Optical coherence tomography eye imaging techniques
Aspects of the present disclosure provide improved techniques for imaging a subject's retina fundus. Some aspects relate to an imaging apparatus that may be substantially binocular shaped and/or may house multiple imaging devices configured to provide multiple corresponding modes of imaging the subject's retina fundus. Some aspects relate to techniques for imaging a subject's eye using white light, fluorescence, infrared (IR), optical coherence tomography (OCT), and/or other imaging modalities that may be employed by a single imaging apparatus. Some aspects relate to improvements in white light, fluorescence, IR, OCT, and/or other imaging technologies that may be employed alone or in combination with other techniques. Some aspects relate to multi-modal imaging techniques that enable determination of a subject's health status. Imaging apparatuses and techniques described herein provide medical grade retina fundus images and may be produced or conducted at low cost, thus increasing access to medical grade imaging.
1. An apparatus for performing optical coherence tomography (OCT) on a retina fundus of a subject, the apparatus comprising:
a plurality of light sources configured to emit light at a plurality of wavelengths;
at least one optical component configured to combine the light from the plurality of light sources into an elongated line;
an interferometer configured to:
receive the elongated line of light from the at least one optical component;
divide the elongated line of light among reference components and sample components;
illuminate an eye of the subject with the elongated line of light via the sample components, the elongated line of light being substantially perpendicular to a depth direction into the eye; and
recombine received light from the reference components and the sample components;
an image sensor configured to detect the received light from the interferometer after recombination; and
a transmissive grating positioned between the interferometer and the image sensor and configured to spread the received light by wavelength over the image sensor.
2. The apparatus of claim 1 , wherein some of the plurality of light sources are configured to emit light of a different wavelength than others of the plurality of light sources.
3. The apparatus of claim 1 , wherein the interferometer is a Michelson interferometer.
4. The apparatus of claim 1 , wherein the plurality of light sources comprise a plurality of light emitting diodes.
5. The apparatus of claim 1 , further comprising at least one dichroic mirror configured to combine the light from the plurality of light sources into a single optical path.
6. The apparatus of claim 1 , wherein the plurality of light sources comprise three light sources.
7. The apparatus of claim 6 , wherein the three light sources comprise:
a first light source configured to emit light with a central wavelength between 620 nm and 630 nm;
a second light source configured to emit light with a central wavelength between 635 nm and 645 nm; and
a third light source configured to emit light with a central wavelength between 650 nm and 660 nm.
8. The apparatus of claim 7 , wherein:
the first light source is configured to emit light with a central wavelength of 625 nm;
the second light source is configured to emit light with a central wavelength of 640 nm; and
the third light source is configured to emit light with a central wavelength of 655 nm.
9. The apparatus of claim 1 , wherein the plurality of light sources are configured to emit light sequentially.
10. The apparatus of claim 9 , wherein the image sensor is configured to detect the recombined light associated with each of the plurality of light sources sequentially.
11. The apparatus of claim 10 , further comprising at least one processor configured to:
receive image data associated with the recombined light from the image sensor, wherein the image data comprises separate image data associated with each of the plurality of light source components; and
combine the image data associated with each of the plurality of light sources into a single OCT image.
12. An apparatus for performing optical coherence tomography (OCT) on a retina fundus of a subject, the apparatus comprising:
a light source configured to emit light;
at least one optical component configured to form the light from the light source into a scanning line;
an interferometer configured to:
receive the scanning line of light from the light source;
divide the scanning line of light between reference components and sample components;
illuminate an eye of the subject with the scanning line of light via the sample components, the scanning line being substantially perpendicular to a surface of the eye, and the sample components configured to scan the scanning line across the surface of the eye in a direction substantially perpendicular to the scanning line; and
recombine received light from the reference and sample components; and
an image sensor configured to detect the received light from the interferometer.
13. The apparatus of claim 12 , wherein the sample components are configured to focus the scanning line at the retina fundus of the subject and the reference components are configured to focus the scanning line at a reference surface.
14. The apparatus of claim 12 , wherein the interferometer is a Michelson interferometer.
15. The apparatus of claim 12 , wherein the at least one optical component comprises a first cylindrical lens pair located between the light source and the interferometer.
16. The apparatus of claim 15 , further comprising a second cylindrical lens pair located between the interferometer and the image sensor.
17. The apparatus of claim 12 , further comprising a transmissive grating located between the interferometer and the image sensor.
18. The apparatus of claim 12 , wherein the sample components comprise a scanning mirror configured to scan the scanning line at the retina fundus of the subject in the direction substantially perpendicular to the scanning line.
19. The apparatus of claim 12 , wherein the image sensor is configured to detect the recombined light from the interferometer such that different portions of the image sensor correspond to different portions of the retina fundus illuminated by the scanning line.
20. The apparatus of claim 12 , further comprising a fixation display configured to provide a moving fixator object for the eye of the subject to track to scan the scanning line across the eye.