Touch apparatus and touch sensing method

• US 8,427,442 B2
• Filed: 10/20/2009
• Issued: 04/23/2013
• Est. Priority Date: 05/27/2009
• Status: Expired due to Fees

• Current Assignee: Wintek Corporation
• Original Assignee: Wintek Corporation
• Inventors: Chang, Ting-Yu, Lai, Chih-Chang
• Primary Examiner(s): Amadiz, Rodney
• Application Number:
  US12/581,894
• Publication Number:
  US 20100302180A1
• Time in Patent Office: 1,281 Days
• Field of Search: 345156-178, 178 1801- 1811
• US Class Current: 345/173
• 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 3/04164 Connections between sensors and controllers, e.g. routing lines between electrodes and connection pads
• CPC Class Codes: G06F 3/045 using resistive elements, e.g. a single continuous surface or two parallel surfaces put in contact

Abstract

A touch apparatus including a touch panel and a touch sensing circuit is provided. The touch panel includes a first transparent substrate, a plurality of first conductive patterns, a second transparent substrate, a plurality of second conductive patterns and a plurality of spacers. The touch sensing circuit includes a first demultiplexer, a second demultiplexer, a first multiplexer, a second multiplexer, a third multiplexer, a fourth multiplexer, a fifth multiplexer, a sixth multiplexer and an analog/digital converter (ADC). The fifth multiplexer and the sixth multiplexer are used for modulating a signal receiving range of the ADC and thus the touch sensing circuit is easily judge a correctness of a sensing signal.

Claims

1. A touch apparatus, comprising:

a touch panel, comprising;

a first transparent substrate;

a plurality of first conductive patterns disposed on the first transparent substrate, being parallel to a first direction, and each of the first conductive patterns having a first end and a second end opposite to the first end along the first direction;

a second transparent substrate disposed opposite to the first transparent substrate;

a plurality of second conductive patterns disposed on the second transparent substrate, the first conductive patterns and the second conductive patterns being located between the first transparent substrate and the second transparent substrate, and each of the second conductive patterns being parallel to a second direction, wherein the first direction is intersected to the second direction, and each of the second conductive patterns has a third end and a fourth end opposite to the third end along the second direction;

a plurality of spacers disposed between the first transparent substrate and the second transparent substrate; and

a touch sensing circuit, comprising;

a first demultiplexer electrically coupled to each of the first ends for transmitting a first signal;

a second demultiplexer electrically coupled to each of the third ends for transmitting a second signal;

a first multiplexer electrically coupled to each of the third ends for receiving a first sensing signal output from each of the third ends;

a second multiplexer electrically coupled to each of the first ends for receiving a second sensing signal output from each of the first ends;

a third multiplexer electrically coupled to the first multiplexer and the second multiplexer for receiving the first sensing signal and the second sensing signal;

a fourth multiplexer electrically coupling the second ends and the fourth ends to a ground signal;

an analog/digital converter (ADC) electrically coupled to the third multiplexer for outputting a first coordinate signal and a second coordinate signal;

a fifth multiplexer electrically coupled to the ADC; and

a sixth multiplexer electrically coupled to the ADC, wherein the fifth multiplexer and the sixth multiplexer are used for modulating a signal receiving range of the ADC.

2. The touch apparatus as claimed in claim 1, wherein the touch panel further comprises:

a plurality of first electrodes, each of the first electrodes being disposed on the first end of one of the first conductive patterns, and being electrically coupled to the first demultiplexer and the second multiplexer;

a plurality of second electrodes, each of the second electrodes being disposed on the second end of one of the first conductive patterns, and being electrically coupled to the fourth multiplexer;

a plurality of third electrodes, each of the third electrodes being disposed on the third end of one of the second conductive patterns, and being electrically coupled to the second demultiplexer and the first multiplexer; and

a plurality of fourth electrodes, each of the fourth electrodes being disposed on the fourth end of one of the second conductive patterns, and being electrically coupled to the fourth multiplexer.

3. The touch apparatus as claimed in claim 2, wherein the second electrodes are electrically connected mutually.

4. The touch apparatus as claimed in claim 2, wherein the fourth electrodes are electrically connected mutually.

5. The touch apparatus as claimed in claim 1, wherein the touch panel further comprises:

a plurality of first electrodes, each of the first electrodes being disposed on the first end of one of the first conductive patterns, and being electrically coupled to the first demultiplexer and the second multiplexer;

a second electrode disposed on the second ends of the first conductive patterns to electrically connect the second ends, and the second electrode being electrically coupled to the fourth multiplexer;

a plurality of third electrodes, each of the third electrodes being disposed on the third end of one of the second conductive patterns, and being electrically coupled to the second demultiplexer and the first multiplexer; and

a fourth electrode disposed on the fourth ends of the second conductive patterns to electrically connect the fourth ends, and the fourth electrode being electrically coupled to the fourth multiplexer.

6. The touch apparatus as claimed in claim 5, wherein the second electrode and the fourth electrode are respectively a bar shape electrode.

7. A touch sensing method, used in the touch apparatus as claimed in claim 1, the touch sensing method comprising:

respectively transmitting the first signal to each of the first ends by the first demultiplexer;

sequentially electrically connecting with the third ends by the first multiplexer so as to perform a sensing on the second conductive patterns respectively, and transmitting the sensed first sensing signal to the ADC through the third multiplexer when one of the first ends is input with the first signal;

converting the first sensing signal to output the first coordinate signal by the ADC when the first sensing signal falls within the signal receiving range;

respectively transmitting the second signal to each of the third ends by the second demultiplexer;

sequentially electrically connecting the first ends by the second multiplexer so as to perform the sensing on the first conductive patterns, and transmitting the sensed second sensing signal to the ADC through the third multiplexer when one of the third ends is input with the second signal; and

converting the second sensing signal to output the second coordinate signal by the ADC when the second sensing signal falls within the signal receiving range.

8. The touch sensing method as claimed in claim 7, wherein when the first sensing signal or the second sensing signal does not fall within the signal receiving range, the ADC regards the first sensing signal or the second sensing signal as an error sensing.

9. The touch sensing method as claimed in claim 7, wherein the signal receiving range is from the first signal to the ground signal or from the second signal to the ground signal.

10. The touch sensing method as claimed in claim 9, wherein when the first multiplexer electrically connects to different one of the third ends, the signal receiving range of the ADC is different accordingly.

11. The touch sensing method as claimed in claim 9, wherein when the second multiplexer connects a different one of the first ends, the signal receiving range of the ADC is different accordingly.