KR20090052330A - Electric discharge lamp, illuminator, and liquid crystal display - Google Patents

Abstract

The cold cathode discharge lamp 1 of this invention is installed in the glass bulb 10, the electrodes 20 and 21 arrange | positioned inside the at least one edge part 12 and 13 of the said glass bulb, and the outer periphery of the said edge part. And metal conductors 30 and 31 electrically connected to the electrodes, and an emitter 40 disposed on an inner surface of the glass bulb. The end edge 30a of the metal conductor is located at the center side of the glass bulb than the end edge 20a of the electrode, and the emitter side is located at the center side of the glass bulb than the end edge 30a. Since the electric field strength at the position of the emitter at the start of the cold cathode discharge lamp is strong enough to induce ion bombardment, secondary electrons are easily generated and the dark starting characteristic is improved.

Conductor, electrode, emitter, end, glass bulb, center

Description

Discharge lamp, lighting device and liquid crystal display device {ELECTRIC DISCHARGE LAMP, ILLUMINATOR, AND LIQUID CRYSTAL DISPLAY}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a discharge lamp, a lighting device having the discharge lamp as a main light source, and a liquid crystal display device, and more particularly, to a discharge lamp provided with a metal conductor on an outer circumference of an end of a glass bulb where electrodes are disposed.

In the prior art, Japanese Patent Laid-Open No. 7-220622 discloses a cold cathode discharge lamp 2000 in which a cap-shaped metal sleeve 2002 is provided at an end of a glass bulb 2001, as shown in FIG. . The metal sleeve 2002 is electrically connected to the electrode 2004 disposed in the end of the glass bulb 2001 through the lead wire 2003. When the metal sleeve 2002 is inserted into the lamp holder of the lighting device, The cold cathode discharge lamp 2000 is fixed to the lighting device and can be connected to the lighting circuit of the lighting device. Therefore, soldering or the like is unnecessary at the time of mounting on the lighting device, and mounting is easier than the type without the metal sleeve 2002.

However, in the cold cathode discharge lamp 2000, when a negative voltage is applied to the electrode 2004 at start-up, an electric field between the electrode 2004 and the proximity conductor 2005 (for example, the bottom plate of the lighting device) is applied. As a result, the ions in the glass bulb 2001 are accelerated and collide with the electrode 2004 to generate secondary electrons. Then, discharge starts from the secondary electrons.

However, in the cold cathode discharge lamp 2000, the distance L4 between the metal sleeve 2002 and the proximity conductor 2005 is shorter than the distance L3 between the electrode 2004 and the proximity conductor 2005, and the electrode 2004 and the metal sleeve ( Since 2002 is at the same potential, a higher intensity electric field is generated between the metal sleeve 2002 and the proximity conductor 2005, resulting in a lower field strength between the electrode 2004 and the proximity conductor 2005. In this case, since the acceleration action of the electrons inside the glass bulb 2001 is weakened, the discharge is less likely to occur, and the dark starting characteristic deteriorates.

In particular, as shown by the dashed-dotted line 2006, the metal sleeve 2002 extends in the tube axis direction of the glass bulb 2001 to cover and cover the entire electrode 2004. Is hindered, the electric field strength between the electrode 2004 and the adjacent conductor is lowered, and the dark starting characteristic deteriorates as lighting is difficult.

This invention is made | formed in view of the said subject, and an object of this invention is to provide the discharge lamp which is excellent in dark starting characteristic, although the metal conductor is provided in the outer periphery of the edge part where the electrode is arrange | positioned. Another object of the present invention is to provide a lighting device and a liquid crystal display device having good dark startup characteristics.

In order to solve the said subject, the discharge lamp of this invention is a discharge lamp provided with the electrode arrange | positioned inside the at least one edge part of a glass bulb, and the metal conductor electrically connected to the said electrode in the outer periphery of the said end, The electric field strength is high enough to attract the ion bombardment at the start of the glass bulb, and is mounted between the proximity conductor and the electrode in a state where it is mounted on a lighting device provided with a proximity conductor electrically insulated from the lamp current path. It is characterized in that the emitter is installed.

Further, one embodiment of the discharge lamp of the present invention is characterized in that the emitter is provided on a track reaching the shortest distance from the proximity conductor to the electrode while avoiding the metal conductor between the proximity conductor and the electrode. do.

One embodiment of the discharge lamp of the present invention is characterized in that the emitter is made of a cesium compound.

Moreover, one form of the discharge lamp of this invention is characterized in that the said emitter is provided in the inner surface of the part in which the said metal conductor is not provided in the said glass bulb.

One embodiment of the discharge lamp of the present invention is characterized in that the metal conductor has a cylindrical shape having a slit or cutout portion, and the emitter is provided on an inner surface of a portion where the slit or cutout portion is located in the glass bulb.

One embodiment of the discharge lamp of the present invention is characterized in that an auxiliary emitter separate from the emitter is provided on the electrode.

Moreover, one form of the discharge lamp of this invention is characterized in that the end edge of the center side of the glass bulb of the metal conductor is located at the center side of the glass bulb rather than the end edge of the center side of the glass bulb of the electrode. do.

One embodiment of the discharge lamp of the present invention is characterized in that the emitter is made of a cesium compound.

Moreover, one form of the discharge lamp of this invention is characterized in that the said emitter is provided in the outer surface of the part in which the said metal conductor is not provided in the said electrode.

One embodiment of the discharge lamp of the present invention is characterized in that the metal conductor has a cylindrical shape having a slit or cutout portion, and the emitter is provided on an outer surface of a portion where the slit or cutout portion is located in the electrode.

One embodiment of the discharge lamp of the present invention is characterized in that the electrode is a cylindrical hollow electrode having a bottom surface, and the emitter is provided on an inner surface of the cylinder of the electrode.

The lighting apparatus of the present invention is characterized by including the discharge lamp.

The liquid crystal display device of the present invention is characterized by including the above lighting device.

According to the above structure, since the emitter is provided with a high electric field strength so as to attract the ion bombardment during startup in the glass bulb, ions in the glass bulb are accelerated by the electric field and easily collide with the emitter and the electrode. It is easy to obtain secondary electrons generated at the time of collision. Therefore, the discharge starting from the secondary electrons is easy to be initiated, and the dark starting characteristic is good even when the electric field generated between the electrode and the adjacent conductor is low due to the interference of the metal conductor.

1 is a cross-sectional view showing one end portion of a conventional cold cathode discharge lamp.

2 is a cross-sectional view showing a discharge lamp of the embodiment.

3 is a perspective view showing a sleeve.

4 is a view for explaining a mounting state of a cold cathode discharge lamp.

5 is a view for explaining the electric field strength between the electrode and the metal conductor.

6 is a cross-sectional view showing a discharge lamp used in the experiment.

7 is a diagram showing the effect of the sleeve on the dark starting characteristics.

8 is an enlarged cross-sectional view illustrating one end portion of a cold cathode discharge lamp of Modification Example 1;

9 is an enlarged cross-sectional view showing one end portion of a cold cathode discharge lamp of Modification Example 2. FIG.

10 is an enlarged cross-sectional view showing one end portion of the cold cathode discharge lamp of the third modification.

Fig. 11A is an enlarged plan view showing one end portion of the cold cathode discharge lamp of Modification 5, (b) is a sectional view taken along the line aa shown in (a), and (c) shows the sleeve of Modification 5; Perspective view.

12A is an enlarged plan view showing one end portion of a cold cathode discharge lamp of Modification 5, (b) is a cross sectional view taken along line bb of (a), and (c) shows a sleeve of Modification 5; Perspective view.

It is a perspective view which shows the modification of a sleeve.

14 is an enlarged cross-sectional view showing one end portion of the cold cathode discharge lamp of Modification Example 6;

FIG. 15 is an enlarged cross-sectional view showing one end portion of a cold cathode discharge lamp of Modification Example 7. FIG.

(A) is a front view which shows one end part of the cold cathode discharge lamp of the modification 8, (b) is a side view of the modification 8, (c) is an expanded sectional view of the part enclosed by the circle shown in (a). .

17 is a front view showing one end portion of a cold cathode discharge lamp of Modification Example 9;

18 (a) is a front view showing one end portion of the cold cathode discharge lamp of the modification 10, and (b) is a perspective view showing the sleeve of the modification 10;

19 is an enlarged cross-sectional view showing one end portion of the cold cathode discharge lamp of the modification 11.

20 is an enlarged cross-sectional view showing one end portion of the cold cathode discharge lamp of Variation 12;

FIG. 21 is an enlarged cross-sectional view showing one end portion of a cold cathode discharge lamp of Variation 13. FIG.

22 is an exploded perspective view showing the lighting apparatus of the first embodiment.

Fig. 23 is a partially cutaway perspective view of the lighting apparatus of the second embodiment.

24 is a schematic view showing a liquid crystal display device of the present embodiment.

(Explanation of the sign)

1, 100, 200, 300, 400, 500, 600, 700, 800, 850, 900, 1000, 1100, 1200 discharge lamp

10, 110, 210, 310, 410, 510, 610, 710, 810, 860, 910, 1010, 1110, 1210 glass bulb

12, 13, 112, 212, 312, 412, 512, 612, 712, 812, 862, 912, 1012, 1112, 1212 ends

20, 21, 120, 220, 320, 420, 520, 620, 720, 1020, 1120, 1220 electrodes

30, 31, 130, 230, 330, 430, 530, 550, 630, 730, 830, 880, 930, 1030, 1130, 1230 sleeve (metal conductor)

40, 140, 240, 340, 440, 540, 640, 740, 1040, 1140, 1240 emitter

51 Bottom Plate (Proximity Conductor)

50 lighting device

241 auxiliary emitter

430 slit

531 cutout

1300, 1400 Lighting

1500 LCD

[Discharge lamp]

<Configuration of Lamp>

Hereinafter, the discharge lamp of the embodiment of the present invention will be described with reference to the drawings.

2 is a cross-sectional view including the tube axis X of the discharge lamp of this embodiment. As shown in FIG. 2, the discharge lamp of the present embodiment is a cold cathode discharge lamp 1 used as a light source of a backlight unit, and includes a glass bulb 10, a pair of electrodes 20 and 21, and a pair of metals. Sleeves 30, 31 and emitter 40 as conductors.

The glass bulb 10 is formed by sealing both ends of a glass tube made of borosilicate glass (for example, SiO ₂ -B ₂ O ₃ -Al ₂ O ₃ -K ₂ O-TiO ₂ ). The glass tube is not limited to borosilicate glass, and may be lead glass, lead-free glass, soda glass, or the like. Lead glass, lead-free glass, and soda glass contain a large amount of alkali metal oxides such as sodium oxide (Na ₂ O), and these alkali metals are easily eluted to the inner surface of the glass bulb with the passage of time. The dark starting characteristic of the lamp 1 can be improved.

In particular, the glass bulb 10 preferably has an alkali metal oxide content of 3 [mol%] or more and 20 [mol%] or less. For example, when the alkali metal oxide is sodium oxide, the content thereof is preferably 5 [mol%] or more and 20 [mol%] or less. When it is 5 [mol%] or higher, the dark starting characteristic is improved, and when it exceeds 20 [mol%], the glass bulb 10 becomes black (dark brown) or white due to prolonged use to decrease luminance. Or a problem such as the strength of the glass bulb 10 is lowered.

In consideration of natural environment protection, it is preferable to use lead-free glass for the glass bulb 10. Lead-free glass herein refers to glass having a lead content of less than 0,1 [wt%]. In the case of lead-free glass, although lead is not actively added, the lead-free glass may contain some lead as an impurity in the manufacturing process, so it is specified as less than 0.1 [wt%].

