按雷管的电性能核定发爆器的发爆能力

目前,引爆电雷管用的发爆器多种多样,电雷管的新品种亦不断出现,如我厂引进瑞典Nitro Nobel公司的雷管生产线现生产四种不同电性能的毫秒延期电雷管,其主要电参数列于附表。由于现行的发爆器的发爆能力是按照国家标准规定的电性能核定的(国际规定为20发电雷管的串联发火电流1.2A,发火冲能≤8.7mW·s/Ω),因此如简单地按发爆器标     

放映镜头的结构与使用注意事项

一、单片透镜的各种像差单片透镜存在许多缺点 ,它所成的像不能完全反映原物体的真实面貌。这种影像与原物体不一致的现象称为像差。透镜的像差可分为两种 ,由于透镜对各色光的折射率不同而引起的像差称色像差 ;由于透镜各部分对光的折射作用不同而引起的同一色光的像差 ,称单色像差。单色像差又分为球面像差、彗形像差、像散及像场弯曲和畸变等。1.球面像差(1)凸透镜的球面像差 :对凸透镜照射一束宽阔而与光轴平行的光线 ,经过透镜后不在光轴一点上汇集 ,这样一种被透镜折射后的光线焦点不一致的现象称为球面像差 ,如图 1所示。近轴光线在…     

GaAs激光窗口与透镜材料的制备原理和方法

目前,激光技术已广泛应用于医疗、测量、工业、军事和高科技等领域。在各种类型的激光器中,高功率CO2激光器在我国工业加工中例如:热处理、切割、焊接、表面合金化与涂敷等行业应用得已十分普遍。对于激光器和激光加工机来说,窗口和透镜则是十分关键的部件。从某种意义上讲,没有窗口就不会产生激光,没有透镜就无法进行激光加工。在有限的几种适合制作窗口和透镜的材料中,由于GaAs具有较好的综合性能因而受到人们的重视。本文仅对GaAs激光窗口及透镜材料的制备原理和方法做一简单介绍。     

凹凸透镜准直半导体激光器的极限

提出了用凹凸透镜校正半导体激光器(LD)光束的极限,给出了该极限的方程.分析了该极限随LD光束的线度、透镜的折射率和凹凸透镜镜面曲率半径的函数关系,并作出了函数关系图.     

无透镜全息光学元件匹配空间滤波波长比例相关器

本文描述了一种比例相关器光学图样识别系统。该系统中,一种无透镜匹配空间滤波器(其第二个傅里叶变换透镜和匹配空间滤波器记录于同一块板上)跟第一个博里叶变换透镜一起使用,而第一个傅里叶变换透镜也是一种全息光学元件。以一种波长记录匹配空间滤波器,以另一种波长得到相关。文中还报道其实验证明和输出相光信噪比数据,并就系统使用常规光学元件与使用全息元件时的噪声量进行了比较。     

分离式无起爆药安全点火系统在石油射孔中的应用

为解决石油射孔作业中起爆系统安全性问题,设计了一种分离式无起爆药点火装置并进行了发火、起爆可靠性测试及现场应用。测试结果表明:380 V交流电和600 V直流电均不会发火,能够可靠起爆导爆索及射孔弹,井下起爆实验均100%起爆。分离式无起爆药安全点火系统性能可靠,在未来石油射孔作业中有很大的应用前景。     

分离式无起爆药安全点火系统在石油射孔中的应用

为解决石油射孔作业中起爆系统安全性问题,设计了一种分离式无起爆药点火装置并进行了发火、起爆可靠性测试及现场应用。测试结果表明:380 V交流电和600 V直流电均不会发火,能够可靠起爆导爆索及射孔弹,井下起爆实验均100%起爆。分离式无起爆药安全点火系统性能可靠,在未来石油射孔作业中有很大的应用前景。     

