Eyeglasses with embedded femtoprojectors
A pair of electronic eyeglasses includes an eyeglasses frame and an eyeglasses lens mounted within the eyeglasses frame. At least one femtoprojector is embedded within the eyeglasses lens. The femtoprojector includes an image source and an optical system that projects an image from the image source onto the retina of the wearer. The femtoprojector is small enough that is does not significantly interfere with the wearer's view through the eyeglasses lens.
1. Electronic eyeglasses comprising:
an eyeglasses lens mounted within an eyeglasses frame;
at least one femtoprojector embedded within the eyeglasses lens, the femtoprojector comprising an image source and an optical system, the optical system configured to project an image from the image source through a pupil of the wearer's eye and onto the wearer's retina when the wearer's gaze is oriented towards the femtoprojector.
2. The electronic eyeglasses of claim 1 , where the femtoprojector occupies a volume of not more than 2 mm×2 mm×2 mm.
3. The electronic eyeglasses of claim 1 , where the image from the image source is not viewable by the wearer when the wearer gazes straight ahead.
4. The electronic eyeglasses of claim 1 , where the image from the image source is viewable by the wearer when the wearer gazes towards a temporal direction.
5. The electronic eyeglasses of claim 1 , where the image from the image source is viewable by the wearer when the wearer gazes straight ahead.
6. The electronic eyeglasses of claim 1 , where the at least one femtoprojector comprises:
a plurality of femtoprojectors embedded within the eyeglasses lens at different locations, each femtoprojector comprising an image source and an optical system, each optical system configured to project an image from the corresponding image source through a pupil of the wearer's eye and onto the wearer's retina when the wearer's eye is oriented towards that femtoprojector.
7. The electronic eyeglasses of claim 6 where, for any given orientation of the wearer's eye, not all of the images from all of the femtoprojectors are viewable by the wearer.
8. The electronic eyeglasses of claim 6 where, for any given orientation of the wearer's eye, only the image from not more than one femtoprojector is viewable by the wearer.
9. The electronic eyeglasses of claim 1 , where the image projected by the femtoprojector spans at least 5° of the wearer's field of view.
10. The electronic eyeglasses of claim 1 , where the femtoprojector has a resolution of not worse than 2 arc minutes of the wearer's field of view per pixel.
11. The electronic eyeglasses of claim 1 , where the femtoprojector has a magnification of at least 3×.
12. The electronic eyeglasses of claim 1 , where the optical system comprises:
a convex secondary mirror facing the image source, where image-forming rays from the image source are incident on and reflected by the secondary mirror;
a concave primary mirror facing the secondary mirror and further reflecting the image-forming rays from the secondary mirror, the secondary mirror and primary mirror cooperating to project the image from the image source; and
a light baffle system that blocks stray rays from the image source that are not reflected by the secondary mirror.
13. The electronic eyeglasses of claim 1 , where the optical system comprises:
an optically transparent core bounded by a first end and a second end opposite the first end, where the first end is at least as large as the second end;
a sidewall structure that extends between the two ends; and
a lens element positioned at the second end.
14. The electronic eyeglasses of claim 1 , where the image source is an array of LEDs with a pixel-to-pixel pitch of not more than 4 microns.
15. The electronic eyeglasses of claim 1 , further comprising a transparent conductor for transmitting power and/or data to the femtoprojector.
16. The electronic eyeglasses of claim 1 , further comprising a power receiver coil that extends from the temples of the frame and loops around a back of the wearer's head, the power receiver coil configured to receive power wirelessly from a power transmitter coil that is external to the electronic eyeglasses.
17. The electronic eyeglasses of claim 1 , further comprising a capacitor attached to the eyeglasses frame, the capacitor configured to store an amount of energy sufficient for the femtoprojector to operate at a predetermined peak power level for at least a predetermined period of time.
18. The electronic eyeglasses of claim 1 , where the femtoprojector wirelessly receives image data.
19. The electronic eyeglasses of claim 1 , further comprising an ambient light sensor attached to the eyeglasses frame, where a brightness of the image from the image source is adjusted according to the ambient light sensor.
20. The electronic eyeglasses of claim 1 , further comprising an outward-facing camera attached to the eyeglasses frame.