ACTIVE STYLUS PEN AND SIGNAL TRANSMISSION METHODS FOR STYLUS PEN AND TOUCH PANEL

• US 20160162044A1
• Filed: 12/03/2015
• Published: 06/09/2016
• Est. Priority Date: 12/03/2014
• Status: Active Grant

• Current Assignee: Silicon Integrated Systems Corporation (Silicon Integrated Systems Corporation Taiwan)
• Original Assignee: Silicon Integrated Systems Corporation (Silicon Integrated Systems Corporation Taiwan)
• Inventors: CIOU, Min-Yan, Kuo, Chin-Hua, Yeh, Ying-Jyh
• Granted Patent: US 9,898,109 B2
• Time in Patent Office: Days
• CPC Class Codes: G06F 3/03545 Pens or stylus
• CPC Class Codes: G06F 3/0383 Signal control means within the pointing device
• CPC Class Codes: G06F 3/04162 for exchanging data with external devices, e.g. smart pens, via the digitiser sensing hardware
• CPC Class Codes: G06F 3/0442 using active external devices, e.g. active pens, for transmitting changes in electrical potential to be received by the digitiser

Abstract

The disclosure provides an active stylus pen and signal transmission methods for the active stylus pen and a touch panel. The stylus has a touch module, a switching module, a signal comparison module, a control module and a pressure sensing module. The stylus determines a first signal generated by a touch panel, and compares an intensity of the first signal and a reference value through a first transmission path. When the intensity of the first signal exceeds the reference value, the stylus outputs a second signal to the touch panel. After the stylus outputs the second signal to the touch panel, the stylus switches to a second transmission path from the first transmission path. The stylus outputs a header signal to the touch panel. When determining a first time sequential distribution, the stylus outputs at least one bit of a pressure signal according to a second time sequential distribution.

Claims

1. An active stylus pen, comprising:

a touch module configured to detecting a first signal;

a switching module electrically connected to the touch module and configured to selectively couple to a first transmission path or a second transmission path;

a signal comparing module configured to compare an intensity the first signal with a reference value through a first signal path and to output a second signal when the intensity of the first signal is larger than the reference value;

a control module electrically connected to the touch module and the signal comparing module and configured to output a header signal for the identification of the active stylus pen; and

a pressure sensing module configured to encoding a pressure delta into a pressure signal according to a first time sequential distribution of the first signal and output at least one bit of the pressure signal according to a second time sequential distribution of the first signal,

wherein after the signal comparing module outputs the second signal, the switching module couples to the second transmission path instead of the first transmission path and ignores a feedback signal generated when the second signal is outputted.

2. The active stylus pen according to claim 1, wherein the switching module couples to the first transmission path instead of the second transmission path when a preset time is expired after the switching module couples to the second transmission path instead of the first transmission path.

3. The active stylus pen according to claim 1, wherein the control module is further configured to determine whether a number of pulses rising in the first signal matches a reference number;

and when the number of pulses rising in the first signal matches the reference number, the control module controls the pressure sensing module to encode the pressure delta into the pressure signal.

4. The active stylus pen according to claim 3, wherein the control module is further configured to detect pulses in the second time sequential distribution and to control the pressure sensing module to output the at least one bit of the pressure signal whenever one of the pulses in the second time sequential distribution rises.

5. A signal transmission method applied to an active stylus pen and comprising:

detecting a first signal;

comparing an intensity of the first signal with a reference value through a first transmission path;

outputting a second signal when the intensity of the first signal is larger than the reference value;

coupling to a second transmission path instead of the first transmission path to ignore a feedback signal generated when the second signal is outputted;

outputting a header signal for the identification of the active stylus pen;

encoding a pressure delta into a pressure signal when a first time sequential distribution is detected in the first signal; and

outputting at least one bit in the pressure signal according to a second time sequential distribution in the first signal.

6. The signal transmission method according to claim 5, wherein when the first time sequential distribution is detected in the first signal, encoding the pressure delta into the pressure signal comprises:

determining whether a number of pulses rising in the first signal matches a reference number; and

determining that the first time sequential distribution is detected in the first signal when the number of pulses rising in the first signal matches the reference number, so as to encode the pressure delta into the pressure signal.

7. The signal transmission method according to claim 5, wherein outputting the at least one bit in the pressure signal according to the second time sequential distribution in the first signal comprises:

detecting pulses in the second time sequential distribution; and

outputting the at least one bit in the pressure signal whenever one of the pulses rises in the second time sequential distribution.

8. A signal transmission method applied to a touch panel and comprising:

outputting a first signal;

generating a coordinate according to a second signal, which is outputted by an active stylus pen according to an intensity of the first signal;

detecting a header signal indicating the active stylus pen;

outputting the first signal conforming to a first time sequential distribution in response to the header signal;

outputting the first signal conforming to a second time sequential distribution;

receiving at least one bit in a pressure signal that is outputted by the active stylus pen in response to the first signal conforming to the second time sequential distribution;

determining whether the received pressure signal is correct; and

setting a track width corresponding to the pressure signal at the coordinate when the received pressure signal is correct.

9. The signal transmission method according to claim 8, wherein when a number of outputted pulses rising in the first signal matches a reference number, the first signal conforms to the first time sequential distribution.

10. The signal transmission method according to claim 8, wherein whenever one of pulses in the second time sequential distribution rises, the at least one bit in the pressure signal is received.