透镜检测仪中自动聚焦方法的研究

在研究透镜光学参数通用测量仪的自动聚焦系统过程中,提出了一种新的、基于图像处理的自动聚焦方法,此方法适合光学透镜测量仪器自动聚焦过程且有目标图像结构简单、细节信息量少等特点,可以满足后续的测量需求。     

空间用平板形菲涅耳透镜的设计和光学效率研究

研究平板形菲涅耳太阳聚光透镜的光学问题,给出了线聚焦和点聚焦透镜的设计方法,讨论了设计参数对透镜光学效率的影响,为这类透镜的最优设计提供理论依据。     

抛物面型X射线组合折射透镜光学性能分析

抛物面型X射线组合折射透镜是一种适用于硬X射线波段的新型光学元件.由于采用抛物面型,可以消除球差,因而能够产生亚微米尺度焦斑并具有更好的成像性能.本文给出了旋转轴对称抛物面型X射线组合透镜的理论研究成果.首先,利用矩阵光学方法,推导了其精确的焦距公式,得到了薄透镜判定准则;其次,根据衍射理论,推导出焦点处的光强分布,得到其极限焦斑大小.最后,本文还给出了透过率和有效孔径的理论公式.针对用Al、Be、PMMA三种材料制作的抛物面型X射线组合折射透镜,本文给出了各个光学性能指标的数值计算沣结果.     

Correction of chromatic aberrations in GRIN endoscopes

A gradient-index (GRIN) endoscope can be constructed by substituting for the usual objective and relay sections suitable cylindrical index-distribution rod lenses. Currently available GRIN lenses exhibit large amounts of chromatic aberration. Axial color arises mostly from the relay lens, while lateral color is due to the objective lens. A negative lens cemented to a shortened GRIN relay lens can simultaneously correct axial and lateral chromatic aberrations with commercially available components. This correction system reduces the requirements for mechanical centration better than do color correctors that are incorporated into the ocular design. Monochromatic aberrations are also considered.     

Spherical gradient-index polymer lens with low spherical aberration

A sphere lens with a spherical gradient index (GRIN) was prepared by the modified suspension polymerization technique. GRIN spheres with quadratic- and linear-index distributions were obtained by two different methods to confirm the effect of the GRIN profile on the focusing property of the sphere lens. It was confirmed in both theory and experiment that the spherical aberration of such GRIN spheres was remarkably decreased compared with that of a homogeneous sphere.     

Gradient-index human lens as a quadratic phase transformer

The correspondence between the linear integral transform and the ray-transfer matrix of a first-order optical system is used to evaluate the transmittance function of gradient-index (GRIN) human lens regarded as a quadratic phase transformer. The size of the GRIN crystalline lens has been considered for redefining the effective transmittance function by the pupil function. The role that the GRIN nature of the human lens plays in the retinal image quality using the point spread function (PSF) is commented on. The simulation results show that the effective radius of the output face of the lens decreases with increasing thickness and that it is higher for flat end surfaces than for curved end faces. On the other hand, the simulation results also show, for small pupil sizes, that the GRIN nature of the human lens is a retinal image degradation source producing the spread of the PSF and that the curved end surfaces of the lens constitute a retinal image quality improve factor contributing to the narrowing of the PSF.     

轴位移法测定GRIN透镜的折射率分布系数

本文对GRIN透镜的精确光线追迹公式作了推导,介绍了轴位移法对透镜折射率分布的测量方法及相应的数据处理,并对测量误差进行了分析和计算,从而对测定GRIN透镜折射率分布提供了一种精确而且实用的方法。     

Fabrication method of ultra-small gradient-index fiber probe

Fabrication method and device of ultra-small gradient-index(GRIN) fiber probe were investigated in order to explore the development of ultra-small probes for optical coherence tomography(OCT) imaging.The beamexpanding effect of no-core fiber(NCF) and the focusing properties of the GRIN fiber lens were analyzed based on the model of GRIN fiber probe consisting of single-mode fiber(SMF),NCF and GRIN fiber lens.A stereo microscope based system was developed to fabricate the GRIN fiber probe.A fiber fusion splicer and an ultrasonic cleaver were used to weld and cut the fiber respectively.A confocal microscopy was used to measure the dimensions of probe components.The results show that the sizes of probe components developed are at the level of millimeter.Therefore,the proposed experimental system meets the fabrication requirements of an ultra-small self-focusing GRIN fiber probe.This shows that this fabrication device and method can be employed in the fabrication of ultrasmall self-focusing GRIN fiber probe and applied in the study of miniaturized optical probes and OCT systems.     

