TWI420206B - Electrode structure, display panel and display device - Google Patents

Description

Electrode structure, display panel and display

The invention relates to an electrode structure, in particular to a double-sided electrode structure, which can effectively reduce the variation of the penetration rate caused by the positional deviation when the double-sided electrode is in the pair. In particular, this electrode structure is suitable for high-speed liquid crystals, such as blue phase liquid crystals, and is applicable to display panels and displays.

The blue phase liquid crystal is a liquid crystal that reacts at a high speed, and the rising time and the falling time are all below 1 millisecond. High-speed liquid crystals can improve the serious motion blur of liquid crystal displays. Field Sequential Color (FSC) is a display technology that does not require the use of a color filter. The color filter is reduced, which increases the transmittance of the display panel, but must be matched with a fast response. The liquid crystal will not be slow because of the slow response of the liquid crystal, which reduces the time that the backlight can be lit and increases the complexity of the driving method. Slow liquid crystals also have different reaction times between different gray levels, resulting in mixed color errors. That is to say, if a high-speed liquid crystal can be used, the display quality and power loss of the liquid crystal display can be improved.

How to combine energy saving and environmental protection (such as not using color filters) and display quality (such as Motion Picture Response Time (MPRT)) is a problem that LCD monitors should continue to improve. If a high-speed liquid crystal (for example, a blue phase liquid crystal) can be used, a liquid crystal display having both energy saving and environmentally-friendly display quality can be realized. When a display is made of a blue phase liquid crystal, an electrode structure of In-Plane Switching (IPS) must be used. However, the blue phase liquid crystal has a problem that the driving voltage is too high and the transmittance is too low. Therefore, an electrode structure driven by a double-sided lateral electric field can be employed to drastically reduce the driving voltage.

Referring to FIG. 1 and FIG. 2, FIG. 1 is a schematic diagram of an electrode structure 1 driven by a double-sided lateral electric field; and FIG. 2 is a driving voltage and penetration when a positional shift occurs between the upper electrode 10 and the lower electrode 12. Rate diagram. As shown in FIG. 1, the electrode structure 1 includes a plurality of upper electrodes 10, a plurality of lower electrodes 12, an upper substrate 14, and a lower substrate 16. The upper substrate 14 is disposed opposite to the lower substrate 16. Each of the upper electrodes 10 is disposed on the upper substrate 14 in an equally spaced manner, and each of the lower electrodes 12 is also disposed on the lower substrate 16 in an equally spaced manner. Since the width of the electrode itself and the distance between the electrodes are very small (generally on the order of micrometers), after the upper substrate 14 and the lower substrate 16 are paired, a positional shift S is often generated between the upper electrode 10 and the lower electrode 12 (eg, the first The figure shows), which in turn causes variations in penetration. For example, assume that the width of each of the upper electrodes 10 and the width of each of the lower electrodes 12 are both 4 μm, and the spacing between each of the two upper electrodes 10 and the spacing between each of the two lower electrodes 12 are 4 μm. Then, when the positional shift S between the upper electrode 10 and the lower electrode 12 is 0 μm, 2 μm, and 4 μm, the variation in transmittance is as shown in FIG. 2 .

Therefore, one of the objects of the present invention is to provide an electrode structure, which can effectively reduce the variation of the transmittance caused by the positional deviation of the double-sided electrode in the paired group by appropriately designing the widths of the upper and lower electrodes and the spacing thereof. To solve the above problems. This electrode structure is suitable for high-speed liquid crystals, such as blue phase liquid crystals, and can be applied to display panels as well as displays.

According to an embodiment, the electrode structure of the present invention comprises a plurality of first electrodes and a plurality of second electrodes, wherein the second electrode system is disposed opposite to the first electrode. Each of the first electrodes has a first width, and each of the two adjacent first electrodes has a first pitch, wherein a ratio of the first width to the first pitch is defined as a first ratio. Each of the second electrodes has a second width, and each of the two adjacent second electrodes has a second pitch therebetween, wherein a ratio of the second width to the second pitch is defined as a second ratio. In this embodiment, the ratio of the first ratio to the second ratio is not equal to one.

