Tilted In-Field Light Sources
A near-eye optical element includes light sources arranged with an illumination layer. The light sources are angled to direct light from the light sources to illuminate an ocular region.
1 . A near-eye optical element including:
a transparent substrate having predefined tilted platforms integrated into the transparent substrate; and
a plurality of light sources disposed over the predefined tilted platforms, wherein the predefined tilted platforms are angled to direct the plurality of light sources to illuminate an ocular region.
2 . The near-eye optical element of claim 1 , wherein a tilt angle of a given predefined tilted platform increases as the given predefined tilted platform gets nearer to an outside boundary of the transparent substrate.
3 . The near-eye optical element of claim 1 , wherein a beam direction of a given light source in the plurality of light sources is determined by a tilt angle of a corresponding predefined tilted platform that the light sources are disposed over.
4 . The near-eye optical element of claim 1 , further comprising an illumination film layer including electrical traces configured to provide electrical power to the plurality of light sources, wherein the illumination film layer has the plurality of light sources bonded to the electrical traces, and wherein the illumination film layer is layered over the transparent substrate.
5 . The near-eye optical element of claim 1 , wherein the light sources are in-field light sources positioned to be in a field-of-view (FOV) of a user that is using the near-eye optical element.
6 . The near-eye optical element of claim 1 further comprising:
a transparent encapsulation layer encapsulating the predefined tilted platforms and the plurality of light sources.
7 . The near-eye optical element of claim 6 , wherein the transparent encapsulation layer has a substantially same refractive index as the transparent substrate.
8 . The near-eye optical element of claim 6 , wherein the transparent encapsulation layer includes a lens curvature on an eyeward side of the transparent encapsulation layer.
9 . The near-eye optical element of claim 1 , wherein each light source in the plurality of light sources is configured to emit narrow-band non-visible light.
10 . The near-eye optical element of claim 9 , wherein the light sources include a vertical-cavity surface-emitting laser (VCSEL).
11 . The near-eye optical element of claim 1 further comprising:
a combiner layer configured to receive reflected near-infrared light emitted by the light sources that reflects off the ocular region and direct the reflected near-infrared light to a camera.
12 . The near-eye optical element of claim 1 , wherein a given predefined tilted platform is positioned closer to an eyeward side of the near-eye optical element as a distance of the given predefined tilted platform from an outside boundary of the transparent substrate decreases.
13 . The near-eye optical element of claim 12 , at least a portion of each of the predefined tilted platforms is disposed on a common plane.
14 . A method of fabricating a near-eye optical element comprising:
providing an illumination film layer that includes a plurality of non-visible light sources coupled to electrical traces providing electrical power to the plurality of non-visible light sources;
positioning the illumination film layer over a mechanical fixture configured to define tilted platforms angled to direct the plurality of non-visible light sources to illuminate an ocular region with non-visible light emitted by the non-visible light sources, wherein each non-visible light source in the plurality of non-visible light source has a corresponding tilted platform;
disposing a transparent optical resin over the illumination film layer while the illumination film layer is positioned over the tilted platform; and
curing the transparent optical resin while the illumination film layer is positioned over the mechanical fixture.
15 . The method of claim 14 further comprising:
forming a lens curvature on an eyeward side of the transparent optical resin that is opposite the illumination film layer.
16 . The method of claim 14 further comprising:
removing the mechanical fixture from the illumination film layer after the transparent optical resin is cured; and
forming an optical layer, wherein the illumination film layer is between the optical layer and the cured transparent optical resin.
17 . The method of claim 16 , wherein the optical layer and the cured transparent optical resin have a same refractive index.
18 . The method of claim 14 , wherein the non-visible light sources include a vertical-cavity surface-emitting laser (VCSEL).
19 . A near-eye optical system including:
a plurality of light sources encapsulated within a transparent illumination layer, the light sources being encapsulated within the transparent illumination layer at different angles to direct the plurality of light sources inward to illuminate an ocular region;
a camera; and
a combiner layer configured to direct reflections of non-visible light reflecting from the ocular region to the camera, wherein the non-visible light is emitted by the plurality of light sources, and wherein the camera is configured to image a wavelength range that includes the non-visible light while blocking light wavelengths outside the wavelength range.
20 . The near-eye optical system of claim 19 , wherein the reflections of the non-visible light encounter the transparent illumination layer prior to encountering the combiner layer.