KR20030076877A - Fluorescent lamp for using back light - Google Patents

Abstract

PURPOSE:A fluorescent lamp used for a backlight is provided to prevent the performance of the fluorescent lamp from lowering due to deterioration of a fluorescent substance by not forming the fluorescent substance at external walls of both ends of a transparent tube of the fluorescent lamp. CONSTITUTION:A transparent tube(31) is formed in one direction. A plurality of external electrodes(32a,32b) are formed at external walls of both ends of the transparent tube to which power is applied. A fluorescent substance(33) is coated on the whole inner surface except the external electrodes.

Description

Fluorescent lamp used for backlight {FLUORESCENT LAMP FOR USING BACK LIGHT}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to fluorescent lamps, and more particularly to fluorescent lamps used in backlights for liquid crystal display devices.

CRT (Cathode Ray Tube), one of the commonly used display devices, is mainly used for monitors such as TVs, measuring devices, and information terminal devices.However, due to the weight and size of the CRT itself, Could not respond actively to demands.

Therefore, in the trend of miniaturization and weight reduction of various electronic products, CRT has a certain limit in weight and size, and is expected to replace the liquid crystal display device (LCD) using the electro-optic effect, and gas discharge. There are plasma display panels (PDPs) and electroluminescent displays (ELDs) using electroluminescent effects, among which researches on liquid crystal displays (LCDs) are being actively conducted.

In order to replace the CRT, liquid crystal display devices having advantages such as small size, light weight, and low power consumption have been actively developed. In recent years, an ultra-thin flat display display having a thickness of only a few centimeters (Cm) is used. Developed enough to fulfill its role as a device, it is used in spacecraft, aircraft, laptop computers, laptop computer monitors, desktop computer monitors, and large information display devices. The demand for liquid crystal display devices continues to increase. to be.

Since most of the liquid crystal display devices are light-receiving devices that display an image by controlling the amount of light coming from the outside, a separate light source, that is, a backlight, is required for irradiating light onto the LCD panel. It is divided into edge type and direct type according to the installed position.

In the double-edge method, the lamp unit is installed on the side of the light guide plate for guiding the light, and the lamp unit covers a lamp emitting light, a lamp holder inserted at both ends of the lamp to protect the lamp, and an outer circumferential surface of the lamp, and one side It is provided with a lamp reflector plate fitted to the side of the light guide plate to reflect the light emitted from the lamp toward the light guide plate.

The edge method in which the lamp unit is installed on the side of the light guide plate is applied to a relatively small liquid crystal display device such as a monitor of a laptop computer and a desktop computer, and has good uniformity of light and a long service life. It is advantageous to thin the liquid crystal display device.

On the other hand, the direct type method has been developed mainly as the size of the liquid crystal display device has increased to 20 inches or more, and a plurality of lamps are arranged in a row on the lower surface of the diffuser plate to direct light directly to the front of the LCD panel. will be.

The direct method is mainly used for a large screen liquid crystal display device requiring high luminance because the light utilization efficiency is higher than that of the edge method.

In the case of the liquid crystal display device adopting the direct method, it is used as a large monitor or a TV, and the use time is longer than that of a laptop computer, and when the use time is longer, the lamp deteriorates. May shorten the lifespan and affect the characteristics of the liquid crystal display. Currently, research is being conducted to prevent this phenomenon.

Hereinafter, a fluorescent lamp used for a conventional backlight will be described with reference to the accompanying drawings.

1 is a perspective view of a backlight for a conventional liquid crystal display device, a perspective view of a direct type backlight, and FIG. 2 is a view showing a fluorescent lamp according to the prior art.

As shown in FIG. 1, a conventional backlight for a liquid crystal display device includes a plurality of fluorescent lamps 1, an outer case 3 for fixing and supporting the fluorescent lamps 1, and the fluorescent lamp 1. And light scattering means 5a, 5b, 5c disposed between the liquid crystal panel (not shown).

The light scattering means 5a, 5b, 5c are arranged to prevent the shape of the fluorescent lamp from appearing on the display surface of the liquid crystal panel and to provide a light source having an overall uniform brightness distribution, and to enhance the light scattering effect. A plurality of diffusion sheets, diffusion plates, and the like are disposed between the panels.

The inner surface of the outer case 3 is disposed with a reflector 7 so that the light emitted from the fluorescent lamp 1 can be concentrated to the display unit of the liquid crystal panel, which is to maximize the utilization efficiency of the light.

Both sides of the fluorescent lamp 1 are fitted in grooves formed on both sides of the outer case 3 as shown in the drawing.

Power leads 9 and 9a for transmitting power for driving the lamps are connected to both electrodes of the fluorescent lamp 1, and the power leads 9 and 9a are connected to a separate connector and connected to a driving circuit. For each fluorescent lamp 1, a separate connector is required.

The fluorescent lamp 1 emits light when power is applied to an external electrode formed at both ends of the fluorescent lamp.

In this case, as shown in FIG. 2, the external electrodes 22a and 22b are disposed on the outer walls of both ends of the transparent tube 21, and the fluorescent lamp 1 is formed on the entire inner wall including both inner walls of the transparent tube 21. (23) is coated.

When the external electrodes 22a and 22b are turned on to emit light, an external electrode fluorescent lamp driven by connecting several lamps in parallel under the same conditions has a higher voltage than a cold cathode tube lamp connected to an inverter for each lamp. Will be used.

The fluorescent lamp used in the conventional backlight as described above has the following problems.

