KR100615191B1 - Plasma display panel comprising micro-lens array - Google Patents

Abstract

An object of the present invention is to provide a plasma display panel having excellent brightness and luminous efficiency. To achieve this object, a first microlens array having a plurality of microlenses, and disposed on a rear surface of the first microlens array The front substrate, a plurality of sustain electrode pairs formed on the rear surface of the front substrate, bus electrodes formed on the back of the sustain electrode pairs, the sustain electrode pairs, and the bus electrodes to be embedded. A front dielectric layer formed on a rear surface of the second dielectric layer disposed on a rear surface of the front dielectric layer, corresponding to the first microlens array, and having a plurality of microlenses, and spaced apart from the front substrate by a predetermined distance; And a back substrate coupled to face each other to form a discharge space, and the sustain electrode pair A plurality of address electrodes formed on the front surface of the back substrate so as to intersect, a back dielectric layer formed on the front surface of the back substrate so that the address electrodes are embedded, a partition wall formed on the front surface of the back dielectric layer, and partitioning a discharge cell; And a phosphor coated in the discharge cell.

Description

 Plasma display panel comprising microlens array {Plasma display panel comprising micro-lens array}

1 is a view showing the path of visible light incident on a typical plasma display panel top plate,

2 is a cross-sectional view of a plasma display panel according to an embodiment of the present invention;

3 is a perspective view of an upper plate of the plasma display panel of FIG. 2;

4 is a view illustrating a path of visible light incident on the upper panel of the plasma display panel of FIG. 2;

5A is a schematic perspective view of a rectangular microlens array,

5B is a schematic perspective view of a hexagonal microlens array.

Explanation of symbols on the main parts of the drawings

100: plasma display panel 111: front substrate

112: sustain electrode pair 114: bus electrode

115: front dielectric layer 116: protective layer

121: back substrate 122: address electrode

125 back dielectric layer 126 phosphor layer

130: partition 140: external light reflection absorbing layer

150: upper plate 160: lower plate

170: visible light 180: second micro lens

183: second microlens array 185: first microlens

187: first microlens array 190: discharge cell

195: optical axis

The present invention relates to a plasma display panel, and more particularly, to a plasma display panel having improved luminance by using a micro lens.

Recently, a plasma display panel, which is drawing attention as a replacement of a conventional cathode ray tube display device, is discharged after a discharge gas is filled between two substrates on which a plurality of electrodes are formed. The phosphor formed in a predetermined pattern by the ultraviolet rays is excited to obtain a desired image.

The plasma display panel may be classified into a direct current type and an alternating current type according to a discharge type. In the DC plasma display panel, the electrodes are exposed to the discharge space so that the movement of charged particles is directly performed between the corresponding electrodes. In the AC plasma display panel, at least one electrode is covered with a dielectric layer, so that the direct charges of the corresponding electrodes are mutually reduced. The discharge is performed by the electric field of the wall charge instead of the movement of.

1 illustrates a top plate 50 of a typical plasma display panel. As shown, the sustain electrode pair 12 in which the X electrode 31 and the Y electrode 32 are paired is formed on the rear surface of the front substrate 11. Bus electrodes 14 are formed on the rear surface of the sustain electrode pair 12. In addition, the front dielectric layer 15 is formed on the rear surface of the front substrate 11 so that the sustain electrode pairs 12 and the bus electrodes 12 are embedded. In the non-discharge portion between the sustain electrode pairs 12, an external light reflection absorbing layer 40 formed in parallel with the sustain electrode pair 12 is disposed, and a protective layer 16 is provided on the rear surface of the front dielectric layer 15. The MgO layer is formed.

The sustain electrode pair 12 is generally formed of a transparent electrode in order to increase the luminance of visible light generated in the discharge space. However, since the bus electrode 14 requires high electrical conductivity, the bus electrode 14 is generally formed of a metal, and the external light reflection absorbing layer 40 is formed of a black material to prevent external light reflection. Therefore, it is difficult for visible light generated in the discharge space to pass through the bus electrode 14 and the external light reflection absorbing layer 40. Referring to FIG. 1, it can be seen that visible light A directed to the external light reflection absorbing layer 40 and visible light B directed to the bus electrode 14 do not pass through them. That is, the visible light C incident on the sustain electrode 12 in which the bus electrode 14 is not formed, or the visible light D incident between the pair of sustain electrodes 12 forms the front substrate 11. Pass through and out. Therefore, the brightness and efficiency of the plasma display panel are reduced by the bus electrode 14 and the external light reflection absorbing layer 40.

In order to solve the above problems, an object of the present invention is to provide a plasma display panel having a micro-lens array.

