Projection system with refractive beam steering

• US 9,557,630 B1
• Filed: 06/26/2013
• Issued: 01/31/2017
• Est. Priority Date: 06/26/2013
• Status: Expired due to Fees

• Current Assignee: Amazon Technologies, Inc. (Amazon.com, Inc.)
• Original Assignee: Amazon Technologies, Inc. (Amazon.com, Inc.)
• Inventors: Marason, Eric Gifford, Virgen, Miguel, Coley, Christopher David
• Primary Examiner(s): Le, Bao-Luan
• Assistant Examiner(s): Lamb, II, Christopher
• Application Number:
  US13/928,261
• Time in Patent Office: 1,315 Days
• Field of Search: 353/20, 353/30, 353/28, 353/33, 353/37, 353/73, 353/77, 353/81, 353/98, 353/99, 353/121, 353/122, 359/211.2, 359/211.3, 359/227, 359/237, 359/196.1, 359/197.1, 359/198.1, 359/737, 359/203.1
• US Class Current: 1/1
• CPC Class Codes: G02B 26/0891 forming an optical wedge
• CPC Class Codes: G03B 21/14 Details
• CPC Class Codes: G03B 21/142 Adjusting of projection optics
• CPC Class Codes: G03B 21/2013 Plural light sources
• CPC Class Codes: G03B 21/2033 LED or laser light sources
• CPC Class Codes: G03B 21/26 Projecting separately subsidiary matter simultaneously with main image
• CPC Class Codes: G03B 21/28 Reflectors in projection beam in illumination beam G03B21/2066
• CPC Class Codes: H04N 9/3141 Constructional details thereof details not peculiar to the presence of an electronic spatial light modulator G03B21/14
• CPC Class Codes: H04N 9/317 Convergence or focusing systems electronic adjustment of convergence H04N9/3185; convergence or focusing arrangements for cathode ray tubes H04N9/28; means for automatic focusing of projectors not peculiar to the presence of an electronic spatial light modulator G03B21/53
• CPC Class Codes: H04N 9/3185 Geometric adjustment, e.g. keystone or convergence optical or mechanical adjustment of convergence H04N9/317; using scanning means H04N3/22; optical or mechanical adjustments of projectors not peculiar to the presence of an electronic spatial light modulator G03B21/14
• CPC Class Codes: H04N 9/3194 including sensor feedback

Abstract

A projection system projects images onto a surface as part of an augmented reality environment. Users may interact with the images and this interaction is captured as feedback to the system. The projection system includes a refractive beam steerer to direct the projected images onto specific surfaces within the environment, even if the surfaces are moved about the area. The beam steerer has multiple wedge-shaped prisms that are independently movable to steer the projected light beam as desired. Additionally, an infrared (IR) device may be used to illuminate the environment with IR light, and the IR light may be emitted along a common optical path through the refractive beam steerer as used by the projected light beam.

Claims

1. A device comprising:

at least two color lasers to produce visible light having at least two different wavelengths;

a microelectromechanical system (MEMS) mirror configured to receive the visible light from the at least two color lasers and to reflect portions of the visible light to project an image-bearing light beam into an environment;

multiple independently rotatable prisms to receive the image-bearing light beam from the MEMS mirror and direct the image-bearing light beam to a location in the environment, the multiple independently rotatable prisms comprising at least a first prism having a first shape and a second prism having a second shape different from the first shape, the first prism and the second prism aligned along a center axis and independently rotatable around the center axis to redirect the image-bearing light beam in one of multiple possible directions within the environment;

an infrared (IR) light source configured to emit IR light for illuminating at least a portion of the environment, wherein at least part of the IR light passes through the first prism and the second prism and into the environment where the at least part of the IR light is reflected, as reflected IR light, by an object in the environment; and

a sensor configured to receive at least a portion of the reflected IR light reflected by the object in the environment, wherein the at least the portion of the reflected IR light passes through the first prism and the second prism from the environment to the sensor.

2. The device of claim 1, wherein each of the first prism and second prism have a cylindrical body formed of a glass material and two opposing end surfaces, wherein at least one of the opposing end surfaces is angled relative to the center axis by an angle within a range of 20 degrees and 70 degrees.

3. The device of claim 1, wherein each of the first prism and second prism comprises an achromatic cylindrical body formed of a combination of at least two glasses joined together along angled interfacing surfaces, wherein the at least two glasses comprise a crown glass and a flint glass.

4. The device of claim 1, wherein each of the first prism and second prism comprises a cylindrical body and two opposing end surfaces, the cylindrical body being formed of a combination of at least two glasses joined together along angled interfacing surfaces, wherein both of the two opposing end surfaces are angled relative to the center axis by angles within a range of 20 degrees and 70 degrees and the angled interfacing surfaces are angled relative to the center axis by angles within a range of 40 degrees to 50 degrees.

5. The device of claim 1, wherein the MEMS mirror is a first MEMS mirror, the device further comprising:

a polarizing element to polarize the IR light from the IR light source; and

a second MEMS mirror configured to receive the polarized IR light from the polarizing element and to reflect portions of the polarized IR light through the first prism and the second prism into the environment.

