JPH07240173A - Discharge lamps and lamp devices - Google Patents

Abstract

(57) [Summary] [Object] An object of the present invention is to provide a discharge lamp that increases the amount of light emission and obtains high luminous efficiency, and a lamp device equipped with this lamp. In a lamp L including a glass bulb 1, a discharge sustaining medium sealed in the glass bulb 1, and a mount 3 having a discharge electrode 6 disposed in the bulb 1, the mount 3 is sealed. A lamp L in which a discharge electrode 6 formed with substances 8 and 9 is connected to a sealing wire 5 and a lamp device in which the lamp is mounted on a fixture or the like. [Effect] Since the discharge electrode is directly connected to the sealing wire without interposing the internal lead wire, the height (mount height) from the sealing portion to the tip of the electrode is reduced, and the distance between the opposing electrodes is reduced. Since the interval is widened and the discharge path is long, the amount of light emission increases correspondingly, and high light emission efficiency can be obtained. Further, if the distance between the electrodes is the same, the length of the bulb can be shortened and the lamp can be downsized because there is no internal lead wire.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a discharge lamp used in office automation equipment such as personal computers and word processors, display equipment such as televisions, lighting equipment and the like, and a lamp device such as the above-mentioned display equipment and lighting equipment equipped with this lamp. .

[0002]

2. Description of the Related Art In recent years, small-sized personal computers and televisions using a liquid crystal display device (hereinafter abbreviated as LCD) have been made thinner and have high brightness. For example, a fluorescent lamp used in a backlight device for illuminating this LCD has a small input, is smaller in diameter and smaller in power consumption than a fluorescent lamp for general lighting, and has high brightness and high color rendering at the same time. It is required that the material has a long life span. In particular, since these devices are for consumer use, the lamps are not replaced in principle, and a life of 10,000 hours or more is required.

For this reason, in the compact fluorescent lamp for a backlight device, an optimum electrode design is required from the viewpoint of life as well as current and voltage, the kind of rare gas to be enclosed, the amount of mercury, etc. so as to be compatible with low power consumption. Has been done.

In order to reduce the size of the lamp as described above, it is necessary to reduce the size of the electrode portion. In order to reduce the temperature, the temperature rises quickly, the brightness is high, and the power consumption is reduced. There is a hot cathode type in which a filament coil in which an element wire is wound twice is used.

However, since the filament coil of this hot cathode type has a small diameter, it is difficult to support the filament coil, and it is weak against vibration and impact, and the filament coil is supported in the sleeve. However, the structure becomes complicated, and the filament coil having a small diameter cannot hold a large amount of the electron emissive material and the getter.

Therefore, in the discharge lamp in which the bulb has a diameter of 10 mm or less, a cold cathode type electrode is often used as the electrode, but the shape of the cold cathode type electrode formed in the mount portion in the bulb and Retention of encapsulating materials such as mercury-releasing metals, electron emissive materials and getters has been a problem.

As a mount having this cold cathode type discharge electrode, a mount using a plate-shaped electrode or a bent electrode such as a letter shape as seen in JP-A-4-296441 is also disclosed. Japanese Unexamined Patent Publication No. 64-33844 and Japanese Unexamined Patent Publication No. 4-71156 use a cylindrical electrode.
Further, Japanese Patent Application Laid-Open No. 2-117062 describes a plate-shaped electrode using a recess for accommodating a mercury-releasing metal.

Although not clear in some of these publications, it can be seen from the drawings that the electrode portion is arranged apart from the sealing portion at the end portion of the bulb. This is because in a normal mount configuration, a sealing wire made of dumet wire, which is familiar with glass, is used in the sealing part of the valve. It can be seen from the fact that the external lead wire is connected to the outside and the cold cathode type discharge electrode is attached to the tip portion of the internal lead wire.

[0009]

However, in the structure of the discharge electrode described in the above publication, the mount height (mount height) is high because the electrode is separated from the sealing portion via the internal lead wire. The discharge interval between the electrodes is shortened, and the gap between the electrodes and the sealing part is separated from the discharge path, resulting in darkness and a decrease in the amount of light emitted from the entire lamp. The valve length was too long.

The present invention has been made in view of the above problems,
An object of the present invention is to provide a discharge lamp having a long life while increasing the amount of light emission to obtain high luminous efficiency and a lamp device equipped with this lamp.

