Patent ID: 8525459

Claim:
An optical encoder, comprising: a light source; a light sensor array; and a code disk including: a data track having a plurality of slots configured to allow light from the light source to pass to the light sensor array to determine a rotational position and direction of the code disk; and a commutation pattern having: a first commutation track including a series of apertures which are spaced closely enough together to allow light to continuously pass from the light source to a first light sensor of the light sensor array such that the first light sensor continuously receives light as the series of apertures passes over the first light sensor; a second commutation track including a series of apertures which are spaced closely enough together to allow light to continuously pass from the light source to a second light sensor of the light sensor array such that the second light sensor continuously receives light as the series of apertures passes over the second light sensor; and a third commutation track including a series of apertures which are spaced closely enough together to allow light to continuously pass from the light source to a third light sensor of the light sensor array such that the third light sensor continuously receives light as the series of apertures passes over the third light sensor; wherein the relative positions of the first, second, and third commutation tracks correspond to a continuous commutation sequence of a first coil, a second coil, and a third coil of a brushless motor.