Abstract: An image projector employing a laser scanning illumination arrangement to illumination a spatial light modulator (SLM), where an angular beam spreader element, typically a diffuser or a micro-lens array (MLA), adjacent to, or in a conjugate plane with, the SLM, enhances filling of the exit aperture while minimizing impact on the precision of scanning of the laser illumination on the SLM. Also disclosed are various schemes for synchronous rolling update of the SLM during scanned illumination, and systems employing binary-switchable SLMs.

Abstract: A method of polishing a target surface of a waveguide to achieve perpendicularity relative to a reference surface is disclosed. The method includes i) providing a polishing apparatus having a polishing plate with a flat surface defining a reference plane, and an adjustable mounting apparatus configured to hold the waveguide during polishing at a plurality of angular orientations; ii) positioning an optical alignment sensor and a light reflecting apparatus such that a first collimated light beam is reflected off of a surface parallel to the reference plane, and a second perpendicular collimated light beam is reflected off of the reference surface; iii) aligning the waveguide within the polishing apparatus such that the reflections received by the optical alignment sensor align within the optical alignment sensor, thereby being indicative of perpendicularity between the reference plane and the reference surface; and iv) polishing the target surface of the aligned waveguide.

Abstract: An image projector with a high optical efficiency projects an image at an arbitrary distance from an observer. The image projector includes an illumination module having at least one spatially coherent light source; a phase image generator with an array of optical phase shifting elements; an electronic image controller connected electrically to the phase image generator; and a waveguide which includes at least one embedded partial reflector. The waveguide may be positioned either between the illumination module and the waveguide, or between the waveguide and the observer. The phase image generator may include phase shifts for canceling speckle, correcting optical aberrations, and/or compensating interference caused by light rays having different optical path lengths.

Abstract: An optical aperture multiplier includes a first optical waveguide (10) having a rectangular cross-section and including partially reflecting surfaces (40) at an oblique angle to a direction of elongation of the waveguide. A second optical waveguide (20), also including partially reflecting surfaces (45) at an oblique angle, is optically coupled with the first optical waveguide (10). An image coupled into the first optical waveguide with an initial direction of propagation at an oblique coupling angle advances by four-fold internal reflection along the first optical waveguide, with a proportion of intensity of the image reflected at the partially reflecting surfaces so as to be coupled into the second optical waveguide, and then propagates through two-fold reflection within the second optical waveguide, with a proportion of intensity of the image reflected at the partially reflecting surfaces so as to be directed outwards from one of the parallel faces as a visible image.

Abstract: A display includes a light-guide optical element (LOE) (20) and a projector arrangement (10a) for injecting an image into the LOE so as to propagate within the LOE by internal reflection at a pair of major faces. The image is coupled out from the LOE by a coupling-out arrangement, exemplified here as internal partially-reflecting surfaces (22b). The image is coupled out from the LOE in a direction away from the eye of the observer (24b), and a reflector (30) reflects the coupled-out image back through the LOE (32), towards the eye of the observer (26). Reflector (30) is preferably a selective partial reflector, and may be convex to provide a desired apparent image distance.

Abstract: A projector for projecting an image includes an LED array (2) having separately-controllable LEDs for illuminating a spatial light modulator (SLM) (10) via illumination optics (8) with a converging beam. Projection optics (12) projects the image generated by the SLM. A reflective arrangement (16) typically having four planar reflectors, is deployed between the LED array (2) and the illumination optics (8) so that light from each of LED illuminates a first region of the SLM by direct transmission from the LED via the illumination optics and additional regions of the SLM via reflection in the planar reflectors.

Abstract: An optical system including a light-guide optical element (LOE) with first and second sets (204, 206) of mutually-parallel, partially-reflecting surfaces at different orientations. Both sets of partially-reflecting surfaces are located between parallel major external surfaces. A third set of at least partially-reflecting surfaces (202), deployed at the coupling-in region, receive image illumination injected from a projector (2) with an optical aperture having a first in-plane width and direct the image illumination via reflection of at least part of the image illumination at the third set of at least partially-reflective facets towards the first set of partially-reflective facets with an effective optical aperture having a second width larger than the first width.

