AO000659

An inexpensive means of optimizing image information is the use of optical filters. The basic idea in most cases is to increase contrast in the resulting image. This can be achieved, for example, by suppressing interfering wavelength regions in the light spectrum, so that colored features can be brightened or darkened, as when using colored illumination. Disturbing extraneous light influences can be avoided or simply the wavelengths of the light used can be limited to such an extent that the camera sensor operates at its optimum.