Light-collimating tank for use with an optical computed tomography system

• US 10,670,874 B2
• Filed: 03/30/2018
• Issued: 06/02/2020
• Est. Priority Date: 03/30/2017
• Status: Active Grant

• Current Assignee: Duke University
• Original Assignee: Duke University
• Inventors: Oldham, Mark, Miles, Devin
• Primary Examiner(s): Ko, Tony
• Application Number:
  US15/941,149
• Publication Number:
  US 20180284473A1
• Time in Patent Office: 795 Days
• CPC Class Codes: G01B 9/02091 Tomographic interferometers, e.g. based on optical coherence
• CPC Class Codes: G02B 27/30 Collimators
• CPC Class Codes: G02B 3/12 Fluid-filled or evacuated lenses

Abstract

An optical computed tomography system for comprehensive end-to-end verification of the delivered dose in phantoms is described. The optical computed tomography system includes a light source that emits light; a detector; and a light-collimating tank arranged between the light source and the detector. The light-collimating tank itself includes a transparent substrate having a recessed region formed therein; an incident light surface formed on the transparent substrate; and an exit light surface formed on the transparent substrate opposite the incident light surface and shaped to focus light toward a focal region located outside of the transparent substrate. In some configurations, the incident light surface is shaped to collimate light impinging on the incident light surface into parallel rays that pass through the tank towards the exit light surface.

Claims

1. A light-collimating tank for an optical computed tomography scanner, comprising:

a transparent substrate having a recessed region formed therein;

an incident light surface formed on a first side of the transparent substrate; and

an exit light surface formed on a second side of the transparent substrate that is opposite the first side, the exit light surface being shaped to focus light toward a focal region located outside of the transparent substrate.

2. The light-collimating tank as recited in claim 1, wherein the incident light surface is shaped to collimate light incident on the incident light surface into parallel rays that pass through the recessed region of the transparent substrate toward the exit light surface.

3. The light-collimating tank as recited in claim 2, wherein the incident light surface is shaped into a convex lens.

4. The light-collimating tank as recited in claim 2, wherein the incident light surface is shaped into a Fresnel lens.

5. The light-collimating tank as recited in claim 1, further comprising a parallel collimator arranged at the incident light surface such that light incident on the parallel collimator is collimated into parallel rays that impinge upon the incident light surface.

6. The light-collimating tank as recited in claim 5, wherein the parallel collimator is a parallel-hole collimator.

7. The light-collimating tank as recited in claim 5, wherein the parallel collimator is a collimating lens.

8. The light-collimating tank as recited in claim 1, wherein the transparent substrate comprises polyurethane.

9. The light-collimating tank as recited in claim 1, wherein the exit light surface is shaped into a convex lens.

10. The light-collimating tank as recited in claim 1, wherein the recessed region is cylindrical in shape.

11. An optical computed tomography system, comprising:

a light source that emits light;

a detector that detects light; and

a tank arranged between the light source and the detector, comprising;

a transparent substrate having a recessed region formed therein;

an incident light surface formed on the transparent substrate;

an exit light surface formed on the transparent substrate opposite the incident light surface and shaped to focus light toward the detector.

12. The optical computed tomography system as recited in claim 11, wherein the incident light surface is shaped to collimate light incident on the incident light surface into parallel rays that pass through the recessed region of the transparent substrate toward the exit light surface.

13. The optical computed tomography system as recited in claim 11, further comprising a parallel collimator arranged at the incident light surface such that light incident on the parallel collimator is collimated into parallel rays that impinge upon the incident light surface.

14. The optical computed tomography system as recited in claim 11, wherein the light source comprises a light emitting diode.

15. The optical computed tomography system as recited in claim 14, wherein the light source comprises an array of light emitting diodes.

16. The optical computed tomography system as recited in claim 11, wherein the detector further comprises a focusing lens interposed between the exit light surface and the detector to refocus scattered light exiting the exit light surface to impinge onto the detector.

17. The optical computed tomography system as recited in claim 11, further comprising an aperture interposed between the exit light surface and the detector.

18. The optical computed tomography system as recited in claim 11, further comprising a rotation stage onto which the tank is positioned such that when the rotation stage is rotated the tank is similarly rotated through a plurality of different view angles.

19. The optical computed tomography system as recited in claim 11, wherein the transparent substrate is composed of a material having a refractive index that is matched to a refractive index of a dosimeter to be placed into the recessed region for optical scanning.

20. The optical computed tomography system as recited in claim 11, further comprising a diffuser located between the light source and the incident light surface of the tank.

21. The optical computed tomography system as recited in claim 20, further comprising a parallel collimator positioned between the diffuser and the incident light surface of the tank.

22. The optical computed tomography system as recited in claim 21, wherein the parallel collimator is a parallel-hole collimator.

23. The optical computed tomography system as recited in claim 21, wherein the parallel collimator is a collimating lens.