SLEW RATE AND SHUNTING CONTROL SEPARATION

• US 20120162121A1
• Filed: 12/22/2010
• Published: 06/28/2012
• Est. Priority Date: 12/22/2010
• Status: Abandoned Application

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Chang, Shih Chang, Bae, Hopil, Yu, Cheng Ho, Al-Dahle, Ahmad, Jamshidi Roudbari, Abbas
• Application Number:
  US12/976,909
• Publication Number:
  US 20120162121A1
• Time in Patent Office: Days
• US Class Current: 345/174
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• 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 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes
• CPC Class Codes: G06F 3/045 using resistive elements, e.g. a single continuous surface or two parallel surfaces put in contact

Abstract

Setting a slew rate, e.g., a rising time or a falling time, of a scanning signal can be performed with a first operation, and a shunting resistance of the scanning line can be set with a second operation. A scanning system that scans a display screen, a touch screen, etc., can set a desired slew rate during a first period of time and can set a desired shunting resistance during a second period of time. A gate line system can sequentially scan gate lines to display an image during a display phase of a touch screen. The gate line system can, for example, increase the falling times of gate line signals. After the falling gate line signal has stabilized, for example, the gate line system can decrease the shunting resistance of the gate line.

Claims

1. A scanning system comprising:

a plurality of scan lines;

a first transistor and a second transistor that each controls a first scanning signal of a first scan line, wherein the first transistor controls one of a rising time and a falling time of the first scanning signal, and the second transistor controls the other of the rising time and the falling time of the first scanning signal; and

a third transistor that controls a first shunting operation of the first scan line.

2. The scanning system of claim 1, wherein the rising time is controlled during a first time period, the falling time is controlled during a second time period, and the first shunting operation is controlled during a third time period, the first, second, and third time periods being non-overlapping time periods.

3. The scanning system of claim 1, wherein the second transistor and the third transistor are connected in parallel to the first scan line.

4. The scanning system of claim 1, further comprising:

a fourth transistor and a fifth transistor that each controls a second scanning signal of a second scan line, wherein the fourth transistor controls one of a rising time and a falling time of the second scanning signal, and the fifth transistor controls the other of the rising time and the falling time of the second scanning signal; and

a sixth transistor that controls a first shunting operation of the second scan line.

5. The scanning system of claim 4, wherein one of the rising time and the falling time of the second scanning signal is based on the first scanning signal.

6. The scanning system of claim 1, further comprising:

a third scan line, wherein an order of scanning includes scanning the first scan line with the first scanning signal, scanning the third scan line with a third scanning signal, and scanning the second scan line with the second scan signal.

7. The scanning system of claim 1, wherein a shunting resistance of the third transistor is lower than a shunting resistance of the second transistor.

8. The scanning system of claim 7, wherein the plurality of scan lines include gate lines of a touch screen.

9. The scanning system of claim 1, further comprising:

a fourth transistor that controls a second shunting operation of the first scan line.

10. The scanning system of claim 9, wherein the second transistor and the third transistor connect, in parallel, the first scan line to a first signal line, and the first transistor and the fourth transistor connect, in parallel, the first scan line to a second signal line.

11. The scanning system of claim 1, wherein the third transistor controls the first shunting operation after the second transistor controls the one of the rising time and the falling time, the first shunting operation beginning after the first scanning signal has reached a steady state.

12. A method of scanning a plurality of scan lines, the method comprising:

connecting a first voltage line to a first scan line through a first switch, the first voltage line carrying a first voltage, such that a first scan line voltage approaches the first voltage;

disconnecting the first voltage line from the first scan line;

connecting the first scan line to a second voltage line through a second switch, the second voltage line carrying a second voltage, and the second switch having a first electrical resistance, such that the first scan line voltage approaches the second voltage;

connecting, after a first predetermined time after connecting the first scan line to the second voltage line through the second switch, the first scan line to the second voltage line through a third switch having a second electrical resistance.

13. The method of claim 12, wherein the first electrical resistance is greater than the second electrical resistance.

14. The method of claim 12, wherein the first predetermined time is based on a scanning signal of another scan line of the plurality of scan lines.

15. The method of claim 12, further comprising:

connecting the first voltage line to a second scan line through a fourth switch, such that a second scan line voltage approaches the first voltage;

disconnecting the first voltage line from the second scan line;

connecting the second scan line to the voltage line through a fifth switch, the fifth switch having a third electrical resistance, such that the second scan line voltage approaches the second voltage;

connecting, after a second predetermined time after connecting the second scan line to the second voltage line, the second scan line to the second voltage line through a sixth switch having a fourth electrical resistance.

16. The method of claim 15, wherein one of a rising time and a falling time of the second scanning signal is based on the first scanning signal.

17. The method of claim 12, further comprising:

connecting a third scan line to the first voltage line, wherein an order of connecting includes connecting the first scan line to the first voltage line, connecting the third scan line to the first voltage line, and connecting the second scan line to the first voltage line.

18. The method of claim 12, wherein the second electrical resistance is lower than the first electrical resistance.

19. The method of claim 12, further comprising:

connecting, after a second predetermined time after connecting the first scan line to the first voltage line, the first scan line to the first voltage line through a fourth switch having a third electrical resistance.

20. The method of claim 12, wherein first predetermined time is greater than a time required for the first scan line voltage to reach the second voltage.

21. A computer-readable storage medium storing computer-executable instructions, the instructions executable to perform a method of scanning a plurality of scan lines, the method comprising:

connecting a first voltage line to a first scan line through a first switch, the first voltage line carrying a first voltage, such that a first scan line voltage approaches the first voltage;

disconnecting the first voltage line from the first scan line;

connecting the first scan line to a second voltage line through a second switch, the second voltage line carrying a second voltage, and the second switch having a first electrical resistance, such that the first scan line voltage approaches the second voltage;

connecting, after a first predetermined time after connecting the first scan line to the second voltage line through the second switch, the first scan line to the second voltage line through a third switch having a second electrical resistance.

22. The storage medium of claim 21, wherein the first electrical resistance is greater than the second electrical resistance.

23. The storage medium of claim 21, wherein the first predetermined time is based on a scanning signal of another scan line of the plurality of scan lines.

24. The storage medium of claim 21, the method further comprising:

connecting the first voltage line to a second scan line through a fourth switch, such that a second scan line voltage approaches the first voltage;

disconnecting the first voltage line from the second scan line;

connecting the second scan line to the voltage line through a fifth switch, the fifth switch having a third electrical resistance, such that the second scan line voltage approaches the second voltage;

connecting, after a second predetermined time after connecting the second scan line to the second voltage line, the second scan line to the second voltage line through a sixth switch having a fourth electrical resistance.

25. The storage medium of claim 21, the method further comprising:

connecting, after a second predetermined time after connecting the first scan line to the first voltage line, the first scan line to the first voltage line through a fourth switch having a third electrical resistance.