# US 2022/0034767 A1 · Fluid coverage sensing system and method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2022/0034767 A1 - Document ID: US20220034767A1 - Status: Published application - Kind: A1 - Application number: 17/503,294 - Filed: 2021-10-16 - Published: 2022-02-03 - Earliest claimed: 2015-12-03 - Assignees: Ventana Medical Systems, Inc. - Applicants: Ventana Medical Systems, Inc. - Inventors: Raymond Kozikowski, III; Marian Mikaela Rygelski; Matthew Thurman - Web page: https://patentgrep.com/patent/US20220034767A1 ## CPC - G01N 1/312: {for samples mounted on planar substrates} - G01N 27/02: by investigating impedance - G01V 3/06: using AC - G01N 35/1002: {Reagent dispensers} - G01N 35/1016: {Control of the volume dispensed or introduced} - G01N 2035/1025: {Fluid level sensing} - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) - G01V: GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS (means for indicating the location of accidentally buried, e.g. snow-buried, persons A63B29/02) ## Abstract A system for applying a fluid to a substrate bearing a sample for analysis has an array of sensor plates positioned to sense the presence of fluid in contact with respective areas of the substrate. In a particular embodiment, fluid presence in different areas of the substrate is sensed by the effect of the fluid and its identity on the impedances of capacitors formed between sensor plates within the array. In a more particular embodiment, by polling the sensor array continually while fluid is applied to the substrate determine a coverage map, a fluid dispensing mechanism can be controlled to efficiently cover the entire substrate with fluid a minimal amount of fluid, thereby reducing waste. ## Claims ### Claim 1 A method for identifying a liquid dispensed to a surface, comprising: (a) positioning a sensor array in the vicinity of a substrate, the substrate comprising the surface to which the liquid is dispensed, the sensor comprising an array of capacitor plates; (b) measuring an electrical property of at least one capacitor plate responsive to alternating currents at one or more of a plurality of different frequencies; (c) identifying the liquid dispensed on the surface of the substrate that is present between the at least one pair of capacitor plates based on the measured electrical property at the one or more of the plurality of different frequencies. ### Claim 2 (depends on 1) The method of claim 1, wherein identifying comprises identifying the liquid based on a logistic regression. ### Claim 3 (depends on 1) The method of claim 1, wherein identifying comprises identifying the liquid based on a trained neural network. ### Claim 4 (depends on 1) The method of claim 1, wherein measuring comprises measuring the impedance of the at least one capacitor plate responsive to AC current with a voltage of 1 to 10 volts at each of the plurality of different frequencies. ### Claim 5 (depends on 1) The method of claim 1, wherein the plurality of different frequencies comprises a plurality of different frequencies over a range from one to ten thousand kilohertz. ### Claim 6 (depends on 1) The method of claim 1, wherein the array of coplanar capacitive plates is integrated into the substrate. ### Claim 7 (depends on 1) The method of claim 1, wherein the electric property comprises one of a voltage, a current, a capacitance, and an impedance. ### Claim 8 (depends on 1) The method of claim 1, wherein the array of capacitor plates are arranged in a grid-like array. ### Claim 9 (depends on 8) The method of claim 8, wherein each row of the grid-like array comprises a set of serially connected capacitor plates electrically coupled to a driving line, and wherein each column of the grid-like array comprises a set of serially connected capacitor plates electrically coupled to a sensing line. ### Claim 10 A method for identifying a liquid dispensed to a surface, comprising: (a) positioning a sensor array in the vicinity of a substrate, the substrate comprising the surface to which the liquid is dispensed, the sensor comprising an array of capacitive plates arranged in a grid-like array; (b) measuring an electrical property of at least one capacitor plate responsive to alternating currents at one or more of a plurality of different frequencies; (c) identifying the liquid dispensed on the surface of the substrate that is present between the at least one pair of capacitor plates based on the measured electrical property at the one or more of the plurality of different frequencies. ### Claim 11 (depends on 10) The method of claim 10, wherein the array of capacitive plates is an array of coplanar capacitive plates. ### Claim 12 (depends on 10) The method of claim 10, wherein the array of coplanar capacitive plates are arranged in a grid-like array. ### Claim 13 (depends on 12) The method of claim 12, wherein each row of the grid-like array comprises a set of serially connected capacitive plates electrically coupled to a driving line, and wherein each column of the grid-like array comprises a set of serially connected capacitive plates electrically coupled to a sensing line. ### Claim 14 (depends on 11) The method of claim 11, wherein the electric property detected between the at least one pair of coplanar capacitive plates is one or more of a voltage, a current, a capacitance, and an impedance. ### Claim 15 A method for identifying a liquid dispensed to a surface, comprising: (a) positioning a sensor array in the vicinity of a substrate, the substrate comprising the surface to which the liquid is dispensed, the sensor comprising an array of coplanar capacitive plates; (b) measuring an electrical property of at least one capacitor plate responsive to alternating currents at one or more of a plurality of different frequencies; (c) identifying the liquid dispensed on the surface of the substrate that is present between the at least one pair of capacitor plates using a trained neural network based on the measured electrical property at the one or more of the plurality of different frequencies. ### Claim 16 (depends on 15) The method of claim 15, wherein the electric property detected between the at least one pair of coplanar capacitive plates is one or more of a voltage, a current, a capacitance, and an impedance.