An optical assembly may include a waveguide and a Bragg grating configured to couple light into or out of the waveguide. The Bragg grating may include a plurality of layer pairs, wherein at least one layer pair comprises a first material having a first refractive index and a second layer having a second refractive index, and wherein properties of the Bragg grating are selected so that the Bragg grating exhibits a substantially similar diffractive efficiency and diffraction angle for light of at least two colors.

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.

A glass sheet of the present invention is characterized in that: the glass sheet has a refractive index nd of from 1.55 to 2.30; the glass sheet has an inclined surface in at least a part of an end surface; an angle formed by the inclined surface and a principal surface is from 5° to 85°; and the inclined surface has a surface roughness Ra of 1 μm or less.

An electronic device may have light-emitting devices. A light-emitting device may include light-emitting diodes, a display, or other components that emit visual output. One or more image transport layers may be included in the electronic device. An image transport layer may have an input surface that receives an image and an output surface to which the image transport layer transports the image for viewing by a user. The image transport layers may have areas with compound curvature and other shapes. Deformed image transport layer structures such as deformed fibers in a coherent fiber bundle may be configured to hide gaps in displays and other structures. Displays may include light detectors that serve as a two-dimensional touch sensor. The touch sensor may detect touch input on an output surface of an image transport layer. Image transport layer material may be incorporated into buttons, elongated housings, wearable devices, and other equipment.

A gas detection apparatus 1 includes a substrate 2; a light emitting element 3 provided on a main surface of the substrate for emitting light; a light receiving element 4 provided on the main surface of the substrate 2 for receiving the light; a light guide member 5 for guiding the light emitted by the light emitting element 3 to the light receiving element; a first joint member 6; and a second joint member 7. The first joint member joins the substrate and the light guide member, limits a displacement in a direction parallel and/or orthogonal to the main surface of the substrate. The second joint member joins the substrate and the light guide member, limits a displacement of the light guide member in a direction parallel to the main surface of the substrate and/or limits a displacement within a plane orthogonal to the main surface of the substrate.

A near-eye optical display system that may be utilized in mixed reality applications and devices includes a see-through waveguide on which diffractive optical elements (DOEs) are disposed that are configured for in-coupling, exit pupil expansion, and out-coupling. The optical display system includes a conformal coating that is thickness modulated over different areas of the display to enable tuning of the optical parameters such as refractive index and reflectivity to meet various design requirements. The conformal coating may also be utilized to enhance physical characteristics of the optical display system to thereby improve reliability and resist wear and damage from handling and exposure to environmental elements.

A backlight module applicable to a key module is provided, the key module includes a plurality of key units and a baseplate, and the plurality of key units are disposed on the baseplate. The backlight module includes a lower substrate, a plurality of periphery light sources disposed along the peripheral of the baseplate, and a shielding structure. The lower substrate is disposed below the baseplate, and there is an outer edge gap between an outer edge of the baseplate and the lower substrate. The periphery light sources are disposed between the baseplate and the lower substrate. The shielding structure is disposed outside those periphery light sources distributed, to prevent light provided by the plurality of light sources from being emitted out of the outer edge gap.

An automobile comprises a light transmitting film with a thickness not greater than 0.5 millimeters with a core layer, a lightguide region of the film comprises a light emitting region with light extracting features positioned to receive and extract light from at least one light source propagating by total internal reflection within the core layer out of the core layer, and a light mixing region positioned between the at least one light source and the light emitting region, wherein a surface of the portion of the automobile is visible through the light emitting region of the film when the at least one light source is not emitting light and the light transmitting film is conformal with the surface of the portion of the automobile. The surface of the film may have arcuate cross-sectional shape conforming to a curved surface of the portion of the automobile.

The backlight module includes a backplate, a light guide plate and a light source. The light guide plate includes a body part and a bending part. The body part is located on a side of the backplate facing the display panel, and a surface of the body part facing away from the backplate is an out-light surface. The bending part has a first end face and a second end face. The first end face is connected to the body part, the second end face is located on the side of the backplate facing away from the display panel and is an out-light surface. The light source is located on the side of the backplate facing away from the display panel and opposite to the second end face. The disclosure can achieve a narrower bezel design or bezel-less design.

A backlight module applicable to a key module is provided, the key module includes a plurality of key units and a baseplate, and the plurality of key units are disposed on the baseplate. The backlight module includes a lower substrate, a plurality of periphery light sources disposed along the peripheral of the baseplate, and a shielding structure. The lower substrate is disposed below the baseplate, and there is an outer edge gap between an outer edge of the baseplate and the lower substrate. The periphery light sources are disposed between the baseplate and the lower substrate. The shielding structure is disposed outside those periphery light sources distributed, to prevent light provided by the plurality of light sources from being emitted out of the outer edge gap.