Abstract: A wide field-of-view virtual image projector includes a rod light guide that is embossed with at least a first diffraction grating and a second diffraction grating that is substantially parallel to the first diffraction grating. The first diffraction grating is configured to receive a first light ray, and to project first diffracted light rays from the rod light guide at a first range of angles. The second diffraction grating is configured to receive a second light ray, and to project second diffracted light rays from the rod light guide at a second range of angles. The virtual image projector further includes a slab light guide configured to receive the first diffracted light rays and the second diffracted light rays, and to diffract the first diffracted light rays and the second diffracted light rays out of the slab light guide to generate a virtual image with a wide field-of view.

Abstract: This document describes techniques and apparatuses for implementing a phase control backlight. A phase control backlight is configured to concentrate light to each pupil of a viewer of a display to cause images to be displayed to each pupil of the viewer. The phase control backlight can include an illuminator and a light guide that includes a diffraction grating. The light guide is configured to receive light rays from the illuminator, and to diffract light rays out of the light guide via the diffraction grating. In accordance with various embodiments, the light guide can be controlled to alter a phase of the light rays as the light rays are guided within the light guide to cause the diffracted light rays to converge to a concentration point that corresponds to a position in space of each pupil of the viewer.

Abstract: A wide field-of-view virtual image projector includes a rod light guide that is embossed with at least a first diffraction grating and a second diffraction grating that is substantially parallel to the first diffraction grating. The first diffraction grating is configured to receive a first light ray, and to project first diffracted light rays from the rod light guide at a first range of angles. The second diffraction grating is configured to receive a second light ray, and to project second diffracted light rays from the rod light guide at a second range of angles. The virtual image projector further includes a slab light guide configured to receive the first diffracted light rays and the second diffracted light rays, and to diffract the first diffracted light rays and the second diffracted light rays out of the slab light guide to generate a virtual image with a wide field-of view.

Abstract: This document describes techniques and apparatuses for implementing a phase control backlight. A phase control backlight is configured to concentrate light to each pupil of a viewer of a display to cause images to be displayed to each pupil of the viewer. The phase control backlight can include an illuminator and a light guide that includes a diffraction grating. The light guide is configured to receive light rays from the illuminator, and to diffract light rays out of the light guide via the diffraction grating. In accordance with various embodiments, the light guide can be controlled to alter a phase of the light rays as the light rays are guided within the light guide to cause the diffracted light rays to converge to a concentration point that corresponds to a position in space of each pupil of the viewer.

Abstract: A light guide with input and output faces 2, 3a is polar-symmetric about the first face 2 and has optical properties such that the angle at which a ray is injected into the first face determines the position at which it leaves the second face 3a, or, if operated in the reverse direction, the position at which the ray enters the second face determines the angle at which the ray leaves the second face. The light guide includes a tapered transparent sheet 3, light from the first face entering at the thick end of this sheet, and the second face forming one face of the tapered sheet. An input/output slab 4 adjoins the tapered sheet 3 for fan-out of light from the first face 2 to the tapered sheet, and a transition region 8 is located between flat and tapered sheets. The polar symmetry means that light rays always travel in line with the taper direction, which suppresses banding.

Abstract: A dynamic projected user interface includes a light source for generating a light beam and a spatial light modulator for receiving and dynamically modulating the light beam to create a plurality of display images that are respectively projected onto a plurality of keys in a keyboard. An optical arrangement is disposed in an optical path between the light source and the spatial light modulator for conveying the light beam from the light source to the spatial light modulator.

Abstract: A light guide with input and output faces 2, 3a is polar-symmetric about the first face 2 and has optical properties such that the angle at which a ray is injected into the first face determines the position at which it leaves the second face 3a, or, if operated in the reverse direction, the position at which the ray enters the second face determines the angle at which the ray leaves the second face. The light guide includes a tapered transparent sheet 3, light from the first face entering at the thick end of this sheet, and the second face forming one face of the tapered sheet. An input/output slab 4 adjoins the tapered sheet 3 for fan-out of light from the first face 2 to the tapered sheet, and a transition region 8 is located between flat and tapered sheets. The polar symmetry means that light rays always travel in line with the taper direction, which suppresses banding.

Abstract: A coherent detector which is insensitive to signal or polarization state may be assembled using a fused optical fibre multiport constructed from five optical fibres. The fibres are fused in a circularly symmetric arrangement, then tapered until power injected into any input is equally distributed to all outputs. Reference signals are injected into adjacent inputs and the signal to be detected into a signal adjacent one of the reference inputs.

Abstract: A display video apparatus which provides a three dimensional image broadly comprises a backlighting apparatus for projecting beams of light in selected directions, a spatial light modulator for displaying images back-lit by the back-lighting apparatus, and a control system coupled to both the spatial light modulator and the backlighting apparatus. The control system causes a plurality of images of an object to be formed in succession on the spatial light modulator with each image being a view of the subject from a different angle, and each image being viewable only from particular angles. The images are formed one at a time on the spatial light modulator with a plurality of images constituting a single frame of a video picture. The backlighting apparatus preferably includes a two dimensional display device for emitting spots of light at selected locations along the two dimensional display, and a lens system for refracting light emitted by the two dimensional display device.