KR100389827B1 - Magnetic fluid display panel - Google Patents

Abstract

PURPOSE: A magnetic fluid display panel is provided to produce a display panel that has rapid response characteristic and displays motion pictures. CONSTITUTION: A magnetic fluid display panel includes a front plate(10) and a back plate(20) having a specific distance therebetween, the first electrodes(21) arranged on the back plate in the first direction, and the second electrodes(22) arranged in a direction perpendicular to the first direction and electrically insulated from the first electrodes. The display panel further includes a pixel electrode(24) and a magnetic fluid(30). The pixel electrode is formed each of the intersections of the first and second electrodes and has a light transmission region. The pixel electrode is electrically connected to adjacent first and second electrodes to form an electric field. The magnetic fluid is formed on the back plate to a predetermined thickness.

Description

Magnetic fluid display panel

The present invention relates to a magnetic fluid display panel and to a magnetic fluid display panel having high responsiveness and easy manufacturing.

As a display device, it is developed from a cathode ray tube (CRT) using an accelerated electron beam, and is being developed into a plasma display panel (PDP) using plasma discharge, or a liquid crystal display (LCD) using liquid crystal of electro-optic effect. In addition to VFD (vaccum fluorescent display) using an electron beam accelerated at low speed, and ELD (electro luminescent display) using an electroluminescent device, there are magnetic fluid display panels using magnetic fluid. These display apparatuses are classified into active display apparatuses that emit light by themselves and non-active display apparatuses that require a separate light source because they do not emit light by themselves.

Recently, LCDs used in notebook computers and the like are typical display devices of non-active light-emitting display devices, and are widely applied to small electronic products as well as notebook computers because of their low lightness and low power consumption. While such LCDs have the above advantages, they use liquid crystals and have a drawback of having to rely on demanding manufacturing processes. In particular, since the air bubbles should not remain in the liquid crystal layer existing between the front plate and the back plate maintaining a constant interval, for example, liquid crystals are injected by a difficult vacuum injection method using vacuum differential pressure. Thus, for the liquid crystal injected in the vacuum state by the vacuum injection method, the cavity of the unit LCD must be separated by a partition of a constant width, so that when a display device for a large screen is manufactured with a plurality of unit LCDs, a partition of a constant width is produced. As a result, the junction between the unit LCDs occupies a significant effective screen, and thus the continuity of the images between the unit LCDs is reduced. In addition, since the LCD is subjected to a high temperature process, a material that can withstand high temperatures is followed, and a large size is difficult due to a complicated manufacturing process.

Magnetic fluid display panels, like LCDs, are one of the non-active light emitting display devices. Magnetic fluid (ferromagnetic fluid) is a suspension in which ultra-fine ferromagnetic particles are stably dispersed in a liquid, as is generally known, and are not separated from ferromagnetic particles and liquid under normal centrifugal force or magnetic field. In a magnetic field it is a magnetic colloid that behaves as if it is magnetic. Such magnetic fluids include oxide magnetic fluids and metal magnetic fluids. An example of applying such a magnetic fluid is disclosed in European Patent 0633488 A1, in which the display panel applies a principle similar to that of a conventional LCD.

Specifically, as shown in FIG. 1, as shown in FIG. 1, a magnetic fluid 4 is interposed between the front plate 1 and the back plate 2, and a geometric anisotropy is provided at the rear side of the back plate 2 side. A plurality of magnetic field coils 3 in pixel units are provided for applying a magnetic field to a magnetic fluid 4 in which magnetic particles are dispersed, and the magnetic field coils 3 are connected to a display controller 5 for driving them. It is. The magnetic field coil 3 is provided by a structure in which a loop-shaped pattern formed in multiple layers on a multi-layered substrate is connected using a through hole. As shown in FIG. 2, the display panel applies a magnetic field to a portion ON where the light 6 is required to pass, so that the magnetic particles of the portion are aligned so that light can pass through, and the magnetic particles are not aligned. The light is absorbed and blocked in the part (OFF) which is naturally scattered without being scattered.

By the way, the magnetic particles of the magnetic fluid applied to the display panel of the conventional structure is extremely difficult to have geometric anisotropy in the ultrafine state, as well as the light control by the alignment / misalignment state of the magnetic particles is not desired. In addition, since the magnetic field coil 3 for providing a magnetic field to the magnetic fluid must be formed by a multi-layered structure, a process for manufacturing / processing the magnetic coil 3 is very difficult.

As another magnetic fluid display panel, U.S. Patent No. 3,863,249 does not use the alignment / unalignment of the magnetic fluid, but the magnetic fluid is present in the optical passage region by being placed in the optical passage region or moved elsewhere by the magnetic force. Depending on the presence and absence of light transmission is to be made. However, the magnetic fluid display panel here is unsuitable for realizing moving images because it requires a strong magnetic field that is structurally required for the movement of the magnetic fluid, and requires a large energy power, and the pixel switching responsiveness due to the magnetic fluid is very poor. Do. In addition, as the magnetic field forming means has a structure in which a magnetic coil made of a separate component is attached, it is difficult to miniaturize the cell, and the manufacturing cost is very high and the mass production is not suitable.

SUMMARY OF THE INVENTION An object of the present invention is to provide a display panel capable of realizing moving images by having fast response.

It is another object of the present invention to provide a magnetic fluid display panel which is low in cost and simple in structure and suitable for mass production.

In addition, an object of the present invention is to provide a magnetic fluid display panel that is advantageous in the construction of a large display device by multiple integration.

