三线阵测绘相机光学系统的杂光分析与计算

针对光学系统的杂光导致三线阵测绘相机成像质量下降的问题,根据光学系统的设计结果,对相机入口处的杂光能量、像面杂光辐照度、杂光系数等进行了分析与计算,提出了合理的杂光抑制措施。利用ThermalDesktop软件和Light—Tools软件,对三线阵立体测绘相机各光学系统进行分析与模拟计算,得到其杂光系数均小于5％。最后进行了光学实验,并利用面源法测试了杂光系数。检测结果验证了杂光分析与研究方法的正确性以及杂光抑制措施的可行性。     

一种折反式光学系统的消杂光设计

针对一种折反式光学系统相机遇到的消杂光问题,根据杂光计算结果对相机进行了消杂光设计,通过试验对杂光计算结果进行了验证,试验结果与计算结果吻合,验证了消杂光设计的正确性。进行消杂光设计后,相机的杂光系数满足设计指标要求,有效地减小了杂光对图像质量的影响。     

Active light noise filter by a differential operation

A method for an active light noise filter is proposed by using two identical light receivers. They work as a differential electrometer by a common mode connection. Therefore, only an output of a laser light incident upon one receiver can be obtained as a signal. It was found from the experiment that the light noise was reduced to about 0.6% in the usual light room and further the signal to noise ratio was improved up to 30 times at least as compared to a usual light shielding method. The method can then be effectively used under a well-lighted room such as a factory without noise light shielding cover.     

Optical design and optimization of light emitting diode automotive head light with digital micromirror device light emitting diode

This research proposes a new method for light emitting diode automotive headlight design with digital micromirror device (DMD). The optical design is advanced because of the following features. First, this optical design controls the angle of light pattern without light masking so as to achieve much higher light efficiency compared with traditional optical design for headlight systems. Second, in view of the tendency that the advanced light emitting diode automobile headlight is designed to be a low beam light module and a high beam light still needs an auxiliary lighting system, the optical system designed in this research, mainly adopting DMD module as high/low beam light switch, can switch on and off both the high and low beam lights. Because DMDs function of accepting a bidimensional image, high/low beam light patterns can be determined by DMD. Third, a light pattern will be created and compensated simultaneously by DMD, which might replace mechanical adaptive front-lighting system in the future because DMD takes advantage of fast response and simultaneous compensation. Fourth, a design using a multiple reflection curved mirror is employed in this research to adjust light energy distribution; therefore, the articulation of the light pattern can be enhanced. For this method, experimental results of light efficiency are up to 85%, which is superior to current products in the market.     

尘埃粒子计数器中光源对传感器光通量的影响分析

在Mie散射理论基础上，由单分散射的光强表达式导出在偏振光的入射条件下一定立体角内的散射光通量的表达式，并与自然光入射作比较。计算了在相同强度不同光源入射下，尘埃粒子计数器的两种常用散射光收集系统收集的散射光通量。结果表明：采用近前向散射光收集系统得到的光通量相等；而采用直角方向散射光收集系统时两者并不相等，且在平面偏振光入射时，收集的散射光通量还跟探测器中心与入射光偏振方向夹角有关。用MATLAB编程计算，得出了在探测器中心与偏振方向的夹角成90°或270°位置时，收集的散射光通量有极值的结论，为激光尘埃计数器传感器光学设计提供了依据。     

不同LED光质对人参种苗叶片生理特性和超微结构的影响

主要针对不同光质对人参种苗叶片生长影响的研究,从而探究人参工厂化育苗的优良光质,为提高种苗质量提供基础依据。试验设置六组处理,分别为白光（W,作为对照）、蓝光（B,450～470 nm）、红光（R,625～655 nm） 、绿光(G, 510～530 nm)、黄光(Y, 585～605 nm)、红蓝光(RB, R/B=4∶1),白光作为对照光源。试验结果表明,不同光质下生长的人参种苗叶片在外观形态、生理特性和细胞结构上都显现明显的差异。在叶面积的生长过程中,红蓝光和白光下的叶面积较大,红光次之,蓝光下最小;在叶绿素含量的分布中,添加蓝光的处理组明显高于对照组,说明蓝光对叶绿素的合成有关键作用,红光下叶绿素含量最低,表明红光不利于叶绿素的合成。蓝光、黄光和白光下叶绿素荧光电子效率较高,而在气孔特性上,绿光、红光和白光的气孔数量较多,单个气孔面积蓝光和红蓝光下较大。通过电镜下叶片超微结构的观察发现,不同光质对叶片的细胞结构产生了明显的影响,主要表现在线粒体和叶绿体的分布以及叶绿体的结构上,其中白光和蓝光照射下的线粒体和叶绿体数量较多,叶绿体片层结构垛叠数上也更紧凑丰富。另外,不同光质下生长的幼苗叶片衰老进程也产生了明显的差异,蓝光、红蓝光照射下衰老速度较快。综上所述,不同光质对于人参种苗叶片生长的影响各不相同,蓝光和红蓝复合光照射具有较多的优良性状和较好的生理参数,因此在应用和实践上还需要根据具体的需求制定相应的光质配比策略,以达到壮苗丰产的目的。     

