| Patent application number | Description | Published |
|---|
| 20090219256 | Systems and Methods for Resolving Multitouch Scenarios for Optical Touchscreens - An optical touch detection system may rely on triangulating points in a touch area based on the direction of shadows cast by an object interrupting light in the touch area. When two interruptions occur simultaneously, ghost points and true touch points triangulated from the shadows can be distinguished from one another without resort to additional light detectors. In some embodiments, a distance from a touch point to a single light detector can be determined or estimated based on a change in the length of a shadow detected by a light detector when multiple light sources are used. Based on the distance, the true touch points can be identified by comparing the distance as determined from shadow extension to a distance calculated from the triangulated location of the touch points. | 09-03-2009 |
| 20100045629 | Systems For Resolving Touch Points for Optical Touchscreens - An optical touch detection system may rely on triangulating points in a touch area based on the direction of shadows cast by an object interrupting light in the touch area. When two interruptions occur simultaneously, ghost points and true touch points triangulated from the shadows can be distinguished from one another without resort to additional light detectors. In some embodiments, a distance from a touch point to a single light detector can be determined or estimated based on a change in the length of a shadow detected by a light detector when multiple light sources are used. Based on the distance, the true touch points can be identified by comparing the distance as determined from shadow extension to a distance calculated from the triangulated location of the touch points. | 02-25-2010 |
| 20100085330 | TOUCH SCREEN SIGNAL PROCESSING - A coordinate detection system can comprise a display screen, a touch surface corresponding the top of the display screen or a material positioned above the screen and defining a touch area, at least one camera outside the touch area and configured to capture an image of space above the touch surface, an illumination system comprising a light source, the illumination system configured to project light from the light source through the touch surface, and a processor executing program code to identify whether an object interferes with the light from the light source projected through the touch surface based on the image captured by the at least one camera. Light can be directed upward by sources positioned behind the screen, by sources positioned behind the screen that direct light into a backlight assembly that directs the light upward, and/or by a forward optical assembly in front of the screen that directs the light upward. | 04-08-2010 |
| 20100090985 | TOUCH SCREEN SIGNAL PROCESSING - A touch screen which uses light sources at one or more edges of the screen which directs light across the surface of the screen and at least two cameras having electronic outputs located at the periphery of the screen to receive light from said light sources. A processor receives the outputs of said cameras and employs triangulation techniques to determine the location of an object proximate to said screen. Detecting the presence of an object includes detecting at the cameras the presence or absence of direct light due to the object, using a screen surface as a mirror and detecting at the cameras the presence or absence of reflected light due to an object. The light sources may be modulated to provide a frequency band in the output of the cameras. | 04-15-2010 |
| 20100097353 | TOUCH SCREEN SIGNAL PROCESSING - A touch screen which uses light sources at one or more edges of the screen which directs light across the surface of the screen and at least two cameras having electronic outputs located at the periphery of the screen to receive light from said light sources. A processor receives the outputs of said cameras and employs triangulation techniques to determine the location of an object proximate to said screen. Detecting the presence of an object includes detecting at the cameras the presence or absence of direct light due to the object, using a screen surface as a mirror and detecting at the cameras the presence or absence of reflected light due to an object. The light sources may be modulated to provide a frequency band in the output of the cameras. | 04-22-2010 |
| 20100103143 | TOUCH SCREEN SIGNAL PROCESSING - A touch screen which uses light sources at one or more edges of the screen which directs light across the surface of the screen and at least two cameras having electronic outputs located at the periphery of the screen to receive light from said light sources. A processor receives the outputs of said cameras and employs triangulation techniques to determine the location of an object proximate to said screen. Detecting the presence of an object includes detecting at the cameras the presence or absence of direct light due to the object, using a screen surface as a mirror and detecting at the cameras the presence or absence of reflected light due to an object. The light sources may be modulated to provide a frequency band in the output of the cameras. | 04-29-2010 |
| 20100207911 | Touch screen Signal Processing With Single-Point Calibration - A coordinate detection system can comprise a display screen, a touch surface corresponding the top of the display screen or a material positioned above the screen and defining a touch area, at least one camera outside the touch area and configured to capture an image of space above the touch surface, and a processor executing program code to identify whether an object interferes with the light from the light source projected through the touch surface based on the image captured by the at least one camera. The processor can be configured to carry out a calibration routine utilizing a single touch point in order to determine a plane corresponding to the touch surface by using mirror images of the features adjacent the touch surface, images of the features, and/or based on the touch point and a normal to the reflective plane defined by an image of the object and its mirror image. | 08-19-2010 |
| 20100225588 | Methods And Systems For Optical Detection Of Gestures - A position detection system can comprise a display device, an input device, and an optical assembly positioned adjacent to the display device. The optical assembly can comprise an image sensor configured to detect light in a space between the display device and the input device. One or both of the imaging assembly and the input device can be configured to direct energy into the space between the display device and the input device, with directing energy comprising reflecting energy and/or emitting energy. A processing device can be configured to use the imaging sensor to determine when an object is in the space and/or to determine motion of the object. | 09-09-2010 |
| 20100229090 | Systems and Methods for Interacting With Touch Displays Using Single-Touch and Multi-Touch Gestures - Embodiments include position detection systems that can identify two touch locations mapped to positions proximate a GUI object, such as a boundary. In response to movement of one or both of the two touch locations, the GUI object can be affected, such as moving the boundary to resize a corresponding object and/or to relocate the boundary, or the GUI object can be selected without movement of the touch locations. Embodiments include single touch gestures, such as identifying a rolling, bending, or other movement occurring while a touch location remains substantially the same and interpreting the movement as an input command. Embodiments may utilize one or more optical sensors having sufficient sensitivity to recognize changes in detected light due to variations in object orientation, makeup or posture caused by the rolling, bending, and/or other movement(s). | 09-09-2010 |
| 20110050649 | Determining the Location of Touch Points in a Position Detection System - A position detection system includes at least two optical units configured to image a space, a memory, and a processing device interfaced to the memory and the optical units. The processing device is configured to access image data from the first and second optical units and use this data to determine at least one of a current first position and a current second position representing touch points on a display. The processing device can define a polygon having at least four sides based the current first and current second positions and can access the memory to store and retrieve the polygon. If the processing device can determine only one of the current first position or the current second position based on the accessed image data, the processing device can use the previously defined polygon to estimate the other position that was not determined using the accessed image data. | 03-03-2011 |
