Testing device for laser illumination systems

Patent metadata

Field	Value
Publication number	US-10145730-B2
Application number	US-201514975889-A
Country	US
Kind code	B2
Filing date	Dec 21, 2015
Priority date	Dec 21, 2015
Publication date	Dec 4, 2018
Grant date	Dec 4, 2018

Abstract

Apparatus and methods are described, including an apparatus for testing a light beam emitted by a light source. The apparatus includes a transparent substrate, a first face of the substrate being shaped to define a plurality of optical deflectors. At least one optical detector is positioned to face a second face of the substrate that is not opposite the first face. Each one of the deflectors is configured to deflect a portion of the light beam toward the detector, when the light beam is passed through the first face of the substrate. Other applications are also described.

First claim

The invention claimed is:

1. An apparatus, comprising:
a transparent substrate, a first face of the substrate being shaped to define a plurality of optical deflectors; and
at least one optical detector positioned to face a second face of the substrate that is not opposite the first face,
each one of the deflectors being configured to deflect a portion of a light beam, which is emitted through the substrate by a light source, toward the detector, upon the light beam passing through the first face of the substrate.

2. The apparatus according to claim 1 , wherein the optical detector is coupled to the second face of the substrate.

3. The apparatus according to claim 1 , wherein the first face of the substrate is shaped to define the plurality of optical deflectors by being shaped to define a plurality of prism-shaped indentations.

4. The apparatus according to claim 1 , wherein the first face of the substrate is shaped to define the plurality of optical deflectors by being shaped to define a plurality of pyramid-shaped indentations.

5. The apparatus according to claim 1 , further comprising the light source.

6. The apparatus according to claim 1 , wherein the substrate is shaped to define a flat plate.

7. The apparatus according to claim 1 , wherein the substrate is shaped to define a lens.

8. The apparatus according to claim 1 , wherein a third face of the substrate that is opposite the first face is shaped to define a diffractive optical element.

9. The apparatus according to claim 1 , wherein a third face of the substrate that is opposite the first face is a light-diffusing face.

10. The apparatus according to claim 1 , further comprising a diffractive optical element (DOE), wherein a third face of the substrate that is opposite the first face is coupled to the DOE.

11. The apparatus according to claim 1 , wherein a first one of the deflectors is (i) farther from the detector than a second one of the deflectors, and (ii) larger than the second one of the deflectors.

12. The apparatus according to claim 1 , wherein a first area of the first face is farther from the detector than a second area of the first face, and wherein the deflectors are distributed more densely in the first area than in the second area.

13. The apparatus according to claim 1 , wherein a length of each of the deflectors is between 10 and 200 micrometers.

14. The apparatus according to claim 1 , wherein the optical detector is configured to generate a signal in response to detecting the deflected portion of the light beam, and wherein the apparatus further comprises a processor configured to:
receive the signal, and
in response to the signal, generate an output that is indicative of an angular spread of the light beam.

15. The apparatus according to claim 14 , wherein the processor is further configured to, in response to a magnitude of the signal exceeding a threshold, inhibit operation of the light source.

16. A method, comprising:
using a light source, emitting a light beam through a transparent substrate that includes a first face shaped to define a plurality of optical deflectors, such that, upon the light beam passing through the first face of the substrate, a portion of the light beam is deflected by the deflectors toward an optical detector positioned to face a second face of the substrate that is not opposite the first face;
using the optical detector, detecting the deflected portion of the light beam, and generating a signal in response thereto; and
using a processor, receiving the signal, and in response to the signal, generating an output that is indicative of an angular spread of the light beam.

17. The method according to claim 16 , further comprising using the processor to inhibit operation of the light source, in response to a magnitude of the signal exceeding a threshold.

18. A method for use with a transparent substrate having (i) a first face, and (ii) a second face that is not opposite the first face, the method comprising:
positioning an optical detector to face the second face of the substrate; and
shaping the first face of the substrate to define a plurality of optical deflectors, each one of the deflectors being configured to deflect a portion of a light beam, which is emitted through the substrate by a light source, toward the detector, upon the light beam passing through the first face of the substrate.

19. The method according to claim 18 , wherein shaping the first face of the substrate to define the plurality of optical deflectors comprises shaping the first face of the substrate to define a plurality of prism-shaped indentations.

20. The method according to claim 18 , wherein shaping the first face of the substrate to define the plurality of optical deflectors comprises shaping the first face of the substrate to define a first deflector and a second deflector, the first deflector being (i) farther from the detector than the second deflector, and (ii) larger than the second deflector.

Assignees

• Apple Inc

Inventors

• Fournier Florian R
• Scepanovic Miodrag

Classifications

• G01J1/4228

  arrangements with two or more detectors, e.g. for sensitivity compensation · CPC title

• G02B27/108

  for sampling a portion of a beam or combining a small beam in a larger one, e.g. wherein the area ratio or power ratio of the divided beams significantly differs from unity, without spectral selectivity · CPC title

• G01J1/4257 Primary

  applied to monitoring the characteristics of a beam, e.g. laser beam, headlamp beam (monitoring arrangements for lasers in general H01S3/0014) · CPC title

• G02B27/143

  using macroscopically faceted or segmented reflective surfaces · CPC title

• G02B27/4233

  having a diffractive element [DOE] contributing to a non-imaging application (diffusers having a diffractive element G02B5/0252; filters having a diffractive element G02B5/203; systems for controlling the direction of light having diffractive elements G02B26/0808; scanning systems having diffractive elements G02B26/106; beam shaping systems using diffractive optical elements G02B27/0944; beam splitting or combining systems operating by diffraction G02B27/1086) · CPC title