The glass bulb 10 has a total length of 730 [mm], and includes a glass bulb body 11 and a pair of ends 12 and 13 positioned at both sides in the longitudinal direction of the glass bulb body 11.

The glass bulb body 11 is a tubular shape having a circular cross section, having an outer diameter of 4 [mm], an inner diameter of 3 [mm], and a thickness of 0.5 [mm]. The pair of ends 12, 13 are sealed at the sealing portions 14, 15, respectively, and the electrodes 20, 21 are disposed therein. The maximum width A in the tube axis X direction of the glass bulb 10 of the sealing portions 14 and 15 is 2 [mm]. Moreover, the sleeves 30 and 31 are provided in the outer periphery of each edge part 12 and 13, respectively.

In addition, the dimension of the glass bulb 10 is not limited to the above. However, in order to obtain the elongated cold cathode discharge lamp 1, the glass bulb 10 is preferably a small diameter and a thin film. Therefore, the glass bulb body 11 has an internal diameter of 1.4 [mm] to 7.0 [mm] and a thickness. It is preferable that they are 0.2 [mm]-0.6 [mm].

The phosphor layer 16 is formed on the inner surface of the glass bulb 10. Phosphor layer 16, for example, the blue phosphor is europium resurrection aluminate, barium-magnesium (europium-activated barium-magnesium aluminate ) [BaMg 2 Al 16 O 27: Eu 2 +] ( abbreviation: BAM-B), a green phosphor Hexavalent cerium-terbium-activated lanthanum phosphate [LaPO ₄ : Ce ³⁺ , Tb ³⁺ ] (abbreviation: LAP) and the red phosphor are europium-activated yttrium oxide [ It is formed of a rare earth phosphor composed of Y ₂ O ₃ : Eu ³⁺ ] (abbreviation: YOX).

In addition, the inside of the glass bulb 10 is, for example, about 1200 [μg] of mercury and rare gases, and a neon-argon mixed gas (Ne95 [%] + Ar 5 [%]) of about 8 [kPa] ([20 ° C.]). ]) Is enclosed. In addition, mercury and a rare gas are not limited to the above. For example, a neon-krypton mixed gas (Ne95 [%] + Kr 5 [%]) may be sealed as the rare gas. When the neon-krypton mixed gas is used as the rare gas, the starting characteristic of the lamp is improved, and the cold cathode discharge lamp 1 can be turned on at a low voltage.

The electrodes 20 and 21 are made of, for example, rod-shaped nickel (Ni), and are bonded to the lead wires 22 and 23 sealed in the sealing portions 14 and 15. The electrodes 20 and 21 are not limited to nickel, and may be, for example, niobium (Nb), tantalum (Ta), tungsten (W), or molybdenum (Mo). In addition, the shape of the electrodes 20 and 21 is not limited to a rod shape, A cylindrical shape with a bottom surface, a flat plate shape, etc. may be sufficient.

Each lead wire 22 and 23 is made of tungsten (W) inner lead wires 22a and 23a having the same thermal expansion coefficient as that of the glass bulb 10, and an external lead wire made of nickel that is easily attached to the solder. It is a joint line formed by joining (22b, 23b) by welding. Each lead wire 22, 23 extends linearly along the tube axis X direction of the glass bulb 10, and the joining surface of the inner lead wire 22a, 23a and the outer lead wire 22b, 23b is glass. It is approximately parallel with the outer surface of the bulb 10. That is, the inner lead wires 22a and 23a are located inward of the outer surface of the glass bulb 10, and the outer lead wires 22b and 23b are located outward of the outer surface of the glass bulb 10.

The internal lead wires 22a and 23a are substantially circular in cross section, having a total length of 3 [mm] and a wire diameter of 0.8 [mm]. End portions of the inner lead wires 22a and 23a are sealed to the sealing portions 14 and 15 of the glass bulb 10 at the ends of the outer lead wires 22b and 23b, and the outer lead wires 22b and 23b are separated from each other. The end of the opposite side is joined with the electrodes 20 and 21.

The outer lead wires 22b and 23b have a substantially circular cross section, have a total length B of 1 [mm] and a wire diameter of 0.6 [mm], and are arranged such that their axis cores substantially coincide with the tube axis X of the glass bulb 10. have. The outer lead wires 22b and 23b are entirely buried in the solder joints 32 and 33 in the sleeves 30 and 31, and the sleeves 30 and 31 are connected through the joints 32 and 33. ) Is electrically connected. The length C of the joint part 32, 33 of the tube axis X direction is 1.5 [mm].

On the inner lead wires 22a and 23a of the outer lead wires 22b and 23b, expansion portions 24 and 25 having a larger outer diameter than the outer lead wires 22b and 23b are in close contact with the end circumference of the glass bulb 10. It is preferable to be provided so that it may contact. That is, the inflation portions 24, 25 are located outside the outer surface of the glass bulb 10. When the expansion portions 24 and 25 are provided in this way, it is easy to adjust the dimensions from the expansion portions 24 and 25 to the electrodes 20 and 21, and the electrodes 20 and 21 and the glass bulb 10 are provided. The clearance gap D with the inner surface of can be kept small to about 0.5 [mm], and it is easy to adjust so that the effective light emission length E may become long.

In addition, the expansion portions 24 and 25 are formed of the same nickel material as the external lead wires 22b and 23b, but are not limited thereto. For example, the expansion portions 24 and 25 may be formed of a material such as an iron-nickel alloy or a copper-nickel alloy. It may be formed.

The lead wires 22 and 23 are not limited to the joint lines between the internal lead wires 22a and 23a and the external lead wires 22b and 23b, but may be one wire. For example, when the glass bulb is made of lead-free glass, the lead wires 22 and 23 are preferably an alloy of iron and nickel.

3 is a perspective view showing a sleeve. As shown in FIG. 3, the sleeve 30 (31) is a cylinder having a substantially C-shaped cross section and has slits 30 a (31 a), and the outside of the end portion 12 (13) of the glass bulb 10. It is attached to the outer periphery of the said edge part 12 (13) by inserting in the. As shown in FIG. 2, the sleeves 30 and 31 are 11 [mm] in length and 120 [micrometer] in thickness in the tube axis X direction, for example, and are an alloy of iron and nickel. In addition to the material of the sleeves 30 and 31, copper alloys such as phosphor bronze, brass and german silver may be used. In addition, the inner diameter of the sleeves 30 and 31 is designed to be slightly smaller than the outer diameter of the glass bulb 10, and there is a slight dimensional error between the inner diameter of the sleeves 30 and 31 and the outer diameter of the glass bulb 10. Even if it generate | occur | produces, the said dimension error is absorbed by the slit 30a, 31a, and the inner surface of the said sleeve 30 and 31 is in close contact with the outer surface of the said glass bulb 10. The sleeves 30 and 31 are electrically connected to the external lead wires 22b and 23b of the electrodes 20 and 21 via the solder joints 32 and 33.

In addition, the sleeves 30 and 31 are not limited to a cylinder having a substantially C-shaped cross section, and the slits 30a and 31a may be provided in a polygonal or elliptic cylinder having a substantially triangular cross section or a substantially square cross section. . Moreover, the case where the slit 30a, 31a is not provided is also conceivable. In addition, the sleeves 30 and 31 are not limited to an alloy made of iron and nickel, and may be made of at least a conductive material.

4 is a view for explaining a mounting state of a cold cathode discharge lamp. The cold cathode discharge lamp 1 is mounted to the lighting device 50, for example, as shown in FIG. A plurality of pairs of lamp holders 52 and 53 are arranged on the bottom plate 51 of the lighting device 50 at a position corresponding to the mounting position of each cold cathode discharge lamp 1. The lamp holders 52 and 53 are formed by bending a sheet made of copper alloy or aluminum, such as phosphor bronze, for example, and a pair of sandwich pieces 52a, 52b, 53a and 53b, and these The pinching pieces 52a, 52b, 53a, 53b are made of connecting pieces 52c, 53c for connecting at the lower edge.

The pair of sandwiching pieces 52a, 52b, 53a, 53b are provided with recesses adapted to the appearance of the cold cathode discharge lamp 1, and when the cold cathode discharge lamp 1 is inserted into the recesses, the sandwich pieces ( The cold cathode discharge lamp 1 is supported by the lamp holders 52, 53 by the leaf spring action of 52a, 52b, 53a, 53b, and at the same time, the lamp holders 52, 53 and the sleeves 30, 31 Is electrically connected. The cold cathode discharge lamp 1 mounted on the lighting device 50 is supplied with electric power through lamp holders 52 and 53 from a lighting circuit (not shown) of the lighting device 50.

Since the external lead wires 22b and 23b are accommodated in the sleeves 30 and 31 and the whole are buried in the joint portions 32 and 33, the cold cathode discharge lamp 1 is connected to the lighting device 50. When mounting, the external lead wires 22b and 23b hit and bend the lighting device 50, or the sealing portions 14 and 15 are broken by the stress applied to the external lead wires 22b and 23b when they are hit. There is little concern.

The cold cathode discharge lamp 1 of this embodiment is designed to have a longer length F in the tube axis X direction of the sleeves 30 and 31 than the conventional cold cathode discharge lamp. Thus, as shown in FIG. 2, the end edges 30a, 31a of the center side of the glass bulbs of the sleeves 30, 31 have the end edges 20a, 21a of the center side of the glass bulbs of the electrodes 20, 21. ), The distance G between the end edges 30a and 31a and the end edges 20a and 21a is 1.0 [mm] to 2.0 [mm].

4, the width H of the clamping pieces 52a, 52b, 53a, 53b of the lamp holders 52, 53 is also designed to be wide in accordance with the length F of the sleeves 30, 31. As shown in FIG. Such a configuration improves the attachability of the sleeves 30 and 31 to the lamp holders 52 and 53 and reduces the contact resistance between the sleeves 30 and 31 and the lamp holders 52 and 53.

Emitter 40 consists of cesium sulfate with a relatively small work function. By providing such cesium sulfate on the inner surface of the glass bulb 10, thermal electrons can be released into the discharge space by applying a slight amount of photo electrons and energy, and can be quickly shifted to start-up.

The emitter 40 is not limited to one consisting of cesium sulfate, but a cesium compound having a relatively small work function and having a low surface barrier required for electrons in the solid to escape out of the solid is suitable. As cesium compounds other than cesium sulfate, cesium molybdate, cesium aluminate, cesium niobate, cesium tungstate, cesium oxide, cesium hydroxide and the like can be used. Materials other than cesium compounds include alkaline earth metals (magnesium, calcium, strontium, barium), oxides of alkaline earth metals, alkali metals (lithium, sodium, potassium, cesium), oxides of alkali metals, and electron-radioactive materials (lanthanum, yttrium). And lanthanum barium, carbon) or those containing at least one of oxides of the electron-radioactive substance as main components.

The emitter 40 is provided in a cylindrical shape on the inner surface of one end 12 of the glass bulb 10. Specifically, it is provided in the position of the center side of a glass bulb rather than the edge 30a of the center side of the glass bulb of the sleeve 30, and the distance I between the said edge 30a and the emitter 40 is For example, it is 5 [mm]. This position is such that the field strength is high enough to attract ion bombardment at start-up. Since the emitter 40 is provided at such a position, secondary electrons are likely to be generated in the glass bulb 10 at startup. Accordingly, even when the weak discharge is easily started in the glass bulb 10, and the sleeves 30 and 31 are disturbed and the electric field strength generated in the glass bulb 10 is low, the dark starting characteristic is good.

