JPH0278147A - Planar fluorescent lamp - Google Patents

Abstract

PURPOSE:To secure a required strength of a planar fluorescent lamp as a whole by sealing the open end of a bottomed metallic container airtightly with a planar glass plate of light transmitting property and forming irregularities on the bottomed metallic container. CONSTITUTION:An airtight container 30 is constituted in a flattened box shape with a metallic tray 21 with its top open end covered with a glass plate 29 of a rectangular shape corresponding to the external shape of the flange 22 of the metallic tray 21, a required thickness, light transmitting property, being made of soda lime glass, and with the mating surfaces of the flange 22 and the glass plate being airtightly secured together with glass frit or the like. A plurality of raised portions 32 are formed to project from the bottom 21a to the inside of the metallic tray 21 for example in a circular shape by means of a press process or the like. Between the adjacent raised portions 32, relatively recessed portions 33 are formed. As a result, the moment of inertia of the bottom 21a of the metallic tray 21 is increased with the irregularities 32, 33 so that the strength of the bottom 21 can be increased.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to a flat fluorescent lamp suitable for backlighting a liquid crystal display panel such as a liquid crystal television from the back side. The present invention relates to a flat fluorescent lamp whose airtight container is constituted by a shaped glass plate and a metal bottomed container.

(Prior Art) In recent years, LCD televisions have been developed and are becoming more popular, but this type of LCD television requires an LCD panel to display the TV image and a backlight to illuminate the panel from the back. As, over the entire display surface of a given area -
The ability to provide lighting with varying brightness is required.

Conventionally, such backlights are made by arranging multiple U-shaped fluorescent lamps or small straight tube fluorescent lamps in parallel, and combining them with light reflecting surfaces, light diffusing surfaces, etc.
Some devices are designed to reduce the brightness distribution by 1q.

However, when a plurality of such fluorescent lamps are used, it is inevitable that the brightness near the lamps will be higher than other parts, and it is difficult to eliminate overall brightness unevenness.

In addition, since multiple fluorescent lamps are used, the structure for holding these lamps and the structure for connecting to the power supply becomes complicated, which increases the number of parts, increases the size of the fixture, and especially makes the backlight itself thicker and thinner. There is a drawback that it cannot be formalized.

For example, there is a flat fluorescent lamp constructed as shown in FIG. 5 to solve this problem.

As shown in FIG. 5, this flat fluorescent lamp includes a front plate 1-1 made of a single transparent plate glass, a back plate 2 made of a single plate glass of the same shape and size, and these plates 1, 2 and a glass spacer 3 assembled into a rectangular frame of the same shape and size.

The front plate 1 has a fluorescent film 4 coated almost entirely on its inner surface (lower surface in FIG. 5), and its outer surface serves as a light-emitting surface, and the back plate 2 has a light-diffusing layer on its inner surface (upper surface in FIG. 5). The film 5 and the light reflection 116 are deposited in two layers, upper and lower.

As shown in FIG. 6(A), the front plate 1 and the back plate 2 are hermetically joined to the upper and lower openings of the spacer 3 by means of a low-melting glass frit 7, forming an airtight thin flat box shape. Constructs a container 8 and includes a front plate 1
A liquid crystal panel, such as a liquid crystal television (not shown), is arranged above so as to closely face it from the back side.

Hence the front play! 1 faces the back plate 2 with a spacer 3 in between, and a discharge space 9 is formed between both plates 1 and 2 as shown in FIG.

In this discharge space 9, a pair of discharge electrodes 10, 10, such as a hollow cathode type cold cathode, are arranged facing each other and spaced apart from each other. , these mouth-shaped openings 0 are opposed to each other.

Further, the pair of electrodes 10.10 has a pair of lead pieces 11.11 integrally extending outward in the axial direction from the outer ends in the axial direction, and the tip of each lead piece 11 is shown in FIG. 6(A).

As shown in (B), it extends airtightly to the outside of the airtight container 8 and is connected to a power source, a lighting circuit, etc. (not shown).

Reference numeral 12 in FIG. 5 is an exhaust pipe, and the airtight container 8 contains at least one kind of rare gas such as xenon, krypton, argon, neon, helium, etc., or in some cases, this rare gas and a predetermined amount of gas. Contains mercury.

