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. 09, 2004
Filed:
Jan. 10, 2003
Peter S. Bui, Westminster, CA (US);
Narayan Dass Taneja, Long Beach, CA (US);
Rapiscan, Inc., Hawthorne, CA (US);
Abstract
The present invention improves the resolution and accuracy of the presently known two-dimensional position sensing detectors and delivers improved performance in the 1.3 to 1.55 micron wavelength region. The present invention is an array of semiconductor layers with four electrodes, the illustrative embodiment comprising a semi-insulating substrate semiconductor base covered by a semiconductor buffered layer, the buffered layer further covered by a semiconductor absorption layer and the absorption layer covered with a semiconductor layer. Four electrodes are placed on this semiconductor array: two on the top layer parallel to each other and near the ends of opposite edges, and two etched in the buffered layer, parallel to each other and perpendicular to the first set. The layers are doped as to make a p-n junction in the active area. Substantially all the layers, excepting the semi-insulating substrate layer, are uniformly resistive.