JP2000348632A - Luminance increasing method for plasma display panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To use luminescence to a backside to increase luminance of a display by installing a reflector on which ratio of diffuse reflectance to reflectance of a total light ray is in a specific range % on the backside of a display panel. SOLUTION: A reflector 140 is installed on a glass substrate on the opposite side of a display-side surface 120 of a plasma display panel 110, and luminescence to a backside 130 is used to increase luminance. In addition, using the reflector 140 on which ratio of diffuse reflectance to reflectance of a total light ray is in a range from 0.1% to 50%, luminance is increased without affecting image quality. The reflector 140 is installed on at least the backside 130, of the display-side surface 120 and the backside 130 of the plasma display panel 110. The reflector 140 may be formed directly on the backside 130 of the plasma display panel 110, or the pre-produced reflector 140 is installed or adhered, with an adhesive, onto the backside 130 of the plasma display panel 110.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a method for improving the brightness of a plasma display. More specifically, the present invention relates to a method for effectively utilizing light emission to the back surface, which has not been used so far, in a plasma display device which mainly focuses on viewing from the front surface among plasma displays, and to improve the luminance.

[0002]

2. Description of the Related Art A plasma display is a display device utilizing light emission at the intersection of matrix electrodes due to plasma discharge of a rare gas. Since it is easy to enlarge the screen and can be made thinner, it has attracted attention as a wall-mounted display together with a liquid crystal display (LCD) and the like. The plasma display panel has AC electrodes covered with a dielectric layer.
There is a type and a DC type in which the electrodes are exposed to the discharge space. FIG. 1 shows an example of an AC type plasma display panel. In the AC type plasma display panel, a display electrode 20 composed of a pair of scanning electrodes and sustaining electrodes is formed on a front glass substrate 10 in a shape orthogonal to the address electrodes 70, and a dielectric layer 30 for AC driving is protected. MgO layers 40 as layers are respectively formed. On the other hand, a stripe-shaped insulating barrier 60 is formed on the rear glass substrate 50, and an address electrode 70 is further formed in parallel with the insulating barrier.
0, a green phosphor layer 90, and a blue phosphor layer 100 are sequentially formed. In the display, a mixed gas of, for example, Ne and Xe, or a mixed gas of He and Xe is placed in a discharge space composed of two glass substrates provided with these display electrodes and address electrodes and an insulating barrier.
The mixed gas composed of e is filled with several hundred Torr, discharged in a discharge space, and the phosphor is excited by the ultraviolet rays generated by the discharge to emit light.

[0003] The plasma display was originally made for military purposes in the United States, and had the characteristic of being viewed from both sides. However, at the time of application to home wall-mounted televisions and the like, light emission to the back surface is not effectively used because of single-side display. As a method of improving the brightness of a plasma display,
Improvements are being made to the PDP structure itself, the driving method, the circuit, the electrode material and structure, the phosphor material and coating method, and the discharge gas composition and pressure. Improving brightness is an important issue in suppressing power consumption and improving contrast.

[0004]

SUMMARY OF THE INVENTION The present invention relates to a single-sided plasma display such as a home wall-mounted television.
It is an object of the present invention to effectively use light emission on the back surface, which has not been effectively used so far, thereby improving the brightness of the plasma display.

[0005]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies in order to solve the above-mentioned problems. It has been found that, by providing a reflector, light emission to the back surface, which has not been used before, can be used and the luminance can be improved. Furthermore, it has been found that by using a reflector in which the ratio of the diffuse reflectance to the total light reflectance is 0.1% or more and 50% or less, the luminance can be improved without affecting the image quality. The present invention has been made based on such findings.

That is, the present invention provides (1) a method for improving the brightness of a plasma display, which is characterized in that a reflector is provided on the back surface of a plasma display panel, and (2) the ratio of diffuse reflectance to total light reflectance is zero. .1% or more 50
%. A method for improving the brightness of a plasma display as described in (1), characterized in that a reflector having a density of not more than% is used.

First, an example of an installation position of a reflector used in the present invention will be described with reference to FIG. The reflector 140 is provided on the display side surface 120 and the back surface 13 of the plasma display panel 110.
0, it is installed at least on the back surface 130 side. The reflector may be formed directly on the back surface 130 side of the plasma display panel, or a reflector prepared in advance may be installed on the back surface of the plasma display panel or bonded using an adhesive or the like.

