Electromagnetic Manuscript Input Apparatus And Method Thereof

• US 20100108410A1
• Filed: 11/03/2008
• Published: 05/06/2010
• Est. Priority Date: 11/03/2008
• Status: Active Grant

• Current Assignee: Wacom Co Limited (Wacom)
• Original Assignee: Waltop International Corp.
• Inventors: Yeh, Chia-Jui
• Granted Patent: US 8,124,892 B2
• Time in Patent Office: Days
• US Class Current: 178/18.70
• CPC Class Codes: G06F 3/03545 Pens or stylus
• CPC Class Codes: G06F 3/046 by electromagnetic means

Abstract

An electromagnetic manuscript input apparatus and a method thereof are provided for providing a manuscript input function. The electromagnetic manuscript input apparatus includes an electromagnetic pen and a digitizer. The electromagnetic pen includes a winding, a capacitor, and a circuit board. The electromagnetic pen is a pen shaped input apparatus capable of emitting electromagnetic waves, which can be either an active type having a power supply or a passive type having no power supply. The digitizer includes a plurality of antennas and windings orthogonally distributed for inducing the electromagnetic waves of the electromagnetic pen. According to the electromagnetic manuscript input method, a controller of the digitizer is used to perform a whole region scanning process to find out a position of a winding having a maximum induction potential, and further find out positions of two immediately adjacent windings.

Claims

1. An electromagnetic manuscript input method, applicable for an electromagnetic manuscript input apparatus comprising an electromagnetic pen and a digitizer to obtain coordinates of the electromagnetic pen on the digitizer, the electromagnetic manuscript input method comprising:

emitting a driving control signal by a coordinate controller of the digitizer, to drive a driving circuit of the digitizer, thus emitting a driving signal by the driving circuit to one of a plurality of horizontal windings and one of a plurality of vertical windings of the digitizer, wherein the horizontal windings are parallel arranged along a horizontal direction of the digitizer, and the vertical windings are parallel arranged along a vertical direction of the digitizer;

detecting an induction potential with a detection circuit of the digitizer, wherein the induction potential is generated according to an induction of the driven horizontal winding or the driven vertical winding to an electromagnetic wave emitted by from the electromagnetic pen;

converting the induction potential into a digital signal with an analog-to-digital (ADC) converter, and transmitting the digital signal to the coordinate controller, wherein the coordinate controller comprises a processor;

recording the digital signal by the processor in the coordinate controller, and transmitting another driving control signal to another horizontal winding or another vertical winding;

performing a detection and conversion operation with the detection circuit and the ADC, to generate another digital signal and transmit the another digital signal to the coordinate controller;

comparing the digital signal with the another digital signal to find out a larger one, and recording the larger one of the digital signal and the another digital signal, by the processor of the coordinate controller;

transmitting another different driving control signal by the coordinate controller, and performing a detection and conversion operation to the another different driving control signal with the detection circuit and the ADC, to generate a digital signal corresponding to the another different driving control signal, and comparing the digital signal corresponding to the another different driving control signal with the recorded larger one of the digital signal and the another digital signal to find out a larger one therebetween serving as an updated larger one digital signal until all of the horizontal windings and the vertical windings have been conducted with such driving operations;

setting the horizontal winding and the vertical winding which correspond to the finally updated larger one digital signal after all of the horizontal windings and the vertical windings have been conducted with such driving operations as the horizontal winding and the vertical winding having a maximum induction potential, by the processor of the coordinate controller, and recording a maximum horizontal position and a maximum vertical position corresponding the horizontal winding and the vertical winding having the maximum induction potential to the with the processor;

obtaining two adjacent horizontal positions and two adjacent vertical positions, immediately adjacent to the maximum horizontal position and the maximum vertical position, respectively, and recording the three horizontal positions and the three vertical positions with the processor;

emitting corresponding driving signals according to the three horizontal positions and the three vertical positions by the processor of the coordinate controller, and recording six corresponding induction potentials with the processor; and

calculating the coordinates of the electromagnetic pen with a coordinate algorithm corresponding to a Gauss distribution function of the induction potentials, wherein the coordinate algorithm comprises log, multiply, and add operations.

2. The electromagnetic manuscript input method according to claim 1, wherein the electromagnetic pen comprises a winding, a capacitor, and a circuit board, for emitting the electromagnetic wave.

3. The electromagnetic manuscript input method according to claim 1, wherein the electromagnetic pen comprises a battery for providing a power to the electromagnetic pen.

4. The electromagnetic manuscript input method according to claim 1, wherein the coordinate algorithm is realized by a corresponding calculation software program executed by the processor of the coordinate controller.

5. The electromagnetic manuscript input method according to claim 1, wherein the digitizer further comprises a frequency counter, for counting an amount of induction potentials processed by the detection circuit, and outputting a notification signal to the coordinate controller when all of the windings have been scanned, so as to allow the coordinate controller reconfirming to avoid misoperation.

