Angular color uniformity(ACU)is a key factor used to evaluate the light quality of white-light emitting diodes(LEDs).In this study,a novel double remote micro-patterned phosphor film(double RMPP film)was used to enhan...Angular color uniformity(ACU)is a key factor used to evaluate the light quality of white-light emitting diodes(LEDs).In this study,a novel double remote micro-patterned phosphor film(double RMPP film)was used to enhance the ACU of a remote phosphor(RP)down-light lamp.A conventional RP film and remote phosphor film with single micro-patterned film(single RMPP film)also were examined for comparison.The angular correlated color temperature(CCT)distributions and the optical performance of the films were experimentally measured.The measurement results showed that double RMPP film configuration exhibited better color uniformity with a CCT deviation of only 441 K,compared with 556 K for the single RMPP film configuration and 1390 K for the RP film configuration.A simulation based on FDTD and ray tracing combined method also confirmed the ACU improvement.In addition,compared with the conventional RP film,the luminous efficiency of single and double RMPP film configurations was increased by 6.68% and 4.69%,respectively,at a driving current of 350 mA.The enhancement of the ACU and luminous efficiency are due to the scattering and mixing effect of the micropatterned film.Moreover,the double RMPP film configuration had better CCT stability at different currents than the other two configurations.The results demonstrated the effectiveness and superiority of double RMPP film in white LED applications.展开更多
Composite ceramic phosphor(CCP)is a candidate light-conversion material to obtain the high-quality laser lighting source.Phosphors based on the transmissive configuration model could not simultaneously meet the requir...Composite ceramic phosphor(CCP)is a candidate light-conversion material to obtain the high-quality laser lighting source.Phosphors based on the transmissive configuration model could not simultaneously meet the requirements of angular color uniformity and high thermal stability.In this study,a novel composite structure ceramic was designed,including Al_(2)O_(3)-YAG:Ce/YAG layered ceramic with a size of 1 mm×1 mm for lighting,and Al_(2)O_(3) ceramic(φ=16.0 mm)was used as the wrapping material due to its outstanding thermal stability.The prepared ceramics exhibited excellent thermal performance and no yellow ring phenomenon.Through this design,we achieved the match of the intensity distribution of the blue and yellow lights,resulting in a high angular color uniformity of 0.9 with a view angle of±80°.All ceramics showed no luminous saturation phenomenon,even the laser power density was increased up to 47.51 W/mm^(2).A high-brightness white-light source with a luminous flux of 618 lm,a luminous efficiency of 126 lm/W,a CCT of 6615 K,and a CRI of 69.9 was obtained in the transmissive configuration.In particular,the surface temperature of the ceramic was as low as 74.1℃ under a high laser radiation(47.51 W/mm^(2)).These results indicate that Al_(2)O_(3)/Al_(2)O_(3)-YAG:Ce/YAG composite structure ceramic is a promising luminescent material in the high-power laser lighting applications.展开更多
基金National Natural Science Foundation of China(NSFC)(U1401249,51405161)Guandong Natural Science Foundation(2014A030312017)+1 种基金China Postdoctoral Science Foundation(2015T80904)Science&Technology Program of Guangdong Province(2014B010121002)
文摘Angular color uniformity(ACU)is a key factor used to evaluate the light quality of white-light emitting diodes(LEDs).In this study,a novel double remote micro-patterned phosphor film(double RMPP film)was used to enhance the ACU of a remote phosphor(RP)down-light lamp.A conventional RP film and remote phosphor film with single micro-patterned film(single RMPP film)also were examined for comparison.The angular correlated color temperature(CCT)distributions and the optical performance of the films were experimentally measured.The measurement results showed that double RMPP film configuration exhibited better color uniformity with a CCT deviation of only 441 K,compared with 556 K for the single RMPP film configuration and 1390 K for the RP film configuration.A simulation based on FDTD and ray tracing combined method also confirmed the ACU improvement.In addition,compared with the conventional RP film,the luminous efficiency of single and double RMPP film configurations was increased by 6.68% and 4.69%,respectively,at a driving current of 350 mA.The enhancement of the ACU and luminous efficiency are due to the scattering and mixing effect of the micropatterned film.Moreover,the double RMPP film configuration had better CCT stability at different currents than the other two configurations.The results demonstrated the effectiveness and superiority of double RMPP film in white LED applications.
基金the National Key R&D Program of China(2021YFB3501700,2023YFB3506600)National Natural Science Foundation of China(52202135,61975070,and 52302141)+5 种基金Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD),International S&T Cooperation Program of Jiangsu Province(BZ2023007)Key Research and Development Project of Jiangsu Province(BE2023050,BE2021040)Natural Science foundation of Jiangsu Province(BK20221226)Graduate Research and Innovation Projects of Jiangsu Province(KYCX22_2845)Special Project for Technology Innovation of Xuzhou City(KC23380,KC21379,KC22461,and KC22497)Open Project of State Key Laboratory of Crystal Materials(KF2205).
文摘Composite ceramic phosphor(CCP)is a candidate light-conversion material to obtain the high-quality laser lighting source.Phosphors based on the transmissive configuration model could not simultaneously meet the requirements of angular color uniformity and high thermal stability.In this study,a novel composite structure ceramic was designed,including Al_(2)O_(3)-YAG:Ce/YAG layered ceramic with a size of 1 mm×1 mm for lighting,and Al_(2)O_(3) ceramic(φ=16.0 mm)was used as the wrapping material due to its outstanding thermal stability.The prepared ceramics exhibited excellent thermal performance and no yellow ring phenomenon.Through this design,we achieved the match of the intensity distribution of the blue and yellow lights,resulting in a high angular color uniformity of 0.9 with a view angle of±80°.All ceramics showed no luminous saturation phenomenon,even the laser power density was increased up to 47.51 W/mm^(2).A high-brightness white-light source with a luminous flux of 618 lm,a luminous efficiency of 126 lm/W,a CCT of 6615 K,and a CRI of 69.9 was obtained in the transmissive configuration.In particular,the surface temperature of the ceramic was as low as 74.1℃ under a high laser radiation(47.51 W/mm^(2)).These results indicate that Al_(2)O_(3)/Al_(2)O_(3)-YAG:Ce/YAG composite structure ceramic is a promising luminescent material in the high-power laser lighting applications.
