Abstract: There is disclosed herein a waveguide comprising an optical slab and an optical wedge. The optical slab has a first refractive index, n1>1. The optical slab comprises: a pair of opposing surfaces and an input port. The pair of opposing surfaces are arranged in a parallel configuration. The input port is arranged to receive light into the optical slab at an angle such that the light is guided between the first and second opposing surfaces by a series of internal reflections. The optical wedge has a second refractive index, n2, wherein 1<n2<n1. The optical wedge comprises a pair of opposing surfaces arranged in a wedge configuration. A first surface of the optical wedge abuts the second surface of the optical slab to form an interface that allows partial transmission of light guided by the optical slab into the optical wedge at a plurality of points along the interface such that the light is divided a plurality of times.

Abstract: A holographic image generation system including a spatial light modulator; a light source; a temporal modulator; a light sensor and a demodulator. The spatial light modulator has pixels. The light source illuminates the spatial light modulator. The temporal light modulator modulates an output intensity of the light source over time to encode holographic data representing a hologram. The light sensor is associated with a spatial light modulator and receives light from the light source and generates a signal representative of the output intensity of the light source. The demodulator is connected to the light sensor to receive the signal. The demodulator decodes the signal to obtain the holographic data. The demodulator is connected to the spatial light modulator to set the pixels of the spatial light modulator in accordance with the holographic data to display the hologram ready for illumination by the light source to form a holographic reconstruction.

Abstract: A display system (300) comprising an optical system and a processing system. The optical system comprising a spatial light modulator (380), a light source, a Fourier transform lens, a viewing system (320, 330) and a processing system. The spatial light modulator is arranged to display holographic data in the Fourier domain, illuminated by the light source. The Fourier transform lens is arranged to produce a 2D holographic reconstruction in the spatial domain (310) corresponding to the holographic data. The viewing system is arranged to produce a virtual image (350) of the 2D holographic reconstruction. The processing system is arranged to combine the Fourier domain data representative of a 2D image with Fourier domain data representative of a phase only lens to produce first holographic data, and provide the first holographic data to the optical system to produce a virtual image.

Abstract: 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.

Abstract: Disclosed embodiments include a head-up display for a vehicle comprising a first pupil replicator and second pupil replicator. The first pupil replicator extends in a first direction. The first pupil replicator is arranged to receive a holographic light field from a spatial light modulator having a pixel array defining a limiting aperture of the head-up display. A holographic light field is a complex light field spatially modulated in accordance with a hologram displayed on the spatial light modulator. The second pupil replicator extends in the first direction and in a second direction perpendicular to the first direction. The second pupil replicator comprises a first major surface forming an output and a second major surface parallel to the first major surface. The first pupil replicator is arranged within a planar layer substantially parallel and adjacent to the second major surface of the second pupil replicator.

Abstract: Disclosed embodiments include a display system comprising a first waveguide pupil expander comprising an input port, output port, a first pair of parallel surfaces, and a second pair of parallel surfaces. The first pair of parallel surfaces is orthogonal to the second pair of parallel surfaces and arranged to light guide a diffracted or diverging (e.g. holographic) light field from the input port to the output port by internal reflection therebetween. A first surface of the first pair of parallel surfaces is partially transmissive-reflective such that the light field is divided at each internal reflection and a plurality of replicas of the light field is transmitted through a region of the first surface that forms the output port. The second pair of parallel surfaces is also arranged to light guide the light field from the input port to the output port by at least one internal reflection.

Abstract: Systems and method disclosed herein include, among other features, receiving an image for display within a display area of a display system, determining a first image component of the image, calculating a hologram of the image, displaying the hologram on a display device and spatially modulating light in accordance with the displayed hologram, and propagating the spatially modulated light through a pupil expander arranged to provide a plurality of different light propagation paths for the spatially modulated light from the display device to the viewing area, wherein each light propagation path corresponds to a respective continuous region of the image owing to the angular distribution of light from the hologram.

Abstract: There is disclosed herein a display device comprising a picture generating unit, a waveguide pupil expander and a viewer-tracking system. The picture generating unit comprises a first display channel, a second display channel and a controller. The first display channel is arranged to output first spatially-modulated light of a first colour. The first spatially-modulated light corresponds to a first picture. The second display channel is arranged to output second spatially-modulated light of a second colour. The second spatially-modulated light corresponding to a second picture. The controller is arranged to drive the first display channel and second display channel. The waveguide pupil expander comprises a pair of parallel reflective surfaces. The waveguide pupil expander defines an input port and a viewing window. The input port is arranged to receive the first spatially-modulated light and the second spatially-modulated light.

Abstract: 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.

Abstract: There is disclosed herein a waveguide comprising an optical slab and an optical wedge. The optical slab has a first refractive index, n1>1. The optical slab comprises: a pair of opposing surfaces and an input port. The pair of opposing surfaces are arranged in a parallel configuration. The input port is arranged to receive light into the optical slab at an angle such that the light is guided between the first and second opposing surfaces by a series of internal reflections. The optical wedge has a second refractive index, n2, wherein 1<n2<n1. The optical wedge comprises a pair of opposing surfaces arranged in a wedge configuration. A first surface of the optical wedge abuts the second surface of the optical slab to form an interface that allows partial transmission of light guided by the optical slab into the optical wedge at a plurality of points along the interface such that the light is divided a plurality of times.

Abstract: A light engine arranged to form an image visible from a viewing window, the light engine comprising a display device for displaying a hologram of the image and spatially modulating light based on the hologram. The hologram is configured to angularly distribute spatially-modulated light of the image based on position of image content, where angular channels of the spatially-modulated light correspond with respective continuous regions of the image. The light engine further comprises a waveguide pupil expander for receiving the spatially-modulated light and providing a plurality of light propagation paths for the spatially-modulated light from the display device to the viewing window, and a control device between the waveguide and the viewing window. The control device comprises an aperture arranged such that a first viewing position receives a first channel of spatially-modulated light and a second viewing position receives a second channel of spatially-modulated light.

