A full absolute encoder realized with a high-resolution optical angle sensor and a revolution counter using a magnetic bubble device

Detailed construction of a full absolute encoder consisting of an absolute angle sensor using a diffused light optical system and a revolution counter using magnetic bubble device was discussed. Using this optical system, a high resolution (1/20²⁰ of revolution) compact angle sensor was realized. Real time data output was also realized by using a digital signal processor. The feature of backup battery free revolution counting was brought out using precision compact magnetic circuits and electrical circuits.