James C. Owens

Design Of A Compact Diode Laser Color Printer

The optical design of a simple, compact, raster-scanning laser printer using three diode lasers and polygon deflection to produce continuous-tone color prints of high quality on photographic paper is described. Several important optical and calibration problems are discussed, and the results of image quality measurements are summarized.

Single-Mode Fiber Printheads And Scanline Interleaving For High-Resolution Laser Printing

A multiple-laser-diode printhead using a close-spaced array of single-mode optical fibers has been developed for large-format, high-resolution laser printing. This head avoids the output interaction problems of multiple-laser arrays on a single GaAs substrate, while providing small spots, close spacing, low noise, and a compact assembly. Each of the separately packaged laser diodes is controlled by current modulation, and its emission is coupled into the input end of a single-mode optical fiber. The array is made by mounting the fibers in a crystailographically etched set of parallel V-grooves in a silicon wafer. The fibers are specially prepared to allow close spacing. Single-mode fibers are desirable because their outputs can be imaged to give diffraction-limited spots. Close spacing of the multiple sources is desirable because the imaging lens utilizes a smaller field of view and requires less demagnification to give closely spaced scanlines. In order to further reduce the spot spacing to increase spot overlap, the writing head can be tilted with respect to the scanning direction, or the exposure tracks can be interleaved. Tilting requires appropriate pixel-data delays and tighter tolerances on the planarity of the array. A new and more convenient method of interleaving has been developed.