Optical displacement encoder

摘要

An optical encoder includes a scale having bar-like scale marks; a detection head having a light source fiber emitting coherent light at the scale and a photoreceiver fiber receiving light reflected off the scale; electronic components connected to the detection head via the light source fiber and the photoreceiver fiber; and a protector covering the scale marks at a predetermined distance from the scale marks. The protector is a member configured with light-transmissive material and includes a top surface that is inclined with respect to a principal surface of the scale.