# US 2021/0240324 A1 · Using electrical resistance to estimate force on an electrode during temperature changes > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0240324 A1 - Document ID: US20210240324A1 - Status: Published application - Kind: A1 - Application number: 17/235,190 - Filed: 2021-04-20 - Published: 2021-08-05 - Earliest claimed: 2018-05-04 - Assignees: Synaptics Incorporated - Applicants: Synaptics Incorporated - Inventors: Tom Vandermeijden - Web page: https://patentgrep.com/patent/US20210240324A1 ## CPC - G06F 3/04146: {using pressure sensitive conductive elements delivering a boolean signal and located between crossing sensing lines, e.g. located between X and Y sensing line layers} - G01R 27/14: Measuring resistance by measuring current or voltage obtained from a reference source (G01R27/16, G01R27/20, G01R27/22 take precedence) - G06F 3/0412: {Digitisers structurally integrated in a display} - G06F 3/0414: {using force sensing means to determine a position} - G06F 3/04144: {using an array of force sensing means (position sensing using the local deformation of sensor cells G06F3/0447)} - G06F 3/0416: {Control or interface arrangements specially adapted for digitisers} - G06F 3/0443: {using a single layer of sensing electrodes} - G06F 3/0446: {using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes} - G06F 3/045: using resistive elements, e.g. a single continuous surface or two parallel surfaces put in contact - G06F 3/047: using sets of wires, e.g. crossed wires - G01R 27/02: Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant (by measuring phase angle only G01R25/00) - G06F 2203/04105: Pressure sensors for measuring the pressure or force exerted on the touch surface without providing the touch position - G06F 2203/04106: Multi-sensing digitiser, i.e. digitiser using at least two different sensing technologies simultaneously or alternatively, e.g. for detecting pen and finger, for saving power or for improving position detection - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) ## Abstract A processing system includes sensor circuitry and processing circuitry. The sensor circuitry is configured to, using the sensor electrodes, obtain capacitive measurements of a sensing region, and obtain a resistance measurement of the sensing region. The processing circuitry is coupled to the sensor circuitry. The processing circuitry is configured to determine a location of an input object using the capacitive measurements of the sensing region; and determine a force value based on the resistance measurement and the location of the input object. Determining the force value mitigates a temperature variation of the sensing region affecting the resistance measurement. The processing circuitry is further configured to report the force value. ## Claims ### Claim 1 A processing system, comprising: sensor circuitry configured to, using a plurality of sensor electrodes: obtain a plurality of capacitive measurements of a sensing region; and obtain a resistance measurement of the sensing region; processing circuitry coupled to the sensor circuitry, wherein the processing circuitry is configured to: determine a location of an input object using the plurality of capacitive measurements of the sensing region; determine a force value based on the resistance measurement and the location of the input object, wherein determining the force value mitigates a temperature variation of the sensing region affecting the resistance measurement; and report the force value. ### Claim 2 (depends on 1) The processing system of claim 1, wherein the processing circuitry is further configured to: acquiring the resistance measurement using a subset of the plurality of sensor electrodes in a region that excludes the location of the input object. ### Claim 3 (depends on 2) The processing system of claim 2, wherein the location is a first virtual button, and wherein the processing circuitry is further configured to: exclude a first electrode pair that crosses the first virtual button and including, in the region, a second electrode pair that crosses a second virtual electrode button. ### Claim 4 (depends on 2) The processing system of claim 2, wherein the touch location is a virtual button, and wherein excluding the touch location comprises: acquiring the resistance measurement using an electrode pair comprising a first sensor electrode and a second sensor electrode, the first sensor electrode and the second sensor electrode being on either side of the virtual button. ### Claim 5 (depends on 2) The processing system of claim 2, wherein the touch location is a virtual button of a plurality of virtual buttons, and wherein excluding the touch location comprises: acquiring the resistance measurement using an electrode pair that ends before the plurality of virtual buttons. ### Claim 6 (depends on 1) The processing system of claim 1, wherein the electrical resistance is measured using a sensor electrode in a bifurcated diamond pattern forming a loop comprising a first terminal and a second terminal, the first terminal and the second terminal located at a same edge of the sensing region. ### Claim 7 (depends on 6) The processing system of claim 6, wherein