An imaging apparatus for conveying a virtual image including a waveguide having first and second surfaces. An in-coupling diffractive optic and an out-coupling diffractive optic arranged along one of the first and second surfaces, wherein the in-coupling diffractive optic is operable to direct image-bearing light beams into the waveguide for propagation by total internal reflection, and wherein the out-coupling diffractive optic is operable to direct at least a portion of the image-bearing light beams from the waveguide through the second surface toward an eyebox. An at least partially transparent outer cover located adjacent to the first surface, and a circular polarizer arranged between the waveguide and the outer cover, wherein the circular polarizer is operable to circularly polarize at least a portion of image-bearing light beams transmitted through the first surface and to prevent at least a portion of image-bearing light beams transmitted through the first surface from reentering the waveguide as a result of reflection from the outer cover.

An optical device for illuminating one or more portions of a spatial light modulator includes a waveguide, an array of tunable retarders, and a polarization selective optical element. A respective tunable retarder is optically coupled to receive light from the waveguide. The respective tunable retarder has a first state, which causes the respective tunable retarder to direct light having a first polarization in a first direction, and a second state, which causes the respective tunable retarder to direct light having a second polarization distinct from the first polarization in the first direction. The polarization selective optical element is located adjacent to the array of tunable retarders so that the light having the first polarization propagates from the polarization selective optical element in a second direction and the light having the second polarization propagates from the polarization selective optical element in a third direction distinct from the second direction.

An optical element which can be utilized in various versions and implementations of switchable light filters having, in addition, polarization filters and/or other means for varying the polarization characteristics of light, for example, liquid crystal layers. A combination of switchable light filter and imaging display device makes possible a private viewing effect that can be switched on and off. The optical element comprises a first layer or a first layer and a plurality of further layers, each layer including a material with a plurality of light-absorbing transition dipole moments. At least in a first state, each transition dipole moment is oriented, with a tolerance of 10° at the maximum, parallel to a selectable preferential direction or fluctuates around it so that light which is incident in the optical element is transmitted or at least partially absorbed depending on its incident direction.

A method and system for reducing the effects of glare in a system comprising a picture generating unit, such as a holographic projector. The system may be a head-up display (HUD), which is configured to display a picture to a viewer, without requiring the user to look away from their usual viewpoint. The HUD system may be comprised within a vehicle. The glare in the system may be caused by light being incident on a surface comprising a screen or a window, through which the user looks at their usual viewpoint. The surface may comprise a windshield in a vehicle. The light that causes the glare may be ambient light. The method and system are provided for reducing the effects of glare in a system that comprises a waveguide in conjunction with the picture generating unit. The waveguide may be operable to act as an exit pupil expander.

An optical device for providing illumination light includes an optical waveguide and a plurality of polarization selective elements. The plurality of polarization selective elements is disposed adjacent to the optical waveguide so that a respective polarization selective element receives light in a first direction, and redirects a first portion of the light in a second direction. A second portion, distinct from the first portion, of the light undergoes total internal reflection, thereby continuing to propagate inside the optical waveguide.

An optical device includes a stack of multiple grating structures, each of which includes a plurality of sublayers of liquid crystal material. Each sublayer of liquid crystal material includes laterally extending repeating units, each formed of a plurality of liquid crystal molecules. The repeating units of the liquid crystal layers are lateral offset from one another, and defined a tilt angle. The grating structures forming the stack of grating structure have tilt angles of different magnitudes. The grating structures may be configured to redirect light of visible or infrared wavelengths. Advantageously, the different tilt angles of the stack of grating structures allows for highly efficient diffraction of light incident on the grating structures at a wide range of incident angles.

The invention relates to a head-up display device, a vehicle comprising such device and a method of forming an image in a head-up display device. The head-up display device is adapted to project an image on an image surface, such as a windshield. The device comprises a waveguide capable of guiding light carrying the image to be displayed, and an optical correction element. According to the invention, the waveguide is configured to couple light propagating therein towards the optical correction element, and the optical correction element is further configured to perform an optical function for said light and to direct the light towards the image surface through the waveguide.

Provided is a light absorption anisotropic layer including a dichroic substance, in which a transmittance as viewed from a front direction is high and a transmittance as viewed from an oblique direction can be lowered, a laminate, an optical film, an image display device, and a backlight module. The light absorption anisotropic layer includes a liquid crystalline compound and at least one dichroic substance, in which the dichroic substance is aligned perpendicular to the film surface, and an alignment degree of the light absorption anisotropic layer at a wavelength of 550 nm is 0.95 or more.

A switchable directional backlight for a privacy display comprises a waveguide with first and second opposing input ends and a turning film arranged to collect light output from the waveguide for input into a spatial light modulator. The waveguide has an array of light deflecting features arranged on one guiding surface and an opposing planar surface. Light deflecting features are arranged such that light input from the first input end is output with a narrow angular range and light input from the second input end is output with a wide angular range.

An image source unit includes: a surface light source device including a reflective polarizing plate; a liquid crystal panel; and an optical sheet that is arranged between the surface light source device and the liquid crystal panel, the optical sheet including: an optical function layer that is laminated to one surface of a substrate layer; and a light diffuser layer that is arranged on one surface of the optical function layer, the one surface being on an opposite side of another surface of the optical function layer where the substrate layer is arranged across the optical function layer, the optical function layer including: light transmission parts that extend in a horizontal direction, and are arranged in a plurality of rows at predetermined intervals in a vertical direction; and light absorption parts that are formed between adjacent light transmission parts, and have a lower refractive index than that of the light transmission parts, wherein an angle formed by interfaces on upper sides of the light absorption parts and a normal line of a surface of the optical sheet is narrower than that formed by the interfaces on lower sides of the light absorption parts and the normal line of the surface of the optical sheet.