# US 10,121,049 B2 · Fingerprint based smart phone user verification > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,121,049 B2 - Document ID: US10121049B2 - Status: Granted - Kind: B2 - Application number: 15/429,578 - Filed: 2017-02-10 - Published: 2017-08-03 - Granted: 2018-11-06 - Earliest claimed: 2013-04-01 - Assignees: AMI Research & Development, LLC - Applicants: AMI Research & Development, LLC - Inventors: John T. Apostolos; William Mouyos; Judy Feng; Dwayne T. Jeffrey; Lillian Dobrowolski - Web page: https://patentgrep.com/patent/US10121049B2 ## CPC - G06F 3/0488: using a touch-screen or digitiser, e.g. input of commands through traced gestures - G06F 3/044: by capacitive means - G06F 21/32: using biometric data, e.g. fingerprints, iris scans or voiceprints - G06V 10/17: {using hand-held instruments} - G06V 40/1306: {non-optical, e.g. ultrasonic or capacitive sensing} - G06V 40/1335: {Combining adjacent partial images (e.g. slices) to create a composite input or reference pattern; Tracking a sweeping finger movement} - G06V 40/1359: {Extracting features related to ridge properties; Determining the fingerprint type, e.g. whorl or loop} - G06V 40/1376: {Matching features related to ridge properties or fingerprint texture} - G06V 40/28: {Recognition of hand or arm movements, e.g. recognition of deaf sign language (static hand signs G06V40/113)} - G06V 40/70: Multimodal biometrics, e.g. combining information from different biometric modalities - H04L 63/0861: {using biometrical features, e.g. fingerprint, retina-scan (cryptographic mechanisms or cryptographic arrangements for entity authentication using biological data H04L9/3231)} - H04M 1/673: the user being required to key in a code - H04W 12/065: Continuous authentication - G06F 2203/0338: Fingerprint track pad, i.e. fingerprint sensor used as pointing device tracking the fingertip image - G06F 2221/2139: Recurrent verification - H04M 2250/22: including a touch pad, a touch sensor or a touch detector - H04W 12/68: Gesture-dependent or behaviour-dependent - H04W 88/02: Terminal devices - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - G06V: IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) - H04M: TELEPHONIC COMMUNICATION (circuits for controlling other apparatus via a telephone cable and not involving telephone switching apparatus G08) - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract A touchscreen, now incorporated in most smartphones, tablets, laptops, and similar devices, presents an effective and transparent method to incorporate continuous active user verification schemes. The touchscreen element grid structure can be used to capture information, such as a set of one-dimensional time-varying signals produced as the user's finger moves past the grid intersections points. This information may be used to verify the user, or that a valid user currently has possession of the mobile device, even while the user is not consciously engaged in an active verification process. Further functions, such as habitual gesture recognition, can also be performed using the same grid outputs. ## Claims ### Claim 1 A method for encoding information representative of a person's fingerprint comprising: receiving one or more outputs from a touchscreen array as the person's finger passes adjacent a corresponding one or more touch sensitive elements of touchscreen array; digitizing the one or more outputs to generate one or more corresponding one-dimensional time-varying digital signals, each digital signal comprising a sequence of digital amplitude values representative of a ridge and valley detail of a rectangular portion of the person's finger that passes adjacent the corresponding one of the touchscreen array elements as the person uses the touchscreen over time; and normalizing at least one of the sequence of digital amplitude values with respect to a velocity at which the person's finger moves. ### Claim 2 (depends on 1) The method of claim 1 additionally comprising: processing the sequence of digital amplitude values to determine a time-varying velocity signal representative of a velocity of the person's finger over time with respect to the corresponding touchscreen array element; and using the velocity signal in the step of normalizing. ### Claim 3 (depends on 1) The method of claim 1 wherein the sequence of digital amplitude values is further representative of a direction along which the person's finger moves with respect to the corresponding touchscreen array element. ### Claim 4 (depends on 1) The method of claim 1 wherein the step of normalizing further comprises: normalizing the sequence of digital amplitude values by a time scale factor that depends on the velocity at which the person's finger moves with respect to the corresponding touchscreen array element. ### Claim 5 (depends on 1) The method of claim 1 additionally comprising: converting the sequence of digital amplitude values to a corresponding image representation comprising a single row of pixel values, where each pixel value corresponds to a gray scale conversion of a corresponding digital amplitude value. ### Claim 6 (depends on 1) The method of claim 1 additionally comprising: matching the sequence of digital values in one or more of the digital signals against stored information representative of the person's fingerprint. ### Claim 7 (depends on 6) The method of claim 6 wherein the step of matching additionally comprises: rotating and/or translating a position of the sequence of digital values relative to the stored information representative of the person's fingerprint. ### Claim 8 (depends on 1) The method of claim 1 additionally comprising: detecting a touchscreen gesture from the same one or more of the one-dimensional time-varying signals; and using the touchscreen gesture for a function other than fingerprint characterization. ### Claim 9 (depends on 1) The method of claim 1 wherein a spacing between adjacent elements of the touchscreen array is at least ten times larger than a spacing between ridges of the person's fingerprint. ### Claim 10 (depends on 1) The method of claim 1 wherein the touchscreen array comprises a capacitive wire grid. ### Claim 11 A method for encoding information representative of a person's fingerprint comprising: displaying a swipe path on a touchscreen array; receiving two or more time-varying outputs from the touchscreen array as the person's finger follows the swipe path adjacent two or more elements of touchscreen array; and digitizing the two or more outputs to generate two or more corresponding one-dimensional time-varying digital signals, each time varying digital signal comprising a sequence of digital amplitude values that are representative of a ridge and valley detail of a portion of the person's finger that passes adjacent a corresponding one of the two or more touchscreen array elements. ### Claim 12 (depends on 11) The method of claim 11 wherein the swipe path is represented as a moving object on a display portion of the touchscreen. ### Claim 13 (depends on 11) The method of claim 11 additionally comprising: displaying at least one additional swipe path on the touchscreen array; receiving additional time-varying outputs as a different finger of the person follows the additional swipe path; and digitizing the additional time-varying outputs to generate two or more additional time varying digital signals, each additional time varying digital signal comprising a sequence of digital amplitude values that are representative of a ridge and valley detail of a rectangular portion of the different finger. ### Claim 14 (depends on 11) The method of claim 11 additionally comprising: converting the sequence of digital amplitude values to a corresponding image representation comprising a single row of pixel values, where each pixel value corresponds to a gray scale conversion of a corresponding digital amplitude value. ### Claim 15 (depends on 11) The method of claim 11 additionally comprising: determining whether there is a match between the detected time-varying digital signals and previously stored information that is representative of the person's fingerprint. ### Claim 16 (depends on 15) The method of claim 15 additionally comprising: when the match is found, authorizing the person to use the touchscreen; and when the match is not found, disabling use of the touchscreen. ### Claim 17 (depends on 11) The method of claim 11 additionally comprising: detecting a touchscreen gesture from two or more of the time-varying digital signals, the touchscreen gesture used for a function other than fingerprint matching. ### Claim 18 (depends on 16) The method of claim 16 additionally comprising: subsequent to when the match is found, repeatedly performing subsequent steps of determining whether there is a match between the detected time-varying digital signals and previously stored information that is representative of the person's fingerprint, to continuously authorize the person to use the touchscreen. ### Claim 19 (depends on 11) The method of claim 11 wherein a spacing between adjacent elements of the touchscreen array is at least ten times larger than a spacing between ridges of the person's fingerprint. ### Claim 20 (depends on 11) The method of claim 11 wherein the touchscreen array comprises a capacitive wire grid.