Heat dissipation is an important part of light-emitting diode(LED)filament research and has aroused constant concern.In this paper,we studied the thermal performance of flexible LED filament by numerical simulation an...Heat dissipation is an important part of light-emitting diode(LED)filament research and has aroused constant concern.In this paper,we studied the thermal performance of flexible LED filament by numerical simulation and through experiment.The heat dissipation characteristics of spring-like structure flexible LED filament were computed by finite volume method,and it was found that the chip junction temperature was closely related to the pitch and the bending radius.The effect of inclination angle of lighting LED filament was discussed because it is relevant to the spring-like structure flexible LED filament in geometry.The results demonstrated that the temperature of the filament increases as the inclination angle improves.展开更多
We demonstrated a diode-pumped vertical external cavity surface emitting laser with simple plane-concave cavity. When the pump power at a wavelength of 811.6 nm is 1.5 W, the maximum output power is 40.4 mW at the wav...We demonstrated a diode-pumped vertical external cavity surface emitting laser with simple plane-concave cavity. When the pump power at a wavelength of 811.6 nm is 1.5 W, the maximum output power is 40.4 mW at the wavelength of 1005.8 nm. The optical-optical conversion efficiency is 2.7%. .展开更多
In the process of producing a white light emitting diode, the consistency of the optical coherence and stability of the photochromic properties is a crucial index for measuring the quality of the product. Phosphor sed...In the process of producing a white light emitting diode, the consistency of the optical coherence and stability of the photochromic properties is a crucial index for measuring the quality of the product. Phosphor sedimentation is a significant factor affecting optical coherence, thus, in this paper, seven sets of control experiments were set up with the phenomenon of the phosphor precipitation at time intervals 0, 2, 5, 10, 20, 30, and 40 min.The color coordination concentration and optical properties were also tested. The results indicate that phosphor sedimentation occurs between 0 and 20 min, during which the color coordinate placement is concentrated, the central coordinates are(x = 0.4432 ± 0.004, y = 0.4052±0.002); the quality was verified because the supply demand chain management(SDCM) was no greater than 7. Later, between 30 and 40 min, the central coordinates are(x = 0.4366 ± 0.003, y = 0.4012 ± 0.003), which had an SDCM value higher than 7, and had a more discrete color placement; it does not meet the requirements of the national standard GBT24823-2016 general lighting LED module performance.展开更多
In the realm of advanced electrochemical energy storage,the study of diverse electrolyte salts as integral components of electrolyte engineering has garnered immense attention.Notably,lithium di(fluoro)oxalateborate(L...In the realm of advanced electrochemical energy storage,the study of diverse electrolyte salts as integral components of electrolyte engineering has garnered immense attention.Notably,lithium di(fluoro)oxalateborate(Li DFOB)as the representative DFOB-contained electrolyte salts,which possesses structural attributes resembling both lithium bis(oxalate)borate(LiBOB)and lithium tetrafluoroborate(LiBF4),has garnered significant attention initially as a classical additive for the formation of solid electrolyte interface(SEI)films in graphite anodes.However,its unique properties have also piqued interest in other battery components,encompassing current collectors,capacity-enhanced cathodes or anodes,polymer solid-state electrolytes,and the full batteries.The introduction of Li DFOB or NaDFOB into these batteries exhibits a dual-faceted effect,with the beneficial aspect outweighing the potential drawbacks.Herein,we present a comprehensive overview of the research advancements surrounding LiDFOB,including the synthesis techniques of Li DFOB,the inherent properties of Li DFOB and LiDFOB-based electrolyte solutions,and the impact of LiDFOB on the performance of traditional graphite anodes,capacity-enlarged anodes,various classic cathodes,and the full batteries.And sectional content is about the usage of Na DFOB in Na-ion batteries.This review aims to aid readers in understanding the pivotal role of LiDFOB and NaDFOB as a constituent of electrolytes and how its utilization can influence electrode materials and other components,ultimately altering the electrochemical energy storage device's performance.展开更多
Compound eyes(CEs)that feature ultra-compact structures and extraordinary versatility have revealed great potential for cutting-edge applications.However,the optoelectronic integration of CEs with available photodetec...Compound eyes(CEs)that feature ultra-compact structures and extraordinary versatility have revealed great potential for cutting-edge applications.However,the optoelectronic integration of CEs with available photodetectors is still challenging because the planar charge-coupled device(CCD)/complementary metal oxide semiconductor(CMOS)detector cannot match the spatially distributed images formed by CE ommatidia.To reach this end,we report here the optoelectronic integration of CEs by manufacturing 3D nonuniform ommatidia for developing an ultra-compact on-chip camera.As a proof-of-concept,we fabricated microscale CEs with uniform and nonuniform ommatidia through femtosecond laser two-photon photopolymerization,and compared their focusing/imaging performance both theoretically and experimentally.By engineering the surface profiles of the ommatidia at different positions of the CE,the images formed by all the ommatidia can be tuned on a plane.In this way,the nonuniform CE can be directly integrated with a commercial CMOS photodetector,forming an ultra-compact CE camera.Additionally,we further combine the CE camera with a microfluidic chip,which can further serve as an on-chip microscopic monitoring system.We anticipate that such an ultra-compact CE camera may find broad applications in microfluidics,robotics,and micro-optics.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant No.51302171)Science and Technology Commission of Shanghai Municipality,China(Grant No.14500503300)+2 种基金Shanghai Municipal Alliance Program,China(Grant No.Lm201547)Shanghai Cooperative Project,China(Grant No.ShanghaiCXY-2013-61)Jiashan County Technology Program,China(Grant No.20141316)
文摘Heat dissipation is an important part of light-emitting diode(LED)filament research and has aroused constant concern.In this paper,we studied the thermal performance of flexible LED filament by numerical simulation and through experiment.The heat dissipation characteristics of spring-like structure flexible LED filament were computed by finite volume method,and it was found that the chip junction temperature was closely related to the pitch and the bending radius.The effect of inclination angle of lighting LED filament was discussed because it is relevant to the spring-like structure flexible LED filament in geometry.The results demonstrated that the temperature of the filament increases as the inclination angle improves.
