Phoenix Contact Gmbh + Co. Kg

Mazet Gmbh

Fred Grunert

Gunter Siess

Thomas Nimz

Frank Krumbein

Fredrik Hailer

An apparatus for illuminating the surface of a material, comprising an illuminating device for illuminating the surface of the material with a calibrating light, a recording device for recording a measuring light, emitted by the surface of the material in response to the calibrating light, and a processor device for recording the spectral characteristic of the measuring light that characterizes a diffuse spectral reflectance of the surface of the material, wherein the illuminating device is configured to generate an illuminating light for illuminating the surface of the material that has a spectral characteristic that corresponds to the spectral characteristic of the measuring light.

Apparatus for illuminating the surface of a material

The invention is directed to a photosensor for color measurement based on three spectral components, particularly for highly accurate color measurement for testing and guaranteeing color constancy in engineered surfaces and consumer articles of any kind. The object of the invention, to find a novel possibility for color measurement based on a three-range method with color measurement values generated by preceding interference filters with different spectral responses which permits a virtually true-color measurement in conformity with standards in a simple manner without costly reference light calibration, is met according to the invention in that the photosensor comprises at least three partial surfaces which are covered by different interference filters adapted to the X-, Y- and Z-spectral characteristic of the human eye, each partial surface being arranged so as to be uniformly distributed in a sector-shaped manner and so as to cover the same area around a center with passivated webs located therebetween, and every partial surface is provided with an interference filter whose transmission characteristic over the wavelength of the light to be measured spectrally is adapted to the response of the human eye, wherein the spectral components passed by the interference filters approximate the normal spectral value functions of the human eye in color coordinates of the color space.

Growing community of inventors

Bad Klosterlausnitz, Germany

Fred Grunert