# US 8,786,554 B2 · Priority and combination suppression techniques (PST/CST) for a capacitive keyboard > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,786,554 B2 - Document ID: US8786554B2 - Status: Granted - Kind: B2 - Application number: 11/750,588 - Filed: 2007-05-18 - Published: 2008-01-10 - Granted: 2014-07-22 - Earliest claimed: 2006-07-10 - Assignees: Atmel Corporation - Applicants: Luben Hristov - Inventors: Luben Hristov - Web page: https://patentgrep.com/patent/US8786554B2 ## CPC - G06F 3/0416: {Control or interface arrangements specially adapted for digitisers} - G06F 3/0237: {using prediction or retrieval techniques} - G06F 3/04886: by partitioning the display area of the touch-screen or the surface of the digitising tablet into independently controllable areas, e.g. virtual keyboards or menus - H03K 17/9622: {using a plurality of detectors, e.g. keyboard} - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - H03K: PULSE TECHNIQUE (measuring pulse characteristics G01R; modulating sinusoidal oscillations with pulses H03C; transmission of digital information H04L; discriminator circuits detecting phase difference between two signals by counting or integrating cycles of oscillation H03D3/04; automatic control, starting, synchronisation or stabilisation of generators of electronic oscillations or pulses where the type of generator is irrelevant or unspecified H03L; coding, decoding or code conversion, in general H03M) ## Abstract Apparatus and methods are described for selecting which of a plurality of simultaneously activated keys in a keyboard based on an array of capacitive sensors is a key intended for selection by a user. Combinations of keys which are commonly activated simultaneously when a user intends to select a single key are identified and associated with the single keys most likely to give rise to the identified combinations during normal use of the keyboard. In use, an observed combination of simultaneously activated keys is compared with predefined combinations of keys corresponding to those identified as being commonly activated simultaneously. If the combination of activated keys matches one of the predefined combinations, the most likely intended key associated with the matched one of the predefined combination of keys is taken to be most likely intended key. ## Claims ### Claim 1 An apparatus comprising: a touch-sensitive interface that comprises a plurality of sensing areas within a sensing region; and one or more computer-readable non-transitory storage media coupled to the touch-sensitive interface that embody logic operable when executed to: receive a first set of signals, the first set of signals comprising two or more output signals responsive to two or more substantially contemporaneous capacitive couplings, each of the substantially contemporaneous capacitive couplings occurring between a pointing object and one of the plurality of sensing areas within the sensing region of the touch-sensitive interface; and select, when the sensing areas corresponding to the substantially contemporaneous capacitive couplings do not constitute one of a plurality of predefined combinations of one or more of the sensing areas, each predefined combination having a preselected sensing area of the plurality of sensing areas, one of the sensing areas corresponding to the substantially contemporaneous capacitive couplings based at least in part on scaled output signals of the first set of signals, wherein each of the output signals is scaled by a predetermined scale factor associated with a priority rank of the one of the plurality of sensing areas corresponding to the substantially contemporaneous capacitive coupling to which the output signal corresponds. ### Claim 2 (depends on 1) The apparatus of claim 1, wherein a particular predefined combination of the plurality of predefined combinations comprises sensing areas beyond sensing areas neighboring the preselected sensing area of the particular predefined combination. ### Claim 3 (depends on 1) The apparatus of claim 1, wherein a particular predefined combination of the plurality of predefined combinations comprises four sensing areas. ### Claim 4 (depends on 1) The apparatus of claim 1, wherein a particular predefined combination of the plurality of predefined combinations comprises three sensing areas arranged along a line and the preselected sensing area for the particular predefined combination is a middle one of the three sensing areas along the line. ### Claim 5 (depends on 4) The apparatus of claim 4, wherein the line corresponds with a direction of approach or extent of a pointing object during normal use. ### Claim 6 (depends on 1) The apparatus of claim 1, wherein a particular predefined combination of the plurality of predefined combinations comprises four sensing areas arranged along a line and the preselected sensing area for the particular predefined combination is located at an end of the line. ### Claim 7 (depends on 6) The apparatus of claim 6, wherein the line corresponds with a direction of approach or extent of a pointing object during normal use, and the preselected sensing area for the particular predefined combination is a second most distant one of the four sensing areas along the line relative to the direction of approach or extent of the pointing object during normal use. ### Claim 8 (depends on 1) The apparatus of claim 1, wherein a particular predefined combination of the plurality of predefined combinations comprises a contiguous series of neighboring sensing areas. ### Claim 9 (depends on 1) The apparatus of claim 1, wherein a particular predefined combination of the plurality of predefined combinations comprises at least three sensing areas. ### Claim 10 (depends on 1) The apparatus of claim 1, the logic further operable when executed to: receive a second set of signals, the second set of signals comprising two or more output signals responsive to two or more substantially contemporaneous capacitive couplings, each of the substantially contemporaneous capacitive couplings occurring between a pointing object and one of the plurality of sensing areas within the sensing region of the