[0011]

DISCLOSURE OF THE INVENTION The discharge lamp of the present invention comprises:
In a discharge lamp including a glass bulb, a discharge sustaining medium sealed in the glass bulb, and a mount provided with a discharge electrode arranged in the bulb, the mount seals a discharge electrode formed with a filling substance. It is characterized by being connected to a wire.

Further, it is characterized in that the sealing wire forming the mount has a larger diameter than the external lead wire connected to the sealing wire.

Further, the discharge electrode forming the mount is a cylindrical sleeve, and the sealing substance formed in the sleeve is at least one of a mercury-releasing metal, an electron emissive substance and a getter.

Further, the filling material filled in the discharge electrode composed of the cylindrical sleeve is at least one of a mercury-releasing metal, an electron emissive material and a getter. Further, it is characterized in that the discharge electrode composed of the cylindrical sleeve is filled with mercury-releasing metal and a getter is formed on the outer surface thereof.

Further, the discharge electrode constituting the mount is a plate-shaped body or a rod-shaped body, and the encapsulating substance formed on the plate-shaped body or the rod-shaped body is at least one of a mercury-releasing metal, an electron emitting substance and a getter. Is characterized by.

The glass bulb has an outer diameter of 10 mm.
It is characterized by the following. Furthermore, the lamp device of the present invention is characterized by being equipped with the discharge lamp described above.

[0017]

[Function] Since the discharge electrode is directly connected to the sealing wire to be sealed in the sealing portion of the bulb, the internal lead wire is not required and the mount height (mount height) is lowered, so that the discharge electrodes face each other. Since the distance between the electrodes is increased and the discharge path is lengthened, the amount of light is increased. Further, if the distance between the electrodes is the same, the bulb length can be shortened and the lamp can be downsized. In addition, the cylindrical electrode can be filled with a mercury-releasing metal, an electron emissive substance, or an encapsulating substance such as a getter so as to be easily held, and its wear can be reduced for a long period of time.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 1 is a front view of a discharge lamp used in an LCD backlight device, etc., FIG. 2 is an enlarged front sectional view of a sealing portion including the mount of FIG. 1, and FIG. 3 is taken along line XX in FIG. It is a side sectional view which expands and shows the portion which carried out section.

This discharge lamp is a cold cathode type, for example, a straight tube type fluorescent lamp L of 2.3 W with power consumption of 5 W or less.
The lamp L has a tubular glass bulb 1 made of lead glass with an outer diameter of about 2.6 mm, an inner diameter of about 1.6 mm, and an overall length of about 150 mm.
A mount 31 is arranged at 2.

The inner wall surface of the valve 1 is, for example, blue.
A three-wavelength type phosphor layer 4 in which phosphors having a light emitting region in green and red are mixed is formed, and a rare gas such as argon (Ar) or neon (Ne) alone or as a discharge sustaining medium is formed inside the bulb 1. It is mixed and encapsulated at about 60 torr.

Further, the mounts 31, 31 arranged at both ends of the valve 1 are, as shown enlarged in FIGS. 2 and 3,
A relatively large-diameter sealing wire 5 having an outer diameter of about 1.2 mm, which is made of a Dumet wire or the like having the same coefficient of thermal expansion as the glass of the bulb 1.
(Ni-), stainless steel (Fe-Ni
-Mn), a metal made of tungsten (W), molybdenum (Mo), etc., has an outer diameter of about 1.0 mm and a length of about 3.
A cylindrical sleeve 61 having a thickness of 0 mm and a plate thickness of about 0.1 mm is connected by electric welding as a cold cathode type electrode 6 with its end faces abutting each other. Further, the other end side of the sealing wire 5 has an outer diameter of about 0.1 of copper (Cu) -plated iron (Fe) wire.
An outer lead wire 7 having a diameter smaller than that of the 4 mm-sealed wire 5 is connected by electric welding in a state where the end faces thereof are butted in the same manner as above.

In the sleeve 61, mercury (Hg) and titanium (T), which are enclosed substances as discharge sustaining media, are used.
i) Mercury-releasing metal (Ti3 H
g) 8 is filled.

