Apparatus and method for space-division multiplexing optical coherence tomography

Patent metadata

Field	Value
Publication number	US-10107616-B2
Application number	US-201615191006-A
Country	US
Kind code	B2
Filing date	Jun 23, 2016
Priority date	Dec 6, 2012
Publication date	Oct 23, 2018
Grant date	Oct 23, 2018

Abstract

A space-division multiplexing optical coherence tomography apparatus and system is provided. In one embodiment, the system includes a light source, a reference arm, and a sample arm. The sample arm splits the sampling light into a plurality of sampling beams which may be scanned simultaneously onto a surface of a sample. An optical delay may be introduced into the sampling beams before scanning. A plurality of reflected light signals returned from the sample is collected. In one arrangement, the signals may be combined to produce a single reflected light signal. The reflected light signal(s) and a reference signal are combined to produce an interference signal comprising data representative of digitized images captured of the actual object. In one embodiment, a single sample arm may be used for scanning and collecting image data. A related method is also provided.

First claim

What is claimed is:

1. A low insertion loss optical coherence tomography system with space-division multiplexing, the system comprising:
a long coherence light source producing coherent light having a coherence length greater than 5 mm to provide optimal imaging depth;
an optical coupler receiving and dividing the light into reference light and sampling light;
a reference arm defining a first optical light path, the reference arm receiving the reference light and generating a reference light signal based on the reference light;
a sample arm defining a second optical light path and receiving the sampling light;
an optical splitter arranged on the sample arm, the optical splitter dividing the sampling light into a plurality of sampling light beams and simultaneously transmitting the plurality of sampling beams;
an optical delay element comprising a plurality of different light path lengths configured and operable to produce an optical delay shorter than the coherence length of the light source between the plurality of sampling beams such that when images are formed, signals from different physical locations are detected in different frequency bands;
a scanner arranged to receive and configured to simultaneously scan the plurality of sampling beams simultaneously onto multiple different sampling locations on a surface of a sample;
a plurality of optical couplers each configured and arranged to simultaneously receive and combine the reference light signal with one of a plurality of individual reflected light signals returned from the multiple different sampling locations on the surface of the sample produced by each of the plurality of sampling beams to simultaneously generate a plurality of interference signals each having a different frequency band; and
a sensor configured to detect and combine the plurality of interference signals;
wherein the interference signals includes data representing digitized images of the sample.

2. The system according to claim 1 , wherein the sensor is a balanced photodetector.

3. The system according to claim 1 , further comprising a plurality of optical circulators each being associated with one of the plurality of optical couplers, each optical circulator being operable to receive one of the plurality of reflected light signals from the sample and transmit the same reflected light signal to one of the optical couplers.

4. The system according to claim 3 , further comprising an optical splitter configured to divide the reference light signal into a plurality of reference light signals, each one of the plurality of reference light signals being transmitted to one of the plurality of optical couplers for producing an interference signal.

5. The system according to claim 1 , wherein the reference arm is a non-sweeping reference arm.

6. The system according to claim 1 , wherein each of the plurality of sampling beams is transmitted by an optical fiber forming an array comprising a plurality of the optical fibers.

7. The system according to claim 6 , wherein each of optical fibers also receives one of the plurality of reflected light signals returned from the multiple different sampling locations on the surface of the sample.

8. The system according to claim 1 , wherein the optical delay element and the optical splitter are replaced by a lightwave circuit which splits the sampling light into the plurality of sampling light beams and produces the optical delay between the plurality of sampling beams which are transmitted simultaneously.

9. The system according to claim 1 , further comprising a high speed data acquisition card and computer processor configured to capture and process the interference signal and generate a visual display of the actual images of the sample on a display device.

10. A low insertion loss optical coherence tomography system with space-division multiplexing, the system comprising:
a long coherence light source producing light having a coherence length greater than 5 mm to provide optimal imaging depth range;
a first optical coupler configured and arranged to split the light into reference light and sampling light;
a non-sweeping reference arm receiving the reference light and producing a reference light signal;
a second optical splitter arranged on a sample arm and configured to split the sampling light into a plurality of sampling beams and transmit the plurality of sampling beams simultaneously;
an optical delay element comprising a plurality of different light path lengths configured to produce an optical delay shorter than the coherence length of the light source between the plurality of sampling beams such that when images are formed, signals from different physical locations are detected in different frequency bands;
a scanner arranged to receive and configured to simultaneously scan the plurality of sampling beams onto multiple different sampling locations on a surface of a sample;
a plurality of third optical couplers each configured and arranged to simultaneously receive and combine the reference light signal with one of a plurality of individual reflected light signals returned from the multiple different sampling locations on the surface of the sample produced by each of the plurality of sampling beams to simultaneously generate a plurality of interference signals each having a different frequency band;
wherein the interference signals includes data representing digitized images of the sample.

11. The system according to claim 10 , wherein the first optical coupler is operable to divert the reference light to the reference arm and to divert the sampling light to the sample arm.

12. The system according to claim 10 , wherein the second optical splitter is an optical fiber splitter.

13. The system according to claim 12 , wherein the optical fiber splitter is planar lightwave circuit splitter.

14. The system according to claim 10 , further comprising a balanced detector sensor arranged and operable to detect and combine the plurality of interference signals from each of the third optical devices.

15. The system according to claim 10 , wherein the optical delay element comprises an optical fiber array comprised of a plurality of optical fibers each having a different length and conveying one of the plurality of sampling beams.

16. The system according to claim 10 , wherein the light source is a wavelength tunable light source.

17. The system according to claim 10 , further comprising a high speed data acquisition card and computer processor configured to capture and process the interference signal and generate a visual display of the actual images of the sample on a display device.

18. The system according to claim 10 , further comprising a plurality of optical circulators each being associated with one of the plurality of optical couplers, each optical circulator being operable to receive one of the plurality of reflected light signals from the sample and transmit the same reflected light signal to one of the optical couplers.

19. The system according to claim 18 , further comprising an optical splitter configured to divide the reference light signal into a plurality of reference light signals, each one of the plurality of reference light signals being transmitted to one of the plurality of optical couplers for producing an interference signal.

20. The system according to claim 10 , wherein the optical delay element and the second optical splitter are replaced by a lightwave circuit which splits the sampling light into the plurality of sampling light b

Assignees

• Univ Lehigh

Inventors

• Zhou Chao

Classifications

• A61B5/0066

  Optical coherence imaging · CPC title

• G01B9/02019

  contacting different points on same face of object · CPC title

• G01B9/02041

  characterised by particular imaging or detection techniques · CPC title

• G01B9/02004

  using frequency scans · CPC title

• G01B9/02028

  Two or more reference or object arms in one interferometer · CPC title