In addition, the distance I between the end edge 30a and the emitter 40 is not limited to the above. Since the electric field is weakened away from the end edge 30a, it is preferable to arrange the emitter 40 at a position where the distance I having the strongest electric field becomes 0 [mm].

More specifically, the emitter 40 is provided such that the emitter 40 is positioned between the proximity conductor and the electrodes 20, 21 when the cold cathode discharge lamp 1 is mounted on the lighting device 5. have. Here, the proximity conductor is a conductor which is arranged to be close to the cold cathode discharge lamp 1 and is electrically insulated from the current path of the lamp and assists in starting. For example, the bottom plate 51 of the lighting device 50 corresponds to it.

The cold cathode discharge lamp 1 as described above operates at a lighting frequency of 40 [kHz] to 120 [kHz] and a lamp current of 3.5 [mA] to 8.5 [mA].

<Field Strength>

5 is a view for explaining the electric field strength between the electrode and the metal conductor. When the cold cathode discharge lamp 1 is mounted on the lighting device 50, as shown in FIG. 5, the sleeve 30 and the bottom plate (the distance from the distance L1 between the electrode 20 and the bottom plate 51 as the proximity conductors) The distance L2 of 51) becomes shorter. In addition, since the electrode 20 and the sleeve 30 are electrically connected, they have the same potential. Therefore, the electric field E ₁ generated between the electrode 20 and the bottom plate 51 is lower than the electric field E ₂ generated between the sleeve 30 and the bottom plate 51.

In particular, in the case of the cold cathode discharge lamp 1 of the present embodiment, as described above, the end edge 30a of the center side of the glass bulb of the sleeve 30 is the end of the center side of the glass bulb of the electrode 20. It is located at the center side of the glass bulb than the edge 20a, and the entire electrode 20 is accommodated in the sleeve 30. Accordingly, the electric field E ₁ on the track reaching the shortest distance from the base plate 51 to the electrode 20 while avoiding the sleeve 30 has a low electric field strength by a distance longer in order to avoid the sleeve 30.

In the conventional cold-cathode discharge lamp, since the emitter 4 is not installed at a position where the electric field strength is high enough to attract the ion shock at the start-up, secondary electrons are hardly generated in the glass bulb 10 at the start-up. In the low electric field strength, the weak discharge was difficult to start. However, in the cold cathode discharge lamp 1 of the present embodiment, the emitter 40 is provided on the track reaching the electrode 20 at the shortest distance from the base plate 51 while avoiding the sleeve 30. Since the electric field strength is high enough to attract the ion bombardment at the start-up, secondary electrons are easily generated in the glass bulb 10 during the start-up, and the starting characteristic under dark conditions is improved even in a low electric field strength.

<Dark start up characteristics>

As described above, the conventional cold cathode discharge lamp 2000 as shown in FIG. 1 has a poor dark start characteristic, and in particular, the electrode 2004 as the metal sleeve 2002 is indicated by the dashed-dotted line 2006. In the case where the whole is covered and covered, the dark starting characteristic is poor as lighting is difficult. Since this was confirmed by experiment, it demonstrates below.

6 is a cross-sectional view showing a conventional discharge lamp used for experiments of dark starting characteristics. 7 is a diagram showing the effect of the sleeve on the dark starting characteristics.

As shown in FIG. 6, the lamp 2100 used in the experiment is a cylindrical hollow electrode having a bottom surface of the electrodes 2120 and 2121, and an emitter 2140 is provided on an outer surface of the electrode 2120. Except for the point and the length in the tube axis X direction of the sleeves 2130 and 2131, respectively, they basically have the same configuration as the lamp 1 of the present embodiment. Therefore, the common constituent parts are denoted by the same two digits as the present embodiment and the description thereof is omitted.

The lamp 2100 used in the experiment has a total length of 617 [mm]. The glass bulb 2110 has an inner diameter of 2.4 [mm] and an outer diameter of 3.0 [mm], and is filled with a neon-argon mixed gas (Ne95 [%] + Ar 5 [%]) having a gas pressure of 60 Torr. The electrodes 2120 and 2121 are made of nickel and have a length of 5.5 [mm], an outer diameter of 2.1 [mm], and an inner diameter of 1.8 [mm] in the tube axis X direction. The internal lead wires 2122a and 2123a have a length of 3 [mm] in the tube axis X direction. The emitter 2140 has a length K in the tube axis X direction of 1.6 [mm], and the tube axis from the end edge on the center side of the glass bulb to the end edge 2120a on the center side of the glass bulb of the electrode 2120. The distance M in the X direction is 0.5 [mm].

As shown in FIG. 7, in the experiment, three types of lamps having different lengths in the tube axis X direction of the sleeves 2130 and 2131 were fabricated, and the influence of the sleeve on the dark starting characteristic was examined. When explaining the characteristics of each of the three lamps, the lamp 2100 having a length of 7.2 [mm] in the tube axis X direction of the sleeves 2130 and 2131 has an end edge at the center side of the glass bulb of the electrodes 2120 and 2121. 2120a and 2121a are located at the center side of the glass bulb of 2.0 [mm] than the end edge of the center side of the glass bulbs of the sleeves 2130 and 2131, and a part of the electrodes 2120 and 2121 is formed in the sleeve 2130, 2131 protrudes outward. The lamp 2100 having a length of 9.2 [mm] in the tube axis X direction of the sleeves 2130 and 2131 includes the end edges 2120a and 2121a and the sleeves 2130 and 2131 at the center side of the glass bulb of the electrodes 2120 and 2121. The end edges of the center side of the glass bulb () are at approximately the same position. Lamps 2100 having a length of 11.2 [mm] in the tube axis X direction of the sleeves 2130 and 2131 have end edges 2120a and 2121a at the center side of the glass bulbs of the sleeves 2130 and 2131. Is located on the center side of the glass bulb of 2.0 [mm] than the end edge of the center of the glass bulb, and the entirety of the electrodes 2120 and 2121 is accommodated in the sleeves 2130 and 2131.

After making three lamps 2100 for each type and leaving them in a dark room for 48 [h], measurement of the starting time t [ms] of each lamp 2100 under a constant temperature of 25 [° C] and each type An attempt was made to calculate the average starting time t [ms]. However, the lamps 2100 having a length of 11.2 [mm] in the tube axis X direction of the sleeves 2130 and 2131 did not turn on all three since the dark starting characteristics were remarkably bad. As can be seen from the result, the lamp in which the entire electrode is accommodated in the sleeve needs to be provided with an emitter at a position where the electric field strength is high enough to induce ion bombardment at start-up.

In addition, the emitter scatters due to ion bombardment during start-up, and fly ash and mercury react to form amalgam, and the amalgam causes the inner surface of the glass bulb to become black and lose the luminous flux of the lamp. In this case, the emitter is preferably installed near the sealing portion.

[Modification example]

The configuration of the cold cathode discharge lamp 1 of the present embodiment is not limited to the above configuration, and for example, it is conceivable to have the configuration as described in Modifications 1 to 7. In addition, the cold cathode discharge lamp of 13 in the modification 1 has the same structure as the cold cathode discharge lamp 1 of this embodiment fundamentally. Therefore, description of common parts is omitted and only other parts will be described in detail.

<Modification Example 1>

FIG. 8 is an enlarged cross-sectional view showing one end portion of the cold cathode discharge lamp of Modification Example 1. FIG. The cold cathode discharge lamp 100 shown in FIG. 8 is significantly different from the cold cathode discharge lamp 1 of the present embodiment in that the sleeve 130 is formed of a solder layer formed on the outer surface of the glass bulb 110. About the structure of another part, it is substantially the same as the said cold cathode discharge lamp 1. As shown in FIG.

The cold cathode discharge lamp 100 includes a glass bulb 110 having a phosphor layer 116 formed on an inner surface thereof, an electrode 120 disposed in an end 112 of the glass bulb 110, and an end portion 112 of the cold bulb discharge lamp 100. It is provided with the sleeve 130 and the emitter 140 provided in the outer periphery. The electrode 120 is electrically connected to the sleeve 130 through a lead wire 122 including an inner lead wire 122a and an outer lead wire 122b sealed to the sealing portion 114.

The sleeve 130 has a cap shape including a bonding portion 131 bonded to the outer lead wire 122b and a thin film portion 132 serving as a portion other than the bonding portion 131. It is provided on the outer surface of the said end part 112 so that 112 may be covered. The sleeve 130 is electrically connected to a lamp holder (not shown) that supports the end portion 112 of the cold cathode discharge lamp 100 when the cold cathode discharge lamp 100 is mounted on a lighting device (not shown). . Then, electric power is supplied from the lighting circuit of the lighting device through the lamp holder (not shown).

The junction portion 131 is a portion where the sleeve 130 is electrically connected to the lead wire 122. Since the joining portion 131 is substantially conical in appearance, the area of the outer surface is small despite completely covering the entire outer surface of the outer lead wire 122b. Therefore, since the area of the outer surface of the sleeve 130 is small and the heat dissipation action is small, the temperature of the lead wire 122 is hardly lowered.

In addition, since the outer lead wire 122b is completely covered by the sleeve 130, the outer lead wire 122b is bent or a stress is applied to the outer lead wire 122b so that the sealing portion 114 is broken. There is no concern.

The material for forming the sleeve 130 is not limited to solder, and may be a material having at least conductivity. However, it is preferable that the material has a low thermal conductivity so that the heat radiation action of the sleeve 130 is not large. In general, the solder is suitable for the material of the sleeve 130 because of its good conductivity, low thermal conductivity, and low price. In particular, the solder mainly composed of tin (Sn), tin-indium (In) alloy, tin-bismuth (Bi) alloy, or the like is more suitable because it can form a sleeve 130 having high mechanical strength. At least one of antimony (Sb), zinc (Zn), aluminum (Al), gold (Au), silver (Ag), copper (Cu), iron (Fe), platinum (Pt), and palladium (Pd). Since the added solder has good affinity with glass, it is possible to form a sleeve 130 that does not peel off well from the glass bulb 110, which is more suitable. Moreover, the solder which does not contain lead is suitable since it can manufacture the cold cathode discharge lamp 100 which considered environment.

When the material forming the sleeve 130 has good affinity with tungsten, it is also conceivable to make the outer lead wire 122b made of tungsten. In other words, it is conceivable to form the entire lead wire 122 in tungsten. By doing so, the disconnection defect of the lead wire 122 can be reduced and the cost of the component can be lowered.

The sleeve 130 can be formed by a known dipping method (for example, Japanese Patent Laid-Open No. 2004-146351). The method of forming the sleeve 130 by the dipping method will be briefly described. For example, the end 112 of the glass bulb 110 in which the electrode 120 is sealed is immersed in molten solder in the molten bath. do. When immersing the end part 112 in molten solder, you may add an ultrasonic wave. Since the dipping method can form the sleeve 130 simply and inexpensively, the cold cathode fluorescent lamp 100 can be manufactured at low cost.

In addition, the sleeve 130 may be formed by a method other than the dipping method. For example, you may form by methods, such as vapor deposition and plating.

It is conceivable that the outer surface of the sleeve 130 is covered with a conductive and low thermal conductivity material. For example, it is conceivable to cover the outer surface with a cylindrical member of tantalum agent. Thereby, peeling of a sleeve can be made difficult.

In addition, although the electrode 120 is rod-shaped, it is not limited to this, The bottom-shaped cylindrical shape or flat plate shape may be sufficient as it.

