Development of a Plate Flatness Meter Based on Laser Moiré Method

Abstract

A plate flatness meter based on the laser moiré method has been developed. A large grating is installed above a plate transfer line, a laser beam is directed through a concave lens onto the plate on the transfer line. Moiré fringes that conform to the surface profile of the plate are formed on the plate. The flatness of the plate as it is transferred can be measured to a high accuracy of ±1.0mm(2σ).