In the flat fluorescent lamp configured in this way, when a predetermined voltage is applied between the pair of electrodes 10 and 10, a glow discharge occurs between the two electrodes 10 and 10, and this glow discharge causes the inside of the airtight container 8 to be Mercury is excited in the discharge space 9 to generate ultraviolet rays, which excites the fluorescent film 4 of the front plate 1, and visible light is emitted from the light emitting surface on the outer surface of the front plate 1. The back of the screen is illuminated in a planar manner.

In addition, the ultraviolet rays generated inside the airtight container 8 are exposed to the back side].
The light is diffused and reflected by the light diffusing film 5 and the light reflecting film 6 of No. 2, and is guided to the fluorescent film 4, where the light is emitted and the luminous efficiency is reduced.

Therefore, since the entire front panel 1 emits light almost uniformly, there is little unevenness of 11 degrees.

(Problem to be Solved by the Invention) However, in such a conventional flat fluorescent lamp, the back plate 2 is made of thick plate glass like the front plate 1, so the overall thickness of the flat fluorescent lamp becomes thick. This increases the weight, which is disadvantageous for flat fluorescent lamps that are required to be thin and lightweight.

In addition, both the upper and lower openings of the glass spacer 3 are cooled by the front and back plates 1.2 of the sheet glass, and each joint surface is fixed by the glass frit 7, so there is no misalignment or gap at each joint. There is a problem that the probability of occurrence increases and the airtightness of the airtight container 8 decreases.

The present invention has been made in consideration of the above circumstances, and its object is to provide a thin and lightweight flat fluorescent lamp having the required strength.

(Structure of the Invention) (Means for Solving the Problems) The present invention provides a method for producing metal oxide film using a flat glass plate having translucency.
l! ! The open end of the J bottomed container was hermetically sealed to form an airtight container, a pair of discharge electrodes and a discharge gas were sealed in this airtight container, and a plurality of irregularities were formed in the metal bottomed container. Features (effects): Since an airtight container is constructed by airtightly sealing the open end of a metal bottomed container with a plate glass, by reducing the plate thickness of this metal bottomed container, The entire flat fluorescent lamp can be made thinner and lighter.

In addition, since we formed multiple unevenness on the metal bottomed container,
The section modulus of the gold-Xil bottomed container can be increased to improve its strength, and the required strength of the flat fluorescent lamp as a whole can be ensured.

(Example) The present invention will be explained in detail below.

FIG. 2 is an exploded perspective view of an embodiment of the present invention, and in the figure, a metal container 21 formed into a rectangular dish-shaped metal container with a bottom from a metal H material such as iron or stainless steel is shown at its open upper end. Seven flange 22 having a rectangular outer shape and projecting outward are integrally provided on the flange.

The metal vessel 21 has a pair of rectangular cylindrical discharge electrodes 23a inside.
, 23b are accommodated at the left and right ends in the figure, and each ri pole 23a,
The flange 22 has lead piece recesses 25a and 25b into which the lead pieces 24a and 24b protruding from one end in the axial direction (the front end in FIG. 2) of the flange 23b are fitted in an airtight and electrically insulated manner.
gold fl[[11
The tips of each lead piece 24a, 24b extending outward from 21 are electrically connected to a lighting circuit or the like.

In FIG. 3, each lead piece 24a, 24b is connected to each lead piece recess 2.
5a and 25b in an airtight and electrically insulated state; This prevents each lead piece 24a, 24b from electrically shorting to gold ff1l'm21.

In addition, a downwardly convex arc-shaped recess 28 is formed in the longitudinally intermediate portion of the front portion (the front side in FIG. 2) of the flange 22, into which the intermediate portion of the cylindrical lJt trachea 27, which is open at both ends, is airtightly fitted. , an exhaust pipe 27 allows communication between the inside and outside of the metal device 21.

The upper end of the opening of the metal vessel 21 is covered concentrically with a rectangular flat glass plate 29 made of translucent soda lime glass or the like and having a required thickness that matches the external dimensions of the seven flange 22 of the metal vessel 21. As shown in FIG. 1, the container 30 is constructed into a flat, thin, box-shaped airtight container 30, and the joint surfaces of the seven flange 22 and the glass plate 29 are hermetically fixed with glass frit or the like.

A fluorescent film 31 is completely coated on the inner surface of the glass plate 26,
The air inside the metal vessel 21 is exhausted through an exhaust pipe 27, and rare gas and mercury are sealed inside the metal vessel 21.

