OPTICAL SCALE, METHOD FOR PRODUCING OPTICAL SCALES, AND OPTICAL ENCODER

摘要

Provided are an optical scale, a method for producing optical scales, and an optical encoder which enable resolution to be increased and the effects of fluctuations in amounts of light that are detected to be reduced. The optical scale transmits or reflects light from a light source, and has a plurality of fine metal wires positioned in such a manner that the tangential directions change continuously without intersecting. The optical encoder includes an optical sensor that includes: said optical scale; a light source; a first polarizing layer that separates incident light from the light source that enters after being transmitted or reflected by the optical scale in a first polarization direction; a second polarizing layer that separates the incident light in a second polarization direction; an optical sensor that contains a first light receiving part that receives first separated light separated by the first polarizing layer; and a second light receiving part that receives second separated light separated by the second polarizing layer; and a computation means that computes the relative amount of movement between the optical scale and the optical sensor, from the intensity of the first separated light and the intensity of the second separated light.