Structured and diffuse light generation
An optical device includes an array of light-emitting elements, including a first subset of light-emitting elements and a second subset of light-emitting elements. The first subset of light-emitting elements is configured to emit light having wavelength L 1 . The device includes a high refractive index material selectively disposed on the second subset of light-emitting elements and an array of optical elements positioned so as to be illuminated by the first subset of light-emitting elements and by the second subset of light-emitting elements. The optical elements are regularly arranged in a common plane at a pitch P, the common plane is located a distance D from the array of light-emitting elements, and P 2 ≈2L 1 D/N, N being an integer greater than or equal to 1.
1. An optical device, comprising:
an array of light-emitting elements, comprising a first subset of light-emitting elements and a second subset of light-emitting elements,
wherein the first subset of light-emitting elements is configured to emit light having wavelength L 1 ;
a high refractive index material selectively disposed on the second subset of light-emitting elements but not on the first subset of light-emitting elements; and
an array of optical elements positioned so as to be illuminated by the first subset of light-emitting elements and by the second subset of light-emitting elements,
wherein the optical elements are regularly arranged in a common plane at a pitch P, wherein the common plane is located a distance D from the array of light-emitting elements, and
wherein P 2 ≈2L 1 D/N, N being an integer greater than or equal to 1.
2. The optical device of claim 1 , wherein the second subset of light-emitting elements is configured to emit light having wavelength L 2 , wherein the high refractive index material is configured to impose an effective optical distance D 2 between the second subset of light-emitting elements and the common plane, and
wherein P 2 ≠2L 2 D 2 /N, N being an integer greater than or equal to 1.
3. The optical device of claim 2 , wherein L 1 ≠L 2 .
4. The optical device of claim 1 , wherein P 2 ≈2L 1 D/N to within about 50 μm of effective D.
5. The optical device of claim 1 , wherein the first subset of light-emitting elements and the second subset of light-emitting elements are arranged in a common emitter plane.
6. The optical device of claim 1 , wherein the first subset of light-emitting elements and the second subset of light-emitting elements are arranged in respective non-overlapping areas.
7. The optical device of claim 1 , wherein the first subset of light-emitting elements and the second subset of light-emitting elements are interlaced with one another.
8. The optical device of claim 1 , wherein the first subset of light-emitting elements is arranged in a first pattern, and wherein the second subset of light-emitting elements is arranged in a second pattern different from the first pattern.
9. The optical device of claim 1 , wherein the array of optical elements causes light emitted by each light-emitting element to be transformed into a far field light pattern of regularly spaced light spots, and
wherein the regularly spaced light spots generated by different light-emitting elements of the second subset of light-emitting elements overlap with one another.
10. The optical device of claim 9 , wherein, at a given far-field distance from the array of optical elements, each light spot generated by a light-emitting element of the second subset of light-emitting elements is bigger than each light spot generated by a light-emitting element of the first subset of light-emitting elements.
11. The optical device of claim 1 , wherein the array of optical elements comprises lenses.
12. The optical device of claim 1 , wherein the array of light-emitting elements comprises vertical cavity surface emitting lasers.
13. The optical device of claim 1 , wherein the high refractive index material comprises a curable epoxy.
14. The optical device of claim 1 , wherein the high refractive index material has a refractive index greater than about 1.
15. The optical device of claim 14 , wherein the high refractive index material has a refractive index between about 1.1 and about 2.0.
16. The optical device of claim 15 , wherein the high refractive index material has a refractive index between about 1.4 and about 1.9.
17. The optical device of claim 1 , wherein the high refractive index material has a thickness between about 10 μm and about 300 μm.
18. The optical device of claim 1 , wherein light generated by the first subset of light-emitting elements and passing through the array of optical elements has a regular far field pattern, and
wherein light generated by the second subset of light-emitting elements and passing through the array of optical elements is diffuse in the far field.
19. The optical device of claim 1 , wherein the second subset of light-emitting elements are relatively positioned, with respect to a grid having unit cell spacing P, such that at least a portion of the second subset of light-emitting elements are at different positions with respect to the unit cells in which the light-emitting elements are located.
20. A system comprising:
an optical device in accordance with claim 1 , and
control circuitry configured to cause the first subset of light-emitting elements or the second subset of light-emitting elements to emit light independently of one another.
21. The system of claim 20 , comprising a light-sensing element configured to detect structured light emitted by the optical device.