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.

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: 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: 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 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 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: 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.

Abstract: A light-transmitting substrate is deployed with a first of two major surfaces in facing relation to an eye of a viewer and guides light by internal reflection between the two major surfaces. An optical coupling-out configuration couples image light, that corresponds to a collimated image and that is guided by internal reflection between the two major surfaces, out of the light-transmitting substrate. A first optical coupling configuration collimates light from the eye to produce collimated light, and couples the collimated light into the light-transmitting substrate for guiding by internal reflection. A second optical coupling configuration couples the collimated light out of the light-transmitting substrate toward an optical sensor that senses the coupled-out light. A processing system derives current gaze direction of the eye by processing signals from the optical sensor.

Abstract: A receiver for receiving an incident beam of optical power from a remote transmitter over a predefined field of view, comprising an input lens having a high durability coating that can withstand domestic handling and contamination. Such a high durability coating may reflect a non-insignificant part of the light incident thereon. Behind the lens, there is fitted a retroreflector disposed such that it reflects that part of the incident beam traversing the lens, back through the lens to the transmitter. Reflections from the front surface of the lens impinge on one or more transparent beam catchers appropriately located, and equipped with energy conversion devices, such as photovoltaic cells, to convert light from the reflections of the incident beam into electricity. Additional energy conversion devices may be located inward of the lens, to collect and convert reflections from the inner surface of the lens, of light returning from the retroreflector.

Abstract: An optical device has a light-transmitting substrate, an optical coupling-out configuration, and an optical arrangement. The light-transmitting substrate has at least two major surfaces and guides light by internal reflection between the major surfaces. The optical coupling-out configuration couples the light, guided by internal reflection, out of the light-transmitting substrate toward an eye of a viewer. The optical arrangement is associated with at least one of the two major surfaces, and has a first optical element and a second optical element. The optical elements are optically coupled to each other to define an interface region associated with at least a portion of the coupling-out configuration. The interface region deflects light rays that emanate from an external scene that are incident to the optical arrangement at a given range of incident angles.

Abstract: An optical system (100) for directing an image towards a user for viewing includes a light-guide optical element (LOE) (10) having parallel major external surfaces (11a, 11b) for supporting propagation of an image by internal reflection, a coupling-out arrangement for coupling out the image towards an eye of the user, and a coupling-in aperture. An image projector (114) includes an image generator (32) for generating an image, collimating optics (31) for collimating the image, and an image conjugate generator (20, 33, 34). The image projector is coupled to the coupling-in aperture so as to introduce both the collimated image and its conjugate image into the LOE prior to the images impinging on either of major external surfaces. The image conjugate generator may be a second image generator (33), or may employ one or more reflecting surface (22, 23, 24, 34) non-contiguous with the major external surfaces of the LOE.

Abstract: An optical device includes a first waveguide, having parallel first and second faces and parallel third and fourth faces forming a rectangular cross-section, that guides light by four-fold internal reflection and is associated with a coupling-out configuration that couples light out of the first waveguide into a second waveguide. The first or second face is subdivided into first and second regions having different optical characteristics. The optical device also includes a coupling-in configuration having a surface that transmits light into the first waveguide. The surface is deployed in association with a portion of the third or fourth face adjoining the second region such that an edge associated with the surface trims an input collimated image in a first dimension, and a boundary between the first and second regions trims the input collimated image in a second dimension to produce a trimmed collimated image that advances by four-fold internal reflection.

Abstract: A display for providing an image to an eye of a user has a compound light-guide arrangement formed from juxtaposed first and second slab waveguides (10, 20). Image illumination from a projector (100) is introduced, part into each waveguide, so as to propagate by internal reflection within the waveguide. A coupling-out configuration of the first waveguide (10) includes a first set of obliquely-angled internal partially-reflecting surfaces (11) in a first region of the compound light-guide arrangement for coupling-out a first part of the field of view, and a coupling-out configuration of the second waveguide (20) includes a second set of obliquely-angled internal partially-reflecting surfaces (21) in a second region of the compound light-guide arrangement, at least partially non-overlapping with the first region, for coupling-out a second part of the field of view.

