微机械光读出红外成像阵列器件机械特性对其性能的影响

Effect of mechanical characteristic of an micro-mechanical optically readable infrared imaging array device on its performance

研究了具有“双材料梁-微镜一体化”特征结构的光读出红外成像阵列器件的机械特性对其性能的影响。通过理论计算和ANSYS模拟,分析了器件的热-机械灵敏度,对器件的结构参数进行了优化,并得到其热-机械灵敏度为2.14×10-3rad/K;从器件的频率和阻尼特性出发,研究了器件的机械特性对热振动噪声和机械稳定性能的影响。研究结果表明:绝热梁断裂所需冲击载荷为8 945 g;器件的工作气压确定在50-200 Pa时,其热机械噪声和外界机械振动引起的噪声对器件性能的影响可忽略。该器件基本满足红外成像阵列器件的高灵敏度、低噪声的要求。

For an optically readable infrared imaging array device with a bi-material beam micro-mirror integrated structure, the effect of mechanical characteristic of the pixel on its performance was studied. Thermal-mechanical sensitivity was analyzed by theoretic calculation and ANSYS simulation to optimize the geometric parameter and the thermal-mechanical sensitivity of 2.14 × 10^-3 rad/K was ob- tained. Based on the study of frequency and damping, the effects of mechanical characteristic on thermal vibration noise and mechanical stability were analyzed. The results show that the mechanical impulse inducing fracture is 8 945 g,and when the working pressure is determined to be 50-200 Pa, the thermal vibration noise and noise induced by ambient mechanical vibration can be neglected. The results satisfy the requirement for infrared imaging device in high sensitivity and low noise.