SPIE Optics + Photonics最新文献_第10页

Dye-doped thermoplastics for holographic data storage 全息数据存储用染料掺杂热塑性塑料

SPIE Optics + Photonics Pub Date : 2006-09-13 DOI: 10.1117/12.679540

E. Boden, M. Dubois, Xiaolei Shi, B. Lawrence, C. Erben, K. Longley

引用次数: 1

Photopolymers containing triazine monomers for holographic recording 全息记录用含三嗪单体的光聚合物

SPIE Optics + Photonics Pub Date : 2006-09-13 DOI: 10.1117/12.681584

H. Lee, B. Sarwade, Eunkyoung Kim, Sang-Goo Lee

{"title":"Photopolymers containing triazine monomers for holographic recording","authors":"H. Lee, B. Sarwade, Eunkyoung Kim, Sang-Goo Lee","doi":"10.1117/12.681584","DOIUrl":"https://doi.org/10.1117/12.681584","url":null,"abstract":"Photopolymer films containing s-triazine (ST) methacrylic monomers were explored for holographic recording. Photofunctional s-triazine derivative having polymerizable group was synthesized starting from the reaction of a ST di-thiol derivative with methacryloyl chloride to give ST methacrylic monomer substituted with methylthio group (TRSM). ST methacrylic monomer substituted with ethylene oxy unit (TREGM) was synthesized from the reaction of a diamine substituted ST dichloride derivative with hydroxyl-ethyleneoxy methacarylate (HEMA). Photopolymer films prepared by mixing the s-triazine monomer with binder, additives, and photoinitiator were sensitive to a visible light and polymerized upon excitation with a visible laser. The optimization of holographic recording media was achieved by controlling the concentration and chemical structure of monomer composition in photopolymer films to control the diffusion and polymerization of monomer. The new photopolymer films containing ST methacrylic monomer substituted with ethylene oxy unit (TREGM) showed diffraction efficiency reaching ~ 90%. High diffraction efficiency and fast response for the photopolymer prepared from TREGM monomer were ascribed to the effective monomer compatibility with the binder to result in high optical clarity of the film.","PeriodicalId":406438,"journal":{"name":"SPIE Optics + Photonics","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129936350","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Longitudinal sensitivity of the photoinduced molecular migration in azobenzene-containing films 含偶氮苯薄膜中光诱导分子迁移的纵向灵敏度

SPIE Optics + Photonics Pub Date : 2006-09-13 DOI: 10.1117/12.679425

R. Bachelot, A. Bouhelier, G. Wiederrecht, Y. Gilbert, L. Novotný, P. Royer

引用次数: 1

Thermal analysis and design of high-power LED packages and systems 大功率LED封装和系统的热分析和设计

SPIE Optics + Photonics Pub Date : 2006-09-12 DOI: 10.1117/12.687681

L. Kim, M. Shin

引用次数: 15

Optical and structural investigation on InGaN/GaN multiple quantum well light-emitting diodes grown on sapphire by metalorganic chemical vapor deposition 金属有机化学气相沉积法在蓝宝石表面生长InGaN/GaN多量子阱发光二极管的光学和结构研究

SPIE Optics + Photonics Pub Date : 2006-09-12 DOI: 10.1117/12.677653

Zhe Chuan Feng, Jia-Wern Chen, H. Tsai, Jer-Ren Yang, P. Li, Christian Wetzel, T. Detchprohm, J. Nelson, Ian T. Ferguson

{"title":"Optical and structural investigation on InGaN/GaN multiple quantum well light-emitting diodes grown on sapphire by metalorganic chemical vapor deposition","authors":"Zhe Chuan Feng, Jia-Wern Chen, H. Tsai, Jer-Ren Yang, P. Li, Christian Wetzel, T. Detchprohm, J. Nelson, Ian T. Ferguson","doi":"10.1117/12.677653","DOIUrl":"https://doi.org/10.1117/12.677653","url":null,"abstract":"InGaN/GaN multiple quantum well (MQW) light emitting diode (LED) structures with blue and green light emissions have been grown on sapphire substrates by metalorganic chemical vapor deposition. They are investigated by high-resolution X-ray diffraction (HR-XRD), high-resolution transmission electron microscopy (HR-TEM), photoluminescence (PL) and photoluminescence excitation (PLE). HR-XRD showed multiple satellite peaks up to 10th order due to the quantum well superlattice confinement effects. HR-TEM determined the MQW structures and parameters, indicating the high quality of layer interfaces of these LED samples. Excitation power-dependent PL predicates that both piezoelectric field-induced quantum-confined Stark effect and band filling effect influence the luminescent properties. Temperature-dependent PL shows that the QW PL emission peak exhibits a monotonic red-shift and that the full width at half maximum of the PL band shows a W-shaped temperature-dependent behavior with increasing temperature. From the PLE results, a large energy difference, so-called quantum confined Stokes shift, between the band-edge absorption and emission was observed. Penetrating TEM revealed the V-shape defects, and quantum dot-like structures within the InGaN well region, which leads to intense light emissions from these MQW LEDs.","PeriodicalId":406438,"journal":{"name":"SPIE Optics + Photonics","volume":"101 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122971157","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Multiple light recycling with the Carambola 杨桃多重光循环

SPIE Optics + Photonics Pub Date : 2006-09-12 DOI: 10.1117/12.679580

L. Fu, R. Leutz, H. Ries

引用次数: 0

Color temperature tunable white light LED system 色温可调的白光LED系统

SPIE Optics + Photonics Pub Date : 2006-09-12 DOI: 10.1117/12.679688

I. Speier, M. Salsbury

引用次数: 58

White photoluminescence from SiNx films prepared by plasma enhanced chemical vapor deposition 等离子体增强化学气相沉积法制备的SiNx薄膜的白色光致发光

