共查询到18条相似文献,搜索用时 140 毫秒
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自麦克斯韦鱼眼透镜理论模型提出后,长期以来学术界一直以为它只是一种绝对光学仪器,在实践中并没有应用的可能。但通过对麦克斯韦鱼眼微球透镜的理论研究表明,在一定条件下,它具有良好的成像性能和耦合效率。根据菲克定律推导出梯度折射率球透镜的折射率分布函数。并且熔制了含Li+硅酸盐玻璃和采用槽沉法以及Na+/Li+离子交换法制备直径为0.3—3.0mm的梯度折射率球透镜。通过干涉法测得了梯度折射率球透镜的折射率分布曲线,并研究了光线通过梯度折射率球透镜的轨迹。研究结果表明:在590℃,离子扩散系数为3.07×10-6mm2/s;所制备的梯度折射率球透镜的折射率分布是抛物线分布,并且和理论分析相吻合;梯度折射率球透镜的光线轨迹满足椭圆方程。 相似文献
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自聚焦(selfoc)纤维,也称梯度折射率(graded index)纤维,是一种新型光学纤维。一根自聚焦纤维,就相当于许多个微型透镜的组合,它可以把物空间内物体的象,在自聚焦纤维内经多次成象而得到传递<1>。由于自聚焦纤维内折射率分布是不均匀的,所以光线在其内的传播不是直线,而是沿曲线传播。此曲线称为光线的光迹,也可以称此曲线为光线。自聚焦纤维光线追迹问题,就是为了确定光线在其内传播的光迹,以便进一步研究自聚焦纤维传递光线和图象的规律和性能,为研制和应用新的自聚焦纤维提供数据。 相似文献
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焦距法测试自聚焦透镜折射率分布常数 总被引:1,自引:0,他引:1
本文介绍了一种测量自聚焦透镜折射率分布常数的方法─—焦距法,并进行了原理公式推导,和精度分析,其测量不确定度为±1×10 ̄(-3);其次,简要地介绍了实验方法。实验结果证明了焦距法是测量自聚焦透镜折射率分布常数的简单实用的方法,它具有装置简单、数据处理也不复杂的特点,是一种非破坏性的测试方法。 相似文献
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一、前言一般透镜,采用折射率为常数的均匀媒质,光线在媒质中是直线传播,因不同介质间的球形界使光线折射而产生透镜作用。近年来非均匀媒质透镜引起了人们的重视。特别是折射率沿径向变小的自聚焦透镜, 相似文献
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自聚焦透镜离轴耦合损耗理论研究 总被引:1,自引:0,他引:1
利用光线光学的原理分析了自聚焦透镜的光学性能,提出了求解自聚焦透镜离轴耦合损耗的数学模型,利用这一模型计算出了单模光纤与自聚焦透镜离轴耦合时的耦合损耗与模向距离的关系曲线,为自聚焦透镜离轴耦合的设计提供理论依据. 相似文献
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We describe a novel scheme for obtaining a superhigh numerical aperture gradient-index (SHNA GRIN) lens from multiple thin layers of two or more materials with large refractive-index contrast. Design procedures for the lens are described, including variation of the layer thickness to achieve focusing and of the thickness limit to reduce scattering loss. We use an exact numerical solution by the finite-difference time-domain method to evaluate the lens's performance. Specific examples of a SHNA GRIN lens with a SiO2-TiO2 material system designed for fiber coupling to a nanowaveguide are shown to have focusing FWHM spot sizes of 0.53-0.7 microm at lambda =1.55 microm (corresponding to a NA of approximately 1.6-1.1) with 2.7-2.4% more loss than an ideal continuous index profile GRIN lens. With this approach, a SHNA GRIN lens with a NA of > 1.5 and a length of <20 microm can be achieved with currently available thin-film deposition techniques. 相似文献
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Shuma Horiuchi Shuhei Yoshida Zenta Ushiyama Manabu Yamamoto 《Optical and Quantum Electronics》2010,42(2):81-88
Plastic gradient-index lenses produce clear images with negligible aberration and distortion. One of the methods for fabricating
these lenses involves pulling up the core fiber vertically from a polymer solution whose refractive index has been adjusted
to the desired value. Since the molecules from the solution diffuse into the inner layer, the monomer components are distributed
in the radial direction. The monomer distribution is fixed in the photopolymerization process, and this forming process is
repeated several times with adjusting the composition of the solution; hence, a specific refractive index distribution is
obtained. We considered a numerical model of the interdiffusion process and analyzed refractive index distribution that could
well reproduce the experimental results. Moreover, we employed the ray tracing method to calculate the modulation transfer
function and used the transfer function to evaluate the GRIN lens performance. Simulation results showed that our evaluation
method well duplicates the experimental results. We thus developed an integrated simulation method for the fabrication and
performance evaluation of GRIN lenses. 相似文献
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应用场光线传递方程,从鱼眼镜头的孔径光阑处,逆向追迹场光线传递方程,确定任意视场角场光线的初始位置,即光阑球差.正向追迹场光线计算鱼眼镜头系统物、像空间视场角之间的关系曲线;用多项式拟合求出关系曲线的解析表达式.通过反演运算,根据畸变图像复原物的图像分布,达到消除鱼眼镜头成像系统畸变的目的.最后,计算了一个160°鱼眼镜头光学系统的光阑球差和图像的畸变,并应用本文方法复原物的图像分布.计算结果表明:光阑球差的计算结果与真值的相对误差小于1%;复原的物方图像径向高度相对误差小于0.25%,说明本文计算鱼眼镜头像场像差的方法是可行的. 相似文献
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本文根据光线在球面上的折射公式及光线微分方程,研究了光线经两端面为球面的锥形梯度折射率透镜的传播和变换,基于光线传递ABCD矩阵,提出了球面端面的锥形梯度折射率透镜的一种等效光学系统.文中给出了该透镜的主平面、焦平面和焦距计算公式,以及近轴成像高斯公式.当锥度为零时即得到球面端面的柱形或径向梯度折射率透镜的相应结果. 相似文献
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A new schematic eye with aspheric surfaces and a radially varying refractive-index distribution lens is proposed. Image quality and spherical aberration are determined by use of ray tracing, and the results are presented as spot diagrams and compared with five existing model eyes. The proposed model provides the best image quality and lowest spherical aberration. 相似文献