KR100433221B1 - Fluorescent material of plasma display panel - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a phosphor of a plasma display panel which is intended to prolong life and to lower discharge voltage.

The phosphor of the plasma display panel according to the embodiment of the present invention is (Ba, Mg, Zn) ₃ SiO ₇ : Pb ²⁺ , (Ca, Zn) ₃ (PO ₄ ) ₂ which is excited by energy of a wavelength different from vacuum ultraviolet rays. : Tl ^+, MgO: Gd ^3+, and Y ₂ O _3: Gd ³⁺ is a characterized in that any one of an ultraviolet fluorescent material mixed in.

Description

Phosphor of plasma display panel {FLUORESCENT MATERIAL OF PLASMA DISPLAY PANEL}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma display panel, and more particularly, to a phosphor of a plasma display panel, which extends its life and lowers a discharge voltage.

Plasma Display Panel (hereinafter referred to as "PDP") is an image of 147 nm vacuum ultraviolet rays generated when an inert mixed gas such as He + Xe, Ne + Xe, He + Xe + Ne discharges to emit phosphors. Will be displayed. Such PDPs are not only thin and large in size, but also have improved in image quality due to recent technology development.

Referring to FIG. 1, a discharge cell of a three-electrode AC surface discharge type PDP includes a sustain electrode pair 4 formed on the upper substrate 16 and an address electrode 2 formed on the lower substrate 14. .

Each of the sustain electrode pairs 4 includes a transparent electrode such as indium tin oxide (ITO), and a metal bus electrode having a line width smaller than that of the transparent electrode and formed at one edge of the transparent electrode. The upper dielectric layer 12 and the passivation layer 10 are stacked on the upper substrate 16 on which the sustain electrode pairs 4 are formed. Wall charges generated during plasma discharge are accumulated in the upper dielectric layer 12. The passivation layer 10 prevents damage to the upper dielectric layer 12 and the sustain electrode pair 4 due to sputtering generated during plasma discharge, and increases emission efficiency of secondary electrons. As the protective film 10, magnesium oxide (MgO) is usually used.

The lower dielectric layer 18 and the partition wall 8 are formed on the lower substrate 14 on which the address electrode 2 is formed, and the phosphor 6 is formed on the surfaces of the lower dielectric layer 18 and the partition wall 8. The address electrode 2 is orthogonal to the sustain electrode pair 4. The partition 8 is formed in parallel with the address electrode 2 to prevent the ultraviolet rays and the visible light generated by the discharge from leaking to the adjacent discharge cells. The phosphor 6 is excited by vacuum ultraviolet (VUV) generated during plasma discharge to generate visible light of any one of red, green, and blue.

An inert mixed gas such as He + Xe, Ne + Xe, He + Xe + Ne for discharging is injected into the discharge space of the discharge cells provided between the upper and lower substrates 16 and 14 and the partition wall 8.

The phosphor 6 is made of an ultraviolet-excited fluorescent material that is excited by vacuum ultraviolet (VUV) light, and is divided into a red phosphor, a green phosphor, and a blue phosphor according to the wavelength of light emitted.

Referring to FIG. 2, a red phosphor generally used in PDP is (YGd) BO ₃ : Eu ³⁺ , and a green phosphor is Zn ₂ SiO ₄ : Mn ²⁺ . The composition of the blue phosphor is BaMgAl ₁₀ O ₁₇ : Eu ²⁺ . However, the green phosphor has a negative charging characteristic, unlike the red and blue phosphors whose charging characteristics are positive. In addition, the green phosphor has a lower dielectric constant than the red and blue phosphors. Due to such a difference in charging characteristics and permittivity, the green phosphor easily breaks crystals due to the collision of a cation with a larger mass than the anion, and thus has a shorter lifespan than the red and blue phosphors. In addition, the red, green, and blue phosphors used in the conventional PDP have a light absorption rate of 147 nm vacuum ultraviolet (VUV) excitation source, which is Xe resonance, smaller than that of 200-400 nm ultraviolet (UV) excitation source. Therefore, the luminous efficiency is lowered when excited only by vacuum ultraviolet (VUV), and most of the excitation energy is consumed as thermal energy, resulting in low lifespan. In addition, electrons generated from the electrode to which the negative scan voltage is applied in the sustain electrode pair 4 during the address discharge for selecting the cell should be moved toward the address electrode 2 to which the bipolar data voltage is applied. Due to the electrostatic repulsion caused by the '-' charging characteristic of the electrons, free movement of the electrons toward the address electrode 2 is inhibited. As a result, a significant magnitude of voltage drop occurs during address discharge, delayed discharge, and the voltage required for discharge increase accordingly, thereby increasing power consumption. As a result, an address is increased during high-speed driving due to an increase in resolution of a panel and addition of a subfield. Miss (Address miss) may occur.

