Abstract: Methods and apparatus for correcting electrical noise coupling from a liquid crystal module to a plurality of sense elements disposed within a touch sensor panel, and for reducing errors in touch detection algorithms. Erroneous signal values detected by the sense elements may be corrected by utilizing a set of reference elements for detecting noise common to both the sense elements and the reference elements, and a correction module for effectively subtracting out the noise from the sensed values. Errors in touch detection algorithms may be reduced by providing a more uniform spacing between successive sense elements. In some embodiments, one or more dummy ground elements may be inserted between adjacent sense elements in order to reduce signal interference.

Abstract: Integrated touch sensor and solar panel configurations that may be used on portable devices, particularly handheld portable devices such as a media player or phone are disclosed. The integrated touch sensor array and solar cell stack-ups may include electrodes that are used both for collecting solar energy and for sensing on a touch sensor array. By integrating both the touch sensors and the solar cell layers into the same stack-up, surface area on the portable device may be conserved. In addition to being used for capacitive sensing, the integrated touch sensor and solar panel configurations may also be used for optical sensing.

Abstract: A method for transferring single layer thin film from a temporary substrate to a target substrate is disclosed. A base layer may be fabricated onto a fabrication sheet. A single layer thin film of conductive material may be patterned onto the base layer. A temporary transfer substrate may be adhered to the single layer thin film. The fabrication sheet may be removed and the base layer-patterned single layer thin film-temporary transfer substrate block transferred to a target substrate, where the base layer may contact the target substrate. Upon completion of the transfer, the temporary transfer substrate may be removed.

Abstract: Determination of phases of multiple stimulation signals to be simultaneously applied to a touch sensor panel is disclosed. A matrix may be determined that is invertible and has a gain greater than one, where each row of the matrix may represent a single step among multiple steps needed to compute values for generating an image of touch, each column of the matrix may represent a drive line of the touch sensor panel to be stimulated, and each element of the matrix may represent the phase of the stimulation signal to be applied to a particular drive line in a particular step. For each step, stimulation signals having phases in accordance with the matrix elements may be simultaneously applied to the drive lines of the touch sensor panel.

Abstract: Embodiments of the invention include an IC that includes a core used for ordinary operation and a thin power circuit. The thin power circuit can be configured to use very little power. The IC can also include a digital interface and a connection thereto. The IC can initiate transition to low power mode during which the core and various I/O pads can be shut down. However, the thin power circuit can be kept powered up. The thin power circuit can monitor the digital interface for a predefined wake up signal. When the wake up signal is detected, the thin power circuit can power up the core and any powered down I/O pads. The thin power circuit can also include a dedicated power on reset (POR) cell. This POR cell can be distinct than other POR cells used for the IC and can be specifically designed to for efficient operation.

Abstract: A multi-stimulus controller for a multi-touch sensor is formed on a single integrated circuit (single-chip). The multi-stimulus controller includes a transmit oscillator, a transmit signal section that generates a plurality of drive signals based on a frequency of the transmit oscillator, a plurality of transmit channels that transmit the drive signals simultaneously to drive the multi-touch sensor, a receive channel that receives a sense signal resulting from the driving of the multi-touch sensor, a receive oscillator, and a demodulation section that demodulates the received sense signal based on a frequency of the receive oscillator to obtain sensing results, the demodulation section including a demodulator and a vector operator.

Abstract: A system is disclosed for enhancing the stimulation signal bandwidth for a touch sensor panel and maintaining relatively uniform touch sensitivity over the touch sensor panel surface. In one embodiment, a bandwidth enhancement circuit is coupled in parallel to a sensor circuit. The sensor circuit includes a source of stimulating voltage, a drive line, a sense line, and a charge amplifier. The drive line and the sense line are coupled with each other by a mutual capacitance Csig. The bandwidth enhancement circuit can be a RC circuit coupled in parallel to the sensor circuit. The bandwidth enhancement circuit can be represented by two serially coupled resistors, each of which is also coupled to ground on one end, and two capacitors. In particular, one of the capacitors couples the bandwidth enhancement circuit to the drive line, and the other capacitor couples the bandwidth enhancement circuit to the sense line.

