Mode locking methods and apparatus
AssigneeMassachusetts Institute of Technology
InventorsRobert Huber, Kenji Taira, James Fujimoto
Life of this patent
Estimating the term…
Abstract
In one aspect the invention relates to a frequency varying wave generator. The generator includes a gain element adapted to amplify a wave having a wavelength; a time varying tunable wavelength selective filter element in communication with the gain element, the tunable filter element adapted to selectively filter waves during a period T; and a feedback element in communication with the tunable filter element and the gain element, wherein the tunable wavelength selective filter element, the gain element and the feedback element define a circuit such that the roundtrip time for the wave to propagate through the circuit is substantially equal to a non-zero integer multiple of the period T.
Claims53
A frequency varying wave generator comprising:
- a gain element adapted to amplify a wave having a wavelength;
- a time varying tunable wavelength selective filter element in communication with the gain element, the tunable filter element adapted to selectively filter waves during a period T;
- and
- a feedback element in communication with the tunable filter element and the gain element,
- wherein the tunable wavelength selective filter element, the gain element and the feedback element define a circuit such that the roundtrip time for the wave to propagate through the circuit is substantially equal to a non-zero integer multiple of the period T.
An apparatus adapted for generating waves having temporally varying frequencies, the apparatus comprising:
- a gain element adapted for amplifying waves having different wavelengths;
- a time varying tunable wavelength selective filter element;
- a feedback element in communication with the gain element and the tunable filter element
- the tunable filter element, gain element and feedback element defining a circuit such that the roundtrip time of the wave substantially equals a non-zero integer multiple of a periodic time T during which the tunable filter element is tuned.
A method of frequency sweeping a wave generator comprising a gain element, a tunable filter having a tuning time period T in communication with the gain element and a feedback element in communication with the tunable filter and the gain element, the tunable filter, gain element and feedback element defining a circuit, the method comprising the steps of:
- generating waves;
- and
- periodically tuning a tunable filter over a period T, such that the waves travel from the filter element through the circuit and back to the filter element during a time which is a non-zero integer multiple of time T.
A laser for generating light having time varying wavelengths, the laser comprising:
- a gain element having a spectral bandwidth;
- a time varying, tunable optical bandpass filter having an optical pass band that is varied during a substantially periodic time T;
- and
- a feedback element in communication with the gain element and the filter, forming a laser resonator, wherein the roundtrip time of the optical waves in the resonator is substantially equal to a non-zero integer multiple of the time T.
Dependencies are inferred from the claim text.