Cordless electromagnetic induction system and method for reminding battery capacity

• US 20070008294A1
• Filed: 07/06/2005
• Published: 01/11/2007
• Est. Priority Date: 07/06/2005
• Status: Abandoned Application

• Current Assignee: Waltop International Corp.
• Original Assignee: Waltop International Corp.
• Inventors: Huang, Chia-Te, Chen, Chih-An
• Application Number:
  US11/174,639
• Publication Number:
  US 20070008294A1
• Time in Patent Office: Days
• US Class Current: 345/173
• CPC Class Codes: G06F 1/3203 Power management, i.e. event-based initiation of a power-saving mode
• CPC Class Codes: G06F 1/3262 Power saving in digitizer or tablet
• CPC Class Codes: G06F 3/03545 Pens or stylus
• CPC Class Codes: Y02D 10/00 Energy efficient computing, e.g. low power processors, power management or thermal management

Abstract

The present invention discloses a cordless electromagnetic induction system, which comprises a cordless pen and a tablet, connecting to a host. In this regards, the cordless pen comprises a battery for supplying power to the pen, a RF (radio frequency)oscillator circuit for generating radio frequency signal, representing the location and status of the pen at a central frequency, and a battery voltage detection apparatus for detecting the output voltage of the battery. The battery voltage detection apparatus commands the RF oscillator circuit for generating a signal, which central frequency is at a warning frequency, while the output voltage of the battery is lower than a critical value. The tablet comprises a tablet RF receiver for receiving RF signal from the RF oscillator circuit. The tablet informed the host for raising a low battery power warning to user while the tablet RF receiver received a signal, which central frequency is at the warning frequency.

Claims

1. A cordless electromagnetic induction system, comprising:

a cordless pen, wherein said cordless pen comprising;

a battery for supplying power to said cordless pen;

a radio frequency (RF) oscillation circuit for generating RF signal representing the location and status of said cordless pen; and

a battery voltage detection apparatus for detecting an output voltage of said battery, said RF oscillation circuit is ordered, by said battery voltage detection apparatus, to generate RF signal at a warning frequency as central frequency when said output voltage is lower than a threshold; and

a tablet, connecting to a host, wherein said tablet comprising a tablet RF receiver for receiving RF signal, representing the location and status of said cordless pen, said host was informed by said tablet for issuing a low voltage warning signal to user when received RF signal is at said warning frequency as central frequency.

2. A cordless electromagnetic induction system of claim 1, wherein said cordless pen further comprising a tip, connecting to said RF oscillation circuit, said RF oscillation circuit generates RF signal representing the status of said tip.

3. A cordless electromagnetic induction system of claim 1, wherein said cordless pen further comprising a button, connecting to said RF oscillation circuit, said RF oscillation circuit generates RF signal representing the status of said button.

4. A cordless electromagnetic induction system of claim 1, wherein said cordless pen further comprising a battery warning light, connecting to said battery voltage detection apparatus, said battery warning light is turned on by said battery voltage detection apparatus to caution user.

5. A cordless electromagnetic induction system of claim 1, wherein said RF oscillation circuit further comprising a normal RF oscillation circuit for generating RF signal at a normal frequency and a warning RF oscillation circuit for generating RF signal at a warning frequency.

6. A cordless electromagnetic induction system of claim 5, wherein said warning RF oscillation circuit consumes less power than said normal RF oscillation circuit.

7. A cordless electromagnetic induction method, comprising:

providing a cordless pen and a tablet, connecting to a host, wherein said cordless pen comprising a battery for supplying power to said cordless pen, a radio frequency (RF) oscillation circuit for generating RF signal representing the location and status of said cordless pen, and a battery voltage detection apparatus for detecting an output voltage of said battery, said tablet comprising a tablet RF receiver for receiving RF signal, representing the location and status of said cordless pen;

generating RF signal at a warning frequency as central frequency, by said RF oscillation circuit following instruction from said battery voltage detection apparatus, when said output voltage is lower than a threshold; and

issuing a low voltage warning signal to user, by said host following instruction from said tablet, when received RF signal is at said warning frequency as central frequency.

8. A cordless electromagnetic induction method of claim 7, wherein said cordless pen further comprising a tip, connecting to said RF oscillation circuit, said RF oscillation circuit generates RF signal representing the status of said tip.

9. A cordless electromagnetic induction method of claim 7, wherein said cordless pen further comprising a button, connecting to said RF oscillation circuit, said RF oscillation circuit generates RF signal representing the status of said button.

10. A cordless electromagnetic induction method of claim 7, wherein said cordless pen further comprising a battery warning light, connecting to said battery voltage detection apparatus, said battery warning light is turned on by said battery voltage detection apparatus to caution user.

11. A cordless electromagnetic induction method of claim 7, wherein said RF oscillation circuit further comprising a normal RF oscillation circuit for generating RF signal at a normal frequency and a warning RF oscillation circuit for generating RF signal at a warning frequency.

