Capacitive touch screen
The present invention provides a mutual capacitive multi-touch screen, which includes a guarding pattern and a conductive strip pattern exposed from each other. The conductive strip pattern includes a plurality of first conductive strips provided with a driving signal and a plurality of second conductive strips for providing mutual capacitive coupling signals, and the guarding pattern is provided with a DC signal. The guarding pattern allows that, when a touch range of each external conductive object is larger than a predetermined condition, capacitive coupling between each external conductive object and the guarding pattern or capacitive coupling between each external conductive object and the first conductive strips and the guarding pattern is greater than capacitive coupling between each external conductive object and the second conductive strips.
1. A detection method for a capacitive touch screen, comprising:
providing a capacitive touch screen, including:
a conductive strip pattern having a plurality of conductive strips exposed from each other, the conductive strip pattern including:
a plurality of first conductive strips operatively provided with a driving signal during mutual capacitive detection; and
a plurality of second conductive strips providing mutual capacitive coupling signals, the first conductive strips and the second conductive strips being exposed and separated from each other, wherein the conductive strips intersect with each other to form a grid with a plurality of exposing spaces;
a guarding pattern including a plurality of guarding conductive strips, each guarding conductive strip including a plurality of guarding connecting lines connecting a plurality of guarding conductive pads in series, wherein each space exposes at least one guarding conductive pad; and
simultaneously and continuously providing the driving signal to at least one first conductive strip, and providing a direct current (DC) signal to first conductive strips not driven by the driving signal and the guarding pattern; and
generating sensing information based on the mutual capacitive coupling signals provided by the second conductive strips each time the driving signal being provided;
wherein the conductive strip pattern allows that, when a touch area of each external conductive object on the capacitive touch screen is larger than a predetermined size, the exposed area of the guarding pattern covered by each touch area is larger than the exposed area of the second conductive strips covered by the touch area or larger than the exposed area of the conductive strip pattern covered by the touch area.
2. The detection method according to claim 1 , wherein the guarding pattern includes a plurality of upper guarding conductive strips and a plurality of lower guarding conductive strips, and the first conductive strips and the upper guarding conductive strips are adjacent to each other on the same layer, while the second conductive strips and the lower guarding conductive strips are adjacent to each other on the same layer.
3. The detection method according to claim 1 , wherein the guarding pattern includes a plurality of guarding conductive strips, and one of the first conductive strips or the second conductive strips are adjacent to the guarding conductive strips on the same layer, and the first conductive strips and the second conductive strips are disposed on different layers separated by an insulating intermediate layer.
4. The detection method according to claim 3 , wherein the guarding pattern and the first conductive strips are on the same layer, wherein the second conductive strips are on the same layer as the first conductive strips or on a layer further away from an insulating surface layer, wherein the external conductive objects approach or touch the insulating surface layer.
5. The detection method according to claim 1 , wherein capacitive coupling between each external conductive object and the second conductive strips is smaller than capacitive coupling between the external conductive object and the guarding pattern or smaller than capacitive coupling between the external conductive object and the guarding pattern and the first conductive strips.
6. The detection method according to claim 1 , wherein the predetermined condition is a width or an area, and the exposed area of the first conductive strips is greater than the exposed area of the second conductive strips.
7. The detection method according to claim 1 , wherein each value of the sensing information is the difference between a pair of second conductive strips or the difference between signal differences of two pairs of conductive strips among three conductive strips, and the difference suppresses noise coming from a display.
8. The detection method according to claim 7 , wherein the periphery of the capacitive touch screen is fixed to a display, and the portion of the capacitive touch screen not fixed to the display deforms under pressure, wherein each value of the sensing information is the difference between signal differences between the first two conductive strips and the latter two conductive strips among three conductive strips.
9. A capacitive touch screen, comprising:
a conductive strip pattern having a plurality of conductive strips exposed from each other, the conductive strip pattern including:
a plurality of first conductive strips operatively provided with a driving signal during mutual capacitive detection; and
a plurality of second conductive strips providing mutual capacitive coupling signals, the first conductive strips and the second conductive strips being exposed and separated from each other, wherein the conductive strips intersect with each other to form a grid with a plurality of exposing spaces;
a guarding pattern including a plurality of guarding conductive strips, each guarding conductive strip including a plurality of guarding connecting lines connecting a plurality of guarding conductive pads in series, wherein each space exposes at least one guarding conductive pad; and
wherein the DC signal is provided by a controller, the controller simultaneously and continuously provides the driving signal to at least one first conductive strip, and generates sensing information based on the mutual capacitive coupling signals provided by the second conductive strips each time the driving signal is provided;
wherein the conductive strip pattern allows that, when a touch area of each external conductive object on the capacitive touch screen is larger than a predetermined size, the exposed area of the guarding pattern covered by each touch area is larger than the exposed area of the second conductive strips covered by the touch area or larger than the exposed area of the conductive strip pattern covered by the touch area.
10. The capacitive touch screen according to claim 9 , wherein the guarding pattern includes a plurality of upper guarding conductive strips and a plurality of lower guarding conductive strips, and the first conductive strips and the upper guarding conductive strips are adjacent to each other on the same layer, while the second conductive strips and the lower guarding conductive strips are adjacent to each other on the same layer.
11. The capacitive touch screen according to claim 9 , wherein the guarding pattern includes a plurality of guarding conductive strips, and one of the first conductive strips or the second conductive strips are adjacent to the guarding conductive strip on the same layer, and the first conductive strips and the second conductive strips are disposed on different layers separated by an insulating intermediate layer.
12. The capacitive touch screen according to claim 11 , wherein the guarding pattern and the first conductive strips are on the same layer, wherein the second conductive strips are on the same layer as the first conductive strips or on a layer further away from an insulating surface layer, wherein the external conductive objects approach or touch the insulating surface layer.
13. The capacitive touch screen according to claim 9 , wherein capacitive coupling between each external conductive object and the second conductive strips is smaller than capacitive coupling between the external conductive object and the guarding pattern or smaller than capacitive coupling between the external conductive object and the guarding pattern and the first conductive strips.
14. The capacitive touch screen according to claim 9 , wherein the predetermined condition is a width or an area, and the exposed area of the first conductive strips is greater than the exposed area of the second conductive strips.
15. The capacitive touch screen according to claim 9 , wherein each value of the sensing information is the difference between a pair of second conductive strips or the difference between signal differences of two pairs of conductive strips among three conductive strips, and the difference suppresses noise coming from a display.
16. The capacitive touch screen according to claim 15 , wherein the periphery of the capacitive touch screen is fixed to a display, and the portion of the capacitive touch screen not fixed to the display deforms under pressure, wherein each value of the sensing information is the difference between signal differences between the first two conductive strips and the latter two conductive strips among three conductive strips.