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:
Oct. 18, 1994
Filed:
Jan. 13, 1994
James C Brown, Jr, Brooklyn Center, MN (US);
Sarat K Mohapatra, Woodbury, MN (US);
William C Tait, Oak Park Heights, MN (US);
Minnesota Mining and Manufacturing Company, St. Paul, MN (US);
Abstract
A multi-branch digital optical switch having three branch waveguides through which light may exit. The multi-branch digital optical switch includes a main waveguide, two side branch waveguides, and one center branch waveguide. The two side branch waveguides diverge symmetrically from the center branch waveguide at angles which are sufficiently small to allow modal evolution through the switch to be substantially adiabatic. Electric fields are used to raise the index of refraction of one side branch waveguide above the index of the center branch waveguide and to lower the index of refraction of the other side branch below the index of the center branch waveguide. The switch has an extinction ratio of 700:1 (28 dB) between its two side branches.