COUNTER-ROTATING SCANNER

摘要

A scanner and a method for scanning a beam along a path employ a housing (320) that defines a first cylindrical cavity (322). A ring gear (330) is disposed within the cylindrical cavity and affixed to the housing. A beam (312) is generated from a fixed location relative to the housing. A drive disk (340) is disposed within the first cylindrical cavity. The drive disk defines a second cylindrical cavity (348) and has a first axis of rotation (315). The drive disk defines a first channel in communication with the beam. The first channel (346) has a first proximal end pivotally rotatable about an axis adjacent the fixed location. A scan disk is disposed within the second cylindrical cavity and has a second axis of rotation offset from the first axis of rotation. The scan disk defines a second channel (366). The second channel has a second proximal end (374) in communication with the first distal opening (354). A spur gear (332), affixed to the scan disk, engages the ring so that the drive disk rotates in the first direction, the spur gear is displaced along the ring gear (330), thus causing the scan disk to rotate in a second direction opposite the first direction causing the second distal end to reciprocate. The beam is coupled through the first channel and the second channel and out of the second distal opening toward the path, thereby causing the beam to scan along the path as the second distal end reciprocates.