Devices, systems and methods that include specialized waveguide assemblies are provided for performing light transformations. Some waveguide assemblies include a waveguide and a compensating lens. The waveguide includes a front surface and a back surface, wherein the waveguide is configured to receive external light at the front surface and transmit the external light through the waveguide to the back surface. The compensating lens is located on the back surface and is configured to direct light emitted from the back surface toward an exit pupil proximate the back surface. The compensating lens has an input surface oriented toward the waveguide and an opposing output surface oriented away from the waveguide. The waveguide can sometimes increase a user's field of view with minimal distortion on a mixed reality display.

In a stacked waveguide assembly, the waveguides can comprise color filters, distributed filters, and/or switch materials. Examples of color filters include dyes, tints, or stains. Examples of distributed filters and/or switch materials include dichroic filters, Bragg gratings, electronically switchable glass, and electronically switchable mirrors. Switch materials can be designed or tuned to attenuate light of unwanted colors or wavelengths. The waveguides may each be associated with a particular design wavelength. This can mean that a waveguide that is associated with a design wavelength includes an incoupling optical element is configured to deflect light at the design wavelength to an associated light distributing element and that the associated wavelength selective region is configured to attenuate light not at the design wavelength.

A display apparatus includes a waveguide; an input coupler on the waveguide and configured to introduce light containing an image into the waveguide; and an output coupler on the waveguide and configured to output light traveling in the waveguide to the outside of the waveguide, wherein the output coupler includes a plurality of first diffraction grating elements arranged apart from each other and configured to diffract a first light portion in a first wavelength band among the light traveling in the waveguide.

A backlight unit for a binocular-holographic display device and a holographic display device including the same are provided. The backlight unit includes a light source unit which outputs light, a first beam expansion unit which expands, in a first direction, the light output from the light source unit, a second beam expansion unit which expands, in a second direction perpendicular to the first direction, the light output from the first beam expansion unit, and a beam deflection unit which diffracts light incident on the first beam expansion unit. The holographic display device includes the backlight unit, a field lens, and a spatial light modulator.

A backlight module and display device are provided. The backlight module includes: a light source module including a transparent block, a light source and a first grating group, and a light emergent module including a light guide plate and a second grating group. The light source emits initial lights to the first grating group which diffracts initial into first diffracted lights, and transmits first diffracted lights in light guide plate to second grating group; the second grating group diffracts the first diffracted lights into second diffracted lights, and enables the second diffracted lights to be emergent from backlight module. When an included angle between initial lights and side surface of light guide plate is greater than 0°, an angle between second diffracted lights and side surface is smaller than an angle between initial lights and side surface, thereby improving collimation degree of lights emergent from backlight module.

The present disclosure relates to a holographic display device and an electronic device. The holographic display device may include a light source, a light transmission structure, a first photonic crystal group, and a spatial light modulator. The light transmission structure has a light incident surface and a light exiting surface. The first photonic crystal group is disposed between the light incident surface and the light source. The first photonic crystal group includes various photonic crystals for dividing light emitted by the light source into light beams of different colors. The light beams of different colors are transmitted into the light transmission structure through the light incident surface and emitted through the light exiting surface. The spatial light modulator corresponds to the light exiting surface for modulating light beams of different colors emitted from the light exiting surface to form a holographic image.

Briefly, in one aspect, the present invention relates to processes for producing a stabilized Mn.sup.4+ doped phosphor in solid form and a composition containing such doped phosphor. Such process may include combining a) a solution comprising at least one substance selected from the group consisting of: K.sub.2HPO.sub.4, an aluminum phosphate, oxalic acid, phosphoric acid, a surfactant, a chelating agent, or a combination thereof, with b) a Mn.sup.4+ doped phosphor of formula I in solid form, where formula I may be: A.sub.x [MF.sub.y]:Mn.sup.4+. The process can further include isolating the stabilized Mn.sup.4+ doped phosphor in solid form. In formula I, A may be Li, Na, K, Rb, Cs, or a combination thereof. In formula I, M may be Si, Ge, Sn, Ti, Zr, Al, Ga, In, Sc, Y, La, Nb, Ta, Bi, Gd, or a combination thereof. In formula I, x is the absolute value of the charge of the [MF.sub.y] ion and y is 5, 6 or 7.

Subject matter disclosed herein relates to arrangements and techniques that provide for using a wavelength specific illumination for illuminating a display, for example an electrowetting display. The electrowetting display comprises a first substrate and a second substrate. A plurality of pixel regions is provided between the first substrate and the second substrate. The electrowetting display further comprises a first fluid within the pixel regions and on the first substrate. The first fluid comprises one or more dyes and a second fluid is disposed on the first fluid. The second fluid is substantially immiscible with the first fluid. An illumination layer is included between the first substrate and the second substrate. The illumination layer comprises one or more LEDs and at least one of the LEDs produces light at a specific wavelength corresponding to a wavelength of absorption of one of the one or more dyes.

To provide a wavelength converting member in which the occurrence of blackening can be suppressed compared to the prior art; and a light emitting device, a light emitting element, a light source unit, and a display device using the wavelength converting member. The wavelength converting member includes: a receptacle including a light entrance plane and a light exit plane opposite to the light entrance plane and provided with a receiving space inside the light entrance plane and the light exit plane; and a wavelength conversion layer having quantum dots that is placed in the receiving space. The distance between the light entrance plane and the wavelength conversion layer is longer than the distance between the light exit plane and the wavelength conversion layer.

A near eye or heads up display system includes a scan beam projector engine, an optical waveguide, and an exit pupil expander (EPE) optically coupled between the scan beam projector engine and the optical waveguide. The EPE improves the optical performance of the display system. The EPE could include a diffusive optical element, diffractive optical element, micro-lens array (MLA), or relay of aspherical lenses. A dual MLA EPE may have cells that prevent cross-talk between adjacent pixels. A dual MLA EPE may have a non-periodic lens array. The optical power of one MLA may be different from the other MLA.