Sensor for the detection of local contrast gloss of products.
We introduce a sensor for providing information on the local contrast gloss (or luster) of products. The sensor also provides information of the local specular gloss of the object. The signals of this sensor are produced by diffractive optical elements from fields that are scattered in the diffuse and specular directions from the object. We present specular gloss, diffuse-reflectance factor related to the contrast gloss, and visibility maps measured from black prints on paper. High variation can be observed in the relevant gloss parameters obtained from the printed area. In addition, borders of the print can be clearly detected from the diffuse-reflectance-factor maps. The sensor also allows detection of raster points of a print. This sensor opens up entirely new means to study prints and other substances.
Oksman
Antti
A
Department of Physics and Mathematics, University of Joensuu, Joensuu, Finland. antti.oksman@joensuu.fi
Juuti
Mikko
M
Peiponen
Kai-Erik
KE