According to another embodiment, the display panel of the present invention includes a first substrate, a second substrate, a plurality of first electrodes, and a plurality of second electrodes. The second substrate is disposed opposite to the first substrate. The plurality of first electrodes are disposed on the first substrate, the plurality of second electrodes are disposed on the second substrate, and the plurality of second electrodes are also disposed opposite to the plurality of first electrodes. Each of the first electrodes has a first width, and each of the two adjacent first electrodes has a first pitch, wherein a ratio of the first width to the first pitch is defined as a first ratio. Each of the second electrodes has a second width, and each of the two adjacent second electrodes has a second pitch therebetween, wherein a ratio of the second width to the second pitch is defined as a second ratio. In this embodiment, the ratio of the first ratio to the second ratio is not equal to one.

According to another embodiment, the display of the present invention comprises a display panel as described above.

In summary, the electrode structure of the present invention can effectively reduce the variation of the transmittance caused by the positional deviation of the double-sided electrode when the pair of electrodes is in the pair by appropriately designing the widths of the upper and lower electrodes and the spacing thereof. In other words, by designing the above-described electrode structure in an asymmetrical form, it is possible to greatly improve the magnitude of variation in driving voltage-transmission rate due to possible positional shift in the group.

The advantages and spirit of the present invention will be further understood from the following detailed description of the invention.

Please refer to FIG. 3 and FIG. 4, FIG. 3 is a schematic diagram of a display 3 according to an embodiment of the invention, and FIG. 4 is a schematic diagram of a pixel array 32 according to an embodiment of the invention. In practical applications, the display 3 may include a liquid crystal display panel module, a rotatable display panel module, a touch panel module, an electronic paper module, or other display modules. As shown in FIG. 3, the display 3 includes a display panel 30. In addition, display panel 30 includes a pixel array 32 as shown in FIG. The pixel array 32 includes a plurality of scan lines 34, a plurality of data lines 36, and a plurality of pixels 38. Each of the pixels 38 includes a transistor 40 and an electrode structure 42 respectively.

Please refer to FIG. 5. FIG. 5 is a schematic view showing the electrode structure 42 in FIG. 4 disposed on the substrate. As shown in FIG. 5 , the electrode structure 42 includes a plurality of first electrodes 420 and a plurality of second electrodes 422 , and the display panel 30 further includes a first substrate 424 and a second substrate 426 . The plurality of scan lines 34, the plurality of data lines 36, and the plurality of transistors 40 are included on the first substrate 424. The second substrate 426 is disposed opposite to the first substrate 424. A plurality of first electrodes 420 are disposed on the first substrate 424, and a plurality of transistors 40 are electrically connected to the plurality of first electrodes 420. A plurality of second electrodes 422 are disposed on the second substrate 426. In other words, the plurality of second electrodes 422 are also disposed opposite to the plurality of first electrodes 420. In this embodiment, the first electrode 420 and the second electrode 422 may be indium tin oxide (ITO) electrodes, and the first substrate 424 and the second substrate 426 may be transparent glass substrates, but not limited thereto.

Each of the first electrodes 420 has a first width W1, and each of the two adjacent first electrodes 420 has a first spacing L1, wherein a ratio of the first width W1 to the first spacing L1 is defined as a first The ratio R1 (ie W1/L1). Each of the second electrodes 422 has a second width W2, and each of the two adjacent second electrodes 422 has a second spacing L2, wherein the ratio of the second width W2 to the second spacing L2 is defined as a second The ratio R2 (ie W2/L2). In this embodiment, the ratio of the first ratio R1 to the second ratio R2 (ie, R1/R2) is not equal to one. Therefore, as shown in FIG. 5, even if the first substrate 424 and the second substrate 426 are in a pair, the leftmost first electrode 420 and the second electrode 422 in the figure generate a left-right positional shift S, which is specific to each other. The first electrode 420 can still be vertically aligned with the second electrode 422.

In this embodiment, the first width W1 may be between 2 and 6 micrometers, and the first pitch L1 may be between 2 and 8 micrometers, but not limited thereto. In addition, the second width W2 may be between 2 and 6 micrometers, and the second pitch L2 may be between 2 and 8 micrometers, but not limited thereto.

