Palpably controllable digital plate

• US 5,541,371 A
• Filed: 06/01/1993
• Issued: 07/30/1996
• Est. Priority Date: 06/01/1993
• Status: Expired due to Fees

• Current Assignee: UTEK Semiconductor Corp. (United Microelectronics Corporation)
• Original Assignee: Holtek Microelectronics, Inc. (United Microelectronics Corporation)
• Inventors: Chen, Pao F., Wang, Min K., Lu, Chau H.
• Primary Examiner(s): Chin, Stephen
• Assistant Examiner(s): LOOMIS, PAUL A
• Application Number:
  US08/069,997
• Time in Patent Office: 1,155 Days
• Field of Search: 178/15, 178/19, 178/20, 345/173, 345/174
• US Class Current: 178/18.07
• CPC Class Codes: G06F 3/044 by capacitive means
• 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

Abstract

A cost-effective and/or convenient digital plate being palpably controllable is provided. The digital plate includes an induction plate capable of inducing a change of a parameter when in contact with an object having a reactant property, a measurer for sensing the change, and a controller having an output for converting the change into a parametral information to be sent to the output.

Claims

1. A palpably controllable digital plate comprising:

an induction plate disposing therein a plurality of longitudinal metal rods and a plurality of transverse metal rods for inducing a change of a parameter when in contact with an object having a reactant property totally accounting for an induction of said change;

a resonant circuit device electrically connected to said induction plate for sensing said change;

an oscillator electrically connected to said resonant circuit device for supplying an oscillating frequency to said resonant circuit device; and

a controller electrically connected to said resonant circuit device and having an output for converting said change into a parametrial information to be sent to said output.

2. A digital plate according to claim 1 wherein said output is adapted to be electrically connnected to an interface of a computer.

3. A digital plate according to claim 1 wherein said change is induced by a plurality of said transverse and longitudinal rods being in contact with said object.

4. A digital plate according to claim 1 wherein said object is capacitive.

5. A digital plate according to claim 4 wherein said object is a finger of a person.

6. A digital plate according to claim 4 wherein said object is a capacitive pen.

7. A digital plate according to claim 1 wherein said reactant property is of a capacitive reactance.

8. A digital plate according to claim 1 wherein said parameter is reactance.

9. A digital plate according to claim 1 wherein said resonant circuit device converts said parameter into a power signal.

10. A digital plate according to claim 9 wherein said power signal is a current.

11. A digital plate according to claim 9 wherein said power signal is a voltage.

12. A digital plate according to claim 9, further comprising an analog/digital converter electrically connected between said resonant circuit device and said controller for receiving said power signal as an analog input to be converted into a digital output.

13. A digital plate according to claim 12, further comprising a multiplexer electrically connected between said induction plate and said resonant circuit device for allowing said parameter to be correctly sent to said resonant circuit device.

14. A digital plate according to claim 12 wherein said controller receives said digital output as said parametral information.

15. A digital plate according to claim 14 wherein said parametral information is representative of a particular position of said object on said induction plate.

16. A digital plate according to claim 15 wherein said particular position is disposed thereat a functional key.

17. A digital plate according to claim 14 wherein said parametral information is representative of a translation of said object on said induction plate.

18. A digital plate according to claim 17 wherein said translation is convertible into a movement of a cursor on a monitor.

19. Apparatus for indicating position on a surface comprising:

a plurality of electrically reactive elements positionally arranged in an orthogonal matrix in proximity to the surface such that finger contact with the surface changes the reactance of an element near the finger;

a source of high frequency oscillations;

a resonant circuit connected to the source, the resonant circuit having a resonant frequency near the frequency of the oscillations;

means for sequentially coupling the elements to the resonant circuit in a predetermined order to change the resonant frequency in accordance with the reactance of the coupled element;

means for sensing in the predetermined order changes in the amplitude of the oscillations caused by changes in the resonant frequency to ascertain the position of finger contact on the surface; and

means for recording the changes in amplitude.

20. The apparatus of claim 19, in which the reactive elements are capacitors.

21. The apparatus of claim 20, in which the capacitors are longitudinal and transverse metal rods.

22. The apparatus of claim 21, in which the oscillations have a fixed frequency and a constant amplitude.

23. The apparatus of claim 22, in which the recording means comprises a computer.

24. The apparatus of claim 23, in which the recording means additionally comprises a display monitor.

25. The apparatus of claim 19, in which the oscillations have a fixed frequency and a constant amplitude.

26. The apparatus of claim 19, in which the recording means comprises a computer.

27. The apparatus of claim 26, in which the recording means additionally comprises a display monitor.