Reflective optics with wide field of view has been applied more and more widely in EUVL or space optics, and also plays an important role in promoting scientific and technological research. Among the reflective optics...Reflective optics with wide field of view has been applied more and more widely in EUVL or space optics, and also plays an important role in promoting scientific and technological research. Among the reflective optics, the off-axis reflective optics is the most hopeful solution to the ever-highest demands of these applications. This paper gives the requirements of both the above mentioned applications and the similarities and differences between these two kinds of optical systems. Finally, a design example of off-axis reflective optics with wide field of view is presented and described.展开更多
Mini LED背光显示产品使用光学扩散板和复合膜进行亮度提升和均匀性提升,光学膜将大幅改变背光的色坐标和亮度参数。本文测试结果表明,复合膜亮度增益在1.5~2倍,亮度增益排序为POP>DPP>MOP>DOP。经分析这是由于不同复合膜对光...Mini LED背光显示产品使用光学扩散板和复合膜进行亮度提升和均匀性提升,光学膜将大幅改变背光的色坐标和亮度参数。本文测试结果表明,复合膜亮度增益在1.5~2倍,亮度增益排序为POP>DPP>MOP>DOP。经分析这是由于不同复合膜对光束立体角的矫正作用引起,即光学微结构对杂散光收集能量大于扩散剂散射产生的能量耗损。同时复合膜大幅提高了背光色坐标,其中扩散板+DPP色坐标变化Δx为0.01,Δy为0.0187,这是由于扩散粒子的Mie散射使短波段蓝光的光辐射能大幅耗损。对于量子点显示,从多层光学微结构反射回量子膜的蓝光将产生多重光致激发现象,使复合膜对xy色坐标值的增幅进一步加大。光学复合膜产生的亮度增益和色温降低有利于显示产品在出厂时将色温调到低色温从而保证显示亮度。展开更多
为了快速准确地计算电大尺寸目标高频散射场,降低计算代价,本文提出了一种基于八叉树多层结构与二次曲面离散技术的多层快速物理光学(multilevel fast physical optics,MLFPO)算法。八叉树多层结构的引入能够充分利用并行技术对计算加速...为了快速准确地计算电大尺寸目标高频散射场,降低计算代价,本文提出了一种基于八叉树多层结构与二次曲面离散技术的多层快速物理光学(multilevel fast physical optics,MLFPO)算法。八叉树多层结构的引入能够充分利用并行技术对计算加速;二次曲面离散技术可以更好地拟合凸散射体的表面,相较于平面三角形面片能有效降低未知量数目。在此基础上,本文将MLFPO算法应用目标拓展到复杂的多层涂覆目标。数值算例表明,与商业软件FEKO中的PO算法相比,MLFPO算法在S、C、X、Ku四个波段的双站散射场误差在1.54 dB以内,且计算速度随着频率增加可以提升8倍以上,而计算存储度降低98%。说明MLFPO算法在确保物理光学散射场计算精度的同时能够降低计算代价,是分析电大尺寸目标高频电磁散射问题的有效方法。展开更多
Phase measuring deflectometry(PMD)is a robust,noncoherent technique for the characterization of specular surface.For measuring high specular reflectivity surface,PMD can deliver micron radian range local gradient.Howe...Phase measuring deflectometry(PMD)is a robust,noncoherent technique for the characterization of specular surface.For measuring high specular reflectivity surface,PMD can deliver micron radian range local gradient.However,when the measured surface has low specular reflectivity,the accuracy of the measured gradient is low since the captured fringe pattern shows low signal to noise ratio.The phase error characteristics in PMD system when testing low reflectivity surfaces are analyzed.The analysis illustrates that the random phase error increases rapidly while the nonlinear error drops slowly with the decreasing of the tested surface reflectivity.In order to attain high precision measurement of low reflectivity specular surface,a robust error reduction method based on wavelet de-noising is proposed to reduce the phase error.This error reduction method is compared with several other normally used methods in both simulation and experiment work.The method based on the wavelet de-noising shows better performance when measuring the low reflectivity specular surface.展开更多
文摘Reflective optics with wide field of view has been applied more and more widely in EUVL or space optics, and also plays an important role in promoting scientific and technological research. Among the reflective optics, the off-axis reflective optics is the most hopeful solution to the ever-highest demands of these applications. This paper gives the requirements of both the above mentioned applications and the similarities and differences between these two kinds of optical systems. Finally, a design example of off-axis reflective optics with wide field of view is presented and described.
文摘为了快速准确地计算电大尺寸目标高频散射场,降低计算代价,本文提出了一种基于八叉树多层结构与二次曲面离散技术的多层快速物理光学(multilevel fast physical optics,MLFPO)算法。八叉树多层结构的引入能够充分利用并行技术对计算加速;二次曲面离散技术可以更好地拟合凸散射体的表面,相较于平面三角形面片能有效降低未知量数目。在此基础上,本文将MLFPO算法应用目标拓展到复杂的多层涂覆目标。数值算例表明,与商业软件FEKO中的PO算法相比,MLFPO算法在S、C、X、Ku四个波段的双站散射场误差在1.54 dB以内,且计算速度随着频率增加可以提升8倍以上,而计算存储度降低98%。说明MLFPO算法在确保物理光学散射场计算精度的同时能够降低计算代价,是分析电大尺寸目标高频电磁散射问题的有效方法。
基金support by the National Nature Science Foundation of China (61421002, 61327004)
文摘Phase measuring deflectometry(PMD)is a robust,noncoherent technique for the characterization of specular surface.For measuring high specular reflectivity surface,PMD can deliver micron radian range local gradient.However,when the measured surface has low specular reflectivity,the accuracy of the measured gradient is low since the captured fringe pattern shows low signal to noise ratio.The phase error characteristics in PMD system when testing low reflectivity surfaces are analyzed.The analysis illustrates that the random phase error increases rapidly while the nonlinear error drops slowly with the decreasing of the tested surface reflectivity.In order to attain high precision measurement of low reflectivity specular surface,a robust error reduction method based on wavelet de-noising is proposed to reduce the phase error.This error reduction method is compared with several other normally used methods in both simulation and experiment work.The method based on the wavelet de-noising shows better performance when measuring the low reflectivity specular surface.
