APPARATUS FOR MEASUREMENT OF SURFACE PROFILE AND CONTROL METHOD THEREOF

摘要

An apparatus for measuring surface profile and a control method thereof are provided to extend an exchange period of a light source and reduce the whole measurement time by allowing more than two photographing units to photograph interference light alternately. In an apparatus for measurement of a surface profile, a light source(10) emits light. A first light dividing unit(50a) makes the light of the light source face an object(1). A light interference module(20) irradiates light to the object by the light of the first light dividing unit, and forms interference light on the basis of the light reflected by the object. A first photographing unit(40a) photographs the interference light emitted from the light interference module. At least one second photographing unit(40b) photographs the interference light emitted from the light interference module. A second light dividing unit(50b) divides the interference light emitted from the light interference module and passing through the first light dividing unit to face the first and second photographing units. A transporting unit(30) adjusts a gap between the light interference module and the object. A control unit(60a) receives information about the gap from the transporting unit, makes the first and second photographing units alternately photograph the interference light under a condition of synchronizing an alternate photographing timing of the first and second photographing units with an on timing of the light source on the basis of the information about the gap between the light interference module and the object.