1 and 2 are schematic cross-sectional views of a conventional magnetic fluid display panel,

3 is a partial cross-sectional view of a first embodiment of a magnetic fluid display panel according to the present invention;

4A is an enlarged view of portion A of FIG. 3,

4B is an enlarged view of a portion B of FIG. 3,

FIG. 5 is an enlarged plan view of a pixel electrode applied to the first embodiment according to the present invention shown in FIG.

6 is a block diagram showing an electrode arrangement structure of a first embodiment according to the present invention,

7A and 7B are views illustrating a state in which a magnetic fluid is moved by driving a pixel electrode of a display panel of the present invention.

8 is a schematic cross-sectional view of a second embodiment according to the present invention in which a color filter layer is provided under a pixel electrode;

9 is a partial enlarged excerpt of FIG. 8;

FIG. 10 shows an arrangement structure of pixel electrodes of a second embodiment according to the present invention shown in FIG.

11 is a plan view showing an arrangement structure of pixel electrodes for a back plate of a third embodiment according to the present invention in which a color reflection layer is provided under the pixel electrodes;

12 is a cross-sectional view taken along the line AA ′ of FIG. 11;

13 is a cross-sectional view taken along the line B-B 'of FIG.

14 is a plan view showing the relative positional relationship between the first electrode and the second electrode of the third embodiment according to the present invention,

Fig. 15 is a schematic cross sectional view of a fourth embodiment according to the present invention in which a color filter is provided on the front plate side;

Fig. 16 is an excerpt sectional view of the front plate in the fifth embodiment according to the present invention in which a spacer is formed by a color filter;

17A to 17C are process diagrams illustrating a process of forming the color filter layer and the spacer layer of FIG. 16.

18 is a plan view of an excerpt of a pixel electrode of Embodiment 6 according to the present invention such that the pixel electrode includes two subpixel electrodes;

19A and 19B are schematic cross-sectional views of Embodiment 6 of FIG. 18 showing an operating state of a pixel;

20 is an excerpted plan view of a pixel electrode according to a seventh embodiment of the present invention in which a wall is formed along a boundary of a subpixel electrode or the like;

21 is an exploded perspective view showing the structure of the wall and the sub-pixel electrode of Example 7 according to the present invention,

22A and 22B are schematic cross-sectional views of Embodiment 7 of FIG. 20 showing an operating state of a pixel;

FIG. 23 is an exploded plan view of a pixel electrode of Embodiment 8 in which a wall is formed in the center of a dense area of subpixel electrodes;

24 is an exploded perspective view showing the structure of the wall and the subpixel electrode of Example 8 according to the present invention,

25A and 25B are schematic cross-sectional views of Embodiment 8 of FIG. 23 showing an operating state of a pixel;

Fig. 26 is a plan view showing an excerpt of a pixel electrode according to the ninth embodiment of the present invention in which the pixel electrodes form dense regions at predetermined intervals.

27A and 27B are schematic cross-sectional views of Embodiment 9 of FIG. 26 showing an operating state of a pixel;

Fig. 28 is an excerpt sectional view of the front plate of the tenth embodiment according to the present invention in which a spacer and a light shielding film are formed by a color filter;

29A to 29D are process diagrams illustrating a process of forming the color filter layer, the spacer, and the light shielding film of FIG. 28.

30 is a front view of a large display device incorporating a plurality of display panels of the present invention, and

31 to 42 are manufacturing process diagrams of one embodiment of a display panel according to the present invention.

In order to achieve the above object, the magnetic fluid display panel according to the present invention includes: a front plate and a back plate which maintain a constant gap; A plurality of first electrodes parallel to the inner surface of the back plate in a first direction on a stripe; Second electrodes arranged on the stripe in a direction orthogonal to the first electrodes while being electrically insulated from the first electrodes; It is provided at each intersection of the first electrode and the second electrode and has a light passing area through which light can pass, and is electrically connected to the adjacent first and second electrodes to form a magnetic field. A pixel electrode of a predetermined pattern; Magnetic fluid is formed on the inner surface of the back plate to a predetermined thickness; The feature is that it is provided.

In addition, the magnetic fluid display panel according to the present invention for achieving the above object: a front plate and a back plate to maintain a constant interval; A plurality of first electrodes parallel to the inner surface of the back plate in a first direction on a stripe; Second electrodes formed in a stripe shape on an inner surface of the back plate in a direction orthogonal to the first electrodes while being electrically insulated from the first electrodes; Third electrodes formed on the rear plate to be parallel to any one of the first electrode and the second electrode; The second subpixel electrode is formed in a predetermined pattern to form a magnetic field. The second subpixel electrode is formed in a predetermined pattern to form a compact region located between the first subpixel electrode and the compact region of the first pixel electrode. A pixel electrode, wherein the first subpixel electrode is electrically connected to the first electrode and the second electrode, and the second subpixel electrode is electrically connected to the second electrode and the third electrode; A magnetic fluid having a predetermined thickness on the back plate is in contact with the pixel electrode.

In addition, the manufacturing method of the display panel of the present invention to achieve the above object,

1) forming a plurality of first electrodes side by side in a first direction on a stripe on the inner surface of the back plate:

2) forming a first insulating film on the first electrode;

3) forming a second electrode on the first insulating film;

4) forming a second insulating film on the second electrode;

5) forming a pixel electrode having a light passing region in the generated magnetic field region by forming a magnetic field electrically connected to a first electrode and a second electrode on the second insulating film;

6) applying magnetic fluid to the pixel electrode and to the surface of the second insulating layer exposed to the light passing region with a predetermined thickness;

7) freezing the magnetic fluid;

8) polishing the magnetic fluid to a predetermined thickness to expose a surface of the pixel electrode;

And 9) fixing the front plate to the rear plate at a predetermined interval.

