JPH0650625B2 - Flat fluorescent lamp - Google Patents

Description

The present invention relates to a flat fluorescent lamp suitable as a backlight for a liquid crystal display device or a liquid crystal TV device in a word processor, a personal computer or the like.

(B) Conventional technology Since liquid crystal panels are advantageous in that they are light and thin and consume little power, they are widely used as display devices such as personal computers or word processors in addition to liquid crystal TVs. On the other hand, since the liquid crystal itself does not emit light, it is necessary to use a flat fluorescent lamp as described in Japanese Utility Model Publication No. 54-111985 (93D311).

In addition, the liquid crystal panel has become larger in size in recent years and, for example, A4 size ones have come to be used, and it has become necessary to increase the size of a flat fluorescent lamp used in such a large liquid crystal panel. . However, if the glass container is made large, it is necessary to use a thick glass plate in order to prevent the implosion due to the atmospheric pressure, which has a drawback that it hinders the reduction in weight and thickness.

In order to solve the above-mentioned drawbacks, the applicant of the present invention previously filed Japanese Patent Application No.
Japanese Patent No. 1-54194 proposes a flat fluorescent lamp in which a reinforcing glass is provided between a pair of upper and lower flat glass plates which face each other to increase the withstand pressure and enable a reduction in thickness.

However, when relatively inexpensive soda glass, lead glass, borosilicate glass, or the like is used as the reinforcing glass, ultraviolet rays (253
7Å) cannot be transmitted. Therefore, since the fluorescent film applied to the inner surface of the upper flat glass facing the reinforcing glass does not emit light, the brightness of the portion where the reinforcing glass is located on the light emitting surface is reduced by blocking or turning off the light by this fluorescent film. And the brightness unevenness occurs.

(C) Problems to be Solved by the Invention The present invention has been made in view of the above points, and provides a flat fluorescent lamp in which uniform brightness is obtained without uneven brightness even when using a reinforcing glass. To do.

(D) Means to solve the problem The present invention, the reinforcing glass is a cylindrical one with a fluorescent film formed on its inner surface, and an auxiliary electrode is provided on the discharge pole,
The auxiliary electrode is located inside the reinforcing glass.

(E) Function In the present invention, the fluorescent film in the reinforced glass tube is excited by the discharge of the auxiliary electrode to emit light.

(F) Embodiment One embodiment of the present invention will be described below with reference to the drawings.

1 (a), (b) and (c) are plan views of the flat fluorescent lamp in this embodiment, a sectional view taken along the line AA ', a sectional view taken along the line BB', and FIG. 2 is a perspective view of the discharge pole. FIG. 3 is an enlarged sectional view of the reinforced glass.

In the figure, (1) and (2) are upper and lower flat glass sheets of A4 size (278 mm × 192 mm) having fluorescent films (3) and (4) formed on the inner surfaces thereof, respectively, and the fluorescent film (3) has a slit-like shape. Uncoated part (5) (5)
It is divided into three parts. The upper surface of the upper flat glass (1) is roughened. (6) is a rectangular frame glass that holds the upper and lower flat glasses at a predetermined interval, and constitutes a glass container together with the upper and lower flat glasses.

(7) (7) is a discharge pole with a U-shaped cross section as shown in FIG. 2, and both sides have a flat plate-shaped first for promoting discharge at the ends.
Auxiliary electrodes (7a) and (7a) and rod-shaped second auxiliary electrodes (7b) and (7b), a part of which is inserted into a reinforcing glass described later, are formed, respectively.

(8) (8) is a lead piece having an L-shaped cross section which is connected to the first auxiliary electrode by spot welding and protrudes to the outside, and has a function of mechanically supporting the discharge pole in addition to its electrical function. Also has.

(9) (9) is a cylindrical reinforcing glass having a height equal to the gap between the upper and lower flat glass plates as shown in FIG. 3, and prevents implosion. The reinforced glass is fixed to the lower flat glass (2) by a fritted glass and faces the upper flat glass (1) along the uncoated portions (5) and (5) thereof. Further, the fluorescent film (10) is formed on the inner surface of the reinforcing glass (9), and the discharge of the second auxiliary electrode allows light emission even in the reinforcing glass tube.

(11) is a chip tube in which the inside of the glass container is exhausted and argon gas and mercury are allowed to flow in, and then the tip is sealed by heat fusion.

Next, a procedure for assembling the flat fluorescent lamp will be described.

First, the uncoated parts (5) (5) on the inner surfaces of the upper and lower flat glass (1) (2)
Then, the fluorescent films (3) and (4) are formed by screen printing while leaving. Then, the discharge glass electrode (7) (7) with the fritted glass, the reinforcing glass (9) (9) and the chip pieces (8) (8) attached at a predetermined position on the lower flat glass (2) is placed, Further, the frame glass (6), the chip tube (11) and the upper flat glass (1) are placed together with the fritted glass to form a hermetically sealed glass container by heat fusion.

Finally, the air in the container is evacuated through the chip pipe (11) and argon gas and mercury are introduced, and the tip is heat-sealed to seal it.

In operation of the above flat fluorescent lamp, the fluorescent film (10) inside the reinforcing glass (9) is excited by the discharge of the second auxiliary electrode (7b) to emit light, and this light is emitted from the reinforcing glass (9) and the uncoated portion. Since it passes through (5) and the upper flat glass (1) and is radiated to the outside, the brightness of the portion where the reinforcing glasses (9) and (9) are located on the light emitting surface does not decrease.

(G) Effect of the Invention According to the present invention as described above, since the reinforcing glass itself emits light, uniform brightness can be obtained on the light emitting surface without any decrease in brightness at the portion where the reinforcing glass is located. Therefore, it is extremely effective as a backlight for a display device such as a liquid crystal TV, a personal computer or a word processor.

[Brief description of drawings]

1 (a), (b) and (c) are plan views of a flat fluorescent lamp in one embodiment of the present invention, a sectional view taken along the line AA 'and a sectional view taken along the line BB', and FIG. A perspective view and FIG. 3 are enlarged sectional views of the reinforced glass. (1) (2) …… Upper and lower flat glass, (3) (4) (10) …… Fluorescent film,
(5) (5) …… No coating, (6) …… Frame glass, (7) (7) …… Discharge electrode, (7a) (7a) …… First auxiliary electrode, (7b) (7b) ) …… Second
Auxiliary electrode, (9) (9) …… Reinforced glass.

Front page continuation (72) Inventor Katsumi Terada 2-18 Keihan Hondori, Moriguchi City, Osaka Sanyo Electric Co., Ltd. Within

Claims (1)

[Claims] 1. A pair of discharge glass electrodes are arranged to face each other in a glass container in which a pair of flat glass sheets having a fluorescent film formed on their inner surfaces face each other with a predetermined spacing, and a space between the pair of flat glass sheets. In a flat fluorescent lamp in which a reinforcing glass having substantially the same height as that of the reinforcing glass is arranged substantially parallel to a line connecting the pair of discharge poles, the reinforcing glass has a cylindrical shape with a fluorescent film formed on its inner surface. A flat fluorescent lamp in which an auxiliary electrode is provided on the discharge pole and the auxiliary electrode is located inside the reinforcing glass.