As a method of forming the reflector directly on the back surface 130 side of the plasma display panel, there is a method of forming a metal on the back surface 130. For example, as a method for forming silver, there are a wet method and a dry method. The wet method is a general term for a plating method, and is a method of forming a film by depositing silver from a solution. Specific examples include a silver mirror reaction. On the other hand, the dry method is a general term for a vacuum film forming method, and specific examples thereof include a resistance heating type vacuum deposition method, an electron beam heating type vacuum deposition method, an ion plating method, and an ion beam assisted vacuum deposition method. And a sputtering method.

[0009] Examples of the reflector prepared in advance include a reflector having a metal formed on a polymer substrate and a metal plate. Examples of a method for forming a metal on a polymer substrate include the above-mentioned wet method and dry method. In particular, when a metal is formed on a polymer substrate, a vacuum film forming method capable of a roll-to-roll method of continuously forming a film is preferably used. As the metal used as the reflective layer, aluminum, silicon, titanium, chromium, nickel, copper, zinc, palladium, silver,
Tungsten, gold and the like can be used, but any metal having excellent reflectance in the visible region may be used. Among them, silver and aluminum which can obtain a high reflectance in the entire visible region are particularly preferably used.

As the reflector, a reflector having a low diffuse reflectance and a strong regular reflection (specular reflection) is preferably used. Preferably, the ratio of diffuse reflectance to total light reflectance is 50% or less, and more preferably, the ratio of diffuse reflectance to total light reflectance is 30% or less. An excessively large ratio of the diffuse reflectance to the total light reflectance is not preferable because a displayed image is blurred. The lower limit of the ratio of the diffuse reflectance to the total light reflectance is preferably as small as possible. It is preferably at least 0.1%, more preferably at least 0.01%, even more preferably at least 0.001%.

[0011]

The present invention will be described below with reference to examples. The total light reflectance and diffuse reflectance of the reflector were measured by installing a 150φ integrating sphere on a Hitachi automatic recording spectrophotometer (U-3400). A standard white plate made of aluminum oxide was used as a standard sample (reference). In the present invention, the values at the wavelength of 550 nm were used for the total light reflectance and the diffuse reflectance unless otherwise specified.

Example 1 Silver was deposited to a thickness of 150 nm on a 50 μm-thick polyester film (PET) by DC magnetron sputtering to produce a PET / silver reflector. The reflector was placed on the back of the plasma display panel. In addition, it installed so that PET surface might be the plasma display panel side.

Example 2 A 0.3 mm-thick aluminum plate slightly hairlined was placed on the back surface of a plasma display panel using an adhesive sheet.

Comparative Example 1 No reflector was provided on the back surface of the plasma display panel.

Comparative Example 2 A 50 μm-thick polyester film (PET) subjected to sandplast processing was
Silver was deposited to a thickness of 150 nm by an evaporation method to produce a reflector made of PET / silver. The reflector was placed on the back of the plasma display panel. In addition, it installed so that PET surface might be the plasma display panel side.

The ratio of the diffuse reflectance of the reflector used in the above Examples and Comparative Examples to the total light reflectance (diffuse reflectance /
Table 1 shows the total light reflectance), the display surface luminance of the plasma display in the above Examples and Comparative Examples, and the results of image blur evaluation. From this, it can be seen that in the example, the luminance of the display surface is greatly increased and the image is not blurred.
On the other hand, in Comparative Example 2, the increase in the luminance of the display surface was small compared to the Example, and blurring of the image was observed.

[0017]

[Table 1]

[0018]

By installing a reflector on the back surface of the plasma display panel, it was possible to improve the display surface brightness without deteriorating the image quality.

[Brief description of the drawings]

FIG. 1 shows an example of an AC type plasma display panel.

FIG. 2 shows an example of an installation position of a reflector used in the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 10 front glass substrate 20 display electrode 30 dielectric layer 40 MgO layer 50 rear glass substrate 60 insulating barrier 70 address electrode 80 red phosphor layer 90 green phosphor layer 100 blue phosphor layer 110 plasma display panel 120 display side surface 130 back surface 140 reflection body

Claims (2)

[Claims] 1. A method for improving the brightness of a plasma display, comprising: installing a reflector on the back surface of a plasma display panel. 2. The method for improving brightness of a plasma display according to claim 1, wherein a reflector having a ratio of diffuse reflectance to total light reflectance of 0.1% or more and 50% or less is used.