红外技术2012，Vol.34Issue(7)：422-426,5.
多碱光电阴极膜厚对阴极灵敏度的影响研究
Study on Sensitivity of Different Thickness of Multi-Alkali Photocathode
摘要
Abstract
This paper described the spectral reflectance characteristic of multi-alkali photocathode, measured the spectral reflectance curve of multi-alkali photocathode on the second generation image intensifier, analyzed the reason of both interference peak and valley on spectral response curves, and compared the difference of spectral reflectance curve between different photocathode film thicknesses. According to the law of conservation of energy, the spectral absorption curve of multi-alkali photocathode is calculated by the spectral reflectance and transmittance measured on multi-alkali photocathode. Through the research of different thickness cathode absorption spectrum, the characteristic that the film thickness of multi-alkali photocathode does not improve light absorption of all wave bands was found. Thickness increases will only increase the short wavelength and long wavelength optical absorption rate, but the middle wavelength band light absorption rate does not increase but declined. This is due to the influence of spectral reflectance. Cathodes film thickness affects both the spectral reflectance and the spectral transmission, and then affects the absorption spectrum, thus also affect spectral response of multi-alkali photocathode. So the film thickness of multi-alkali photocathode is the key parameter for sensitivity. Experiments proved that the thickness of multi-alkali photocathode produced by transfer technology has an optimum value, exceeding the optimum thickness, the cathode sensitivity falling instead of rising. The reason is that the IR spectral response increases not much, but the short wavelength spectral response decreased a lot. So for multi-alkali photocathode produced by the transfer technology, practice has proved that the cathode film will take the color of pale red when the optimal film thickness is got. In the production process of multi-alkali photocathode to obtain higher cathode sensitivity, it is a key to control the cathode film thickness.关键词
多碱阴极/光电发射/Na2KSb膜层/光谱特性/膜层厚度/阴极灵敏度Key words
Multi alkali photocathode. Photoemission/ Na2KSb film/ Spectral characteristic/ Film thickness/ Cathode sensitivity分类
数理科学引用本文复制引用
李晓峰,李莉,杨文波,邱永生..多碱光电阴极膜厚对阴极灵敏度的影响研究[J].红外技术,2012,34(7):422-426,5.基金项目
微光夜视技术国防科技重点实验室基金,编号:J2011016. （）