细菌视紫红质的动态透射特性及其应用

细菌视紫红质 (Bacteriorhodopsin,简称 b R)是由嗜盐菌中提取出的一种光敏蛋白质 ,它是一种新型的生物光子学材料。我们测量的 b R膜在黄光和蓝光束分别照射下的非线性透射特性表明 ,在光照开始阶段 ,光的透过率随时间延长而增加 ,然后逐渐达到一个稳定值。黄光和蓝光的透过特性的不同是蓝光达到最大透过率的时间比黄光短。 b R膜在黄光和蓝光双光束同时照射下的非线性透射特性的计算结果表明 ,在某一固定蓝光光强 ,蓝光的透过光强随黄光强度的增加而减小 ,甚至变为零。这说明黄光对蓝光有抑制作用 ,即黄光可以调控蓝光的透过率。这一奇异的透射特性可以用做新出现事物滤波器     

用于投影机的发光二极管照明单元

目前的投影机光源——高压汞灯存在寿命短、色温高、存在有害光线、发热集中等缺点,严重制约了投影机进入家庭应用领域。发光二极管的最近发展为其作为高压汞灯的替代光源提供了可能性。提出了一种由一个发光二极管、一个准直镜、一个前蝇眼透镜和一个后蝇眼透镜组成的用于投影机的发光二极管照明单元,由数个照明单元加上会聚透镜则构成一个基本的照明系统。发光二极管的发光经准直镜压缩光束发散角后被前蝇眼透镜分割为多个细光束,会聚透镜将每个细光束都叠加会聚到显示芯片上,实现光能量的会聚和光场再分布．以满足投影机对光通量和光场均匀性等方面的要求,后蝇眼透镜用于与后续光路的匹配。作为照明单元的一个应用实例,文中分析了一种单片式硅上液晶投影机。     

Light intensity distribution of a new type of contact laser scalpel

The emergent light distribution of a new type of contact laser scalpel is measured in three different states using a light sensor. The relationship between the angle and the light intensity is analyzed. The results show that the strongest light is emitted from two sides and the front of the scalpel. The light from the front mainly plays a role of cutting. The light from two sides contributes to stanch the wound so as to remain a clear visual field during the surgery. It also helps to increase the cutting efficiency.     

准直物镜在变焦距镜头杂散光系数测试中的作用和影响分析

在对变焦距光学镜头进行杂散光系数测试的过程中,需要了解各测试环节的作用及对测量结果的影响。讨论了准直物镜使用与否对杂散光系数测量结果的影响。通过对杂散光形成机理的分析,将杂散光来源分为视场内与视场外两种,阐述不同来源杂散光的不同特点及这两种杂散光通过准直物镜后的状态。用两个参数不同的变焦距光学镜头在有无准直物镜两种情况下杂散光系数的测量结果,说明准直物镜在杂光测试中的作用。对于视场外入射光束形成的杂散光,准直物镜的使用与否对其测量结果影响巨大,而对视场内入射光束形成的杂散光影响很小,测量时可以利用准直物镜来判断光学镜头杂散光的来源。同时通过实验说明入射光线在准直物镜间的多次反射形成的杂散光约为1%,它可作为系统误差从测量结果中剔除。     

One-beam recording in a LiNbO3 crystal

We propose a new way to record images in a photorefractive LiNbO3 crystal. This method involves only a single object light without any reference light. We believe that the recording is attained by fanning holograms that result from interference between the object light and its scattered light. Although volume gratings are involved, the recorded pattern can be viewed not only with a laser light beam that is incident over a certain angular range but also with white light.     

微型平像场近红外光谱仪的消杂散光设计

设计和研制了结构紧凑、杂散光低的微型平像场近红外光谱仪。在分光系统设计中不采用附加杂散光遮挡装置的常规方法,而是在准直物镜前设置一块直径为8．5mm的平面反射镜,通过调节平面反射镜改变入射光束的空间角,使光束全部被准直镜接收,不再产生旁光,从而有效地消除系统内的杂散光,使仪器整体杂散光水平降低了1．13％。另外,该光谱仪选择线阵CCD作为探测器件,不再设置冷却系统也避免了平面光栅带有扫描旋转机构。由于使用CCD作探测器和新的消杂散光设计方法,该光谱仪实现了微型化。     

大面积三角形探测光幕灵敏度空域分布分析

分体式探测光幕实现室内靶道弹丸初速测试时,探测光幕的灵敏度直接影响初速测量的精度。研究了线光源配接镜头式接收装置组成大面积三角形探测光幕的灵敏度分布,考虑光学镜头离轴效应和线光源随距离衰减现象,将探测光幕内不同位置处光照度等效到线光源处,假设光幕厚度均匀,弹长始终大于幕厚,弹丸遮挡探测光幕所形成的面积与当前区域光幕截面积之比等效为弹径与当前位置处光幕宽度之比。在4.8 m×2.4 m 三角形探测光幕上进行理论仿真与实弹试验验证,仿真分析与实弹试验结果一致,靠近镜头处灵敏度大,远离镜头处灵敏度小,且关键探测区域内模拟电压幅值标准差为0.05 V,均匀性符合测试要求。研究结果可为三角形探测光幕的工程设计提供参考。     

用于LCD背光模块的LED光源转成线光源设计研究

将液晶显示器背光模块的导光板向前延伸5 mm,利用该区设计一扩光区使得LED点光源经过该区可获得两次的扩光效果,达到将点光源转成近似冷阴极管(CCFL)的线光源效果,并以3 in液晶显示器面板进行模拟,模拟结果表明导光板的出光均匀度可以达85%以上.     

