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. 01, 1988
Filed:
Sep. 03, 1987
Larry O Ragle, Palo Alto, CA (US);
Stephen J Davis, San Francisco, CA (US);
Power Spectra, , US;
Abstract
A switch using an improved method of optically-triggered avalanche breakdown which can produce pulses of 100 picoseconds duration that can deliver five kilovolts into 50 ohms using a standard laser diode. A semiconductor block is provided with contacts on opposing sides across which a high-voltage less than the avalanche breakdown voltage is applied. The semiconductor block is then irradiated with electromagnetic radiation. The wavelength of the radiation and the absorption co-efficient of the semiconductor block are chosen so that the absorption depth of the majority of the radiation is less than the distance between the contacts. This results in a photoconduction area where absorption occurs, thus applying most of the high voltage across the distance beyond the photoconduction area. This provides field compression and generates an avalanche breakdown field across the remaining distance of the semiconductor block. Fast switching of large currents is obtained through the dual use of photoconduction as a trigger and subsequent avalanche conduction.