Electric lamp and discharge devices – With gas or vapor – Three or more electrode discharge device
Reexamination Certificate
2001-11-28
2004-10-26
Bruce, David V. (Department: 2882)
Electric lamp and discharge devices
With gas or vapor
Three or more electrode discharge device
C313S495000, C445S024000, C445S025000
Reexamination Certificate
active
06809476
ABSTRACT:
This application claims the benefit of the Korean Application No. P2000-71689 filed on Nov. 29, 2000, which is hereby incorporated by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a plasma display panel, and more particularly, to a plasma display panel and a method for fabricating the same.
2. Discussion of the Related Art
In accordance with the advent of the multimedia era, a display device that can display a natural color has been required. Particularly, a plasma display panel has lately attracted considerable attention an advanced display device because a current cathode ray tube (CRT) or a liquid crystal display (LCD) has limitations in realizing a large sized display of 40 inch or greater.
A typical plasma display panel, as shown in
FIGS. 1A and 1B
, includes an upper substrate
10
and a lower substrate
20
which face each other.
FIG. 1C
illustrates a sectional structure of the plasma display panel, in which the lower substrate
20
is rotated by 90° for the convenience.
The upper substrate
10
includes scan electrodes
16
and
16
′, sustain electrodes
17
and
17
′, a dielectric layer
11
, and a passivation layer
12
. The scan electrodes
16
and
16
′ are formed in parallel to the sustain electrodes
17
and
17
′. The dielectric layer
11
and the passivation layer
12
are sequentially formed on the upper substrate
10
including the scan electrodes
16
and
16
′ and the sustain electrodes
17
and
17
′.
The lower substrate
20
includes address electrodes
22
, a dielectric layer
21
, barriers
23
, and a phosphor
24
. The dielectric layer
21
is formed on an entire surface of the lower substrate including the address electrodes
22
. The barriers
23
are formed on the dielectric layer
21
between the respective address electrodes
22
. The phosphor
24
is formed on surfaces of the barriers
23
and the dielectric layer
21
in each discharge cell.
Inert gases such as He and Xe are mixed in a space between the upper substrate
10
and the lower substrate
20
. The space forms a discharge area.
The operation of the aforementioned plasma display panel will now be described.
If a driving voltage is applied between each address electrode and each scan electrode, opposite discharge occurs between the address electrode
22
and the scan electrodes
16
and
16
′. Some electrons emitted from the inert gas within the discharge cell come into collision with a surface of the passivation layer due to the opposite discharge. The collision of the electrons secondarily emits electrons from the surface of the passivation layer. The secondarily emitted electrons come into collision with a plasma gas to diffuse the discharge. If the opposite discharge between the address electrode
22
and the scan electrode
16
and
16
′ ends, wall charges having opposite polarities occur on the surface of the passivation layer on the respective address and scan electrodes.
If the discharge voltages having opposite polarities are continuously applied to the scan electrodes
16
and
16
′ and the sustain electrodes
17
and
17
′ and at the same time the driving voltage applied to the address electrode
22
is cut off, area discharge occurs in a discharge area on the surfaces of the dielectric layer and the passivation layer due to the potential difference between the scan electrodes
16
and
16
′ and the sustain electrodes
17
and
17
′. The electrons in the discharge cell come into collision with the inert gas in the discharge cell due to the opposite discharge and the area discharge. As a result, the inert gas in the discharge cell is excited and ultraviolet rays having a wavelength of 147 nm occur in the discharge cell. The ultraviolet rays come into collision with the phosphors surrounding the address electrode and the barriers, so that the ultraviolet rays are emitted, thereby displaying a picture image.
Therefore, to obtain an improved performance and a longer life span, the plasma display panel should have rigid internal films and no mixed gases except for the discharge gases.
A method for fabricating the aforementioned plasma display panel includes three fabricating processes such as a prior process, a later process, and a module process.
In the prior process, various films are formed in the upper and lower substrates
10
and
20
. In the later process, attachment of the upper and lower substrates
10
and
20
, exhaust, injection of a discharge gas, tip-off, aging, and test are implemented. The tip-off is implemented in such a manner that exhaust and injection of a discharge gas are implemented through an exhaust pipe and then the exhaust gas is cut and sealed. The aging is to apply a power source to an electrode, drive the panel for a predetermined time, and finally remove impurities, thereby obtaining a discharge voltage drop effect.
Finally, in the module process, a circuit is mounted and assembled to complete the plasma display panel.
The method for fabricating the related art plasma display panel will now be described with reference to
FIGS. 2A
to
2
C.
As shown in
FIGS. 2A
to
2
C, the upper and lower substrates
10
and
20
are fed to the attachment equipment, and a sealant
30
, i.e., frit is deposited along a boundary of the upper or lower substrate using a dispenser. The frit consists of glass, SiO
2
, and an additive for improving adhesion.
The upper and lower substrates are dried at a temperature of about 120° C. and fired at a high temperature of 400° C. or greater to remove the impurities remaining in the frit.
The fired upper and lower substrates are fed to the attachment equipment in a state that the upper substrate
10
is exposed to the air.
As shown in
FIG. 2B
, the upper substrate
10
and the lower substrate
20
are aligned in the attachment equipment and then fixed by a nipper
50
for attachment. Then, the frit is fused, so that the upper substrate
10
and the lower substrate
20
are attached to each other as shown in FIG.
2
C.
Also, a long straw shaped exhaust pipe
40
of glass is attached to an exhaust hole (not shown) of the lower substrate
20
using a frit ring (not shown) during the attachment process.
Next, the attached substrates are fed to an exhaust and gas injection equipment. The exhaust and gas injection equipment exhausts out mixtures stuck to the film and mixed gases generated in the film using the exhaust pipe
40
under high vacuum and heating conditions.
The discharge gas is injected through the exhaust gas
40
and heat is applied to the end of the exhaust gas
40
so as not to leak the injected discharge gas, thereby melting the end of the exhaust gas
40
to implement the tip-off process.
Then, the aging is carried out and then the status of the panel is tested. Thus, the process of fabricating the plasma display panel is completed.
As described above, in the exhaust pipe type fabrication equipment, a separate type fabrication equipment separately carries out the attachment process, the exhaust process, and the gas injection process. The separate type fabrication equipment includes an attachment equipment and an exhaust and gas injection equipment. The exhaust and gas injection equipment includes a hot blast furnace (not shown) for forming exhaust and discharge gas injection conditions, and a cart (not shown) for loading a panel (not shown), carrying out exhaust and discharge gas injection within the hot blast furnace, and unloading the panel.
The cart has a complex structure that includes a vacuum pump (not shown) putting the panel under vacuum state, a vacuum pipe system consisting of an exhaust manifold (not shown), a valve and a pipe arrangement, a discharge gas injection bombe (not shown), a gas injection pipe system consisting of a gas injection manifold (not shown), a valve and a pipe arrangement, and a tip-off unit (not shown) for implementing tip-off of the exhaust pipe
40
.
However, the method for fabricating the related art plasma display panel has several problems.
First, the fir
Lee Mi Kyoung
Shin Kui Sung
Bruce David V.
Keaney Elizabeth
LandOfFree
Plasma display panel and method for fabricating the same does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Plasma display panel and method for fabricating the same, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Plasma display panel and method for fabricating the same will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3306470