The bottom 21a of the metal utensil 21 has a plurality of, for example, circular convex portions 32 protruding inwardly formed by press molding, and there are relatively concave portions 33 between adjacent convex portions 32. It is formed.

Therefore, the bottom portion 21a of the metal vessel 21 has a concave portion and a convex portion 33.
Since the section modulus is increased by 32, the strength of the bottom portion 21a can be increased.

Further, an electrically insulating film 34 made of glass or the like is deposited on the entire inner surface of the bottom 21a of the metal vessel 21, and a pair of electrodes 23a, 23b are attached.
This prevents the discharge from short-circuiting to the metal device 21 when a discharge occurs between the metal devices 21 and 21.
It is possible to prevent impurity gas from being released from the lamp and reducing lamp efficiency.

Next, the operation of this embodiment will be explained.

When a required voltage is applied between the pair of electrodes 23a and 23b in the airtight container 30, a planar discharge occurs between them 23a and 23b over almost the entire length, and this discharge excites mercury atoms. to generate ultraviolet light.

The ultraviolet rays uniformly excite the fluorescent film 31 on the inner surface of the glass plate 29 almost entirely to emit visible light, which passes through the glass plate 29 and is emitted to the outside.

Since a part of the airtight container 30 is constituted by the metal vessel 21, it is possible to improve the processing accuracy and ease of processing this 1 ml of gold [121], and to reduce the plate thickness of the metal vessel 21. As a result, the flat fluorescent lamp as a whole can be made thinner and lighter.

Moreover, the bottom 21a of the metal utensil 21 has a plurality of uneven portions 3.
3.32 to increase the section modulus, the strength of the bottom portion 21a and the metal vessel 21 as a whole can be increased.

The flat fluorescent lamp shown in Fig. 4 is similar to the one shown in Figs.
This is a modification of the flat fluorescent lamp shown in the figure, and the metal vessel 21
The bottom portion 21a of the
The feature is that a light reflection/diffusion film 4o is entirely coated on the inner surface, and an insulating film 34 is further coated on the entire upper surface of this light reflection/diffusion film 40, except for this. Since the structure is similar to that in FIG. 4, the same reference numerals are given to the parts in FIG. 4 that are common to those in FIGS.

According to this embodiment, among the ultraviolet rays generated by the metal vessel 21, the ultraviolet rays emitted to the bottom 21a of the metal vessel 21 are reflected and diffused 11! The fluorescence lI on the inner surface of the glass plate 29 is reflected and diffused by J40! 31 and emit light there, the brightness can be improved compared to the case where the light reflection/diffusion film 40 is not provided.

〔Effect of the invention〕

As explained above, the present invention has constructed an airtight container by hermetically sealing the front end of the metal bottomed container with a plate glass. The lamp as a whole can be made thinner and lighter, and since the metal bottomed container has multiple irregularities, the strength of the metal bottomed container can be improved, making it possible to achieve a flat fluorescent lamp. The required strength as a whole can be ensured.

[Brief explanation of the drawing]

1 is a longitudinal sectional view of an embodiment of the flat fluorescent lamp according to the present invention, FIG. 2 is an exploded perspective view of the embodiment of FIG. 1, and FIG. 3 is a partial longitudinal sectional view of the embodiment of FIG. 4 is a vertical sectional view showing a modification of the embodiment shown in FIG. 1, FIG. 5 is an exploded perspective view of a conventional flat fluorescent lamp, and FIG. 6 (A) is a conventional planar fluorescent lamp shown in FIG. FIG. 2B is a front view of the fluorescent lamp in an assembled state; FIG. 21... Metal appliance (metal bottomed container), 22... Flange, 23a, 23b... Discharge electrode, 29... Glass plate, 30... Airtight container, 32... Convex part, 33...
- Concave portion, 34... Insulating film, 40... Light reflection/diffusion film. Applicant's agent Hisashi Hatano Figure 3 IK4 Figure 5 (A) (B) Figure 6

Claims (1)

[Claims] The open end of a metal bottomed container is hermetically sealed with a flat glass plate having translucency to form an airtight container, a pair of discharge electrodes and a discharge gas are sealed in this airtight container, and the metal A flat fluorescent lamp characterized by having a bottomed container formed with a plurality of irregularities.