Optical feedback locking of semiconductor lasers
First Claim
1. A stabilized semiconductor diode laser system comprising:
- a semiconductor diode laser that emits a beam along a first axis;
said laser having a laser optical field and a carrier densityan optical resonator means, located external to said laser, having a resonator frequency, and including an input port for receiving said laser beam and an output port through which a beam exits said resonator means, said resonator means for producing an enhanced optical output at said output port only when an optical beam supplied at said input port has a frequency substantially equal or exactly equal to said resonant frequency;
first means for optically coupling at least a portion of said beam to said input port; and
second means for optically coupling said output port to said laser as a positive optical feedback thereto whereby inherent coupling of the laser optical field to the carrier density of said laser results in a locking of the laser output frequency.
1 Assignment
0 Petitions
Accused Products
Abstract
An optical method and apparatus is disclosed for stabilizing the frequencyf semiconductor lasers. The basic system includes only the optical elements of a conventional semiconductor laser optically coupled to a separate, external resonator having an optical cavity with a particular resonance frequency. The optical geometry is configured such that the output from the resonator is fed back to the laser only when the laser frequency matches or substantially matches the resonance frequency. In other disclosed embodiments, optical electronic feedback loops are used to modulate the laser injection current to stabilize the frequency and to adjust the phase of the optical feedback signal.
-
Citations
15 Claims
-
1. A stabilized semiconductor diode laser system comprising:
-
a semiconductor diode laser that emits a beam along a first axis;
said laser having a laser optical field and a carrier densityan optical resonator means, located external to said laser, having a resonator frequency, and including an input port for receiving said laser beam and an output port through which a beam exits said resonator means, said resonator means for producing an enhanced optical output at said output port only when an optical beam supplied at said input port has a frequency substantially equal or exactly equal to said resonant frequency; first means for optically coupling at least a portion of said beam to said input port; and second means for optically coupling said output port to said laser as a positive optical feedback thereto whereby inherent coupling of the laser optical field to the carrier density of said laser results in a locking of the laser output frequency. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14)
-
-
15. A method for stabilizing a semiconductor laser that emits a beam comprising:
-
splitting off a portion of said emitted beam to provide a sample beam; coupling said sampled beam to an optical resonator located external to said laser and having a resonant frequency; coupling the output of said resonator back to said laser as a positive feedback only when the frequency of said laser is equal to or substantially equal to said resonant frequency.
-
Specification