Abstract: A light shuttering device comprises a plurality of liquid crystal cells, wherein each liquid crystal cell is operable in a first optical state or a second optical state in response to a respective first or second drive signal. A drive circuit comprises a plurality of switches and a drive controller. Each switch is arranged to output the respective first or second drive signal to a respective liquid crystal cell. The drive controller is arranged to sequentially update the output of each switch during an update cycle. The drive circuit is arranged to determine the order in which the switches are sequentially updated during an update cycle based on any changes to the respective drive signals that will be made during the update.

Abstract: A light engine arranged to form an image visible from a viewing window. The light engine comprises: a display device arranged to display a hologram of the image and spatially modulate light in accordance with the hologram; a hologram replicator arranged to receive the spatially modulated light and provide a plurality of different light propagation paths for the spatially modulated light from the display device to the viewing window; and a control device disposed in an optical path between the first replicator and the second replicator. The control device is angled such that light from the first replicator is incident at an acute angle on the control device, and each cell of the array is switchable between a first state and a second state.

Abstract: A method of light detection and ranging comprises a displaying a first hologram of a first light pattern on a first array of light-modulating pixels and illuminating the first hologram with first pulsed light in order to project the first light pattern onto the scene. The method comprises a displaying a second hologram of a second light pattern on a second array of light-modulating pixels and illuminating the second hologram with second pulsed light in order to project the second light pattern onto the scene. At least one pulse property of the first pulsed light is different to that of the second pulsed light.

Abstract: A LIDAR system comprises a spatial light modulator for displaying a diffractive pattern comprising a hologram of a structured light pattern that is projected onto a scene. The structured light pattern comprises an array of light spots and a light source for illuminating the diffractive pattern to form a holographic reconstruction of the light pattern. A detection subsystem comprises light detection elements that detect light from a respective individual field of view (FOV) of the scene and output a respective detected light signal. A first subset of the individual FOVs are illuminated by a light spot of the light pattern and a second subset are not illuminated by the light spot. The system comprises a processor for identifying noise in a first detected light signal, relating to an individual FOV of the first subset, using a second detected light signal, relating to an individual FOV of the second subset.

Abstract: A LIDAR system for scene surveying comprises a spatial light modulator for displaying a diffractive pattern comprising a hologram of a light footprint, and a light source for illuminating the diffractive pattern to form a holographic reconstruction of the light footprint on a holographic replay plane in the scene. The light footprint comprises an array of light features. The system comprises a display driver for controlling the spatial light modulator and changing the diffractive pattern with time. The diffractive pattern is changed with time such that each light feature of the array of light features scans a respective sub-area of the scene. The system comprises a detection system having a plurality of light detecting elements and that is configured such that each light detecting element detects light from a respective individual field of view within the scene. Each sub-area of the scene contains a plurality of individual fields of view.

Abstract: A method for light detection and ranging comprises a forming a first light pattern within a region of a scene by holographic projection. The first light pattern comprises n light spots arranged in a regular array. A light return signal is received from each light detection element of an array of light detection elements directed at the region of the scene. The intensity of the light return signals is assessed. If the light return signals do not meet at least one signal validation criterion, a second light pattern is formed within the region of the scene by holographic projection. The second light pattern comprises m light spots arranged in a regular array, wherein m ? n. A time-of-flight in association with each light spot of the second light pattern is then determined.

Abstract: An optical system and a method of calculating a hologram of a virtual image for the optical system is described. The optical system comprises a display device arranged to display the hologram and a waveguide arranged to replicate the hologram. The method comprises determining a sub-hologram of a virtual image point within an area defined by straight line paths from the virtual image point to the perimeter of an entrance pupil of a viewer. The area comprises at least part of a virtual replica of the display device formed by the waveguide.

Abstract: A waveguide arranged as a pupil expander for a display system is disclosed. The waveguide comprises a pair of opposing surfaces arranged to guide a light field therebetween by internal reflection. An input port is arranged to receive light from the display system. A reflective element is arranged to internally reflect the light field. The input port and reflective element are formed on a second surface of the pair of opposing surfaces. An output port is formed on a first surface of the pair of opposing surfaces by a transmissive-reflective element configured to divide the light field at each internal reflection therefrom such that a plurality of replicas of the light field are transmitted out of the waveguide through the output port.

Abstract: A display system comprises a waveguide forming a pupil expander. The waveguide comprises a pair of opposing surfaces arranged to guide a diffracted light field therebetween by internal reflection. An input port of the waveguide is arranged to receive light from a display system. An output port of the waveguide is formed by a first transmissive-reflective element of a first surface of the pair of opposing surfaces. The first transmissive-reflective element is such that the diffracted light field is divided at each internal reflection and a plurality of replicas of the diffracted light field are transmitted out of the waveguide through the output port. The input port comprises a second transmissive-reflection element arranged to receive at least a portion of the light from the display system.

Abstract: A projection system arranged to receive an image for projection. The image is a colour image comprising a first colour component and a second colour component. The system is arranged to calculate a first hologram of the first colour component and a second hologram of the second colour component. The system is further arranged to add content of the second colour component to the first colour component before calculating the first hologram. The first hologram contains information of the first colour component and information of at least a portion of the second colour component. The system is further arranged to form a first holographic reconstruction by illuminating the first hologram with first colour light and to form a second holographic reconstruction by illuminating the second hologram with second colour light. The first holographic reconstruction changes the chromaticity of the at least a portion of the second colour component.

Abstract: Systems and methods disclosed herein include, among other aspects, a head-up display comprising an eye-box having a first dimension and a second dimension, where the head-up display is arranged to form first image content in a first image area at a first image area distance from the eye-box and second image content in a second image area at a second image area distance from the eye-box, where the first image area distance is less than the second image area distance and the first image area is at least partially overlapping in the first dimension with the second image area, and where the second image area extends less far in angular space than the first image area in at least one direction of the first dimension.

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: 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: 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: Systems and methods of determining a hologram of an image for a system comprising a display device and viewing system are disclosed. Some embodiments implement a multi-stage procedure comprising (i) determining a first complex light field at an entrance pupil of the viewing system, (ii) determining a second complex light field at a sensor plane of a sensor of the viewing system, (iii) determining a third complex light field at the entrance pupil, and (iv) determining a fourth complex light field at the display plane. Some embodiments include extracting a hologram from a data set corresponding to the fourth complex light field.

Abstract: 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.

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: 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 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.