用于10μm微测辐射热计的红外光学天线设计

Design of Infrared Antenna for 10μm Micro-bolometer

微测辐射热计利用热敏电阻对温度的敏感特性来实现红外探测,将光学天线场局域的能力应用于微测辐射热计,可以集中入射能量至热敏电阻,提高电阻的温度响应。基于这一思想设计了一种工作在红外波段的改进型蝶形光学天线,其中心场强最高可增强83倍。采用了多物理分析方法,结合两种常用的热敏材料(铝和氧化钒)对耦合结构的电磁特性和热学特性进行了分析。结果显示,在1000 W/m^2的入射功率密度下,铝温升可达1.85 mK,氧化钒温升0.85 mK,与同类工作相比温度响应增强了数倍。该改进型蝶形光学天线可用于微测辐射热计提升红外探测效率,在高密度红外成像器件应用中发挥作用。

Micro-bolometers make use of the sensitivity of thermistor to temperature to realize infrared detection. By combining field enhancement of optical antenna with micro-bolometer, the incident energy can focus on thermistor and the temperature response of the thermistor will be improved. Based on this idea, we design an improved bow-tie antenna working in the infrared band, which can enhance the electric field by 83 times. A multi-physics simulation is used to analyze the antenna with two kinds of thermistor(aluminum and vanadium oxide). The results show that at an incident power density of 1000 W/m^2, the temperature rise of Al is 1.85 mK and the temperature rise of VOx is 0.85 mK. The temperature response is several times of other similar work. The improved bow-tie antenna can be used on micro-bolometer to increase the detection efficiency and play a role in high density imaging device applications.