新型单帘航摄焦平面快门

快门是控制感光介质曝光量的重要组件,为使航摄快门适应面阵CCD相机对空间结构上的要求,同时做到幅面曝光时间均匀、曝光时间调节范围大、并且曝光时间连续可调,设计了新型帘幕式快门。在分析了快门的曝光原理的基础上推导出快门有效曝光时间计算公式,并结合快门的有效曝光时间计算公式设计了单帘式快门,采用帘幕环绕面阵CCD的快门结构形式,快门帘幕采用四辊轴的结构形式,并利用正时带实现了快门的曝光功能,利用高斯误差合成对快门系统的精度进行了分析计算,得到系统的曝光精度为0.057。实验结果显示,快门能够实现1/50~1/250 s的曝光时间调节范围,通过光电法实验测得快门的曝光精度达到0.056,满足0.1的曝光精度指标要求。

New single curtain type shutter used on aerial camera

Shutter is a chief module which controls the exposure of the photosensitive material.To adapt the space and structure of the array CCD aerial camera while making sure the exposure time is uniform in breadth with wide adjustable range and continuous adjustment,a new curtain type shutter was designed.Based on the analysis of shutter exposure principle,the expression of effect exposure time was worked out,and the single curtain type shutter was designed associated with the expression of effect exposure time.The curtain-surround area CCD was adopted on shutter structural style,and the four roll shaft surrounding curtain was adopted.Exposure in shutter came true with the primary use of timing belt.The precision of exposure was analyzed and calculated by Gaussian processes,which was 0.057.The result of experiment shows that the exposure time of the shutter could be in the range of 1/50-1/250 s.The exposure accuracy can reach to 0.056 with the index of 0.1 according to the photoelectric experiment.