<Modification Example 2>

9 is an enlarged cross-sectional view showing one end portion of a cold cathode discharge lamp of Modification Example 2. FIG. The cold cathode discharge lamp 200 shown in FIG. 9 is significantly different from the cold cathode discharge lamp 1 of the present embodiment in that an auxiliary emitter 241 is provided on the outer surface of the electrode 220. The configuration of the part is almost the same as that of the cold cathode discharge lamp 1.

The cold cathode discharge lamp 200 includes a glass bulb 210 having a phosphor layer 216 formed therein, an electrode 220 disposed in an end portion 212 of the glass bulb 210, and an end portion 212 of the cold bulb discharge lamp 200. A sleeve 230 provided at an outer circumference, an emitter 240 having a configuration substantially the same as the emitter 40 of the present embodiment, and an auxiliary emitter 241 separate from the emitter 240 are provided. The electrode 220 is electrically connected to the sleeve 230 through the lead wire 222 and the junction portion 232 formed of the inner electrode 222a and the outer electrode 222b sealed in the sealing portion 214.

The auxiliary emitter 241 is provided on the outer circumference of the electrode 220 and is made of, for example, the same material as the emitter 240. The end edge 241a of the center side of the glass bulb of the auxiliary emitter 241 is provided near the sealing part 214. As shown in FIG. In the vicinity where the emitter 241 is provided, blackening occurs due to a large amount of cesium ions released by the ion bombardment at startup, so that the blackening does not affect the brightness of the cold cathode discharge lamp 200 as much as possible. It is preferable to provide the end edge 241a near the sealing portion 214 which is hard to affect.

Moreover, also in this modification, the electrode 220 is rod-shaped, It is not limited to this, The bottom-shaped cylindrical shape or flat plate shape may be sufficient as it.

<Modification Example 3>

10 is an enlarged cross-sectional view showing one end portion of the cold cathode discharge lamp of the third modification. The cold cathode discharge lamp 300 shown in FIG. 10 is a cylindrical hollow electrode having a bottom surface of the electrode 320, and the emitter 340 is provided on the inner surface of the tube of the electrode 320. There is a great difference from the cold cathode discharge lamp 1 of the embodiment, and the configuration of other parts is almost the same as the cold cathode discharge lamp 1.

The cold cathode discharge lamp 300 includes a glass bulb 310 having a phosphor layer 316 formed therein, a cylindrical electrode 320 having a bottom surface disposed in an end portion 312 of the glass bulb 310, A sleeve 330 is provided on the outer circumference of the end portion 312 and an emitter 340 is provided on the inner surface of the tube of the electrode 320. The electrode 320 is electrically connected to the sleeve 330 through a lead wire 322 and a junction portion 332 including an inner electrode 322a and an outer electrode 322b sealed to the sealing portion 314.

The electrode 320 is made of nickel (Ni), and has a total length of 5.2 [mm], an outer diameter of 2.7 [mm], an inner diameter of 2.3 [mm], and a thickness of 0.2 [mm]. The electrode 320 is not limited to nickel, and for example, niobium (Nb), tantalum (Ta), molybdenum (Mo), or tungsten (W) may be considered.

The electrode 320 is disposed so that the tube axis of the tube portion and the tube axis of the glass bulb 310 approximately coincide with each other. It is almost uniform. The space | interval of the outer peripheral surface of a cylinder part and the inner surface of the glass bulb 310 is 0.15 [mm] specifically. Since the interval is narrowed in this manner, discharge does not enter the interval, and discharge occurs only inside the electrode 320. Therefore, the sputtering material scattered by the discharge does not adhere well to the inner surface of the glass bulb 310, and the life of the cold cathode discharge lamp 300 is long. As described above, by using the electrode 320 alone, sputtering from the electrode to the inner surface of the glass bulb can be reduced, and mercury consumption can be reduced.

In addition, since the discharge is difficult to return to the lead wire 322 side, the lead wire 322 is hardly heated by the discharge, so that the life of the cold cathode discharge lamp 300 can be extended.

The interval between the outer circumferential surface of the tube portion of the electrode 320 and the inner surface of the glass bulb 310 is not necessarily 0.15 [mm], but the interval is preferably 0.2 [mm] or less in order to prevent discharge. .

The emitter 340 is provided over the entire inner surface of the tube of the electrode 320 using the same material as the emitter 40 of the present embodiment. In addition, the emitter 340 does not necessarily need to be provided over the entire inner surface of the cylinder, and may be provided on a part of the inner surface. Since the emitter 340 is provided on the inner surface of the cylinder of the electrode 320, blackening of the inner surface of the glass bulb 310 by cesium ion does not occur easily.

<Modification example 4>

FIG. 11A is an enlarged plan view showing one end portion of the cold cathode discharge lamp of Modification 4, FIG. 11B is a cross-sectional view taken along the line aa shown in FIG. 11A, and FIG. A perspective view of a sleeve.

11A and 11B, the cold cathode discharge lamp 400 includes a slit 431 formed in the sleeve 430 to improve the electric field strength between the electrode 420 and the adjacent conductor (not shown). It differs greatly from the cold cathode discharge lamp 1 of this embodiment in that it is, and the structure of another part is substantially the same as the said cold cathode discharge lamp 1.

The cold cathode discharge lamp 400 includes a glass bulb 410 having a phosphor layer 416 formed on an inner surface thereof, an electrode 420 disposed in an end portion 412 of the glass bulb 410, and a portion of the end portion 412. It has a sleeve 430 provided on the outer circumference, and an emitter 440 provided on the inner surface of the glass bulb 410. The electrode 420 is electrically connected to the sleeve 430 through the lead wire 422 and the junction portion 432 formed of the internal electrode 422a and the external electrode 422b.

As shown in FIGS. 11A and 11B, the emitter 440 is slightly wider than the slit 431 in the radial direction of the glass bulb 410 and is provided at a position opposite to the slit 431. have. As such, by providing the emitter 440 only in a region having a high electric field strength, unnecessary consumption of the emitter 440 material can be suppressed. In addition, in order to easily manufacture the cold cathode discharge lamp 400, the emitter 440 may be provided in a cylindrical shape over the entire circumference of the glass bulb 410 in the radial direction. In addition, the emitter 440 may be provided on the outer surface of the electrode 420 in a cylindrical shape in accordance with the position of the slit 431.

Also, in the present modification, the shape of the electrode 420 is not limited to a rod shape, and may be a bottomed cylindrical shape or a flat plate shape. However, the outer surface of the bottomed cylindrical shape has an outer surface of the electrode 420. Say the surface.

The sleeve 430 is a substantially C-shaped cylinder having a slit 431, and is mounted on the outer circumference of the end portion 412 so as to be inserted from the outside into the end portion 412 of the glass bulb 410. Unlike the slit 30a of the present embodiment, the slit 431 also has a function for improving the electric field strength between the electrode 420 and the proximity conductor (not shown). That is, the slit 431 of the modified example 4, firstly, similarly to the slit 30a of this embodiment, even if some dimensional error occurs between the inner diameter of the sleeve 430 and the outer diameter of the glass bulb 410, the sleeve. An inner surface of the 430 has a function to closely contact the outer surface of the glass bulb. Second, by forming a portion in which the sleeve 430 is not provided on the outer circumference of the glass bulb 410, that is, a portion without the sleeve 430 interposed between the electrode 420 and the proximity conductor, It has a function to increase the electric field strength between the electrode 420 and the adjacent conductor sandwiched between.

Since the slit 431 is wider than the slit 30a of this embodiment, the slit width J shown in FIG. 11 (c) is about 1/6 of the outer circumference of the glass bulb 410, for example, an outer diameter of 4 [mm]. ] (Inner diameter 3 [mm]), it is about 2 [mm]. In addition, the slit width J is not limited to the above, but in order to sufficiently increase the electric field strength, the slit width J must be somewhat wide, and at least 1/3 of the outer circumference of the glass bulb 410, for example, an outer diameter of 4 [mm] (inner diameter). In the case of the glass bulb 410 of 3 [mm], it is preferable that it is 4 [mm] or more.

The emitter 440 is provided on the inner surface of the portion of the glass bulb 410 where the sleeve 430 is not provided on the outer circumference, that is, on the inner surface of the portion where the slit 431 is located on the outer circumference. As such, when the emitter 440 is provided at a position where the electric field strength is high, secondary electrons are easily generated in the glass bulb 410 at startup.

In addition, the emitter 440 is not limited to the case where it is provided in the inner surface of one part area | region in the part in which the slit 431 is located in the outer periphery, as shown to FIG. 11 (a) and (b). It may be provided in the inner surface of all the regions in the part where the slit 431 is located in the outer periphery. Moreover, a part of the emitter 440 may be provided in the inner surface of parts other than the part in which the slit 431 is located in the outer periphery.

In addition, the sleeve 430 is not limited to a substantially C-shaped cylinder in cross section, and the slits 431 may be provided in a polygonal or elliptic cylinder in a substantially triangular cross section or a substantially square cross section. In addition, the shape of the slit 431 is not limited to the linear shape as shown in FIG. 11, It is curved and may be curved shape.

<Modification example 5>

12A is an enlarged plan view showing one end portion of the cold cathode discharge lamp of Modification 5, FIG. 12B is a cross-sectional view taken along line bb of FIG. 12A, and FIG. 12C is a modification 5 A perspective view of a sleeve.

12A and 12B, the cold cathode discharge lamp 500 includes a cutout 531 formed in the sleeve 530 to improve the electric field strength between the electrode 520 and the adjacent conductor (not shown). It differs greatly from the cold cathode discharge lamp 1 of this embodiment in that it is substantially the same as the cold cathode discharge lamp 1 with respect to the configuration of the other parts.

The cold cathode discharge lamp 500 includes a glass bulb 510 having a phosphor layer 516 formed on an inner surface thereof, an electrode 520 disposed in an end portion 512 of the glass bulb 510, and a portion of the end portion 512. Sleeve 530 is provided on the outer periphery, and the emitter 540 is provided on the inner surface of the glass bulb 510. The electrode 520 is electrically connected to the sleeve 530 through the lead wire 522 and the junction part (not shown).

The sleeve 530 is a cylindrical body having a circular cross section and has a cutout portion 531, and is mounted on the outer circumference of the end portion 512 so as to be externally inserted into the end portion 512 of the glass bulb 510.

The cutout 531 has a function for improving the electric field strength between the electrode 520 and the proximity conductor (not shown). The cutout portion 531 has a length in the tube axis direction of the glass bulb 510 of 5 [mm] and a length in the radial direction of 2 [mm], for example.

By providing the cutout 531, a portion where the sleeve 530 is not provided on the outer circumference of the glass bulb 510, that is, a portion where the sleeve 530 is not interposed between the electrode 520 and the proximity conductor. The distance between the electrode 520 and the proximity conductor in the glass bulb 510 is shortened to increase the electric field strength between the electrode 520 and the proximity conductor with the portion interposed therebetween. In order to sufficiently increase the electric field strength, the opening area of the cutout portion 531 is preferably 10 [mm 2] or more.

It is a perspective view which shows the modification of a sleeve. As shown in FIG. 13, the cutout portion 551 of the sleeve 550 can increase the opening area by widening the width in the radial direction of the glass bulb 510. In addition, by providing the slit 552 separately from the cutout 551, the glass bulb 510 can be easily mounted.

The emitter 540 is provided on the inner surface of the glass bulb 510 in which the sleeve 530 is not provided on the outer circumference, that is, on the inner surface of the portion where the cutout 531 is located on the outer circumference. In this way, when the emitter 540 is installed at a high electric field strength, secondary electrons are easily generated in the glass bulb 510 at startup.

