Patent ID: 6133706
Filing Date: 2000-10-17
Classification: B41J

Abstract:
Apparatus for home-positioning a movable subsystem relative to a fixed frame of reference within a printer, the apparatus comprising:an encoding pattern arrayed linearly along one of a movable subsystem and a fixed frame of reference within a printer, said pattern including a regular pattern of alternately optically reflective and optically non-reflective stripes, one of said stripes defining a distinctive homing patch that is distinguishable from all remaining stripes;an optical source mounted on the other of the movable subsystem and the fixed frame of reference, said optical source illuminating said encoding pattern;an optical multiple-sensor array adjacent said optical source and mounted also on the other of the movable subsystem and the fixed frame of reference, said array detecting luminance modulation resulting from illumination of said encoding pattern by said optical source; anda controller operatively coupled with said array for decoding such detected luminance modulation to sense the presence of said homing patch within said encoding pattern.