Colour measurement head for anodized aluminium - has transparent contact disc placed on wetted sample surface and photocell measuring reflectance

摘要

The head for measuring whiteness, blackness or colour tone of a sample, e.g. of anodized aluminium, comprises a light source, a light guide and a photocell to measure the reflectance outside the reflection angle of the light from the source reflected by the sample. In the beam path between the source and the sample there is a transparent contact disc. The disc is placed on the wetted surface of the sample. The contact disc is pref. made of glass and the actual contact surface of the disc is pref. raised above its mounting in the measuring head.