JPH1069885A - Planar fluorescent lamp - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a phosphor from peeling on contact with electrodes by providing a banklike raised part at the boundary between the phosphor-coated part of a first or second glass substrate and an electrode position. SOLUTION: A phosphor 14 is applied to the center of each of front and rear glass substrates 9, 10, in each of which grooved parts 19 and raised parts 20 are formed. The phosphor 14 just applied is stopped by the banklike raised parts 20 and does not flow into the grooved parts 19 in which counter electrodes 15 are to be disposed. Next, the counter electrodes 15 are placed in the grooved parts 19 of the rear glass substrate 10, and the periphered edges 11 of the rear and front glass substrates 10, 9 are fused together by frit glass to form a sealed container. Therefore, the phosphor is not peeled on contact with the electrodes.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flat fluorescent lamp used for a backlight or the like of a liquid crystal display device.

[0002]

2. Description of the Related Art Flat fluorescent lamps are widely used in backlights of liquid crystal display devices and the like, and the structure of such a flat fluorescent lamp is, for example, as shown in FIGS. . In each of the figures, reference numeral 1 denotes a front glass substrate, 2 denotes a rear glass substrate, and a phosphor film 8 is formed on the inner surface of the rear glass substrate 2. The hermetically sealed container is formed by the front glass substrate 1 and the rear glass substrate 2. Make up.

[0005] Reference numeral 3 denotes a counter electrode disposed in a sealed container composed of the front glass substrate 1 and the rear glass substrate 2, and a mercury-containing getter material 6 is attached to one surface thereof.

[0005] Reference numeral 5 denotes a chip tube for exhausting air from the inside of a sealed container formed by the front glass substrate 1 and the rear glass substrate 2.

Next, the outline of the manufacturing process of the flat fluorescent lamp will be described. First, the counter electrodes 3 are respectively disposed in the rear glass substrate 2 and the front glass substrate 1 is positioned by a positioning jig or the like.
Then, positioning of the rear glass substrate 2 and the counter electrode 3 is performed.

Then, the front glass substrate 1 and the peripheral portion 4 of the rear glass substrate 2 are sealed with frit glass, and the air inside the container is evacuated from the cylindrical chip tube 5, and then the discharge gas is discharged. Inject into and chip off.

Thereafter, the getter material 6 of the mercury-containing type attached to the counter electrode 3 is heated to about 900 ° C. by high-frequency heating or the like, so that the getter material 6 is activated and mercury is expelled.

In order to emit light from the flat fluorescent lamp thus constructed, a high-frequency pulse voltage is applied to the lead piece 7 attached to the counter electrode 3 to excite the discharge gas. The phosphor film 8 is excited by energy to emit light uniformly.

[0009]

In the flat fluorescent lamp as described above, if the fluorescent material is applied to the vicinity of the electrode arrangement portion of the glass substrate, contact between the electrode and the fluorescent material during the manufacturing process. As a result, the phosphor may be peeled off, and the peeled-off phosphor may be scattered in the hermetically sealed container, thereby disturbing the emission of light or causing unevenness.

The present invention relates to a flat fluorescent lamp in which a sealed container is formed by first and second glass substrates coated with a fluorescent substance on an inner surface, and a pair of opposed electrodes are arranged in the sealed container. It is intended to prevent the peeling of the phosphor due to the contact between the electrode and the phosphor. ,

[0011]

In order to solve the above-mentioned problems, in the flat fluorescent lamp according to the present invention, the first or second glass substrate is provided with the phosphor-coated portion and the electrode disposing portion. A ridge-shaped ridge is provided at the boundary of.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 is an exploded perspective view showing the structure of a flat fluorescent lamp according to the present invention. FIGS. 2A and 2B
(C) (d) is a figure which shows the external appearance of the flat fluorescent lamp by this invention. FIG. 3 is a diagram showing a cross section taken along line XX 'of the flat fluorescent lamp shown in FIG. FIG. 4 is a view showing a YY ′ section of the flat fluorescent lamp shown in FIG. FIG. 5 is an enlarged view of a portion A in FIG.

