History of Filters
For more than 100 years, photographers have used filters to reduce reflections, balance color and enhance the contrast in black-and-white photos. In hopes of achieving similar results, integrators across the world have attempted to use photographic filters in industrial vision systems. Some improvements can be seen with these filter types; however, they’re specifically designed for film cameras, and the spectral response (sensitivity) of film is from 400 to 700 nm, also known as the visible spectrum.
Digital cameras used in machine vision systems are unable to function at an advanced level with photographic filters because they have charge-coupled device (CCD) and complimentary metal oxide semiconductor (CMOS) sensors, which are sensitive to the ultraviolet, visible and near-infrared portion of the spectrum. In order to take control of lighting conditions and image quality, filters that perform well over the entire sensitivity range are required. We offer a variety of options and can help you determine which filter is best for your vision system.