Apparatus and methods for three-dimensional sensing

1. A module comprising:

a rigid-flex printed circuit board;

a light source to output light mounted to the rigid-flex circuit board;

at least one diffractive optical element that diffracts the light;

a first photodiode that is mounted to the rigid-flex circuit board and positioned adjacent to the light source so that a photoreceptor of the photodiode is pointed towards the light source to collect the light that is output by the light source and generate an illumination power signal;

a second photodiode to determine an ambient light signal; and

a fault detector to determine that a fault has occurred based at least in part on a fault detection threshold, the illumination power signal, and the ambient light signal and responsive to determining the fault has occurred, causing the light source to shut down.

2. The projector module of claim 1 , wherein the first photodiode is positioned within a housing of the projector module and the second photodiode is positioned external to the housing.

3. A module comprising:

a semi-conductor substrate;

an array of vertical-cavity surface-emitting laser (VCSEL) elements positioned along the semi-conductor substrate;

a diffractive optical element that diffracts light from the array of VCSEL elements;

a photodiode that is positioned adjacent to the VCSEL elements on the semi-conductor substrate and directed away from the VSCEL elements so that a photoreceptor of the photodiode collects at least a portion of the light diffracted by the diffractive optical element and generate an illumination power signal;

a second photodiode to determine an ambient light signal; and

a fault detector to determine that a fault has occurred based at least in part on a fault detection threshold, the illumination power signal, and the ambient light signal and responsive to determining the fault has occurred, causing the VCSEL elements to shut down.

4. The module of claim 3 , wherein the diffractive optical element diffracts light from the array of VCSEL elements and produces multiple adjacent copies of the light.

5. The module of claim 3 , wherein the photodiode that is positioned within a housing of the projector module.

6. The projector module of claim 5 , wherein the photodiode is positioned in a same direction as the VCSEL elements.

7. A module comprising:

a first camera to capture a first image at a first time;

a second camera to capture a second image at the first time;

a projector, the projector including:

a rigid-flex printed circuit board;

a light source mounted to the rigid-flex printed circuit board;

an optical collimator that collimates light output by the light source; and

a photodiode that is positioned on the rigid-flex printed circuit board adjacent to the light source and such that a photoreceptor of the photodiode is pointed towards the light source to collect the light that is output by the light source;

an error correction and undistortion component to align the first image and the second image;

a depth mask component to determine a depth sensing mask based at least in part on a local image region salience associated with a pixel of the first image;

a matcher component to match the pixel with a region of the second image; and

a depth component to estimate a depth of the pixel based at least in part on a location of the pixel in the first image and a location of the region of the second image.

8. The module of claim 7 , further comprising a housing, the housing having a first opening configured to align with the light source and a second opening configured to align with the photodiode.

9. The module of claim 7 , wherein the light source has an optical axis substantially parallel to an optical axis of the first camera and an optical axis of the second camera.

10. The module of claim 7 , wherein a focal point of the projector is positioned to be substantially collinear with a focal point of the first camera and a focal point of second camera.

11. The module of claim 7 , wherein the light source has an optical axis substantially parallel to an optical axis of the first camera.

12. The module of claim 1 , wherein the first photodiode and the light source are mounted to the rigid-flex printed circuit board.

13. The module of claim 1 , wherein the first photodiode and the light source are mounted in a substantially coplanar alignment to the rigid-flex printed circuit board.

14. The module of claim 1 , wherein the first photodiode is mounted to the rigid-flex printed circuit board.

15. The module of claim 5 , further comprising a thermistor positioned within the housing.

16. The module of claim 3 , further comprising a housing, the housing having a first opening configured to align with the VCSEL elements and a second opening configured to align with the photodiode.

17. The module of claim 3 , wherein the semi-conductor substrate is a rigid-flex printed circuit board.

18. The module of claim 3 , further comprising a thermistor mounted to the semi-conductor substrate.

19. The module of claim 1 , further comprising: at least one optical collimator that collimates the light output by the light source.

20. The module of claim 7 , further comprising:

a reference selection component to select a reference image from a set of one or more reference images; and

wherein the depth component includes a machine learning system to determine the depth of the pixel based at least in part on the local image region, the depth sensing mask, and the reference image.

21. The module of claim 20 , wherein the machine learning system also generates a two-parameter normal vector for the pixel.