Abstract: Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for input classification for multi-touch systems. In one aspect, a method includes receiving data describing a first region of contact with a touch sensitive display and a second region of contact with the touch sensitive display. The method includes determining at least one characteristic of the first region of contact. The method includes based on the at least one characteristic of the first region of contact, determining that the first region of contact corresponds to intended touch input provided by a user's body part or stylus. The method includes determining at least one characteristic of the second region of contact. The method includes based on the at least one characteristic of the second region of contact, determining that the second region of contact corresponds to incidental touch input provided by a user's resting body part.

Abstract: Objects displayed on a display component of a multi-touch display device may be assigned to and displayed at various visual layers, with each visual layer corresponding to a different depth relative to a foreground (or background) of the display component of the multi-touch display device. One or more annotations may be generated in response to user interaction with the multi-touch display device, with each annotation being assigned to an appropriate visual layer.

Abstract: Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for input classification for multi-touch systems. In one aspect, a method includes receiving data describing a first region of contact with a touch sensitive display, a second region of contact with the touch sensitive display, and a third region of contact with the touch sensitive display, the second region of contact being separate from the first region of contact and the third region of contact being separate from the first region of contact and the second region of contact. The method includes classifying the first region of contact as a touch point provided by a user's body part. The method includes classifying the second region of contact as incidental touch input provided by a user's resting body part. The method includes classifying the third region of contact as a stylus input.

Abstract: One embodiment provides a system for processing gesture inputs on a touch screen display. The system receives a gesture input on the touch screen display. When the gesture is recognized as invoking an annotation canvas, the system determines the height, width and location of an annotation canvas, and displays the annotation canvas on the touch screen display. Then, in response to an input gesture within the annotation canvas, the system recognizes the gesture as an annotation gesture, and executes the annotation gesture. In response to receiving an input gesture outside of the annotation canvas, the gesture is interpreted by the system as a navigation input.

Abstract: Methods and systems for interfacing with multi-input devices employ various techniques for controlling the window framing of images. Such techniques provide control, including moving, sizing, and orientating, of one or more displayed window frames in which one or more images are displayed.

Abstract: Systems are described for transmitting and receiving signals in an active stylus for a capacitive touch sensor, for which the systems have at least one circuit for receiving a current from an electrode and for transmitting a voltage onto the electrode. The systems include components for receiving the current in a receiving mode, a switch, and a switchmode power supply circuit having at least a transformer and a diode, for which the diode is coupled to the transformer. In a transmission mode, there is means for electrically isolating at least some of the components configured for receiving the current in the receiving mode from the voltage formed across the stray capacitance. In the receiving mode, there is a means for electrically isolating at least some of the components configured for receiving the current in the receiving mode from an inductance of the transformer in the switchmode power supply circuit.

Abstract: A touch-screen device includes an imaging waveguide, in which the imaging waveguide has a radiation receiving surface and an imaging surface different than the radiation receiving surface. The imaging waveguide is configured to receive, at the radiation receiving surface, radiation emitted by a contact receiving structure, and transmit the received radiation from a position on the radiation receiving surface to a position and/or angle of incidence on the imaging surface as a function of the position on the radiation receiving surface at which the transmitted radiation was received. An imaging sensor coupled to the imaging surface of the imaging optical waveguide is configured to detect radiation incident upon the imaging surface of the imaging optical waveguide. A processing device coupled to the imaging sensor is configured to determine contact points on the exposed contact surface of a contact receiving structure based on radiation detected by the imaging sensor.

Abstract: Methods, systems, and apparatus relate to touch sensors that are configured to measure input applied to the sensor from a user. Some implementations involve the measurement of changes in capacitance between pairs of adjacent patterned electrodes to detect input at a touch sensor.

Abstract: Methods and systems for interfacing with multi-input devices employ various techniques for controlling the window framing of images. Such techniques provide control, including moving, sizing, and orientating, of one or more displayed window frames in which one or more images are displayed.

Abstract: A tensioning system includes a layer of a device and a flexible overlay film that is configured to cover the layer of the device. A tensioning mechanism is configured to tension the flexible overlay film against the layer of the device throughout a periphery. The tensioning mechanism also is configured to allow movement of the flexible overlay film in two dimensions.

