Abstract
Image intensifier plays an important role in the field of weak signal detection as well as microlight night vision imaging, and dynamic range is one of the key indexes to determine its performance. To thoroughly analyze and study the dynamic range width of the image intensifier, a wide dynamic range test system has been designed, centered around a camera equipped with fiber optic plates. The system produces uniform illumination at varying levels using a semiconductor laser, and employs an FPGA chip for logic control to drive the fiber-coupled GSENSE400BM image sensor. It captures the brightness of the fluorescent screen of the image intensifier under different lighting conditions, transmits the data via the USB 3.0 interface, and utilizes custom upper computer software to analyze the grayscale of the images. In the experiment, the dynamic range of the image intensifier was tested by changing the illumination from 0.125 Minimum Ionizing Particle (MIP) to 105 MIP, and the upper computer performed the analysis of the image's grayscale statistics to get the linear curve of Gray-MIP value, and finally, the area with nonlinearity over 30% was set as the nonlinear area to get the final dynamic range curve. The experimental results demonstrate that the developed dynamic range test system, based on the fiber-coupled camera, features a wide dynamic range and minimal data transmission loss, making it suitable for the wide dynamic range testing of image intensifiers.