红外成像系统噪声等效温差数字图像测试方法

摘要

The Noise Equivalent Temperature Difference ( NETD ) is one of the key function parameters for infrared imaging system evaluation,and digital images are finding wider application in displaying and recording of infrared imaging systems .But almost all the existing NETD test methods are based on analog images.We proposed a method for testing NETD based on digital images .The Least Squares were used to fit the signal transfer function,and a 3-D noise model was used for analysis and calculation of the IR system noise .A method for calculating NETD was presented .With the test environment constituted,tests were made for the NETD of linear scanning and focal plane array IR imaging system .The test data obtained were also analyzed .%噪声等效温差是评价红外成像系统性能的关键参数之一。数字图像在红外成像系统的显示与记录中得到越来越广泛的应用，但原有的噪声等效温差均是基于模拟图像进行测试。提出基于数字图像的红外成像系统噪声等效温差测试方法，用最小二乘法拟合信号传递函数，用三维噪声模型分析并计算系统噪声，给出了噪声等效温差的计算方法。搭建测试环境，分别对线列扫描红外成像系统和焦平面阵列红外成像系统进行测试，并对测试数据与标称值进行对比、分析。