In addition, the emitter 540 is not limited to the case where it is provided in the inner surface of one part area | region in the part in which the cutout part 531 is located in the outer periphery, as shown to FIG. 12 (a) and (b). It may be provided in the inner surface of every area | region in the part in which the cutout part 531 is located in the outer periphery. Moreover, a part of the emitter 540 may be provided in the inner surface of parts other than the part in which the cutout part 531 is located in the outer periphery, for example, cylindrical shape over the whole perimeter of the radial direction of the glass bulb 510, for example. May be installed. In addition, the emitter 540 may be provided, for example, in a cylindrical shape in accordance with the position of the cutout 531 on the outer surface of the electrode 520.

Also, in the present modified example, the shape of the electrode 520 is not limited to a rod shape, and a bottomed cylindrical or flat plate may be used. Say the surface.

The sleeve 530 is not limited to a cylinder having a circular cross section, and the cutout portion 531 may be provided in a polygon such as an approximately triangular or approximately square cross section or an elliptic cylinder. The shape of the cutout 531 is not limited to the quadrangle as shown in FIG. 12, and may be a polygon, a circle, an ellipse, or the like other than the quadrangle.

<Modification Example 6>

14 is an enlarged cross-sectional view showing one end portion of the cold cathode discharge lamp of Modification Example 6; In the cold cathode discharge lamp 600 shown in FIG. 14, the end edge 620a of the center side of the glass bulb of the electrode 620 is larger than the end edge 630a of the center side of the glass bulb of the sleeve 630. Located in the center of the bulb, the emitter 640 is significantly different from the cold cathode discharge lamp 1 of the present embodiment in that it is installed at a position in consideration of its positional relationship, and for the configuration of the other parts the cold cathode It is almost the same as the discharge lamp 1.

The cold cathode discharge lamp 600 includes a glass bulb 610 having a phosphor layer 616 formed on an inner surface thereof, an electrode 620 disposed in an end 612 of the glass bulb 610, and a portion of the end portion 612. A sleeve 630 provided on an outer circumference and an emitter 640 provided on an inner surface of the glass bulb 610 are provided. The electrode 620 is electrically connected to the sleeve 630 through the lead wire 622 and the junction 632 which are formed of the inner lead wire 622a and the outer lead wire 622b sealed to the sealing portion 614. have.

The emitter 640 is a sealing portion 614 side of the end portion 620a of the center side of the glass bulb of the electrode 620 on the inner surface of the glass bulb 610, and is the center side of the glass bulb of the sleeve 630. Is provided at the position closer to the center of the glass bulb than the end edge 630a of the glass bulb.

The sealing portion 614 side is farther from the main light emitting area of the lamp than the end edge 620a of the center side of the glass bulb of the electrode 620. Therefore, even if the emitter 640 is installed here, the emitter 640 scatters due to the ion bombardment at the start-up, and the fly ash and mercury react to form an amalgam, and the amalgam creates an inner surface of the glass bulb 610. This blackening hardly causes a problem that the luminous flux of the lamp is lost.

On the other hand, since the electric field strength between the electrode 620 and the proximity conductor (not shown) is higher than the end edge 630a of the center side of the glass bulb of the sleeve 630, the emitter 640 here. The secondary electrons are easily generated in the glass bulb 610 at startup.

Moreover, it is preferable that the length in the tube axis direction of the glass bulb 610 of the sleeve 630 is 19 [mm] or less depending on the thickness of the sleeve 630. Further, since the glass bulb center portion becomes the main light emitting area of the lamp than the end edge 620a of the glass bulb center portion side of the electrode 620, the length of the sleeve 630 is taken into consideration when the loss of luminous flux caused by the sleeve 630 is taken into consideration. It is more preferable that it is 10 [mm] or less. Moreover, in order to suppress the heat radiation from the sleeve 630 to be small, it is preferable to make the said sleeve 630 as small as possible, and it is preferable that the said length of the said sleeve 630 is 19 [mm] or less.

Moreover, also in this modification, the electrode 620 is rod-shaped, It is not limited to this, The bottom-shaped cylindrical shape or flat plate shape may be sufficient as it.

<Modification Example 7>

FIG. 15 is an enlarged cross-sectional view showing one end portion of a cold cathode discharge lamp of Modification Example 7. FIG. In the cold cathode discharge lamp 700 shown in FIG. 15, the end edge 720a of the center side of the glass bulb of the electrode 720 is larger than the end edge 730a of the center side of the glass bulb of the sleeve 730. Located in the center of the bulb, the emitter 740 is significantly different from the cold cathode discharge lamp 1 of the present embodiment in that it is installed at a position in consideration of its positional relationship, the cold cathode for the configuration of other parts It is almost the same as the discharge lamp 1.

The cold cathode discharge lamp 700 includes a glass bulb 710 having a phosphor layer 716 formed therein, an electrode 720 disposed in an end portion 712 of the glass bulb 710, and an end portion 712 of the cold bulb discharge lamp 700. A sleeve 730 provided on an outer circumference and an emitter 740 provided on an outer circumference of the electrode 720 are provided. The electrode 720 is electrically connected to the sleeve 730 through the lead wire 722 and the junction portion 732 formed of the inner electrode 722a and the outer electrode 722b sealed in the sealing portion 714.

The emitter 740 is provided at the position of the center side of the glass bulb rather than the end edge 730a of the center side of the glass bulb of the sleeve 730 on the outer surface of the electrode 720. Since the electric field strength between the electrode 720 and the proximity conductor (not shown) is higher than the end edge 730a of the center side of the glass bulb of the sleeve 730, the emitter 740 is provided here. Lower electrons tend to be generated in the glass bulb 710 at startup.

In addition, the emitter 740 scatters due to the ion bombardment at the start-up, and the fly ash and mercury react to form amalgam, and the inner bulb of the glass bulb 710 is blackened by the amalgam, so that the luminous flux of the lamp is lost. In order to make the problem less likely to occur, it is preferable to install the emitter 740 on the sealing part 714 side.

The length in the tube axis direction of the glass bulb 710 of the sleeve 730 is 7.5 [mm], for example. The length of the sleeve 730 is preferably 19 [mm] or less depending on the thickness of the sleeve 730. Further, since the glass bulb center portion becomes the main light emitting area of the lamp than the end edge 720a of the glass bulb center portion side of the electrode 720, the length of the sleeve 730 is taken into consideration when the loss of luminous flux caused by the sleeve 730 is taken into consideration. It is more preferable that it is 10 [mm] or less. Moreover, in order to suppress the heat radiation from the sleeve 730 small, it is preferable to make the said sleeve 730 as small as possible, and it is preferable that the said length of the said sleeve 730 is 19 [mm] or less.

Moreover, also in this modification, the electrode 720 is rod-shaped, It is not limited to this, The bottom-shaped cylindrical shape or flat plate shape may be sufficient as it.

<Modification Example 8>

 (A) is a front view which shows one end part of the cold cathode discharge lamp of the modification 8, FIG. 16 (b) is a side view of the modification 8, and FIG. 16 (c) is a circle | round | yen shown in (a). An enlarged cross-sectional view of the surrounding portion.

The cold cathode discharge lamp 800 shown in FIGS. 16 (a) and 16 (b) is greatly different from the cold cathode discharge lamp 1 of this embodiment in that a metal mesh is used for the sleeve 830. The configuration of the part is almost the same as that of the cold cathode discharge lamp 1. Therefore, only the above difference will be described, and descriptions of other configurations will be omitted.

The cold cathode discharge lamp 800 includes a glass bulb 810, an electrode (not shown) disposed inside at least one end portion 812 of the glass bulb 810, and an outer circumference of the end portion 812. A sleeve 830 as a metal conductor electrically connected through an electrode and a lead wire 822 is provided.

The sleeve 830 is composed of a main body portion 831, a clamping portion 823, and a conductive portion 833, and the cold cathode discharge lamp (not shown) when the cold cathode discharge lamp 800 is mounted on a lighting device (not shown). It is electrically connected to a lamp holder (not shown) that supports the end 812 of 800.

The main body 831 is a cap-shaped member covering the outer circumference of the end 812 and is made of a metal mesh. It is preferable that the mesh of the main body portion 831 has a wire diameter of 5 [µm] to 120 [µm] and a mesh size of 0.1 [mm] to 3 [mm]. In addition, the body portion 831 is preferably made of a metal such as an iron-nickel alloy in order to obtain good conductivity.

The clamping portion 832 is a C-shaped cylinder whose surface is fixed to the inner side of the opening of the main body portion 831 by clamping the glass bulb 810 so as to sandwich the main body portion 831 to the glass bulb 810. It plays a role of fixing. The inner diameter of the clamping portion 832 is designed to be slightly smaller than the outer diameter of the end portion 812. When the sleeve 830 is attached to the end portion 812, the clamping portion 832 is internally disposed at the end portion 812. The end portion 812 is pushed into the main body portion 831 by pressing to widen. Since the clamping part 832 tightens the edge part 812 from the outside by the force which tries to return to original shape, the main-body part 831 is fixed to the glass bulb 810 by the force.

The conductive portion 833 is provided on the side opposite to the opening side of the main body portion 831 so as to contact both the main body portion 831 and the lead wire 822, and the main body portion 831 It serves to electrically connect the lead wires 822. In addition, the main body 831 serves as a stopper for preventing the end portion 812 from being pulled out.

As shown in Fig. 16C, the conductive portion 833 has a disk shape having a recess 833a for inserting the external lead wire 822b of the lead wire 822 at the center thereof. The concave portion 833a is shaped to cause the main body side to be largely hardened toward the main body side, and the external lead wires 822b and the internal lead wires are formed on the protruding portions. The welded portion 822c with 822a is housed.

The conductive portion 833 is made of conductive rubber. When the sleeve temperature reaches about 140 [deg.] C., the conductive portion 833 is melted to insulate the main body portion 831 and the lead wire 822 from each other. Therefore, even if the sleeve 830 becomes high temperature by overcurrent, it can prevent that resin members, such as an optical sheet, deform | transform by the heat, for example, when mounted in the illuminating device like a backlight unit. Moreover, the electrode which interposed the said part was formed by forming the part in which the sleeve 830 is not provided in the outer periphery of the glass bulb 810, ie, the part in which the sleeve 830 is not interposed between an electrode and a proximity conductor. It has a function to increase the electric field strength between and the proximity conductor.

<Modification Example 9>

17 is a front view showing one end portion of a cold cathode discharge lamp of Modification Example 9; The cold cathode discharge lamp 850 shown in FIG. 17 differs greatly from the cold cathode discharge lamp 1 of the present embodiment in that the sleeve 880 has a coil shape, but the configuration of the other parts is different from the cold cathode discharge lamp. It is almost the same as (1). Therefore, only the above difference will be described, and description of other configurations will be omitted.

The cold cathode discharge lamp 850 includes a glass bulb 860, an electrode (not shown) disposed inside at least one end 862 of the glass bulb 860, and an outer circumference of the end 862. A sleeve 880 as a metal conductor electrically connected via an electrode and a lead wire 872 is provided.

The sleeve 880 is formed by bending one metal wire in a coil shape, and the main body portion 881 wound along the outer circumference of the end portion 862 of the glass bulb 860 and the connection portion 882 wound on the lead wire 872. Has The metal wire has a diameter of 5 [μm] to 120 [μm] before being attached to the end 862 of the glass bulb 860, and the main body portion 881 has a mandrel diameter of 0.8 [mm] to 3.8 [mm], The pitch length is 0.1 [mm]-3 [mm], the connection part 882 has a mandrel diameter of 0.3 [mm]-0.7 [mm], and the pitch length is 0 [mm].

