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:
Nov. 21, 2000
Filed:
Jul. 07, 1998
Damien F Gray, Austin, TX (US);
DTM Corporation, Austin, TX (US);
Abstract
A laser power control system (150; 150') having a first pulse stretch capability, as may be used in a rapid prototyping system (100), is disclosed. According to one disclosed embodiment, a one-shot multivibrator (156) generates a pulse responsive to a gate signal (LON/LOFF.sub.--) indicating that the laser (110) is to be turned on. The pulse, which is of a selected duration suitable for achieving population inversion, is applied to the laser (110); upon the end of this pulse, pulse-width-modulation (PWM) control of the laser begins. According to another disclosed embodiment, a first pulse stretch store (166) retains a digital value corresponding to the duration by which the first PWM pulse is to be lengthened; adders (176; 178) add this digital value to the parameters indicated by the desired laser power signal (DLP) to ensure population inversion and laser output of the laser (110) in the first pulse.