# US 11,112,888 B2 · Pressure sensitive stylus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,112,888 B2 - Document ID: US11112888B2 - Status: Granted - Kind: B2 - Application number: 15/567,327 - Filed: 2015-07-15 - Published: 2018-03-29 - Granted: 2021-09-07 - Earliest claimed: 2015-07-15 - Assignees: Hewlett-Packard Development Company, L.P. - Applicants: Hewlett-Packard Development Company, L.P. - Inventors: James Frenock - Web page: https://patentgrep.com/patent/US11112888B2 ## CPC - G06F 3/03545: {Pens or stylus} - G06F 3/03: Arrangements for converting the position or the displacement of a member into a coded form - G06F 3/0312: {for tracking the rotation of a spherical or circular member, e.g. optical rotary encoders used in mice or trackballs using a tracking ball or in mouse scroll wheels (tracking relative movement in co-operation with a regularly or irregularly patterned surface, e.g. as in optical mice G06F3/0317; constructional details of scroll or thumb-wheels G06F3/0362; optical rotary encoders G01D5/3473)} - G06F 3/0317: {in co-operation with a patterned surface, e.g. absolute position or relative movement detection for an optical mouse or pen positioned with respect to a coded surface} - G06F 3/033: Pointing devices displaced or positioned by the user {, e.g. mice, trackballs, pens or joysticks}; Accessories therefor (digitisers characterised by the transducing means G06F3/041) - G06F 3/03541: {Mouse/trackball convertible devices, in which the same ball is used to track the 2D relative movement} - G06F 3/0487: using specific features provided by the input device, e.g. functions controlled by the rotation of a mouse with dual sensing arrangements, or of the nature of the input device, e.g. tap gestures based on pressure sensed by a digitiser - G06F 3/04883: for inputting data by handwriting, e.g. gesture or text - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) ## Abstract In one implementation, a pressure sensitive stylus may receive, at a controller, drawing area coordinates, a stroke pressure from a voltage generated by a piezoelectric crystal, and a stylus coordinate direction from a plurality of fiber optic sensors, determine a drawing area from a wireless signal frequency corresponding to the drawing area coordinates, determine a drawing mode of a stylus stroke, wherein the drawing mode includes a stylus coordinate direction and a stylus stroke type, and transmit the drawing area and the stylus stroke. ## Claims ### Claim 1 A method for a pressure sensitive stylus, comprising: receiving at a controller within the pressure sensitive stylus: a predetermined voltage that corresponds to a pressure of a stylus stroke applied on a write tip of the pressure sensitive stylus or an erase tip of the pressure sensitive stylus, wherein the write tip of the pressure sensitive stylus is coupled to a first piezoelectric crystal that generates a first voltage when a pressure is applied on the write tip, and the erase tip of the pressure sensitive stylus is coupled to a second piezoelectric crystal that generates a second voltage when a pressure is applied on the erase tip; and a stylus coordinate direction from a plurality of fiber optic sensors in the pressure sensitive stylus; determining, by the controller, a type of the stylus stroke based on whether the predetermined voltage is the first voltage generated by the first piezoelectric crystal or the second voltage generated by the second piezoelectric crystal, wherein the type of the stylus stroke is a write stroke performed by the write tip or an erase stroke performed by the erase tip; determining, by the controller, a direction of the stylus stroke based on the stylus coordinate direction; and transmitting, by the controller, the determined type of the stylus stroke and the determined direction of the stylus stroke. ### Claim 2 (depends on 1) The method of claim 1, further comprising: receiving, at the controller, drawing area coordinates of an entire drawing area inside of which the pressure sensitive stylus is able to create the stylus stroke; determining, by the controller, the entire drawing area based on the drawing area coordinates; and determining, by the controller, the direction of the stylus stroke within the entire drawing area based on the stylus coordinate direction. ### Claim 3 (depends on 1) The method of claim 1, wherein receiving the stylus coordinate direction from the plurality of fiber optic sensors includes: determining a first coordinate component of the stylus coordinate direction by a first fiber optic sensor of the plurality of fiber