Optical EngineeringDetermination of the central position of rotation of a rotating object by laser Doppler velocimetry
|Format||Member Price||Non-Member Price|
New methods to determine the central position of rotation of a rotating object using laser Doppler velocimetry (LDV) are described. The principle is based on the fact that the tangential velocity of the rotating object is proportional to the distance from the center of rotation and that it can be measured by LDV with a microscope optical system. To realize this principle, three methods (angular and tangential velocity method, multiple-point method, and two-point method) are proposed. In the third method, a holographic optical element was used to play the role of multiple beamsplitter and a lens to obtain a rigid and simple optical system. From experimental results, it has been indicated that the position of the center of rotation is determined with an accuracy of 1 to 2 μm by these methods.