Patent ID: 7763843
Filing Date: 2010-07-27
Classification: G10H

Abstract:
1. A controller comprising: a rotatable platter journaled for rotation, said rotatable platter including a top surface and a side circumferential skirt substantially perpendicular to said top surface, said circumferential skirt includes a random pattern; said rotatable platter disposed for direct user manipulation and rotation; a relative displacement detecting optical system comprising a lens, an image sensor, a light source and a signal processor responsive to relative movement of said rotatable platter based on information derived from said random pattern; said optical system being positioned to optically acquire surface sequential images from said random pattern of said side circumferential skirt and calculate differences in said sequential surface images of said random pattern thereby determining the direction and relative displacement of rotation of said rotatable platter; and said optical system including an output responsive to said rotatable platter.