JPH08298100A - Discharge lamp device and lighting system - Google Patents

Abstract

PURPOSE: To reduce uneven illuminance with simple lamp constitution by arranging an aperture type discharge lamp in which a pair of belt-shaped windows to where a fluorescent material film is not applied is formed, a lamp holding device, and a reflecting body. CONSTITUTION: A fluorescent lamp L has constitution called an aperture type in a part, transparent, light transmitting windows (apertures) 5, 5 where a fluorescent film 4 is not formed are formed in the region about at 55 degrees right and left of the fluorescent film 4 in the central part. When the lamp L is lit, fluorescent films 3, 4 are excited by discharge within a glass tube bulb 1, and emit light. Part of light transmits the films 3, 4, is diffused, goes to the outside of the bulb 1, and is irradiated to a light diffusion plate D as direct light 91 or reflected light 92 reflected by a reflecting body R. Part of light is reflected by the films 3, 4, transmitted through belt-shaped parts 5, 5, goes to the outside of the bulb 1, and is irradiated to the plate D as direct light 93 or reflected light 92 reflected by the reflecting body R, and uneven illuminance in the diffusion plate D is reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a discharge lamp device used for general lighting, OA equipment such as personal computers and word processors, and display devices such as televisions and meters, and lighting for backlight devices equipped with the discharge lamp device. Regarding the device.

[0002]

2. Description of the Related Art In recent years, small personal computers, televisions, etc., or display devices for displaying characters and figures, which use a liquid crystal display device (hereinafter abbreviated as LCD), have been miniaturized and have high brightness. For example, a fluorescent lamp used in a backlight device for illuminating this LCD or a display device has a small input, and has a smaller diameter and a smaller power consumption than a fluorescent lamp for general general illumination, and at the same time, High luminance, high color rendering, and long life are desired.

There is a backlight device in which a discharge lamp such as a fluorescent lamp is arranged on the lower surface side of a light diffusing plate called a direct type. In the case of this discharge lamp device, the fluorescent lamp is combined with a reflector, and a plurality of straight tube lamps are used, or a U-shaped or W-shaped bent lamp having a large light emitting area is used.

[0004]

A fluorescent lamp in which a phosphor film having substantially the same thickness is formed on the entire inner surface of the tubular bulb is used, and the emitted light from the fluorescent lamp is directly or opposite to the light diffusing plate. The light emitted to the side is reflected by the reflection plate and directed toward the light diffusion plate.

However, in this discharge lamp device, the light intensity directly entering the light diffusing plate from the lamp is highest at a portion right above the lamp, and as the distance from the portion directly above the lamp increases, that is, the lamp. The light intensity decreases as the distance from the light source increases, and the reflected light from the reflection plate also comes to distant parts, but there is variation in the light intensity on the light incident side of the light diffusion plate. It is desired to further reduce the illuminance unevenness of the irradiation light.

On the other hand, various attempts have been made to make the illuminance distribution uniform by changing the shape of the reflector, but it was difficult to obtain a suitable one.

Of course, in the backlight device, the above light diffusing plate is used to obtain a uniform illuminance distribution on the irradiation surface, but the light itself incident on the light diffusing plate is also made uniform on the plate surface. In this case, the light emitted from the light diffusing plate can be made more uniform and the uneven illuminance can be reduced.

[0008] The present invention has been made in view of the above circumstances,
An object of the present invention is to provide a discharge lamp device that can reduce the occurrence of uneven illuminance with a simple lamp configuration, and an illumination device using this lamp device.

[0009]

In the discharge lamp device according to the first aspect of the present invention, a pair of fluorescent glass film is not coated on the surface of the straight tube glass tube bulb along the bulb axis. , An aperture-shaped discharge lamp having a strip-shaped window formed therein, a lamp holding device that supports the lamp so that the space between the pair of strip-shaped windows is directed toward the center in the light emission direction, and the light emission of the lamp. And a reflector provided on the opposite side to the direction.

In the discharge lamp device according to the second aspect of the present invention, the surface of the straight glass tube bulb is provided with a light diffusion film and a pair of strip-shaped window portions not coated with the light diffusion film along the bulb axis. The formed aperture-shaped discharge lamp, the lamp holding device that supports the lamp so that the space between the pair of strip-shaped windows is directed toward the center in the light emission direction, and a position opposite to the light emission direction of the lamp. It is characterized by including a reflector provided on the side.

In a discharge lamp device according to a third aspect of the present invention, a plurality of the above-mentioned aperture type discharge lamps are arranged in parallel,
Each lamp is equipped with a reflector.