In each of the drawings, reference numeral 9 denotes a front glass substrate as a first glass substrate, and 10 denotes a rear glass substrate as a second glass substrate.
0 is made of, for example, molded glass. A phosphor film 14 is formed on the inner surface of each glass substrate.
The sealed containers are formed by making the peripheral portions 11 of the respective glass substrates face each other and joining them using frit glass.

Reference numeral 13 denotes a chip tube for exhausting air in the sealed container and injecting a discharge gas, and 12 denotes a chip tube for inserting the chip tube 13 formed on the front glass substrate 9 and the rear glass substrate 10. It is a chip tube mounting concave portion that forms a through hole.

Numeral 15 is a counter electrode arranged to face each other. A getter material 16 of a mercury-containing type is attached to the counter electrode 15, and a lead piece 17 is attached to one end of the electrode. . Reference numeral 18 denotes a lead piece lead-out recess formed in the front glass substrate 9 and the rear glass substrate 10 to form a through hole through which the lead piece 17 passes.

Reference numeral 19 denotes a groove for positioning the counter electrode 15. Reference numeral 20 denotes a raised portion provided in parallel with the groove portion 19. Further, reference numeral 21 denotes a spacer projection formed in the groove 19.

The spacer projections 21 serve as the counter electrodes 15.
Of the front glass substrate 9 and the rear glass substrate 10 are minimized.

The height of the opposed electrode 15 (see FIG. 3) between the front glass substrate 9 and the rear glass substrate 10 after the assembly of the fluorescent lamp is completed and the height of the raised portion 20 is reduced by the raised portion 20. For the dimension Q (see FIG. 3), P <Q
It is configured to have the following relationship.

The phosphor film 14 is applied to the entire bottom surface of the sealed container except for the protruding portion 20 and the groove portion 19 on the inner bottom surface, and the portion where the phosphor film 14 is applied is further applied. Thickness t1 of front glass substrate 9 and rear glass substrate 10
And the thickness t2 of the portion where the groove 19 is formed is t2
<T1.

Next, the manufacturing process of the flat fluorescent lamp of the present invention will be described.

First, a phosphor 14 is applied to the central portions of the front glass substrate 9 and the rear glass substrate 10 in which the grooves 19 and the raised portions 20 are formed. At this time, the phosphor 14 immediately after the application has fluidity, but the fluid is not flowable.
0, and does not flow into the groove 19 where the counter electrode 15 is to be disposed later.

Next, each counter electrode 15 is arranged in the groove 19 of the rear glass substrate 10 and the lead piece 17 attached to one end of the counter electrode 15 is arranged in the lead piece lead-out recess 18. Further, the tip tube 13 is connected to the tip tube mounting recess 1.
After that, the peripheral portions 11 of the rear glass substrate 10 and the front glass substrate 9 are sealed with frit glass to form a sealed container.

Next, after the air inside the sealed container is exhausted through the chip tube 13, a discharge gas is injected into the sealed container through the chip tube 13 to chip off.

After that, the mercury-containing getter material 16 attached to the counter electrode 15 is heated to 900 ° C. by high-frequency heating or the like.
Approximately, the getter material 16 is activated and mercury is expelled.

To discharge the fluorescent lamp thus constructed, a high-frequency pulse voltage is applied from a lead piece 17 attached to the counter electrode 15 to excite the discharge gas, and the energy is used to excite the discharge gas. The phosphor film 14 is excited to emit light uniformly.

The lead piece 17 is used only for the purpose of applying a high-frequency pulse voltage since the counter electrode 15 is already positioned in the sealed container. It is attached by welding or the like.

In the flat fluorescent lamp having the above structure,
Since the opposing electrode 15 is sandwiched (positioned) by the groove 19, the opposing electrode 15 can be positioned without using a special electrode positioning jig or the like.