Abstract: Systems are described for transmitting and receiving signals in an active stylus for a capacitive touch sensor, for which the systems have at least one circuit for receiving a current from an electrode and for transmitting a voltage onto the electrode. The systems include components for receiving the current in a receiving mode, a switch, and a switchmode power supply circuit having at least a transformer and a diode, for which the diode is coupled to the transformer. In a transmission mode, there is means for electrically isolating at least some of the components configured for receiving the current in the receiving mode from the voltage formed across the stray capacitance. In the receiving mode, there is a means for electrically isolating at least some of the components configured for receiving the current in the receiving mode from an inductance of the transformer in the switchmode power supply circuit.

Abstract: A matrix of light emitting diodes is positioned behind a liquid crystal layer of a display device. The light emitting diodes operate in both light emitting and light detecting modes. Consequently, the display device is able to sense objects or fingers approaching or in contact with a front display surface of the display device based on changes in incident light on the matrix that are observed by one or more of the light emitting diodes operating in the light detecting mode.

Abstract: Methods, systems, and apparatus relate to capacitive touch sensors with a fine-pointed, active stylus. The active stylus is configured to receive a signal from the capacitive touch sensor for synchronizing a time base of the stylus with the capacitive touch sensor. The active stylus is configured to receive a signal from a matrix of the capacitive touch sensor to measure a first position along one axis, and transmit a signal from the single electrode of the stylus to the matrix to indicate a second position of the stylus along another axis of the matrix. The stylus can transmit the received signal to report the first position of the stylus.

Abstract: A graphical user interface is rendered on a display screen of a touch screen device. The display screen includes a display area for rendering images, and the graphical user interface of the application is rendered in a portion of the display area. Digital touch data is generated in response to user interactions with a touch-sensitive surface of the touch screen device. the digital touch data into OS touch events and application touch events. The OS touch events, application touch events, and application location information are received at a system hook. The application location information identifies the portion of the display area of the touch screen device in which the graphical user interface of the application is rendered. The system hook filters the OS touch events and the application touch events based on the application location information and provides the filtered OS touch events and application touch events to the application.

Abstract: A display device comprises a display panel including a display region configured to display one or more image objects and an overscan region configured to prevent the display of images within the overscan region, a touchscreen panel overlying the display region and the overscan region configured to detect and generate engagement data indicative of detected engagement, and a computer processor configured to access first engagement data, determine that the first engagement data reflects engagement with at least one portion of the touchscreen panel correspondingly overlapping with the overscan region, identify a first particular engagement input type based on the first engagement data, and instruct the display panel to invoke the display of the one or more image objects in the display region or to change the display of the one or more image objects in the display region.

Abstract: Placement by one or more input mechanisms of a touch point on a multi-touch display device that is displaying a three-dimensional object is detected. A two-dimensional location of the touch point on the multi-touch display device is determined, and the touch point is matched with a three-dimensional contact point on a surface of the three-dimensional object that is projected for display onto the image plane of the camera at the two-dimensional location of the touch point. A change in applied pressure at the touch point is detected, and a target depth value for the contact point is determined based on the change in applied pressure. A solver is used to calculate a three-dimensional transformation of the three-dimensional object using an algorithm that reduces a difference between a depth value of the contact point after object transformation and the target depth value.

Abstract: Techniques for disambiguating touch data and determining user assignment of touch points detected by a touch sensor are described. The techniques leverage both user-specific touch data projected onto axes and non-user-specific touch data captured over a complete area.

Abstract: A graphical user interface is rendered on a display screen of a touch screen device. The display screen includes a display area for rendering images, and the graphical user interface of the application is rendered in a portion of the display area. Digital touch data is generated in response to user interactions with a touch-sensitive surface of the touch screen device. A module of an operating system residing on the touch screen device is used to convert the digital touch data into OS touch events. The OS touch events and application location information are received at a system hook. The application location information identifies the portion of the display area of the touch screen device in which the graphical user interface of the application is rendered. The system hook filters the OS touch events based on the application location information and provides the filtered OS touch events to the application.

Abstract: A light injection system includes a radiation source, an optical waveguide, and an optical component. The radiation source emits radiation and is oriented relative to the optical waveguide such that a first portion of radiation emitted from the radiation source couples into the optical waveguide as emitted from the radiation source and a second portion of radiation emitted from the radiation source bypasses the optical waveguide as emitted from the radiation source. The optical component redirects at least some of the second portion of radiation emitted from the radiation source that would otherwise bypass the optical waveguide and enables at least some of the redirected radiation to couple into the optical waveguide instead of bypass the optical waveguide.

Abstract: Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for digital signal processing (DSP) techniques for generally improving a signal-to-noise ratio (SNR) of capacitive touch sensors.