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:
Apr. 23, 1991
Filed:
May. 12, 1989
Rodney C Alferness, Holmdel, NJ (US);
Zigmantas L Budrikis, Dalkeith, AU;
David W Hagelbarger, Nederland, CO (US);
Herwig W Kogelnik, Rumson, NJ (US);
Arun N Netravali, Westfield, NJ (US);
AT&T Bell Laboratories, Murray Hill, NJ (US);
Abstract
An arrangement for butt coupling of waveguide electrooptic plates to form a crossbar switch. The arrangement includes a stack of M splitter plates, each of which routes an injected optical signal to one of N outputs, and a stack of N combiner plates, each of which routes the signal of a selected one of M inputs to a common output. The stack of splitter plates is rotated with respect to the stack of combiner plates and the output signal ports of the splitter plates are coupled to the input signal ports of the combiner plates, so that each output of an splitter plate is connected to a different combiner plate. Within each splitter plate there is a fan-out network of waveguide electrooptic couplers and each coupler, under electric control, routes signals from one input to either one of two outputs. With j levels of such interconnected couplers 2.sup.j output are developed. The combiner plates have an identical architecture but with a signal flow in the reverse direction. Butt coupling of the splitter and combiner plates is achieved by employing splitter and combiner plates of a different crystal cut, by interposing polarization rotation means between two stacks, or by including polarization rotation means within the splitter plates, the combiner plates or both.