Abstract: An image capture method comprises generating a synchronization signal based on modulated illumination; and synchronizing image frame capture of at least one image sensor using the synchronization signal with the illumination timing of an active pointer within a region of interest in the field of view of the at least one image sensor.

Abstract: A method for adjusting the position of a light curtain emitted by an illumination assembly over a surface, comprises determining a position of the light curtain; calculating a difference between the determined position of the light curtain and a desired position of the light curtain; and adjusting the position of the illumination assembly based on the calculated difference.

Abstract: A method comprising obtaining a first location of a first pointer contact on an input surface; calculating a restricted area proximate the first location; processing the first pointer contact; and inhibit processing of a second location of a second pointer contact within the restricted area.

Abstract: A method for resolving ambiguities between at least two pointers in a plurality of input regions defining an input area of an interactive input system. The method includes capturing images of the plurality of input regions, the images captured by a plurality of imaging devices having a field of view of at least a portion of the input area, processing image data from the images to identify a plurality of targets for the at least two pointers within the input area, and analyzing the plurality of targets to resolve a real location associated with each pointer.

Abstract: An illumination assembly for an interactive input system (20), comprises at least one imaging device (60) capturing image frames of a region of interest; a plurality of illumination sources (84a, 84b, 84c) associated sociated with the imaging device and being located at different positions relative to the imaging device, the illumination sources providing illumination to the region of interest; and a controller (72) communicating with the illumination sources, the controller conditioning the illumination sources so that the illumination sources provide illumination to the region of interest in succession, the timing of image frame capture by the imaging device being coordinated with the illumination pattern of the illumination sources.

Abstract: A method for generally continuously calibrating an interactive input system, the interactive input system comprising at least two imaging devices having fields of view encompassing a region of interest, at least one of the imaging devices calibrated using a projection matrix having an associated quality metric, the method comprises estimating new values for parameters of the projection matrix based on a plurality of computed locations of at least one pointer brought into proximity with the region of interest; calculating a new quality metric using the new parameter values; and if the new quality metric is more accurate than the existing quality metric, updating the projection matrix using the new parameter values.

Abstract: An interactive input system comprising: a pair of transparent panels separated in a parallel-spaced relationship defining a passage therebetween; a radiation structure directing radiation towards the pair of transparent panels, a first portion of the radiation redirected towards the passage in response to at least one pointer brought into proximity with a surface of one of the transparent panels, and a second portion of the first portion of radiation reflected by the other of the transparent panels back towards the passage; at least two imaging devices positioned adjacent to the pair of transparent panels, each of the at least two imaging devices having a field of view looking into the passage and capturing image frames thereof, the at least two imaging devices capturing the image frames from different vantages; and processing structure for processing the image frames to determine a location of the at least one pointer.

Abstract: An interactive input system comprises a touch surface, and imaging system associated with the touch surface and processing structure. The imaging system comprises an optical sensor array that spans at least a portion of the area of the touch surface, and the processing structure communicates with the imaging system and analyzes images received by the imaging system to determine whether at least one pointer is near to the touch surface and the location of the at least one pointer in respect of the touch surface based at least in part on the edge sharpness of the at least one pointer.

Abstract: An interactive input system comprises an optical waveguide, a radiation source directing radiation into the optical waveguide, the radiation undergoing total internal reflection within the optical waveguide in response to at least one touch input on a surface of the optical waveguide. At least one imaging device is positioned adjacent to the waveguide, the at least one imaging device having a field of view looking inside the optical waveguide and capturing image frames thereof. Processing structure processes the image frames captured by the at least one imaging device to determine a location of the at least one touch input based on a frequency of reflections of the radiation appearing in the image frame.

Abstract: A gesture recognition method comprises capturing images, processing the images to identify at least two clusters of touch points associated with at least two pointers, recognizing a gesture based on motion of the clusters, and updating a display in accordance with the recognized gesture.

Abstract: An illumination structure for an interactive input system having a display surface and a light source for backlighting the display surface is provided. The illumination structure includes at least one redirection structure positioned with respect to the display surface to receive excess light produced by the light source and to redirect the excess light generally across the display surface for backlighting one or more pointers. A method is provided for determining the location of at least one pointer in an interactive input system.

Abstract: A pen tool for use with a machine vision interactive input system comprises an elongate body and a tip arrangement at one end of the body, an end surface of the body at least partially about the tip arrangement carrying light reflective material that is visible to at least one imaging assembly of the interactive input system when the pen tool is angled.

Abstract: An interactive input system comprises at least one imaging assembly having a field of view looking into a region of interest and capturing image frames and processing structure in communication with the at least one imaging assembly. When a pointer exists in captured image frames, the processing structure demodulates the captured image frames to determine frequency components thereof and examines the frequency components to determine at least one attribute of the pointer.

Abstract: An interactive input system comprises at least two imaging assemblies capturing image frames of a region of interest from different vantages and processing structure processing image frames captured by the imaging assemblies to determine the location of a pointer within the region of interest, wherein each imaging assembly comprises an image sensor and integrated signal processing circuitry.

Abstract: An interactive input system comprises a touch surface, and imaging system associated with the touch surface and processing structure. The imaging system comprises an optical sensor array that spans at least a portion of the area of the touch surface, and the processing structure communicates with the imaging system and analyzes images received by the imaging system to determine whether at least one pointer is near to the touch surface and the location of the at least one pointer in respect of the touch surface based at least in part on the edge sharpness of the at least one pointer.

Abstract: An interactive input system comprises at least one imaging device having a field of view looking into a region of interest, a bezel at least partially surrounding the region of interest and having a surface in the field of view of the at least one imaging device, a first radiation source emitting radiation into the region of interact that is generally matched to the characteristics of the bezel so that the radiation emitted by the first radiation source is reflected by the bezel surface generally towards the at least one imaging device and a second radiation source emitting radiation into the region of interest that is generally unmatched to the characteristics of the bezel so that the radiation emitted by the second radiation source is not reflected by the bezel surface.

Abstract: An input panel for an interactive input system comprises an optical waveguide; a first radiation source directing radiation into said optical waveguide, said radiation undergoing total internal reflection within said optical waveguide; a diffusion layer adjacent to and on one side of the optical waveguide, totally internally reflected light being frustrated and escaping the optical waveguide in response to pointer contacts on the diffusion layer; a second radiation source directing radiation towards another side of the optical waveguide that is opposite the one side; and at least one imaging device having a field of view looking at the optical waveguide and capturing image frames, wherein said first and second radiation sources are turned on and off in succession and wherein said first radiation source is turned off when said second radiation source is on and wherein said first radiation source is turned on when said second radiation source is off.

Abstract: A method for resolving ambiguities between at least two pointers in a plurality of input regions defining an input area of an interactive input system. The method includes capturing images of the plurality of input regions, the images captured by a plurality of imaging devices having a field of view of at least a portion of the input area, processing image data from the images to identify a plurality of targets for the at least two pointers within the input area, and analyzing the plurality of targets to resolve a real location associated with each pointer.

Abstract: A method for distinguishing between a plurality of pointers in an interactive input system comprises calculating a plurality of potential coordinates for a plurality of pointers in proximity of an input surface of the interactive input system, displaying visual indicators associated with each potential coordinate on the input surface, and determining real pointer locations and imaginary pointer locations associated with each potential coordinate from the visual indicators.

Abstract: A method of calibrating an interactive input system comprises receiving images of a calibration video presented on a touch panel of the interactive input system. A calibration image is created based on the received images, and features are located in the calibration image. A transformation between the touch panel and the received images is determined based on the located features and corresponding features in the calibration video.