Crespo Vázquez, DanielAlonso Fernández, JoséBernabeu Martínez, Eusebio2023-06-202023-06-202000-08-011559-128X10.1364/AO.39.003805https://hdl.handle.net/20.500.14352/59235© Optical Society of America. This research was supported by a project from the Comisión Interministerial de Ciencia y Tecnología (CICYT) under grant TAP 98-0862.Reflection optical encoders are studied as three-grating moiré systems. An analysis is made of the differences that may appear between it and the standard case in which an optical encoder is regarded as a two-grating system.engjournal articlehttp://dx.doi.org/10.1364/AO.39.003805http://www.opticsinfobase.orgopen access535DiffractionÓptica (Física)2209.19 Óptica Física