Abstract: A display system comprising a first plurality of pixels, a second plurality of pixels, a first Fourier transform lens and a second Fourier transform lens. The first plurality of pixels is arranged ranged to display first holographic data corresponding to a first holographic reconstruction and receive light of a first wavelength. The a second plurality of pixels is arranged to display second holographic data corresponding to a second holographic reconstruction and receive light of a second wavelength. The first Fourier transform lens is arranged to receive spatially modulated light having a first wavelength from the first plurality of pixels and perform an optical Fourier transform of the received light to form the first holographic reconstruction at a replay plane, wherein the first holographic reconstruction is formed of light at the first wavelength.

Abstract: A holographic projector having an optical path is described. The holographic projector comprises a first spatial light modulator arranged to display a first hologram, and a first light source. The first light source is arranged to illuminate the first spatial light modulator with light of a first wavelength such that a first holographic reconstruction corresponding to the first hologram is formed on a replay plane. The holographic projector further comprises a continuous block of transparent material. At least part of the optical path is formed through the continuous block of transparent material. The transparent material has a refractive index greater than air.

Abstract: A method of calculating a hologram having an amplitude and a phase component. The method comprises (i) receiving an input image comprising a plurality of data values representing amplitude. The method then comprises (ii) assigning a random phase value to each data value of the plurality of data values to form a complex data set. The method then comprises (iii) performing an inverse Fourier transform of the complex data set. The method then comprises (iv) constraining each complex data value (X1, X2) of the transformed complex data set to one of a plurality of allowable complex data values (GL1-GL8), each comprising an amplitude modulation value and a phase modulation value, to form a hologram, wherein, the phase modulation values (GL1-GL7) of the plurality of allowable complex data values substantially span at least 3?/2 and at least one of the allowable complex data values has an amplitude modulation value of substantially zero (GL8) and a phase modulation value of substantially zero.

Abstract: A head-up display arranged to form a virtual image viewable from an eye-box area. The head-up display is arranged to received picture content within a sub-region of a substantially quadrilateral display area. The head-up display further comprises an optical relay system arranged to relay the received picture content to an eye-box of the head-up display such that a virtual image of the picture content is visible therefrom. The optical relay system comprises at least one optical component shaped in correspondence with the shape of the sub-region. The shape of the eye-box area is non-rectangular such as a corner-cropped rectangular shape or elliptical shape.

Abstract: Display system and methods including a display device arranged to display a hologram and spatially modulate light and a hologram engine arranged to receive contribution information identifying contributory and non-contributory areas of the display device based on the location of an entrance pupil. The contributory areas of the display device propagate light passing through the entrance pupil at the determined location. The non-contributory areas of the display device propagate light stopped by the entrance pupil at the determined location. The contribution information identifies (i) at least one primary contributory area of the display device that contributes to a primary image and (ii) at least one secondary contributory area of the display device that contributes to a secondary image. The hologram engine is arranged to determine a hologram based on the at least one primary contributory area of the display device identified by the processing engine.

Abstract: A holographic projector includes a spatial light modulator, a light receiving member and a driver. The spatial light modulator is arranged to receive and represent a computer-generated hologram and spatially modulate light incident on the spatial light modulator to form a holographic reconstruction in accordance with the computer-generated hologram. The light receiving member is arranged to receive spatially modulated light along an optical axis from the spatial light modulator and the holographic reconstruction is formed on the light receiving member. The driver is coupled to the light receiving member to move the light receiving member in a plane. The driver is configured to move the light receiving member while maintaining an orientation of the light receiving member relative to the spatial light modulator substantially constant.

Abstract: A head-up display for a vehicle having a window. The head-up display comprises a picture generating unit and a projection engine. The picture generating unit is arranged to output pictures. Each picture comprises a first picture component and a second picture component. The projection engine is arranged to receive the pictures output by the picture generating unit and project the pictures onto the window of the vehicle in order to form a first virtual image of the first picture component at a first virtual image distance and a second virtual image of the second picture component at a second virtual image distance. Light of the first picture component is polarised in a first polarisation direction and light of the second picture component is polarised in a second polarisation direction perpendicular to the first polarisation direction.

Abstract: There is provided a head-up display for a vehicle. The head-up display has a first housing and a second housing. The first housing comprises a picture generating unit and optical system. The second housing comprises a substantially flat cover glass and a layer. The picture generating unit is arranged to output pictures. The picture generating unit comprises a light source and a spatial light modulator. The light source is arranged to emit light. The spatial light modulator is arranged to receive the light from the light source and spatially-modulate the light in accordance with computer-generated light-modulation patterns displayed on the spatial light modulator to form a holographic reconstruction corresponding to each picture. The optical system is arranged to receive the pictures output by the picture generating unit and relay the pictures using an optical combiner to form a virtual image of each picture.

Abstract: There is disclosed a projector arranged to project a light pattern. The projector comprises a spatial light modulator and a light source. The spatial light modulator has an array of pixels arranged to display a phase pattern. The array of pixels may be a substantially planar array of pixels. Each pixel comprises liquid crystals having a director rotatable in a plane of rotation between a first direction and a second direction. The light source is arranged to illuminate the array of pixels with polarised light such that the light is spatially-modulated in accordance with the phase pattern to form the light pattern. It may be said that the light pattern corresponds to the phase pattern. The angle of incidence of the light on the array of pixels is greater than zero and the light is s-polarised. The first direction is parallel to the polarisation direction of the light. The second direction is in the plane of incidence.