Abstract: Devices having one or more sensors located outside a viewing area of a touch screen display are disclosed. The one or more sensors can be located behind an opaque mask area of the device; the opaque mask area extending between the sides of a housing of the device and viewing area of the touch screen display. In addition, the sensors located behind the mask can be separate from a touch sensor panel used to detect objects on or near the touch screen display, and can be used to enhance or provide additional functionality to the device. For example, a device having a sensor located outside the viewing area can be used to detect objects in proximity to a functional component incorporated in the device, such as an ear piece (i.e., speaker for outputting sound). The sensor can also output a signal indicating a level of detection which may be interpreted by a controller of the device as a level of proximity of an object to the functional component.

Abstract: Methods and apparatus for normalizing the effects of the changes to the parasitic capacitive coupling that can occur in touch sensor panels so as to reduce or eliminate the appearance of erroneous touch events. In some embodiments, at some time prior to regular device use (e.g. during factory calibration), a conductive sheet is initially positioned so as to entirely cover a touch surface of a touch sensor panel. A set of sensed signals may be determined upon driving the drive lines and sensing the sense lines of the panel. Correctional coefficients may then be calculated based in part upon the difference between a sensed signal and an expected signal. The correctional coefficients may then be stored in the device and used to determine signal corrections for a set of measured signals during normal operation.

Abstract: A touch screen including display pixels with capacitive elements is provided. The touch screen includes first common voltage lines connecting capacitive elements in adjacent display pixels, and a second common voltage line connecting first common voltage lines. The pixels can be formed as electrically separated regions by including breaks in the common voltage lines. The regions can include a drive region that is stimulated by stimulation signals, a sense region that receives sense signals corresponding to the stimulation signals. A grounded region can also be included, for example, between a sense region and a drive region. A shield layer can be formed of a substantially high resistance material and disposed to shield a sense region. A black mask line and conductive line under the black mask line can be included, for example, to provide low-resistance paths between a region of pixels and touch circuitry outside the touch screen borders.

Abstract: Methods and apparatus for preventing fluctuations in ambient light from affecting the optical input mechanism of a liquid crystal display device. In one embodiment, an independent light source is adapted to generate electromagnetic signals through the cover glass of the display device. When the user's finger is proximate to a certain region of the touch panel, the electromagnetic signals reflect off of the user's finger and back through the cover glass. One or more photosensors monitoring the presence of these reflected signals service the various regions on the touch panel where input may be detected. Thus, when the reflected signals are detected at a certain region, the user's finger may be assumed to be present.

Abstract: Fabrication of thin sheets of glass or other substrate material for use in devices such as touch sensor panels is disclosed. A pair of thick glass sheets, typically with thicknesses of 0.5 mm or greater each, may each be patterned with thin film on a surface, sealed together to form a sandwich with the patterned surfaces facing each other and spaced apart by removable spacers, either or both thinned on their outside surfaces to thicknesses of less than 0.5 mm each, and separated into two thin glass sheets. A single thick glass sheet, typically with a thickness of 0.5 mm or greater, may be patterned, covered with a protective layer over the pattern, thinned on its outside surface to a thickness of less than 0.5 mm, and the protective layer removed. This thinness of less than 0.5 mm may be accomplished using standard LCD equipment, despite the equipment having a sheet minimum thickness requirement of 0.5 mm.

Abstract: A touch sensor panel is disclosed having an array of co-planar single-layer touch sensors fabricated on a single side of a substrate. The sense (or drive) lines can be fabricated in a single strip as columnar or zig-zag patterns in a first orientation, and the drive (or sense) lines can be fabricated as rows of polygonal (e.g. brick-shaped or pentagonal) conductive areas in a second orientation. Each sense (or drive) line in the first orientation can be coupled to a separate metal trace in the border area of the touch sensor panel, and each polygonal area in the second orientation can also be coupled to a metal trace in the border area of the touch sensor panel. The metal traces can allow both the row and column lines to be routed to the same edge of the substrate for flex circuit attachment.

