Methods, systems, and devices for timing control in electromagnetic radiation sources
AssigneeLightLab Imaging, Inc.
InventorDesmond Adler
Life of this patent
Estimating the term…
Abstract
In one embodiment, the invention relates to systems, methods and devices for improving the operation of an electromagnetic radiation source or component thereof. In one embodiment, the source is a laser source. A Fourier domain mode locked laser can be used in various embodiments. The sources described herein can be used in an optical coherence tomography (OCT) system such as a frequency domain OCT system. In one embodiment, laser coherence length is increased by compensating for dispersion. A frequency shifter can also be used in one embodiment to compensate for a tunable filter induced Doppler shift.
Claims27
A laser having a wavelength range, a coherence length, and a laser cavity comprising
- an optical delay line;
- a gain element in optical communication with the optical delay line;
- a first optical coupler in optical communication with the gain element;
- a dispersion compensation module in optical communication with the first optical coupler;
- and
- a bi-directionally tunable filter in optical communication with the dispersion compensation module, wherein the gain element, the bi-directionally tunable filter, and the dispersion compensation module are disposed in the laser cavity.
A method of improving coherence length in a laser comprising
- generating a wavelength band using a gain element;
- transmitting the wavelength band through a cavity, the cavity comprising a dispersion compensation element;
- reducing one or both of anomalous dispersion and normal dispersion of the cavity using the dispersion compensation element;
- driving a tunable filter to transmit a subset of the wavelength band and generate an optical frequency sweep;
- and
- coupling out a portion of the optical frequency sweep and transmitting it to an optical coherence tomography probe.
A system comprising
- a source of electromagnetic radiation having a laser cavity and a coherence length comprising a bi-directionally tunable filter disposed in the laser cavity;
- an interferometer in optical communication with the source;
- and
- an optical coherence tomography probe in optical communication with the interferometer, wherein the source comprises a dispersion compensation module configured to reduce at least one of anomalous dispersion or normal dispersion, the dispersion compensation module positioned within the laser cavity.
A laser having a wavelength range and a coherence length comprising
- a gain element;
- a first optical coupler in optical communication with the gain element;
- a tunable filter in optical communication with the first optical coupler;
- a polarization controller in optical communication with the tunable filter;
- an optical frequency shifter in optical communication with the polarization controller;
- a first optical circulator in optical communication with the optical frequency shifter;
- a fiber optic delay line in optical communication with the first optical circulator;
- and
- a reflector in optical communication with the fiber optic delay line.
Dependencies are inferred from the claim text.