A 0.25µm logarithmic CMOS imager for emissivity-compensated thermography

Challenges in the design of solid-state imagers for industrial measurement and control include: high image resolution, wide temperature range, adequate temperature resolution, high measurement speed, thermal stability of the sensor chip, and most importantly, low cost. However, they have the inherent disadvantage that their temperature information is strongly dependent on the emissivity of the probed material. This shortcoming can be eliminated if the ratio of an unfiltered and a filtered response of two photodiodes is considered.