In addition, to achieve the above object another manufacturing method of the display panel according to the present invention,

1) forming a plurality of signal lines for transmitting a display signal on an outer surface of the back plate;

2) forming a first electrode on the inner surface of the back plate in a plurality of parallel directions in a first direction;

3) forming a first insulating film on the first electrode;

4) forming a second electrode on the first insulating film;

5) forming a second insulating film on the second electrode;

6) forming a through hole in the substrate, the through hole having a contact layer for electrically connecting the first electrode and the second electrode to a signal line formed on an outer surface of the rear plate;

7) forming a pixel electrode having a light passing region in the generated magnetic field region by forming a magnetic field electrically connected to a first electrode and a second electrode on the second insulating film;

8) applying magnetic fluid on the pixel electrode and on the surface of the second insulating layer exposed to the light passing region to a predetermined thickness;

9) freezing the magnetic fluid;

10) polishing the magnetic fluid to a predetermined thickness to expose a surface of the pixel electrode;

And 11) fixing the front plate to the rear plate at a predetermined interval.

Hereinafter, exemplary embodiments of the display panel of the present invention will be described in detail with reference to the accompanying drawings.

Example 1

3 is a partial cross-sectional view of the light transmissive display panel according to the present invention, FIG. 4A is an enlarged view of portion A of FIG. 3, and FIG. 4B is an enlarged view of portion B of FIG. 3. 5 is an enlarged plan view of the pixel electrode 24, and FIG. 6 is a configuration diagram illustrating an electrode arrangement structure of the display panel according to the present invention.

First, referring to FIG. 3, the front plate 10 and the back plate 20 of the transparent material are spaced apart at regular intervals. On the lowermost layer of the inner surface of the back plate 20, a plurality of first electrodes 21 are provided side by side in the first direction at predetermined intervals. On the first electrode 21, a plurality of second electrodes 22 are provided side by side in a direction orthogonal to the first direction with the first insulating layer 23a interposed therebetween. The second insulating layer 23b and the ferromagnetic shielding film 25 are provided on the second electrode 22. In this case, the second insulating layer 23b may be omitted when the ferromagnetic shielding layer 25 is insulative. If the ferromagnetic shielding layer 25 is not applied, the second insulating layer 23b may include the pixel electrode and the second electrode. Essential for electrical isolation between electrodes. The ferromagnetic shielding film 25 is provided with a pixel electrode 24 electrically connected to the first electrode 21 and the second electrode 22. At this time, both ends of the pixel electrode 24 are formed by the first and second contact layers 27a and 27b of the through holes 26a and 26b at the lower portion of the first electrode 21 and the second electrode 22. Electrically connected. That is, as shown in FIG. 4A, one end of the pixel electrode 24 is electrically connected to the second electrode 22 through the contact layer 27b of the through hole 26b at the bottom thereof, as shown in FIG. 4B. As described above, the other end of the pixel electrode 24 is electrically connected to the contact layer 27a of the through hole 26a below.

On the other hand, the pixel electrode 24 is formed in a zigzag shape as shown in FIG. 5 and is in contact with the first and second contact layers 27a and 27b as described above at both ends thereof.

The display panel according to the present invention having the structural features as described above has an X-Y matrix type electrode arrangement structure as a whole as shown in FIG. In the above structure, the pixel electrode 24 generates a magnetic field around by the current applied from the first electrode 21 and the second electrode 22, and the light passes through the light passing region 31 by the magnetic field. By attaching the magnetic fluid 30 blocking the body to the body to allow light to pass through the light passing area (31). That is, when a current is applied to the pixel electrode, the magnetic fluid is polarized by the magnetic field formed around the electrode. At this time, the intensity of the magnetic field becomes stronger as the pixel electrode 24 approaches the pixel electrode 24. The pressure in the body direction is applied, and thus the magnetic fluid 30 is attached to the pixel electrode 24. 7B shows a state in which the magnetic fluid 30 is located in the light passing region 31, that is, no current is applied to the pixel electrode 24, so that the surface tension of the magnetic fluid 30 and the adsorption force of the light passing region 31 are reduced. As a result, the state of staying in the light passing area 31 is prevented.

In addition, as shown in FIGS. 7A and 7B, the magnetic fluid 30 is separated from the front plate 10 and exists only on the rear plate 20 side. As described above, the pixel may be changed depending on whether the pixel electrode 24 is operated. The passage of light through the light passing region 31 is controlled while moving between the exposed surface of the light passing region 31 of the electrode 24 and the surface of the pixel electrode 24. In addition, as described above, when the magnetic fluid 30 is moved to the surface of the pixel electrode 24, the front plate 10 and the back plate 20 do not come into contact with the front plate 10. Spacing should be adjusted by a spacer provided between them. According to the experiment, the distance between the front plate 10 and the back plate 20 is 30 micrometers, and the height (thickness) of the pixel electrode 24 is 3 micrometers, and the line width is 3 micrometers, for example. It is preferable that the width of the meter and the light passing area 31 is 10 micrometers, and the thickness of the first electrode 21 and the second electrode 22 is preferably 1 micrometer. In order to minimize the distortion caused by the ferromagnetic shielding film was found to be preferable.

Example 2

8 shows a second embodiment according to the present invention in which a color filter layer 50 is provided below the pixel electrode 24. The overall structure in this second embodiment is substantially the same as that in the first embodiment shown in FIG. 9 is an enlarged view of a partial extract of FIG. 8.

