System and method for angular measurement

摘要

Embodiments of the present invention include a method for measuring an angle between a first surface and a second surface of an object. The method includes rotating an object around a center axis of the object and shining a light source perpendicular to the center axis of the object. The method further includes measuring an intensity of a reflected light with respect to time and determining an angle between two or more surfaces of the object based on the intensity of the reflected light with respect to time.