The sleeve 880 has a coil shape and a portion where the sleeve 880 is not provided on the outer circumference of the glass bulb 860, that is, a portion where the sleeve 880 is not interposed between the electrode and the proximity conductor. This has a function of increasing the electric field strength between the electrode sandwiched between the portion and the proximity conductor. In addition, in order to obtain good dark start characteristic, it is preferable that the pitch of the coil of the main-body part 881 is the said range. Moreover, in order to acquire favorable electroconductivity, it is preferable that the main-body part 881 consists of metal wires, such as iron-nickel alloy.

Since the mandrel diameter of the body portion 881 is designed to be slightly smaller than the outer diameter of the glass bulb 860, and the mandrel diameter of the connection portion 882 is designed to be slightly smaller than the outer diameter of the lead wire 872, the body portion ( The sleeve 880 is fixed to the glass bulb 860 by a force of 881 to fasten the glass bulb 860 and a force of the connection part 882 to fasten the lead wire 872. In addition, in order to fix the sleeve 880 to the glass bulb 860 more firmly, the lead wire 872 and the connecting portion 882 may be welded or adhered with a conductive adhesive.

<Modification Example 10>

18 (a) is a front view showing one end portion of the cold cathode discharge lamp of the modification 10, and (b) is a perspective view showing the sleeve of the modification 10; The cold cathode discharge lamp 900 shown in FIGS. 18A and 18B has a configuration in which the sleeve 930 is significantly different from the cold cathode discharge lamp 1 of the present embodiment. It is almost the same as the negative electrode discharge lamp 1. Therefore, only the above difference will be described, and description of other configurations will be omitted.

The cold cathode discharge lamp 900 includes a glass bulb 910, electrodes (not shown) disposed inside at least one end portion 912 of the glass bulb 910, and an outer periphery of the end portion 912. The cylindrical sleeve 930 as a metal conductor electrically connected through the said electrode and the lead wire 922 is provided.

The sleeve 930 is punched into a substantially U-shape at one location on the outer circumferential surface, and the punched portion is a slit portion 931 for drawing light into the end portion 912 of the glass bulb 910. The left side of the punched-out side of the slit portion 931 is a clip portion 932 for fixing the sleeve 930 to the glass bulb 910. The cold cathode discharge lamp 900 has a slit portion 931 in the sleeve 930, that is, a portion in which the sleeve 930 is not interposed between the electrode and the adjacent conductor. It has the function of increasing the electric field strength between adjacent conductors. In addition, the substantially U-shaped punching part is not limited to one place but may be provided in several places.

Restricting pieces 933a to 933e are provided at the end edges of the sleeve 930 on the lead wire side. When the sleeve 930 is attached to the glass bulb 910, a glass bulb (933a to 933e) is attached to the restricting pieces 933a to 933e. Sleeve 930 is positioned such that end 912 of 930 is in contact.

In addition, the sleeve 930 has a conductive portion 934 for electrically connecting the sleeve 930 and the lead wire 922 at an end edge of the lead wire 922 side. The electroconductive part 934 is a bimetallic long plate shape, and is provided in the narrow bent part 934a extended to the edge of the edge of the lead wire 922 side, and is provided in the front-end | tip of the said bent part 934a. A wide contact portion 934b is formed, and the contact portion 934b is formed in a substantially V-shape to insert the lead wire 922.

In the conductive portion 934, the bent portion 934a is bent so that the contact portion 934b and the lead wire 922 contact each other. However, when the temperature of the sleeve 930 reaches about 140 [deg.] C, the bent portion 934a is bent. The contact portion 934b is separated from the lead wire 922 so that the angle becomes shallow so that the sleeve 930 and the lead wire 922 are insulated. Therefore, even when overcurrent flows and the sleeve 930 becomes high temperature, when mounted in illumination apparatuses, such as a backlight unit, resin members, such as an optical sheet, can be prevented from deforming by the heat.

In addition, the conductive portion 934 does not necessarily need to be made of bimetal, and may have a configuration that does not deform. In that case, the contact portion 934b and the lead wire 922 may be welded.

<Modification Example 11>

19 is an enlarged cross-sectional view showing one end portion of the cold cathode discharge lamp of the modification 11. The cold cathode discharge lamp 1000 shown in FIG. 19 is substantially the same as the cold cathode discharge lamp 1 of this embodiment except that the sleeve 1030 has a different configuration. Therefore, only the configuration of the sleeve 1030 will be described in detail, and the description of other configurations will be simplified.

The cold cathode discharge lamp 1000 includes a glass bulb 1010 having a phosphor layer 1016 formed on an inner surface thereof, an electrode 1020 disposed in an end portion 1012 of the glass bulb 1010, and a sleeve provided at the end portion thereof. 1030 and an emitter 1040 installed on the inner surface of the glass bulb 1010. The electrode 1020 is electrically connected to the sleeve 1030 via a lead wire 1022 composed of an inner lead wire 1022a and an outer lead wire 1022b sealed to the sealing portion 1014.

The sleeve 1030 is made of an alloy of iron and nickel, and includes a cap portion 1031 which is a main body, and a tubular portion 1032 extending to an end portion of the cap portion 1031 that is closed. As the material of the sleeve 1030, a copper alloy such as phosphor bronze, brass, and nickel silver can be used.

The cap portion 1031 is inserted from the outside to cover the outer surface of the end portion 1012 of the glass bulb 1010. In addition, although the clearance gap is not provided in the figure between the cap part 1031 and the glass bulb 1010, the clearance may be provided.

An opening 1033 for inserting the external lead wire 1022b is provided at the end of the cap portion 1031 on the closed side, and the opening 1033 and the inside of the capillary portion 1032 communicate with each other. The outer lead wire 1022b is welded to the capillary portion 1032 by resistance welding, laser welding, or the like in the state of being inserted into the capillary portion 1032 through the opening 1033 inside the cap portion 1031. The electrode 1020 and the sleeve 1030 are electrically connected by the part. The external lead wire 1022b and the capillary portion 1032 may be connected by caulking.

The sleeve 1030 is electrically connected to a lamp holder (not shown) that supports the end portion 1012 of the cold cathode discharge lamp 1000 when the cold cathode discharge lamp 1000 is mounted on a lighting device (not shown). .

In addition, the slit may be provided in the sleeve 1030. The shape of the end portion 1012 of the glass bulb 1010 is easily irregular, and a dimensional error is likely to occur between the outer diameter of the glass bulb 101 and the inner diameter of the sleeve 1030. However, if the slit is provided in the sleeve 1030, even if such a dimensional error occurs, the slit absorbs the dimensional error, and the inner surface of the sleeve 1030 and the outer surface of the glass bulb 1010 can be in close contact, The sleeve 1030 may be stably fixed to the end portion 1012 of the glass bulb 1010.

<Modification example 12>

20 is an enlarged cross-sectional view showing one end portion of the cold cathode discharge lamp of Variation 12; The cold cathode discharge lamp 1100 shown in FIG. 20 is substantially the same as the cold cathode discharge lamp 1 of the modification 11 except for the shape of the sleeve 1130. Therefore, only the configuration of the sleeve 1130 will be described in detail, and the description of the other configuration will be simplified.

The cold cathode discharge lamp 1100 includes a glass bulb 1110 having a phosphor layer 1116 formed therein, an electrode 1120 disposed in an end portion 1112 of the glass bulb 1110, and a sleeve provided at the end portion thereof. 1130 and an emitter 1140 installed on an inner surface of the glass bulb 1110. The electrode 1120 is electrically connected to the sleeve 1130 through a lead wire 1122 including an inner lead wire 1122a and an outer lead wire 1122b sealed to the sealing portion 1114.

Sleeve 1130 is inserted at end 1112 of glass bulb 1110 to cover its outer surface. An end portion of the closing side of the sleeve 1130 is shaped to cause a small hardening toward the end edge, and an opening 1131 is provided at the end edge of the smallest diameter. The outer lead wire 1122b is welded to the sleeve 1130 by resistance welding, laser welding, or the like with the tip inserted into the opening 1131. The electrode 1120 and the sleeve 1130 are connected to each other by the welding portion. It is electrically connected.

The sleeve 1130 is configured to easily insert the external lead wire 1122b into the opening 1131 because the end portion on the side of closing the sleeve 1130 is caused to be shaped as described above.

In addition, a slit may be provided in the sleeve 1130. The shape of the end portion 1112 of the glass bulb 1110 is easily irregular, the dimensional error is likely to occur between the outer diameter of the glass bulb 1110 and the inner diameter of the sleeve 1130. However, if the slit is provided in the sleeve 1130, even if such a dimensional error occurs, the slit absorbs the dimensional error, and the inner surface of the sleeve 1130 and the outer surface of the glass bulb 1110 may be in close contact. The sleeve 1130 may be stably fixed to the end portion 1112 of the glass bulb 1110.

<Modification Example 13>

FIG. 21 is an enlarged cross-sectional view showing one end portion of a cold cathode discharge lamp of Variation 13. FIG. The cold cathode discharge lamp 1200 shown in FIG. 21 is substantially the same as the cold cathode discharge lamp 1 of the modified example 12 except for the shape of the sleeve 1230. Therefore, only the configuration of the sleeve 1230 will be described in detail, and the description of other configurations will be simplified.

The cold cathode discharge lamp 1200 includes a glass bulb 1210 having a phosphor layer 1216 formed on an inner surface thereof, an electrode 1220 disposed in an end 1212 of the glass bulb 1210, and a sleeve installed at the end thereof. 1230 and an emitter 1240 provided on an inner surface of the glass bulb 1210. The electrode 1220 is electrically connected to the sleeve 1230 through a lead wire 1222 composed of an inner lead wire 1222a and an outer lead wire 1222b sealed to the sealing portion 1214.

The sleeve 1230 includes a cap portion 1231 which is a main body, and a capillary portion 1232 extending at an end portion of the cap portion 1231 on the closing side of the cap portion 1231. The cap portion 1231 is inserted from the outside to cover the outer surface of the end portion 1212 of the glass bulb 1210. An end portion of the cap portion 1231 on the closing side has a small induction shape toward the end edge, and an opening 1233 for inserting the external lead wire 1222b is provided at the end edge of the smallest diameter. The opening 1233 and the interior of the tubular portion 1232 communicate with each other.

The outer lead wire 1222b is welded to the tubular portion 1232 by resistance welding, laser welding, or the like in the state of being inserted into the tubular portion 1232 through the opening 1233 at the inside of the cap portion 1231. The electrode 1220 and the sleeve 1230 are electrically connected by this. In addition, the external lead wire 1222b and the tubular part 1232 may be connected by caulking.

The sleeve 1230 has a configuration in which the outer end of the lead 1222b is easy to be inserted into the opening 1231 because the end portion of the sleeve 1230 is in the shape of causing as described above. Moreover, since it has the tubular part 1232, it is the structure which is easy to connect the external lead wire 1222b by welding or caulking.

In addition, a slit may be provided in the sleeve 1230. The shape of the end portion 1212 of the glass bulb 1210 is easily irregular, the dimensional error is likely to occur between the outer diameter of the glass bulb 1210 and the inner diameter of the sleeve 1230. However, when the slit is provided in the sleeve 1230, the slit absorbs the dimensional error even when such a dimensional error occurs, and the inner surface of the sleeve 1230 and the outer surface of the glass bulb 1210 can be in close contact. The sleeve 1230 may be stably fixed to the end portion 1212 of the glass bulb 1210.

