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:
May. 07, 1996
Filed:
Jun. 25, 1993
Larry R McAdams, Belmont, CA (US);
Optivision Incorporated, Palo Alto, CA (US);
Abstract
A bidirectional optical bus and bus interface. Each functional unit (35, 37) includes an active coupler (60, 70) for each bus line (40a, 40b) with which it is to interface. Each coupler is a four-port device, controllable to assume a desired one of at least two states characterized by different coupling coefficients. In the first state, a significant fraction (possibly all) of the light incoming to the first port (65a) is coupled to the fourth port (65d) and a significant fraction of the light incoming to the second port (65b) is coupled to the third port (65c). In the second state, most of the light incoming to the first port is coupled to the second port with a small fraction coupled to the fourth port, and most of the light incoming to the second port is coupled to the first port with a small fraction coupled to the third port. The couplers for a given bus line are serially connected with their respective first and second ports in line with the optical bus medium, and light is injected into the optical medium from both ends. A functional unit places data onto the bus by controlling its coupler according to a desired data pattern to switch between the first state and another state of significantly lower coupling coefficient.