# US 2017/0285872 A1 · Screen contact detection using total internal reflection > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2017/0285872 A1 - Document ID: US20170285872A1 - Status: Published application - Kind: A1 - Application number: 15/506,853 - Filed: 2014-08-27 - Published: 2017-10-05 - Earliest claimed: 2014-08-27 - Assignees: Hewlett-Packard Development Company, L.P. - Applicants: Hewlett-Packard Development Company, L.P. - Inventors: Wei-Shan YANG; Irwan HALIM - Web page: https://patentgrep.com/patent/US20170285872A1 ## CPC - G06F 3/0421: {by interrupting or reflecting a light beam, e.g. optical touch-screen} - G06F 3/0416: {Control or interface arrangements specially adapted for digitisers} - G06F 3/0428: {by sensing at the edges of the touch surface the interruption of optical paths, e.g. an illumination plane, parallel to the touch surface which may be virtual (sensing beam interruptions in a planar beam grid of an optical touch-screen G06F3/0421)} - G06F 2203/04109: FTIR in optical digitiser, i.e. touch detection by frustrating the total internal reflection within an optical waveguide due to changes of optical properties or deformation at the touch location - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) ## Abstract Examples are directed to detect screen contact using total internal reflection. One example involves detecting contact on a screen, the screen comprising total internal reflection of light; and determining, via at least one processor, a location of the contact on the screen based on a disturbance of the total internal reflection, the disturbance caused by the detected contact. ## Claims ### Claim 1 A method comprising: detecting contact on a screen comprising total internal reflection of light, the contact detected via a first light sensor and a second light sensor, the first light sensor and the second light sensor located on a first axis and a second axis of a plane of the screen, respectively, and the contact detected based on configurations of a first lens of the first light sensor and a second lens of the second light sensor, wherein the first axis is different form the second axis; and determining, via at least one processor, a location of the contact on the screen based on a disturbance of the total internal reflection, the disturbance caused by the detected contact. ### Claim 2 (depends on 1) The method as defined in claim 1, wherein the configurations of the first lens and the second lens comprise at least one of a structure of the lens, a medium of the lens, a filter of the lens, or a location of the lens. ### Claim 3 (depends on 1) The method as defined in claim 1, wherein the disturbance of the total internal reflection comprises a blockage of a light wave causing the total internal reflection. ### Claim 4 (depends on 1) The method as defined in claim 1, further comprising: analyzing a characteristic of the disturbance; and determining the contact includes a touch by a user based on the characteristic of the disturbance. ### Claim 5 (depends on 4) The method as defined in claim 4, wherein the characteristic of the disturbance comprises at least one of a length of time of the disturbance, a type of the disturbance, a size of the disturbance, or a shape of the disturbance. ### Claim 6 (depends on 1) The method as defined in claim 1, further comprising: causing the total internal reflection of light by sending a light wave into the screen. ### Claim 7 (depends on 6) The method as defined in claim 6, further comprising: adjusting an angle at which the light wave is sent into the screen based on a characteristic of the screen. ### Claim 8 An apparatus comprising: a contact analyzer to analyze light measurements from a first sensor on a first axis of a display screen and a second sensor on a second axis of the display screen to detect contact with the display screen, wherein the first axis is different from the second axis and the light measurements are made from light causing total internal reflection within the display screen; and a location calculator to determine a location of the contact on the screen based on the analyzed light measurements, the analyzed light measurements based on configurations of a first lens of the first light sensor and a second lens of the second light sensor. ### Claim 9 (depends on 7) The apparatus as defined in claim 7, wherein the contact analyzer detects a disturbance in the total internal reflection based on the light measurements. ### Claim 10 (depends on 7) The apparatus as defined in claim 7, wherein the location calculator provides the location of the contact point to a controller for control of a device. ### Claim 11 (depends on 7) The apparatus as defined in claim 7, wherein the contact analyzer comprises a filter to determine whether the contact was a touch of user. ### Claim 12 A non-transitory computer readable storage medium comprising instructions that, when executed, cause a machine to at least: analyze a total internal reflection of light within a screen to detect contact within the screen based on configurations of a first lens of a first sensor and a second lens of a second sensor, the first sensor located on a first axis of the screen and a second sensor located on a second axis of the screen to detect the contact, wherein the first axis is different form the second axis; and determine a location of the contact when the total internal reflection of light is disrupted by the contact. ### Claim 13 (depends on 12) The non-transitory computer readable storage medium of claim 12, wherein the instructions, when executed, further cause the machine to: analyze light measurements received from light sensors, wherein the light measurements indicate when the total internal reflection of light is disrupted when the light measurements are changed. ### Claim 14 (depends on 13) The non-transitory computer readable storage medium of claim 13, wherein the instructions, when executed, further cause the machine to: adjust the configurations of the first lens and the second lens based on at least one of a characteristic of the screen, an environment of the screen, or light measurements from the light sensors. ### Claim 15 (depends on 12) The non-transitory computer readable storage medium of claim 12, wherein the instructions, when executed, further cause the machine to: adjust light sources emitting light into the screen based on characteristics of the screen to cause the total internal reflection of the light.