<Other variants>

As mentioned above, although the cold cathode discharge lamp of this embodiment was demonstrated based on embodiment, the discharge lamp of this invention is not limited to the above. For example, the discharge lamp of the present invention may be a discharge lamp in which the configurations of the present embodiment and the first to thirteenth modifications are appropriately combined. In addition, the discharge lamp of this invention is not limited to a cold cathode discharge lamp. The emitter may be provided not only on one end side of the glass bulb but also on both end sides. Moreover, the following modified examples can also be considered.

1. About Glass Bulb

(1) About ultraviolet absorption

Ultraviolet rays of 254 [nm] or 313 [nm] can be absorbed by doping a predetermined amount of a transition metal oxide into glass, which is a material of a glass bulb, depending on its kind. Specifically, for example, in the case of titanium oxide (TiO ₂ ), by absorbing 254 [nm] ultraviolet rays by doping at a composition ratio of 0.05 [mol%] or more, 313 [nm] by doping with a composition ratio of 2 [mol%] or more UV light can be absorbed. However, when titanium oxide is doped more than composition ratio 5.0 [mol%], glass will devitrify, It is preferable to dope in the composition ratio 0.05 [mol%] or more and 5.0 [mol%] or less. Do.

In the case of cerium oxide (CeO ₂ ), ultraviolet rays of 254 [nm] can be absorbed by doping with a composition ratio of 0.05 [mol%] or more. However, when cerium oxide is doped more than 0.5 [mol%], since glass will be colored, it is preferable to dope cerium oxide in the range of 0.05 [mol%] or more and 0.5 [mol%] or less. . Moreover, since doping tin oxide (SnO) in addition to cerium oxide can suppress coloring of the glass by cerium oxide, cerium oxide can be dope to composition ratio 5.0 [mol%] or less. In this case, when cerium oxide is doped with a composition ratio of 0.5 [mol%] or more, ultraviolet rays of 313 [nm] can be absorbed. However, also in this case, when cerium oxide is doped more than 5.0 [mol%], glass will devitrify.

In the case of zinc oxide (ZnO), ultraviolet rays of 254 [nm] can be absorbed by doping with a composition ratio of 2.0 [mol%] or more. However, when zinc oxide is doped more than the composition ratio of 20 [mol%], glass may be devitrified. Therefore, it is preferable to dope zinc oxide in the range of 2.0 [mol%] or more and 20 [mol%] or less. .

In the case of iron oxide (Fe ₂ O ₃ ), ultraviolet rays of 254 [nm] can be absorbed by doping with a composition ratio of 0.1 [mol%] or more. However, when iron oxide is doped more than composition ratio 2.0 [mol%], since glass will color, it is preferable to dope iron oxide in the range of composition ratio 0.01 [mol%] or more and 2.0 [mol%] or less.

(2) About infrared transmission coefficient

It is preferable to adjust the infrared transmittance coefficient which shows the water content in glass so that it may become 0.3 or more and 1.2 or less, especially 0.4 or more and 0.8 or less. When the infrared transmittance coefficient is 1.2 or less, low dielectric tangent can be easily applied to high voltage application lamps such as external electrode fluorescent lamps (EEFL) or long cold cathode fluorescent lamps. Further applicable.

In addition, the infrared transmittance coefficient X can be represented by the following equation.

X = (log (a / b)) / t

a: transmittance at the minimum point in the vicinity of 3840 [cm ⁻¹ ] [%]

b: transmittance [%] of the minimum point near 3560 [cm ^-1 ]

t: thickness of glass

(3) About the shape of the glass bulb

The shape of the glass bulb is not limited to a straight pipe shape, but may be, for example, an L shape, a U shape, a U shape, a spiral shape, or the like. The cross section cut perpendicularly to the tube axis is not limited to a substantially circular one, but may be, for example, a flat shape such as a track shape or a half moon corner shape or an elliptical shape.

2. About phosphor

The phosphor constituting the phosphor layer is also not limited to the above. As shown below, it can obtain by selecting suitably from various viewpoints.

For example, the blue phosphor is in the range of 430 [nm] or more and 460 [nm] or less, the green phosphor is in the range of 510 [nm] or more and 550 [nm] or less, and the red phosphor is 600 [nm] or more and 780 [nm]. Those having an emission peak in the following ranges can be used, respectively.

(1) About ultraviolet absorption

For example, in recent years, polycarbonate with good dimensional stability has been used for the diffusion plate which closes the opening of the backlight unit as the liquid crystal color television is enlarged. This polycarbonate is easily deteriorated by ultraviolet rays having a wavelength of 313 [nm] at which mercury emits light. In such a case, a phosphor that absorbs ultraviolet rays having a wavelength of 313 [nm] may be used. Moreover, the fluorescent substance which absorbs an ultraviolet-ray of 313 [nm] is the following.

(a) blue

Europium-manganese-activated barium-strontium-magnesium aluminate [Ba _1-xy Sr _x Eu _y Mg _1-z Mn _z Al ₁₀ O ₁₇ ], or [Ba _1-xy Sr _x Eu _y Mg _2-z Mn _z Al ₁₆ O ₂₇ ]

Here, it is preferable that x, y, z are the numbers which satisfy | fill the conditions which are 0 <= x <= 0.4, 0.07 <= y <0.25, and 0 <= z <0.1, respectively.

With such a phosphor, for example, europium resurrection barium-magnesium aluminate _{[BaMg 2 Al 16 O 27: Eu} 2 + ], _{[BaMg 2 Al 10 O 17: Eu} 2 + ] (abbreviation: BAM-B) or, europium Revitalized barium-strontium-magnesium aluminate [(Ba, Sr) Mg ₂ Al ₁₆ O ₂₇ : Eu ²⁺ ], ((Ba, Sr) MgAl ₁₀ O ₁₇ : Eu ²⁺ ] (abbreviation: SBAM-B) have.

(b) green

Manganese-activated magnesium gallate (MgGa ₂ O ₄ : Mn ²⁺ ) (abbreviation: MGM)

Manganese-activated cerium-magnesium-zinc aluminate (Ce (Mg, Zn) Al ₁₁ O ₁₉ : Mn ²⁺ (abbreviation: CMZ))

Terbium-activated cerium-magnesium aluminate (CeMgAl ₁₁ O ₁₉ : Tb ³⁺ ) (abbreviation: CAT)

Europium-manganese-activated barium-strontium-magnesium aluminate [Ba _1-xy Sr _x Eu _y Mg _1-z Mn _z Al ₁₀ O ₁₇ ] or [Ba _1-xy Sr _x Eu _y Mg _2-z Mn _z Al ₁₆ O ₂₇ ]

Here, x, y, and z are the numbers which satisfy | fill the conditions which are 0 <= x <= 0.4, 0.07 <= y <0.25, 0.1 <= z <= 0.6, respectively, It is preferable that z is 0.4 <= x <0.5.

With such a phosphor, for example, europium-manganese resurrection barium-magnesium aluminate four byte _{[BaMg 2 Al 16 O 27: Eu} 2 +, Mn 2 + ], ^{_{[BaMgAl 10 O 17: Eu 2 +}} , Mn 2 + ] (Abbreviation: BAM-G), europium-manganese-activated barium-strontium-magnesium aluminate [(Ba, Sr) Mg ₂ Al ₁₆ O ₂₇ : Eu ²⁺ , Mn ²⁺ ], [(Ba, Sr) MgAl ₁₀ O ₁₇ : Eu ²⁺ , Mn ²⁺ ] (abbreviation: SBAM-G).

(c) red

Europium-activated yttrium phosphovanadate [Y (P, V) O ₄ : Eu ³⁺ ] (abbreviation: YPV)

Europium revitalized yttrium vanadate (YVO ₄ : Eu ³⁺ ) (abbreviation: YVO)

Europium revitalized yttrium oxysulfite (Y ₂ O ₂ S: Eu ³⁺ ) (abbreviation: YOS)

Magnesium fluoride, manganese resurrection germanium acid salts _{[3.5MgO · 0.5MgF 2 · GeO 2:} Mn 4+ ] (abbreviation: MFG)

Dysprosium-activated yttrium vanadate [YVO ₄ : Dy ³⁺ ] (a two-component luminescent phosphor of red and rust, abbreviated YDS)

Moreover, you may mix and use the fluorescent substance of another compound with respect to one kind of emission color. For example, only BAM-B (absorbs 313 [nm]) in blue, LAP (does not absorb 313 [nm]) and BAM-G (absorbs 313 [nm]) in green, and red Phosphors of YOX (which does not absorb 313 [nm]) and YVO (which absorbs 313 [nm]) may be used. In such a case, it is almost possible to prevent ultraviolet rays from leaking out of the glass tube by adjusting the phosphor absorbing the wavelength of 313 [nm] to be larger than 50 [%] in the total weight composition ratio as described above. Therefore, when the phosphor layer 105 includes a phosphor that absorbs 313 [nm] ultraviolet rays, deterioration due to ultraviolet rays such as a diffusion plate made of polycarbonate (PC) covering the opening of the backlight unit is suppressed and the backlight is suppressed. The characteristic as a unit can be maintained for a long time.

Here, "absorbing 313 [nm] ultraviolet rays" indicates the intensity of an excitation wavelength spectrum near 254 [nm] (excitation wavelength spectrum is excitation light emission while changing the wavelength of the phosphor, and the excitation wavelength and emission intensity are plotted). The intensity of the excitation wavelength spectrum of 313 [nm] at 100 [%] is defined as 80 [%] or more. That is, the phosphor which absorbs 313 [nm] ultraviolet rays is a phosphor which can absorb 313 [nm] ultraviolet rays and convert it into visible light.

(2) About high color reproduction

In the liquid crystal display device represented by liquid crystal color television, a range of chromaticity that can be reproduced in a cold cathode fluorescent lamp or an external electrode fluorescent lamp used as a light source of a backlight unit of the liquid crystal display device is recently accompanied by high color reproduction which is part of high quality. There is a request of enlargement.

In response to such a request, for example, by using the following phosphors, the chromaticity range can be expanded than in the case of using the phosphors in the examples. Specifically, in the CLE1931 chromaticity diagram, the chromaticity coordinate values of the phosphor for high color reproduction are located at coordinates that widen the color reproduction range, including a triangle formed by connecting the chromaticity coordinate values of the three phosphors used in the examples. .

In addition, the chromaticity coordinate value of the fluorescent substance (powder) described below rounds off the value measured with the spectroscopic analysis apparatus (MCPD-7000) by Otsuka Electronics Co., Ltd. at four decimal places. In addition, this chromaticity coordinate value is a representative value of each phosphor material, and may show a slightly different value based on a measuring method (a measuring principle).

(a) blue

Europium-activated strontium-chloroapatite [Sr ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu ²⁺ ] (abbreviation: SCA), chromaticity coordinates: x = 0.153, Y = 0.030

In addition to the above, europium-activated strontium-calcium-barium-chloroapatite [(Sr, Ca, Ba) ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu ²⁺ ] (abbreviation: SBCA) can also be used, and the said wavelength 313 [nm] SBAM-B, which can absorb ultraviolet rays, can also be used for high color reproduction.

(b) green

BAM-G, chromaticity coordinates: x = 0.136, y = 0.572

CMZ, chromaticity coordinates: x = 0.164, y = 0.722

CAT, chromaticity coordinates: x = 0.284, y = 0.635

Terbium-manganese-activated cerium-magnesium aluminate [CeMgAl ₁₁ O ₁₉ : Tb ³⁺ , Mn ²⁺ ] (abbreviated number: CAM), chromaticity coordinates: x = 0.256, y = 0.657

Manganese-activated zinc silicate [Zn ₂ SiO ₄ : Mn ²⁺ ] (abbreviation: ZSM), chromaticity coordinates: x = 0.248, y = 0.700

As described above, they can also absorb ultraviolet rays having a wavelength of 313 [nm], and in addition to the three phosphor particles described herein, MGM can also be used for high color reproduction.

