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:
Jun. 21, 1994
Filed:
Nov. 02, 1992
Ting K Yee, Foster City, CA (US);
James F Coward, San Jose, CA (US);
Peter H Chang, San Jose, CA (US);
Other;
Abstract
A Mach-Zehnder modulator (MZM), which divides a CW laser beam into two optical portions, is biased at a 180.degree. phase difference between the two optical portions. An RF signal and an LO signal are simultaneously applied to one of the optical portions of the laser beam to produce phase changes between the two optical portions. The two optical portions of the laser beam are then recombined into an optical output beam, which is detected by a photodetector. The photodetector generates a photocurrent, which contains a component at a beat frequency--i.e., the frequency difference between the RF and LO frequencies. The waveform of the photocurrent component at the beat frequency is substantially the same (except for amplitude and a fixed phase shift) as the waveform of the RF signal.