1keV-200MeV A>24核子唯象定域和非定域球形核光学势的最新进展

简要介绍了核子唯象定域和非定域球形核光学势的最新进展。The progress of 1 keV-200 MeV A 〉 24 nucleon local and non-local spherical optical potential is briefly introduced.     

1keV—200MeV A>24核子唯像定域和非定域球形核光学势

简要介绍核子唯像定域和非定域球形核光学势的最新进展.     

LED绿色照明及其非成像光学设计

介绍了新一代LED光源的优点和缺陷．回顾了非成像光学的历史以及自由曲面在半导体LED照明中的应用,同时介绍了LED准直光源和LED光源产生均匀照度的光学设计方案．     

宽谱热光偏振态的统计描述

本文从宽谱热光光振动在垂直于光波传播方向的平面内的两个正交分量联合统计性质出发,导出偏振度概念,给出该两个正交分量在各种偏振态下的联合概率密度函数,从而全面描述了宽谱热光的偏振现象。 关键词：     

非致冷焦平面热成像技术

简要介绍了三种非致冷红外探测器的技术途径和发展现状。从系统原理提出ＵＦＰＡ热像仪的设计概念以及必须解决的几个关键技术。分析ＵＦＰＱ的性能极限和系统的性能水平,并与第一代轻型热像仪的ＭＲＴＤ曲线进行比较。     

定域与非定域的玻耳兹曼分布

对分别适用于定域与非定域系的两种玻耳兹曼分布，从推导和热力学公式等方面作了区分。     

基于非成像光学的发光二极管汽车后转向灯透镜设计

针对现有发光二极管（LED）汽车后转向灯存在的配光性能不准确、能量利用率低等问题,设计了一款准直配光一体化的LED后转向灯透镜。该透镜根据非成像光学原理和斯涅尔定理,通过迭代求解的方法设计而成,其高度为8．32mm,直径为12．64mm。利用光学软件TracePro对实际光源和后转向灯透镜进行光线追迹模拟,结果表明：在z方向4-80°,Y方向4-80。的矩形区间,发光强度均大于1．6cd;在x方向±20°,Y方向±10°内发光强度呈近似矩形分布,且各测试点结果均满足GB17905-2008要求。该透镜可精确控制LED发出光线,有利于提高配光性能及能量利用率。     

基于稀疏阵赝热光系统的强度关联成像研究

强度关联成像在近几年取得很大的突破,其应用价值越来越明显。以随机涨落的热光作为光源是强度关联成像的前提。目前常使用激光穿过旋转的毛玻璃产生赝热光。鉴于使用毛玻璃产生赝热光的局限性,提出了使用稀疏阵独立子光源产生赝热光,并在这种光源结构下讨论了基于线性关联算法的强度关联成像和基于稀疏约束非线性算法的强度关联成像的异同。     

关联光学新进展

文章综述了利用光学自发参量下转换过程产生的纠缠双光子态和热光源的空间关联性,实现“鬼”成像、“鬼”干涉、亚波长干涉和非定域双缝干涉等实验的研究进展,以及其中涉及的争论问题.     

Visibility enhancement in two-dimensional lensless ghost imaging with true thermal light

We report an experimental demonstration of two-dimensional(2D) lensless ghost imaging with true thermal light. An electrodeless discharge lamp with a higher light intensity than the hollow cathode lamp used before is employed as a light source. The main problem encountered by the 2D lensless ghost imaging with true thermal light is that its coherence time is much shorter than the resolution time of the detection system. To overcome this difficulty we derive a method based on the relationship between the true and measured values of the second-order optical intensity correlation, by which means the visibility of the ghost image can be dramatically enhanced. This method would also be suitable for ghost imaging with natural sunlight.     

Resolution and visibility of two-color pseudothermal lensless ghost imaging

Two-color (or nondegenerate-wavelength) lensless ghost imaging using pseudothermal light source is investigated theoretically by use of classical optical coherence theory. We find that for two-color pseudothermal lensless ghost imaging the visibility and resolution is determined by (Δ) the product of the wavelength and the corresponding path length rather than the wavelength for each path or the path length. We also confirm our theoretical conclusion by numerical simulations. The result shows we must make a trade-off between resolution and visibility in devise practical experiments, as the resolution of the imaging can be improved by decreasing Δ but with visibility getting poor, and vice versa.     

液晶自适应光学视网膜校正成像技术研究

为了实现对人眼视网膜的高分辨率成像,解决偏振能量损失、成像视场小和普适性差等问题,对液晶自适应光学技术及其在人眼视网膜成像中的应用进行了研究。通过开环光路的设计方案,避免了闭环液晶自适应系统的偏振光能量损失;在光路中加入可变视场光阑,利用小视场照明进行波前探测、大视场照明进行像差校正和成像的方法扩大了成像视场;使用脉冲光照明的方案减小曝光量;通过偏振光照明提高能量利用率、等效无穷远视标配合补偿镜以及改进后的视标提高盯视稳定性等一系列方法,提高系统普适性。校正后成像的清晰度和对比度获得了明显提高;高分辨率眼底成像视场直径从200 μm扩大到500 μm;曝光量减小到原来的1/2~1/3;对前期难以获得清晰成像的样本,取得了效果良好的视网膜视觉细胞自适应图像。     

Subwavelength Fourier-transform imaging without a lens or a beamsplitter

The fourier-transform patterns of an object are usually observed in the far-field region or obtained in the near-field region with the help of lenses. Here we propose and experimentally demonstrate a scheme of Fourier-transform patterns in the Fresnel diffraction region with thermal light. In this scheme, neither a lens nor a beamsplitter is used, and only one single charge coupled device(CCD) is employed. It means that dividing one beam out of a light source into signal and reference beams is not as necessary as the one done by the use of a beamsplitter in usual ghost interference experiments.Moreover, the coincidence measurement of two point detectors is not necessary and data recorded on a single CCD are sufficient for reconstructing the ghost diffraction patterns. The feature of the scheme promises a great potential application in the fields of X-ray and neutron diffraction imaging processes.     

