A diffractive optical element exerts a diffractive action on a display light that is emitted from a display unit. A folding mirror is provided on the opposite side of the diffractive optical element from the display unit to reflect the display light. The diffractive optical element includes a transmissive action part and a diffractive and reflective action part. The transmissive action part exerts a transmissive action to transmit therethrough the display light, which is incident from the display unit and is in a first polarization state, toward the folding mirror. The diffractive and reflective action part exerts a diffractive and reflective action to diffract and reflect the display light, which is reflected by the folding mirror and is in a second polarization state opposite to the first polarization state, toward the projection portion on an optical path.

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.

It is an objective of this disclosure to protect a highly transparent hologram light guide plate from water vapor and ultraviolet ray, thereby suppressing deterioration of the hologram light guide plate even when employed in a head mount display used in outdoor environments. A hologram light guide plate according to this disclosure comprises a protection layer that protects a hologram layer and an intermediate layer that is placed between a glass layer and the protection layer, wherein the glass layer and the hologram layer form a transfer layer that transfers image light. The intermediate layer causes the image light to transfer only in the transfer layer in a section from an input area of the image light to an output area of the image light.

Provided a display apparatus including an image forming apparatus configured to form an image, a projection optical system configured to project the image formed by the image forming apparatus, and a combining optical system configured to provide the image projected from the projection optical system combined with light emitted from an external landscape, wherein the combining optical system is configured to divide the image projected from the projection optical system into same images and focus the same images on different positions.

A head-up display is described. A spatial light modulator is arranged to display a diffractive pattern of first picture content and/or second picture content. A screen assembly has first and second diffusers arranged in a stepped configuration so that the first diffuser is spatially offset from the second diffuser by a perpendicular distance. A light source is arranged to illuminate the diffractive pattern such that the first picture content is formed on the first diffuser and/or the second picture content is formed on the second diffuser. An optical system comprising at least one optical element having optical power is arranged so that the first and second diffusers have different object distances to the optical system.

There are provided a linearly polarized light reflection film that has a high visible light transmittance, is capable of increasing the brightness of a display image, and is highly transparent in terms of appearance tint, a windshield glass, and a head-up display system. The linearly polarized light reflection film has a selectively reflecting layer in which an optically anisotropic layer and an isotropic layer are laminated. The selectively reflecting layer has at least one first reflection peak having a reflection center wavelength of 430 nm or more and less than 500 nm and having a reflectivity of 10% or more and 20% or less, at least one second reflection peak having a reflection center wavelength of 530 nm or more and less than 600 nm and having a reflectivity of 10% or more and 20% or less, and a third reflection peak having a reflection center wavelength of 600 nm or more and 800 nm or less, where two or more reflection peaks are present with a reflectivity of 10% or more and 20% or less or one reflection peak is present with a reflectivity of 10% or more and 20% or less and a wavelength width of 120 nm or more.

Provided a display apparatus including an image forming apparatus configured to form an image, a projection optical system configured to project the image formed by the image forming apparatus, and a combining optical system configured to provide the image projected from the projection optical system combined with light emitted from an external landscape, wherein the combining optical system is configured to divide the image projected from the projection optical system into same images and focus the same images on different positions.

In one aspect, an optical system is disclosed. In some embodiments, the optical system includes an optical waveguide, and at least two coupling means forming at least one confocal point being located within the optical waveguide, where a first coupling means of the at least two coupling means has a first focal length, and a second coupling means of the at least two coupling means has a second focal length. In some examples, the first coupling means is configured to couple and/or focus incident light to the optical waveguide, and the second coupling means is configured to emit and/or collimate light conveyed by the optical waveguide.

An optical system for displaying a virtual image to a viewer includes stacked integral first reflective polarizer and integral second reflective polarizer, a display, and a mirror. For substantially normally incident light: for at least one visible wavelength in a first wavelength range, the first reflective polarizer reflects at least 60% of the incident light having a first polarization state and transmits at least 60% of the incident light having an orthogonal second polarization state, and the second reflective polarizer transmits at least 60% of the incident light for each of the first and second polarization states; and for at least one infrared wavelength in a second wavelength range, the first reflective polarizer reflects at least 60% of the incident light having the first polarization state and transmits at least 60% of the incident light having the second polarization state, and the second reflective polarizer reflects at least 60% of the incident light having the second polarization state and transmits at least 20% of the light having the first polarization state.

An optical assembly is provided for use in holographic display of a replay image. The optical assembly may be of particular use is an augmented reality headset. The optical assembly includes a light-modulation element arranged to be illuminated off-axis by a light beam. The light-modulation element modulates the incident light to generate a replay image and generates a zero-order light beam. A focusing system is arranged after the light-modulation element. A light remover is positioned after the focussing system and is configured to remove the zero-order light beam from the light focussed by the focussing system. The focussing system is configured to focus zero-order light from the light-modulation element in a first plane different from a second plane which is the plane of focus of parallel light of the replay image. The light remover removes the zero-order light in the first plane.