6. The electromagnetic manuscript input method according to claim 1, wherein the coordinate algorithm is realized by a log circuit and an operational circuit.

7. An electromagnetic manuscript input apparatus, comprising:

an electromagnetic pen, for emitting an electromagnetic wave, the electromagnetic pen comprises a winding, a capacitor, and a circuit board; and

a digitizer, comprising;

a plurality of horizontal windings, parallel arranged along a horizontal direction of the digitizer, for inducing the electromagnetic wave emitted by the electromagnetic pen and generating a corresponding induction potential;

a plurality of vertical windings, parallel arranged along a vertical direction of the digitizer, for inducing the electromagnetic wave emitted by the electromagnetic pen and generating a corresponding induction potential;

a coordinate controller, comprising a processor, wherein the processor emits a driving control signal for performing a scanning operation to one of the horizontal windings or one of the vertical windings;

a detection circuit, for detecting an induction potential of the one of the horizontal windings or one of the vertical windings which is driven by the driving control signal;

an analog-to-digital (ADC) converter for receiving the detected induction potential, and converting the detected induction potential into a digital signal, and transmitting the digital signal to the coordinate controller;

a frequency counter, for counting an amount of induction potentials processed by the detection circuit, and outputting a notification signal to the coordinate controller when all of the windings have been scanned, so as to allow the coordinate controller reconfirming to avoid misoperation;

a log circuit, for receiving the digital signal from the ADC, and performing a log calculation to generate a log signal when an enabling signal inputted by the coordinate controller is at a high level, and stopping the log calculation when the enabling signal is at a low level; and

an operational circuit, for receiving a log signal from the log circuit to perform operations comprising multiply, add, and divide operations, to obtain the coordinates of the electromagnetic pen on the digitizer,

wherein the coordinate controller is adapted for emitting an enabling signal having a low level to the log circuit before the completion of scanning operation to all of the horizontal windings and vertical windings, emitting an enabling signal having a high level to the log circuit after the completion of scanning operation to all of the horizontal windings and vertical windings, and

wherein, during the scanning operation, the coordinate controller compares values of digital signals inputted from the ADC, for finding out a position of a horizontal winding having a maximum induction potential and positions of two horizontal windings immediately adjacent to the horizontal winding having the maximum induction potential, and further finding out a position of a vertical winding having a maximum induction potential and positions of two vertical windings immediately adjacent to the vertical winding having the maximum induction potential,

thus obtaining the coordinates of the electromagnetic pen on the digitizer by calculating a corresponding coordinate algorithm of a Gauss distribution function with the log circuit, and the operational circuit.

8. The electromagnetic manuscript input apparatus according to claim 7, wherein the coordinate algorithm comprises multiply, add, and divide operations.

9. The electromagnetic manuscript input apparatus according to claim 7, wherein the digitizer further includes a nonvolatile memory, for storing a software program executable by the coordinate controller.

10. An electromagnetic manuscript input apparatus, comprising:

an electromagnetic pen, for emitting an electromagnetic wave, the electromagnetic pen comprises a winding, a capacitor, and a circuit board; and

a digitizer, comprising;

a plurality of horizontal windings, parallel arranged along a horizontal direction of the digitizer, for inducing the electromagnetic wave emitted by the electromagnetic pen and generating a corresponding induction potential;

a plurality of vertical windings, parallel arranged along a vertical direction of the digitizer, for inducing the electromagnetic wave emitted by the electromagnetic pen and generating a corresponding induction potential;

a coordinate controller, comprising a processor, wherein the processor emits a driving control signal for performing a scanning operation to one of the horizontal windings or one of the vertical windings;

a detection circuit, for detecting an induction potential of the one of the horizontal windings or one of the vertical windings which is driven by the driving control signal;

an analog-to-digital (ADC) converter for receiving the detected induction potential, and converting the detected induction potential into a digital signal, and transmitting the digital signal to the coordinate controller; and

a frequency counter, for counting an amount of induction potentials processed by the detection circuit, and outputting a notification signal to the coordinate controller when all of the windings have been scanned, so as to allow the coordinate controller reconfirming to avoid misoperation,

wherein the coordinate controller is adapted for emitting an enabling signal having a low level to the log circuit before the completion of scanning operation to all of the horizontal windings and vertical windings, emitting an enabling signal having a high level to the log circuit after the completion of scanning operation to all of the horizontal windings and vertical windings, and

wherein, during the scanning operation, the coordinate controller compares values of digital signals inputted from the ADC, for finding out a position of a horizontal winding having a maximum induction potential and positions of two horizontal windings immediately adjacent to the horizontal winding having the maximum induction potential, and further finding out a position of a vertical winding having a maximum induction potential and positions of two vertical windings immediately adjacent to the vertical winding having the maximum induction potential,

thus obtaining the coordinates of the electromagnetic pen on the digitizer by calculating a corresponding coordinate algorithm of a Gauss distribution function.

11. The electromagnetic manuscript input apparatus according to claim 10, wherein the coordinate algorithm comprises multiply, add, and divide operations.