Light Blue Optics | Date: 2014-12-19
We describe a touch sensing system projecting light defining a touch sheet above a surface and a camera to capture a touch image of light scattered by a pen intersecting the touch sheet. A signal processor identifies a lateral location of the pen. The pen includes a light source to provide a light signal, and the system also includes two photodiodes to detect the signal from the pen. The touch detection is augmented by modelling the signals received at the photodiodes, dependent on the distance and angle of a pen, and using this to derive a probability of the observed received signals given the pen location determined from the touch sheet. This information can be used, for example, to allocate identities to the pens.
Light Blue Optics | Date: 2013-03-25
A touch sensing system, for sensing the position of at least one object with respect to surface, the system comprising: a first, 2D touch sensing subsystem to detect a first location of said object with respect to a surface and to provide first location data; a second, object position sensing subsystem to detect a second location of said object, wherein said second location of said object is not constrained by said surface, and to provide second location data; a system to associate said first location data and said second location and to determine additional object-related data from said association; and a system to report position data for said object, wherein said position data comprises data dependent on at least one of said first and second locations and on said additional object-related data.
Light Blue Optics | Date: 2012-06-15
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 object positions for said plurality of objects; and update said previously identified output object positions using said linked candidate object touch positions.
Light Blue Optics | Date: 2011-12-05
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.
Light Blue Optics | Date: 2013-01-17
We describe a touch sensitive image display device. The device comprises: an image projector to project a displayed image onto a surface in front of the device; a touch sensor light source to project light defining a touch sheet above the displayed image; a camera directed to capture a touch sense image comprising light scattered from the touch sheet by an object approaching the displayed image; and a signal processor to process a the touch sense image to identify a location of the object relative to the displayed image. The camera is able to capture an image projected by the image projector, the image projector is configured to project a calibration image, and the device includes a calibration module configured to use a calibration image from the projector, captured by the camera, to calibrate locations in said captured touch sense image with reference to said displayed image.