超高速分幅相机中的无鬼像光学系统

超高速光电摄影系统是目前最常用的一种高速摄影设备。在进行超高速光电分幅相机光学系统的设计时,由于面数较多、结构较为复杂,很容易在像面附近形成鬼像,从而影响成像的锐度和对比度,干扰目标的识别。为了解决鬼像的问题,本研究从光学系统中的关键器件像增强器出发,分析了鬼像形成原因,并进一步采用光纤面板对像增强器进行了优化设计,从而克服了鬼像问题。采用本光学系统组成的超高速光电分幅相机拍摄了高压火花放电的过程,实验结果表明,得到的图像无鬼像。利用该系统可以方便地进行纳秒时间尺度的超高速摄影实验研究,拍摄的照片无鬼像,有利于目标的精确识别和解读。

Research on optical system without ghost images for an ultra-high-speed framing camera

Ultra-high-speed optical camera systems are a common type of high-speed photography equipments. When the optical system of ultra-high-speed photoelectric framing cameras is designed,the a ghost image is formed in the vicinity of the image plane due to the large number of surfaces and complex structure,which can affect the sharpness and contrast of the images and influence the target recognition. In order to slove the problem of ghost images,the cause of ghost images was analyzed,and a fiber optic panel was used to further optimize the design of the image intensifier. In a further experiment,a high-voltage spark discharge was captured by an ultra high-speed photoelectric framing camera with this optimized optical system. The results demonstrate that the obtained image has no ghost image. This system can be used in ultra-high speed photography experiments with nanosecond time scale because the obtained photographs have no ghost images,which is favourable for the accurate identification and interpretation of targets.