JP4881541B2 - Flat fluorescent lamp - Google Patents

Description

The present invention relates to a backlight for a liquid crystal display, which is attached to the back surface of a liquid crystal display and irradiates the back surface of the liquid crystal display to generate luminance on the display surface of the liquid crystal display that does not emit light. Specifically, the present invention relates to a flat fluorescent lamp for a large backlight intended for large liquid crystal televisions and the like.

The current backlight for liquid crystal displays is a combination of multiple cold-cathode fluorescent lamps and an acrylic light guide plate. However, light loss due to the light guide plate and an increase in the area of the liquid crystal display As a result, the increase in the number of cold cathode fluorescent lamps used is a problem. A flat fluorescent lamp that serves as a backlight for a liquid crystal display with a single lamp has hitherto been difficult to put into practical use. As an example, the 1-inch type flat fluorescent lamp for liquid crystal backlight described in Non-Patent Document 1 can be produced, but the 5-inch type cannot withstand the external pressure.
Nikkei Hi-Tech Information 90.7.2 New Product Topics 21 pages

The problem to be solved by the present invention is to provide a flat fluorescent lamp that has a structure capable of withstanding an external pressure even in a large area, has a uniform surface brightness, and can emit light brightly even at a low temperature.

As a means for realizing a structure that can withstand external pressure even in a large area, the present invention forms a corrugated parallel groove on the front glass substrate and the rear glass substrate constituting the flat fluorescent lamp, and thereby the pressure resistance performance of the glass substrate. To solve the problems.

Next, as a means for making the surface brightness uniform, an appropriate interval is set so that the wavy parallel grooves formed on the front glass substrate and the rear glass substrate described above do not contact inside the lamp. The problem is solved by causing the phosphor coating film formed on the inner surface of the wavy parallel grooves to emit light entirely by discharging with an electrode provided so as to face the lateral side of the lamp.

And as a means to realize a flat fluorescent lamp that can emit light brightly even at low temperatures, a heater wire is installed in the lamp on the lower side of the flat fluorescent lamp so that the evaporation of encapsulated mercury is activated even below freezing point. , To solve the problem.

The present invention achieves the means for solving the above-mentioned problems by realizing the best mode for carrying out the invention described later, thereby having a structure that can withstand external air pressure even in a large area, and having a uniform surface luminance. Thus, it is possible to realize a flat fluorescent lamp for a large backlight which can emit bright light even at a low temperature and is intended for a large liquid crystal television or the like.

The best mode for carrying out the present invention is a rectangular front glass in which corrugated parallel grooves are formed on the entire surface excluding the welded portion on the outer periphery and a member mounting portion such as an electrode, and a phosphor coating film is formed on the inner surface side. When the outer periphery of the substrate and the rear glass substrate is welded through a glass frame to form a lamp envelope, and the lamp envelope is set upright, an exhaust pipe is attached to the glass frame on the upper side of the installation , and the lamp envelope previously sealed prior to forming, the glass frame which faces the installation lateral side, the lighting lead-in wire welded a plurality of sets of cylindrical electrodes to oppose, at appropriate intervals, pre-sealed prior to the lamp bulb formed The heater lead wire with one or more heater wires connected to the glass frame on the lower side of the installation is sealed in advance before forming the lamp envelope. Structure that can withstand atmospheric pressure, uniform surface brightness, and bright even at low temperatures It is an achievable light capable flat fluorescent lamp.

As shown in FIGS. 1, 2 and 3, the first embodiment as the best mode for carrying out the present invention has a wavy parallel groove on the entire surface excluding the welded portion on the outer periphery and the member mounting portion such as an electrode. The outer peripheral portion of the rectangular front glass substrate 1 and the rear glass substrate 2 formed with the phosphor coating film 4 on the inner surface side is welded via the glass frame 3 to form a lamp seal, and the wavy parallel When the lamp envelope is installed upright so that the groove is vertically long , the exhaust pipe 5 is sealed in advance on the glass frame 3 on the upper side of the installation before the lamp seal is formed , and the opposing glass on the lateral side of the installation the frame 3, a lighting lead-in wire 6 welded a plurality of sets of cylindrical electrodes 7 so as to face, at appropriate intervals, pre-sealed prior to the lamp bulb formed, the glass frame 3 to be placed lower, one or more sets of the heater lead wire 8 connected to the heater wire 9, before the lamp bulb formed Is obtained by the order sealed structure, with the structure to withstand the outside pressure even in a large area, the surface brightness is uniform, and makes it possible achieve a bright light emission can be flat fluorescent lamp even at a low temperature.