the loop does not overlap a plurality of virtual buttons. ### Claim 8 (depends on 1) The processing system of claim 1, wherein the electrical resistance is measured using a sensor electrode in a divided diamond pattern forming a loop comprising a first terminal and a second terminal, the first terminal and the second terminal located at a same edge of the sensing region, wherein the divided diamond pattern comprises, for at least one diamond, a trace separated from a remaining portion of the diamond. ### Claim 9 (depends on 1) The processing system of claim 1, wherein the processing circuitry is further configured to: estimate a rate of change of a temperature from a plurality of resistance measurements acquired over a time interval; determine, based on the rate of change of the temperature, an estimated temperature responsive to determining the location of the input object being on the sensing region; and determine the force using the estimated temperature and the resistance measurement. ### Claim 10 (depends on 1) The processing system of claim 1, wherein the processing circuitry is further configured to: acquire a plurality of resistance measurements over a time interval; determine a derivative of the plurality of resistance measurements; and determine the force according to a spike in the derivative. ### Claim 11 An input device, comprising: a plurality of sensor electrodes; and a processing system coupled to the plurality of sensor electrodes, wherein the processing system is configured to: obtain a plurality of capacitive measurements of a sensing region; determine a location of an input object using the plurality of capacitive measurements of the sensing region; obtain a resistance measurement of the sensing region; determine a force value based on the resistance measurement and the location of the input object, wherein determining the force value mitigates a temperature variation of the sensing region affecting the resistance measurement; and report the force value. ### Claim 12 (depends on 11) The input device of claim 11, wherein the plurality of sensor electrodes comprises at least one sensor electrode for acquiring the resistance measurement, wherein the at least one sensor electros is nonoverlapping with the location of the input object. ### Claim 13 (depends on 12) The input device of claim 12, wherein the at least one sensor electrode comprises a first electrode pair and a second electrode pair, the first electrode pair overlapping a first virtual button and the second electrode pair overlapping a second virtual button, wherein the location is the first virtual button, and wherein the processing system is further configured to: acquire the resistance measurement using the second electrode pair based on the location being the first virtual button. ### Claim 14 (depends on 12) The input device of claim 12, wherein the at least one sensor electrode comprises an electrode pair comprising a first sensor electrode and a second sensor electrode, the first sensor electrode and the second sensor electrode being on either side of a virtual button, wherein the location is the virtual button. ### Claim 15 (depends on 12) The input device of claim 12, wherein the at least one sensor electrode comprises an electrode pair that ends before a virtual button, wherein the location is the virtual button. ### Claim 16 (depends on 11) The input device of claim 11, wherein plurality of sensor electrodes comprises a sensor electrode in a bifurcated diamond pattern forming a loop comprising a first terminal and a second terminal, the first terminal and the second terminal located at a same edge of the sensing region. ### Claim 17 (depends on 16) The input device of claim 16, wherein the loop does not overlap a plurality of virtual buttons. ### Claim 18 (depends on 11) The input device of claim 11, wherein the plurality of sensor electrodes comprises a sensor electrode in a divided diamond pattern forming a loop comprising a first terminal and a second terminal, the first terminal and the second terminal located at a same edge of the sensing region, wherein the divided diamond pattern comprises, for at least one diamond, a trace separated from a remaining portion of the diamond. ### Claim 19 A method comprising: obtaining a plurality of capacitive measurements of a sensing region; determining a location of an input object using the plurality of capacitive measurements of the sensing region; obtaining a resistance measurement of the sensing region; determining a force value based on the resistance measurement and the location of the input object, wherein determining the force value mitigates a temperature variation of the sensing region affecting the resistance measurement; and reporting the force value. ### Claim 20 (depends on 19) The method of claim 19, further comprising: estimating a rate of change of a temperature from a plurality of resistance measurements acquired over a time interval; determining, based on the rate of change of the temperature, an estimated temperature responsive to determining the location of the input object being on the sensing region; and determining the force using the estimated temperature and the resistance measurement.