase the extraction efficiency of blue rays at periphery part, the uniformity of correlated color temperature (CCT) at periphery area is significantly improved, the light candela distribution of output light are adjusted by the patterns, so the illumination uniformity of planar optical system is adjusted. Finally, the yellow circle phenomenon of planar optical system is effectively improved by the given patterns. Then it will be utilized in high quality planar optical system.

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References

  1. S. Ye, et al. Phosphors in phosphor-converted white light-emitting diodes: Recent advances in materials, techniques and properties. Mater. Sci. Eng.: R: Rep. 71, 1–34 (2010)

  2. H. C. Chen, et al., Improvement of lumen efficiency in white light-emitting diodes with air-gap embedded package. Microelectron. Reliab. 52, 933–936 (2012)

  3. H. Hsin-Tao, et al., Planar Lighting System Using Array of Blue LEDs to Excite Yellow Remote Phosphor Film. Disp. Technol. J. 7, 44–51 (2011)

  4. H.-C. Kuo et al., Patterned structure of remote phosphor for phosphor-converted white LEDs. Opt. Express 19, A930–A936 (2011)

    Article  ADS  Google Scholar 

  5. H.C. Chen et al., A novel randomly textured phosphor structure for highly efficient white light-emitting diodes. Nanoscale Res. Lett. 7, 1–5 (2012)

    Article  MATH  Google Scholar 

  6. L. Ming-Te et al., Ring Remote Phosphor Structure for Phosphor-Converted White LEDs. Phot. Technol. Lett. IEEE 22, 574–576 (2010)

    Article  ADS  Google Scholar 

  7. C. Kuo-Ju, et al., High uniformity of remote phosphor structure by ZrO2 nano-particles for white LEDs. in Communications and Photonics Conference (ACP), 2012 Asia, (2012), pp. 1–3

  8. S.-C. Park et al., Luminous efficiency of open remote phosphor-converted white-light-emitting diodes. J. Kor. Phys. Soc. 60, 1191–1195 (2012)

    Article  ADS  Google Scholar 

  9. H.C. Chen et al., Improvement of lumen efficiency in white light-emitting diodes with air-gap embedded package. Microelectron. Reliab. 52, 933–936 (2012)

    Article  Google Scholar 

  10. K.-J. Chen et al., Enhanced Luminous efficiency of WLEDs using a dual-layer structure of the remote phosphor package. J. Lightwave Technol. 31, 1941–1945 (2013)

    Article  ADS  Google Scholar 

  11. R. Yu et al., Effect of the phosphor geometry on the luminous flux of phosphor-converted light-emitting diodes. IEEE Photon. Technol. Lett. 22, 1765–1767 (2010)

    Article  ADS  Google Scholar 

  12. G. Rongfeng, et al., Preparation and performance of white LED packaged YAG phosphor. in Electronic Packaging Technology & High Density Packaging, 2009. ICEPT-HDP ‘09. International Conference on, pp. 786–789 (2009)

  13. T. Chun-Chin et al., Investigation of Ce:YAG Doping Effect on Thermal Aging for High-Power Phosphor-Converted White-Light-Emitting Diodes. Dev Mater. Reliab. IEEE Trans. 9, 367–371 (2009)

    Article  Google Scholar 

  14. L. Zong-Yuan, et al., Effects of YAG: Ce Phosphor Particle Size on Luminous Flux and Angular Color Uniformity of Phosphor-Converted White LEDs. Disp. Technol. J. 8, 329–335 (2012)

  15. W. Heller, Remarks on Refractive Index Mixture Rules. J. Phys. Chem. 69, 1123–1129, 2013/03/11 1965

  16. L. Zong-Yuan, et al., Studies on Optical Consistency of White LEDs Affected by Phosphor Thickness and Concentration Using Optical Simulation. Compon. Packag. Technol. IEEE Trans. 33, 680–687

  17. Z. Liu, et al., Effects of phosphor's location on LED packaging performance. Pudong, Shanghai, China, 2008, pp. China Electronics Packaging Society CEPS, China Inst. Electronics; Fudan University; The Component, Packaging, Manuf. Technol. Soc. IEEE (IEEE-CPMT); The International Microelectronics and Packaging Society (IMAPS)

  18. M. Zachau, et al., Phosphors for solid state lighting. pp. 691010–691010, (2008)

  19. D. Feng et al., Novel integrated light-guide plates for liquid crystal display backlight. J. Opt. A Pure Appl. Opt. 7, 111–117 (2005)

    Article  ADS  Google Scholar 

  20. Y.-H. Lu and C.-H. Tien, A novel direct-LED-backlight unit using grooved hexagonal light-guide plate. (San Francisco, CA, United states, 2006), pp. 1488–1491

  21. J.K. Kim et al., Strongly enhanced phosphor efficiency in GaInN white light-emitting diodes using remote phosphor configuration and diffuse reflector cup. Jpn. J. Appl. Phys. 2 Lett. 44, L649–L651 (2005)

    Article  Google Scholar 

  22. R. Hu et al., Comprehensive study on the transmitted and reflected light through the phosphor layer in light-emitting diode packages. IEEE/OSA J. Disp. Technol. 9, 447–452 (2013)

    Article  ADS  Google Scholar 

  23. B. Won Park et al., White-electroluminescent device with horizontally patterned blue/yellow phosphor-layer structure. J. Lumin. 127, 531–533 (2007)

    Article  Google Scholar 

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Acknowledgments

This work was supported by Zhejiang Science and Technology creation team for LED illuminating (Grant No.2012R10020-15) and Hangzhou Science and Technology Program (Grant No. 20110533B33).

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Authors and Affiliations

  1. College of Optical and Electronic Technology, China Jiliang University, Xueyuan Street No.258, Xiasha Higher Education District, 310018, Hangzhou City, China

    Yan Shi & Longwu Wang

  2. Ningbo Liaoyuan Lighting Co., Ltd, Yuyao, 315408, China

    Yan Shi & Haijun Chen

Authors
  1. Yan Shi
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  2. Longwu Wang
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  3. Haijun Chen
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Correspondence to Yan Shi.

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Shi, Y., Wang, L. & Chen, H. Studies on light extraction design of white LEDs with high luminous efficiency and uniformity. J Opt 44, 136–145 (2015). https://doi.org/10.1007/s12596-015-0239-8

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  • DOI: https://doi.org/10.1007/s12596-015-0239-8

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