MWIR imaging experiments with large F-number optics on LEO spacecraft

To determine the feasibility of spacecraft imaging in the mid-infrared region (3.0–5.0 μm) utilizing large F-number optics, we create a radiometric simulation of a low-Earth orbit (LEO) extended object, imaging background and noise, in order to predict the signal-to-noise ratio of such objects as viewed from a telescope during the daytime and terminator, etc. We find that the observation of Space Station and other extended targets utilizing large F-number optics for MWIR imaging is possible, given the right conditions. We have developed a large F-number infrared camera with cold stop matched, which is successfully applied to acquire LEO extended object images taken by a 1.23 m telescope. We get clear images of International Space Station, Tian-gong, etc. and our proposed the infrared imaging technology can be demonstrated to greatly improve the imaging ability of current ground-based Optoelectric (OE) telescope for the detection of space activities.     

High-order ghost imaging with N-colour thermal light

High-order ghost imaging with thermal light consisting of N different frequencies is investigated. The high-order intensity correlation and intrinsic correlation functions are derived for such N-colour light. It is found that they are similar in form to those for the monochromatic case, thus most of the conclusions we obtained previously for monochromatic Nth-order ghost imaging are still applicable. However, we find that the visibility of the N-colour ghost image depends strongly on the wavelength used to illuminate the object, and increases as this wavelength increases when the test arm is fixed. On the contrary, changes of wavelength in the reference arms do not lead to any change of the visibility.     

Simulated human eye retina adaptive optics imaging system based on a liquid crystal on silicon device

In order to obtain a clear image of the retina of model eye, an adaptive optics system used to correct the wave-front error is introduced in this paper. The spatial light modulator that we use here is a liquid crystal on a silicon device instead of a conversional deformable mirror. A paper with carbon granule is used to simulate the retina of human eye. The pupil size of the model eye is adjustable (3--7mm). A Shack-Hartman wave-front sensor is used to detect the wave-front aberration. With this construction, a value of peak-to-valley is achieved to be 0.086Λ, where Λ is wavelength. The modulation transfer functions before and after corrections are compared. And the resolution of this system after correction (69lp/m) is very close to the diffraction limit resolution. The carbon granule on the white paper which has a size of 4.7μm is seen clearly. The size of the retina cell is between 4 and 10μm. So this system has an ability to image the human eye's retina.     

Paraxial imaging electron optics and its spatial-temporal aberrations for a bi-electrode concentric spherical system with electrostatic focusing

The paraxial solutions play an important role in studying electron optical imaging system and its spatial-temporal aberrations, as was discussed in previous paper [1], but investigation of a bi-electrode concentric spherical system with electrostatic focusing directly from paraxial electron ray equation and paraxial electron motion equation has not been done before. In this paper, we shall use the paraxial equations to study the spatial-temporal trajectories and their aberrations for a bi-electrode concentric spherical system with electrostatic focusing.In the present paper, start from the paraxial ray equation and paraxial motion equation, the paraxial spatial-temporal trajectory of moving electron emitted from the photocathode has been solved for a bi-electrode concentric spherical system with electrostatic focusing. The paraxial static and dynamic electron optics, as well as the paraxial spatial-temporal aberrations in this system are then discussed, the general regularity of imaging in paraxial optical system has been explored. The paraxial spatial aberrations, as well as the paraxial temporal aberrations with different orders, have been defined and deduced, that are classified by the order of (?_z/?_ac)^1/2 and (?_T/?_ac)^1/2. Thus we get same conclusions about paraxial spatial and temporal aberrations as we have given in the previous paper and it completely shows that the paraxial spatial-temporal aberrations can be investigated directly from the paraxial ray equation and paraxial motion equation.     

基于光场一阶关联的时域成像

与通常利用二阶强度关联测量实现时域鬼成像不同,本文利用时域热光源借助干涉仪通过一阶关联实现时域成像.基于空域光束的近轴衍射和时域窄带脉冲在色散介质中色散之间的空间-时间二象性,在时域脉冲响应函数的基础上得到了表征一阶关联时域成像的强度表达式,分析研究了光源脉冲宽度和相干时间对成像可见度和分辨率的影响.结果一方面表明基于热光场一阶关联的时域成像在不需要额外色散补偿或消除条件下可以实现时域物体信号的再现,另一方面表明当光源脉冲宽度一定时,成像可见度随光源脉冲相干时间的增加而增加,但是成像分辨率逐渐降低,其中当光源脉冲宽度约为100 ps,相干时间约为0.5 ps时,间隔为20 ps,宽度为8 ps的时域矩形波型物体的成像质量(兼顾可见度和分辨率)较好.该结果对于基于热光一阶关联的时域成像在时序信号测量中的应用具有重要意义.