Split sense lines for negative pixel conpensation
A touch panel configured to compensate for negative pixel effect is disclosed. The panel can be configured to increase a capacitive sense signal, indicative of a touching or hovering object, in order to compensate for an increase in negative capacitance when the object is poorly grounded. To perform the compensation, the panel can be configured to have split sense lines so as to increase the number of electric fringe fields forming the sense signal, thereby providing a sense signal that is substantially stronger than the negative capacitance signal. Each sense line can be split into two or more strips.
1. A touch panel comprising:
a plurality of drive lines, each drive line configured to receive a separate stimulation signal and drive the touch panel to detect an object proximate to a surface of the touch panel; and
a plurality of sense lines, each sense line divided into multiple directly adjacent and electrically separated strips continuously formed along their length and configured to increase a number of electric fringe fields formed between the stimulated drive lines and the sense lines and maintain at least a predetermined ratio between a change in mutual capacitance formed between a drive line and the sense line due to the proximate object, and a negative capacitance on the sense line due to the proximate object;
wherein the change in mutual capacitance is greater than the negative capacitance.
2. The touch panel of claim 1 , wherein the multiple strips of each sense line are connected to a same sense amplifier.
3. The touch panel of claim 1 , wherein at least two of the connected strips of a single sense line are of different widths.
4. The touch panel of claim 1 , wherein at least two of the strips of different sense lines are of different widths.
5. The touch panel of claim 1 comprising a multiplexer, wherein the strips of at least one of the sense lines are connected to the multiplexer.
6. The touch panel of claim 5 , wherein the multiplexer is configured to select one of the strips to transmit sense signals to a sense amplifier.
7. The touch panel of claim 1 , wherein each sense line is divided into at least three connected strips.
8. The touch panel of claim 1 , comprising a touch controller configured to process sense signals received from the sense lines.
9. The touch panel of claim 1 , wherein a first distance between the multiple strips of a sense line is different from a second distance between adjacent strips of different sense lines, and wherein the first distance is less than the second distance.
10. The touch panel of claim 9 , wherein the first distance is a spacing between adjacent connected strips of a same sense line.
11. The touch panel of claim 1 , wherein a width of each of strip a sense line of the plurality of sense lines is less than a distance between any two connected adjacent strips of the respective sense line.
12. The touch panel of claim 1 , wherein a first distance between the multiple strips of a sense line is different from a second distance between adjacent strips of different sense lines, and wherein the second distance is greater than a total width of a sense line of the plurality of sense lines.
13. An electronic device including the touch panel of claim 1 .