1 滨州学院飞行学院，山东 滨州 256600
2 北京空间机电研究所，北京 100094
3 大连工业大学信息科学与工程学院，辽宁 大连 116034
系统地探究了典型多光谱彩色成像系统的最优光谱通道数的确定问题。在前期多目标滤色片优化选取方法的基础上，将仅限于相同通道滤色器优化的概念拓展至不同通道数最优滤色器的优化，从而达到最优通道数确定的目的。基于Munsell光谱反射率数据集构建光谱反射率成像目标，通过真实CCD成像传感器的光谱灵敏度、D65光源的光谱功率分布以及高斯滤色器模型和最大线性独立滤色器选择算法，在10个噪声水平下实现了3~31个光谱通道，即29个虚拟多光谱相机对成像目标的光谱反射率重建的仿真计算。结果表明，通道数小于8时，5通道滤色器表现最优；和A光源相比，D65光源下的5通道最优滤色器的最大带宽达到80 nm，性能有显著的提升。
色度学 成像系统 计算方法 光谱通道数 多光谱彩色成像
Author Affiliations
Abstract
1 Beijing Engineering Research Center of Mixed Reality and Advanced Display, School of Optics and Photonics, Beijing Institute of Technology, Beijing 100081, China
2 MOE Key Laboratory of Optoelectronic Imaging Technology and Systems, Beijing Institute of Technology, Beijing 100081, China
We implement Monte Carlo-based parallel ray tracing to achieve quick irradiance evaluation for freeform lenses with non-uniform rational B-splines (NURBS) surfaces. We employ the inverse transform sampling method to sample rays uniformly from the Lambertian light source and adopt the analytical form of the B-spline basis function to achieve fast surface interpolation. When performing parallel calculations for the intersections between the rays and the NURBS surfaces, we propose a parameter transformation method to avoid the parameters escaping from the defined range in the iteration process. Simulation results of two complex picture-generating freeform lenses show that our method is fast and effective.
propagation methods computation methods nonimaging optics lenses Chinese Optics Letters
2023, 21(5): 052201
Author Affiliations
Abstract
In this letter, a new analytical method is presented to calculate of the semiconductor optical gain coefficient. This method is particularly suitable for theoretical analyses to determine the dependence of semiconductor gain on the total carrier density and temperature in the semiconductor lasers. Also, the optical gain functions for semiconductor optical gain coefficient are presented analytically. The analytical evaluation is verified with numerical methods, which illustrates the accuracy of these obtained analytical expressions.
140.0140 Lasers and laser optics 140.3380 Laser materials 140.5960 Semiconductor lasers 080.1753 Computation methods Chinese Optics Letters
2014, 12(8): 081404
Author Affiliations
Abstract
A method of detecting dry, icy and wet road surface conditions based on scanning detection of single wavelength backward power is proposed in this letter. The detector is used to receive the backward scattered power which changes with the incidence angle. The relationship between backward power and incidence angle is used to find out the effective angle range and distinguish method. Experiment and simulation show that it is feasible to classify these three conditions within incidence angle of 5.3 degree.
080.1753 Computation methods 040.0040 Detectors 280.1350 Backscattering 290.5880 Scattering, rough surfaces Chinese Optics Letters
2014, 12(5): 050801
Author Affiliations
Abstract
1 Department of Physics, School of Science and Engineering, Ateneo de Manila University, Loyola Heights, Quezon City 1108, Philippines
2 Department of Mathematics, School of Science and Engineering, Ateneo de Manila University, Loyola Heights, Quezon City 1108, Philippines
A qualitative method to analyze wavefront aberrations is presented. Aberrations of the primary type, expressed in their matrix forms, are used to write the generalized ray transfer matrix of an optical component. The aberrations were treated collectively by examining the pseudospectra of an augmented matrix constructed from the aberration matrices. Results show that aberrations can be distinguished and relative strengths pronounced using this qualitative method.
像差 计算方法 近轴光学矩阵方法 080.2730 Matrix methods in paraxial optics 080.1753 Computation methods 080.1005 Aberration expansions Chinese Optics Letters
2010, 8(11): 1022
