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91.
i线投影光刻曝光系统的光学设计 总被引:3,自引:1,他引:2
叙述具有同轴对准特性的光学投影物镜双远心结构和均匀照明光学系统原理。为了满足i线光刻所需的光学传递函数要求,讨论了光刻分辨率和数值孔径的关系。设计了一种新的双远心投影物镜,其数值孔径NA=0.42,放大倍率M=-1/5,像场尺寸15mm×15mm(直径21·2mm),共轭距L=602mm。用光学设计程序ZEMAX-XE计算此i线物镜的像质。设计结果说明,整个视场内波差<λ/4,MTF>0.55,当空间频率为715pairlines/mm,使用波长为365士3nm时。可以实现0.7μm光刻分辨率;照明均匀器,由81个小方型透镜组成一方列阵。用本文模拟计算软件OPENG计算被照像平面上的光能分布,说明实际系统的照明不均匀性为土2%。 相似文献
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Hariyadi Soetedjo O. Mohd Nizam Idris Sabtu J. Mohd Sazli Ashaari Yusof Y. Mohd Razman A.F. Awang Mat 《Microelectronics Journal》2006,37(6):480-482
Various pseudomorphic High Electron Mobility Transistor (pHEMT) structures of AlGaAs/InGaAs alloys have been observed their current-voltage behavior. The tungsten probes were used for a measurement the structures by ramping the voltage from −5 to 5 V and measure the electrical current. Measurement was carried out at room temperature and also under optical illumination. From the measurement, the electrical current was found to increase as the increase of Al content in the AlGaAs alloys layer in the pHEMT structure. This phenomenon was supported by the decrease of sheet resistance as obtained from Hall effect measurement. Under visible light illumination, the current-voltage behavior of pHEMT structure was observed to vary as the light power density was varied for 0, 25 and 55 μW/cm. 相似文献
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Károly Bezdek 《Periodica Mathematica Hungarica》2006,53(1-2):59-69
Summary The Illumination Conjecture was raised independently by Boltyanski and
Hadwiger in 1960. According to this conjecture any <InlineEquation ID=IE"1"><EquationSource Format="TEX"><![CDATA[<InlineEquation
ID=IE"2"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"3"><EquationSource Format="TEX"><![CDATA[$]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>d$-dimensional
convex body
can be illuminated by at most $2^d$ light sources. This is an important
fundamental problem. The paper surveys the state of the art of the Illumination
Conjecture. 相似文献
99.
Many studies have been published on the use of TiO2 as a photocatalyst, which decomposes various organic compounds under UV illumination by generating various radicals. The purpose of the present study was to evaluate the photocatalytic bactericidal effects of variously treated titanium surfaces on Escherichia coli K-12. The specimens were fabricated from grade 4 commercially pure titanium, 12 mm in diameter and 1 mm in thickness. Five different surfaces were prepared (MA: machined surface; AO: anodized at 300 V; NO: NaOH-treated; NW: NaOH- and water-treated; and HT: heat-treated). Surface analysis was performed using scanning electron microscopy, optical interferometer, and thin-film X-ray diffractometry. Photocatalytic activity of each group was confirmed by degradation of methylene blue (MB). The antibacterial activity was assessed by calculating the survival ratio in a drop of a culture of E. coli placed on the surface under UV illumination. Significant photocatalytic activity and bactericidal effects were observed on the titanium surfaces of AO and NW, regardless of the surface roughness (P < 0.01). The group with anatase was the most susceptible to the photocatalytic effect, while the surface without anatase showed the least susceptibility. Based on this in vitro study, the crystallography of the oxide layer on its titanium surfaces is an important factor affecting the photocatalytic bactericidal activity. 相似文献
100.
传统的人脸识别方法对待识别人脸图像的质量要求较高,而且要求所采集的人脸图像的光照情况与人脸训练库的光照情况的差异不能太大,这就限制了人脸识别系统运行的环境条件,从而限制了人脸识别的应用。为了降低人脸识别对环境条件的要求,真服光照对人脸识别的影响。本文分析了人脸图像的幅频特性和相频特性,提出了频域光照归一化的人脸识别方法,使得对任何光照条件下采集的图像经过归一化后,光照情况与训练库中的图像完全相同,同时保留了人脸的可区分性。因为人脸之间差异的信息量一般较少,故本文运用最小非零特征向量作为人脸特征,通过实验仿真,与传统方法相比本文人脸识别方法对光照变化具有鲁棒性。 相似文献