10 shows an arrangement structure of pixel electrodes for color image realization, in which three unit pixel electrodes are gathered to form one unit set pixel electrode 24. That is, the unit collective pixel electrode 24 is composed of three unit pixel electrodes 24R, 24G, and 24B, and the unit collective color filter 50 also corresponds to the unit color filter 50R, 50G, 50B. Separated by. This is the same as in the general liquid crystal display device, and the concept of driving the unit pixel electrode of each pixel is the same as the color liquid crystal display device.

The light transmissive display panel has been described above. When the ferromagnetic shielding film or the color filter is provided with a function of reflecting light, a reflective display panel, which is the most preferable type of the display panel according to the present invention, can be obtained. In this way, circuit components for a display can be mounted on the rear surface of the rear panel, and in particular, through the through hole through the rear panel, electrical signals can be applied to the first electrode and the second electrode. It is possible to configure a large screen. For example, when the color filter in the above-described embodiment is replaced with a colored mirror, light of a specific wavelength is reflected among the light incident on the color filter, thereby realizing a color image even in the reflection type.

Example 3

FIG. 11 is a plan view showing an arrangement structure of pixel electrodes with respect to a back plate of a reflective display panel according to the present invention, FIG. 12 is a cross-sectional view taken along line aa 'of FIG. 11, and FIG. 14 is a plan view showing a relative positional relationship between the first electrode and the second electrode.

First, referring to FIG. 11, zigzag pixel electrodes 24 are arranged in a tiled arrangement. First and second contact layers 28a and 28b are disposed at both ends of each pixel electrode 24 for electrical connection between the first electrode 21 and the second electrode 22 positioned below the pixel electrode 24. In addition, first and second contact pillars 60 and 70 for electrical connection between the first and second electrodes 21 and 22 and the signal lines 61 and 71 to be described later are disposed below the pixel electrode 24. have.

12 and 13, the front plate 10 of the transparent material and the back plate 20 of the transparent or opaque material are spaced apart at regular intervals. The front plate 10 and the back plate 20 are formed on respective inner surfaces to maintain a predetermined distance by both spacer layers 11 and 12 in contact with each other. Here, the first spacer layer 12 of the back plate 20 is provided as the pixel electrode 24 to be described later, and the upper and lower spacer layers 11 and 12 are bonded to each other by adhesive or compression. A plurality of first electrodes 21 are arranged side by side in the first direction at predetermined intervals on the lowermost layer of the inner surface of the back plate 20. On the first electrode 21, a plurality of second electrodes 22 are provided side by side in a direction orthogonal to the first direction with the insulating layer 23a interposed therebetween. The ferromagnetic shielding film 25 made of an insulating material is provided on the second electrode 22. A colored color reflecting film 51 is formed on the ferromagnetic shielding film 25, and a pixel electrode 24 electrically connected to the first electrode 21 and the second electrode 22 is formed thereon. At this time, both ends of the pixel electrode 24 are electrically connected to the first electrode 21 and the second electrode 22 below by the contact layers 27a and 27b of the through holes 26a and 26b. . In addition to such a structure, the first electrode 21 and the second electrode 22 are formed on the back plate 20 through the contact layers 70 and 60 in the through holes 27 and 28 of the back plate 20. It is electrically connected with the 1st, 2nd signal lines 71 and 61 formed in the back surface. An electrical insulation layer 80 is interposed between the first signal line 71 and the second signal line 61.

Referring to FIG. 14, the first electrode 21 and the second electrode 22 are arranged orthogonally, and the second electrode 22 is divided into three unit electrodes 22R, 22G, and 22B for color screens. Are separated.

Small and large through holes 21a and 21b are formed in the first electrode 21 at predetermined intervals in the longitudinal direction in a set, and the through holes 21a are formed in the second electrodes 22R, 22G, and 22B. Through-holes 23a and 23b corresponding to 21b are formed. In the above through holes, the smaller ones are the parts where the corresponding contact layer is in contact, and the larger ones are expanded so as not to contact the contact layer.

Example 4

In the first to third embodiments, a means for implementing a color image, that is, a color filter layer and a color reflecting film is provided on the back plate side 20, but in this embodiment, a means for implementing a color image is provided on the front plate. It is provided inside (10). Referring to FIG. 15, color filters 50R, 50G, and 50B corresponding to each pixel electrode are formed on the inner surface of the front plate 10, and spacers 11 having a predetermined height are formed between the color filters 50. It is. An insulating film 23C is formed on the ferromagnetic shielding film 25. The insulating film 23C is replaced with the color reflecting film 51 in the structure of Fig. 12 described in the third embodiment. The insulating film 23C is used to insulate the lower electrical elements from each other, and the ferromagnetic shielding film and the lower electrical elements are appropriately designed to electrically insulate the lower electrical elements even by the ferromagnetic shielding film 25 located thereunder. Optional element that can be omitted if changed. And the second element has the same arrangement structure as in Example 3.

Example 5

In this embodiment, the structure of the fourth embodiment is improved, and the spacer layer 11a formed on the front plate 10 includes a red color filter 50R, a green color filter 50G, and a blue color filter 50B. ), And the elements on the back plate 20 side are the same as those of the fourth embodiment shown in FIG. Referring to Fig. 16, the spacer layer 11a is obtained by color filters 50R, 50G and 50B overlapping in the boundary region of each region R, G and B. At this time, since the color filters are R (red) G (green) B (blue), the pixel electrode 24 has a dark color in order to prevent the light passing through a region other than the spacer layer obtained by them from being reflected from the electrode. For example, it is preferable to make black.

17A to 17C are process diagrams illustrating a process of forming the color filter layer and the spacer.

