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131.
Electrowetting-Based Variable-Focus Lens for Miniature Systems 总被引:1,自引:0,他引:1
B. H. W. Hendriks S. Kuiper M. A. J. VAN As C. A. Renders T. W. Tukker 《Optical Review》2005,12(3):255-259
The meniscus between two immiscible liquids of different refractive indices can be used as a lens. A change in curvature of this meniscus by electrostatic control of the solid/liquid interfacial tension leads to a change in focal distance. It is demonstrated that two liquids in a tube form a self-centred variable-focus lens. The optical properties of this lens were investigated experimentally. We designed and constructed a miniature camera module based on this variable lens suitable for mobile applications. Furthermore, the liquid lens was applied in a Blu-ray Disc optical recording system to enable dual layer disc reading/writing. 相似文献
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133.
一种全场三维共焦检测的新方法 总被引:11,自引:1,他引:10
提出了一种利用微光学阵更合成器件实现全场三维面形并行检测、记录的共焦方法。此方法的关键是,在共焦系统中引入一一微光学耻列合成器件来产生一点光源阵列,实现了对同一一剖面同时并行检测,并首次采用了CCD面阵像元取代上孔光阑直接截取三维信息光强。本文讨论了该方法的三信息检测原理,响应关系,给出了初步的实验结果和三维重构图。 相似文献
134.
首次使用双狭缝相机对“神光”装置南路倍频线聚焦激光打靶所形成的线状等离子体均匀性进行了监测。由于实验条件的限制,相机的测量位置不太理想。为此,我们进行了修正,本文即是在修正基础上给出实验结果。修正后的结果表明,“神光”装置南路倍频线聚焦激光打靶部分发次所形成的线状等离子体均匀性不够理想。 相似文献
135.
136.
转镜式高速相机扫描速度及其不均匀性测量 总被引:1,自引:0,他引:1
介绍了高速相机扫描速度不均匀性产生的原因、扫描速度测量的方法,简要地介绍了测量系统的工作原理,测时精度达到3ns,测速精度达到 3,最后给出了测量 GSJ型和SJZ-15型相机的结果。 相似文献
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138.
Bruno Debus Dmitry Kirsanov Irina Yaroshenko Alla Sidorova Alena Piven Andrey Legin 《Analytica chimica acta》2015
In clinical analysis creatinine is a routine biomarker for the assessment of renal and muscular dysfunctions. Although several techniques have been proposed for a fast and accurate quantification of creatinine in human serum or urine, most of them require expensive or complex apparatus, advanced sample preparation or skilled operators. To circumvent these issues, we propose two home-made platforms based on a CD Spectroscope (CDS) and Computer Screen Photo-assisted Technique (CSPT) for the rapid assessment of creatinine level in human urine. Both systems display a linear range (r2 = 0.9967 and 0.9972, respectively) from 160 μmol L−1 to 1.6 mmol L−1 for standard creatinine solutions (n = 15) with respective detection limits of 89 μmol L−1 and 111 μmol L−1. Good repeatability was observed for intra-day (1.7–2.9%) and inter-day (3.6–6.5%) measurements evaluated on three consecutive days. The performance of CDS and CSPT was also validated in real human urine samples (n = 26) using capillary electrophoresis data as reference. Corresponding Partial Least-Squares (PLS) regression models provided for mean relative errors below 10% in creatinine quantification. 相似文献
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140.
An experimental technique is presented for measuring the heat dissipation and localization during cyclic loading of materials.
The temperature field is measured by a number of thermistors and an infrared camera, which scans the specimen surface continuously.
The specimen is mounted inside an isothermal chamber. The measured whole-field temperature can be used for detection of damage
propagation and localization. The resolution of the technique under various boundary conditions is discussed using a onedimensional
model for the heat loss under steady-state conditions. Applications of the technique are demonstrated for specimens made of
fiber-reinforced ceramic and polymer matrix composites (PMCs). A methodology is proposed for measuring changes in damping
and stiffness properties of viscoelastic polymer matrix composites using the temperature rise of a cyclic loaded specimen.
It is demonstrated that for a ceramic matrix composite, where interfacial frictional sliding gives rise to heat dissipation,
the temperature resolution can be used for detection of stress-strain hysteresis with an accuracy better than that of the
stress-strain data. 相似文献