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:
Aug. 23, 2005
Filed:
Apr. 10, 2003
Elizabeth T. Kunkee, Manhattan Beach, CA (US);
David V. Forbes, Oregon, WI (US);
David C. Scott, Lakewood, CA (US);
Timothy A. Vang, San Dimas, CA (US);
Wenshen Wang, Torrance, CA (US);
Elizabeth T. Kunkee, Manhattan Beach, CA (US);
David V. Forbes, Oregon, WI (US);
David C. Scott, Lakewood, CA (US);
Timothy A. Vang, San Dimas, CA (US);
Wenshen Wang, Torrance, CA (US);
Northrop Grumman Corporation, Los Angeles, CA (US);
Abstract
A coupled quantum well Mach-Zehnder modulator that employs a push-pull structure to reduce the modulation voltage. The Mach-Zehnder modulator includes a first arm having a first PIN semiconductor device and a second arm having a second PIN semiconductor device. The intrinsic layers of the PIN devices include a coupled quantum well structure to provide an opposite index of refraction change for different DC bias voltages. An RF signal used to modulate the light beam is applied to the two arms in phase and causes the index of refraction in the intrinsic layers of the two PIN devices to change in opposite directions so that a push-pull type drive is achieved without requiring 180° out-of-phase RF drive signal.