Combination touch and transducer input system and method

• US 9,182,835 B2
• Filed: 06/11/2013
• Issued: 11/10/2015
• Est. Priority Date: 10/02/2008
• Status: Active Grant

• Current Assignee: Wacom Co Limited (Wacom)
• Original Assignee: Wacom Co Limited (Wacom)
• Inventors: King-Smith, Oliver P., Smit, Bernardus H., Hadizad, Peyman
• Primary Examiner(s): PARDO, THUY N
• Application Number:
  US13/915,596
• Publication Number:
  US 20130271434A1
• Time in Patent Office: 882 Days
• Field of Search: 345/174, 345/179, 345/173, 709/250, 370/295
• US Class Current: 1/1
• CPC Class Codes: G06F 2203/04104 Multi-touch detection in digitiser, i.e. details about the simultaneous detection of a plurality of touching locations, e.g. multiple fingers or pen and finger
• CPC Class Codes: G06F 2203/04105 Pressure sensors for measuring the pressure or force exerted on the touch surface without providing the touch position
• CPC Class Codes: G06F 2203/04106 Multi-sensing digitiser, i.e. digitiser using at least two different sensing technologies simultaneously or alternatively, e.g. for detecting pen and finger, for saving power or for improving position detection
• CPC Class Codes: G06F 2203/04108 Touchless 2D- digitiser, i.e. digitiser detecting the X/Y position of the input means, finger or stylus, also when it does not touch, but is proximate to the digitiser's interaction surface without distance measurement in the Z direction
• 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 3/0416 Control or interface arrangements specially adapted for digitisers
• 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 3/04166 Details of scanning methods, e.g. sampling time, grouping of sub areas or time sharing with display driving Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally G06F3/04184
• CPC Class Codes: G06F 3/0418 for error correction or compensation, e.g. based on parallax, calibration or alignment
• CPC Class Codes: G06F 3/044 by capacitive means
• CPC Class Codes: G06F 3/0441 using active external devices, e.g. active pens, for receiving changes in electrical potential transmitted by the digitiser, e.g. tablet driving signals
• 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
• CPC Class Codes: G06F 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes
• CPC Class Codes: G06F 3/046 by electromagnetic means

Abstract

A combination touch and transducer input system is provided, which facilitates user input into an electronic system with a finger and/or a transducer (e.g., a stylus). The system includes a transducer configured to generate an electric field, and a sensor including an array of electrodes and a controller. The transducer is configured to transmit digital data, such as pen pressure data and switch status data, to the sensor. For example, the transducer comprises electronic circuitry configured to encode the digital data in a signal for transmission to the sensor. The sensor controller is configured to operate both in a touch sensing mode and in a transducer sensing mode. During the touch sensing mode, the controller determines a position of a proximate object (e.g., a finger) by capacitively sensing the object with the array of electrodes. During the transducer sensing mode, the controller determines a position of the transducer based on a signal received by the array of electrodes from the transducer, and also receives and decodes the digital data encoded in the received signal. Digital data can be encoded in a signal using any suitable digital modulation techniques, such as a Frequency-Shift Keying (FSK) technique.

Claims

1. A combination pen and touch input system, comprising:

a pen-shaped transducer; and

a sensor including an array of electrodes and a sensor controller connected to the array of electrodes, the array of electrodes including first electrodes disposed along a first direction and second electrodes disposed along a second direction different from the first direction;

wherein the pen-shaped transducer includes a pressure sensor configured to detect pressure applied to a tip of the pen-shaped transducer, a transducer controller configured to generate a signal corresponding to a pressure value detected by the pressure sensor, and an antenna configured to transmit the signal corresponding to the pressure value to the sensor,

wherein the transducer controller is further configured to format the pressure value detected by the pressure sensor in a data frame and encode the data frame pursuant to a defined encoding method to transmit the pressure value encoded by the defined encoding method with a start signal indicative of a start of the data frame via the antenna to the sensor,

wherein the sensor controller connected to the array of electrodes is configured;

(i) to supply defined signals to the first electrodes disposed along the first direction and to measure attributes of signals detected by the second electrodes disposed along the second direction, to thereby capacitively detect a non-transducer object on or near the array of electrodes, (ii) to control the array of electrodes to measure attributes of signals detected by the first and the second electrodes, to thereby detect the pen-shaped transducer on or near the array of electrodes, and (iii) to time-divisionally control the array of electrodes to switch between detecting the non-transducer object and detecting the pen-shaped transducer in an alternating manner; and

wherein the sensor controller connected to the array of electrodes is further configured to repeatedly detect attributes of signals, which are asynchronously transmitted from the pen-shaped transducer to the sensor, within a defined time period, to thereby detect the pen-shaped transducer and decode the encoded data frame.