optic sensors; and determining a second coordinate component of the stylus coordinate direction by a second fiber optic sensor of the plurality of fiber optic sensors. ### Claim 4 (depends on 3) The method of claim 3, wherein determining the first coordinate component and the second coordinate component of the stylus coordinate direction includes sensing the first coordinate component and the second coordinate component from the write tip of the pressure sensitive stylus. ### Claim 5 (depends on 1) The method of claim 1, comprising determining a width of the stylus stroke corresponding to the pressure of the stylus stroke. ### Claim 6 A pressure sensitive stylus, comprising: a trackball located at a first end of the pressure sensitive stylus; a first piezoelectric crystal to generate a first voltage corresponding to a pressure of a write stroke applied on the trackball; a first fiber optic sensor to sense a first coordinate component of a stylus coordinate direction, wherein the first fiber optic sensor includes a first transmitter and a first receiver; an erase head located at a second end of the pressure sensitive stylus; a second piezoelectric crystal to generate a second voltage corresponding to a pressure of an erase stroke applied on the eraser head; and a controller to receive a predetermined voltage corresponding to a pressure of a stylus stroke, determine that the stylus stroke is the write stroke performed by the trackball or the erase stroke performed by the erase head based on whether the predetermined voltage is the first voltage generated by the first piezoelectric crystal or the second voltage generated by the second piezoelectric crystal, and determine a direction of the stylus stroke based on the stylus coordinate direction. ### Claim 7 (depends on 6) The pressure sensitive stylus of claim 6, wherein the controller is to: receive drawing area coordinates of an entire drawing area inside of which the pressure sensitive stylus is able to create the stylus stroke; determine the entire drawing area based on the drawing area coordinates; and determine the direction of the stylus stroke within the entire drawing area based on the stylus coordinate direction. ### Claim 8 (depends on 6) The pressure sensitive stylus of claim 6, wherein the trackball is connected to the first piezoelectric crystal by a spring and a connecting rod. ### Claim 9 (depends on 6) The pressure sensitive stylus of claim 6, wherein the controller is to determine a width of the stylus stroke based on the pressure of the stylus stroke. ### Claim 10 (depends on 6) The pressure sensitive stylus of claim 6, wherein the eraser head is connected to the second piezoelectric crystal by a spring and a connecting rod. ### Claim 11 A pressure sensitive stylus comprising: a first piezoelectric crystal to generate a first voltage corresponding to a pressure of a write stroke applied on a write tip of the pressure sensitive stylus; a second piezoelectric crystal to generate a second voltage corresponding to a pressure of an erase stroke applied on an erase tip of the pressure sensitive stylus; a plurality of fiber optic sensors to determine a stylus coordinate direction; and a controller to: receive a predetermined voltage corresponding to a pressure of a stylus stroke, determine that the stylus stroke is the write stroke performed by the write tip or the erase stroke performed by the erase tip based on whether the predetermined voltage is the first voltage generated by the first piezoelectric crystal or the second voltage generated by the second piezoelectric crystal, and determine a direction of the stylus stroke based on the stylus coordinate direction. ### Claim 12 (depends on 11) The pressure sensitive stylus of claim 11, wherein the controller is to: receive drawing area coordinates of an entire drawing area inside of which the pressure sensitive stylus is able to create the stylus stroke; and determine the entire drawing area based on the drawing area coordinates. ### Claim 13 (depends on 12) The pressure sensitive stylus of claim 12, wherein the controller is to receive the drawing area coordinates via a wireless signal frequency. ### Claim 14 (depends on 12) The pressure sensitive stylus of claim 12, wherein the controller is to: determine the direction of the stylus stroke within the entire drawing area based on the stylus coordinate direction and the drawing area coordinates. ### Claim 15 (depends on 11) The pressure sensitive stylus of claim 11, wherein the controller is to determine a width of the stylus stroke based on the pressure of the stylus stroke.