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:
Aug. 02, 1994
Filed:
Apr. 05, 1993
Howard E Pollard, Saratoga, CA (US);
Robert E Neff, Fremont, CA (US);
Cheryl J Ajluni, San Jose, CA (US);
Space Systems/Loral, Inc., Palo Alto, CA (US);
Abstract
An optical inspection system for detecting cracks in a crystalline substrate. The crystalline substrate that is to be inspected is located in a test plane in the field of view of a video camera. A first collimated light source projects light which is passed through a long pass filter. The filtered collimated light is projected onto the reflective surface of a panel that contains surface irregularities in the same order as the wavelength of the filtered, collimated light. The light is diffused by the panel surface and reflected onto the crystalline substrate at a plurality of various angles. The light passes through the crystalline substrate and is reflected into the path of the field of view of the video camera and forms an object image from which a real image is created and may be viewed on a control monitor. Cracks in the solar cell silicon layer or glass covers can be observed on the control monitor, and printed by a video graphics printer or stored via a VCR for permanent documentation purposes.