A planar light source includes: a light guide member, a light source including a light-emitting element and a first light adjustment member and being disposed in a first hole of the light guide member, a first light-transmissive member disposed in the first hole between a lateral surface of the light source and the light guide member and on the light source, and a second light adjustment member disposed on the first light-transmissive member. A transmittance of the first light-transmissive member is higher than a transmittance of the first light adjustment member and a transmittance of the second light adjustment member with respect to light emitted from the light source. The first light-transmissive member includes a first light-transmissive portion 1ocated between the first light adjustment member and the second light adjustment member, and a second light-transmissive portion 1ocated between the lateral surface of the light source and the light guide member.

An optical device, having at least first and second light-transmitting substrates, each having at least two external surfaces and an input aperture and an output aperture. The external surface of the first light-transmitting substrate is optically cemented to an external surface of the second light-transmitting substrate by an optical adhesive defining an interface plane. The refractive index of the optical adhesive is substantially lower than the refractive index of the first substrate. Part of the light waves entering the device through the input aperture and exiting the device through the output aperture impinge on the interface plane of the first substrate having incidence angles smaller than the critical angle. Another part of the light waves impinging on the interface plane have incidence angles higher than the critical angle. The interface plane is substantially transparent for the light waves impinging on interface plane having incidence angles smaller than the critical angle.

A light emitting module includes a light guide plate including a first face, a second face opposing the first face, and a through part penetrating between the first face and the second face, a light emitting device disposed in the through part on a second face side, a light transmissive member disposed on the light emitting device in the through hole on a first face side and between the light emitting device and a lateral wall of the through part, and a first light reflecting member disposed between an upper face of the light emitting device and the light transmissive member while being in contact with the upper face of the light emitting device.

A backlight module includes a light guide plate, a light source, multiple first optical microstructures, and multiple second optical microstructures. The first optical microstructures and the second optical microstructures are disposed on the bottom surface of the light guide plate. Each of the first optical microstructures has a first light receiving surface facing the light source.

Each of the second optical microstructures has a second light receiving surface facing the light source. A first angle is included between the first light receiving surface and the bottom surface. A second angle is included between the second light receiving surface and the bottom surface. The second angle is different from the first angle. A display apparatus adopting the backlight module is also provided.

A device is provided. The device includes a light guide having a curved surface. The device also includes an out-coupling element coupled with the light guide at an output portion of the light guide. The device further includes a reflective layer disposed at the output portion of the light guide. The out-coupling element is configured to couple a first ray propagating inside the light guide out of the light guide as a plurality of second rays propagating in non-parallel directions toward the reflective layer. The reflective layer is configured to reflect the plurality of second rays as a plurality of third rays propagating in parallel directions toward the out-coupling element and the light guide.

An illumination device includes a plurality of light-emitting elements (LEEs); a light guide extending in a forward direction from a first end to a second end to receive at the first end light emitted by the LEEs and to guide the received light to the second end; an optical extractor optically coupled to the second end to receive the guided light, the optical extractor including a redirecting surface to reflect a first portion of the guided light, the reflected light being output by the optical extractor in a backward angular range, and the redirecting surface having one or more transmissive portions to transmit a second portion of the guided light in the forward direction; and one or more optical elements optically coupled to the transmissive portions, the optical elements to modify the light transmitted through the transmissive portions and to output the modified light in a forward angular range.

A backlight module includes a cover plate, a light guide plate, a circuit board, a reflective layer, and a light source. The light guide plate is disposed under the cover plate and has a first hole corresponding to a light-shielding region of the cover plate. The circuit board is disposed under the light guide plate and includes a first substrate and a conductive layer having a through hole. The reflective layer is disposed between the light guide plate and the circuit board and has a second hole. The first substrate is in contact with the reflective layer. The conductive layer is disposed between the first substrate and the reflective layer having a recess recessed into the through hole. The light source is disposed on the circuit board, accommodated in the first hole and the second hole corresponding thereto, and in contact with the conductive layer.

According to the invention, a light guide plate-type video display device and a video display system that are capable of displaying a video with less color deviation and less video distortion are provided. A video display device 101 configured to display a video includes a video projection unit 200 configured to project video light, a video deflection unit 210, and a light guide portion 230. The video deflection unit 210 deflects video light emitted by the video projection unit 200 and causes the video light to propagate to the light guide portion 230, and the light guide portion 230 causes the entered video light to propagate therein and outputs the video light. Here, the video deflection unit 210 or the light guide portion 230 is configured to reduce color dispersion of the video light outputted from the light guide portion 230.

An image projection system includes a cascaded waveguide system including a first waveguide and a second waveguide arranged downstream along a transmission path from the first waveguide. The first waveguide includes a first output structure and is configured to receive a light beam having a first beam width and output a first expanded light beam at the first output structure, wherein the first expanded light beam has a second beam width greater than the first beam width. The second waveguide includes a second output structure and is configured to receive the first expanded light beam from the first waveguide and output the first expanded light beam multiple times from the second output structure as a plurality of output light beams. Each of the plurality of output light beams is output from a different area of the second output structure along a propagation direction of the second waveguide.

A display apparatus including a display panel, a light source unit configured to provide light to the display panel, and a light guide member disposed between the display panel and the light source unit and covering the light source unit such that the light source unit is buried in the light guide member, the light guide member having a surface roughness on an upper surface thereof to diffuse light and including a substrate, and a light emitting device disposed on the substrate and including a blocking pattern to have an intensity of light emitted in an upward direction to be equal to or less than about 80% of a maximum light intensity of the light emitting device.