touch-sensitive interface; and select, when the sensing areas corresponding to the substantially contemporaneous capacitive couplings constitute a particular predefined combination of the plurality of predefined combinations, the preselected sensing area of the particular predefined combination. ### Claim 11 A method comprising: receiving a first set of signals, the first set of signals comprising two or more output signals responsive to two or more substantially contemporaneous capacitive couplings, each of the substantially contemporaneous capacitive couplings occurring between a pointing object and one of a plurality of sensing areas within a sensing region of a touch-sensitive interface; and selecting, when the sensing areas corresponding to the substantially contemporaneous capacitive couplings do not constitute one of a plurality of predefined combinations of one or more of the sensing areas, each predefined combination having a preselected sensing area of the plurality of sensing areas, one of the sensing areas corresponding to the substantially contemporaneous capacitive couplings based at least in part on scaled output signals of the first set of signals, wherein each of the output signals is scaled by a predetermined scale factor associated with a priority rank of the one of the plurality of sensing areas corresponding to the substantially contemporaneous capacitive coupling to which the output signal corresponds. ### Claim 12 (depends on 11) The method of claim 11, wherein a particular predefined combination of the plurality of predefined combinations comprises sensing areas beyond sensing areas neighboring the preselected sensing area of the particular predefined combination. ### Claim 13 (depends on 11) The method of claim 11, wherein a particular predefined combination of the plurality of predefined combinations comprises a contiguous series of neighboring sensing areas. ### Claim 14 (depends on 11) The method of claim 11, wherein a particular predefined combination of the plurality of predefined combinations comprises three sensing areas arranged along a line and the preselected sensing area for the particular predefined combination is a middle one of the three sensing areas along the line. ### Claim 15 (depends on 14) The method of claim 14, wherein the line corresponds with a direction of approach or extent of a pointing object during normal use. ### Claim 16 (depends on 11) The method of claim 11, further comprising: receiving a second set of signals, the second set of signals comprising two or more output signals responsive to two or more substantially contemporaneous capacitive couplings, each of the substantially contemporaneous capacitive couplings occurring between a pointing object and one of a plurality of sensing areas within a sensing region of a touch-sensitive interface; and selecting, when the sensing areas corresponding to the substantially contemporaneous capacitive couplings constitute a particular predefined combination of a plurality of predefined combinations of one or more of the sensing areas, each predefined combination having a preselected sensing area, the preselected sensing area of the particular predefined combination. ### Claim 17 A computer-readable non-transitory storage media embodying logic that is operable when executed to: receive a first set of signals, the first set of signals comprising two or more output signals responsive to two or more substantially contemporaneous capacitive couplings, each of the substantially contemporaneous capacitive couplings occurring between a pointing object and one of a plurality of sensing areas within a sensing region of a touch-sensitive interface; and select, when the sensing areas corresponding to the substantially contemporaneous capacitive couplings do not constitute one of a plurality of predefined combinations of one or more of the sensing areas, each predefined combination having a preselected sensing area, one of the sensing areas corresponding to the substantially contemporaneous capacitive couplings based at least in part on scaled output signals of the first set of signals, wherein each of the output signals is scaled by a predetermined scale factor associated with a priority rank of the one of the plurality of sensing areas corresponding to the substantially contemporaneous capacitive coupling to which the output signal corresponds. ### Claim 18 (depends on 17) The media of claim 17, wherein a particular predefined combination of the plurality of predefined combinations comprises sensing areas beyond sensing areas neighboring the preselected sensing area of the particular predefined combination. ### Claim 19 (depends on 17) The media of claim 17, wherein a particular predefined combination of the plurality of predefined combinations comprises a contiguous series of neighboring sensing areas. ### Claim 20 (depends on 17) The media of claim 17, wherein a particular predefined combination of the plurality of predefined combinations comprises three sensing areas arranged along a line and the preselected sensing area for the particular predefined combination is a middle one of the three sensing areas along the line. ### Claim 21 (depends on 20) The media of claim 20, wherein the line corresponds with a direction of approach or extent of a pointing object during normal use. ### Claim 22 (depends on 17) The media of claim 17, the logic further operable when executed to: receive a second set of signals, the second set of signals comprising two or more output signals responsive to two or more substantially contemporaneous capacitive couplings, each of the substantially contemporaneous capacitive couplings occurring between a pointing object and one of the plurality of sensing areas within the sensing region of the touch-sensitive interface; and select, when the sensing areas corresponding to the substantially contemporaneous capacitive couplings constitute a particular predefined combination of a plurality of predefined combinations of one or more of the sensing areas, each predefined combination having a preselected sensing area, the preselected sensing area of the particular predefined combination.