Wavefront coding-based athermalized infrared pixel super-resolution imaging technology

The infrared imaging system is bound by insufficient sampling frequency, which cannot detect high-frequency detail. Moreover, when the ambient temperature changes significantly, thermal defocusing may occur, leading to further degradation of image quality. Most existing technologies only improve the resolution of infrared imaging systems or solve the problem of infrared thermal defocusing imaging. We propose infrared imaging of athermalization, a super-resolution technology based on wavefront coding, which will utilize this classic computational imaging technique to achieve the all-time focus of infrared imaging systems and improve their resolution. We put a specially designed phase mask plate at the aperture plane of the infrared lens, rotate the phase mask plate at different thermal defocus distances to capture the target scene multiple times, and combine iterative reconstruction to obtain in-focus high-resolution infrared images. The experiment shows that this technology can achieve imaging without defocusing within the temperature range of -20 °C to 60 °C, and improve image resolution by 2 times, achieving high signal-to-noise ratio imaging.