Abstract: Various approaches related to capturing content of erasable boards are discussed herein.

Abstract: A method of capturing writing or drawing on a whiteboard comprises inputting camera data for a succession of image frames of the whiteboard, and processing data from said image frames to remove parts of the image frames corresponding to parts of a user or user pen writing or drawing on the whiteboard. The processing involves filtering to distinguish between i) motion of the user/user pen parts in the image frames, and ii) writing/drawing image information in the image frames which appears or changes during said writing or drawing but which is thereafter substantially unchanging. The filtered data defines captured writing or drawing from the whiteboard.

Abstract: Various approaches to touch sensing systems are disclosed As an example, a touch sensing system is disclosed that includes: an optical beam source to provide an optical beam; a pair of controllable beam deflectors comprising at least first and second beam deflectors, wherein the first beam deflector is configured to deflect the optical beam through a first angle towards a touch sensing region, and wherein the second beam deflector is configured to deflect scattered light from an object in the touch sensing region through a second angle; a detector, in particular a detector array; and an imaging system to image the deflected scattered light from the second beam deflector onto the detector array. The first and second beam deflectors are controlled in tandem to scan the touch sensing region.

Abstract: We describe a method of capturing writing or drawing on a whiteboard. The method comprises: inputting camera data for a succession of image frames, wherein the camera data is from a camera directed towards the whiteboard and the image frames comprise successive images of the whiteboard from the camera; and user filter processing data from said image frames to remove parts of said image frames corresponding to parts of a user or user pen writing or drawing on said whiteboard. The user-filter processing comprises filtering to distinguish between motion of the user/user pen parts in the image frames and writing/drawing image information in the image frames which appears or changes during said writing or drawing but which is thereafter substantially unchanging. The method outputs writing/drawing data from the user filter-processing, this defining captured writing or drawing from the whiteboard.

Abstract: We describe a touch sensing system comprising a light source to project light defining a touch sheet above a surface; a camera directed to capture a touch sense image from the touch sheet, comprising light scattered by an object; and a signal processor to process the touch sense image to identify a lateral location of the object on the surface. A brightness of the projected light is modulated to define bright, touch detecting intervals and dark intervals. The camera and the light projection are synchronized such that the camera selectively captures scattered light during the touch detecting intervals and rejects ambient light during the dark intervals. The system further comprises a pen. The pen comprises a photodetector to detect the projected light, a first light source detectable by the camera, and a controller coupled to control the first light source such that it is selectively illuminated during touch detecting intervals in synchronism with modulated projected light of the touch sheet.

Abstract: We describe a touch sensitive image display device for projecting a touch sensitive displayed image at an acute angle onto a surface on which the device is placed, the device comprising: a first light source to project a first light distribution; a second light source to project a second light distribution; a touch sensor system to remotely detect touch of an area of said surface within or adjacent to said displayed image by detecting change of said first light distribution, and having an output to provide a detected touch signal; a presence sensor system to remotely detect presence of an object at least partially within said second light distribution by detecting change of said second light distribution, and having an output to provide a detected presence signal; a controller configured to control said device responsive to said detected touch signal and further configured to control said device responsive to said detected presence signal.

Abstract: We describe a touch sensitive image display device for projecting a touch sensitive displayed image at an acute angle onto a surface on which the device is placed. The device comprises: light sources to project two-dimensional first and second light distributions in respective first and second planes; and a multi-pixel sensor system to remotely detect touch of an area of said surface within or adjacent to the displayed image by detecting light from the first distribution to provide a detected touch signal. The multi-pixel sensor system also remotely detects presence of an object within the second light distribution to provide a detected presence signal. The device is configured to multiplex projection of the first light and second distributions. A controller has an input to receive the detected touch and detected presence signals and is configured to control the device responsive to these signals.

Abstract: A touch sensitive device, the device comprising: a touch sensor light source to project a plane of light above a surface: a camera directed to capture a touch sense image from a region including at least a portion of said plane of light, said touch sense image comprising light scattered from said plane of light by a plurality of said objects simultaneously approaching or touching said surface; a signal processor coupled to said camera, to process a said touch sense image from said camera to identify a lateral location of each of said objects; and an output object position output, to provide output object positions for said plurality of objects; and wherein said signal processor is further configured to: input a succession of said touch sense images; process each said touch sense image to identify a plurality of candidate object touch positions; and filter said candidate object touch positions from said successive touch sense images to link said candidate object touch positions to previously identified output

Abstract: We describe a touch sensitive image display device including: an image projector to project a displayed image onto a surface; a touch sensor light source to project a plane of light above the displayed image; a camera to capture a touch sense image from light scattered from the plane of light by an approaching object; and a signal processor to process the touch sense image to identify a location of the object. The touch sensor light source is amplitude modulated, and signal processor is further configured to process a plurality of the touch sense images captured when said touch sensor light source is off to compensate for ambient light in a touch sense image captured when the touch sensor light source is on.

Abstract: This invention relates to methods, apparatus, and computer program code for the holographic display of images. We describe a method of displaying an image holographically. The method includes displaying a hologram on pixels of a spatial light modulator (SLM) and illuminating the SLM such that the image is displayed in pixels of a replay field (RPF) of the hologram. The method further includes subdividing the replay field into a plurality of spatially interlaced regions, and displaying holograms for each of the interlaced regions of the replay field sequentially at different times such that in an observer's eye the interlaced regions integrate to give the impression of the image and such that interference between adjacent pixels of the replay field is reduced.

