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:
Jun. 02, 2009
Filed:
May. 23, 2007
Sunao Kakizaki, Kawasaki, JP;
Hideaki Tushima, Tokyo, JP;
Sigeki Kitajima, Kawasaki, JP;
Yasuyuki Fukashiro, Yokohama, JP;
Sunao Kakizaki, Kawasaki, JP;
Hideaki Tushima, Tokyo, JP;
Sigeki Kitajima, Kawasaki, JP;
Yasuyuki Fukashiro, Yokohama, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A method is provided for detecting an optical reflection position in an optical switching unit by using a measuring system. Multiple switching commands are provided in order to direct a test light to an input port and an output port of the optical switching unit. Status information regarding the internal path of the test light is stored in a memory, along with flags corresponding to the magnitude of reflected light generated when the test light is reflected from an abnormal position along the internal path selected. The status information is stored in the form of a reflection alarm information table where the flags are stored in association with each of the internal paths. A rearmost connection among the optical interconnections in the optical switching unit is detected as an abnormal position based on the reflection alarm information table and the interconnection control table.