In the discharge lamp device according to a fourth aspect of the present invention, the aperture-shaped discharge lamp has a discharge path portion formed by bending a glass tube, and a plurality of straight tubular discharge path portions are juxtaposed. In addition, each straight tubular discharge path portion is provided with a reflector.

In the discharge lamp device according to a fifth aspect of the present invention, the aperture-shaped discharge lamp comprising the bent glass tube bulb has a U-shape or a W-shape, and the discharge path portion has a straight tubular shape. The feature is that it is equipped with a reflector.

A discharge lamp device according to a sixth aspect of the present invention is characterized in that the reflector is integrally formed on the surface of the bulb.

A discharge lamp device according to a seventh aspect of the present invention is characterized in that the reflector is formed separately from the bulb.

An illumination device according to claim 8 of the present invention is the discharge lamp according to any one of claims 1 to 7, wherein the casing or the reflector and the main body or the reflector are disposed. It is characterized in that it is provided with a device and a lighting circuit device for this lamp. According to a ninth aspect of the present invention, there is provided an illumination device in which a housing or a reflector, a light control body provided to face the main body or the reflector, and the main body or the reflector and the light control body. The discharge lamp device according to any one of claims 1 to 7 and the lighting circuit device for the lamp.

An illumination device according to claim 10 of the present invention comprises:
The light control body is a light guide plate or a light diffusion plate.

[0018]

A phosphor film or a light diffusing film is formed in the central portion of the glass tube bulb of the lamp on the light emitting surface side, and a band-shaped window portion without a coating film is formed on both sides of the central portion where the coating film is formed. Since the light is emitted from the lamp, the intensity of the emitted light from the central portion of the lamp facing the irradiation direction is higher than that from the central portion of the lamp where the coating is not formed.

Therefore, the direct radiation light and the reflected light from the reflector are applied to the central portion of the illuminated surface closest to the lamp through the light diffusing film. Further, the irradiated surface far from the lamp away from the central portion of the irradiated surface is irradiated with strong radiation light from the band-shaped window and reflected light from the reflector.
Therefore, since the light intensity (amount) decreases in inverse proportion to the distance, the radiated light traveling toward the irradiated surface away from the central portion has a large decrease, but the amount of light reaching the irradiated surface is greater than that in the central portion. It is possible to obtain an illumination with little unevenness in illuminance over a wide range of the surface to be illuminated, which is not so different from the light amount.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 1 is a partially cutaway top view showing a discharge lamp device LD used in a backlight device or the like, and FIG. 2 is shown in FIG.
FIG. 3 is a side sectional view showing a section taken along line AA in FIG. 3, and FIG. 3 is an enlarged side sectional view showing a part of FIG. 2 in an enlarged manner.

In the figure, L is a fluorescent lamp, B is a rectangular box-shaped casing, a reflector R is mounted inside the casing B, and a light diffusion plate D is arranged on the upper portion. . Further, S is a lighting circuit device for lighting the fluorescent lamp L.

The bulb 1 of the fluorescent lamp L has three bent portions 11, 11, 11 formed by bending a straight glass tube made of soft glass such as soda-lime glass or lead glass back in the middle portion, for example, three times. 4 straight pipe parts 12,
It has a W-shape (also referred to as an M-shape) having 12, 12, and 12, and the discharge path is composed of one continuous path.
Then, rubber holders 2 are attached to sealing portions (not shown) at the ends of the straight pipe portions 12 on both outer sides, respectively.

Further, this fluorescent lamp L has a structure called an aperture shape as a part thereof, and as shown in an enlarged cross section of FIG. A three-wavelength type phosphor film 3 in which a phosphor having a red light emitting region is mixed is formed to a predetermined thickness, and a band-shaped phosphor of the same material and thickness as above is formed in a range of about 50 degrees in the central portion on the upper surface side. The film 4 is formed, and transparent light transmitting windows (apertures) 5 and 5 are formed in the central part of the phosphor film 4 in the range of about 55 degrees to the left and right of the phosphor film 4. Has been done. (A normal aperture lamp has one window.) Further, the bulb 1 is filled with an inert gas such as Ar (argon) and mercury, and the sealing portion has an electrode (not shown). It is sealed.

The reflector R is formed of a polycarbonate resin or a metal plate, has a W-shape (also called an M-shape) substantially the same as the bent shape of the lamp L, and has a concave shape along the bulb 1 axis. Recessed surface 6 in which reflective surface 7 is continuously formed
1 and a flat portion 62. When the reflector R itself has a high reflectance, the reflective surface 7 does not need to have a reflective layer.

The fluorescent lamp L having the above-mentioned apertures 5, 5 has a pair of band-shaped window portions (apertures).
5 and 5 are directed toward the center in the light emitting direction, and the reflector R is held on a holding device (not shown) at a position opposite to the light emitting direction of the lamp.

