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浏览/检索结果: 共3条，第1-3条 帮助 限定条件 专题：长春光学精密机械与物理研究所    第一署名单位    第一作者单位    通讯作者单位     已选(0)清除 条数/页：5101520253035404550556065707580859095100   排序方式：请选择作者升序作者降序题名升序题名降序发表日期升序发表日期降序提交时间升序提交时间降序 Design of compound Fresnel-R lenses for new high-efficient photovoltaic concentrator (EI CONFERENCE) 会议论文 Nonimaging Optics: Efficient Design for Illumination and Solar Concentration VII, August 1, 2010 - August 4, 2010, San Diego, CA, United states Jing L.; Liu H.; Lu Z.; Zhao H. 收藏  |  浏览/下载：24/0  |  提交时间：2013/03/25 A new design of compound Fresnel-R concentrator is presented which is composed of two lenses: a primary lens (Fresnel lens) that works by total internal reflection at outer facets but refraction at inner facets  and a secondary lens that works by refraction. In contrast to previous Fresnel lens concentrator  this design increases the acceptance angle  improves the irradiance uniformity on the solar cell  and reduces the aspect ratio significantly. Another outstanding advantage of this concentrator is the fact that it mainly works by performing total internal reflection  reducing chromatic dependence as well as Fresnel losses. An optical efficiency more than 80% can be achieved. Moreover  in order to reduce the influence of manufacture accuracy and to increase the optical efficiency further  the central part of the bottom of the secondary lens which directly adhered to the solar cell is designed as a cone-shaped prism to collect the sunlight that doesn't reach the solar cell. 2010 SPIE.   Optimization procedure for design of heliostat field layout of a 1MWe solar tower thermal power plant (EI CONFERENCE) 会议论文 Solid State Lighting and Solar Energy Technologies, November 12, 2007 - November 14, 2007, Beijing, China Wei X.; Lu Z.; Lin Z.; Zhang H.; Ni Z. 收藏  |  浏览/下载：19/0  |  提交时间：2013/03/25 A procedure for designing and optimizing heliostat field layout of solar tower thermal power plant is developed. The ray tracing is used for the calculation of the optical efficiency of field. The mathematical theory of the calculation is derived. The parametric search algorithm  which allows variation of the field parameters within a specified range  is used for the optimization of field. The field layout is made automatically according to the no-blocking loss condition and the heliostats are located at the positions where the annual incident cosine value is higher. In this way  the blocking and cosine losses are lowered. Because the optimization of the distance between fore-and-aft two rows of heliostat is avoided  the computer time is reduced effectively. Using this procedure the heliostat field of a 1MWe solar tower power plant was designed. Four modes of layout including North-South cornfield  North-South stagger  Radial cornfield and Radial stagger were experimented and optimized respectively. The comparison of the field efficiency for the four optimized results was made. It is concluded that the North-South cornfield layout is the optimal decision for the 1MWe solar tower power plant.   Study on optical parts of MOEMS optical switch with low insertion loss (EI CONFERENCE) 会议论文 MEMS/MOEMS Technologies and Applications II, November 10, 2004 - November 12, 2004, Beijing, China Ming A.; Liang J.; Lan W.; Dong W.; Yao J.; Wang W.; Le Z.; Chen W.; Wang L. 收藏  |  浏览/下载：22/0  |  提交时间：2013/03/25 We study insertion losses of optical switch when the laser beam is propagating during the free space between two single mode fibers (SMFs) and the related assemblage challenges  Then a new packaging structure is developed for the hybrid-integration of free-space MOEMS (micro-opto-electro-mechanical systems) chip with a silicon micromachined submount to improve alignment accuracy. The submount is designed to accommodate various free-space MOEMS chips with minimal active optical alignment  thus reducing the packaging cost. The silicon submount has a central recess to place the MOEMS chip in  sixteen V-grooves for optical fibers  and micropits for micro ball lenses  all bulk micromachined at the same time by a single anisotropic wet etching step. A corner compensation technique is employed to prevent erosion of the convex corners  where different geometries meet. Through this assembling method  the fiber  micro ball lens can be aligned preciously thus reduced lateral and angular misalignment between them. Then total insertion losses can be decreased.