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:
Aug. 20, 1991
Filed:
Mar. 22, 1989
Peter M Rentzepis, Irvine, CA (US);
University of California, Oakland, CA (US);
Abstract
A photoemissive photocathode, preferably tantalum-surfaced cesium-antimonide, is illuminated with pulses of 5320 .ANG. laser light, typically 20 psec. at an 20 Hz repetition rate, to emit electrons by the photoelectric effect. The emitted electrons are accumulated in a spatial region near the photocathode by a grid electrode. The same laser pulses activate a semiconductor switch, normally an LiTaO.sub.3 crystal doped with 2.24% Cu, to apply a high voltage, typically 100 kV, between the photocathode and an anode. The accumulated electrons are accelerated, and focused, as an electron beam that strikes the anode, typically in a focal spot of less than 0.5 mm diameter. Time-resolved x-ray pulses, typically K band of 20 picoseconds duration with 4-10 microjoules energy each, are produced. The x-ray pulses are useable in x-ray lithography, or in x-ray spectroscopy of a specimen in which molecular reaction is initiated and/or energized by the same laser light pulses that also give rise to the x-ray pulses.