Adaptive model of the gradient index of the human lens. II. Optics of the accommodating aging lens

A simple, parametric model of the gradient refractive index distribution (GRIN) of the human lens with conicoid surfaces able to adapt to individual distributions as well as to the changes of the lens shape and structure with age and accommodation is presented. The first part of this work was published in a companion paper [J. Opt. Soc. Am. A24, 2175 (2007)]. It included the development of the mathematical formulation of the adaptive model; the validation of its customization capability by fitting, sample by sample, a set of in vitro refractive index distributions of lenses of different ages, ranging from 7 to 82 years, from the recent literature; and an average model of the (in vitro) aging crystalline lens. Here we extrapolate that in vitro GRIN model by assuming that the same structural parameters are valid for the living lens. Then, recent data of the changes of the shape of the aging lens with accommodation from the literature are used to build an aging and accommodating lens model. This is straightforward since the GRIN model adapts automatically to the chosen external lens geometry. A strong coupling was found between the adaptive GRIN distributions and the conic constants affecting the refractive power. To account for the lens paradox and the reported changes in lens spherical aberration with age and accommodation, age- and accommodation-dependent functions for the anterior and posterior internal conic constants were derived through optimization.     

Making fast cylindrical gradient-index lenses diffraction limited by using a wave-front-correction element

A wave-front-correction element (WFCE) is produced to make a cylindrical Ag-ion-exchanged gradient-index (GRIN) lens with a high numerical aperture (0.53) diffraction limited (wave-front error, 0.02lambda rms). The wave-front aberrations of the cylindrical GRIN lens are measured by a phase-shifting shearing interferometer, with a conventional microscope objective used as a compensation lens. The continuous surface relief of the WFCE is produced by a lithographic process. The wave-front-corrected GRIN lens is applied to collimate the strongly divergent light (57 degrees full diverging angle measured at 1/e(2) of maximum intensity) emitted by a high-power diode laser. The power irradiated into a full angle of 2 mrad can be enhanced by a factor of 1.8 with the WFCE.     

Birefringent properties of diametrically loaded gradient-index lenses

Gradient-index (GRIN) lenses have been widely used as collimators in various fiber-optic sensors and as optical coupling devices in components designed for optical communication systems. However, relatively little attention has been paid to the birefringent properties of GRIN lenses and the potential for using them as photoelastic sensing elements in optical transducers. Analytical and experimental results are described that were obtained for the intensity distribution produced by studying a GRIN lens by using a polariscope. The residual birefringence inherent in an unloaded lens is initially studied. The lens is then assumed to be diametrically loaded and the superposition is studied by the method of ray tracing. When the results obtained from the simulation for a Selfoc, 0.25-pitch lens are compared with experimental data, an excellent agreement is obtained. Intensity increases monotonically with load, confirming that the lens would be a good choice for the sensing element of an optical transducer designed as part of a strain or acceleration measurement system. The numerical simulation is then used to study the influence of residual stress on sensitivity.     

ABCD matrix of the human lens gradient-index profile: applicability of the calculation methods

The applicability of different approximate methods proposed to determine the paraxial properties of the gradient-index (GRIN) distribution resembling that of the human lens, by means of the system ABCD matrix, is tested. Thus, the parabolic-ray-path approximation has been extended to provide the ABCD matrix of a slab lens comprised of a rotationally GRIN medium. The results show that this method has good numerical stability, and it is also the easiest one in determining the Gaussian constants of the human lens GRIN profile.