Investigations on infrared-channel-image quality improvements for multispectral imaging

The improvement of image quality in the infrared range on silicon-based sensors is one major topics using these long wavelength channels for geometric measurements. The reason behind the bad quality of infrared images in comparison with the visible sampling range is explained by the wavelength response dependency of the silicon. Photons are able to either to pass the sensitive range of the pixel or can tunnel to the neighbor pixel. This effect leads to blurred images, which will not only increase the uncertainty of measurement, but also the aesthetical quality of the image. In this paper, methods to improve the image quality using blind convolution as well as a special infrared focusing to improve the sharpness will be presented. (paper)