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991.
为了满足常温Yb:YAG激光放大器对泵浦功率密度的要求,设计了一种高缩束比的耦合系统。根据激光二极管(LD)的发光特性,将输出功率为80 kW的LD阵列进行拟球面排列,采用正交柱面透镜配合空心导光管进行泵浦耦合,耦合系统的面积缩束比高达86∶1。模拟计算表明,该耦合系统的耦合效率对导光管反射板的反射率依赖性较低,且脱离耦合系统后的泵浦光传输8.5 mm后,依然可以保持泵浦光场的轮廓,满足端面泵浦的常温Yb:YAG片状放大器对泵浦耦合系统的要求。 相似文献
992.
推导出了离焦量与聚焦误差信号功率的关系式。利用MATLAB软件仿真,详细分析了像散透镜系统各个参数对离焦量、灵敏度、光斑大小等的影响,得到了像散圆透镜与像散柱透镜焦距之间的距离关系。结果发现聚焦物镜和探测器参数对最小离焦量、灵敏度、精度有决定性的影响。提出了像散透镜系统各光学参数选择的原则和方法,并以德国Silicon Sensor公司的QP50-6型四象限探测器为例,详细分析了离焦量与聚焦误差信号功率的线性关系。这些工作对建立满足应用对象要求的像散法离焦检测系统具有重要的指导意义。 相似文献
993.
介绍了将菲涅尔透镜前置于太阳能电池板适当位置以提高转换效率的实验研究。通过测试单晶硅、多晶硅电池单元加聚焦透镜前、后,以及改变不同入射角度照射单晶硅、多晶硅电池单元对输出伏安特性的影响,得出增加透镜聚光可以有效提升太阳能的转换效率,同时需要保证光源垂直入射。 相似文献
994.
995.
At present, regarding to the machining of aspheric lens mold, there are two major methods to carry out the on-machine measurement (OMM) — contacting method (CM) and non-contacting method (NCM). Here such two methods are reviewed in detail. CM is mainly based on the contacting probe which is scratching aspheric surface of lens mold to achieve profile data. To be efficient, an idea with 45° tilt of probe is proposed for OMM of lens mold by Suzuki. But generally speaking, the contacting OMM is not so efficient and can only deal with axisymmetric aspheric lens mold. On the contrary, NCM mostly uses laser to achieve aspheric profile without any contact. On ultra-precision lathe, laser scanning system or laser interferometer is mounted on the frame of lathe and transfers measurement data to machining system efficiently. However, most NCMs need stable environment and low working noise except instantaneous phase-shifting shearing interferometry (IPSSI). Therefore, a new idea about IPSSI is proposed in this paper to realize OMM of lens molds. Unfortunately, it's also difficult to test the high numerical aperture aspheric or free-form lens molds. By comparison, the newly-developed fringe reflection (FR) method is becoming the promising method because it features the high efficiency and high accuracy. However, this method has not been used for OMM system yet. Much research should be conducted for FR OMM technology. 相似文献
996.
In this article, a differential equation, which describes the shape of the liquid interface in a cylindrical chamber when the density difference of two liquids is zero, is provided. And an analytical solution is found for the differential equation which indicates the interface shape is spherical. And such a result is not independent on the vessel size. In experiment, by means of measuring the focal lengths of liquid lenses with different vessel size, the results show that the focal lengths ratio is quite approximate to the inner radius ratio of the cylindrical chamber, which can inversely verifies that the interface shape of liquid lens with two same density liquids is spherical. 相似文献
997.
998.
Mladen Franko 《应用光谱学评论》2013,48(4):358-388
Abstract Recent applications of thermal lens spectrometry in liquid chromatography (HPLC, ion chromatography), capillary electrophoresis, and flow injection analysis are reviewed. Possible effects of performing TLS measurements in flows are discussed initially for different TLS configurations. The emphasis is given to the analysis of real samples, and the performances of various detection schemes in combination with chromatographic techniques and FIA are discussed particularly in terms of sensitivity, sample throughput, and eventual interferences from complex matrices. Coaxial TLS detection with continuous wave excitation is most suitable for detection in HPLC, ion chromatography, and FIA using long‐path length cells, when large volume samples are available. On the other hand, transverse or crossed beam TLS was found most suitable for detection in CE where it provides low absolute LODs, which are lowered even further by thermal lens microscopy on microchips, where the capability of detecting a single molecule in the detection volume was demonstrated. 相似文献
999.
1000.