Abstract: A method of laminating a surface of a flexible material to a surface of a rigid, curved material. The method includes pressing an area of the surface of the flexible material into the surface of the rigid, curved material with a holder to create a contact area while the flexible material is conformed to the holder, which has a curvature greater than a curvature of the rigid, curved material surface; and changing the contact area between the surface of the flexible material and the surface of the rigid, curved material while maintaining pressure on the contact area until the surface of the flexible material and the surface of the rigid curved material are laminated.

Abstract: Capacitive multi-touch sensor panels in which both row and column traces may be formed on a single conducting surface are disclosed. These stack-ups may be made thinner and more flexible allowing them to be particularly well-suited for curved or other non-flat touch sensor panels, such as those that might be present on a mouse or other device designed to be grasped by a user's hand. Curved sensor panel arrays that may be formed from flat substrates are also disclosed. These sensor panel configurations may include channels around the periphery of the array. These channels allow the flat array to lie flat when applied to a curved surface, such as the inside of the curved surface. The pattern of the touch sensor elements may be adjusted across the array to avoid the channels.

Abstract: A touch sensor panel is disclosed including the use of ground guards or ground isolation bars to improve the touch event detection capabilities of the touch sensor panel. Ground isolation bars can be formed between connecting traces and adjacent sense lines to shunt near-field lines to ground and reduce unwanted capacitive coupling between the connecting traces and the sense lines. Ground guards can be formed between the drive and sense lines to partially or fully surround a sense line and shunt near-field lines to ground and improve the touch event detection capabilities of the sensor.

Abstract: The formation of improved reliability conductive traces in touch sensor panels that are less prone to failures due to environmental effects is disclosed. Conductive traces, which can be formed from a stackup of metal layers or a single metal layer, can be protected with an additional photoimageable passivation layer of a material such as an organic polymer. This photoimageable coating can be patterned so that it does not appear in the visible area of the touch sensor panel, with much finer tolerances than conventional passivation layers to help keep product dimensions to a minimum.

Abstract: An apparatus for generating an image of touch on or about a touch-sensitive surface comprising a touch panel is disclosed. The touch panel can include a plurality of touch sensors configured for detecting one or more touch events occurring at distinct locations at about the same time. Each touch event can comprise a touching of an object against the touch-sensitive surface. A plurality of receive channels can be coupled to the touch panel for generating values representative of detected touch events. The receive channels can include a charge redistribution successive approximation register digital-to-analog converter (SAR ADC) configured to convert an analog waveform into a digital representation via a binary search and outputting the digital representation to an output register. The SAR ADC architecture can be such that it the dynamic input range can be scaled and offset adjusted.

Abstract: The use of multiple stimulation frequencies and phases is disclosed to detect touch events on a touch sensor panel in a low-power state. Simultaneously during every frame, a number of rows of the touch sensor panel can be driven with a positive phase of one or more stimulation signals, and the same number of different rows can be driven with the anti-phase of those same stimulation signals. Because the same number of rows are stimulated with the in-phase and anti-phase components of the one or more stimulation signals, the resulting charges injected into a given column cancel each other out. However, a touch event will create an imbalance, and a non-zero charge will be detected. The detection of the touch event can then trigger the system to wake up, activate a panel processor, and perform a full panel scan, where the location of the touch event can be identified.

Abstract: The efficient incorporation of RFID circuitry within touch sensor panel circuitry is disclosed. The RFID antenna can be placed in the touch sensor panel, such that the touch sensor panel can now additionally function as an RFID transponder. No separate space-consuming RFID antenna is necessary. Loops (single or multiple) forming the loop antenna of the RFID circuit (for either reader or tag applications) can be formed from metal on the same layer as metal traces formed in the borders of a substrate. Forming loops from metal on the same layer as the metal traces are advantageous in that the loops can be formed during the same processing step as the metal traces, without requiring a separate metal layer.