Abstract: We describe a touch sensitive holographic image display device for holographically projecting a touch sensitive image at an acute angle onto a surface on which the device is placed. The device includes holographic image projection optics comprising at least one coherent light source illuminating a spatial light modulator (SLM), output optics to project a hologram onto an acute angle surface, and a remote touch sensing system to remotely detect a touch of a location within or adjacent to the holographically displayed image. A control system is configured to provide data defining an image for display, to receive detected touch data, and to control the device responsive to remote detection of a touch of a the displayed image.

Abstract: We describe a touch sensitive holographic image display device for holographically projecting a touch sensitive image at an acute angle onto a surface on which the device is placed. The device includes holographic image projection optics comprising at least one coherent light source illuminating a spatial light modulator (SLM), output optics to project a hologram onto an acute angle surface, and a remote touch sensing system to remotely detect a touch of a location within or adjacent to the holographically displayed image. A control system is configured to provide data defining an image for display, to receive detected touch data, and to control the device responsive to remote detection of a touch of a the displayed image.

Abstract: This invention relates to holographic image display systems, and to related methods and processor control code. We describe a method of displaying an image holographically, the method including: inputting display image data defining said image for display; processing said image data to determine first image data representing a first spatial frequency portion of said image data and second image data representing a second spatial frequency portion of said image data, wherein said second spatial frequency is higher than said first spatial frequency; displaying a hologram of said first image data on a spatial light modulator (SLM) to form a holographically-generated intermediate real image; modulating said intermediate real image using said second image data to display said image.

Abstract: The invention relates to method, computer program code and signal processing/image display systems for displaying one or more images using holographic techniques. We describe a method of generating data for displaying an image defined by displayed image data using a plurality of holographically generated temporal subframes, the temporal subframes being displayed sequentially in time such that they are perceived as a single noise-reduced image. The method includes generating from the displayed image data holographic data for each subframe of said set of subframes such that successive replay of holograms defined by said holographic data for said subframes gives the appearance of said image, and wherein the method further includes, when generating said holographic data for a said subframe, compensating for noise in said displayed image arising from one or more previous subframes of said sequence of holographically generated subframes.

Abstract: We describe a road vehicle contact-analogue head up display (HUD) comprising: a laser-based virtual image generation system to provide a 2D virtual image; exit pupil expander optics to enlarge an eye box of the HUD; a system for sensing a lateral road position relative to the road vehicle and a vehicle pitch or horizon position; a symbol image generation system to generate symbology for the HUD; and an imagery processor coupled to the symbol image generation system, to the sensor system and to said virtual image generation system, to receive and process symbology image data to convert this to data defining a 2D image for display dependent on the sensed road position such that when viewed the virtual image appears to be at a substantially fixed position relative to said road; and wherein the virtual image is at a distance of at least 5 m from said viewer.

Abstract: This invention relates to holographic image display systems, and to related methods and processor control code. We describe a method of displaying an image holographically, the method including: inputting display image data defining said image for display; processing said image data to determine first image data representing a first spatial frequency portion of said image data and second image data representing a second spatial frequency portion of said image data, wherein said second spatial frequency is higher than said first spatial frequency; displaying a hologram of said first image data on a spatial light modulator (SLM) to form a holographically-generated intermediate real image; modulating said intermediate real image using said second image data to display said image.

Abstract: A holographic image projection system for projecting an image at an acute angle onto a surface includes: a spatial light modulator (SLM) to display a hologram; an illumination system to illuminate the displayed hologram; projection optics to project light from the illuminated displayed hologram onto the surface at an acute angle form the image; and a processor having an input to receive input image data for display and an output to provide hologram data for the SLM, wherein the processor is configured to: input image data and convert this to target image data; generate from the target image data hologram data for display as a hologram on the SLM to reproduce a target image; and wherein the target image is distorted to compensate for the projection of the hologram at an acute angle to form the image.

Abstract: This invention relates to holographic image display systems, and to related methods and processor control code. We describe a method of displaying an image holographically, the method including: inputting display image data defining said image for display; processing said image data to determine first image data representing a first spatial frequency portion of said image data and second image data representing a second spatial frequency portion of said image data, wherein said second spatial frequency is higher than said first spatial frequency; displaying a hologram of said first image data on a spatial light modulator (SLM) to form a holographically-generated intermediate real image; modulating said intermediate real image using said second image data to display said image.

Abstract: This invention relates to methods, apparatus, and computer program code for the holographic display of images. We describe a method of displaying an image holographically. The method includes displaying a hologram on pixels of a spatial light modulator (SLM) and illuminating the SLM such that the image is displayed in pixels of a replay field (RPF) of the hologram. The method further includes subdividing the replay field into a plurality of spatially interlaced regions, and displaying holograms for each of the interlaced regions of the replay field sequentially at different times such that in an observer's eye the interlaced regions integrate to give the impression of the image and such that interference between adjacent pixels of the replay field is reduced.

Abstract: The invention relates to techniques for speckle reduction in holographic optical systems, in particular holographic image display systems. We describe a holographic image display system for displaying an image holographically on a display surface, the system including: a spatial light modulator (SLM) to display a hologram; a light source to illuminate said displayed hologram; projection optics to project light from said illuminated displayed hologram onto said display surface to form a holographically generated two-dimensional image, said projection optics being configured to form, at an intermediate image surface, an intermediate two-dimensional image corresponding to said holographically generated image; a diffuser located at said intermediate image surface; and an actuator mechanically coupled to said diffuser to, in operation, move said diffuser to randomise phases over pixels of said intermediate image to reduce speckle in an image displayed by the system.