The light diffusing plate D is made of acrylic resin or the like and has a rectangular shape, and an uneven surface (not shown) is formed on the surface located on the lamp L side.
The light diffuser is mixed inside.

Further, the casing B has a rectangular box shape made of a polycarbonate resin or the like having an open upper surface,
The reflector R is mounted inside and a light diffusion plate D is placed on the side wall 81. A lighting circuit device S is provided on the bottom wall 81.

Then, in the discharge lamp device LD having the above-mentioned structure, when the fluorescent lamp L is lit through the lighting circuit device S,
The discharge in the bulb 1 excites the phosphor films 3, 4 to emit light. Then, a part of the light is transmitted through the phosphor films 3 and 4 and diffused to the outside of the bulb 1, and the direct light 9 is emitted to the light diffusion plate D.
, Or the reflected light 92 reflected by the reflector R is emitted. A part of the light is reflected by the phosphor films 3 and 4 and transmitted through the band-shaped windows 5 and 5 toward the outside of the bulb 1, and is reflected by the direct light 93, ... The reflected light 92 is emitted.

At this time, the light diffusing plate D directly above the central portion of the fluorescent lamp L is irradiated with the direct light 91, ... Through the phosphor film 4 and the reflected light 92 from the reflector R. Although the direct light 91 is diffused by the phosphor film 4, its light intensity (quantity) is average. In addition, the fluorescent lamp L
In the direction of the portion of the light diffusing plate D near the end of the recess 61 away from directly above the central portion, there is light emission of high light intensity (quantity) from the transparent strip-shaped window 5 in which the phosphor film is not formed. However, since the distance is long, the light intensity (amount) when reaching the light diffusion plate D is reduced, and a value that is not much different from the portion directly above the central portion of the fluorescent lamp L is obtained. That is, according to the configuration of the present invention, the light intensity (amount) of the central portion of the light diffusion plate D is not different from the conventional one, and the light intensity (amount) of the portion far from the central portion can be made higher than the conventional one. In addition, it was possible to reduce the difference in irradiation intensity between the central portion and the end portion and reduce the uneven illuminance on the light diffusion plate D.

The reflector R is molded from synthetic resin or a metal plate as described above, and a lighting circuit device S having a high-frequency lighting circuit for lighting the lamp L and an inverter circuit is provided on the back side thereof. Wiring such as a power supply line and a power supply line is attached. When the light is turned on, noise may be generated from the circuit device S or the wiring due to high frequency or electromagnetic action, and in the case of the reflector R made of a conductive material such as a metal plate, a flicker phenomenon occurs in the light emission of the discharge lamp L. As means for preventing the flicker phenomenon of light emission, a resin layer made of polycarbonate or the like having good light reflectivity is provided on the inner surface side of the reflector R, and a layer obtained by coating the surface of the polycarbonate with a thin film of aluminum is provided on the outer surface side. When the discharge lamp device using the formed reflector R is used as a backlight device of a liquid crystal display device, for example, a clear image can be obtained without flickering or shaking of the image, and also in terms of electrical characteristics. Increases safety.

FIG. 4 shows another embodiment of the discharge lamp device of the present invention. In the figure, the same parts as those in FIG. 3 are designated by the same reference numerals, and the description thereof will be omitted. In the embodiment of FIG. 4, the reflective layer 71 is directly formed on the surface of the bulb 1 of the fluorescent lamp L1, and the reflector is not particularly provided.

That is, the fluorescent lamp L shown in the above embodiment.
A reflective layer 71 is formed by sticking a light-reflecting substance such as aluminum in the form of a coating or tape so as to cover a range of about 200 degrees on the outer surface along the axis of the bulb. Even when such an aperture-type fluorescent lamp L1 is used, the same effects as those of the above-described embodiment can be obtained, and since it is not necessary to provide a reflector on the instrument side, the structure is simple and the device can be manufactured at low cost. Have advantages.

The present invention is not limited to the above embodiment. For example, the discharge lamp has been described as a fluorescent lamp in which mercury is enclosed in a glass tube bulb, but it may be a discharge lamp by rare gas emission in which mercury is not enclosed. In this case, a fluorescent substance film may be formed on the bulb. Even if the light diffusing film is formed by using an inorganic fine powder such as silica or titanium in place of the above-mentioned phosphor film, the same effect can be obtained.

Further, the phosphor film, the light diffusing film or the light reflecting film formed on the surface of the bulb of the lamp may be formed on either or both of at least one of the inner and outer surfaces, which is workability. It may be decided in consideration of economy.

The reflector is not limited to the one having the coating directly formed on the bulb, and a reflector made of metal or resin may be additionally provided on the outer surface of the bulb.

