CN102456321A

CN102456321A - Electrophoretic display and image updating method thereof

Info

Publication number: CN102456321A
Application number: CN2010105116735A
Authority: CN
Inventors: 魏嘉宏; 郭文源; 庄翔琮
Original assignee: EUREKA MICROELECTRONICS Inc
Current assignee: EUREKA MICROELECTRONICS Inc
Priority date: 2010-10-19
Filing date: 2010-10-19
Publication date: 2012-05-16

Abstract

The invention provides an electrophoretic display and an image updating method thereof. The electrophoretic display comprises a panel, a line driver which comprises a decoder, a row driver, a plurality of grid scanning lines which are connected between the line driver and the panel, a plurality of source scanning lines which are connected between the row driver and the panel, and a time sequence controller which is connected with the line driver and the row driver, wherein the decoder conducts decoding according to the initial position and the end position of a local block provided by the time sequence controller to obtain a grid scanning line corresponding to the local block, wherein the grid scanning line is driven by the line driver. When an image is updated, the grid scanning line corresponding to the local block which is required to be updated is driven only, so as to shorten image updating time and reduce image updating power consumption.

Description

Electrophoretic display device (EPD) and menu renewal method thereof

Technical field

The present invention be relevant a kind of electrophoretic display device (EPD) (ElectroPhoretic Display, EPD), particularly about the menu renewal method of a kind of EPD.

Background technology

EPD has bistable state (bistability), and the moment of the image that only changes just needs power consumption, thereby is superior to the display of other kinds in some application.But bistable state also is the shortcoming of EPD simultaneously, makes it be inappropriate for film and animation that demonstration needs Gao Gengxin speed.Therefore EPD is fit to the less application of picture change demand, for example Electronic Paper, e-book, electronics diary, electronic notebook, electronic newspaper, electronic dictionary, electronic poster, DPF and other suchlike devices.

In EPD; As shown in Figure 1; Panel 10 has many row (or selection) electrode 12 and many row (or data) electrode 14, and each bar row electrode 12 has a pixel 16 with each bar column electrode 14 intersection, thin film transistor (TFT) 18 of each pixel 16 configuration; Its grid, source electrode and drain electrode are connected row electrode 12, column electrode 14 and the pixel electrode of this pixel respectively; Therefore optionally apply voltage to this pixel, carry out electrophoretic migration, make this pixel present bright dark space branch by the ambient light principle of reflection with the charged particle that produces this pixel of electric field driven.The pixel 16 that time schedule controller 24 control row drivers 20 and line driver 22 drive on the panel 10.Controlling grid scan line of row driver 20 each selections; Make the whole pixels 16 on the row electrode 12 of its connection accept driving voltage from line driver 22 simultaneously, the driving voltage that each pixel 16 is accepted depends on the GTG value (gray level) that this pixel 16 is invested.When frame update, time schedule controller 24 receives the GTG value of each pixel 16 in the new picture, finds the mode of its driving according to new, the old GTG value of each pixel 16 again, then in proper order driving grid sweep trace A0 to An.The mode that all possible GTG value changes, be stores with key in storer, supply time schedule controller 24 to read the mode of its driving pixels.Since the method for this frame updating at every turn all in proper order driving grid sweep trace A0 therefore be difficult to improve the speed and the reduction power consumption of frame updating to An.

More specifically, with reference to Fig. 2, if picture has only local block to change, for example jump out a dialogue square 26 of confirming cancellation, but still driving grid sweep trace A0 is to An in proper order, then most of the time and power all are wasted.For example, the quantity of the controlling grid scan line that dialogue square 26 is corresponding has only whole controlling grid scan line A0 to 1/4th of An quantity, will have 75% time and power to be wasted so.Because EPD is that mat moving belt charged shows GTG, so its reaction velocity is activated the very big restriction of mode.In Fig. 2, the running time Ts of a controlling grid scan line is represented in the pulse in left side.With regard to set pixel was formed, the electrophoresis of its charged particle distance can be considered the integration of driving electric field to the time.Therefore, the glutinousness of the thickness of pixel, content, WV, GTG resolution or the like factor short operation time T s that has promptly limited a row electrode formerly in the sky.Simple estimation, if accomplish the action need time T s and the power P s of a row electrode, the renewal of then accomplishing a picture needs time (n+1) Ts and power (n+1) Ps, these two specifications are difficult to go reduction from the improvement of material or technology.Therefore in the practical application for local block frame updating, a kind of fast, the menu renewal method of low-power consumption, be to be the institute Ji.

Summary of the invention

One of the object of the invention is to propose a kind of menu renewal method fast into EPD.

One of the object of the invention is to propose for EPD a kind of menu renewal method of low-power consumption.