Accordingly, it is an object of the present invention to provide a phosphor of a PDP that extends the life and lowers the discharge voltage.

1 is a perspective view showing a discharge cell structure of a conventional three-electrode AC surface discharge type plasma display panel.

FIG. 2 is a cross-sectional view of a portion of the plasma display panel shown in FIG. 1.

3 is a cross-sectional view illustrating a plasma display panel according to an exemplary embodiment of the present invention.

4 is a diagram schematically illustrating a light emitting mechanism of a phosphor applied to a plasma display panel according to an exemplary embodiment of the present invention.

<Description of Symbols for Main Parts of Drawings>

2,32: address electrode 4,34: sustain electrode pair

6,36R, 36G, 36B: Phosphor 8,38: Bulkhead

10,40: protective film 12,18,42,48: dielectric layer

14,44: Lower board 16,46: Upper board

In order to achieve the above object, the phosphor of the PDP according to the embodiment of the present invention is (Ba, Mg, Zn) ₃ SiO ₇ : Pb ²⁺ , (Ca, Zn) ₃ which is excited by energy of a wavelength different from vacuum ultraviolet rays (PO _{4) 2:} is the Gd ³⁺ characterized in that any one of an ultraviolet fluorescent substance mixed ^{in: Tl +, MgO: Gd 3+} , Y 2 O 3.

The phosphor of the PDP according to the embodiment of the present invention further includes a vacuum ultraviolet phosphor in which the ultraviolet phosphor material is mixed and excited by vacuum ultraviolet rays.

The ultraviolet phosphor material is characterized in that the charging characteristics are positive.

The ultraviolet phosphor material is characterized by being excited by energy of a wavelength of 200 to 400nm.

The light emitting center of the ultraviolet phosphor material may be at least one of Gd ³⁺ , Ce ³⁺ and Eu ²⁺ .

The ultraviolet phosphor material is characterized in that it is mixed with the vacuum ultraviolet phosphor at 1 to 99% by weight compared to the vacuum ultraviolet phosphor.

The vacuum ultraviolet phosphor is at least one of (YGd) BO ₃ : Eu ³⁺ , Zn ₂ SiO ₄ : Mn ²⁺ and BaMgAl ₁₀ O ₁₇ : Eu ²⁺ .

Hereinafter, exemplary embodiments of the present invention will be described with reference to FIGS. 3 and 4.

Referring to FIG. 3, the PDP according to the embodiment of the present invention includes the phosphors 36R, 36G, and 36B having the same charging property as the ultraviolet light emitting phosphor material and the charging characteristic is positive.

The top plate of the PDP includes a sustain electrode pair 34 formed on the upper substrate 46, an upper dielectric layer 42 and a protective film 40 stacked on the upper substrate 46 on which the sustain electrode pair 34 is formed. do. Each of the sustain electrode pairs 34 includes a transparent electrode such as indium tin oxide (ITO), and a metal bus electrode having a line width smaller than that of the transparent electrode and formed at one edge of the transparent electrode. One of the sustain electrode pairs 34 serves as a scan electrode for selecting a scan line by supplying a negative scan pulse in an address period for selecting a cell. In the sustain electrode pair 34, sustain pulses are alternately supplied during the sustain period to cause sustain discharge for the cells selected by the address discharge. In the upper dielectric layer 42, wall charges generated during plasma discharge are accumulated. The passivation layer 40 is formed of a material such as MgO, thereby preventing damage to the upper dielectric layer 42 and the sustain electrode pair 34 due to sputtering generated during plasma discharge, and increasing emission efficiency of secondary electrons.

The lower plate of the PDP includes an address electrode 32 formed on the lower substrate 44, a lower dielectric layer 48 and a lower dielectric layer 48 deposited on the lower substrate 44 so as to cover the address electrode 32. And a partition wall 38 formed vertically from the lower dielectric layer 48 and phosphors 36R, 36G, and 36B formed on the surface of the partition wall 38. The address electrode 32 is orthogonal to the sustain electrode pair 34 and supplied with a positive data pulse synchronized with the scan pulse supplied to any one of the sustain electrode pair 34. The cell is selected by the address discharge occurring in the form of counter discharge between any one of the address electrode 32 and the sustain electrode pair 34. The partition wall 38 is formed in parallel with the address electrode 32 to prevent ultraviolet rays and visible light generated by the discharge from leaking to the adjacent discharge cells.