(c) red

YOS, chromaticity coordinates: x = 0.658, y = 0.330

YVO, chromaticity coordinates: x = 0.661, y = 0.328

MFG, chromaticity coordinates: x = 0.708, y = 0.288

In addition, they can also absorb ultraviolet rays having a wavelength of 313 [nm] as described above, and in addition to the three phosphor particles described herein, YPV and YDS can also be used for high color reproduction.

The chromaticity coordinate values described above are representative values measured only by the powder of each phosphor, and the chromaticity coordinate values represented by the powder of each phosphor due to the measuring method (measurement principle) and the like are different from the values described above. There may be slightly different cases. For reference, the chromaticity coordinate values of the powder of each phosphor of Example 1 are YOX (x = 0.643, y = 0.348), LAP (x = 0.351, y = 0.585), BAM-B (x = 0.148, y = 0.055). Consists of

In addition, the fluorescent substance used for emitting red, green, and blue colors is not limited to one type for each wavelength, You may use combining several types.

Here, the case where a phosphor layer is formed using said fluorescent particle for high color reproduction is demonstrated. The evaluation here is based on the area of the NTSC triangle connecting the chromaticity coordinate values of the three primary colors of the NTSC standard within the CIE1931 chromaticity diagram. The ratio of the area of the connected triangles (hereinafter referred to as NTSC ratio) is performed.

For example, using BAM-B in blue, BAM-G in green, and YVO in green (Example 1), the NTSC ratio is 92 [%], and SCA in blue, BAM-G in green, and YVO in red. If you use (Example 2) the NTSC ratio is 100 [%] and if you use SCA in blue, BAM-G in green, and YOX in red (Example 3), the NTSC ratio is 95 [%]. In comparison, the luminance can be improved by 10 [%].

In addition, the chromaticity coordinate value used for evaluation here is measured in the state made into the liquid crystal display device with a lamp etc. attached.

[Lighting device]

<First Embodiment>

22 is an exploded perspective view showing the lighting apparatus of the first embodiment. As shown in Fig. 22, the illuminating device of the first embodiment is a backlight unit 1300 of a direct type, and has a flat rectangular parallelepiped-shaped housing 1302 with one side open, and housed inside the housing 1302. A plurality of cold cathode discharge lamps 1 of the present invention and optical sheets 1304 covering the openings of the housing 1302 are provided.

The housing 1302 is, for example, made of polyethylene terephthalate (PET) resin, and metal, such as silver or aluminum, is deposited on the inner surface thereof to form a reflective surface 1306. The housing 1302 may be made of a material other than resin, for example, a metal material such as aluminum or a cold rolled material (for example, SPCC). In addition to the metal-deposited film on the inner reflective surface 1306, a reflective sheet having a high reflectance is added to the housing 1302 by adding calcium carbonate, titanium dioxide (TiO ₂ ), or the like to a polyethylene terephthalate (PET) resin. It may be attached.

Inside the housing 1302, a cold cathode discharge lamp 1, a pair of sockets 1308, and a pair of covers 1310 are disposed.

The pair of sockets 1308 are arranged substantially parallel at intervals in the longitudinal direction of the housing 1302. The socket 1308 is a plate (band material) made of a copper alloy such as phosphor bronze, for example, and a pair of sandwich pieces 1308A into which the sleeves 30 and 31 of the cold cathode discharge lamp 1 are inserted. And the connecting piece 1308B which electrically connects these adjacent clamping pieces 1308A at the lower edge is made continuous in the width direction of the housing 1302. When the sleeves 30 and 31 of the cold cathode discharge lamp 1 are inserted into the pair of sandwich pieces 1308A, the cold cathode discharge lamp 1 is supported by the pair of sandwich pieces 1308A. The sandwich piece 1308A and the sleeves 30 and 31 are electrically connected to each other. The cold cathode discharge lamp 1 mounted in the pair of sockets 1308 is supplied with electric power through the socket 1308 from the lighting circuit 1524 (see FIG. 24) of the backlight unit 1300.

The cover 1310 is for securing insulation between the pair of sandwich pieces 1308A and the pair of sandwich pieces 1308A adjacent thereto.

The optical sheet 1304 is comprised by the diffusion plate 1312, the diffusion sheet 1314, and the lens sheet 1316, for example. The diffusion plate 1312 is a plate-shaped body made of polymethyl methacrylate (PMMA) resin, for example, and is disposed to cover the opening of the housing 1302. The diffusion sheet 1314 is made of polyester resin, for example. The lens sheet 1316 is, for example, adhesion of acrylic resin and polyester resin. These optical sheets 1304 are arrange | positioned so that they may overlap each other in the diffuser plate 1312 one by one.

Since the backlight unit 1300 as described above includes the cold cathode discharge lamp 1 of the present invention as a main light source, the dark starting characteristic is good.

Second Embodiment

Fig. 23 is a partially cutaway perspective view of the lighting apparatus of the second embodiment. As shown in FIG. 23, the lighting apparatus of the second embodiment is an edge light type backlight unit 1400, which includes a reflector plate 1410, a cold cathode discharge lamp 1 of the present invention, a socket (not shown), and a light guide plate ( 1420, a diffusion sheet 1430, and a prism sheet 1440.

The reflecting plate 1410 is disposed to surround the light guide plate 1420 except for the liquid crystal panel side (arrow Q), and has a bottom portion 1411 covering the bottom surface and a side where the cold cathode discharge lamp 1 is disposed. The light guide plate 1420 includes a side surface portion 1412 that covers the side surface except for the side surface, and a curved side surface portion 1413 that covers the periphery of the cold cathode discharge lamp 1, and emits light emitted from the cold cathode discharge lamp 1. Reflects to the liquid crystal panel (not shown) side (arrow Q). In addition, the reflecting plate 1410 is formed by depositing silver on a film-shaped PET, or laminating with a metal foil such as aluminum.

The socket has a configuration substantially the same as that of the backlight unit 1300 which is the lighting apparatus of the first embodiment. 23, the edge part of the cold cathode discharge lamp 1 is abbreviate | omitted for the convenience of illustration.

The light guide plate 1420 is used to guide the light reflected by the reflector 1410 to the liquid crystal panel, and is formed of, for example, a transparent plastic, and is stacked on the bottom 1411 of the reflector 1410. Moreover, polycarbonate (PC) resin and cycloolefin resin (COP) can be applied as a material.

The diffusion sheet 1430 is for expanding the view, and is made of, for example, a film having a diffusion transmission function made of polyethylene terephthalate resin or polyester resin and laminated on the light guide plate 1420.

The prism sheet 1440 is for improving luminance, and is formed of, for example, a sheet to which an acrylic resin and a polyester resin are attached, and are stacked on the diffusion sheet 1430. In addition, a diffusion plate may be further stacked on the prism sheet 1440.

In addition, in the present embodiment, except for a portion in the circumferential direction of the cold cathode discharge lamp 1 (the light guide plate 1420 side when inserted into the lighting device 1400), it is reflected on the outer surface of the glass bulb 101. An aperture type lamp provided with a sheet (not shown) may be used.

Since the backlight unit 1400 includes the cold cathode discharge lamp 1 of the present invention as a main light source, the dark starting characteristic is good.

[LCD]

24 shows an outline of the liquid crystal display device of the embodiment. As shown in FIG. 24, the liquid crystal display device 1500 is, for example, a 32-inch liquid crystal television, and a pattern disposed on the back of the liquid crystal display unit 1522 and the liquid crystal display unit 1522 including a liquid crystal panel. The backlight unit 1300 and the lighting circuit 1524 of the present invention are provided.

The liquid crystal display unit 1522 is well known and includes a liquid crystal panel (color filter substrate, liquid crystal, TFT substrate, etc.) (not shown), a drive module, etc. (not shown), and displays a color image based on an image signal from the outside. To form.

The lighting circuit 1524 lights the cold cathode discharge lamp 1 (FIG. 22) inside the backlight unit 1300. The cold cathode discharge lamp 1 is operated at a lighting frequency of 40 [kHz]-100 [kHz] and a lamp current of 3.0 [mA]-25 [mA].

In addition, although the backlight unit 1300 of the first embodiment is used as the light source device of the liquid crystal display device 1500 in FIG. 24, the present invention is not limited thereto. For example, the backlight unit 1400 of the second embodiment may also be used. good.

Since the liquid crystal display device 1500 as described above includes the cold cathode discharge lamp 1 of the present invention as a main light source, the dark startup characteristic is good.

The present invention can be widely applied to a discharge lamp. In particular, it is possible to provide a discharge lamp having high mounting accuracy for the lamp holder of the lighting device.

Claims (20)

In a discharge lamp provided with an electrode disposed inside at least one end of the glass bulb, the metal conductor electrically connected to the electrode on the outer periphery of the end, As the position where the electric field strength is high enough to attract the ion bombardment at the start in the glass bulb, A discharge lamp, characterized in that an emitter is provided between the proximity conductor and the electrode in a state where it is mounted on a lighting device provided with a proximity conductor electrically insulated from a current path of the lamp. The method of claim 1, And the emitter is disposed on a track reaching the electrode at the shortest distance from the proximity conductor while avoiding the metal conductor between the proximity conductor and the electrode. The method of claim 2, The emitter is a discharge lamp, characterized in that consisting of a cesium compound. The method of claim 1, And said emitter is disposed on an inner surface of the glass bulb where the metal conductor is not provided. The method of claim 4, wherein The metal conductor has a cylindrical shape having a slit or cutout, and the emitter is disposed on an inner surface of a portion of the glass bulb where the slit or cutout is located. The method of claim 5, wherein And a secondary emitter separate from the emitter is provided on the electrode. The method of claim 6, And an end edge at the center side of the glass bulb of the metal conductor is located at the center side of the glass bulb rather than an end edge at the center side of the glass bulb of the electrode. The method of claim 7, wherein The emitter is a discharge lamp, characterized in that consisting of a cesium compound. The method of claim 4, wherein And a secondary emitter separate from the emitter is provided on the electrode. The method of claim 1, And said emitter is provided on an inner surface of said glass bulb where said metal conductor is not provided. The method of claim 1, And said emitter is provided on an outer surface of a portion of said electrode where said metal conductor is not provided. The method of claim 11, The metal conductor has a cylindrical shape having a slit or cutout, and the emitter is disposed on an outer surface of the portion where the slit or cutout is located in the electrode. The method of claim 12, The emitter is a discharge lamp, characterized in that consisting of a cesium compound. The method of claim 1, The electrode is a cylindrical hollow electrode having a bottom surface, and the emitter is disposed on an inner surface of the barrel of the electrode. The method of claim 14, And an end edge at the center side of the glass bulb of the metal conductor is located at the center side of the glass bulb rather than an end edge at the center side of the glass bulb of the electrode. The method of claim 15, The emitter is a discharge lamp, characterized in that consisting of a cesium compound. The method of claim 2, And said emitter is disposed on an inner surface of a portion of the glass bulb where the metal conductor is not provided on an outer circumference thereof. The method of claim 2, The electrode is a cylindrical hollow electrode having a bottom surface, and the emitter is disposed on the inner surface of the tube of the discharge lamp. An illumination device comprising the discharge lamp according to claim 1. A liquid crystal display device comprising the illuminating device according to claim 19.

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