METHOD FOR MEASURING PLATE-OUT AND POLYMER-MOLDING PROCESSING APPARATUS ACCOMPANYING FUNCTION OF THE MEASUREMENT

PROBLEM TO BE SOLVED: To quickly measure a plate-out of a metallic surface in a noncontact manner by projecting light to the metallic surface of a metallic roll or metallic press sheet for molding of a polymer material and obtaining a reflectance of a returning light. SOLUTION: A light source 10 can be, e.g. a mercury lamp, a halogen lamp, a fluorescent lamp or the like. From a view point of measurement accuracy, a short wavelength laser, an excimer laser or the like which sends light with superior linearity is preferred. A photodetector 11 is, for instance, a photodiode, a photomultiplier, an optical counter or the like, measuring an intensity of a returning light. The intensity of the returning light is divided by an intensity of an incident light from the light source 10, thereby obtaining a reflectance. A plate out of a metallic surface is measured in this manner. An angle of incidence of the light is set to be 0-90 deg.. The angle is set to be large when the plate out is small, while the angle is reduced when the plate out is considerably large, thereby correcting the reflectance with the angle of incidence. A thickness of the plate-out can also be measured from the reflectance.