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101.
介绍了计算机光学零件图自动绘制软件系统的功能,给出了用该软件完成的光学零件图图样,对程序设计过程中的难点及处理方法也进行了详细阐述。 相似文献
102.
103.
测量平动物体位移的光纤传感器已有许多报导,而测量转动物体位移的光纤传感器却很少,从原理和实验两方面对后一问题作了研究。 相似文献
104.
介绍了一种光纤式机器人触觉传感器,分析了这种传感器的静态特性,并通过理论分析和实验研究提出了一种消除干扰的方法。实验结果证明,传感器的最大绝对误差为0.053kg,相对误差为0.62%。 相似文献
105.
光盘用光学头物镜性能的综合评估 总被引:1,自引:0,他引:1
论述了采用波象差均方根、点扩展函数、光学传递函数对高次旋转对称非球面光学头物镜性能进行综合评估的方法。作者在正则坐标理论基础〔1〕上编制了光学头物镜性能综合评估软件。给出了评估实例。 相似文献
106.
SUNHongxia LUHongchang 《半导体光子学与技术》1998,4(2):74-77,98
Using the ray trace method,three-section semiconductor lasers are studied .An analytic expression of output power for the three-section semiconductor lasers is derived for the first time.Frome this expression,threshold condition is also obtained. 相似文献
107.
Statistical studies of branched ester latex and paint properties 总被引:3,自引:0,他引:3
R. A. Prior W. R. Hinson O. W. Smith D. R. Bassett 《Progress in Organic Coatings》1996,29(1-4):209-224
Vinyl versatate, butyl acrylate and 2-ethylhexyl acrylate were compared as comonomer, for colloid-stabilized vinyl acetate latex polymers to assess their impact on latex coating properties. Vinyl versatate afforded advantages in scrub resistance, gloss, hydrophobicity and higher glass transition temperatures. Butyl acrylate developed better wet adhesion efficiency, gel content and hiding efficiency. 2-Ethylhexyl acrylate offered performance comparable to butyl acrylate in hiding efficiency, lowering copolymer glass transition temperatures, and gloss development. Combinations of these monomers, in many instances, afforded a better balance of performance properties than individual monomers alone. In the subject study, a simplex-centroid design was utilized to statistically map polymer compositions for determining the effect of comonomer composition on latex and paint film properties. In addition to developing contour maps of polymer and paint properties as a function of composition, a technique for studying structure-property relationships is presented. 相似文献
108.
Iron pyrite films prepared by sulfur vapor transport 总被引:4,自引:0,他引:4
Iron films deposited via thermal evaporation, with a thickness between 100 and 250 nm, were converted into FeS2 by open sulfur transport using nitrogen as a gas vector. The films thus obtained constituted a single pyrite phase and were optically highly absorbing. The sulfurization process was optimized. As a result, sample temperature and conversion time were found to be the major determining parameters. The films were characterized using several methods. The crystallinity and phase identification were determined by X-ray diffractometry. Scanning electron microscopy showed a homogeneous surface of both iron and pyrite layers. Optical transmission measurements confirmed the highly absorbing character of FeS2 and allowed the determination of direct (1.35 eV) and indirect (0.82 eV) transitions. 相似文献
109.
J. Martan N. Semmar C. Boulmer-Leborgne 《International Journal of Thermophysics》2007,28(4):1342-1352
An optical system for fast IR radiometry designed for investigations of thin film thermal properties and pulsed laser melting
was analyzed in this work. A methodology for determination of the view factor from calibration measurements was developed.
The view factor (0.0255) of the optical system containing two paraboloid mirrors was determined experimentally from calibration
measurements on pure metals and metallic alloys. The knowledge of the view factor was then applied to normal emissivity investigations
at IR wavelengths. The emissivity of tungsten films prepared by magnetron sputtering was determined for different deposition
conditions, varying between 0.036 and 0.071. Liquid phase emissivities of Cu, Mo, Ni, Si, Sn, Ti, and steel were also determined
and were found to be higher than solid-state emissivities as predicted from the literature. A knowledge of the liquid-state
emissivity of silicon enabled recalculation of the IR signal evolution to the temperature evolution, during and after a nanosecond
laser pulse. This was not possible by use of the usual calibration because of silicon’s semi-transparent behavior in the IR
range (1–10 μm) in the solid-state phase. 相似文献
110.
The optical and thermal properties of prepared poly(ethylene oxide)/MnCl2 films were studied as a function of MnCl2 concentration at room temperature. The observed optical energy gap (Eopt) and energy gap tail (ΔE) were determined from the measured absorption spectra. It was found that the optical energy gap decreases with MnCl2 concentration, and the absorption coefficient reduces sharply at concentration of 5 wt% MnCl2 compared with the neat PEO. Differential scanning calorimetry (DSC) measurement shows that the heat of fusion increases with the MnCl2 concentration, while the melting point decreases. Correlation between the observed optical energy gap and heat of fusion is presented. 相似文献