Display panel with touch pads and test signal lines
A display panel includes a plurality of touch blocks matrix-arranged and corresponding to each of two or more adjacent pixel areas of the plurality of pixel areas, and first, second, third and fourth test signal lines through which first, second, third and fourth test signals are supplied by an auto probing unit. Accordingly, not only a defect in an image output function, but also a defect in a touch sensing function can be inspected prior to a modularization process by using the first, second, third and fourth test signals.
1. A display panel comprising:
a plurality of pixel areas defined in a display area and matrix-arranged, the plurality of pixel areas corresponding to a plurality of sub-pixels;
a plurality of touch blocks matrix-arranged, each touch block corresponding to two or more adjacent pixel areas of the plurality of pixel areas;
a first test signal line conducting a first test signal received from an auto probing unit;
a second test signal line conducting a second test signal received from the auto probing unit;
a third test signal line conducting a third test signal received from the auto probing unit;
a fourth test signal line conducting a fourth test signal received from the auto probing unit; and
a plurality of routing lines, each of the routing lines connected between one of the first, second, third, and fourth test signal lines and one of the plurality of touch blocks,
wherein four touch blocks of the plurality of touch blocks adjacent along a first direction are each connected to a different one of the first, second, third, and fourth test signal lines, and
wherein four touch blocks of the plurality of touch blocks adjacent along a second direction perpendicular to the first direction are each connected to a different one of the first, second, third, and fourth test signal lines.
2. The display panel of claim 1 , wherein one of the first, second, third and fourth test signals is selected to be supplied at a first voltage level, and the others of first, second, third and fourth test signals, except the selected test signal, are supplied at a second voltage level that is different from the first voltage level.
3. The display panel of claim 2 , wherein, while identical pixel signals are supplied to a plurality of pixel electrodes corresponding to the plurality of pixel areas, the auto probing unit supplies the first, second, third and fourth test signals to the plurality of touch blocks.
4. The display panel of claim 1 , further comprising a switch unit arranged between the first, second, third and fourth test signal lines and the plurality of routing lines and comprising a plurality of test drive switches that are turned on based on a test enable signal supplied by the auto probing unit,
wherein the first, second, third and fourth test signal lines are connected to the plurality of touch blocks through turned-on test drive switches.
5. The display panel of claim 1 , further comprising first and second test pad portions arranged at opposite sides of a pad area adjacent to one side of the display area in a non-display area that is disposed outside the display area, each of the first and second test pad portion comprising pads to which the auto probing unit is connected.
6. The display panel of claim 5 , wherein the first test pad portion is arranged on a first side of the pad area and comprises pads connected to two of the first, second, third and fourth test signal lines, and
the second test pad portion is arranged on a second side of the pad area and comprises pads connected to two of the first, second, third and fourth test signal lines not connected to the first test pad portion.
7. The display panel of claim 6 , wherein each of the first, second, third and fourth test signal lines is arranged in the non-display area and has a closed loop shape surrounding a periphery of the display area.