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. 15, 1994
Filed:
May. 13, 1993
Paul A Johnson, El Cajon, CA (US);
Ri-Chee Chou, San Diego, CA (US);
Chris A Martin, San Diego, CA (US);
Britt Spivey, Encinitas, CA (US);
John Lovberg, San Diego, CA (US);
Thermo Trex Corporation, San Diego, CA (US);
Abstract
A camera system in which microwave radiation from objects in a field-of-view is collected by an antenna having beam directions which are a function of the beam frequency. The collected radiation is used to modulate an optical beam to impose upon the beam spectral components which are functions of the frequencies of the microwave radiation. The modulated beam is then analyzed by an optical spectrum analyzer to produce an image of objects in the field of view. In a simple embodiment of the invention a one dimensional image is produced. This one dimensional image can be converted to a two dimensional image by panning the camera system or mounting the camera on a moving platform. In this preferred embodiment the spectrum analyzer comprises an angle-frequency filter (preferably an etalon). The portion of the modulated beam passing through the etalon is directed in a number of directions, the directions being a function of the spectral components of the modulated beam. The light passing through the etalon is focused on the aperture of a television camera to produce a one dimensional image. In another preferred embodiment an array of antennas and a corresponding number of optical modulators are used to produce a two dimensional real time image. The camera is capable of imaging objects through media such as wooden walls or fog, which are transparent to microwaves, but are opaque to visible light.