12. A cordless electromagnetic induction method of claim 11, wherein said warning RF oscillation circuit consumes less power than said normal RF oscillation circuit.

13. A cordless electromagnetic induction system, comprising:

a cordless pen, wherein said cordless pen comprising;

a battery for supplying power to said cordless pen;

a radio frequency (RF) oscillation circuit for generating RF signal at a central frequency, representing the location and status of said cordless pen, said central frequency could be switched, by said RF oscillation circuit, to one of a plurality of warning frequencies or to a special warning frequency according to what received is one of a plurality of warning signals, corresponding to said plurality of warning frequencies, or a special warning signal, corresponding to said special warning frequency; and

a battery voltage detection apparatus for detecting an output voltage of said battery, a plurality of battery voltage values correspondent to said plurality of warning signals are defined between the maximum voltage of said battery and zero voltage, said special warning signal is sent to said RF oscillation circuit when said output voltage is lower than all of said plurality of battery voltage values for generating RF signal at said special warning frequency as central frequency, one of said plurality of warning signals is sent to said RF oscillation circuit when said output voltage is higher than one of said plurality of battery voltage values, correspondent to said sent warning signal, for generating RF signal at one of said plurality of special warning frequencies, correspondent to said sent warning signal, as central frequency; and

a tablet, connecting to a host, wherein said tablet comprising a tablet RF receiver for receiving RF signal, representing the location and status of said cordless pen, said host was informed by said tablet for issuing a low voltage warning signal, representing said output voltage is higher than said battery voltage value, to user when received RF signal is at said warning frequency, correspondent to said battery voltage value, as central frequency.

14. A cordless electromagnetic induction system of claim 13, wherein said cordless pen further comprising a tip, connecting to said RF oscillation circuit, said RF oscillation circuit generates RF signal representing the status of said tip.

15. A cordless electromagnetic induction system of claim 13, wherein said cordless pen further comprising a button, connecting to said RF oscillation circuit, said RF oscillation circuit generates RF signal representing the status of said button.

16. A cordless electromagnetic induction system of claim 13, wherein said cordless pen further comprising a battery warning light, connecting to said battery voltage detection apparatus, a plurality of warning light signals, corresponding to said plurality of battery voltage values, could be displayed by said battery warning light, one of said plurality of warning light signals is displayed by said battery warning light according to said output voltage.

17. A cordless electromagnetic induction system of claim 13, wherein said low voltage warning signal is displayed as said plurality of battery voltage values.

18. A cordless electromagnetic induction method, comprising:

providing a cordless pen and a tablet, connecting to a host, wherein said cordless pen comprising a battery for supplying power to said cordless pen, a radio frequency (RF) oscillation circuit for generating RF signal at a central frequency, representing the location and status of said cordless pen, and a battery voltage detection apparatus for detecting an output voltage of said battery, wherein said central frequency could be switched, by said RF oscillation circuit, to one of a plurality of warning frequencies or to a special warning frequency according to what received is one of a plurality of warning signals, corresponding to said plurality of warning frequencies, or a special warning signal, corresponding to said special warning frequency, a plurality of battery voltage values correspondent to said plurality of warning signals are defined between the maximum voltage of said battery and zero voltage, said tablet comprising a tablet RF receiver for receiving RF signal, representing the location and status of said cordless pen;

generating RF signal at said special warning frequency as central frequency, after said RF oscillation circuit receiving said special warning signal when said output voltage is lower than all of said plurality of battery voltage values, generating RF signal at one of said plurality of special warning frequencies, correspondent to said sent warning signal, as central frequency, after said RF oscillation circuit receiving one of said plurality of warning signals when said output voltage is higher than one of said plurality of battery voltage values, correspondent to said sent warning signal; and

issuing a low voltage warning signal, representing said output voltage is higher than said battery voltage value, to user, by said host following instruction from said tablet, when received RF signal is at said warning frequency, correspondent to said battery voltage value, as central frequency.

19. A cordless electromagnetic induction method of claim 18, wherein said cordless pen further comprising a tip, connecting to said RF oscillation circuit, said RF oscillation circuit generates RF signal representing the status of said tip.

20. A cordless electromagnetic induction method of claim 18, wherein said cordless pen further comprising a button, connecting to said RF oscillation circuit, said RF oscillation circuit generates RF signal representing the status of said button.

21. A cordless electromagnetic induction method of claim 18, wherein said cordless pen further comprising a battery warning light, connecting to said battery voltage detection apparatus, a plurality of warning light signals, corresponding to said plurality of battery voltage values, could be displayed by said battery warning light, one of said plurality of warning light signals is displayed by said battery warning light according to said output voltage.

22. A cordless electromagnetic induction method of claim 18, wherein said low voltage warning signal is displayed as said plurality of battery voltage values.