Patent ID: 6844891
Filing Date: 2005-01-18
Classification: B41J,H01L

Abstract:
1. A method of aligning in five degrees of freedom a multichannel laser printhead to be used in thermal transfer of material from a donor to a substrate, comprising: a) providing a detection system forming a narrow aperture positioned in a plane parallel to the material transfer plane in the donor, a photodetector responsive to laser light passing through the narrow aperture to produce a signal, and further providing a controller adapted to produce a first and second series of laser irradiance profiles; b) positioning the multichannel laser printhead in x and y directions parallel to the material transfer plane; c) using a motion control system to sequentially position and scan in a direction perpendicular to the narrow aperture for at least one channel of the multichannel laser printhead and then for at least one other channel of the multichannel laser printhead relative to the aperture from an out-of-focus position through an above focus position so that the controller receives the signals from the photodetector and the motion control system to produce the first and second series of laser irradiance profiles; d) using the first and second series of laser irradiance profiles to determine correction values needed for roll and yaw of the multichannel laser printhead and distance of the multichannel laser printhead from the material transfer plane; e) aligning the multichannel laser printhead in accordance with the correction values whereby the multichannel laser printhead is aligned without performing a thermal transfer operation; and f) establishing the x and y coordinates of each channel of the multichannel laser printhead with respect to x and y coordinates of the motion control system.