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.

A lightguide for conveying image light to an eyebox of a display device includes a tunable grating, e.g. an out-coupling grating for out-coupling the image light from the lightguide. The tunable grating may be tuned or switched to effectively diffract light of a color channel of a color-sequential display. In augmented reality display systems, a lightguide combiner element may include a switchable grating to out-couple the image light only during short time intervals and to not out-couple the image light in between these time intervals. Effectively, the out-coupling grating is present only a portion of overall operation time of the display, which improves the transparency of the combiner element to the outside light and reduces rainbow effects.

A lightguide for conveying image light to an eyebox of a display device includes a tunable grating, e.g. an out-coupling grating for out-coupling the image light from the lightguide. The tunable grating may be tuned or switched to effectively diffract light of a color channel of a color-sequential display. In augmented reality display systems, a lightguide combiner element may include a switchable grating to out-couple the image light only during short time intervals and to not out-couple the image light in between these time intervals. Effectively, the out-coupling grating is present only a portion of overall operation time of the display, which improves the transparency of the combiner element to the outside light and reduces rainbow effects.

A display apparatus includes a lightguide for conveying images to a user in a target field-of-view (FOV). The lightguide includes a tunable output diffraction grating for displaying different portions of the target field-of-view at different time instances. The tunable output diffraction grating may include grating segments that are selectively switchable between a diffracting state and a non-diffracting state in dependence on a content of an image being displayed, providing content-dependent FOV switching.

One embodiment provides an apparatus for displaying an image comprising: a first optical substrate comprising at least one waveguide layer configured to propagate light in a first direction, wherein the at least one waveguide layer of the first optical substrate comprises at least one grating lamina configured to extract the light from the first substrate along the first direction; and a second optical substrate comprising at least one waveguide layer configured to propagate the light in a second direction, wherein the at least one waveguide layer of the second optical substrate comprises at least one grating lamina configured to extract light from the second substrate along the second direction; wherein the at least one grating lamina of at least one of the first and second optical substrates comprises an SBG in a passive mode.

A backlight unit 10 for an outside mirror of a vehicle may comprise: a light source unit 30 including at least one light source 31 disposed therein; a light processing unit 40 having at least one light passage 41 through which light emitted from the light source 31 passes while being diffused, and a reflective surface 42 for reflecting the light having passed through the light passage 41; and a photorefractive means 60 which is disposed at a light exit of the light processing unit and refracts light emitted from the light exit of the light processing unit to be oriented toward a driver's seat.

Disclosed in various embodiments of the present document are: a structure including a nonmetallic material and guiding, in one direction, light incident on one side; and an electronic device including the structure in an inner space thereof. According to the various embodiments, provided is an electronic device comprising: a housing having an inner space, and including an outer surface facing a first direction, an inner space facing the direction opposite to the first direction, and a display unit which is formed between the outer surface and the inner space and which has a thickness through which light passes through; a printed circuit board arranged in the inner space; at least one light-emitting element arranged in the inner space; and a nonmetallic structure arranged in the inner space, wherein the nonmetallic structure includes: a first part having a light guide between the light-emitting element and the display unit and including a transparent or translucent first material; a second part which is integrally formed with the first part, includes the first material, and is directly or indirectly fixed to the printed circuit board or the housing; and a third part encompassing at least a portion of the light guide and including a translucent second material. The nonmetallic light guide structure and the electronic device including same can be varied according to embodiments.

A backlight unit includes a light source having an emission region, a wiring board having the light source mounted thereon, a light guide plate having a side surface into which light from the light source enters, and a front surface from which the light exits, a light shielding adhesive tape adhering to the wiring board, and an optical sheet which overlaps with the front surface of the light guide plate. The front surface of the light guide plate includes an effective region serving as a planar light source and a light entering region ranging from the side surface to the effective region. The wiring board and the light-shielding adhesive tape each have a part positioned in the light entering region, and the optical sheet is arranged from the effective region to the light entering region. An end portion of the optical sheet overlaps with the light-shielding tape.

A head mounted display (HMD) device and method of manufacturing the same. The HMD includes a frame housing a micro-display to project display light, a lightguide configured to receive the display light from the micro-display, and a corrective layer having a world-side surface coupled to the eye-side surface of the lightguide. The lightguide is further configured to have a world-side surface with a radius of curvature based on an ophthalmic corrective prescription and an eye-side surface having an outcoupler feature formed thereon such that the coupled lightguide and corrective layer form a lens configured to fit within the frame.

A system such as a vehicle may have windows. A window may have a structural window layer such as a structural window layer formed from laminated glass layers. A thin chemically strengthened glass layer may be coupled to an inwardly facing surface of the structural window layer. A guest-host liquid crystal light modulator layer or other electrically adjustable optical component layer may be interposed between the chemically strengthened glass layer and the structural window layer. An infrared light-blocking coating may be formed on an inwardly facing surface of one of the pair of laminated glass layers. The inwardly facing surface of the thin chemically strengthened glass layer may be provided with a coating that includes a low emissivity layer to block heat and that serves as an antireflection coating.