Please refer to FIG. 6. FIG. 6 is a schematic diagram of an embodiment of the electrode structure 42 in FIG. In this embodiment, the first width W1 of the first electrode 420 is 4 micrometers, and the first spacing L1 between every two adjacent first electrodes 420 is 6 micrometers, and the first ratio R1 is 2/. 3; the second width W2 of the second electrode 422 is 4 micrometers, and the second spacing L2 between every two adjacent second electrodes 422 is 4 micrometers, and the second ratio R2 is 1. At this time, the ratio of the first ratio R1 to the second ratio R2 is 2/3 (less than 1). As shown in FIG. 6, when the first substrate 424 and the second substrate 426 are in a pair, the leftmost first electrode 420 and the second electrode 422 in the figure are offset by 2 micrometers in the left and right positions, and every other specific distance. The first electrode 420 can also be vertically aligned with the second electrode 422 (as indicated by broken lines A and B in FIG. 6).

Please refer to FIG. 7. FIG. 7 is a schematic diagram of another embodiment of the electrode structure 42 in FIG. In this embodiment, the first width W1 of the first electrode 420 is 3 micrometers, and the first spacing L1 between every two adjacent first electrodes 420 is 4 micrometers, and the first ratio R1 is 3/. 4; the second width W2 of the second electrode 422 is 3 micrometers, and the second spacing L2 between every two adjacent second electrodes 422 is 6 micrometers, and the second ratio R2 is 1/2. At this time, the ratio of the first ratio R1 to the second ratio R2 is 3/2 (greater than 1). As shown in FIG. 7, when the first substrate 424 and the second substrate 426 are in a pair, the leftmost first electrode 420 and the second electrode 422 in the figure are shifted by 2 micrometers in the left and right positions, and every other specific distance. The first electrode 420 can also be vertically aligned with the second electrode 422 (as indicated by the broken lines C and D in FIG. 7).

It should be noted that the electrode structure 42 described above is suitable for a high speed liquid crystal such as a blue phase liquid crystal. In practical applications, a plurality of liquid crystal molecules (not shown) are disposed between the first substrate 424 and the second substrate 426. Because of the material characteristics of the blue phase liquid crystal, the surface brightness of the panel surface can be made uniform without using an optical film (for example, a color filter) other than the polarizing plate. However, as described above, if the upper and lower substrates are in the pair, The upper and lower electrodes are offset by left and right positions. In the absence of a color filter, the light emitted through the blue phase liquid crystal causes a color deviation. Therefore, by appropriately designing the widths of the upper and lower electrodes and the pitch thereof as described above, it is possible to effectively reduce the variation in the transmittance of the high-speed liquid crystal due to the positional deviation when the double-sided electrodes are in the pair.

Referring to FIG. 8, FIG. 8 is a top view of a pixel 48 including the electrode structure 42 of FIG. As shown in FIG. 5 and FIG. 8 , the first electrode 420 includes a plurality of first group electrodes 4200 and a plurality of second group electrodes 4202, and the second electrode 422 includes a plurality of third group electrodes 4220 and a plurality of fourth electrodes. The group electrode 4222, wherein the first group electrode 4200 and the second group electrode 4202 are staggered, and the third group electrode 4220 and the fourth group electrode 4222 are also staggered. It should be noted that, according to the viewing angle relationship, FIG. 8 only shows the arrangement of the first group electrode 4200 and the second group electrode 4202, the third group electrode 4220 and the fourth group electrode 4222, and the first group electrode 4200 and the second. The group electrodes 4202 are arranged in the same manner.

In an embodiment of the invention, the display panel provides a first voltage (eg, a positive voltage) to the first group electrode 4200 through the transistor 50, and a second voltage (eg, a negative voltage) through the transistor 52. Two groups of electrodes 4202. The transistors 50, 52 may be thin film transistors (TFTs). Similarly, the display panel also supplies the first voltage and the second voltage to the third group electrode 4220 and the fourth group electrode 4222 of the second electrode 422 through the two transistors. In other words, as long as a voltage difference exists between the first group electrode 4200 and the second group electrode 4202, and a voltage difference exists between the third group electrode 4220 and the fourth group electrode 4222, the liquid crystal can be driven.