According to the present invention; A kind of EPD comprises that panel, row driver connect this panel, line driver through many source electrode sweep traces these panels of connection and time schedule controller this row driver of connection and this line driver through many controlling grid scan lines; Reference position and end position decoding that this row driver contains the local block that demoder provides according to this time schedule controller obtain the corresponding controlling grid scan line of this part block, accept this row driver and drive.

According to the present invention, the menu renewal method of a kind of EPD only drives its corresponding controlling grid scan line to the local block that desire is upgraded, to upgrade the picture on the panel.

Because partial update does not scan whole controlling grid scan lines, so update time is very fast, power consumption is also less.

Description of drawings

Fig. 1 shows the EPD of convention;

Fig. 2 is the synoptic diagram of EPD when frame update of convention;

Fig. 3 is the process flow diagram according to EPD frame updating of the present invention;

Fig. 4 is the EPD that can carry out method shown in Figure 3;

The synoptic diagram of Fig. 5 EPD of the present invention when the local block of frame update; And

The synoptic diagram of Fig. 6 EPD of the present invention when the local block of frame update.

Drawing reference numeral:

10 panels

12 row electrodes

14 column electrodes

16 pixels

18 thin film transistor (TFT)s

20 row drivers

22 line drivers

24 time schedule controllers

The local block of 26 pictures

28 demoders

The local block of 30 pictures

The local block of 32 pictures

Embodiment

Fig. 3 is the process flow diagram according to EPD frame updating of the present invention, and Fig. 4 is the EPD that can carry out this method.With reference to Fig. 3 and Fig. 4, step S10 receives the frame update indication, and step S12 distinguishes whether carry out local block renewal.When not carrying out local block when upgrading, general as prior art to step S14, time schedule controller 24 can drive whole controlling grid scan line A0 to An by control row drivers 20.If will carry out partial update, then select the corresponding controlling grid scan line of local block that will upgrade and drive from controlling grid scan line A0 to An.More specifically, time schedule controller 24 after receiving the picture part that will upgrade, can learn the local block 26 that will upgrade reference position (x1, y1) and end position (x2; Y2), and give row driver 20 with position y1 to y2, row driver 20 contains demoder 28, and y1 obtains the corresponding controlling grid scan line Ay1 of local block 26 to Ay2 to the y2 decoding from the position; Shown in step S16; Therefore, in step S18,20 of row drivers can driving grid sweep trace Ay1 to Ay2.As shown in Figure 5, suppose that controlling grid scan line Ay1 has only whole controlling grid scan line A0 to 1/4th of An quantity to the quantity of Ay2, the time of a frame updating and power consumption all can taper to and have only 1/4th so.Under an opposite extreme situations, the renewal of a subframe has only a controlling grid scan line to be driven.

Can know that from above-mentioned explanation the partial update of picture is not limited to a continuous block, and is for example shown in Figure 6, the local block that upgrade is 30 and 32, thus driving grid sweep trace Ay1 to Ay2 and Ay3 to Ay4.

From the viewpoint of an intuition, the demonstration of the above-mentioned similar sprite of frame updating mode, but different be, the present invention has only the controlling grid scan line that drives local block, and this is because the present invention has utilized the bistable characteristic of EPD.

With reference to Fig. 4 and Fig. 5, clearly, when frame update, have only the driving quantity of utilizing demoder 28 to reduce controlling grid scan line, other parts of system do not need to revise, so the present invention can be applied directly to existing EPD.

Because the special type of drive of EPD, its reaction velocity is lower than the display of other types.But the present invention can significantly shorten the time of EPD frame update, thereby reduces its low reaction velocity effect.

Aspect power consumption; EPD and LCD (LCD) are compared, because EPD does not need backlight, so the ratio that the power consumption of EPD when frame update accounts for its total power consumption is far above LCD; Therefore as long as EPD can reduce the required power consumption of frame update, its efficient will significantly improve.

Claims

1. an electrophoretic display device (EPD) is characterized in that, described electrophoretic display device (EPD) comprises:

Panel;

Row driver contains demoder;

Line driver;

Many controlling grid scan line is connected between said row driver and the said panel;

Many the source electrode sweep trace is connected between said line driver and the said panel; And

Time schedule controller connects said row driver and said line driver;

Wherein, said demoder obtains the corresponding controlling grid scan line of said local block according to the reference position and the end position decoding of the local block that said time schedule controller provides, and accepts said row driver and drives.

2. the menu renewal method of an electrophoretic display device (EPD) is characterized in that, said electrophoretic display device (EPD) contains panel and row driver connects said panel through many controlling grid scan lines, and said method comprises the following steps:

A, select the corresponding controlling grid scan line of local block of said panel from said many controlling grid scan lines; And

B, only drive said correspondence controlling grid scan line to upgrade said local block.

3. described method as claimed in claim 2 is characterized in that, said steps A comprises the controlling grid scan line that obtains said correspondence from the decoding of the reference position of said local block and end position.