JPH02244553A - Low pressure mercury vapor discharge lamp - Google Patents

Abstract

PURPOSE:To vary the color of emitted light even through a single light source is used, by accommodating a plurality of light emitting thin tube in a discharge space, coating the inside surfaces of these thin tubes with fluorescent substance films giving different colors, arranging openings of the thin tubes adjoining one another, and furnishing a common electrode closely facing these openings. CONSTITUTION:A plurality of, for ex. three, light emitting thin tubes 7, 8, 9 are accommodated in a discharge space 6. These thin tubes 7, 8, 9 are fixed onto a stem 5 in the condition that their bends 10 face a spherical part 4, that their other end openings 16 are in attitude as facing the stem 5, and that the openings 16 are adjoining one another, and an electrode 11 is located at one end of these thin tubes 7, 8, 9. The inner surface of them are coated with fluorescent substance films 17, 18, 19 emitting different mono-chromatic beams, for ex. red, green and blue. Because the openings 16 of the thin tubes are adjoining one another and a common electrode is furnished closely facing them, possible loss in the part not contributing to light emission of the fluorescent substance can be lessened.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention can be used as a light source arranged in large numbers on display screens installed in baseball stadiums or stadiums, or as a light source used as a single tube for lighting effects. Regarding low pressure mercury vapor discharge lamps.

[Technical background of the invention and its problems]

Recently, television cameras and video cameras are being used at baseball fields and stadiums.
A display device is installed that projects and displays images stored in the TR on a large display screen. This device displays a predetermined image on the display screen by disposing thousands to tens of thousands of light sources densely on the display screen and selectively turning on these light sources in accordance with image signals. It looks like this.

By the way, as for this type of light source, the current type R-beam emits a single color of blue, green, or red, and the color light bulb coated with translucent paint emits blue, green, or red light. Products that emit light in a single color are known.

However, although the electron beam has advantages such as low power consumption and long life, it has the disadvantage that the light source itself is expensive, resulting in high cost. In addition, although light bulbs have the advantage that the light source itself is inexpensive and the control circuit is simple,
On the other hand, it has drawbacks such as high power consumption and short life span. Note that such a drawback is not limited to the case where the display screen is provided. For example, traditionally covered light bulbs are
Although it is used as a light source for displaying performances in stores, stages, etc., the above-mentioned drawbacks have arisen even in such use.

Therefore, it is conceivable to use a low-pressure mercury vapor discharge lamp, typified by a fluorescent lamp, as another light source. It is well known that fluorescent lamps consume less power, have a long life, have high brightness, and are relatively inexpensive, so from this point of view, they are sufficient to meet the requirements as a light source. I can say it.

On the other hand, conventional light sources for display or performance display are red,
A set of three light sources that emit blue and green light are used. Therefore, each color of red, blue, and green is 1
If a single light source can emit light, the entire light source for three colors can be made more compact and the cost can be reduced.

[Purpose of the invention]

The present invention was made based on these circumstances, and
The purpose of the present invention is to provide a low-pressure mercury vapor discharge lamp that has a single light source but whose emission color can be changed appropriately depending on the purpose and method of use.

[Summary of the invention]

That is, in order to achieve the above object, the present invention accommodates a plurality of light emitting thin tubes each having an electrode at one end and having an open end at the other end in a discharge space formed within a transparent outer tube, A phosphor film that emits light of different colors is coated on the inner surface of each of these light-emitting tubes, and mercury and rare gas are filled in the discharge space, and a common discharge path is provided for each light-emitting tube. The present invention is characterized in that a single common electrode is provided, and the plurality of light emitting capillary tubes are arranged so that some of the openings are adjacent to each other, and the common electrode is provided close to and opposite to these openings.

[Embodiments of the invention]

The present invention will be described below with reference to drawings in which the present invention is applied to a large number of light sources arranged on a display screen.

Figure 1 shows a schematic diagram of a large display screen installed in a corner of a baseball stadium or stadium, for example. On a screen board 1 having a substantially rectangular shape, there are thousands to tens of thousands of light sources 2 and 3.
...are densely arranged. These light sources 2 are low-pressure mercury vapor discharge lamps typified by fluorescent lamps, and details thereof are shown in FIG. 2 and subsequent figures.