Abstract: A display system (500) for displaying an image to an eye of a user includes a light-guide optical element (LOE) (506) and an image projector (512) projecting image illumination of a collimated image into the LOE. The image projector includes an electrically-controllable variable lens (10, 13, 71, 77, 58A, 58B, 59, 58C, 58D, 58E, 58F1, 58F2, 58G1, 58G2, 58H, 1223). A controller (18) determines a current region of interest of the image, either from tracking of the user's eye or by analysis of the image content, and controls the variable lens so as to reduce aberrations in the current region of interest at the expense of increased aberration in at least one area of the image outside the current region of interest.

Abstract: A light-guide device includes a light guiding element (13) with a number of faces, including two parallel faces (26), for guiding light by internal reflection. A transparent optical element (19) has an interface surface for attachment to a coupling surface (14) of the light guiding element, and is configured such that light propagating within the transparent optical element passes through the interface surface and the coupling surface (14) so as to propagate within the light guiding element (13). A non-transparent coating (15) is applied to at least part of one or more faces of the light guiding element (13), defining an edge (17) adjacent to, or overlapping, the coupling surface (14) of the light guiding element (13). A quantity of transparent adhesive is deployed between the coupling surface and the interface surface so as to form an optically transmissive interface. An overspill region 31 of the adhesive extends to, and overlaps, the edge (17).

Abstract: An image projector employing a laser scanning illumination arrangement to illumination a spatial light modulator (SLM), where an angular beam spreader element, typically a diffuser or a micro-lens array (MLA), adjacent to, or in a conjugate plane with, the SLM, enhances filling of the exit aperture while minimizing impact on the precision of scanning of the laser illumination on the SLM. Also disclosed are various schemes for synchronous rolling update of the SLM during scanned illumination, and systems employing binary-switchable SLMs.

Abstract: An image projector with a high optical efficiency projects an image at an arbitrary distance from an observer. The image projector includes an illumination module having at least one spatially coherent light source; a phase image generator with an array of optical phase shifting elements; an electronic image controller connected electrically to the phase image generator; and a waveguide which includes at least one embedded partial reflector. The waveguide may be positioned either between the illumination module and the waveguide, or between the waveguide and the observer. The phase image generator may include phase shifts for canceling speckle, correcting optical aberrations, and/or compensating interference caused by light rays having different optical path lengths.

Abstract: An image projector employing a laser scanning illumination arrangement to illumination a spatial light modulator (SLM), where an angular beam spreader element, typically a diffuser or a micro-lens array (MLA), adjacent to, or in a conjugate plane with, the SLM, enhances filling of the exit aperture while minimizing impact on the precision of scanning of the laser illumination on the SLM. Also disclosed are various schemes for synchronous rolling update of the SLM during scanned illumination, and systems employing binary-switchable SLMs.

Abstract: An image projector includes an illumination arrangement with a number of illumination sources and a tilt-mirror assembly, all operating under control of a controller. An optical arrangement directs illumination from the illumination sources towards the mirror and on to an image plane. A collimating arrangement collimates the illumination from the image plane to generate a collimated image directed to an exit stop. The controller (830) modulates an intensity of each of the illumination sources (808) synchronously with tilt motion of the mirror (814) according to the content of the digital image. In certain implementations, the illumination sources (808) are spaced apart. Although the tilt motion brings each illumination source to scans across only part of a dimension of the field of view, all of the illumination sources together scans across the entirety of the one dimension.

