Color
Color is a sensory impression mediated by the eye and brain, which is caused by light with a wavelength between 380 and 780 nm.
Visible spectrum
In image processing, the use of different illumination colors creates contrasts with which an inspection task can be solved better or more efficiently. A color camera, for example, is not always required. This allows certain colors to be highlighted or suppressed in monochrome imaging with colored lighting. If, for example, blue light hits multi-colored surfaces such as pens, the blue surfaces reflect the light most strongly, while the others absorb it depending on the color.
Colored pens (source: Baumer), illuminated with different colored lights. The grayscale images show the result:
The blue pencil (second from the right) appears very bright and areas with a red component appear extremely dark. This can create contrasts that can be decisive for a successful application solution.
White color -> Color temperature