Since a high voltage is applied to the external electrode of the external electrode fluorescent lamp, the fluorescent material in the portion may deteriorate, thereby deteriorating the characteristics of the fluorescent lamp and shortening the lifespan.

The present invention has been made to solve the conventional problems as described above, in particular, it is used in a backlight suitable for preventing the lamp characteristic is reduced and the life is shortened due to deterioration of the phosphor coated on the inner wall of the tube (Tube) The purpose is to provide a fluorescent lamp.

1 is a perspective view of a conventional direct backlight

2 is a view showing a fluorescent lamp according to the prior art

3A illustrates a fluorescent lamp according to a first embodiment of the present invention.

3b is a view showing a fluorescent lamp according to a second embodiment of the present invention

Explanation of symbols on the main parts of the drawings

31: transparent tube 32a 32b: external electrode

33: phosphor

Fluorescent lamp used in the back light of the present invention for achieving the above object comprises a transparent tube having one direction, the phosphor is coated on the inner wall of the transparent tube except for both ends of the transparent tube to be applied power. It features.

Hereinafter, a fluorescent lamp used in the backlight of the present invention will be described with reference to the accompanying drawings.

3A is a view showing a fluorescent lamp according to a first embodiment of the present invention, Figure 3B is a view showing a fluorescent lamp according to a second embodiment of the present invention.

The present invention can be applied to an external electrode fluorescent lamp having electrodes formed on both ends of a tube, and an electrodeless fluorescent lamp having no electrodes formed on a tube.

First, the fluorescent lamp according to the first embodiment of the present invention will be described.

The fluorescent lamp according to the first exemplary embodiment of the present invention has a transparent tube 31 having one direction as shown in FIG. 3A, and external electrodes 32a and 32b are formed on outer walls of both ends of the transparent tube 31. The phosphor 33 is coated on the entire inner wall of the transparent tube 31 except for the external electrodes 32a and 32b.

In this case, the external electrodes 32a and 32b on the outer walls of both ends of the transparent tube 31 may be made of aluminum tape, copper tape, silver, or a plating material.

As described above, the reason why the phosphor 33 is coated only on the inner wall of the transparent tube 31 except for the external electrodes 32a and 32b is that the phosphor coated on the external electrode portion is deteriorated, thereby degrading the characteristics of the lamp. To prevent it.

Next, a fluorescent lamp according to a second embodiment of the present invention will be described.

The fluorescent lamp according to the second embodiment of the present invention is an electrodeless fluorescent lamp that does not form an external electrode in the lamp itself, as shown in FIG. 3B, and has a transparent tube 31 having one direction and a portion to which external power is applied. The phosphor 33 is coated on the entire inner wall of the transparent tube 31 except for both ends of the transparent tube 31 which is an external electrode.

As described above, the coating of the phosphor 33 only on the inner wall of the transparent tube except for the external electrode portion, as described in the first embodiment, causes the phosphors at both ends of the transparent tube to be applied from the outside to be deteriorated, thereby degrading lamp characteristics. To prevent it.

The fluorescent lamp configured as in the first and second embodiments is a fluorescent lamp together with the first and second lower mechanisms having a plurality of grooves for accommodating both ends of the fluorescent lamp, and the first and second lower mechanisms. The first and second upper mechanisms having the same grooves formed at positions corresponding to the first and second lower mechanisms, and the grooves of the first, second upper and lower mechanisms are formed to fix and support the 31. It can be applied to a backlight composed of a conductive layer formed to apply power to both ends of the fluorescent lamp.

In the backlight, the first and second lower mechanisms may be coated with a material having a separate reflective material or a diffuse reflective material on an inner surface thereof, or the first and second lower mechanisms may serve as reflectors for reflecting light. It can be configured to be.

Referring to the method for forming a fluorescent lamp having the above configuration is as follows.

First, a transparent tube having one direction and having one end opened is formed, and a phosphor is coated on the entire inner wall of the opened transparent tube, and then both ends of the inner tube (or both ends of the transparent tube to which power is applied from the outside) on which the external electrode is to be formed. Removing the phosphor with an airbrush or a brush, vacuuming the transparent tube, adding neon, argon and mercury gas, and then sealing one end of the opened transparent tube.

Subsequently, in order to form an external electrode fluorescent lamp, a conductive material is applied to both ends of the transparent tube from which the phosphor is removed.

The fluorescent lamp used in the present invention as described above has the following effects.

By preventing the phosphor from being formed on the inner walls of both ends of the transparent tube of the fluorescent lamp to which the power is applied, the phenomenon of deterioration of the phosphor and deterioration of the lamp can be prevented.

Claims (5)

Transparent tube having one direction, And a phosphor coated on an inner wall of the transparent tube except for both ends of the transparent tube to which power is applied. The method of claim 1, Fluorescent lamp used in the backlight, characterized in that the external electrode is further disposed on the outer wall both ends of the transparent tube not coated with the phosphor. The method of claim 1, The fluorescent lamp is a fluorescent lamp used in the backlight, characterized in that further comprising using an electrodeless fluorescent lamp, the external electrode is not formed at both ends. Transparent tube having one direction, External electrodes formed on outer walls of both ends of the transparent tube, And a fluorescent substance coated on an inner wall of the transparent tube except for an inner wall of both ends of the transparent tube in which the external electrode is formed. The method of claim 4, wherein The external electrode is a fluorescent lamp used in a backlight, characterized in that composed of aluminum tape, copper tape, silver or plating material.