SPIE Optics + Photonics Pub Date : 2006-09-12 DOI: 10.1117/12.685281

Z. Kang, B. Wagner, J. Parrish, C. Summers

{"title":"White photoluminescence from SiNx films prepared by plasma enhanced chemical vapor deposition","authors":"Z. Kang, B. Wagner, J. Parrish, C. Summers","doi":"10.1117/12.685281","DOIUrl":"https://doi.org/10.1117/12.685281","url":null,"abstract":"Intense visible blue to red emissions were obtained from SiNx thin films prepared by plasma enhanced chemical vapor deposition (PECVD) using SiH4 and NH3 as the source gases. A continuous blue shift of the photoluminescence (PL) peak from 660nm to 440nm was observed by increasing the NH3 flow rate from 20 to 150sccm, while the flow rate of N2 diluted 2% SiH4 was fixed at 650sccm. This controllable PL was attributed to the quantum confinement effect of Si quantum dots (QDs) which were formed during the deposition process and embedded in the SiNx films. White photoluminescence with multiple emission peaks was achieved for potential solid state lighting applications from multi-layered SiNx films by changing the SiH4/NH3 ratio during the deposition process. This was attributed to a combination of Si quantum dots with different sizes within the different layers. Surface texturing of the thin film samples was conducted by potassium hydroxide (0.56%) etching the (100) Si substrate for 3~40 min at 80°C before deposition. The reflectivity of the etched samples decreased with increasing etch time due to increased surface roughness. The extraction efficiency of light emission from the textured SiNx thin films was significantly improved, owing to a depression of the internal reflection and interference effects. In addition, the elimination of the multiple emission peaks by surface texturing significantly affected the color coordinates of the output spectrum.","PeriodicalId":406438,"journal":{"name":"SPIE Optics + Photonics","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132588196","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Stability and performance evaluation of high-brightness light-emitting diodes under DC and pulsed bias conditions 高亮度发光二极管在直流和脉冲偏置条件下的稳定性和性能评价

SPIE Optics + Photonics Pub Date : 2006-09-12 DOI: 10.1117/12.683803

M. Meneghini, L. Trevisanello, S. Podda, S. Buso, G. Spiazzi, G. Meneghesso, E. Zanoni

{"title":"Stability and performance evaluation of high-brightness light-emitting diodes under DC and pulsed bias conditions","authors":"M. Meneghini, L. Trevisanello, S. Podda, S. Buso, G. Spiazzi, G. Meneghesso, E. Zanoni","doi":"10.1117/12.683803","DOIUrl":"https://doi.org/10.1117/12.683803","url":null,"abstract":"This paper presents an experimental analysis of high brightness light emitting diodes (HBLEDs) performance and stability under dc and pulsed current bias. Three different families of HBLEDs from three leading manufacturers have been considered. The analysis was carried out by means of current-voltage, integrated optical power and electroluminescence measurements, and failure analysis. After an initial characterization of the electrical, optical and thermal behavior of the devices, a set of ageing tests was carried out, both under dc and pulsed bias conditions. Identified degradation modes were efficiency decrease, series resistance increase, leakage current increase, and modifications of the emitted spectrum. Characterization of devices behavior during stress indicated (i) generation of non-radiative components, (ii) degradation of the anode contacts and bonding wires, (iii) degradation of the phosphorous layer conversion efficiency and (iv) of the plastic package as possible responsible of the electrical and optical degradation of the LEDs. Comparison between dc and pulsed stress carried out using the same average current level and different duty cycle values showed that the use of pulsed bias can reduce the degradation rate with respect to dc bias. However, for duty cycles lower than 20%, fast degradation and abrupt ruptures can take place, due to the high peak current levels.","PeriodicalId":406438,"journal":{"name":"SPIE Optics + Photonics","volume":"88 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131931307","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 28

Geodesic lenses applied to nonimaging optics 用于非成像光学的测地线透镜

SPIE Optics + Photonics Pub Date : 2006-09-11 DOI: 10.1117/12.682128

J. Miñano, P. Benítez, Bill Parkyn, D. Grabovičkić, Fernando García, J. Blen, A. Santamaria, J. Chaves, W. Falicoff

{"title":"Geodesic lenses applied to nonimaging optics","authors":"J. Miñano, P. Benítez, Bill Parkyn, D. Grabovičkić, Fernando García, J. Blen, A. Santamaria, J. Chaves, W. Falicoff","doi":"10.1117/12.682128","DOIUrl":"https://doi.org/10.1117/12.682128","url":null,"abstract":"A novel waveguide-optical integrator is introduced for applications to LEDs. The concept is based upon a Kohler illuminator made of Luneburg lenses. Typical Kohler illuminators are formed by pairs of thin lenses, and perform badly when the paraxial approximation is rough, i.e., when the angular span of the incoming rays is wide. In contrast, the new illuminator performs ideally for angular spans up to 90o (±45o), and has only a 3% loss for a 180o angular span. In general such an illuminator cannot be made in 3D, because adjacent Luneburg lenses overlap. It can, however, be implemented in planar optics, by using Rinehart geodesic lenses, which moreover do not use gradient index material. This waveguide device has application in illumination engineering as a light mixer, particularly for LEDs. Another light mixer using a combination of two kaleidoscopes with a geodesic lens is also presented. Irradiance at the exit of a kaleidoscope has good light mixing if the kaleidoscope is long enough, but the intensity is never well mixed, irrespective of the length. Inserting a Rinehart geodesic lens produces a 90-degree phase-space rotation of the rays, i.e., it exchanges irradiance and intensity. A further kaleidoscope assures complete mixing in both irradiance and intensity.","PeriodicalId":406438,"journal":{"name":"SPIE Optics + Photonics","volume":"58 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122573390","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0