Electrophoretic display with a compensation circuit for reducing a luminance difference and method thereof
An electrophoretic display includes an electrophoretic panel and a compensation circuit. The electrophoretic panel includes a common electrode, a plurality of scan lines, a plurality of data lines, a plurality of first switches, and a plurality of pixels. Each pixel of the plurality of pixels is coupled to the common electrode and coupled to a corresponding scan line and a corresponding data line through a corresponding first switch of the plurality of first switches. The compensation circuit reduces a voltage drop between a pixel voltage of the pixel and a common voltage of the common electrode when the plurality of first switches are turned off. A capacitor of the compensation circuit is coupled between each scan line and the common electrode. A second switch of the compensation circuit is turned off to float the common electrode before the plurality of first switches are turned off.
1. An electrophoretic display, comprising:
an electrophoretic panel comprising:
a common electrode;
a plurality of scan lines;
a plurality of data lines;
a plurality of first switches; and
a plurality of pixels, wherein a pixel of the plurality of pixels has a terminal coupled to the common electrode, and another terminal coupled to a corresponding scan line and a corresponding data line through a corresponding first switch of the plurality of first switches, and the pixel comprises a storage capacitor coupled between the corresponding first switch and the common electrode for storing the pixel voltage according to a data voltage of the corresponding data line when the corresponding first switch is turned on; and
a compensation circuit coupled between the common electrode of the electrophoretic panel and each scan line of the plurality of scan lines for reducing a voltage drop between a pixel voltage of the pixel and a common voltage of the common electrode when the plurality of first switches are turned off, wherein the compensation circuit comprises:
a capacitor coupled between each scan line of the plurality of scan lines and the common electrode; and
a second switch coupled to the common electrode, wherein the second switch is turned off to float the common electrode before the plurality of first switches are turned off.
2. The electrophoretic display of claim 1 , wherein the pixel further comprises a plurality of charged particles.
3. The electrophoretic display of claim 1 , wherein the plurality of first switches and the second switch are thin film transistors.
4. A method of operating an electrophoretic display, the electrophoretic display comprising an electrophoretic panel and a compensation circuit, the electrophoretic panel comprising a common electrode, a plurality of scan lines, a plurality of data lines, a plurality of first switches, and a plurality of pixels, wherein each pixel of the plurality of pixels is coupled to a corresponding first switch, and coupled to a corresponding scan line and a corresponding data line through the corresponding first switch, and the compensation circuit comprising a capacitor coupled between a corresponding scan line and the common electrode and a second switch coupled between the common electrode and a common voltage source, the method comprising:
the corresponding first switch being turned on according to a gate driving voltage of the corresponding scan line;
the pixel storing a pixel voltage according to a data voltage of the corresponding data line when the corresponding first switch is turned on;
the compensation circuit floating the common electrode by turning off the second switch before the corresponding first switch is turned off; and
the compensation circuit increasing a common voltage of the common electrode by supplying the gate driving voltage to the common electrode through the capacitor of the compensation circuit when the corresponding first switch is turned off.