Abstract: An optical encoder for producing adjustable quadrature phased signals by positioning of a light-controlling member includes a light emitter including a non-collimated, point-source light emitting diode for emitting light and a light receiver that receives light from the light emitter. A light-controlling member is disposed between the light emitter and the light receiver and includes a plurality of transparent portions for passing light from the light emitter and a plurality of non-transparent portions disposed alternately with the transparent portions for blocking light from the light emitter. The light emitter and the light-controlling member are moveable relative to each other.