Optical means for using diode laser arrays in laser multibeam printers

Abstract

A laser multibeam printer or recorder includes a laser diode array generating multiple modulated parallel and diverging light beams with predetermined light intensities at any instant of time. Optical means reduce the divergence of the parallel light beams from the laser diode array by a predetermined amount, do not focus the light beams in a first cross-section direction along a width of the laser diode array, and focus the light beams onto a plane of an entrance pupil of a printing lens in a second cross-sectional direction normal to the first cross-sectional direction. A separate lenslet of a lenslet array directs a corresponding light beam from the laser diode array towards a predetermined area on a plane in front of the printing lens (e.g., the entrance pupil) in the first cross-sectional direction, and focuses the light beam onto the plane of the entrance pupil in a second cross-sectional direction. The printing lens images the light beams at the entrance pupil onto a light sensitive media as a corresponding array of closely-spaced spots of data with predetermined intensities. Various other arrangements using a field lens in combination with the lenslet array with or without a micro lenslet array can be used to process light beams and form an image of closely-spaced spots of light on the light sensitive media.