In order to achieve the above and other objects, the present invention provides a first microlens array having a plurality of microlenses, a front substrate disposed on a rear surface of the first microlens array, and a rear surface of the front substrate. A plurality of sustain electrode pairs formed, a bus electrode formed on a bottom of the sustain electrode pairs, a front dielectric layer formed on a rear surface of the front substrate so that the sustain electrode pairs and the bus electrodes are embedded, the front surface A second microlens array disposed on a rear surface of the dielectric layer, corresponding to the first microlens array, and having a plurality of microlenses, and spaced apart from each other by a predetermined distance to face the front substrate to form a discharge space; A plurality of substrates formed on the front surface of the rear substrate so as to intersect the substrate and the sustain electrode pair; And an address electrode, a back dielectric layer formed on the front surface of the back substrate so that the address electrodes are embedded, a partition wall formed on the front surface of the back dielectric layer and partitioning a discharge cell, and a phosphor coated in the discharge cell. A plasma display panel is provided.

In the present invention, preferably, in the plasma display panel, the first microlens array and the second microlens array may form a telecentric system.

In the present invention, preferably, in the plasma display panel, the one first microlens and one second microlense corresponding to the one first microlens may be arranged in pairs for each of the discharge cells. .

In this case, preferably, the one first microlens and the one second microlense corresponding to the one first microlens may have the same optical axis.

Next, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

2 to 5, a plasma display panel 100 according to an exemplary embodiment of the present invention is shown. 2 is a cross-sectional view of the plasma display panel 100, FIG. 3 is a perspective view of the plasma display panel top plate 150, and FIG. to be. 5 shows various shapes of the microlens array.

As shown, the AC plasma display panel 100 according to the present invention includes an upper plate 150 showing an image to a user and a lower plate 160 coupled in parallel thereto. 2 shows a state in which the lower plate 160 is rotated 90 degrees for convenience of description. On the front substrate 111 of the upper plate 150, a sustain electrode pair 112 is formed in which the X electrode 131 and the Y electrode 132 are paired, and the sustain electrode pair 112 of the front substrate 111 is disposed. The address electrode 122 is disposed on the rear substrate 121 of the lower plate 160 opposite to the disposed surface such that the address electrodes 122 intersect with the electrodes 131 and 132 of the front substrate 111. The sustain electrode pair 112 including the X and Y electrodes 131 and 132 of the front substrate 111 may preferably use a transparent electrode made of indium tin oxide (ITO). On the back of these transparent electrodes, a bus electrode 114 having a narrow width is disposed to reduce line resistance. The bus electrode 114 is generally formed of a metal having excellent electrical conductivity. The space formed by the pair of X and Y electrodes 131 and 132 and the address electrodes 122 intersecting with each other forms one discharge unit as the unit discharge cell 190. In order to increase contrast, an external light reflection absorbing layer 140 formed in parallel with the sustain electrode pair 112 is disposed in the non-discharge portion between the sustain electrode pairs 112.

The front dielectric layer 115 and the front substrate 111 having the X and Y electrodes 131 and 132 and the back substrate 121 having the address electrode 122 are buried therein, respectively. The back dielectric layer 125 is formed. A barrier rib 130 is formed on the front surface of the back dielectric layer 125 to maintain a discharge distance and to prevent electro-optic crosstalk between the discharge cells 190. Red, green, and blue phosphors 126 are coated on both side surfaces of the barrier rib 130 and the rear dielectric layer 125 on which the barrier rib 130 is not formed.

The first microlens array 187 is disposed on the front surface of the front substrate 111. The first microlens array 187 may be formed in an array of a plurality of microlenses 185 and may have a rectangular array or a hexagonal array in consideration of the type of the plasma display panel. 5A shows a square microlens array and FIG. 5B shows a hexagonal microarray.

The first microlens array 187 corresponds to the second microlens array 183 disposed on the rear surface of the front dielectric layer 115. Therefore, when the first microlens array 187 is a rectangular array, the second microlens array 183 also has a rectangular array. On the other hand, when the first microlens array 187 is a hexagonal array, the second microlens array 183 also has a hexagonal array. An MgO layer is formed on the back surface of the second microlens array 183 as the protective layer 116.

The first and second microlens arrays 187 and 183 include a plurality of first microlenses 185 and second microlenses 180, respectively. The first microlens array 187 may be arranged using a plurality of discharge cells 190 as one unit, but it is preferable to form each of the discharge cells 190 as a base unit as shown in FIG. 3. . Accordingly, in the case of the plasma display panel having a rectangular or hexagonal matrix shape, the first and second microlens arrays 187 and 183 may have a rectangular or hexagonal matrix shape, respectively. In the case of the plasma display panel 100 according to an exemplary embodiment of the present invention, since the plasma display panel 100 has a rectangular matrix shape, the first and second microlens arrays 187 and 183 have a rectangular array shape.

