Development of Micro-magnetic Scale with Electroplating of Magnetism

A magnetic encoder is an element that detects the moved distance, speed, and rotation angle by sensing magnetism. This has been detected by reading the scale of the magnetic pattern with magnetic sensors. Therefore, it is possible to use these in severe situations such as in liquid and under dust. The magnetic scale of a magnetic encoder is obtained by machining a magnetic substance or by injection molding a plastic magnet. However, it is difficult to obtain the pitch on a detailed scale in the machining. Moreover, a plastic magnet is vulnerable to radiation. We aimed to develop a magnetic scale that was resistant to high temperature and radiation. We combined photolithography and electroplating to form an under 200-micro-meter micro-indentation pattern for the magnetic substance metal and used it as a scale.