As shown in FIG. 17A, first, a red filter layer 50R is formed in an R region and in an S region provided with a spacer layer.

As shown in Fig. 17B, the green filter layer 50G is formed in the G region and the S region.

As shown in Fig. 17C, blue filter layers 50B are formed in regions B and S.

The color filter layer may be formed by a general film forming process, for example, by the photolithographic method, and the spacer layer is formed without a separate thin film forming process.

Example 6

FIG. 18 illustrates an embodiment in which the electrical structures and the structure of the pixel electrode are improved, and thus, a faster recovery operation is possible by forcibly pushing and pulling a magnetic fluid. In FIG. 18, 28a is a first contact layer. 28b is a second contact layer, and 28c is a third contact layer. In the present embodiment, the unit pixel electrode includes two subpixel electrodes, and 24a is a first subpixel electrode connected to the first contact layer 28a and the second contact layer 28b. 24b connected to the contact layer 28b and the third contact layer 28c is a second subpixel electrode. In addition, three signal lines are required to drive the first subpixel electrode and the second subpixel electrode. In the above-described embodiment, any one of the first electrode and the second electrode, for example, A third electrode parallel to one electrode is required, for example, the first subpixel electrode is electrically connected to the first electrode and the second electrode, and the second electrode and the third electrode are connected to the second subpixel electrode ( 24b) can be connected. This configuration is omitted because it can be easily designed by a general technique in addition to the above-described embodiment.

In FIGS. 19A and 19B, 55 formed under the color filter 50 of the front plate 10 is a light shielding film formed to correspond to a dense portion of the second subpixel electrode 24b. Accordingly, a plurality of light shielding films 55 are formed per unit pixel. In the pixel electrode of FIG. 18, six light shielding films 55 are formed. In the pixel electrode having the above structure, when a current is applied to the first subpixel electrode 24a, a strong magnetic force is generated in this region, and magnetic fluid is concentrated on the second subpixel electrode 24b. When a current is applied to the two subpixel electrodes 24b, a strong magnetic force is generated in this region, and the magnetic fluid is concentrated on the first subpixel electrode 24a. As such, since the on and off states of the pixel are both made by the magnetic field, the operation speed is faster than the electric embodiments in which only one of the on and off states is made by the magnetic field. In addition, when metal is used as the pixel electrode, light can be reflected from the surface of the pixel electrode, thereby increasing the brightness of the image and easily using a thick magnetic fluid film.

As shown in FIG. 19A, when a current is applied to the first subpixel electrode 24a, a strong magnetic field is formed in the first subpixel electrode 24a, and thus a magnetic fluid ( The pressure in the vertical direction acts on the magnetic field 30 and pushes the magnetic fluid to the second subpixel electrode 24b to which no current is applied. Therefore, the thickness of the magnetic fluid adsorbed on the first subpixel electrode 24a is very low compared to the height of the magnetic fluid 30 positioned on the second subpixel electrode 25b. On the contrary, when a strong magnetic field is formed in the second subpixel electrode 24b as shown in FIG. 19B, a strong pressure in the vertical direction acts in the direction of the second subpixel electrode 24b so that no current is applied to the first subpixel electrode. It is pushed to (24a). Therefore, the thickness of the magnetic fluid adsorbed on the second subpixel electrode 24b is very low compared to the height of the magnetic fluid 30 positioned on the first subpixel electrode 24a.

According to the two states as described above, as shown in FIGS. 19A and 19B, a change in reflectance of light incident on the pixel occurs. As shown in FIGS. 19A and 19B, when the thickness of the magnetic fluid 30 formed in the first subpixel electrode 24 becomes thin, most of the light is reflected by the first subpixel electrode, resulting in a bright state of the pixel. . On the contrary, when the thickness of the magnetic fluid 30 formed on the first subpixel electrode 24a is thick, the reflection of light from the first subpixel electrode 24a is reduced, thereby maintaining a dark state. In this case, although the reflectance of the second subpixel electrode 24b in the off region is high, light does not reach the light shielding film 55, so that the entire pixel is always kept dark regardless of the operation of the pixel electrode. .

Example 7

In the seventh embodiment shown in FIG. 20, the wall 60 for supporting the magnetic fluid film is supported by a kind of capillary phenomenon in order to allow the magnetic fluid to be placed on the electrode in a thicker thickness than the sixth embodiment described above. The subpixel electrode 24a and the second subpixel electrode 24b have a structure that is continuously provided at a predetermined height along the boundary between the dense regions. As shown in FIG. 21, the wall blocks 60a are arranged at regular intervals along the boundary region as described above in a straight line so as to cause capillary phenomenon. 60 can be manufactured in a continuous form. By the way, it is advantageous that the wall is made of a hexahedral block as shown in FIG. 21 so as to obstruct the flow of the magnetic fluid 30 which is provided in the middle of the moving path of the magnetic fluid 30. Such a wall prevents the magnetic fluid 30 from flowing into one region.

Referring to FIG. 22A, a current is applied to the first subpixel electrode 24 so that the magnetic fluid 30 is adsorbed to a thin thickness by the same operation as in the sixth embodiment, and most of the magnetic fluid 30 The self pressure causes the second subpixel electrode 24b to collect in a dense area beyond the wall 60 or through the spaces between the walls 60.

On the contrary, when a current is applied to the second subpixel electrode 24b as shown in FIG. 22B, a portion of the magnetic fluid is strongly pressed in the dense region of the second subpixel electrode 24b by the same operation as described above. It moves to the dense area of the first subpixel electrode 24a.

