共查询到17条相似文献,搜索用时 171 毫秒
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像增强器的多信息量测试技术研究 总被引:1,自引:1,他引:0
阐述了像增强器的单色光反射率,光谱响应曲线,单色光电流的测试原理,介绍了多碱电阴极多信息量测试系统,该系统可在像增强器制备过程中在线测试其阴极的单色光反射率,光谱响应曲线,单色光电流等参量,本文还给出了并分析了在该系统应用于一代像增强器制备过程中的测试结果。 相似文献
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《红外技术》2018,(2):189-192
为了探究Cs、O激活电流对透射式GaAsP光阴极光谱响应特性的影响,通过光谱响应测试仪测试不同Cs、O电流激活后的透射式GaAsP光阴极光谱响应曲线,结果表明,随着铯氧蒸发电流比的减小,GaAsP光阴极光谱曲线的形状会发生一定的改变,长波响应能力逐渐降低、短波响应能力逐渐提高。利用双偶极层模型理论,分析认为铯氧蒸发电流比的改变影响了GaAsP光阴极表面势垒的形状,使得不同激发能量的光电子通过隧道效应穿越表面势垒宽度发生变化,从而影响GaAsP光阴极光谱响应特性。根据此现象对进一步提高GaAsP光阴极在530 nm特征波长的量子效率具有积极的意义。 相似文献
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利用自行研制的光电阴极激活评估实验系统,对激活后的反射式GaN及GaAs光电阴极进行了稳定性测试,获得了Cs/O激活一段时间后阴极随时间变化的光谱响应,通过计算得到量子效率曲线.结果表明:激活结束后GaN灵敏度可以在较长时间内保持稳定,而后缓慢衰减.而GaAs光电阴极的光电流随时间近似呈指数衰减.结合阴极表面双偶极层结构以及表面化学成分,分析原因主要是:两种阴极表面进行Cs/O激活后形成的双偶极子的结构不同、衰减过程中双偶极层化学成分变化方式不同决定.GaN光电阴极激活后cs以复杂氧化物存在,更加稳定,灵敏度的衰减主要是由未分解的氧引起,而GaAs灵敏度下降的原因主要是表面双偶极层中的Cs极易脱附,影响其稳定性. 相似文献
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Recent advances in materials technology, activation technology, and device technology have brought to fruition practical imaging
devices utilizing NEA photoemitters. This paper describes the characteristics of proximity-focused image tubes utilizing large-area
semitransparent, single-crystal III-V photocathode structures. Since the spectral response of the photocathode is determined
by choice of the material used as the photoemitting layer, specific choices allow optimization for specific applications;
e.g., laser illuminators. The material selection criteria and methods of fabricating the photocathode material structure will
be discussed.
The use of NEA materials allows the separation of the bulk photocathode material from other tube processing variables and
has allowed a high degree of reproducibility from device to device. Specific device characteristics to be included in this
discussion are resolution, stability of the photocathode during operation, and photocathode spectral data. 相似文献
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为了准确测量光电成像系统的绝对光谱响应效率,采用光学系统光能量传递公式以及图像传感器的物理模型,得到了光电成像系统绝对光谱响应效率的计算公式,在此基础上设计了基于积分球、多光谱发光二极管光源、标准探测器及透射式平行光管的光电成像系统绝对光谱响应效率测量装置,并对光谱响应效率已知的可见光数字相机进行实验测量和分析。结果表明,在380nm~1100nm波长范围内测量装置测得的可见光数字相机的绝对光谱响应效率与标准值具有较好的一致性,最大相对误差为1.7%,各波长点的测量不确定度在置信概率为95%时均小于0.2%,满足一般的测量要求。该装置能够准确地对光电成像系统的绝对光谱效应效率进行测量。 相似文献
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研制了基于电子束时间展宽技术和微通道板(microchannel plate,MCP)选通技术的时间展宽分幅相机。相机有三条厚度80 nm、宽度8 mm的微带阴极,阴极上加载斜率为2.1 V/ps的高压斜坡脉冲,使得先发射的电子较后面的电子速度快,经过50 cm的漂移区后,电子束产生时间展宽,从而提高相机时间分辨率。阴极和MCP均加载了脉冲电压,因此,需要精确同步光脉冲、阴极脉冲和MCP选通脉冲,分析了完整的同步过程。当阴极仅加直流电压,无电子束时间展宽时,获得相机的时间分辨率为78 ps。当阴极加载高压斜坡脉冲时,电子束时间展宽技术将系统的时间分辨率提高至12 ps。改变延时,将光脉冲分别同步在斜坡脉冲不同位置,获得了时间分辨率与同步位置的关系。 相似文献
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We have observed electron emission into vacuum from the exposed areas of a patterned p++-GaAs substrate which was coated with cesium and oxygen. The emission barrier is a double layer of titanium-tungsten/silicon nitride. The exposed areas of the cathode were activated to the negative electron affinity (NEA) condition. It has been an open question whether it would be possible to activate the exposed areas of a patterned GaAs cathode. This result opens the possibility of utilizing NEA cathode technology for projection electron beam lithography tools, NEA-based vacuum microelectronics devices, and a combination of bulk devices with NEA emitters. A picture of an emission pattern projected onto a phosphor screen is presented. Auger depth profile was used to determine the stability of the TiW/GaAs interface through the activation procedure. Short and long term current stability were measured. A technique for cathode recovery and reactivation has been developed 相似文献
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《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》1974,62(10):1339-1360
Semiconductors with negative electron affinity (NEA) surfaces are used as photoemitters, secondary emitters, and cold-cathode emitters. A comprehensive review of the characteristics and applications of these materials is presented, the concept of NEA is described, and a comparison is made between NEA and conventional emitters. Electron generation, transport, and emission processes of NEA emitters are discussed. NEA III-V compound photocathodes, especially GaAs, are described with respect to their fabrication, performance, and applications to photomultipliers and image intensifier tubes. The structure and performance of NEA secondary emitters are presented. NEA GaP secondary-emission dynodes represent the most important device application. NEA cold cathodes, using GaAs, Ga(As, P), or Si, have been investigated, and their performance characteristics are summarized. NEA Si cold cathodes have been incorporated in developmental TV camera tubes. The characteristics of these tubes are reviewed. 相似文献