Method for detecting pressure of active pen, device and active pen

Patent metadata

Field	Value
Publication number	US-2019324562-A1
Application number	US-201916457790-A
Country	US
Kind code	A1
Filing date	Jun 28, 2019
Priority date	Jan 5, 2018
Publication date	Oct 24, 2019
Grant date	—

Abstract

Provided are a method for detecting a pressure of an active pen, a device and an active pen, where a pen body of the active pen is provided with a touch sensor. The method includes: obtaining a sensing change amount of the touch sensor, where the sensing change amount indicates a capacitance change amount of the touch sensor; and determining, according to the sensing change amount, a pressure value on the pen body. The technical solution provided by the disclosure can reduce the cost of the active pen while realizing the pressure detection for the active pen.

First claim

What is claimed is:

1 . A method for detecting a pressure of an active pen, a pen body of the active pen being provided with a touch sensor, wherein the method comprises:
obtaining a sensing change amount of the touch sensor, wherein the sensing change amount is used to indicate a capacitance change amount of the touch sensor; and determining, according to the sensing change amount, a pressure value received by the pen body.

2 . The method according to claim 1 , wherein the obtaining a sensing change amount of the touch sensor comprises:
obtaining a reference sensing value of the touch sensor, wherein the reference sensing value is amplitude of a voltage signal fed back by the touch sensor in response to a reference voltage signal applied thereon when the pen body is free of pressure; obtaining a current sensing value of the touch sensor, wherein the current sensing value is amplitude of a voltage signal fed back by the touch sensor in response to the reference voltage signal applied thereon at a current time; and obtaining a difference between the reference sensing value and the current sensing value as the sensing change amount of the touch sensor.

3 . The method according to claim 2 , wherein the obtaining a reference sensing value of the touch sensor comprises:
obtaining a pre-stored reference sensing value of the touch sensor.

4 . The method according to claim 3 , wherein the method further comprises:
updating the pre-stored reference sensing value of the touch sensor when the active pen is powered on or sleeping, wherein the updating the pre-stored reference sensing value of the touch sensor comprises:
obtaining the current sensing value of the touch sensor; and
updating the pre-stored reference sensing value of the touch sensor with the current sensing value when an absolute value of a difference between the current sensing value and the pre-stored reference sensing value is smaller than a preset sensing threshold.

5 . The method according to claim 2 , wherein there are a plurality of touch sensors, and the obtaining the current sensing value of the touch sensor comprises:
scanning each of the touch sensors sequentially using the reference voltage signal, and obtaining amplitude of a voltage signal fed back by each of the touch sensors.

6 . The method according to claim 1 , wherein there are a plurality of touch sensors, and the obtaining a sensing change amount of the touch sensor comprises:
obtaining the sensing change amount of each of the touch sensors separately, wherein the determining, according to the sensing change amount, a pressure value received by the pen body comprises:
calculating a sum of sensing change amounts of the touch sensors;
determining whether the sum of the sensing change amounts is greater than zero; and
determining the pressure value on the pen body according to the sensing change amounts and a preset mapping relationship if the sum of the sensing change amounts is greater than zero, wherein the mapping relationship comprises mapping information between the pressure value and the sensing change amounts of the touch sensors.

7 . The method according to claim 1 , wherein the method further comprises:
transmitting the pressure value to a touch terminal wirelessly.

8 . The method according to claim 1 , wherein the method further comprises:
controlling the active pen to enter a sleep-low-power state when a duration of the pressure value being smaller than a first pressure threshold is greater than a preset time threshold; and waking up the active pen from the sleep-low-power state to a normal working state when the pressure value is greater than a second pressure threshold.

9 . A device for detecting a pressure of an active pen, a pen body of the active pen being provided with a touch sensor, wherein the device comprises:
an obtaining module, configured to obtain a sensing change amount of the touch sensor, wherein the sensing change amount is used to indicate a capacitance change amount of the touch sensor; and a determining module, configured to determine, according to the sensing change amount obtained by the obtaining module, a pressure value received by the pen body.

10 . The device according to claim 9 , wherein the obtaining module comprises:
a first obtaining unit, configured to obtain a reference sensing value of the touch sensor, wherein the reference sensing value is amplitude of a voltage signal fed back by the touch sensor in response to a reference voltage signal applied thereon when the pen body is free of pressure; a second obtaining unit, configured to obtain a current sensing value of the touch sensor, wherein the current sensing value is amplitude of a voltage signal fed back by the touch sensor in response to the reference voltage signal applied thereon at a current time; and a first determining unit, configured to obtain a difference between the reference sensing value obtained by the first obtaining unit and the current sensing value obtained by the second obtaining unit as the sensing change amount of the touch sensor.

11 . The device according to claim 10 , wherein the device further comprises: a storage module, configured to pre-store a reference sensing value of the touch sensor; and
the first obtaining unit is specifically configured to: obtain the reference sensing value of the touch sensor pre-stored in the storage module.

12 . The device according to claim 11 , wherein the device further comprises:
an updating module, configured to update the reference sensing value of the touch sensor pre-stored in the storage module when the active pen is powered on or sleeping, wherein the updating module comprises: a third obtaining unit, configured to obtain the current sensing value of the touch sensor; and an updating unit, configured to update the reference sensing value of the touch sensor pre-stored in the storage module with the current sensing value when an absolute value of the difference between the current sensing value obtained by the third obtaining unit and the reference sensing value pre-stored in the storage module is smaller than a preset sensing threshold.

13 . The device according to claim 10 , wherein there are a plurality of touch sensors, and the second obtaining unit is specifically configured to:
scan each of the touch sensors sequentially using the reference voltage signal, and obtain amplitude of a voltage signal fed back by each of the touch sensors.

14 . The device according to claim 9 , wherein there are a plurality of touch sensors, and the obtaining module is specifically configured to:
obtain the sensing change amount of each of the touch sensors separately, wherein the determining module comprises: a calculating unit, configured to calculate a sum of sensing change amounts of the touch sensors; a determining unit, configured to determine whether the sum of the sensing change amounts as calculated by the calculating unit is greater than zero; and a second determining unit, configured to determine the pressure value on the pen body according to the sensing change amounts and a preset mapping relationship if the determining unit determines that the sum of the sensing change amounts is greater than zero, wherein the mapping relationship comprises mapping information between the pressure value and the sensing change amounts of the touch sensors.

15 . The device according to claim 9 , wherein the device further comprises:
a radio module, configured to transmit the pressure value determined by the determining module to a touch terminal wirelessly.

Assignees

• Shenzhen Goodix Tech Co Ltd

Inventors

• Yin Hailin
• Yao Zhi
• Jin Wenhe
• Liu Yufeng

Classifications

• G06F2203/0384

  Wireless input, i.e. hardware and software details of wireless interface arrangements for pointing devices · CPC title

• G06F3/0383

  Signal control means within the pointing device · CPC title

• G06F3/03545 Primary

  Pens or stylus · CPC title

• G06F3/03547

  Touch pads, in which fingers can move on a surface · CPC title

• G06F1/3296

  by lowering the supply or operating voltage · CPC title