Example 8

In the eighth embodiment of FIG. 23, the position of the wall in the seventh embodiment is changed, and the wall 60 is provided only outside the movement path of the magnetic fluid 30, and in particular, the structure is provided in the middle of the dense area of each electrode. That is, the wall 60 is provided in the middle of the dense region of the first subpixel electrode 24a and in the center of the second subpixel electrode 24a, as shown in FIG.

According to this structure, the wall 60 has a density of each pixel electrode rather than a function of holding and holding the magnetic fluid 30 moved from the dense area of one pixel electrode to the dense area of the other pixel electrode as in the seventh embodiment. It is provided in the center of the region to provide the adsorption force to help the magnetic fluid stays, as shown in Figure 25a the magnetic fluid 30 gathered in the region (OFF) of the second sub-pixel electrode 24b is not applied to the current ) In the middle by the adsorption force. In the region where the current is applied, the pressure due to the strong magnetic field at the corresponding pixel electrode is larger than the suction force of the wall 60, so that the magnetic fluid 30 is not included. can not do it. In FIG. 25B, when a current is applied to the second subpixel electrode 24b, the magnetic fluid 30 is collected on the first subpixel electrode 24a by the above-described action, and the magnetic fluid 30 is connected to the first subpixel. The state hold | maintained stably by the wall 60 in the electrode 24a is shown.

Example 9

FIG. 26 shows Embodiment 9 in which the second sub-pixel 24b is removed from the structure of Embodiments 6, 7, and 8, and a wall 60b having a predetermined area and height is provided in the vacant position.

Referring to FIG. 26, the pixel electrodes 24c connected to the first contact layer 28a and the second contact layer 28b have dense regions at equal intervals, and the wall 60b is formed between the dense regions. have.

As shown in FIG. 27A and FIG. 27B, the wall 60b is positioned below the light shielding film 55 having a predetermined width and height and located on the bottom of the front plate 10. In FIG. 27A, a current is applied to the pixel electrode 24c so that the magnetic fluid 30 is adsorbed to the pixel electrode 24c by a strong magnetic force, and the magnetic fluid 30 is formed by a magnetic field. By the action, it shows the state pushed up the said wall 60b. 27 shows a state in which current supply to the pixel electrode 24c is cut off and restored to the pixel electrode 24c by surface tension.

Example 10

The present embodiment is an improvement of the structure of Embodiment 5, wherein the spacer layer 11a and the light shielding film 55a formed on the front plate 10 have a red color filter 50R and a green color filter 50G. And it is obtained through the formation process of the blue color filter 50B. In this case, the light shielding film 55a is particularly applied in the case of a reflective type, and may be formed to correspond to the body of the pixel electrode, that is, in a portion away from the light passing region of the pixel electrode.

Referring to FIG. 28, the spacer 11b provided between the pixels and the light shielding film 55a provided in the pixels are provided in a portion where the color filters 51R, 51G, and 51B overlap.

29A to 29B are process diagrams illustrating a process of forming the color filter layer, the spacer, and the light shielding film.

As shown in FIG. 29A, the base layer 111 on which the spacer 11b is formed is formed on the inner surface of the substrate 10. The base layer 111 is provided in the boundary region between the pixels.

As shown in FIG. 29B, first, a red filter layer 50R is formed in the S region where the spacers are provided and the spacers where the light shielding is required.

As shown in Fig. 29C, a green filter layer 50G is formed in the G region and in the region where light shielding is required among the S region, the R region, and the G region.

As shown in FIG. 29D, the blue filter layer 50B is formed in the B region and the portion of the S region and the G region where light shielding is required to form a color filter, a spacer, and a light shield layer as shown in FIG. do.

This embodiment can be applied to any of the above-described embodiments in which the light shielding film is formed in the pixel region.

The formation of the color filter layer as described above may be performed by a general film forming process, for example, a photolithography method, and a separate thin film forming process for the spacer layer and the light shielding film will be described.

Hereinafter, a manufacturing process of the reflective display panel according to the present invention will be described with reference to FIGS. 31 to 42.

FIG. 31 shows a state in which the base plate is formed on the front and back surfaces by a general photolithography method or the like. That is, the first electrode 21, the insulating layer 23a, and the second electrode 22 are formed in a predetermined pattern on the front surface thereof, and the rear surface of the first electrode 21, the insulating layer 23a, and the second electrode 22 corresponds to the first electrode 21 and the second electrode 22. The first signal line 71 and the second signal line 61 are formed with the insulating layer 80 interposed therebetween.

The through hole 72 is formed in the first signal line 71, and the through hole 62 maintains a predetermined distance from the through hole 72 in the second signal line 61 and the insulating layer 80. Is formed. Through-holes 21a corresponding to the through-holes 72 of the first signal line 71 are formed in the first electrode 21, and the through-holes 21a of the second electrode 22 and the insulating layer 23a are formed in the first electrode 21. Through-holes 21a corresponding to the through-holes 62 of the second signal line 61 and through-holes 21c for electrical contact between the pixel electrodes to be described later are formed at a predetermined distance from the through-holes 21a.

Referring to FIG. 32, an insulating ferromagnetic shielding film 25 is formed on the second electrode 22 in addition to the structure shown in FIG. 31. The ferromagnetic shielding film 25 is concentric with the through-hole 21a of the second electrode 22 and concentric with the through-hole 25a having a smaller diameter and the through-hole 21a of the first electrode 21. In this case, a through hole 25b having a smaller diameter is formed.

