The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 17, 1981
Filed:
Feb. 09, 1979
Cecil R Gilbreath, Houston, TX (US);
Geosource, Inc., Houston, TX (US);
Abstract
A high-resolution laser graphics plotter for plotting data on a recording medium as selectively positioned spots (pixels) of variable intensity is disclosed. The intensity of a collimated laser beam is modulated in response to plotting data to produce a modulated light beam. The modulated light beam produces a spot on a light-sensitive film positioned in a flat field image plane. A multi-facet rotating mirror scans the modulated beam across the image plane. A flat field scan lens is positioned between the rotating mirror and the image plane to provide correction for the non-linear velocity of the beam as it is scanned across the image plane, and to provide a constant diffraction limited spot size for each spot plotted. A spot placement means is provided to generate the spot placement signal which cooperates with the plot data to modulate the laser beam. The spot placement means also provides error correction for the facet-to-facet and facet-to-axis errors in the rotating mirror to permit high resolution (500 spots per inch) plotting on wide format film. A micro-stepping motor assembly is provided to advance the film across the image plane.