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81.
A different approach, aiming to achieve the constant blur status of point-spread function (PSF) at a certain defocused plane,
is described. The correlation between the two PSF is used to control the PSF blur similarity, and simultaneously the Strehl
ratio is also used to control the PSF blur minimization. By designing the PSF so that it is significantly insensitive to defocus
or related defocus quantity, for example, due to temperature change, all the constantly blurred images can be accurately de-blurred
by a simple inverse restoration filter for an adequate range of defocus. We refer to that as “software lens compensation”
and apply a design method to solve the athermalization of middle wavelength infrared (MWIR) imaging systems. The resultant
PSF is almost invariant in the temperature range from −10 to 50°C at the same focal plane. Consequently, the constant blur
spot can be removed by a simple digital signal processing. Thus, clear and sharp de-blurred images at different temperatures
are obtained. 相似文献
82.
Effect of the defect on the focusing in a two-dimensional photonic-crystal-based flat lens
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We have investigated in detail the influence of defect on the focusing of electromagnetic waves in a two-dimensional photonic-crystal flat lens by using the finite-difference time-domain method. The result shows that many focusings can be observed at the symmetrical positions when a defect is introduced into the lens. Furthermore, the wave-guides in the lens can confine the transmission wave effectively and improve the quality of the focusing. 相似文献
83.
复眼照明系统利用复眼透镜,可实现高亮度和较好的亮度均匀性,并且有较成熟的偏振处理方法,在投影系统特别是基于偏振光的投影系统中能提供比光棒照明系统更加高的亮度和好的均匀性的画面,使得光能利用率和图像均匀性有了较大的提高。在对复眼照明系统的原理进行分析的基础上,设计了一种用于投影光机的复眼照明系统,并用Matlab对该系统进行了光线追迹的仿真程序设计。对复眼照明系统的光线追迹进行了仿真。实际应用证明,在LCoS中采用本方案设计的照明系统比光棒照明系统具有更高的亮度和更好的均匀性。 相似文献
84.
193nm光刻曝光系统的现状及发展 总被引:3,自引:0,他引:3
投影曝光工艺是集成电路制造过程中的关键环节,曝光系统的工艺水平已成为衡量微电子制造技术的重要标志。重点介绍了目前193nm光刻设备曝光系统的发展现状和趋势,以及为提高曝光质量所采用的相关分辨率增强技术;通过分析曝光系统的构成和其中的关键技术,探讨了国内研制相关曝光设备所面临的挑战。 相似文献
85.
梯度折射率棒透镜的色差模型 总被引:1,自引:0,他引:1
本文提出一个梯度折射率棒透镜(GRIN-RodLens)的色差模型,并运用本模型合理地解释了在色差测量过程发现的各类色差现象. 相似文献
86.
本文介绍了在YG366高速抛光机上进行的透镜不胶盘单件抛光技术。这一新的抛光方法比弹性成盘法和刚性成盘法有许多优点:它省掉了许多辅助工序,缩短了抛光时间,所以生产周期短,效率高,成本低。同时给出了根据透镜的结构参数进行生产技术准备和评估抛光过程稳定性的公式。最后提出了进一步改进的设想。 相似文献
87.
The present paper considers the magnifying power and aberration properties of three different catadioptric magnifying systems
useful for application as simple hand-held microfiche readers. These are in the form of a plano-convex lens, a meniscus lens
and an achromatic doublet lens and all their outer surfaces have been coated with a semi-reflecting film so that they behave
like catadioptric elements. These can be designed to give magnification in the range of 15 × to 25 × with sufficient eye relief.
Using such magnifiers, it is possible to read microfiche having frame sizes of 16 × 12 mm and 12 × 9 mm. The cemented achromatic
doublet coated on the outer surfaces seems to give a very good image for use in microfiche reader. 相似文献
88.
In the paraxial optics approximation, we have studied the transformation of a simple Gaussian beam of light obliquely incident on an isotropic lens for the case where the axis of the beam and the principal optical axis of the lens are crossed straight lines. The data obtained are compared with the corresponding results for the case where the axes of the beam and lens are coplanar. 相似文献
89.
Zhanguo Chen Gang Jia Yunlong Liu Zhifa Wu Chao Zhao Maobin Yi 《International Journal of Infrared and Millimeter Waves》2001,22(5):695-702
In this paper, all electro-optic solid immersion lens (EOSIL) is introduced, which is made of GaAs. A reflecting external electro-optic measuring system based on the EOSIL is built. With a hemispherical GaAs EOSIL used as the external probe, 0.7 µm spot size is obtained when the wavelength of the probing beam from a laser diode is 1.3 µm and a microscope objective with 0.3 numerical aperture is used. The principle of the measuring system is analyzed by Jones matrix. By using the system, the electrical signals propagating on a microstrip transmission line are successfully measured. The voltage sensitivity about 5 mV/
is measured when 10 kHz sinusoidal electric signal is applied on the microstrip line. 相似文献
90.