Referring to FIG. 33, masks 81 and 82 for plating are formed on both sides of the structure. At this time, the first mask 81 on the upper side is formed concentrically with the through holes 25a and 25b of the ferromagnetic shielding film 25, and through holes 81a and 81b having a larger diameter are formed. Further, through holes 82a and 82b corresponding to the through holes 23a and 21b of the first electrode 21 and the second electrode 22 are formed in the second mask 82 on the lower side. At this time, the through hole 82a has a smaller diameter than the through hole 62 of the second signal line 61, and the through hole 82b is smaller than the through hole 72 of the first signal line 71.

Referring to FIG. 34, through holes 27 and 28 are formed in the substrate. At this time, the through holes 27 and 28 are located at the center portions of the through holes corresponding to the first and second masks 81 and 82, respectively.

As shown in FIG. 35, plating is performed to form the positive contact layers 70 and 60 in the through holes 27 and 28, and the first electrode is formed by the positive contact layers 70 and 60. Reference numeral 21 and the first signal line 71 and the second electrode 22 and the second signal line 61 are electrically connected to each other.

As shown in Fig. 36, the first and second masks are removed by a lift-off method so that the contact layers 60 and 70 formed by plating are electrically separated from each other, and a polishing method is necessary. The entire exposed surface is polished to increase the smoothness of the surface.

As shown in FIG. 37, a color reflective film 50 is formed on the ferromagnetic shielding film 25. At this time, the color reflection film 50 has a through hole corresponding to the through hole H for electrical contact between the pixel electrode and the first electrode 21 which will be described later.

As shown in FIG. 38, a first spacer 12 between the pixel electrode 24 and the pixel electrodes is formed on the color reflecting film 50. At this time, the pixel electrode 24 is electrically connected to the first and second electrodes thereunder by the contact layers 27a and 27b.

As shown in FIG. 39, the magnetic fluid 30 is formed on the pixel electrode 24 by a spin coating method to a predetermined thickness, and the magnetic fluid 30 is frozen.

As shown in FIG. 40, the surface of the frozen magnetic fluid 30 is polished to a predetermined depth to expose the pixel electrode 24.

As shown in FIG. 41, the front plate 10 having the second spacer corresponding to the first spacer 12 on the inner surface of the predetermined height is bonded to the back plate 20, and the inner surface shown in FIG. Obtain a completed display panel as shown. At this time, the bonding is made between the first and second spacers, and the adhesive force at this time is maintained by mutual compression or adhesive.

The display panel of the present invention described above does not require a liquid crystal injection process as in a liquid crystal display device, and only applies a magnetic fluid to the inner surface of the rear plate and then spaces the distance so that the magnetic fluid does not touch the front plate. To the back plate. Therefore, air is present in the space in which the magnetic fluid is present, and at the edge thereof, barrier ribs requiring extremely airtight, as in the liquid crystal display device, are not required.

In addition, in the aforementioned reflective display panel, since an electrical signal to the first electrode 21 and the second electrode 22 is applied from the rear surface of the back plate through the contact layers 70 and 60, the reflective display panel is different from that of a general display panel. Likewise, the terminal portion of the edge for applying the signal to the first electrode and the second electrode is unnecessary, so that the entire panel can be used as the screen and the margin of the edge can be minimized. Therefore, as shown in FIG. 30, when a large number of display panels 100 of the present invention are integrated to form a large display apparatus 1000, the boundary between the unit display panels 100 is minimized by the margin as described above. Since the width of the 110 can be minimized, a large number can be integrated such that the distance between adjacent pixels between the unit display panels can be maintained at the same distance as that of the pixels of the same panel. .

In addition, by providing a plurality of contact layers connecting the signal lines and the first and second electrodes at predetermined intervals for each electrode, voltage drop per region of each electrode may be suppressed. In other words, the signal is applied to one end or both ends of each electrode in the related art, but in the present invention, the voltage drop in the electrode having a high resistance can be significantly reduced by providing a plurality in the middle portion of each electrode.

The embodiments of the magnetic fluid display panel of the present invention described above do not limit the scope of the present invention, and a person skilled in the art of the display device may change the design in various forms based on the above embodiments. It is also obvious that it is also within the scope of the present invention.

Claims (35)