When the fluorescent lamp L having such a structure is connected to a predetermined high-frequency lighting circuit and energized, a discharge is generated between the electrodes 6 formed of the sleeve 61, and the sleeve 61 is heated to a high temperature so that the outer surface is coated. The temperatures of the obtained getter layer 9 and the mercury-releasing alloy 8 also rise. By this heating, mercury vapor is released from the mercury-releasing metal 8 into the bulb 1, and the discharge collides with the electrons moving in the bulb 1 to emit ultraviolet rays, and the ultraviolet rays are received by the phosphor 4 on the wall of the bulb 1. When excited, a predetermined visible light is emitted to the outside of the bulb 1 to emit light.

In this lamp L, since the sleeve-shaped cold cathode electrode 6 is directly connected to the sealing wire 5 without interposing the internal lead wire, the height from the sealing portion 2 to the tip of the electrode 6 is increased. Since the (mount height) becomes low, that is, the interval between the electrodes 6 facing each other is widened and the discharge path becomes longer, the amount of light emission increases correspondingly and high light emission efficiency can be obtained. Further, if the distance between the electrodes 6 is the same, the bulb length can be shortened and the lamp can be downsized because there is no internal lead wire.

Further, since the sleeve 61 and the sealing wire 5 are connected by electric welding in a state where their end faces are abutted,
It is possible to obtain the sealed portion 2 which is excellent in airtightness without any damage due to welding connection or foreign matter adhesion on the surface layer in the longitudinal direction of the sealing wire 5 and no leakage from the glass of the bulb 1.

Further, since the sealing wire 5 has a relatively large diameter, it can be easily connected to the sleeve 61 and is less likely to be deformed or moved even if pressed by the glass of the bulb 1 melted during sealing. The discharge electrode 6 can be held on the central axis of the bulb 1.

Further, in this lamp L, the mercury-releasing metal 8 need only be put in the sleeve 61, so that a fixed amount of mercury can be enclosed, and the mercury-releasing metal 8 in the sleeve 61 can be maintained as the temperature of the electrode 6 increases during discharge. Since the mercury vapor is gradually released from the above to replenish the bulb 1 with mercury, high luminous efficiency can be maintained for a long time. Also,
Titanium (Ti) that constitutes the mercury-releasing metal 8 has a gettering action, so that the impurity gas in the valve 1 is adsorbed and the valve 1
It is possible to obtain a lamp L having improved light emission characteristics, such as preventing blackening of the light and reducing the luminous flux maintenance factor.

The mercury vapor may be released from the mercury-releasing metal 8 by high-frequency heating after the inside of the valve 1 is exhausted and a rare gas is sealed to hermetically seal the valve 1.

This fluorescent lamp L has a lamp current of about 5 m.
A, the lamp voltage is about 25 when it is lit at a frequency of 40 kHz.
It turned on at 0V. In addition, the total luminous flux was about 8% higher than that of the conventional product, and the luminous efficiency was improved by about 5%.

FIG. 4 shows another embodiment of the mount of the present invention. In the figure, the same parts as those in FIGS. 2 and 3 are designated by the same reference numerals, and the description thereof will be omitted. In the mount 32 of FIG. 4, the inner diameter of the sleeve 62 forming the cold cathode electrode 6 is larger than the outer diameter of the sealing wire 5, the outer diameter is about 1.0 mm, the length is about 3 mm, and the plate thickness is A sealing wire 5 having an outer diameter of about 0.6 mm is inserted into one end of a sleeve 62 of about 0.1 mm, and this portion is connected by welding, caulking, screwing, or the like. Note that the configuration other than this connecting portion and the function and effect thereof are the same as those in the above-described embodiment, and are omitted here.

Further, FIG. 5 shows another embodiment of the mount of the present invention. In the figure, the same parts as those in FIGS. 2 to 4 are designated by the same reference numerals and the description thereof will be omitted. Mount 33 of FIG.
Has a length of about 3 m on the end surface of the sealing wire 5 with an outer diameter of about 1.0 mm.
A cold cathode electrode 6 composed of a plate-like body 63 having a width of m, a width of about 1 mm and a plate thickness of about 0.1 mm is connected. For this connection, a rectangular plate body made of nickel (Ni) or the like is bent into a substantially L shape, and its short side is connected to the end face of the sealing wire 5 by welding.

Then, the cold cathode type electrode 6 of the plate 63 is formed.
A getter comprising a mercury-releasing metal layer 83 formed by coating a powdery mercury alloy (Ti3 Hg) on one side, and a getter made of an alloy powder of zirconium (Zr) and aluminum (Al) on the other side. Getter layer 9 formed by coating layer 9
3 is provided.

