Scanning projectors and image capture modules for 3D mapping

1. Apparatus for mapping, comprising:

a radiation source, which is configured to emit a beam of radiation;

a first scanning mirror, which is configured to receive and scan the emitted beam in a first direction over a selected angular range within a region of interest;

a detector and optics, which define a sensing area of the detector;

a second scanning mirror, which is configured to scan the sensing area over the selected angular range in the first direction in synchronization with the scanned beam from the radiation source;

a scanner, which is configured to scan both the emitted beam and the sensing area over the region of interest in a second direction, which is perpendicular to the first direction; and

a processor, which is configured to process signals output by the detector in order to construct a three-dimensional (3D) map of an object in the region of interest.

2. The apparatus according to claim 1 , wherein the first and second scanning mirrors scan over the region of interest at a first speed, and the scanner scans over the region of interest at a second speed, which is slower than the first speed.

3. The apparatus according to claim 1 , wherein the processor is configured to control the scanning mirrors dynamically so as to modify a scan area of the apparatus.

4. The apparatus according to claim 3 , wherein the processor is configured to identify the object in a first 3D map of the region of interest, and to adjust a scan range of the scanning mirrors based on the first 3D map so as to map the identified object with high resolution in a second 3D map.

5. The apparatus according to claim 1 , wherein the scanner comprises a third scanning mirror.

6. The apparatus according to claim 1 , wherein the scanning mirrors are configured to scan the beam over a first angular range, and

wherein the optics comprise a scan-expanding element, which is configured to distribute the scanned beam so as to cover a second angular range, greater than the first angular range.

7. The apparatus according to claim 6 , wherein the scan-expanding element is selected from a group of elements consisting of a convex reflector and a diffractive optical element.

8. The apparatus according to claim 1 , and comprising at least one beam sensor, which is positioned at a selected angle within the angular range so as to receive the scanned beam periodically and verify thereby that at least the first scanning mirror is operating.

9. The apparatus according to claim 8 , wherein the processor is configured to inhibit emission of the beam from the radiation source when the beam sensor fails to receive the scanned beam periodically.

10. The apparatus according to claim 1 , wherein the first scanning mirror is controllable to dynamically vary the selected angular range, and wherein the second scanning mirror is configured to dynamically scan the sensing area to match the selected angular range of the scanned beam.

11. A method for mapping, comprising:

using a first scanning mirror, scanning a beam of radiation in a first direction over a selected angular range within a region of interest;

using a second scanning mirror, scanning a sensing area of a detector over the selected angular range in the first direction in synchronization with the scanned beam;

scanning both the beam of radiation and the sensing area over the region of interest in a second direction, which is perpendicular to the first direction; and

processing signals output by the detector in order to construct a three-dimensional (3D) map of an object in the region of interest.

12. The method according to claim 11 , wherein scanning the beam of radiation and scanning the sensing area comprise scanning the first and second scanning mirrors over the region of interest in the first direction at a first speed, and wherein scanning both the beam of radiation and the sensing area comprises scanning the beam of radiation and the sensing area over the region of interest in the second direction at a second speed, which is slower than the first speed.

13. The method according to claim 11 , wherein scanning the beam of radiation and scanning the sensing area comprise scanning the first and second scanning mirrors dynamically so as to modify a scan area of the 3D map.

14. The method according to claim 13 , and comprising identifying the object in a first 3D map of the region of interest, and adjusting a scan range of the scanning mirrors based on the first 3D map so as to map the identified object with high resolution in a second 3D map.

15. The method according to claim 11 , wherein scanning both the beam of radiation and the sensing area over the region of interest in a second direction comprises using a third scanning mirror, which rotates in the second direction, to scan both the beam of radiation and the sensing area.

16. The method according to claim 11 , wherein the scanning mirrors are configured to scan the beam over a first angular range, and wherein the method comprises applying a scan-expanding optical element to distribute the scanned beam so as to cover a second angular range, greater than the first angular range.

17. The method according to claim 16 , wherein the scan-expanding optical element is selected from a group of elements consisting of a convex reflector and a diffractive optical element.

18. The method according to claim 11 , and comprising positioning at least one beam sensor at a selected angle within the angular range so as to receive the scanned beam periodically and verify thereby that at least the first scanning mirror is operating.

19. The method according to claim 18 , wherein and comprising inhibiting emission of the beam when the beam sensor fails to receive the scanned beam periodically.

20. The method according to claim 11 , wherein scanning the beam of radiation in the first direction comprises dynamically varying the selected angular range, and wherein scanning the sensing area comprises dynamically scanning the sensing area to match the selected angular range of the scanned beam.