Uncooled Optically Readable Bimaterial Micro-Cantilever Infrared Imaging Device

We develop an uncooled infrared imaging device that contains a SiN-Au bimaterial micro-cantilever arrays detector and an optical read-out section. The detector converts the incident infrared radiation to the cantilever inclination angles, and the optical read-out section converts these angles directly to a visible image through an optical filtering operation to the spectra of the cantilever arrays with a knife-edge filter. The present results with the 140 x 98 cantilever arrays and the 8-bit A/D quantizer suggest that the objects at the temperature of 250°C at the distance as far as 1m can be detected and the noise-equivalent temperature difference (NETD) of the device is about 10 K. The further improvement of NETD is expected to approach about 14 mK with the optimized cantilever design and 12-bit quantizer.