Disclosed is an improved diffraction structure for 3D display systems. The improved diffraction structure includes an intermediate layer that resides between a waveguide substrate and a top grating surface. The top grating surface comprises a first material that corresponds to a first refractive index value, the underlayer comprises a second material that corresponds to a second refractive index value, and the substrate comprises a third material that corresponds to a third refractive index value.

The invention relates to a handheld device and method for determining a status of a plant. The device includes a multi pixel digital colour sensor, a light source arranged for providing broadband illumination, wherein the light source and the multi pixel digital colour sensor are arranged in substantially the same plane, a light guide for guiding the light from said light source into the direction of the multi pixel digital colour sensor, a sample space, provided between the multi pixel digital colour sensor and the light source, for insertion of at least a part of the plant therein, and a processing unit configured for controlling at least the multi pixel digital colour sensor and the light source.

According to one embodiment, a display device includes a first display panel including a first and second transparent substrate, a first liquid crystal layer, and a first light-emitting element, a second display panel including a third and fourth transparent substrate, a second liquid crystal layer and a second light emitting element, a filling member provided between the first and second display panel and having a refractive index equal to that of the first to fourth transparent substrates, a first light guide bonded to the first and second display panel, and a first adhesive member provided between the first display panel and the first light guide and between the second display panel and the first light guide.

Diffraction gratings provide optical elements in head-mounted display systems to, e.g., incouple light into or out-couple light out of a waveguide. These diffraction gratings may be configured to have reduced polarization sensitivity. Such gratings may, for example, incouple or outcouple light of different polarizations with similar level of efficiency. The diffraction gratings and waveguides may include a transmissive layer and a metal layer. The diffraction grating may comprises a blazed grating.

A system and method includes a display device comprising a spatial light modulator arranged to output spatially modulated light to form an image. The system further includes a waveguide pupil expander configured to receive spatially modulated light from the display device at an input port thereof and to expand the viewing window of the system. The system further comprises a controller. In examples, the controller is configured to control the spatially modulated light output by the display device, such as to control (e.g., turn off) a light source of the display device, in response to a signal indicating detection of the breakage of glass. The signal indicating detection of the breakage of glass may be generated in response to the detection of stray laser light of the holographic system by an eye-tracking system.

Provided is a display module, including: a shell; a display panel, wherein the display panel is disposed in the shell and is connected to the shell; a first light emitting component, wherein the first light emitting component is connected to the display panel and is configured to emit light of a target wavelength; and a fingerprint recognition sensor, wherein the fingerprint recognition sensor is disposed between the shell and the display panel and is fixedly connected to the shell; an orthographic projection of the fingerprint recognition sensor onto the display panel and an orthographic projection of the first light emitting component onto the display panel do not overlap; and the fingerprint recognition sensor is configured to recognize a fingerprint based on received light of the target wavelength reflected by an obstacle.

A device and method for providing diffuse emission of light through a flat surface, which includes a flat light guide having two larger flat surfaces on opposite sides and side surfaces, wherein one of the two larger flat surfaces being a light emitting surface and the other surface being a back surface, a connector for coupling light into said flat light guide, and a diffusing layer arranged in contact with at least one of said two larger flat surfaces of said flat light guide.

An optoelectronic device includes a substrate and at least three emitters, which are disposed on the substrate and are configured to emit respective beams of light. A plurality of waveguides are disposed on the substrate and have respective input ends coupled to receive the beams of light from respective ones of the emitters, and curve adiabatically from the input ends to respective output ends of the waveguides, which are arranged on the substrate in an array having a predefined pitch. Control circuitry is configured to apply a temporal modulation independently to each of the beams of light.

The head-mounted display includes: an image display unit that generates an image to be displayed; and a first light guide plate and a second light guide plate which duplicate image light from the image display unit. Each of the first light guide plate and the second light guide plate includes a set of parallel main surfaces confining the image light with internal reflection, the first light guide plate includes an incident plane that reflects the image light to an inner side, and two or more emission/reflection planes from which the image light is emitted to the second light guide plate, the second light guide plate includes an input part that couples the image light transmitted from the first light guide plate to the inner side, and an output part from which the image light is emitted to a user’s pupil.

The invention discloses a three-dimensional display module using optical wave-guide for providing directional backlights. This display module includes a wave-guide backlight unit with time-sequential directional light sources, a display device, a wavefront modulation device or a light splitting device, and other components. The wave-guide backlight unit with time-sequential directional light sources includes a sequential-switching light-source array, a relay device, and an optical wave-guide device. Each light source of the sequential-switching light-source array provides backlight of corresponding vector characteristics to the display device, making optical message displayed by the display device being guided to the corresponding viewing zone/viewing zones. Through the technology routes of multiple-view-for-one-pupil or/and Maxwellian view, the three-dimensional display module implements displays free from the vergence-accommodation conflict. The introduction of the optical wave-guide device results in a thin structure, and the disclosed display module can be applied to various display terminals, such as mobile phones, iPads, head-mounted VR/AR, etc.