Phosphors 36R, 36G, 36B are applied to vacuum ultraviolet phosphors such as R: (YGd) BO ₃ : Eu ³⁺ , G: Zn ₂ SiO ₄ : Mn ²⁺ , B: BaMgAl ₁₀ O ₁₇ : Eu ²⁺ . UV light emitting phosphor material is mixed. Here, the ultraviolet light emitting phosphor material has a strong absorption edge in the vacuum ultraviolet region (VUV), the charging property of the surface is '+' and the phosphor having a light emission peak in the wavelength range of 200 ~ 400nm. In other words, the conventional phosphor consists only of a vacuum ultraviolet phosphor material excited to a vacuum ultraviolet ray having an excitation band of 147 nm or 173 nm, whereas the present invention provides a charge of an excitation band of 200 to 400 nm and is charged to a conventional vacuum ultraviolet phosphor. Ultraviolet phosphors with the characteristic '+' are mixed. Such ultraviolet phosphors include (Ba, Mg, Zn) ₃ SiO ₇ : Pb ²⁺ , (Ca, Zn) ₃ (PO ₄ ) ₂ : Tl ⁺ , MgO: Gd ³⁺ , Y ₂ O ₃ : Gd ^3+, and the like. There is this.

The ultraviolet phosphor is not limited to the above examples, but any phosphor having a light emitting center of Gd ³⁺ , Ce ³⁺ or Eu ²⁺ or another light emitting center and having a light emitting peak at an excitation band of 200 to 400 nm Anything is possible.

The mixing ratio of the phosphors 36R, 36G and 36B is 1 to 99% by weight compared to the vacuum ultraviolet phosphor, and the ultraviolet phosphor is mixed. On the other hand, the vacuum ultraviolet phosphor is not limited to R: (YGd) BO ₃ : Eu ³⁺ , G: Zn ₂ SiO ₄ : Mn ²⁺ , B: BaMgAl ₁₀ O ₁₇ : Eu ²⁺ , and the wavelength of the excitation band is 147 nm. Any phosphor that is excited by vacuum ultraviolet radiation of 173 nm is possible. For example, the vacuum ultraviolet phosphors other than the above compounds include Y ₃ Al ₅ O ₉ : Tb ³⁺ , Y ₂ SiO ₅ : Tb ³⁺ , SrAl ₂ O ₄ : Eu ²⁺ , (Ba, Sr, Mg) OaAl ₂ O ₃ : Mn, GdBO ₃ : Tb ³⁺ (where, in OaAl ₂ O ₃ , a is a natural number coefficient), YBO ₃ : Tb ³⁺ , BaAl ₁₂ O ₁₉ : Mn ²⁺ , Y ₂ O ₃ : Eu ³⁺ , Y ₂ SiO ₅ : Ce ³⁺ , Gd ₂ O ₃ : Eu ²⁺ , Y ₃ (Al, Ga) ₅ O ₁₂ : Tb ³⁺ , MgAl ₂ O ₄ : Eu ²⁺ , MgAl ₂ O ₄ : Mn ²⁺ , Mg ₂ SnO ₄ : Mn ²⁺ , Y ₄ Al ₂ O ₉ : Tb ³⁺ , YPO ₄ : Tb ³⁺ , YAlO ₃ : Tb ³⁺ , (YGd) BO ₃ : Tb ³⁺ , CaAl ₂ O ₄ : Eu ²⁺ , CaMgSi ₂ O ₆ : Eu ^2+, and the like.

As can be seen from FIG. 3, the PDP according to the present invention has the charging characteristics of all of the red, green and blue phosphors 36R, 36G, and 36B being positive, that is, '+' so that the electrons move toward the address electrode 2. Since it is free to move, the electrostatic repulsion against the electrons is minimized and there is almost no voltage drop during discharge. Therefore, the PDP according to the present invention has almost no charge delay in all of the phosphors 36R, 36G, and 36B having red, green, and blue charge characteristics, so that there is almost no discharge delay and the voltage required for discharge is minimized.

4 schematically shows the light emitting mechanism of the phosphors 36R, 36G, 36B according to the present invention.

