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:
May. 11, 1993
Filed:
Jul. 26, 1991
Victor Vali, Laguna Hills, CA (US);
David B Chang, Tustin, CA (US);
Albert F Lawrence, San Diego, CA (US);
Hughes Aircraft Company, Los Angeles, CA (US);
Abstract
A dislocation-free, composite-substance crystal having a lattice constant which decreases over the length of the crystal (38) convergently focuses beams of hard X-rays or gamma rays (11). A single-substance, dislocation-free crystal (34) collimates diffuse beams of hard X-rays or gamma rays and projects the collimated radiation (11') to the focusing crystal (38). A mask (36) is interposed between the collimating crystal (34) and the focusing crystal (38) causing the collimated radiation (11'') to carry an image of the mask (36). The focusing crystal (38) produces a convergent hard X-ray beam or gamma ray beam (11''') to focus a reduced image of the mask (36) upon the photosensitive layer (41) of a wafer (39). An example of a dislocation-free crystal having a lattice constant which decreases over its length (38) is a dislocation-free silicon-germanium crystal (20) wherein the proportion of germanium to silicon varies over the length of the crystal.