Referring to FIG. 9, FIG. 9 is a schematic view showing an electrode structure 42' disposed on a substrate according to another embodiment of the present invention. The electrode structure 42' is mainly different from the electrode structure 42 described above in that the electrode structure 42' further includes a plurality of first bumps 428 and a plurality of second bumps 430. The first bumps 428 are disposed on the first substrate 424, and each of the first electrodes 420 is disposed on one of the first bumps 428. The second bumps 430 are disposed on the second substrate 426, and each of the second electrodes 422 is disposed on one of the second bumps 430. In this embodiment, the first bump 428 and the second bump 430 are made of an organic material and can be used to enhance a horizontal electric field.

Please refer to FIG. 10. FIG. 10 is a schematic view showing an electrode structure 42" disposed on a substrate according to another embodiment of the present invention. As shown in FIG. 10, the electrode structure 42" is suitable for fringe filed switching. , FFS) technology. The electrode structure 42" is mainly different from the electrode structure 42' described above in that the electrode structure 42" further includes a first common electrode 432, a second common electrode 434, a first insulating layer 436, and a second insulating layer 438. The first common electrode 432 is disposed on the first substrate 424, the first insulating layer 436 is disposed on the first common electrode 432, and the first bump 428 and the first electrode 420 are disposed on the first insulating layer 436. The second common electrode 434 is disposed on the second substrate 426, the second insulating layer 438 is disposed on the second common electrode 434, and the second bump 430 and the second electrode 422 are disposed on the second insulating layer 438. In this embodiment, the electrode structure of the present invention is applied to the edge electric field conversion technique, and the driving voltage can be further reduced. In addition, the first common electrode 432 and the second common electrode 434 may be indium tin oxide (ITO) electrodes, and the first insulating layer 436 and the second insulating layer 438 may be tantalum nitride (SiNx), but not limited thereto. . It should be noted that the edge electric field conversion technology can be easily achieved by those skilled in the art, and will not be described herein.

In another practical application of the present invention, the display panel provides a first voltage (eg, a positive voltage) to the first electrode 420 and the second electrode 422, and provides a second voltage (eg, a negative voltage) to the first common electrode 432. And a second common electrode 434. In other words, as long as there is a voltage difference between the first electrode 420 and the first common electrode 432 and a voltage difference exists between the second electrode 422 and the second common electrode 434, the liquid crystal can be driven.

Referring to FIG. 11, FIG. 11 is a schematic view showing an electrode structure 42''' disposed on a substrate according to still another embodiment of the present invention. As shown in Fig. 11, the electrode structure 42''' is suitable for Fringe Filed and In-plane Switching (FIS) technology. The first electrode 420 of the electrode structure 42 ′′′ also includes a plurality of first group electrodes 4200 and a plurality of second group electrodes 4202, and the second electrode 422 also includes a plurality of third group electrodes 4220 and a plurality of fourth group electrodes 4222, the electrode structure 42"' is mainly different from the electrode structure 42" described above in that the first group electrode 4200 and the second group electrode 4202 are staggered, and the third group electrode 4220 and the fourth group electrode 4222 are staggered.

In still another embodiment of the present invention, the display panel provides a first voltage (eg, a positive voltage) to the first group electrode 4200 and the third group electrode 4220, and provides a second voltage (eg, a negative voltage) to the second group electrode. 4202 and the fourth group of electrodes 4222, and providing a third voltage (eg, zero volts) to the first common electrode 432 and the second common electrode 434. In other words, as long as a voltage difference exists between the first group electrode 4200 and the second group electrode 4202, and a voltage difference exists between the third group electrode 4220 and the fourth group electrode 4222, the liquid crystal can be driven.

Referring to Fig. 12, Fig. 12 is a graph showing the relationship between the driving voltage and the transmittance when the first ratio R1 is 2/3 and the second ratio R2 is 1. As shown in Fig. 12, the magnitude of the drive voltage-transmission variation is very small regardless of the positional offset. In other words, it can be found from the simulation that the above-mentioned electrode structure is designed in an asymmetrical form, which can greatly improve the magnitude of the driving voltage-transmission variation caused by the positional shift which may occur when the pair is applied.