Each first microlens 185 is paired with one corresponding second microlens 180. The paired first and second microlenses 185 and 180 are optically telecentric, and share the same optical axis 170. Telecentric systems are optical systems that do not produce magnification errors even when focusing is incomplete. Therefore, when visible rays generated at various positions in the discharge cell 190, such as the plasma display panel 100, are visually recognized by an external user through the first and second microlenses 185 and 180, The image according to each discharge cell 190 can be clearly seen.

Referring to FIG. 4, the path of the visible light 170 generated in the discharge cells 190 of the plasma display panel 100 is illustrated. In general, the visible light 170 generated in the discharge cell 190 has various paths, but the amount of incident light in the substantially vertical direction of the front substrate 111 is the highest. Therefore, for convenience of description, the visible light 170 incident in the vertical direction of the front substrate 111 is representatively shown in FIG. 4. As described above, the visible light 170 is hardly transmitted to the portion of the front substrate 111 in which the bus electrode 114 or the external light reflection absorbing layer 140 is formed. Therefore, in the plasma display panel 100 according to the present invention, most of the visible light 170 incident from the discharge cell 190 is refracted by the second microlens 180 to pass the visible light. Incident on (111). That is, the visible light 187 refracted by the second microlens 180 is between the sustain electrode pair 112 or the pair of sustain electrodes 131 and 132 where the bus electrode 114 is not formed. It is incident to the part of. Thereafter, the visible light 170 passes through the front substrate 111 and is refracted by the first micro lens 185 to be emitted to the outside.

In the plasma display panel 100 according to an embodiment of the present invention, since the first and second microlenses 185 and 180 have the same optical axis 195 and form a telecentric system, the plasma display panel 100 The user of 100 may clearly see the image generated by the visible light 170 generated in the discharge cells 190. In particular, in the embodiment according to the present invention, since the first and second microlenses 187 and 187 are arranged in pairs for each discharge cell 190, the bus electrode 114 or the external light reflection absorbing layer 140 is disposed. In which the visible light 187 is suppressed from being lost by reflection or absorption. Therefore, the luminance of the plasma display panel 100 is increased, and the luminous efficiency is improved.

The operation of the plasma display panel 100 having such a structure is as follows. When a predetermined voltage is applied to the address electrode 122 and the Y electrode 132, an address discharge occurs between the two electrodes, and wall charges are charged on the front dielectric layer 115 to select the discharge cell 190 for light emission. do. When a predetermined voltage is applied between the X electrode 131 and the Y electrode 132, wall charges move between the two electrodes 131 and 132, causing the discharge gas to generate a sustain discharge, thereby discharging the discharge gas. Generates ultraviolet rays, and the generated ultraviolet rays excite the phosphor 126 to form an image. In this case, the plasma display panel 100 implements a gray level required for displaying an image by adjusting the number of sustain discharges according to the video data, and in order to express such a gray level, one frame usually has a different number of discharge times. The ADS (Address and Display Period Separated) method of driving by dividing into several subfields is mainly used.

Like reference numerals in the drawings shown above indicate the same members.

The plasma display panel according to the present invention has the following effects.

First, the visible light generated in each discharge cell in the bus electrode or the external light reflection absorbing layer is suppressed by reflection or absorption by the first and second microlens arrays. Therefore, the luminance of the plasma display panel is increased, and the luminous efficiency is improved. In particular, when paired first and second microlenses are arranged in units of discharge cells of the plasma display panel, luminance and luminous efficiency are greatly improved.

Second, when the first and second microlens arrays form an optically telecentric system, the user can clearly see the image generated in each discharge cell.

Although the present invention has been described with reference to the embodiments shown in the drawings, this is merely exemplary, and it will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

Claims (4)

A first micro-lens array having a plurality of microlenses; A front substrate disposed on a rear surface of the first microlens array; A plurality of sustain electrode pairs formed on the rear surface of the front substrate; Bus electrodes formed on rear surfaces of the sustain electrode pairs; A front dielectric layer formed on a rear surface of the front substrate so that the sustain electrode pairs and the bus electrodes are embedded; A second microlens array disposed on a rear surface of the front dielectric layer and corresponding to the first microlens array and having a plurality of microlenses; A rear substrate which is spaced apart from the front substrate by a predetermined interval and coupled to face the front substrate to form a discharge space; A plurality of address electrodes formed on the front surface of the rear substrate so as to cross the sustain electrode pairs; A back dielectric layer formed on the front surface of the back substrate to embed the address electrodes; Barrier ribs formed on an entire surface of the rear dielectric layer to partition discharge cells; And And a phosphor coated in the discharge cell. And the first microlens array and the second microlens array form a telecentric system. delete The plasma display panel of claim 1, wherein the one first microlens and one second microlense corresponding to the first microlens are arranged in pairs for each of the discharge cells. 4. The plasma display panel of claim 3, wherein the one first microlens and one second microlense corresponding to the first microlens have the same optical axis.

Images