Device for angle of rotation determination

摘要

In a device for determining the angle of rotation of a rotating member by use of a perforated disk which corotates with the rotating member and intermittently interrupts a continuous beam of light directed at the perforations of the disk, an improvement comprises providing perforations of the disk which define light permeable and light impermeable areas such that a width of the light permeable areas is less than a width of the light impermeable areas, and a width of the light permeable areas is approximately the same as a width of an aperture at a light receiving station. A symmetrical output signal is obtainable so as to increase a resolution of the angle of rotation measurement.