Further, since the lead piece 17 is attached to only one end of the counter electrode 15, when the peripheral edge 11 of each glass substrate is sealed with frit glass, thermal expansion of the glass substrate and the lead piece is performed. There is no tension due to the difference in the coefficients, and there are problems such as the detachment of the welded portion between the counter electrode 15 and the lead piece 17 and the leakage of the sealing part of the lead piece 17 (the lead piece lead-out recess 18). Does not occur.

Further, the counter electrode 15 is partially supported by the spacer portion 21 and a portion where the counter electrode 15 contacts the front glass substrate 9 and the rear glass substrate 10 is minimized. Problems such as cracks in the glass substrate due to thermal shock generated when the material 16 is heated by high frequency heating or the like can be prevented.

The thickness t of the front glass substrate 9 and the rear glass substrate 10 where the phosphor film 14 is applied
1 and the thickness t2 of the portion where the groove 19 is formed is t2
<T1, and the counter electrode 15 and the outer surfaces of the front glass substrate 9 and the rear glass substrate 10 are designed to be closer to each other. As a result, a flat fluorescent lamp that is thinner than a conventional lamp can be realized.

Further, a counter electrode 15 and a near conductor 22 provided for the purpose of assisting lighting in this type of discharge tube are provided.
(See FIG. 3 and FIG. 4) and the distance between the
The discharge impedance between the conductor 5 and the adjacent conductor 22 is reduced, which is effective in improving the starting performance of the flat fluorescent lamp.

As shown in FIG. 3, since the gap distance P between the raised portions 20 of each glass substrate has a relationship of P <Q with respect to the height dimension Q of the counter electrode 15, The discharge current when the lamp is lit mainly flows to the center of the electrode,
Therefore, the discharge from the electrode edge portion is suppressed, and there is also an effect of suppressing sputtering (blackening of the tube end).

[0034]

According to the present invention, a sealed container is formed by the first and second glass substrates coated with a phosphor on the inner surface, and a pair of opposed electrodes are arranged in the sealed container. In a fluorescent lamp, peeling of the phosphor due to contact between the electrode and the phosphor is prevented, and disturbance of light emission due to scattering of the peeled phosphor into the sealed container is also prevented.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing the structure of a flat fluorescent lamp according to the present invention.

FIG. 2 is a plan view showing the appearance of the flat fluorescent lamp according to the embodiment of the present invention.

FIG. 3 is a sectional view of a main part of a flat fluorescent lamp according to an embodiment of the present invention.

FIG. 4 is a sectional view of a main part of a flat fluorescent lamp according to an embodiment of the present invention.

FIG. 5 is an enlarged view of a main part of the flat fluorescent lamp according to the embodiment of the present invention.

FIG. 6 is an exploded perspective view showing the structure of a conventional flat fluorescent lamp.

FIG. 7 is a sectional view of a main part showing the structure of a conventional flat fluorescent lamp.

[Explanation of symbols]

 Reference Signs List 9 front glass substrate (first glass substrate) 10 rear glass substrate (second glass substrate) 11 peripheral portion 12 chip tube mounting recess 13 chip tube 14 phosphor film 15 counter electrode 16 getter material 17 lead piece 18 recess lead One-sided concave portion 19 Groove portion 20 Raised portion 21 Spacer protrusion 22 Proximity conductor

Claims (2)

[Claims] 1. A flat fluorescent lamp comprising: a sealed container formed by first and second glass substrates having a fluorescent material applied to an inner surface thereof; and a pair of opposed electrodes disposed in the sealed container. A flat fluorescent lamp characterized in that a bank-like raised portion is provided on a boundary between the phosphor coating portion and the electrode disposing portion of the first or second glass substrate. 2. The flat fluorescent lamp according to claim 1, wherein a groove is formed in the electrode arrangement portion of the glass substrate having the raised portion, in which the pair of electrodes are fitted.