6. A projector system comprising:

a projection component to project light, as projected light, along an optical path, to carry an image onto a surface in an environment;

an infrared (IR) light source configured to emit IR light for illuminating at least a portion of the environment;

a polarizing element to polarize the IR light from the IR light source;

multiple wedge-shaped prisms arranged in the optical path to direct the projected light from the projection component onto the surface in the environment, the multiple wedge-shaped prisms being aligned along a common center axis and each of the multiple wedge-shaped prisms being independently rotatable about the common center axis to control direction of the projected light;

a microelectromechanical system (MEMS) mirror configured to receive the polarized IR light from the polarizing element and to reflect portions of the polarized IR light along the optical path through the multiple wedge-shaped prisms and into the environment; and

a sensor configured to receive, as reflected IR light, at least a portion of the polarized IR light reflected from an object or the surface in the environment, the reflected IR light passing through the multiple wedge-shaped prisms to the sensor.

7. The projector system of claim 6, wherein the projection component comprises a red laser, a blue laser, and a green laser.

8. The projector system of claim 6, wherein the MEMS mirror is a first MEMS mirror, and wherein the projection component comprises:

a laser light source configured to emit visible light; and

a second MEMS mirror to reflect the visible light emitted by the laser light source to form the image.

9. The projector system of claim 6, wherein each of the multiple wedge-shaped prisms comprises a cylindrical body aligned along, and rotatable about, the common center axis.

10. The projector system of claim 6, wherein each of the multiple wedge-shaped prisms comprises a combination of at least two glasses joined together along angled interfacing surfaces, wherein the at least two glasses comprise a crown glass and a flint glass.

11. The projector system of claim 6, wherein each of the multiple wedge-shaped prisms have a cylindrical body with opposing end surfaces, the cylindrical body being aligned along, and rotatable about, the common center axis and at least one of the opposing end surfaces being angled so that the common center axis is not normal to the at least one of the opposing end surfaces.

12. The projector system of claim 11, wherein both of the opposing end surfaces are angled relative to the common center axis within a range from approximately 20 degrees to approximately 70 degrees.

13. The projector system of claim 6, further comprising at least one motor and a mechanical coupling to couple the motor to at least one of the multiple wedge-shaped prisms, wherein the motor is configured to power rotation of the at least one of the multiple wedge-shaped prisms.

14. A device for use in a projection system, the device comprising:

a first wedge-shaped prism having a first sized body aligned along, and configured to rotate about, a center axis, the first wedge-shaped prism having a first end surface through which a light beam enters the first wedge-shaped prism and a second end surface through which the light beam exits the first wedge-shaped prism, at least one of the first and second end surfaces of the first wedge-shaped prism being angled so that the center axis is not normal to the at least one of the first and second end surfaces; and

a second wedge-shaped prism having a second sized body different from the first wedge-shaped prism, the second wedge-shaped prism aligned along, and configured to rotate about, the center axis, the second wedge-shaped prism having a first end surface through which the light beam enters the second wedge-shaped prism and a second end surface through which the light beam exits the second wedge-shaped prism, at least one of the first and second end surfaces of the second wedge-shaped prism being angled so that the center axis is not normal to the at least one of the first and second end surfaces;

wherein the first and second end surfaces of each of the first and second wedge-shaped prisms are angled relative to the center axis within a range from approximately 20 degrees to approximately 70 degrees; and

wherein the first wedge-shaped prism and the second wedge-shaped prism rotate about the center axis independently of each other to collectively direct the light beam into an environment.

15. The device of claim 14, wherein at least one of the first or second wedge-shaped prisms is formed of achromatic glass coated with an antireflection coating.

16. The device of claim 14, wherein each of the first and second wedge-shaped prisms comprises an achromatic cylindrical body formed of a combination of at least two glasses joined together along angled interfacing surfaces, wherein the at least two glasses comprise a crown glass and a flint glass.

17. A method comprising:

receiving a light beam to be projected into an environment;

directing the light beam, using at least a first microelectromechanical system (MEMS) mirror, onto a target surface in the environment to present images on the target surface, the directing comprising;

at least partly refracting the light beam a first time through use of a first wedge-shaped prism having a first size; and

at least partly refracting the light beam a second time through use of a second wedge-shaped prism having a second size different than the first size so that the light beam following the second time of refracting is directed onto the target surface; and

detecting, by a detector, infrared (IR) light reflected by the target surface, the detecting comprising at least directing a reflected portion of the IR light using a second MEMS mirror, the reflected portion of the IR light passing through the first wedge-shaped prism and the second wedge-shaped prism to the detector.

18. The method of claim 17, further comprising rotating at least one of the first wedge-shaped prism or the second wedge-shaped prism to change direction of the light beam within the environment.

19. The method of claim 17, further comprising:

tracking a location of the target surface as the target surface is moved from a first location to a second location within the environment; and

adjusting at least one of the first wedge-shaped prism or the second wedge-shaped prism to direct the light beam from the first location to the second location.

20. The method of claim 19, wherein adjusting at least one of the first wedge-shaped prism or the second wedge-shaped prism comprises rotating the at least one of the first wedge-shaped prism or the second wedge-shaped prism around a center axis.

21. The method of claim 17, further comprising:

receiving the IR light; and

directing the IR light into the environment in substantially the same direction as the light beam using the first wedge-shaped prism and the second wedge-shaped prism.

22. The method of claim 17, wherein the first size of the first wedge-shaped prism is smaller than the second size of the second wedge-shaped prism.

23. The method of claim 17, wherein the first wedge-shaped prism and the second wedge-shaped prism comprise a first optical path, the method further comprising projecting IR light into the environment using a second optical path that is different from the first optical path.