Abstract: Disclosed herein is an optical assembly for generating a color image using white light as source. The optical assembly includes a broadband white light source array, a color filter assembly configured to allow selectively filtering therethrough light in each of three additive primary colors, and a control unit. The control unit is configured to actuate light sources in the light source array according to three intensity maps. Each of the intensity maps corresponds to one of the three additive primary colors. The control unit is further configured to synchronize operations of the light source array and the color filter arrangement such that, when light sources in the light source array are actuated according to one of the three intensity maps, the color filter arrangement filters therethrough light at the additive primary color to which the intensity map corresponds.

Abstract: An apparatus (100) for deriving a gaze direction of a human eye (150) includes a light-guide optical element (LOE) (120) having pair of parallel faces (104a), (104b) deployed in facing relation to the eye (150). A coupling-in configuration, such as a set of partially-reflective surfaces (145), is associated with LOE (120) and configured for coupling-in a proportion of light incident on face (104a) so as to propagate within the LOE. Focusing optics (106) associated with LOE (120) converts sets of parallel light rays propagating within the LOE into converging beams of captured light which are sensed by an optical sensor (125). A processing system (108) processes signals from the optical sensor (125) to derive a current gaze direction of the eye. Despite the aperture-combining effect of the LOE, retinal images can be effectively recovered as the only image information brought to focus on the optical sensor.

Abstract: A method of moderating chromaticity of ambient light in an environment reflected back into the environment by a component comprised in a lens of glasses through which a user of views the environment, the method comprising: determining a first set of tristimulus values that characterizes ambient light reflected by the component surface as a function of angle of reflection ? in a bounded span of angles of reflection; determining a second set of tristimulus values for angles in the bounded span of angles so that light characterized by the second set of tristimulus values combined with light reflected by the component would be perceived substantially as white light; and providing an optical coating that reflects ambient light from the environment so that the reflected light is substantially characterized by the second set of tristimulus values.

Abstract: A field of view (FOV) expansion device for use in a near-eye display includes a first surface which receives incident illumination from a projector of departure of the near-eye display. The incident illumination, which may consist of a multiplicity of incident illumination fields is characterized by an incident angular aperture. The expansion device is adjacent to a non-sequential (NS) optical element which projects output light to an observer. The refractive index of the device is greater than that of the NS optical element. A FOV expansion ratio, which is equal to the ratio between a projected angular aperture of the output light and an incident angular aperture of the incident illumination, is greater than or equal to a pre-determined threshold value. The first surface of the FOV expansion device is transparent in one embodiment and reflective in another.

Abstract: An optical device includes a first waveguide, having parallel first and second faces and parallel third and fourth faces forming a rectangular cross-section, that guides light by four-fold internal reflection and is associated with a coupling-out configuration that couples light out of the first waveguide into a second waveguide. The first or second face is subdivided into first and second regions having different optical characteristics. The optical device also includes a coupling-in configuration having a surface that transmits light into the first waveguide. The surface is deployed in association with a portion of the third or fourth face adjoining the second region such that an edge associated with the surface trims an input collimated image in a first dimension, and a boundary between the first and second regions trims the input collimated image in a second dimension to produce a trimmed collimated image that advances by four-fold internal reflection.

Abstract: A display for providing an image to an eye of a user has a compound light-guide arrangement formed from juxtaposed first and second slab waveguides (10, 20). Image illumination from a projector (100) is introduced, part into each waveguide, so as to propagate by internal reflection within the waveguide. A coupling-out configuration of the first waveguide (10) includes a first set of obliquely-angled internal partially-reflecting surfaces (11) in a first region of the compound light-guide arrangement for coupling-out a first part of the field of view, and a coupling-out configuration of the second waveguide (20) includes a second set of obliquely-angled internal partially-reflecting surfaces (21) in a second region of the compound light-guide arrangement, at least partially non-overlapping with the first region, for coupling-out a second part of the field of view.

Abstract: A method of moderating chromaticity of ambient light in an environment reflected back into the environment by a component comprised in a lens of glasses through which a user of views the environment, the method comprising: determining a first set of tristimulus values that characterizes ambient light reflected by the component surface as a function of angle of reflection ? in a bounded span of angles of reflection; determining a second set of tristimulus values for angles in the bounded span of angles so that light characterized by the second set of tristimulus values combined with light reflected by the component would be perceived substantially as white light; and providing an optical coating that reflects ambient light from the environment so that the reflected light is substantially characterized by the second set of tristimulus values.