Further, the bulb shape of the lamp may be a tube shape having a straight tube portion, and a straight tube type lamp, W (M)
It can also be applied to discharge lamps that have bent portions such as letter-shaped, U-shaped, V-shaped, and L-shaped, or lamps that are straight tube-shaped bulbs connected by a thin tube into an H-shaped shape, and of course, the bent portion of the bulb. In, a window portion without a coating may be formed.

The number of lamps to be used may be one to a plurality of straight tube lamps arranged in parallel.

Further, the discharge electrode of the lamp is not limited to one provided in the bulb, but may have three or more electrodes such as an intermediate electrode, and the discharge electrode is not limited to the internal electrode and is provided on the outer surface of the bulb. It may be an external electrode.

The housing and the reflector are not essential, but the lamp holding device may be provided on the housing, the reflector, etc. as appropriate.

Further, the discharge lamp device is not limited to the one used for a backlight device for liquid crystal display, display, etc.
It can be applied to a lighting device used for general lighting, and the emitted light from the lamp is emitted as it is without any intervention, or the control of the light diffusion plate, the light guide, etc. as in the embodiment. It may be emitted via an optical body.

[0041]

As described above in detail, according to the present invention, a lamp device is constructed by using a discharge lamp having a novel aperture shape which is different from the conventional one, and in cooperation with the reflector, a wide range of light emission direction can be obtained. Light can be irradiated with a substantially uniform intensity (quantity).

Therefore, in the backlight device used for the liquid crystal display device and the illumination device used for general illumination, it is possible to improve the unevenness of illuminance and obtain a clear image or display or comfortable lighting.

[Brief description of drawings]

FIG. 1 is a partially cutaway top view showing an embodiment of a discharge lamp device of the present invention.

FIG. 2 is a side sectional view showing a section taken along line AA in FIG.

FIG. 3 is an enlarged side sectional view showing a part of FIG. 2 in an enlarged manner.

FIG. 4 is an enlarged side sectional view showing another embodiment of the discharge lamp device of the present invention.

[Explanation of symbols]

 LD: Discharge lamp device (illumination device) L, L1: Fluorescent lamp (discharge lamp) R: Reflector B: Housing D: Light diffusion plate (light control body) S: Lighting circuit device 1: Glass tube bulb 12: Direct Tubular parts 3, 4: Phosphor film (light diffusion film) 5: Window parts 91, 93: Direct light 92: Reflected light

Claims (10)

[Claims] 1. An aperture-shaped discharge lamp having a straight glass tube bulb having a fluorescent film and a pair of strip-shaped window portions not coated with the fluorescent film on the surface of the bulb. A lamp holding device that supports the lamp so that the band-shaped windows of the lamp are directed toward the center in the light emitting direction, and a reflector provided on the opposite side to the light emitting direction of the lamp. A discharge lamp device characterized by the above. 2. An aperture-type discharge lamp having a straight tube-shaped glass tube bulb having a surface on which a light-diffusing film and a pair of band-shaped windows not coated with the light-diffusing film are formed. A lamp holding device that supports the lamp so that the band-shaped windows of the lamp are directed toward the center in the light emitting direction, and a reflector provided on the opposite side to the light emitting direction of the lamp. A discharge lamp device characterized by the above. 3. The discharge lamp device according to claim 1, wherein a plurality of the aperture-type discharge lamps are arranged in parallel, and each lamp is provided with a reflector. 4. The aperture-shaped discharge lamp has a bent discharge path portion made of a glass tube, and a plurality of straight tubular discharge path portions are juxtaposed and each straight tubular discharge path portion is arranged. The discharge lamp device according to claim 1, wherein the discharge lamp device is provided with a reflector. 5. The aperture type discharge lamp comprising the bent glass tube bulb is U-shaped or W-shaped, and each straight tubular discharge path portion is provided with a reflector. The discharge lamp device according to claim 4. 6. The reflector according to claim 1, wherein the reflector is integrally formed on the surface of the bulb.
The discharge lamp device according to any one of 1. 7. The discharge lamp device according to claim 1, wherein the reflector is formed separately from the bulb. 8. A housing or a reflector, a discharge lamp device according to any one of claims 1 to 7 arranged on the main body or the reflector, and a lighting circuit device for the lamp. An illuminating device characterized by being provided. 9. The method according to claim 1, wherein the housing or the reflector, the light control body provided to face the main body or the reflector, and the light control body provided between the main body or the reflector and the light control body. An illumination device, comprising: the discharge lamp device according to claim 7; and a lighting circuit device for the lamp. 10. The lighting device according to claim 9, wherein the light control body is a light guide plate or a light diffusion plate.