Abstract: A method for generating an image in a near-eye display may include operating a light source to emit the image as incident light. The light source may be configured such that incident light as received by the light reflecting elements compensates for the chromatic reflectance of the light reflecting elements. The method may include coupling the incident light into a light-transmitting substrate, thereby trapping the light between first and second major surfaces of the light-transmitting substrate by total internal reflection and coupling the light out of the substrate by the light reflecting elements having chromatic reflectance.

Abstract: A method for generating an image in a near-eye display may include operating a light source to emit the image as incident light. The light source may be configured such that incident light as received by the light reflecting elements compensates for the chromatic reflectance of the light reflecting elements. The method may include coupling the incident light into a light-transmitting substrate, thereby trapping the light between first and second major surfaces of the light-transmitting substrate by total internal reflection and coupling the light out of the substrate by the light reflecting elements having chromatic reflectance.

Abstract: A method of fabricating an optical aperture multiplier is provided. A slice and a first optical structure are obtained. The slice has external faces including a pair of parallel faces, and a first plurality of partially reflective internal surfaces oblique to the pair of parallel faces. The first optical structure has external surfaces including a planar coupling surface, and a second plurality of partially reflective internal surfaces oblique to the coupling surface. The slice is optically coupled with the first optical structure such that one of the faces of the pair of parallel faces is in facing relation with the coupling surface to form a second optical structure. At least one optical aperture multiplier is sliced from the second optical structure by cutting the second optical structure through at least two cutting planes perpendicular to the coupling surface. The optical aperture multiplier is preferably part of a near eye display augmented reality system.

Abstract: A display and method for providing an image to an eye of a viewer is provided. The display comprises at least two projector assemblies. Each projector assembly comprises a lightguide optical element (LOE), and an image projector arrangement for generating a partial image and being deployed to introduce the partial image into the LOE for coupling out towards the eye of the viewer. The at least two projector assemblies cooperate to display the image to the eye of the viewer with partial overlap. The display further comprises a controller associated with the image projector arrangements and configured to reduce a pixel intensity of selected pixels in a region of partial overlap between the first and second part of the image so as to enhance a perceived uniformity of the image.

Abstract: An optical assembly for optical aperture expansion combines facet reflective technology with diffractive technology. At least two diffractive components having opposite optical power (matching) are used, so that chromatic dispersion introduced by the first diffractive component will then be cancelled by the second diffractive component. The two diffractive components are used in combination with a reflective optical component to achieve more efficient aperture expansion (for near eye display), reducing distortions and noise, while also reducing design constraints on the system and individual components, as compared to conventional techniques. The assembly eliminates and/or reduces the need for polarization management, while enabling wider field of view. In addition, embodiments can have reduced nonuniformity, as compared to conventional single technology implementations, since the distortion patterns of the two technologies do not correlate.

Abstract: A transparent substrate has two parallel faces and guides collimated image light by internal reflection. A first set of internal surfaces is deployed within the substrate oblique to the parallel faces. A second set of internal surfaces is deployed within the substrate parallel to, interleaved and in overlapping relation with the first set of internal surfaces. Each of the internal surfaces of the first set includes a first coating having a first reflection characteristic to be at least partially reflective to at least a first subset of components of incident light. Each of the internal surfaces of the second set includes a second coating having a second reflection characteristic complementary to the first reflection characteristic to be at least partially reflective to at least a second subset of components of incident light. The sets of internal surfaces cooperate to reflect all components of light from the first and second subsets.

Abstract: An optical system including a light-guide optical element (LOE) with first and second sets (204, 206) of mutually-parallel, partially-reflecting surfaces at different orientations. Both sets of partially-reflecting surfaces are located between parallel major external surfaces. A third set of at least partially-reflecting surfaces (202), deployed at the coupling-in region, receive image illumination injected from a projector (2) with an optical aperture having a first in-plane width and direct the image illumination via reflection of at least part of the image illumination at the third set of at least partially-reflective facets towards the first set of partially-reflective facets with an effective optical aperture having a second width larger than the first width.