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:
Apr. 11, 2000
Filed:
Oct. 29, 1997
Satoru Ito, Hakui, JP;
Abstract
A pyroelectric infrared sensor device with improved sensitivity and relative detection rate and reduced manufacturing cost. The infrared sensor device includes a substrate of rectangular shape. The substrate is made of a pyroelectric material, such as tetragonal-system lead titanate pyroelectric ceramics. A pair of comb-shaped electrode patterns each having a set of parallel conductive open-ended fingers are disposed on the top surface of the substrate such that the open-ended fingers of one electrode pattern are spatially interdigitated in relation to those of the other. The paired comb-shaped electrodes have at least three finger pairs whereas the interelectrode distance corresponding to the gap between neighboring fingers is greater than 100 micrometers. These comb-shaped electrodes satisfying the criteria render the pyroelectric material, upon application of a DC voltage between them, substantially horizontally polarizable at or near the top substrate surface which acts as the infrared light receiving plane. An opposite electrode is on the entire bottom surface of the substrate. This electrode has portions insulatively overlapping the comb-shaped electrodes with the pyroelectric material being sandwiched therebetween.