基金The authors thank I. Sagnes and D. Romanini for the supply of the VECSEL chip. X. Guo's e-mail address is guoxp1105@yahoo.com.cn.
文摘We demonstrated a diode-pumped vertical external cavity surface emitting laser with simple plane-concave cavity. When the pump power at a wavelength of 811.6 nm is 1.5 W, the maximum output power is 40.4 mW at the wavelength of 1005.8 nm. The optical-optical conversion efficiency is 2.7%. .
基金Project supported by the National Natural Science Foundation of China(No.11474036)the Natural Science Foundation of Shanghai(No.12ZR1430900)+4 种基金the Shanghai Institute of Technology Talents Scheme(No.YJ2014-04)the Shanghai Municipal Alliance Program(Nos.Lm201514,Lm201505,Lm201455)the Science and Technology Commission of Shanghai Municipality(CN)(No.14500503300)Shanghai Cooperative Project(No.Shanghai CXY-2013-61)Jiashan County Technology Program(No.20141316)
文摘In the process of producing a white light emitting diode, the consistency of the optical coherence and stability of the photochromic properties is a crucial index for measuring the quality of the product. Phosphor sedimentation is a significant factor affecting optical coherence, thus, in this paper, seven sets of control experiments were set up with the phenomenon of the phosphor precipitation at time intervals 0, 2, 5, 10, 20, 30, and 40 min.The color coordination concentration and optical properties were also tested. The results indicate that phosphor sedimentation occurs between 0 and 20 min, during which the color coordinate placement is concentrated, the central coordinates are(x = 0.4432 ± 0.004, y = 0.4052±0.002); the quality was verified because the supply demand chain management(SDCM) was no greater than 7. Later, between 30 and 40 min, the central coordinates are(x = 0.4366 ± 0.003, y = 0.4012 ± 0.003), which had an SDCM value higher than 7, and had a more discrete color placement; it does not meet the requirements of the national standard GBT24823-2016 general lighting LED module performance.
基金financially supported by Talent start-up funds of DGUT(No.221110217)。
文摘In the realm of advanced electrochemical energy storage,the study of diverse electrolyte salts as integral components of electrolyte engineering has garnered immense attention.Notably,lithium di(fluoro)oxalateborate(Li DFOB)as the representative DFOB-contained electrolyte salts,which possesses structural attributes resembling both lithium bis(oxalate)borate(LiBOB)and lithium tetrafluoroborate(LiBF4),has garnered significant attention initially as a classical additive for the formation of solid electrolyte interface(SEI)films in graphite anodes.However,its unique properties have also piqued interest in other battery components,encompassing current collectors,capacity-enhanced cathodes or anodes,polymer solid-state electrolytes,and the full batteries.The introduction of Li DFOB or NaDFOB into these batteries exhibits a dual-faceted effect,with the beneficial aspect outweighing the potential drawbacks.Herein,we present a comprehensive overview of the research advancements surrounding LiDFOB,including the synthesis techniques of Li DFOB,the inherent properties of Li DFOB and LiDFOB-based electrolyte solutions,and the impact of LiDFOB on the performance of traditional graphite anodes,capacity-enlarged anodes,various classic cathodes,and the full batteries.And sectional content is about the usage of Na DFOB in Na-ion batteries.This review aims to aid readers in understanding the pivotal role of LiDFOB and NaDFOB as a constituent of electrolytes and how its utilization can influence electrode materials and other components,ultimately altering the electrochemical energy storage device's performance.
基金financial supports from Natural Science Foundation of China(Grant No.61935008,T2325014,62205174 and 62275100)。
文摘Compound eyes(CEs)that feature ultra-compact structures and extraordinary versatility have revealed great potential for cutting-edge applications.However,the optoelectronic integration of CEs with available photodetectors is still challenging because the planar charge-coupled device(CCD)/complementary metal oxide semiconductor(CMOS)detector cannot match the spatially distributed images formed by CE ommatidia.To reach this end,we report here the optoelectronic integration of CEs by manufacturing 3D nonuniform ommatidia for developing an ultra-compact on-chip camera.As a proof-of-concept,we fabricated microscale CEs with uniform and nonuniform ommatidia through femtosecond laser two-photon photopolymerization,and compared their focusing/imaging performance both theoretically and experimentally.By engineering the surface profiles of the ommatidia at different positions of the CE,the images formed by all the ommatidia can be tuned on a plane.In this way,the nonuniform CE can be directly integrated with a commercial CMOS photodetector,forming an ultra-compact CE camera.Additionally,we further combine the CE camera with a microfluidic chip,which can further serve as an on-chip microscopic monitoring system.We anticipate that such an ultra-compact CE camera may find broad applications in microfluidics,robotics,and micro-optics.
