Laser transmitter comprising a semiconductor laser and an external resonator

US4831631A · kind A · utility

Assignee

• Siemens Aktiengesellschaft · DE

Inventors

• Klaus M. Haeussler · Munich, DE
• Julius Wittmann · Deisenhofen, DE
• Gisela Gaukel · Munich, DE
• Franz Auracher · Munich, DE

Key dates

• Filing date: Jul 23, 1987
• Grant date: May 16, 1989
• Expiry date: Jul 23, 2007

Classification

• Technology area (CPC G): Physics
• CPC primary: G02B6/243
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

A laser transmitter comprising a semiconductor laser, and an external resonator in the form of an optical directional coupler characterized by feedback device being allocated to a first waveguide of the directional coupler and also a second feedback device allocated to the second waveguide of the coupler, each of the feedback devices returning a portion of the radiant energy in their respective waveguides back along the waveguide to the directional coupler and the output power of the transmitter being taken from the second waveguide of the directional coupler. Preferably, the section of each of the waveguides between the directional coupler and the respective feedback means has a different length with the difference being substantially in the magnitude of the length of the semiconductor laser. Preferably, the waveguides are strip waveguides integrally formed on a substrate and can include a modulator, as well as having the semiconductor laser also integrated on the substrate.