Referring to FIG. 4, in the PDP according to the present invention, when a discharge is generated due to a voltage difference between two electrodes, the excitation energy of vacuum ultraviolet light (VUV) generated at the time of discharge is 147 nm and 173 nm, which are resonance lines of Xe. This vacuum ultraviolet ray (VUV) excites and emits a vacuum ultraviolet phosphor and an ultraviolet phosphor contained in the phosphors 36R, 36G, and 36B. At this time, the ultraviolet phosphor material emits light emitting energy in the 200-400 nm band, and the vacuum ultraviolet phosphor material adjacent thereto absorbs the light emitting energy in the 200-400 nm band generated from the ultraviolet phosphor material and emits excitation light again.

As described above, the phosphor of the PDP according to the present invention is excited by vacuum ultraviolet rays of 147 nm and 173 nm, and the ultraviolet fluorescent substance which has a charging characteristic of '+' and emits and is excited and emitted by energy in the band of 200 to 400 nm is emitted to the vacuum ultraviolet phosphor which emits light. Will be mixed. As a result, the phosphor of the PDP according to the present invention minimizes electrostatic repulsion to the electrons, excites and emits the vacuum ultraviolet phosphor with 147 nm and 173 nm vacuum ultraviolet rays, and emits energy in the 200-400 nm band generated from the ultraviolet phosphor material. By emitting light again, voltage drop and discharge delay can be minimized during discharge of the PDP, and address miss can be prevented. Furthermore, the PDP according to the present invention emits phosphors with the most excitation energy, so that the luminous efficiency is improved, as well as the charging characteristic is '+', which blocks the collision of cations, thereby extending the life.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the technical spirit of the present invention. Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification but should be defined by the claims.

Claims (8)

(Ba, Mg, Zn) ₃ SiO ₇ : Pb ²⁺ , (Ca, Zn) ₃ (PO ₄ ) ₂ : Tl ⁺ , MgO: Gd ³⁺ and Y ₂ O ₃ : phosphor of a plasma display panel, wherein an ultraviolet phosphor material of any one of Gd ³⁺ is mixed. The method of claim 1, And a vacuum ultraviolet phosphor which is mixed with the ultraviolet phosphor material and excited by the vacuum ultraviolet ray. The method of claim 2, The ultraviolet phosphor material is a phosphor of the plasma display panel, characterized in that the charging characteristics are positive. The method of claim 1, And said ultraviolet phosphor material is excited by energy of 200-400 nm wavelength. delete The method of claim 1, The light emitting center of the ultraviolet phosphor material is at least one of Gd ³⁺ , Ce ³⁺ and Eu ²⁺ phosphor of the plasma display panel. The method of claim 2, Wherein the ultraviolet phosphor material is mixed with the vacuum ultraviolet phosphor at 1 to 99% by weight relative to the vacuum ultraviolet phosphor. The method of claim 2, The vacuum ultraviolet phosphor is (YGd) BO ₃ : Eu ³⁺ , Zn ₂ SiO ₄ : Mn ²⁺ and BaMgAl ₁₀ O ₁₇ : Eu ²⁺ , Y ₃ Al ₅ O ₉ : Tb ³⁺ , Y ₂ SiO ₅ : Tb ³⁺ , SrAl ₂ O ₄ : Eu ²⁺ , (Ba, Sr, Mg) OaAl ₂ O ₃ : Mn, GdBO ₃ : Tb ³⁺ (wherein in OaAl ₂ O ₃ , a is the coefficient of natural number), YBO ₃ : Tb ³⁺ , BaAl ₁₂ O ₁₉ : Mn ²⁺ , Y ₂ O ₃ : Eu ³⁺ , Y ₂ SiO ₅ : Ce ³⁺ , Gd ₂ O ₃ : Eu ²⁺ , Y ₃ (Al, Ga) ₅ O ₁₂ : Tb ³⁺ , MgAl ₂ O ₄ : Eu ²⁺ , MgAl ₂ O ₄ : Mn ²⁺ , Mg ₂ SnO ₄ : Mn ²⁺ , Y ₄ Al ₂ O ₉ : Tb ³⁺ , YPO ₄ : Tb ^{3 +} , YAlO ₃ : Tb ³⁺ , (YGd) BO ₃ : Tb ³⁺ , CaAl ₂ O ₄ : Eu ²⁺ , CaMgSi ₂ O ₆ : Eu ²⁺ .