Mirror tilt actuator
In some embodiments, a depth map acquisition system, includes a housing, a light source for emitting light to illuminate objects in a scene subject to depth mapping, fixedly mounted to the housing, a mirror tilt actuator, fixedly mounted to the housing, for tilting a mirror fixedly mounted to the mirror tilt actuator, a mirror fixedly mounted to the mirror tilt actuator, for reflecting light from the light source to the objects, and a partially transparent photosensitive detector in the direct path of the light from the mirror to the objects.
1. A depth map acquisition system, comprising:
a housing;
a light source for emitting light to illuminate objects in a scene subject to depth mapping, fixedly mounted to the housing;
a mirror tilt actuator, fixedly mounted to the housing, for tilting a mirror fixedly mounted to the mirror tilt actuator;
the mirror, fixedly mounted to the mirror tilt actuator, for reflecting outgoing light from the light source to the objects; and
a partially transparent photosensitive detector in the direct path of the outgoing light from the mirror to the objects;
wherein the depth map acquisition system is to construct, based at least in part on reflected light from the objects, a depth map of the scene.
2. The depth map acquisition system of claim 1 , wherein the mirror tilt actuator comprises:
a base member, fixedly mounted to the housing;
a magnet mount post, fixedly mounted to the base member, for mounting a mirror pivot;
the mirror pivot, comprising a magnetic component, moveably mounted to the magnet mount post, wherein the mirror fixedly mounts to the mirror pivot; and
one or more magnetic coils, fixedly mounted to the base member, for providing one or more magnetic forces to adjust an orientation of the mirror pivot.
3. The depth map acquisition system of claim 1 , wherein the mirror tilt actuator comprises:
a base member, fixedly mounted to the housing;
a magnet mount post, fixedly mounted to the base member, for mounting a mirror pivot;
the mirror pivot, comprising a magnetic component, moveably mounted to the magnet mount post, wherein the mirror fixedly mounts to the mirror pivot;
a ferrous slug, fixedly mounted to the base member beneath the post magnet mount post, for attracting and retaining the mirror pivot by means of a magnetic attraction force between the mirror pivot and the ferrous slug; and
one or more magnetic coils, fixedly mounted to the base member, for providing one or more magnetic forces to adjust an orientation of the mirror pivot.
4. The depth map acquisition system of claim 1 , wherein the mirror tilt actuator comprises:
a base member, fixedly mounted to the housing;
a magnet mount post, fixedly mounted to the base member, for mounting a mirror pivot;
the mirror pivot, comprising a magnetic barrel component, wherein:
the magnetic barrel component is moveably mounted to the magnet mount post, wherein the mirror fixedly mounts to the mirror pivot,
the magnetic barrel component comprises a hollow interior space for mounting to the post, and
the magnetic barrel component comprises a permanent magnet; and
one or more magnetic coils, fixedly mounted to the base member, for providing one or more magnetic forces to adjust an orientation of the mirror pivot.
5. The depth map acquisition system of claim 1 , wherein the mirror tilt actuator comprises:
a base member, fixedly mounted to the housing;
a magnet mount post, fixedly mounted to the base member, for mounting a mirror pivot;
the mirror pivot, comprising a magnetic component, moveably mounted to the magnet mount post, wherein the mirror fixedly mounts to the mirror pivot by means of a mounting post fixedly mounted between the mirror and the mirror pivot; and
one or more magnetic coils, fixedly mounted to the base member, for providing one or more magnetic forces to adjust an orientation of the mirror pivot.
6. The depth map acquisition system of claim 1 , wherein
the partially transparent photosensitive detector in the direct path of the outgoing light from the mirror to the objects further comprises a partially transparent photosensitive detector mounted in the cover glass of a device in which the depth map acquisition system is mounted.
7. The depth map acquisition system of claim 1 , wherein
the partially transparent photosensitive detector in the direct path of the outgoing light from the mirror to the objects further comprises a photosensitive detector in the direct path of a beam of light to a scene to determine the outgoing angle of such light for use in either reconstruction or acquisition of a digital representation of the scene.
8. The depth map acquisition system of claim 1 , wherein the mirror tilt actuator comprises:
a moving magnet, and
four non-moving coils disposed around four sides of the magnet, wherein
when driven with electric signals, the four non-moving coils generate Lorentz forces that tend to tilt the magnet and the mirror about a pivot.