2. The combination pen and touch input system of claim 1, wherein the object is a finger.

3. The combination pen and touch input system of claim 1, wherein the defined encoding method is selected from a group consisting of a Frequency-Shift Keying (FSK) method, Amplitude-Shift Keying (ASK) method, Phase-Shift Keying (PSK) method, and Quadrature Amplitude Modulation (QAM) method.

4. The combination pen and touch input system of claim 1, wherein the attributes of signals include one or more of a frequency, amplitude, and phase of the signals.

5. The combination pen and touch input system of claim 1, wherein the sensor controller is configured to selectively connect the first electrodes with each other to form first loops and to selectively connect the second electrodes with each other to form second loops to electromagnetically detect the pen-shaped transducer, wherein the pen-shaped transducer emits an electromagnetic signal.

6. The combination pen and touch input system of claim 1, wherein the sensor controller is configured to time-divisionally control the array of electrodes by continuously detecting the pen-shaped transducer for the defined time period upon detecting a signal transmitted from the pen-shaped transducer.

7. The combination pen and touch input system of claim 6, wherein the sensor controller is configured to:

(a) start a timer upon detecting the signal transmitted from the pen-shaped transducer and continue detecting the pen-shaped transducer until the timer expires; and

(b) re-start the timer each time upon detecting a signal from the pen-shaped transducer.

8. The combination pen and touch input system of claim 1, wherein the antenna is arranged to embody the tip of the pen-shaped transducer.

9. The combination pen and touch input system of claim 1, wherein the antenna is configured to emit RF signals according to a defined wireless communication protocol.

10. The combination pen and touch input system of claim 9, wherein the defined wireless communication protocol is a Bluetooth®

protocol.

11. A pen-shaped transducer configured to be detected by a sensor including an array of electrodes, the pen-shaped transducer comprising:

a pressure sensor configured to detect pressure applied to a tip of the pen-shaped transducer,

a transducer controller configured to generate a signal corresponding to a pressure value detected by the pressure sensor, and

an antenna configured to transmit the signal corresponding to the pressure value to the sensor,

wherein the transducer controller is further configured to;

(i) operate in sleep mode and compare the pressure value detected by the pressure sensor to a determined pressure threshold in the sleep mode;

(ii) upon determining that the detected pressure value exceeds the pressure threshold, switch from the sleep mode to awake mode, format the pressure value detected by the pressure sensor in a data frame and encode the data frame pursuant to a defined encoding method to transmit the pressure value encoded by the defined encoding method with a start signal indicative of a start of the data frame via the antenna to the sensor, and start a timer to remain in the awake mode until the timer expires; and

(iii) re-start the timer each time upon determining that the detected pressure value exceeds the pressure threshold.

12. The pen-shaped transducer of claim 11, further comprising a drive current source selected from a group consisting of a battery and a capacitor.

13. The pen-shaped transducer of claim 12, wherein the drive current source is configured to be charged with power transmitted from a powering antenna associated with the sensor.

14. The pen-shaped transducer of claim 12, wherein the drive current source is configured to be charged when the pen-shaped transducer is placed in a charging station.

15. The pen-shaped transducer of claim 12, further comprising a charging connector, wherein the drive current source is charged via said charging connector.

16. A sensor controller configured to control operation of a combination pen and touch sensor including an array of electrodes, the array of electrodes including first electrodes disposed along a first direction and second electrodes disposed along a second direction different from the first direction and being configured to receive from a pen-shaped transducer a data frame, in which data is encoded by a defined encoding method, with a start signal indicative of a start of the data frame,

wherein the sensor controller is configured:

(i) to supply defined signals to the first electrodes disposed along the first direction and to measure attributes of signals detected by the second electrodes disposed along the second direction, to thereby capacitively detect a non-transducer object on or near the array of electrodes, (ii) to control the array of electrodes to measure attributes of signals detected by the first and the second electrodes, to thereby detect a pen-shaped transducer on or near the array of electrodes, and (iii) to time-divisionally control the array of electrodes to switch between detecting the non-transducer object and detecting the pen-shaped transducer in successive sampling periods; and

wherein the sensor controller is further configured to repeatedly detect attributes of signals, which are asynchronously transmitted from the pen-shaped transducer to the sensor, within a defined time period, to thereby detect the pen-shaped transducer and decode the encoded data frame.

17. The sensor controller of claim 16, which is further configured to selectively connect the first electrodes with each other to form first loops and to selectively connect the second electrodes with each other to form second loops to electromagnetically detect the pen-shaped transducer.

18. The sensor controller of claim 16, which is further configured to time-divisionally control the array of electrodes by continuously detecting the pen-shaped transducer for the defined time period upon detecting a signal transmitted from the pen-shaped transducer.

19. The sensor controller of claim 18, which is further configured to:

(a) start a timer upon detecting the signal transmitted from the pen-shaped transducer and continue detecting the pen-shaped transducer until the timer expires; and

(b) re-start the timer each time upon detecting a signal from the pen-shaped transducer.