A method of improving the resolution and accuracy of rotary encoders using code compensation technique

Abstract

A method for improving the resolution and accuracy of incremental type rotary encoders using a phase encoding and code compensation system is described. Applying this system to an optical incremental encoder whose scale pitch is 1/36000, a rotation resolution of 1/920000 and a better than +or-1/300000 rotation (+or-0.0012 degrees ) precision are obtained. The system can also be used for a precise measurement of speed fluctuation.<>