9. The depth map acquisition system of claim 1 , further wherein the mirror tilt actuator comprises:
a base member, fixedly mounted to the housing;
a magnet mount post, fixedly mounted to the base member, for mounting a mirror pivot;
one or more magnetic coils, fixedly mounted to the base member, for providing one or more magnetic forces to adjust an orientation of the mirror pivot; and
the mirror pivot, wherein:
the mirror pivot comprises a magnetic barrel component, and
a fringing field of the moving magnet includes components of magnetic field in the appropriate directions to deliver the Lorentz forces, when the coils are electrically driven.
10. A method for generating a depth map, the method comprising:
a light source emitting light to illuminate objects in a scene subject to depth mapping;
reflecting the light at an outgoing angle using a mirror fixedly mounted to a mirror tilt actuator, for reflecting outgoing light from the light source to one or more objects in the scene;
measuring an outgoing angle of the light using a partially transparent photosensitive detector in a direct path of the outgoing light;
a detector mounted within the housing, receiving reflected light from the objects; and
based on the reflected light, constructing a depth map of the scene.
11. The method of claim 10 , further comprising:
the mirror tilt actuator adjusting a position of the mirror to adjust the outgoing angle.
12. The method of claim 10 , further comprising:
the mirror tilt actuator adjusting a position of the mirror to adjust the outgoing angle by one or more magnetic coils providing one or more magnetic forces to adjust an orientation of a mirror pivot, wherein
the one or more magnetic coils are fixedly mounted to a base member of the mirror tilt actuator,
the mirror pivot comprises a magnetic barrel component,
the magnetic barrel component is moveably mounted to the magnet mount post, wherein the mirror fixedly mounts to the mirror pivot,
the magnetic barrel component comprises a hollow interior space for mounting to the post, and
the magnetic barrel component comprises a permanent magnet.
13. The method of claim 10 , further comprising:
the mirror tilt actuator adjusting a position of the mirror to adjust the outgoing angle based on calculations of a closed loop feedback system in response to the measuring the outgoing angle of the light using the partially transparent photosensitive detector.
14. The method of claim 10 , further comprising
the mirror tilt actuator adjusting a position of the mirror to adjust the outgoing angle of the light by driving electricity though one or more coils disposed about the sides of the mirror pivot to interact with a fringing field of the mirror pivot, wherein the fringing field includes components of magnetic field in the appropriate directions to deliver the Lorentz forces, when the coils are electrically driven.
15. The method of claim 10 , further comprising:
the mirror tilt actuator adjusting a position of the mirror to adjust the outgoing angle by one or more magnetic coils providing one or more magnetic forces to adjust an orientation of a mirror pivot, wherein:
the one or more magnetic coils are fixedly mounted to a base member of the mirror tilt actuator,
the mirror pivot comprises a magnetic barrel component, and
the magnetic barrel component is moveably mounted to the magnet mount post, wherein the mirror fixedly mounts to the mirror pivot.
16. A mirror tilt actuator, comprising:
a base member, fixedly mounted to a housing;
a magnet mount post, fixedly mounted to the base member, for mounting a mirror pivot;
the mirror pivot, comprising a magnetic component, moveably mounted to the magnet mount post, wherein the mirror fixedly mounts to the mirror pivot; and
at least two magnetic coils, fixedly mounted to the base member, for providing at least two magnetic forces to adjust an orientation of the mirror pivot about at least two orthogonal axes relative to a pivot location.
17. The mirror tilt actuator of claim 16 , wherein the mirror tilt actuator further comprises:
a ferrous slug, fixedly mounted to the base member beneath the post magnet mount post, for attracting and retaining the mirror pivot by means of a magnetic attraction force between the mirror pivot and the ferrous slug.
18. The mirror tilt actuator of claim 16 , wherein:
the mirror pivot further comprises a magnetic barrel component,
the magnetic barrel component is moveably mounted to the magnet mount post,
the mirror fixedly mounts to the mirror pivot,
the magnetic barrel component comprises a hollow interior space for mounting to the post, and
the magnetic barrel component comprises a permanent magnet.
19. The mirror tilt actuator of claim 16 , wherein
the mirror fixedly mounts to the mirror pivot by means of a mounting post fixedly mounted between the mirror and the mirror pivot.
20. The mirror tilt actuator of claim 16 , further comprising
four non-moving coils disposed around four sides of the magnet, wherein
when driven with electric signals, the four non-moving coils generate Lorentz forces that tend to tilt the magnet and the mirror about the post in at least two orthogonal axes relative to a pivot location.