非制冷红外焦平面阵列器件的热时间常数测试方法

热时间常数是基于微测辐射热计的非制冷红外探测器的关键指标参数，它与探测器的最高有效帧频直接相关，因此准确测量热时间常数对于器件设计和应用都有举足轻重的意义。但目前无论是探测器热时间常数的标称值还是基于单元的热时间常数现有方法的测试值，都无法建立与探测器的频率响应特性的直接定量函数关系，以确定探测器工作的最小帧间时间间隔。直接基于阵列器件测量热时间常数的方法，借助低于1/2帧频的斩波调制，通过变频时域采集，快速傅里叶变换（FFT）等常规测试手段，提取有效的电压响应信号，拟合频响曲线，能快速有效地提取热时间常数。通过实测分析，该测量方法具有准确度高、抗干扰能力强、稳定性高、测试用时短的特点，且均采用通用的测试仪器，无需单独制作测试样品，具有较高的推广价值。

A test method of thermal time constant for uncooled infrared focal plane array

The thermal time constant is a key indicator of the uncooled infrared detector based on the microbolometer, it is highly related to the effective frame rate of the detector. Therefore, it is necessary to measure thermal time constant for device design and application. However, the typical design value or the measurement result based on mono-element is not easy to establish the quantitative relationship with the frequency-response characteristic of the detector. In this paper, a method for measuring thermal time constant based on array devices was introduced. The method employed a chopper to obtain a chopping frequency that was less than 1/2 frame rate, after the fast Fourier transform calculation, fitting the frequency response curve by the effective voltage response signals at different frequency point, the thermal time constant could be quickly and effectively extracted. By the experiment proving and results analyzing, the method has the advantages of high precision accuracy, strong anti-interference ability, good stability and short test time. What's more, there is no special requirement for testing instruments or testing samples, and is worthy to be popularized.