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:
Jul. 25, 1995
Filed:
Nov. 24, 1992
Jun Ohya, Osaka, JP;
Toshihiro Fujita, Osaka, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
In an optical transmission system for transmitting a video signal by transmitting a laser light modulated with a video signal, through an optical fiber; and for receiving and photoelectrically converting the received laser light, a pilot signal is added to the video signal by a summing amplifier. A frequency of the pilot signal is smaller than a band width of the laser light, so that peak level of interference noise developed by multi-reflection at both ends of the optical fiber is decreased considerably. Moreover, in an optical transmission system for transmitting and receiving a video signal by modulating a laser light with the video signal through an optical fiber; and for receiving and photoelectrically converting the received laser light, a polarizing control element is provided in the optical fiber by coiling the optical fiber, so that a signal laser light transmitted without multi-reflection has different retardation from a signal laser light with multi-reflection, so that interference noise is reduced. Similarly, an optical fiber amplifier also employs the polarizing control element to reduce the adverse effect caused by the interference noise.