Now, Example 1 will be described in more detail. As shown in FIGS. 1 and 2, the best mode for realizing a flat fluorescent lamp having a structure capable of withstanding an external pressure even in a large area is a welded portion on the outer periphery of the front glass substrate 1 and the rear glass substrate 2, and members such as electrodes. This is a structure in which wavy parallel grooves are formed on the entire surface excluding the mounting part, which improves the pressure resistance of the glass substrate and makes it possible to realize a flat fluorescent lamp with a structure that can withstand external pressure even in a large area. It is. It should be noted that an appropriate interval is set so that the inner surface of the front glass substrate 1 and the rear glass substrate 2 on which the wavy parallel groove phosphor coating film 4 is formed does not come into contact.

As shown in FIGS. 1, 2, and 3, the best mode of the exhaust pipe 5 is to seal the glass tube to the glass frame 3 on the upper side of the flat fluorescent lamp to form the exhaust pipe 5. Yes, it is possible to exhaust a flat fluorescent lamp and enclose inert gas (not shown) such as neon and argon and mercury (not shown). Further, the effect of sealing on the upper side of the installation can prevent mercury from entering and staying in the exhaust pipe 5. In addition, the exhaust pipe 5 shown in FIG.1 and FIG.3 shows the sealed form.

As shown in FIGS. 1, 2, and 3, the best mode for realizing a flat fluorescent lamp with uniform surface brightness is to face the opposing glass frame 3 on the lateral side of the flat fluorescent lamp. The lighting lead-in wire 6 to which the three sets of cylindrical electrodes 7 are welded is sealed at an appropriate interval, and voltage is applied to the lighting lead-in wire 6 by three sets of lighting devices (not shown). Three rows of fluorescent discharges are generated between the three sets of cylindrical electrodes 7. That is, the phosphor coating film formed on the inner surface of the corrugated parallel grooves is caused by three rows of glow discharges running across the inner surface side of the corrugated parallel grooves set in the longitudinal direction of the front glass substrate 1 and the rear glass substrate 2. 4 is caused to emit light. As described above, by setting an appropriate interval on the inner surface side where the phosphor coating film 4 of the wavy parallel grooves of the front glass substrate 1 and the rear glass substrate 2 is formed, the light emitting surface of the phosphor coating film 4 is continuous. Thus, a flat fluorescent lamp with uniform surface brightness can be realized. When the area of the flat fluorescent lamp is further increased, the lamp sealing body is increased in area, and the lighting introduction lines 6 to which the cylindrical electrodes 7 are welded are further increased from three sets.

Here, before explaining the best mode for realizing a flat fluorescent lamp capable of emitting light brightly even at a low temperature, the low temperature lighting of the fluorescent lamp will be described. When the ambient temperature is below freezing point, it is generally difficult to brightly illuminate a fluorescent lamp. The reason is that the mercury in the lamp does not evaporate sufficiently below freezing, so that ultraviolet rays are not generated and the phosphor coating film does not emit light sufficiently. In particular, in a flat fluorescent lamp, mercury that had evaporated during lighting is cooled down when the lamp is extinguished and stays at the lower side of the lamp installation, so there is almost no mercury on the upper side of the lamp. It becomes difficult.

As shown in FIGS. 1 and 3, the best mode for realizing a flat fluorescent lamp capable of emitting light brightly even at a low temperature is provided with a heater wire on a glass frame 3 on the lower side when the flat fluorescent lamp is installed upright. 9 is connected to the heater lead wire 8 and the heater wire 9 is energized through the heater lead wire 8 to heat the mercury accumulated at the lamp installation lower side when the lamp is turned off. It is possible to achieve a flat fluorescent lamp that can emit light brightly even at low temperatures. Note that one or more sets of heater introduction wires 8 connected to the heater wires 9 are sealed in accordance with the area of the flat fluorescent lamp. Here, it is desirable that the heater wire 9 be a round wire or a strip wire as shown in FIGS. 1 and 3 and connected via a leaf spring 10 to prevent slack. The material of the heater wire is generally tungsten, molybdenum or the like, but zirconium is particularly optimal. Zirconium causes a getter action in the range of approximately 200 degrees Celsius to approximately 600 degrees Celsius. Therefore, by using zirconium, together with the heater action, carbon dioxide, carbon monoxide, and water vapor, which are residual harmful gases in the lamp by the getter action. Etc. can be removed, and further improvement in the performance and quality of the flat fluorescent lamp can be expected.

