Patent ID: 7355165

Claim:
An optical encoder comprising: a housing having an interior wherein the interior is defined between a top end and a bottom end; a shaft extending outward with respect to the housing to a point exterior to the housing; a circuit board connected to the housing; a light emitting element connected to the circuit board wherein the light emitting element transmits an amount of light; a light detector connected to the circuit board wherein the light detector detects the amount of light; and a light pipe positioned between the light detector and the light emitting element wherein the light pipe deflects light from the light emitting element to the light detector wherein the light pipe has a first end, a middle portion and a second end wherein the first end of the light pipe and the second end of the light pipe are located further from the top end of the housing than the middle portion of the light pipe a sprocket connected to the shaft wherein the sprocket produces a sound via rotation of the shaft.