CAPACITIVE TOUCH SCREEN

• US 20140362036A1
• Filed: 12/06/2013
• Published: 12/11/2014
• Est. Priority Date: 06/06/2013
• Status: Abandoned Application

• Current Assignee: FocalTech Systems Co.,Ltd
• Original Assignee: FocalTech Systems Co.,Ltd
• Inventors: Mo, Lianghua, Ouyang, Guang
• Application Number:
  US14/099,277
• Publication Number:
  US 20140362036A1
• Time in Patent Office: Days
• US Class Current: 345/174
• CPC Class Codes: G06F 3/04164 Connections between sensors and controllers, e.g. routing lines between electrodes and connection pads
• CPC Class Codes: G06F 3/04166 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 3/04182 Filtering of noise external to the device and not generated by digitiser components
• CPC Class Codes: G06F 3/044 by capacitive means

Abstract

A capacitive touch screen is provided, which includes: a transparent cover lens; multiple sensing electrodes disposed on a surface of the transparent cover lens and arranged into a two-dimensional array; and a touch control chip bonded onto the surface of the transparent cover lens, the touch control chip being connected with each of the multiple sensing electrodes via a wire. The capacitive touch screen may decrease errors caused by the transmission of noises between electrodes in the prior art on the premise of implementing multi-ouch, thus significantly improving signal-to-noise ratio (SNR).

Claims

1. A capacitive touch screen, comprising:

a transparent cover lens;

a plurality of sensing electrodes disposed on a surface of the transparent cover lens, and arranged into a two-dimensional array; and

a touch control chip bonded onto the surface of the transparent cover lens, the touch control chip being connected with each of the plurality of sensing electrodes via a wire.

2. The capacitive touch screen according to claim 1, further comprising a flexible printed circuit connected with the touch control chip, the touch control chip and the flexible printed circuit being bonded onto the surface of the transparent cover lens via an anisotropic conductive film.

3. The capacitive touch screen according to claim 2, wherein the transparent cover lens is provided with a view area.

4. The capacitive touch screen according to claim 3, further comprising a light shielding layer disposed outside the view area of the transparent cover lens.

5. The capacitive touch screen according to claim 4, wherein the plurality of the sensing electrodes are disposed on a lower surface of the transparent cover lens, the touch control chip and the flexible printed circuit are disposed on the lower surface of the transparent cover lens outside the view area, and the light shielding layer is disposed on the lower surface of the transparent cover lens and located above the touch control chip and the flexible printed circuit.

6. The capacitive touch screen according to claim 4, further comprising a transparent film covering an upper surface of the transparent cover lens.

7. The capacitive touch screen according to claim 6, wherein the plurality of the sensing electrodes are disposed on the lower surface of the transparent cover lens, the touch control chip and the flexible printed circuit are disposed on the lower surface of the transparent cover lens outside the view area, and the light shielding layer is disposed on a lower surface of the transparent film.

8. The capacitive touch screen according to claim 6, wherein the transparent film is adhered to the transparent cover lens via a whole piece of optical clear adhesive, or the transparent film is adhered to the transparent cover lens via double sided adhesive.

9. The capacitive touch screen according to claim 6, wherein the light shielding layer is made of ink in various colors, or a light shielding material capable of being combined with the transparent cover lens or the transparent film.

10. The capacitive touch screen according to claim 6, wherein the transparent film is a polyethylene terephthalate film, a polycarbonate film or a polymethyl methacrylate film.

11. The capacitive touch screen according to claim 1, wherein the touch control chip is adapted to detect a self-capacitance of each of the sensing electrodes.

12. The capacitive touch screen according to claim 11, wherein the touch control chip is adapted to detect the self-capacitance of each of the sensing electrodes by:

driving the sensing electrodes with a voltage source or a current source; and

detecting a voltage, a frequency or an electrical quantity on each of the sensing electrodes.

13. The capacitive touch screen according to claim 11, wherein the touch control chip is adapted to detect the self-capacitance of each of the sensing electrodes by:

driving and detecting the sensing electrodes, and driving the rest of the sensing electrodes simultaneously, wherein a signal for driving the sensing electrodes and a signal for driving the rest of the sensing electrodes are a same voltage or current signal, or different voltage or current signal;

or

driving and detecting the sensing electrodes, and driving sensing electrodes peripheral to the driven sensing electrode simultaneously, wherein a signal for driving the sensing electrodes and a signal for driving sensing electrodes peripheral to the driven sensing electrode are a same voltage or current signal, or different voltage or current signals.

14. The capacitive touch screen according to claim 11, wherein the touch control chip is adapted to detect the self-capacitance of each of the sensing electrodes by:

detecting all of the sensing electrodes simultaneously;

or

detecting the sensing electrodes group by group.

15. The capacitive touch screen according to claim 11, wherein the touch control chip is adapted to determine a touch position according to a two-dimensional sensing array.

16. The capacitive touch screen according to claim 11, wherein the capacitive touch screen comprises a plurality of touch control chips bonded onto the transparent cover lens, wherein each touch control chip is adapted to detect a corresponding part of the plurality of sensing electrodes.