That is, 3 is an outer tube having a hollow cylindrical shape, and is made of a transparent material such as glass. One end of the outer tube 3 is integrally closed with a spherical part 4 having a substantially spherical shape, and the other end is left open. A light diffusion film (not shown) is attached. A disc-shaped glass stem 5 is hermetically sealed to the opening at the other end of the outer tube 3. Due to this sealing, there is a partition inside the outer tube 3 that is independent from the outside. A discharge space 6 is formed. In this discharge space 6, for example, three luminous thin tubes 7, 8 and 9 are housed. The luminous thin tubes 7, 8, and 9 of this embodiment are straight glass bulbs that are bent into a substantially U-shape from the middle, so that both ends are located adjacent to each other in the same direction. , the length from the U-shaped bent portion 10 to one end is longer than the length from the bent portion 10 to the other end, and the light emitting capillary is bent into a single-shape shape. 7,8.9
Each straight line portion is formed to have a length that exceeds at least the Faraday dark portion.

Moreover, three stem parts 20 that support the electrodes 11 are sealed on the stem 5 via lead wires 12 and 12,
One end of each light emitting capillary 7.8.9 is sealed to the sealed portion between the stem portion 20 and the stem 5.

By this sealing, the light emitting detail tube 7. 8. 9 is fixed on the stem 5 with the curved part 10 facing the spherical part 4 and the other end part 1G facing the stem 5 side, and with the openings 16 adjacent to each other. 7. 8. An electrode 11 is located at one end of the electrode 9 . For this reason, discharge paths 13, 14, 15 whose sides are approximately U-shaped are formed in the luminous tubes 7, 8.9, and these discharge paths 13, 14, 15 are located at the other end of each luminous tube 7, 8.9. It communicates with the inside of the discharge space 6 through the part 16, and the light emitting capillary 7. 8. The inner surface of 9 is coated with a phosphor that emits different monochromatic colors, for example, red, green, and blue in this example! , 7.18.19 are deposited.

On the other hand, luminescent tube 7. 8. On the stem 5 facing the other end opening 16 of the light emitting tube 7. 8. One common electrode 2 common to 9 discharge paths 13.14.15
1 are sealed via lead wires 23 and 23.

Further, a predetermined amount of gas mainly composed of mercury and a rare gas such as argon is sealed in the discharge space 6 through an exhaust pipe 22 led out from the stem 5, and after this filling, the exhaust pipe 22 is fused. sealed. The light sources 2 having such a configuration are closely arranged on the screen board 1 with the spherical portion 4 of the outer tube 3 facing the display side.

Therefore, each light emitting tube 7. 8. The light bulbs 11 and the common power source 21 of 9 are connected to a power source via a lighting device such as a ballast, and the light emitting tubes 7. 8. Discharge within the power supply 9 occurs between the power supply 11 sealed at one end thereof and the common power supply 2I. Note that although the discharge in this embodiment is performed by alternating current, it is of course possible to use direct current discharge. By controlling the lighting device with an image control unit such as a microcomputer, the number and position of the display elements 2 to emit light are changed according to the image signal, and various images are displayed on the screen board 1. It is now displayed.

Further, a switch (not shown) is provided in the circuit connecting each power source 11 and the lighting device, and by selectively opening and closing this switch, the light emitting capillary 7. 8. 9
changes, allowing a variety of luminescent colors to be obtained.

According to such a configuration, when a discharge occurs between the electrode 11 of each light emitting tube 7, 8.9 and the common electrode 12, the light emitting tube 7. 8. Ultraviolet light is emitted from the positive column passing through the discharge path +3.14.1.5 of 9, and this ultraviolet light passes through the light emitting tube 7. 8. 9 Inner surface phosphor coating 17° 18, 19
to excite the phosphor, and each light-emitting capillary 7, 8.
9 emits visible light of different colors. The visible light rays are then diffused by a diffusion film (not shown), and the respective colors are combined and radiated outward.