In addition, if the electrode structure of the present invention is applied to a vertical alignment (VA) liquid crystal mode, the first electrode 420 can be sandwiched between the scan line 34 and the data line 36 in FIG. 4 by 40 to 50 degrees. The second electrode 422 is also angled by 40 to 50 degrees with the scan line 34 and the data line 36 in Fig. 4, respectively. Thereby, the brightness of the liquid crystal can be made to be brightest.

Compared with the prior art, the electrode structure of the present invention can effectively reduce the variation of the transmittance due to the positional deviation when the double-sided electrode is in the pair by appropriately designing the widths of the upper and lower electrodes and the spacing thereof.

The above are only the preferred embodiments of the present invention, and all changes and modifications made to the scope of the present invention should be within the scope of the present invention.

1, 42, 42', 42", 42'''...electrode structure

3. . . monitor

10. . . Upper electrode

12. . . Lower electrode

14. . . Upper substrate

16. . . Lower substrate

30. . . Display panel

32. . . Pixel array

34. . . Sweep line

36. . . Data line

38, 48. . . Pixel

40, 50, 52. . . Transistor

420. . . First electrode

422. . . Second electrode

424. . . First substrate

426. . . Second substrate

428. . . First bump

430. . . Second bump

432. . . First common electrode

434. . . Second common electrode

436. . . First insulating layer

438. . . Second insulating layer

4200. . . First group of electrodes

4202. . . Second group electrode

4220. . . Third group electrode

4222. . . Fourth group electrode

S. . . Position offset

W1. . . First width

L1. . . First spacing

W2. . . Second width

L2. . . Second spacing

A, B, C, D. . . dotted line

Figure 1 is a schematic illustration of an electrode structure driven by a double-sided transverse electric field.

Fig. 2 is a graph showing the relationship between the driving voltage and the transmittance when a positional shift occurs between the upper electrode and the lower electrode.

Figure 3 is a schematic illustration of a display in accordance with an embodiment of the present invention.

4 is a schematic diagram of a pixel array in accordance with an embodiment of the present invention.

Fig. 5 is a schematic view showing the electrode structure in Fig. 4 disposed on a substrate.

Fig. 6 is a schematic view showing an embodiment of the electrode structure in Fig. 5.

Fig. 7 is a schematic view showing another embodiment of the electrode structure in Fig. 5.

Fig. 8 is a top view of a pixel including the electrode structure in Fig. 5.

Figure 9 is a schematic view showing an electrode structure disposed on a substrate according to another embodiment of the present invention.

Figure 10 is a schematic view showing an electrode structure disposed on a substrate according to another embodiment of the present invention.

Figure 11 is a schematic view showing an electrode structure disposed on a substrate according to still another embodiment of the present invention.

Fig. 12 is a graph showing the relationship between the driving voltage and the transmittance when the first ratio is 2/3 and the second ratio is 1.

42. . . Electrode structure

420. . . First electrode

422. . . Second electrode

424. . . First substrate

426. . . Second substrate

S. . . Position offset

W1. . . First width

L1. . . First spacing

W2. . . Second width

L2. . . Second spacing

Claims (20)