A front panel and a back panel that maintain a constant gap; A plurality of first electrodes parallel to the inner surface of the back plate in a first direction on a stripe; Second electrodes arranged on the stripe in a direction orthogonal to the first electrodes while being electrically insulated from the first electrodes; It is provided at each intersection of the first electrode and the second electrode and has a light passing area through which light can pass, and is electrically connected to the adjacent first and second electrodes to generate a magnetic field in a planar direction. A pixel electrode of a predetermined pattern which can be formed; And a magnetic fluid present on the inner surface of the back plate to be in contact with the pixel electrode. The method of claim 1, And a color filter disposed under the pixel electrode. The method of claim 1, And a ferromagnetic shielding film formed under the pixel electrode. The method of claim 1, And the pixel electrode is zigzag-shaped. The method of claim 1, A magnetic fluid display panel, characterized in that a color reflection film is provided on the lower layer of the pixel electrode. The method of claim 1, And a color filter corresponding to the pixel electrode on the front panel. The magnetic filter of claim 6, wherein the color filter includes a unit color filter having a plurality of colors, and a spacer formed by overlapping the unit color filters is provided at a predetermined width portion of a boundary area of the unit color filters. Fluid display panel. The method according to claim 6 or 7, And the pixel electrode is zigzag-shaped. The method according to claim 4 or 7, A plurality of signal lines are disposed on the rear surface of the rear plate for signal transmission to the first electrode and the second electrode, and the rear plate contacts for electrically contacting the first electrode and the second electrode with the signal line. Magnetic fluid display panel, characterized in that the through-hole provided with a layer is formed. The method according to any one of claims 1 to 6, And a spacer layer for maintaining a gap between the front plate and the back plate. The method of claim 10, The spacer comprises a first spacer provided on the inner surface of the back plate and a second spacer provided on the inner surface of the front plate. The method of claim 11, And the first spacer is manufactured in the same step as the pixel electrode. The method according to any one of claims 1 to 8, The magnetic fluid display panel of the magnetic fluid is located only on the inner surface of the back plate. The method of claim 1, The pixel electrode is formed in a zigzag form such that a plurality of dense regions are provided at predetermined intervals, and a magnetic body display panel is formed between walls having a predetermined width and height. The method of claim 14, And a light shielding film corresponding to the wall on the inner surface of the front plate. The method of claim 6, The color filter includes a unit color filter having a plurality of colors, a spacer formed by overlapping the unit color filters in a boundary region between the unit color filters, and a light shielding film in a region outside the light passing region of each pixel electrode. A magnetic fluid display panel, characterized in that is formed. The magnetic fluid display panel of claim 16, wherein the light shielding layer is formed by overlapping the unit color filters. A front panel and a back panel that maintain a constant gap; A plurality of first electrodes parallel to the inner surface of the back plate in a first direction on a stripe; Second electrodes formed in a stripe shape on the back plate in a direction orthogonal to the first electrodes while being electrically insulated from the first electrodes; Third electrodes formed on the rear plate to be parallel to any one of the first electrode and the second electrode; The first part includes a first subpixel electrode having a dense area of a predetermined interval and a second subpixel electrode of a predetermined pattern having a dense area of the first subpixel electrode, which are formed in a predetermined pattern to form a magnetic field. A pixel electrode having a door such that the pixel electrode is electrically connected to the first electrode and the second electrode and the second subpixel electrode is electrically connected to the second electrode and the third electrode; And a magnetic fluid having a predetermined thickness to contact the pixel electrode on the back plate. The method of claim 18, And a ferromagnetic shielding film formed under the pixel electrode. The method of claim 18, And the pixel electrode is zigzag-shaped. The method of claim 18, And a color filter corresponding to the pixel electrode on the front panel. The method of claim 18, And a color reflecting film provided on the lower layer of the pixel electrode. The method according to any one of claims 18 to 22, Display panel, characterized in that the spacer for maintaining the gap between the front plate and the back plate. The method of claim 23, wherein The spacer includes a first spacer provided on an inner surface of the rear plate and a second spacer provided on an inner surface of the front plate. The method of claim 24, The first spacer is manufactured in the same step as the pixel electrode. The method of claim 21, The color filter includes a unit color filter having a plurality of colors, and the magnetic fluid display panel is configured to form the spacer by overlapping the unit color filter in a predetermined width portion of a boundary area of the unit color filters. . The method of claim 18, And a wall having a predetermined width and height along a boundary between the first subpixel electrode and the second subpixel electrode. The method of claim 18, And a light shielding film corresponding to the wall on the inner surface of the front plate. The method of claim 21, The color filter includes a unit color filter having a plurality of colors, a spacer formed by overlapping the unit color filters in a boundary region between the unit color filters, and a light shielding film in a region outside the light passing region of each pixel electrode. A magnetic fluid display panel, characterized in that is formed. 29. The magnetic fluid display panel of claim 28, wherein the light shielding layer is formed by overlapping the unit color filters. The method of claim 18, And a wall having a predetermined width and height formed between the dense region of the first subpixel electrode and the dense region of the second subpixel electrode. The method of claim 18, And a wall having a predetermined width and height formed at each central portion of the dense area of the first subpixel electrode and the dense area of the second subpixel electrode. 33. The method of claim 31 or 32, The wall is a magnetic fluid display panel, characterized in that the unit blocks having a predetermined width and height are arranged at a predetermined interval. 1) forming a first electrode on the inner surface of the back plate in a plurality of parallel directions in a first direction; 2) forming a first insulating film on the first electrode; 3) forming a second electrode on the first insulating film; 4) forming a second insulating film on the second electrode; 5) forming a pixel electrode having a light passing region in the generated magnetic field region by forming a magnetic field electrically connected to a first electrode and a second electrode on the second insulating film; 6) applying a predetermined thickness roll of magnetic fluid on the pixel electrode and the surface of the second insulating layer exposed to the light passing region; 7) freezing the magnetic fluid; 8) polishing the magnetic fluid to a predetermined thickness to expose a surface of the pixel electrode; 9) fixing the front plate to the rear plate at a predetermined interval; manufacturing method of a display panel comprising a. 1) forming a plurality of signal lines for transmitting a display signal on the outer surface of the back plate; 2) forming a first electrode on the inner surface of the back plate in a plurality of parallel directions in a first direction; 3) forming a first insulating film on the first electrode; 4) forming a second electrode on the first insulating angle; 5) forming a second insulating film on the second electrode; 6) forming a through hole in the substrate, the through hole having a contact layer for electrically connecting the first electrode and the second electrode to a signal line formed on an outer surface of the rear plate; 7) forming a pixel electrode on the second insulating layer, the pixel electrode having a light passing region formed in the magnetic field region by forming a magnetic field electrically connected to a first electrode and a second electrode; 8) applying magnetic fluid on the pixel electrode and on the surface of the second insulating layer exposed to the light passing region to a predetermined thickness; 9) freezing the magnetic fluid; 10) polishing the magnetic fluid to a predetermined thickness to expose a surface of the pixel electrode; 11) fixing the front plate to the rear plate at a predetermined interval; manufacturing method of a display panel comprising a.

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