Integrated dual swept source alternating same scan band 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 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, and a detector system for detecting an interference signal generated from the combined optical signal from the reference arm and from the sample arm.
1. An optical coherence analysis system comprising:
a first swept source that generates a first optical signal that is tuned over a spectral scan band, wherein the first swept source comprises a tunable filter for tuning the first optical signal;
a second swept source that generates a second optical signal that is tuned over same spectral scan band as the first swept source, wherein the second swept source comprises a tunable filter for tuning the second optical signal;
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, the interferometer including a detector system for detecting an interference signal generated from the combined optical signal from the reference arm and from the sample arm; and
a shared tuning controller for controlling the tuning of the first optical signal and the second optical signal over the same spectral scan band by driving the tunable filter of the first swept source and by driving the tunable filter of the second swept source in an alternating time multiplexed fashion.
2. An optical coherence analysis system as claimed in claim 1 , wherein each of the first swept source and the second swept source comprises:
a laser cavity containing the tunable filter and having at least two reflectors, which define the longitudinal cavity modes; and
a semiconductor gain medium in the laser cavity.
3. An optical coherence analysis system as claimed in claim 1 , wherein the tunable filter comprises a Fabry-Perot tunable filter.
4. An optical coherence analysis system as claimed in claim 1 , wherein the tunable filter comprises an angled reflective Fabry-Perot tunable filter.
5. An optical coherence analysis system as claimed in claim 1 , wherein the tunable filter comprises a MEMS Fabry-Perot tunable filter.
6. An optical coherence analysis system as claimed in claim 1 , wherein each of the first swept source and the second swept source comprises:
a broadband source for generating broadband light with the tunable filter spectrally filtering the broadband light from the broadband source to generate a tunable optical signal.
7. An optical coherence analysis system as claimed in claim 6 , wherein each of the first swept source and the second swept source further comprises:
an amplifier for amplifying the tunable optical signal to generate an amplified tunable optical signal; and
a second tunable filter for spectrally filtering the amplified tunable optical signal from the amplifier.
8. An optical coherence analysis system as claimed in claim 6 , wherein the tunable filter comprises a Fabry-Perot tunable filter.
9. An optical coherence analysis system as claimed in claim 6 , wherein the tunable filter comprises a MEMS Fabry-Perot tunable filter.
10. An optical coherence analysis system as claimed in claim 6 , wherein the broadband source is a superluminescent light emitting diode.
11. An optical coherence analysis system as claimed in claim 6 , wherein the broadband source is a semiconductor optical amplifier.
12. An optical coherence analysis system as claimed in claim 1 , further comprising:
an image processing system for constructing an image from a response of the detector system.
13. An optical coherence analysis system as claimed in claim 1 , wherein the combiner comprises a polarization beam combiner.
14. An optical coherence analysis system as claimed in claim 1 , wherein the combiner comprises a beam switch.
15. An optical coherence analysis system as claimed in claim 1 , wherein the first swept source generates the first optical signal with a first polarization and the second sweet source generates the second optical signal with a second polarization which is orthogonal to the first polarization.
16. An optical coherence analysis system as claimed in claim 1 , wherein the detector system comprises a first detector for detecting a portion of the interference signal resulting from the first optical signal and a second detector for detecting a portion of the interference signal resulting from the second optical signal.
17. An optical coherence analysis system as claimed in claim 1 , wherein the shared tuning controller doubles a duty cycle.
18. An optical coherence analysis system as claimed in claim 1 , wherein first swept source and the second swept source are alternately energized so that the first optical signal and the second optical signal are not emitted at the same time.
19. An optical coherence analysis system comprising:
a micro optical bench;
a first source that generates a first optical signal on the micro optical bench, wherein the first source comprises a tunable filter on the micro optical bench for tuning the first optical signal;
a second source that generates a second optical signal on the micro optical bench, wherein the second source comprises a tunable filter on the micro optical bench for tuning the second optical signal;
a combiner, on the optical bench, 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 detector system for detecting an interference signal generated from the combined optical signal from the reference arm and from the sample arm; and
a shared tuning controller for controlling the tuning of the first optical signal and the second optical signal over the same spectral scan band by driving the tunable filter of the first source and by driving the tunable filter of the second source in an alternating time multiplexed fashion.
20. An optical coherence analysis system comprising:
a hermetic package;
a first source that generates a first optical signal in the hermetic package, wherein the first source comprises a tunable filter in the hermetic package for tuning the first optical signal;
a second source that generates a second optical signal in the hermetic package, wherein the second source comprises a tunable filter in the hermetic package for tuning the second optical signal;
a combiner, in the hermetic package, 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 detector system for detecting an interference signal generated from the combined optical signal from the reference arm and from the sample arm; and
a shared tuning controller for controlling the tuning of the first optical signal and the second optical signal over a common spectral scan band by driving the tunable filter of the first source and-by driving the tunable filter of the second source in an alternating time multiplexed fashion.
21. An optical coherence analysis system as claimed in claim 20 , wherein the shared tuning controller doubles a duty cycle.
22. An optical coherence analysis system as claimed in claim 20 , wherein first swept source and the second swept source are alternately energized so that the first optical signal and the second optical signal are not emitted at the same time.