In Example 2 as the best mode for carrying out the present invention, as shown in FIGS. 4 and 5, a wavy parallel groove is formed on the entire surface excluding a welded portion on the outer periphery and a member mounting portion such as an electrode, The outer peripheral portions of the rectangular front glass substrate 1 and the rear glass substrate 2 having the phosphor coating film 4 formed on the inner surface side are welded via the glass frame 3 to form a lamp envelope, and the wavy parallel grooves are horizontally long. When the lamp envelope is set up so as to become, the exhaust pipe 5 is sealed in advance on the glass frame 3 which is the upper side of the installation before the lamp seal is formed , and the opposite glass frame 3 which is on the lateral side of the installation. The lighting lead wires 6 in which a plurality of sets of cylindrical electrodes 7 are welded so as to face each other are pre- sealed at appropriate intervals before the lamp seal is formed , and one set or a plurality of sets of heater lead wire 8 connected to the heater wire 9, pre-sealed prior to the lamp bulb formed It was is obtained by the structure, in the structure to withstand the outside pressure even in a large area, the surface brightness is uniform, and makes it possible achieve a bright light emission can be flat fluorescent lamp even at a low temperature.

As described above, in Example 1, when the lamp envelope is installed upright, the wavy parallel grooves are set to be vertically long, whereas in Example 2, the lamp envelope is installed upright. The wavy parallel grooves are set so as to be horizontally long, and as shown in FIGS. 4 and 5, a plurality of sets are provided so as to face the opposing glass frame 3 on the lateral side of the flat fluorescent lamp. In sealing the lead-in lead 6 for lighting to which the cylindrical electrode 7 is welded at an appropriate interval, at the approximate center of the tunnel-shaped space formed on the inner surface side by the wavy parallel grooves of the front glass substrate 1 and the rear glass substrate 2. By aligning, a fluorescent discharge similar to a general fluorescent lamp can be realized. By setting an appropriate interval on the inner surface of the front glass substrate 1 and the rear glass substrate 2 on which the wavy parallel groove phosphor coating film 4 is formed, the light emitting surface of the phosphor coating film 4 becomes continuous. Similar to the first embodiment, a flat fluorescent lamp with uniform surface brightness can be realized. Except as described above, the embodiment is the same as that of Example 1, and the performance as a flat fluorescent lamp is also substantially the same, and thus detailed description thereof is omitted.

In recent years, competition for development of liquid crystal displays in Japan, Korea, and Taiwan has become increasingly active, and liquid crystal displays and their backlights are expected to develop more and more as an industry. If the flat fluorescent lamp is successfully developed and mass-produced, it is considered that it will be used as a backlight.

It is a top view which shows Example 1 of the flat fluorescent lamp by this invention. It is AA sectional drawing of FIG. It is BB sectional drawing of FIG. It is a top view which shows Example 2 of the flat fluorescent lamp by this invention. It is CC sectional drawing of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Front glass substrate 2 Rear glass substrate 3 Glass frame 4 Phosphor coating film 5 Exhaust pipe 6 Lighting introduction line 7 Cylindrical electrode 8 Introduction line for heater 9 Heater line 10 Leaf spring

Claims (3)

A front glass substrate (1) having a wavy parallel groove formed in a portion excluding the outer peripheral portion to be welded, and a rear glass substrate (2) having a wavy parallel groove formed in a portion excluding the outer peripheral portion to be welded The wavy parallel grooves formed on the front glass substrate (1) and the wavy parallel grooves formed on the rear glass substrate (2) extend in the same direction, so that the glass frame (3 ) To form a lamp envelope,
A phosphor coating film (4) is formed on the inner surfaces of the front glass substrate (1) and the rear glass substrate (2),
An exhaust pipe (5) is sealed to a portion of the glass frame (3) constituting one side surface portion extending in a direction perpendicular to the direction in which the wavy parallel grooves extend, and the wavy parallel grooves extend. One or more sets of one or more sets of cylindrical electrodes (7) connected to one or more sets of opposing cylindrical electrodes (7), respectively, are located on the opposing glass frame (3) constituting the side portions extending in a direction parallel to the direction . The lighting lead-in line (6) is sealed,
A round line or band extending along the portion of the glass frame (3) constituting the other side surface portion extending in a direction perpendicular to the direction in which the wavy parallel grooves extend inside the lamp envelope. One or more heater wires (9) consisting of wires are mounted,
The one or more heater wires (9) are connected to the part of the glass frame (3) constituting the other side surface portion extending in a direction perpendicular to the direction in which the wavy parallel grooves extend. A flat fluorescent lamp, wherein one or a plurality of sets of heater introduction wires (8) are sealed . The front glass substrate (1) and the rear glass substrate (1) and the rear glass substrate (1) and the inner surface of the rear glass substrate (2) are spaced apart from each other without contact with each other. 2) and three or more pairs of the cylindrical electrodes facing each other at the portions of the facing glass frame (3) that respectively constitute side portions extending in a direction parallel to the direction in which the wavy parallel grooves extend. 3. The flat fluorescent lamp according to claim 1, wherein three or more sets of lighting lead-in wires (6) connected to (7) are sealed.   3. The flat fluorescent lamp according to claim 1, wherein the heater wire (9) is made of zirconium.

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