An electrode structure comprising: a plurality of first electrodes, each of the plurality of first electrodes having a first width, and a second spacing between each of the two adjacent first electrodes, the first width and The ratio of the first pitch is defined as a first ratio; and a plurality of second electrodes are disposed opposite to the plurality of first electrodes, each of the plurality of second electrodes having a second width, each adjacent to the second A plurality of second electrodes have a second pitch, and a ratio of the second width to the second pitch is defined as a second ratio; wherein a ratio of the first ratio to the second ratio is not equal to 1. The electrode structure of claim 1, wherein the first width is between 2 and 6 microns and the first spacing is between 2 and 8 microns. The electrode structure of claim 1, wherein the second width is between 2 and 6 microns and the second spacing is between 2 and 8 microns. The electrode structure of claim 1, further comprising: a first substrate, the plurality of first electrodes are disposed on the first substrate; and a second substrate disposed opposite to the first substrate, the plurality of The second electrode is disposed on the second substrate. The electrode structure of claim 4, further comprising: a plurality of first bumps disposed on the first substrate, each of the plurality of first electrodes being disposed in one of the plurality of first bumps And a plurality of second bumps disposed on the second substrate, each of the plurality of second electrodes being disposed on one of the plurality of second bumps. A display panel includes: a first substrate; a second substrate disposed opposite to the first substrate; a plurality of first electrodes disposed on the first substrate, each of the plurality of first electrodes having a first Width, a second spacing between each of the plurality of adjacent first electrodes, a ratio of the first width to the first spacing is defined as a first ratio; and a plurality of second electrodes are disposed in the first The second substrate is disposed opposite to the plurality of first electrodes, each of the plurality of second electrodes has a second width, and each second adjacent one of the plurality of second electrodes has a second spacing, the second The ratio of the width to the second pitch is defined as a second ratio; wherein the ratio of the first ratio to the second ratio is not equal to one. The display panel of claim 6, further comprising: a plurality of scan lines; a plurality of data lines; and a plurality of transistors correspondingly electrically connected to the plurality of first electrodes. The display panel of claim 6, wherein the first width is between 2 and 6 microns and the first spacing is between 2 and 8 microns. The display panel of claim 6, wherein the second width is between 2 and 6 microns and the second spacing is between 2 and 8 microns. The display panel of claim 7, wherein each of the plurality of first electrodes is respectively at an angle of 40 to 50 degrees with the scan line and the data clip, and each of the plurality of second electrodes is also respectively associated with the scan The aiming line and the data clip are 40 to 50 degrees angle. The display panel of claim 6, further comprising: a plurality of first bumps disposed on the first substrate, each of the plurality of first electrodes being disposed in one of the plurality of first bumps And a plurality of second bumps disposed on the second substrate, each of the plurality of second electrodes being disposed on one of the plurality of second bumps. The display panel of claim 6, further comprising a plurality of blue phase liquid crystal molecules disposed between the first substrate and the second substrate. The display panel of claim 6, wherein the plurality of first electrodes comprise a plurality of first group electrodes and a plurality of second group electrodes, the plurality of second electrodes comprising a plurality of third group electrodes and a plurality of fourth a group electrode, the plurality of first group electrodes are staggered with the plurality of second group electrodes, the plurality of third group electrodes are staggered with the plurality of fourth group electrodes, and the display panel provides a first voltage to the plurality a first group of electrodes and the plurality of third group electrodes, and providing a second voltage to the plurality of second group electrodes and the plurality of fourth group electrodes. The display panel of claim 13, wherein the first voltage is a positive voltage and the second voltage is a negative voltage. The display panel of claim 6, wherein the plurality of first electrodes comprise a plurality of first group electrodes and a plurality of second group electrodes, the plurality of second electrodes comprising a plurality of third group electrodes and a plurality of fourth a group electrode, the plurality of first group electrodes are staggered with the plurality of second group electrodes, the plurality of third group electrodes are staggered with the plurality of fourth group electrodes, and the display panel further comprises a first common electrode and a second common electrode disposed between the plurality of first electrodes and the first substrate, the second common electrode being disposed between the plurality of second electrodes and the second substrate, the display The panel provides a first voltage to the plurality of first group electrodes and the plurality of third group electrodes, providing a second voltage to the plurality of second group electrodes and the plurality of fourth group electrodes, and providing a third A voltage is applied to the first common electrode and the second common electrode. The display panel of claim 15, wherein the first voltage is a positive voltage, the second voltage is a negative voltage, and the third voltage is zero volts. The display panel of claim 6, further comprising a first common electrode and a second common electrode, the first common electrode being disposed between the plurality of first electrodes and the first substrate, the second common electrode Between the plurality of second electrodes and the second substrate, the display panel provides a first voltage to the plurality of first electrodes and the plurality of second electrodes, and provides a second voltage to the first share An electrode and the second common electrode. The display panel of claim 17, wherein the first voltage is a positive voltage, and the second voltage is a negative voltage or the first voltage is a negative voltage, and the second voltage is a positive voltage. A display comprising the display panel of claim 6. The display device of claim 19, comprising: a liquid crystal display panel module, a rotatable display panel module, a touch panel module, and an electronic paper module.