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:
Sep. 28, 1999
Filed:
Jul. 11, 1997
Arnon Gat, Palo Alto, CA (US);
Robert J Champetier, Scotts Valley, CA (US);
Ram Z Fabian, Haifa, IL;
AG Associates, San Jose, CA (US);
Abstract
The present invention is directed to an apparatus and process for filtering light in a thermal processing chamber. In particular, the apparatus of the present invention includes a first spectral filter spaced apart from a second spectral filter. The first spectral filter is spaced apart from the second spectral filter so as to define a cooling fluid channel therebetween through which a cooling fluid can be circulated. In order to prevent thermal radiation being emitted by the light source from interfering with the operation of a radiation sensing device contained in the chamber, the first spectral filter absorbs most of the thermal radiation being emitted by the light source at the operating wavelength of the radiation sensing device. The second spectral filter, on the other hand, is substantially transparent to thermal radiation at the operating wavelength of the radiation sensing device. If desired, various reflective coatings made from dielectric materials can also be applied to selected surfaces of the spectral filters to further prevent unwanted thermal radiation from being detected by the radiation sensing device and for preventing the spectral filters from increasing in temperature during operation of the chamber.