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: A head-mounted augmented reality device (10) includes a pair of optical modules (12) for the right and left eyes of the user, each having a collimating display source (14) optically coupled to a light guide (16) for directing image illumination towards an eye of the user. A support structure (20) is supported by the head of the user. An optical bench (22) provides a first set of alignment features (26, 28, 32, 74) for aligning and affixing the right optical module and a second set of alignment features (26, 28, 32, 74) for aligning and affixing the left optical module. A suspension arrangement suspends the optical bench relative to the support structure. The optical bench (22) provides the sole mechanical connection between the pair of optical modules (12) and the support structure (20).

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 first dichroic beamsplitter is deployed in a first prism on a plane oblique to a light-wave entrance surface. A second dichroic beamsplitter is deployed in a second prism on a plane oblique to a light-wave entrance surface such that polarized light in a first polarization state relative to the first dichroic beamsplitter is in a second polarization state relative to the second dichroic beamsplitter. The first dichroic beamsplitter transmits polarized light of a first color in the first polarization state relative to the first dichroic beamsplitter, and reflects polarized light of a second color in the first polarization state relative to the first dichroic beamsplitter. The second dichroic beamsplitter transmits polarized light of the first and second colors in a second polarization state relative to the second dichroic beamsplitter, and reflects polarized light of a third color in the first polarization state relative to the second dichroic beamsplitter.

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 light pipe includes at least two optical structures having different refractive indices. An interface between the two optical structures is oblique to a longitudinal axis of the light pipe such that an output ray from an output surface at a distal end of the light pipe is non-parallel to an input ray that is parallel to the longitudinal axis at an input surface at a proximal end of the light pipe. Light refracts inside the light pipe between the (at least) two optical structures altering the direction of an optical path of the light through the light pipe, thereby allowing higher degrees of freedom for the selection of the angle of deviation (folding angle) of the light pipe. By optimizing various parameters of the light pipe, a desired output optical axis angle (i.e., folding angle) can be achieved that suits the desired optical engine envelope.

Abstract: A method for producing light-guide optical elements (LOEs) (16, 18, 56, 58) each having a set of mutually-parallel partially-reflecting surfaces (17) located between, and oriented non-parallel to, a pair of major external surfaces, and at least one region (30a, 30b, 30c) without partially-reflecting surfaces. The method includes bonding together parallel-faced plates (4) at interfaces to form a stack (42) of plates with partially-reflecting coatings between them. The stack is cut and polished to form a boundary plane (48, 48a, 48b) intersecting the interfaces, and a block (50, 50a, 50b) of transparent material is bonded to the stack. The resulting precursor structure (52, 52?) is sliced along parallel planes to form slices, each containing a part of the stack for the active region of the LOE and a part of the block.

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: A light-transmitting substrate has parallel surfaces deployed with a first of the parallel surfaces in facing relation to an eye. An optical element is associated with the first surface and applies optical power to incident light of a first type so as to collimate the incident light, and applies substantially no optical power to incident light of a second type. An optical coupling configuration is associated with the substrate and is configured for coupling-in a proportion of collimated light of the first type incident on the first surface so as to propagate within the substrate, and for coupling-out a proportion of light of the second type propagating within the substrate. Optics associated with the substrate convert collimated light of the first type into converging beams of light, which are sensed by an optical sensor. A processor derives current gaze direction of the eye by processing signals from the optical sensor.

Abstract: An optical system for displaying an image includes a waveguide (10) having two major surfaces (12, 14) that support propagation of image illumination by internal reflection. A coupling-out configuration (16, 18) couples out image illumination towards the eye of the user. An image projector (20) is coupled so as to introduce image illumination into the waveguide so as to propagate by internal reflection. The waveguide also contains a symmetrical beam multiplier region, distinct from the coupling-out region, having one or more beam splitters (24) internal to the waveguide and parallel to its major surfaces. The symmetrical beam multiplier may be used to fill in a conjugate image after a compact coupling-in configuration, and/or may be used to fill the waveguide with the image as an intermediate stage (36) between two optical aperture expansion configurations (32, 34).

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 optical system has a hollow mechanical body having first and second ends. An optical assembly has a plurality of optical components arranged in a stack configuration. Each of the optical components has a set of engagement configurations. For each pair of adjacent optical components in the stack configuration, at least some of the engagement configurations of a first optical component in the pair engage with at least some of the engagement configurations of a second optical component in the pair. Some of the engagement configurations of the optical component at a first end of the stack configuration engage with corresponding engagement configurations of the hollow mechanical body at the first end of the hollow mechanical body to position the other optical components of the stack configuration within the hollow mechanical body. An emissive display device is deployed at the second end of the hollow mechanical body.

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: A method of fabricating a compound light-guide optical element (LOE) is provided. A bonded stack of a plurality of LOE precursors and a plurality of transparent spacer plates alternating therebetween is bonded to a first optical block having a plurality of mutually parallel obliquely angled internal surfaces. The block is joined to the stack such that first plurality of partially reflective internal surfaces of the block is non-parallel to the internal surfaces of the LOE precursor. After bonding, a second optical is thereby formed. At least one compound LOE is sliced-out of the second optical block by cutting the second block through at least two consecutive spacer plates having a LOE precursor sandwiched therebetween.

Abstract: There is provided an optical system, including a light-transmitting substrate (20) having at least two major surfaces (26) and edges, all optical prism (54) having at least a first (58), a second (56) and a third (60) surface, for coupling light waves having a given field-of-view into the substrate by total internal reflection, at least one partially reflecting surface located in the substrate, the partially reflecting surface being orientated non-parallelly with respect to the major surfaces of the substrate, for coupling light waves out of the substrate, at least one of the edges (50) of the substrate is slanted at an oblique angle with respect to the major surfaces, the second surface of the prism is located adjacent to the slanted edge of the substrate, and a part of the substrate located next to the slanted edge is substantially transparent, wherein the light waves enter the prism through the first surface of the prism, traverse the prism without any reflection and enter the substrate through the slanted

Abstract: A method for generating an image in a near-eye display may include dividing an image into first and second sub-images, sequentially transmitting the first sub-image and the second sub-image through a channel, extracting light corresponding to the first sub-image in a first polarization and light corresponding to the second sub-image in a second polarization, deflecting a first order of the light in the first polarization in a first direction, and deflecting an opposite order of the light in the second polarization in a opposite direction different from the first direction. The resulting image width corresponding to a wider field of view.

Abstract: A stack has first and second faces and multiple LOEs that each has two parallel major surfaces and a first plurality of parallel internal facets oblique to the major surfaces. A first block has third and fourth faces and a second plurality of parallel internal facets. The first block and the stack are bonded such that the second face joins the third face and the first and second facets are non-parallel, forming a second block. The second block is cut at a plane passing through the first face, forming a first structure having an interfacing surface. A third block has fifth and sixth faces and a plurality of parallel internal reflectors. The third block and the first structure are bonded such that fifth face joins the interfacing surface and the internal reflectors are non-parallel to all the facets, forming a second structure. Compound LOEs are sliced-out from the second structure.

Abstract: An optical system provides two-stage expansion of an input optical aperture for a display based on a light-guide optical element. A first expansion is achieved using two distinct sets of mutually-parallel partially-reflecting surfaces, each set handing a different part of an overall field-of-view presented to the eye. In some cases, a single image projector provides image illumination to two sets of facets that are integrated into the LOE. In other cases, two separate projectors deliver image illumination corresponding to two different parts of the field-of-view to their respective sets of facets.