In this way, the light source 2 with the above configuration includes three light emitting tubes 7. 8. By selecting light source 9 to emit light, the color of the emitted light can be freely changed even though the light source 2 is a single light source. Therefore, compared to the conventional case of combining three light sources emitting monochromatic red, blue, and green light, the number of light sources used can be reduced to 1/3, and the entire device can be made more compact.

Further, the number of electrodes 11 and the number of lead wires 12 and 12 of the light source 2 can also be reduced by using the shared electrode 21.

Furthermore, in the present invention, the openings 16 of the light emitting tubes are placed next to each other, and the common electrodes are provided in close opposition to these openings 16. Loss in non-contributing parts can be reduced.

In addition, blue discharge light is generated by the discharge from the opening 16 to the common electrode, which causes color noise to the phosphor emission from the light emitting tube. Therefore, this color noise can be minimized as much as possible.

Furthermore, in this embodiment, monochromatic light emitting tubes of red, blue, and green were conventionally combined in order to produce any color, so in order for a person to see a mixture of these monochromatic colors, a person would have to look at it from a considerable distance. However, in this example, one light source 2
Since the color mixing phenomenon occurs within the screen, the image quality of the screen is significantly improved.

In the above-described embodiment, the shape of the light-emitting capillary is approximately U-shaped, but it may be shaped like a straight tube, for example, and the number of light-emitting tubes is not limited to three.

Further, the low pressure mercury vapor discharge lamp of the present invention has at least blue,
Since it has luminous tubes that emit light in green and red, you can not only control the switching of the luminous tubes that emit light, but also adjust the amount of light emitted to emit light in blue, green, and red.
By combining these colors, any color can be created, including white.

Furthermore, although the above embodiment is described as a display light source used for a display screen, the present invention is not limited to this.
For example, a single tube can be used as a light source for displaying effects that emit light in three colors: blue, green, and red.

〔Effect of the invention〕

According to the present invention described in detail above, a plurality of light emitting tubes each having an electrode at one end and an open end at the other end are housed in a discharge space formed within a light-transmitting outer tube, and The inner surface is coated with a phosphor film that emits light of different colors, and the discharge space is filled with mercury and gas, and a single common light-emitting tube is provided for the discharge path of each light-emitting tube. Since a common electrode is provided, light emission of various colors can be obtained even though it is a single tube. Therefore, the number of light sources used can be reduced, as well as the number of electrodes and lead wires. Furthermore, in the present invention, the opening I'' portions of each light-emitting capillary are placed adjacent to each other7, and the common electrode is placed close to and facing these openings, so energy loss that does not contribute to phosphor emission can be reduced, and color noise can be reduced. It can be suppressed.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention, FIG. 3 is a schematic configuration diagram of a display screen, FIG. 4 is an enlarged view of the part ■ in FIG.
2 is an exploded perspective view of the light source, FIG. 2 is a sectional view of the light source, and FIG. 5 is a sectional view taken along the V-V edge in FIG. 2. 3...Outer tube, 6...Discharge space. 7, 8. 9... Luminous tube, 11... Electrode. +3. 14. 15...Discharge path, 16...Opening. 1.7.18.19... Phosphor coating, 21...
・Shared electrode. Patent applicant Toshiba Lightic Co., Ltd. Agent Patent attorney Ono 1) Yoshihiro 2 Light source 3 Outer tube 1 ni = ;ko Figure 4

Claims (1)

[Claims] A discharge space that is airtightly partitioned and independent from the outside is formed within a translucent outer bulb, and a plurality of light emitting thin tubes each having an electrode at one end and an open end at the other end are housed within this discharge space. A phosphor film that emits light of different colors is coated on the inner surface of each of these light-emitting tubes, and mercury and rare gas are filled in the discharge space. A low-pressure mercury vapor discharge lamp provided with a single shared electric power source, characterized in that the openings of the plurality of light emitting tubes are adjacent to each other, and a common electrode is provided close to and opposite to these openings. Mercury vapor discharge lamp.