JPS63261665A - Flat fluorescent lamp - Google Patents

Abstract

PURPOSE:To strengthen the pressure-resistance of the lamp in the caption by lining-up plural glass tubes, where phosphor films are formed on their inside surfaces, on a plane in parallel to each other with discharge electrodes provided on both ends, while the upper and lower parts of the glass tubes are enclosed by flat glass plates provided so as to come in contact with the upper and lower end surfaces of the glass tube periphery, and the circumference is enclosed by a frame body for a spacer. CONSTITUTION:Plural glass tubes 4, where phosphor films 5 are formed on their inside peripheries 4e, are lined up in parallel to each other on a plane with discharge electrodes 6 and 6 provided on both ends, while the upper and lower parts of the glass tubes are enclosed by flat glass plates 1 and 2 provided so as to come in contact with the upper and lower end surfaces 4a and 4b while the circumference is enclosed with a frame body 3 for a spacer to form a hermetically sealed structure. Accordingly, the front glass plate 1 and the back glass plate 2 are supported by glass tubes 4 at prescribed plural spots so that power coming from the external atmospheric pressure is dispersed. Thereby, pressure-resistance is strengthened.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a flat fluorescent lamp used as a backlight for a liquid crystal display.

(Prior art) In flat fluorescent lamps, a voltage is applied between the electrodes to cause a discharge, and the mercury vapor contained within is excited and generates ultraviolet rays, which are applied to the back of the front and rear glass plates. The structure is such that the phosphor is excited and emitted light. In this fluorescent lamp, there is usually a space between the front and rear glass plates, and moreover, the space is almost in a vacuum state. For this reason, a large external pressure due to outside air pressure is applied to the glass surface, so when increasing the size of a fluorescent lamp, the plate thickness must be extremely large, resulting in an increase in weight.

Therefore, as shown in FIG. 4 as a plan view and as shown in FIG. 5 as a sectional view taken along the line A-A in FIG.
It is known that a plurality of ribs 14... are provided on the line connecting between the 6.
Publication No. 154).

These ribs 14... are connected to the rear glass plate 12 as shown in FIG.
It is provided by integral molding on the back surface, has a substantially triangular cross section, and its tip 14 a reaches the back surface of the front glass plate 11 .

(Problems to be solved by the invention) However, in such conventional flat fluorescent lamps,
The ribs 14... and the rear glass plate 12 need to be integrally molded, and the ribs 14... and the phosphor 15 of the front glass plate 11 tend to come into contact, so they must be sealed very carefully. This can easily cause problems in the process and reduce production efficiency.

In addition, in order to obtain uniform brightness, the phosphor 15 is attached to the front glass plate 1.
If the phosphor is applied only to the rear glass plate 12, it is difficult to increase the absolute brightness, and if the phosphor is applied to the rear glass plate 12 as well in order to increase the absolute brightness, the shadow of the rib having a substantially triangular cross section appears, making it impossible to obtain uniform brightness.

(Means and effects for solving the problem) In order to solve this problem, the present invention provides a fluorescent film 5 on the inner circumferential surface 4e.
A plurality of glass tubes 4... formed with... are arranged in parallel on a plane, discharge electrodes 6°6 are arranged at both ends, and the upper and lower ends of the glass tubes 4... are the upper and lower end surfaces 4a... of the outer circumference. 4b・
The planar glass plate 1.2 provided in contact with the spacer frame 3 forms a hermetically sealed structure around the flat glass plate 1.2.

According to such a configuration, the front glass plate 1 and the rear glass plate 2 are supported at a plurality of predetermined locations by the glass tubes 4 . . . , so that the force exerted by the external air pressure is dispersed, and their pressure resistance can be strengthened. Furthermore, since the precision of the diameter of the glass tube is sufficiently high during the manufacturing process, the assembly precision can be easily improved compared to conventional ribs. Furthermore, since there is no need to form a fluorescent film on the front glass plate, there is no need to worry about its peeling, and productivity and reliability can be improved.

(Example) Embodiments of the present invention will be described below based on the accompanying drawings.

FIG. 1 is a plan view showing a flat fluorescent lamp according to the present invention, and FIG.
The figures are a sectional view taken along the line B--B in FIG. 1, and FIG. 3 is a sectional view taken along the line C--C in FIG. 1.

In the figure, 1 is a front glass plate which is flat and forms an irradiation surface, 2 is a rear glass plate which is also flat and forms a non-irradiation surface, and 3 seals between each glass plate 1.2.
This is a frame for a spacer that is closely fitted between the peripheral edges of the glass plates 1 and 2 to seal mercury vapor and argon gas inside.

In the sealed space formed by the front glass plate 1, the rear glass plate 2, and the spacer frame 3, a glass tube 4 having a circular cross section extends its outer peripheral upper end surface 4a to the front glass plate 1. Then, the lower end surface 4b of the outer periphery is brought into contact with the rear glass plate 2, and the outer periphery both end surfaces 4C, 4d, . They are arranged in parallel on a plane in contact with the outer circumferential end surface 4d.-, 4 cm. Inner peripheral surfaces 4e of these glass tubes 4...
A phosphor 5 is applied to each of the phosphors 5 and 5. In addition, each glass tube 4... has the same length and is slightly shorter than the length between the opposing wall surfaces 3a and 3b of the frame tube 3, and the glass tube 4...
A pair of electrodes i, 6 are arranged between the ends 4f, 4g, . . . and the respective wall surfaces 3a, 3b.

Thus, the direction of the electric field due to the electrode 6.6 and the glass tube 4.
The axial directions of the glass tubes 4 are the same, and a discharge is carried out through the glass tube 4. to emit light.

In the drawings, 7 indicates a power supply, 8 indicates a lead wire, and 9 indicates a mercury getter containing mercury as an intermetallic compound for sealing mercury in a closed space during the manufacturing process. This is a chip tube installed in the

(Effects of the Invention) As is clear from the above description, according to the present invention, (i) The front glass plate and the rear glass plate are supported at a plurality of predetermined locations by glass tubes, so that the force exerted by external pressure is dispersed. , its pressure resistance can be strengthened.

(ii) Since the precision of the diameter of the glass tube can be obtained in the manufacturing process to be sufficiently high, the assembly precision can be easily improved compared to conventional ribs.

(ii) Since there is no need to form a fluorescent film on the front glass plate, there is no need to worry about its peeling, and productivity and reliability can be improved.

[Brief explanation of drawings]

FIG. 1 is a plan view showing a flat fluorescent lamp according to the present invention, and FIG.
The figures are a sectional view taken along line B-B in Figure 1, a sectional view taken along line C-C in Figure 1, and a plan view showing a conventional flat fluorescent lamp in Figure 4.
The figure is a sectional view taken along the line C--C in FIG. 1. In the drawing, 1 is a front glass plate, 2 is a rear glass plate, 3 is a frame for a spacer, 4 is a glass tube, 4a is an upper end surface of the glass tube, 4b is a lower end surface of the glass tube, and 4e is an inner surface of the glass tube. The peripheral surface 6 is a discharge electrode.

Claims (1)

[Claims] A plurality of glass tubes each having a fluorescent film formed on their inner peripheral surfaces are arranged in parallel on a plane, discharge electrodes are arranged at both ends, and the upper and lower sides of the glass tubes are provided in contact with the upper and lower end surfaces of the outer periphery of the glass tubes. A flat fluorescent lamp whose surroundings are sealed with a spacer frame.