Position sensor utilizing light emissions from a lateral surface of an optical fiber
View Patent ↗A position sensor includes a light source, and a light-emitting optical fiber having an insertion end that receives a light input from the light source, and a plurality of light emitters disposed along an emitting length of a lateral surface of a lateral surface of the light-emitting optical fiber. A light-collecting-and-detecting structure is operable to receive light from each of the plurality of light emitters of the light-emitting optical fiber. The light-collecting-and-detecting structure preferably includes a light detector, and a light-collecting optical fiber in a parallel but spaced-apart relation to the light-emitting optical fiber. The light-collecting optical fiber has an extraction end that provides a light output to the light detector, and a plurality of light collectors disposed along a collecting length of a lateral surface of the light-collecting optical fiber in a facing relation to the light emitters of the light-emitting optical fiber. An opaque light shield is disposed between and movable parallel relative to the light-emitting optical fiber and the light-collecting-and-detecting structure, so that a movement of the light shield progressively changes the number of light emitters that are exposed to the light-collecting-and-detecting structure.
1. A position sensor comprising
a light source;
a light-emitting optical fiber having
an insertion end that receives a light input from the light source, and
a plurality of light emitters disposed along an emitting length of a lateral surface of the light-emitting optical fiber;
a light detector;
a light-collecting optical fiber in a parallel but spaced-apart relation to the light-emitting optical fiber and having
an extraction end that provides a light output to the light detector, and
a plurality of light collectors disposed along a collecting length of a lateral surface of the light-collecting optical fiber in a facing relation to the respective light emitters of the light-emitting optical fiber; and
an opaque light shield disposed between and movable parallel relative to the light-emitting optical fiber and the light-collecting optical fiber.
2. The position sensor of claim 1 , wherein the light source is a light-emitting diode.
3. The position sensor of claim 1 , wherein at least some of the light emitters are emitting notches in the light-emitting optical fiber.
4. The position sensor of claim 1 , wherein at some of the light collectors are collecting notches in the light-collecting optical fiber.
5. The position sensor of claim 1 , wherein at least some of the light emitters are roughened emitting surfaces on the light-emitting optical fiber.
6. The position sensor of claim 1 , wherein at least some of the light collectors are roughened collecting surfaces on the light-collecting optical fiber.
7. The position sensor of claim 1 , wherein the light-emitting optical fiber comprises
a second end remote from the insertion end, wherein the second end of the light-emitting optical fiber is internally reflective.
8. The position sensor of claim 1 , wherein the light-collecting optical fiber comprises
a second end remote from the extraction end, wherein the second end of the light-collecting optical fiber is internally reflective.
9. A position sensor comprising
a light source;
a light-emitting optical fiber having
an insertion end that receives a light input from the light source, and
a plurality of light emitters disposed along an emitting length of a lateral surface of the light-emitting optical fiber;
a light-collecting-and-detecting structure operable to receive light from each of the plurality of light emitters of the light-emitting optical fiber; and
an opaque light shield disposed between and movable parallel relative to the light-emitting optical fiber and the light-collecting-and-detecting structure, so that a movement of the light shield progressively changes the number of light emitters that are exposed to the light-collecting-and-detecting structure.
10. The position sensor of claim 9 , wherein each of the light emitters is an emitting notch in the light-emitting optical fiber.
11. The position sensor of claim 9 , wherein each of the light emitters is a roughened emitting surface on the light-emitting optical fiber.
12. The position sensor of claim 9 , wherein the light-collecting-and-detecting structure comprises a light-collecting optical fiber.
13. The position sensor of claim 9 , wherein the light-collecting and detecting structure comprises
a light detector, and
a light-collecting optical fiber in a parallel but spaced-apart relation to the light-emitting optical fiber and having
an extraction end that provides a light output to the light detector, and
a plurality of light collectors disposed along a collecting length of a lateral surface of the light-collecting optical fiber in a facing relation to the light emitters of the light-emitting optical fiber.
14. The position sensor of claim 13 , wherein each of the light collectors is a collecting notch in the light-collecting optical fiber.
15. The position sensor of claim 13 , wherein each of the light collectors is a roughened collecting surface on the light-collecting optical fiber.
16. A position sensor comprising
a light-source-and-light-emitting structure operable to emit light from each of a plurality of light emitters disposed along an emitting length;
a light detector;
a light-collecting optical fiber in a parallel but spaced-apart relation to the light-source-and-light-emitting structure and having
an extraction end that provides a light output to the light detector, and
a plurality of light collectors disposed along a collecting length of a lateral surface of the light-collecting optical fiber in a facing relation to the respective light emitters of the light-source-and-light-emitting structure; and
an opaque light shield disposed between and movable parallel relative to the light-source-and-light emitting structure and the light-collecting optical fiber, so that a movement of the light shield relative to the light-source-and-light emitting structure progressively changes the number of light emitters that are exposed to the light-collecting optical fiber.
17. The position sensor of claim 16 , wherein the light-source-and-light-emitting structure comprises a light-emitting optical fiber.
18. The position sensor of claim 16 , wherein each of the light emitters is an emitting notch in a light-emitting optical fiber.
19. The position sensor of claim 16 , wherein each of the light emitters is a roughened emitting surface on a light-emitting optical fiber.
20. The position sensor of claim 16 , wherein the light-source-and-light-emitting structure comprises
a light source, and
a light-emitting optical fiber in a parallel but spaced-apart relation to the light-collecting optical fiber and having
an insertion end that receives a light output from the light source, and
a plurality of light emitters disposed along an emitting length of a lateral surface of the light-emitting optical fiber in a facing relation to the light collectors of the light-collecting optical fiber.
21. The position sensor of claim 20 , wherein each of the light emitters is an emitting notch in the light-emitting optical fiber.
22. The position sensor of claim 20 , wherein each of the light emitters is a roughened collecting surface on the light-emitting optical fiber.
23. A position sensor comprising
a light source;
a light-emitting optical fiber having
an insertion end that receives a light input from the light source, and
a plurality of light emitters disposed along an emitting length of a lateral surface of the light-emitting optical fiber, wherein at least some of the light emitters are roughened emitting surfaces on the light-emitting optical fiber, wherein no more than 10 percent of the portion of the circumference of the light-emitting optical fiber that is facing the light-collecting optical fiber is roughened;
a light detector;
a light-collecting optical fiber in a parallel but spaced-apart relation to the light-emitting optical fiber and having
an extraction end that provides a light output to the light detector, and
a plurality of light collectors disposed along a collecting length of a lateral surface of the light-collecting optical fiber in a facing relation to the respective light emitters of the light-emitting optical fiber; and
an opaque light shield disposed between and movable parallel relative to the light-emitting optical fiber and the light-collecting optical fiber.