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 surface-relief grating comprises a plurality of grating ridges including a first material, and a layer of a second material conformally deposited on surfaces of the plurality of grating ridges. A first region of the surface-relief grating is characterized by a first grating depth and a first duty cycle greater than a first threshold value. A second region of the surface-relief grating is characterized by a second grating depth and a second duty cycle lower than a second threshold value that is lower than the first threshold value. A difference between the first grating depth and the second grating depth is less than 20% of the second grating depth.

The present disclosure relates to a backlight module, a display device and a control method thereof. The display device includes a first edge, a second edge, and N display areas. The N display areas are disposed between the first edge and the second edge and are arranged along the first direction; the first edge and the second edge are arranged along the first direction; the method includes: in response to a first control instruction for entering an anti-peeping display mode, controlling the display device to enter the anti-peeping display mode, wherein after the display device enters the anti-peeping display mode, among the display areas disposed between a central axis of the display device and the first edge, brightness of a display area closer to the first edge is lower than brightness of a display area closer to the central axis, and among the display areas disposed between the central axis and the second edge, brightness of a display area closer to the second edge is lower than brightness of a display area closer to the central axis, where the central axis is parallel to the first edge.

A display apparatus includes a guide element, and an incident optical system causing light from a display element to enter the guide element. The guide element includes a first light guide part guiding the light from the incident optical system in a first direction and a second light guide part guiding the light from the first light guide part in a second direction intersecting with the first direction. The first light guide part has mirrors disposed along the first direction and guiding the light to the second light guide part by reflection. The mirrors include a first mirror and a second mirror. Each of the first and second mirrors has a first reflection region and a second reflection region having a higher reflectance than the first reflection region. Light having transmitted through the first reflection region of the first mirror enters the second reflection region of the second mirror.

According to one embodiment, an electronic device includes a liquid crystal panel and an illumination unit which illuminates the liquid crystal panel. The illumination unit includes a light guide comprising a first side surface, a main surface opposing the liquid crystal panel and an opening made by a notch or a through hole, a first light source opposing to the first side surface, and a second light source provided closer to the opening than to the first light source.

The present disclosure generally pertains to a device for a liquid crystal display, including: a light directing portion for guiding light of a first wavelength range from a light source to a plurality of quantum dots, wherein the light directing portion includes a light directing branching; and the plurality of quantum dots configured to emit light of a second wavelength range in response to light of the first wavelength range being incident on a plurality of display elements, each display element including a subset of the plurality of quantum dots, thereby defining a predetermined quantum dot pattern corresponding to the light directing branching.

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.

A backlight source is provided which includes a light guide plate 10 and a light-emitting unit 20. The light guide plate 10 includes a first surface and a second surface disposed oppositely. The light-emitting unit 20 is located on the side of the light guide plate where the first surface disposed. The grating layer 30 includes at least one grating unit configured to diffract light emitted by the light-emitting unit 20. The overall structure of the backlight source is no longer limited by the distance between the LEDs and the first layer diffusion layer, and therefore the thinning and lightening of the backlight source is realized. A manufacturing method of a backlight source and a display device are further provided.

A holographic display device including a field lens focusing a three-dimensional (3D) image reproduced by a holographic display, wherein the field lens includes an anisotropic diffractive lens functioning as a lens with respect to a specific polarization.

An illumination device includes a frame forming part that is provided at at least one position on an end part of a light-emitting panel having a light emission surface or in a vicinity of the light-emitting panel and includes a bright part region and a dark part region, a light source that emits light to be incident upon the frame forming part, and a light amount regulation part that makes intensity of light heading for a space facing the light emission surface from the dark part region weaker than intensity of light heading for the space from the bright part region in the light entering the frame forming part from the light source, or makes the intensity of the light from the bright part region stronger than the intensity of the light from the dark part region in the light entering the frame forming part from the light source.