Integrated dual swept source for OCT medical imaging
View Patent ↗An optical coherence analysis system comprising: a first swept source that generates a first optical signal that is tuned over a first spectral scan band, a second swept source that generates a second optical signal that is tuned over a second spectral scan band, a combiner for combining the first optical signal and the second optical signal for form a combined optical signal, an interferometer for dividing the combined optical signal between a reference arm leading to a reference reflector and a sample arm leading to a sample, and a detector system for detecting an interference signal generated from the combined optical signal from the reference arm and from the sample arm. In embodiments, the swept sources are tunable lasers that have shared laser cavities.
1. An optical coherence analysis system comprising:
a first swept source that generates a first optical signal that is tuned over a first spectral scan band, the first swept source including a first semiconductor optical amplifier and a first tunable filter for tuning light from the first semiconductor amplifier over the first spectral scan band;
a second swept source that generates a second optical signal that is tuned over a second spectral scan band, the second swept source including a second semiconductor optical amplifier and a second tunable filter for tuning light from the second semiconductor amplifier over the second spectral scan band;
a combiner for combining the first optical signal and the second optical signal to form a combined optical signal;
an interferometer for dividing the combined optical signal between a reference arm leading to a reference reflector and a sample arm leading to a sample;
a multi channel k-clock system for detecting the first optical signal and the second optical signal to generate clock signals, wherein the multi channel k-clock system receives the combined optical signal and separately detects the first optical signal with a first detector to generate a first clock and the second optical signal with a second detector to generate a second clock as the clock signals;
a detector system for detecting an interference signal generated from the combined optical signal from the reference arm and from the sample arm; and
an analog to digital converter system that samples the interference signal and also receives the clock signals.
2. A system as claimed in claim 1 , wherein the combined optical signal is coupled into a spectrally filtering element.
3. A system as claimed in claim 2 , wherein the spectrally filtering element is an etalon.
4. A system as claimed in claim 1 , further comprising an optical bench, on which the first swept source, second swept source and the multi channel k-clock system are implemented.
5. A system as claimed in claim 1 , wherein the multi channel k-clock system comprises a beam splitter for dividing the first optical signal from the second optical signal and providing the first optical signal to the first detector and the second optical signal to the second detector, respectively.
6. A system as claimed in claim 5 , wherein the beam splitter is a WDM filter.
7. An optical coherence analysis method comprising:
generating a first optical signal that is tuned over a first spectral scan band with a first swept source including a first semiconductor optical amplifier and a first tunable filter for tuning light from the first semiconductor amplifier over the first spectral scan band, wherein components of the first swept source are attached to an optical bench;
generating a second optical signal that is tuned over a second spectral scan band with a second swept source including a second semiconductor optical amplifier and a second tunable filter for tuning light from the second semiconductor amplifier over the second spectral scan band, wherein components of the second swept source are attached to the optical bench;
combining the first optical signal and the second optical signal to form a combined optical signal;
dividing the combined optical signal between a reference arm leading to a reference reflector and a sample arm leading to a sample;
detecting the first optical signal and the second optical signal to generate clock signals by receiving the combined optical signal and then separately detecting the first optical signal to generate a first clock with a first detector and the second optical signal to generate a second clock with a second detector; and
processing an interference signal generated from the combined optical signal from the reference arm and from the sample arm in response to the clock signals.
8. A method as claimed in claim 7 , wherein the combined optical signal is coupled into a spectrally filtering element.
9. A method as claimed in claim 8 , wherein the spectrally filtering element is an etalon.
10. A method as claimed in claim 7 , further comprising generating the first optical signals, the second optical signals, and the clock signals on an optical bench.
11. A method as claimed in claim 7 , further comprising dividing the first optical signal from the second optical signal prior to detection by the separate detectors.
12. A method as claimed in claim 11 , further comprising the first optical signal from the second optical signal with a WDM filter.
13. A system as claimed in claim 1 , wherein the multi channel k-clock is attached to the optical bench.
14. A method as claimed in claim 7 , wherein the clock signals are generated by a k-clock system that is attached to the optical bench.