Luminance contrast, a new illumination technique in light microscopy: Optical basics, practical evaluations, further developments

Luminance contrast is a new illumination technique in light microscopy recently developed by the author, which leads to extraordinary contrast effects, enhanced focal depth and supramicroscopic resolution when transparent stained or unstained specimens are examined.This method is characterized by a small illuminating light beam running centrically to the specimen, so that the specimen is illuminated very homogenously. Within the objective, the illuminating beam is blocked by a small light stop. When all parts of the illuminating light are totally blocked, the background is completely dark; when small parts of the illuminating light pass the light stop, the background is moderately brightened.The microscopic image is a result of scattered light components, which are bent or reflected by the specimen. When the illuminating light is not completely blocked by the light stop, the transmitted illuminating components interfere with the scattered light components coming from the specimen.Additional three-dimensional effects are achievable when the illuminating light passes the specimen obliquely.The resulting variants of illumination are similar to dark field, negative phase contrast and interference contrast. In all modes of luminance contrast the specimen is illuminated very homogenously so that it appears as a self-luminous, fluorescent body – similar to fluorescence microscopy.Luminance contrast can be carried out when mirror objectives are used or common objectives containing glass lenses are equipped with individually adjusted light stops.Further aspects of technical developments are discussed in full details.     

空气中尘土的浓度测量及其应用

当一定频率的光照到特定的金属表面时，金属会产生光电子并产生光电流，其光电流的大小与光强成正比，而光强与发射光的光强和光在传播过程中的煤质有关。当射光强一定时，其光电流大小与媒质有关。当光线穿过一定浓度尘土的空气时，其光电流大小与媒质浓度成反比，根据这一原理，我们可以通过测量光电流的大小来测量尘土的浓度。     

不同光质对人参愈伤组织生长及皂苷含量的影响

人参主要依靠大田栽培,耗时长,利用植物组织培养技术不仅可以缩短育种年限,还可以用来生产次生代谢产物.在组织培养中,光质对于药用植物次生代谢产物的影响受到了人们广泛关注.以人参愈伤组织为试材,采用超高效液相色谱法,研究了不同光质(包括红光、红蓝光、蓝光、绿光、黄绿光)对人参愈伤组织生长状态、总皂苷及9种皂苷单体Rg1,R...     

光固化成型中紫外光源-光纤耦合研究

CPS(Compact Prototyping System)光固化成型系统中,以紫外灯作为光源,通过光纤传输紫外光到液面,进行扫描成型.光源通过椭球反射镜集光,在焦点处与光纤耦合,提高了光源-光纤的耦合效率,在实际的光源-光纤耦合中,光纤的装配存在着角度误差、离焦误差、离轴误差三种形式,这些误差影响传输光束的传输效率.在光纤的输出端,聚焦透镜将紫外光汇聚,光斑尺寸更小,能量更加集中.CPS成型机中使用的紫外光的能量并不是均匀分布的,光斑的中心能量高,边缘能量低,不同的能量分布影响树脂固化的形貌和质量.     

Measuring Light Field of Light Source with High Directional Resolution Using Mirrored Ball and Pinhole Camera

This paper presents a method of measuring a light field of a light source with high directional resolution using a mirrored ball and a pinhole camera. The light field describes a spatial and directional distribution of radiances from the light source. The directional distribution is expanded by a reflection on the mirrored ball, and the radiances are measured by a charge-coupled device (CCD) camera with a pinhole lens. The light source is laterally moved by a robot arm to measure the directionally expanded light field, and each pixel on a CCD can obtain the radiances from the light source through the pinhole lens with high directional resolution. The light field is estimated from the pixel value and the position of each pixel using a ray tracing technique. The light field of a krypton lamp was experimentally measured by the proposed method, and the accuracy of the measurement was evaluated against the irradiances measured by a spectro-radiometer at sample points.     

Squeezing properties of light field in the process preparing Raman atom laser

In this paper, the squeezing properties of the probe light field in the process preparing Raman-type atom laser via stimulated Raman transition of the sodium atom Bose-Einstein condensate (BEC) interacting with two light beam of a weaker squeezed coherent probe light and a stronger classical pump light are studied. The results show that the probe light can be periodically squeezed. The squeezing period is related to the mean number of atoms in trap, the strength of interaction between squeezed light and BEC atoms, and the detuning of the light, and the squeezing depth is determined by the initial squeezing factor of the probe light.