When the lamp formed by sealing the mount 33 to the sealing portion at the end of the bulb is energized, a discharge is generated between the electrodes 6 and 6 and the electrodes 6 and 6 made of the plate-shaped body 63 are heated to a high temperature. As a result, the temperatures of the getter layer 93 and the mercury-releasing metal layer 83 applied to the outer surface also rise. As a result of this heating, the getter layer 93 adsorbs the impure gas in the bulb 1, and mercury vapor is released into the bulb 1 from the mercury-releasing metal layer 83. Since the position is close to the sealing portion 2 and the discharge path between the electrodes 6 is long, it is possible to obtain a lamp having a high luminous efficiency and a luminous flux maintenance factor with a small decrease and having improved characteristics.

Further, FIG. 6 shows another embodiment of the mount of the present invention. In the figure, the same parts as those in FIGS. 2 to 5 are designated by the same reference numerals and the description thereof will be omitted. Mount 34 of FIG.
Has an outer diameter of about 1. 0 at the end surface of the sealing wire 5 having an outer diameter of about 1.0 mm.
The discharge electrode 6 is a coil-shaped body 64 formed by winding a wire body made of 0 mm nickel (Ni). And the coiled body 6
The end surface of 4 is aligned with the end surface of the sealing wire 5 and connected by electric welding.

An electron emissive material 94 such as barium oxide (BaO) is provided inside and on the surface of the discharge electrode 6 surrounded by the coiled body 64.

The rare gas emission discharge lamp manufactured by sealing the mount 34 does not generate mercury vapor, but acts as a hot cathode to cause the electron emissive substance 94 to be easily discharged as in the above embodiment. It has the effect of

Then, for example, the fluorescent lamp L shown in FIG. 1 is incorporated and used as a light source of a backlight device as shown in FIG. In FIG. 7, R is a reflecting mirror on which the lamp L is mounted, D is a light diffusing plate placed in the opening of the reflecting mirror R, as a backlight device of a liquid crystal display device such as a personal computer or a television, or a predetermined display. Since the lamp L is used as a backlight device of the display panel P on which the devices are formed and the efficiency of the lamp L is high, it is possible to improve the efficiency of these devices and downsize them.

The present invention is not limited to the above embodiment. For example, the discharge lamp is not limited to a fluorescent lamp, but can be applied to other thin tube low-pressure discharge lamps such as a lamp that emits rare gas. Further, its application is not limited to display, and it can be applied not only to lighting but also to a lamp for ultraviolet irradiation such as sterilization.

Further, the material of the bulb is not limited to lead glass, but may be soft glass such as soda lime glass or hard glass such as aluminosilicate glass, and the shape thereof is not limited to the straight pipe shape, and is U-shaped, W-shaped, It may be bent in a ring shape or may be one in which straight pipe valves are connected in parallel.

As the sealing wire, when the bulb is soft glass, in addition to Dumet wire, nickel-coated Dumet wire or chromium-containing iron alloy wire is used, and when the bulb is hard glass, molybdenum wire, tungsten wire, nickel / cobalt / iron. Although alloy wires and the like have similar thermal expansion coefficients and are used in combination, other materials may be used. Further, the sealing wire may be extended to the outside of the valve to be an external lead wire.

Needless to say, the material of the discharge electrode is selected so as not to be melted or worn by discharge. Further, the cylindrical sleeve may be a sleeve having holes formed in the peripheral wall or a mesh formed by braiding metal wires in a mesh shape. This mesh type has a small heat capacity, the temperature rises quickly at the beginning of discharge and the starting time required can be shortened, and part of the mesh becomes high temperature due to discharge during lighting, and the heat heats the electron emissive material The function becomes low, and thermionic electrons are emitted from that part, and the lamp voltage can be greatly reduced, and mercury in the mercury-releasing alloy also evaporates from the mesh, so that high efficiency and long life of the lamp can be achieved.

Further, in the above-mentioned embodiment, the sleeve forming the cold cathode type electrode is filled with the mercury-releasing metal which is a substance to be enclosed in the bulb, but a getter layer may be formed on the outer surface thereof. Further, the sleeve may be filled with an electron emissive material.

In the case of a discharge lamp of rare gas emission which does not contain mercury (of course, a discharge lamp containing mercury may be used), the sleeve is filled with an electron emissive material.
A getter layer may be formed on the outer surface thereof.

If the amount (capacity or area) of the enclosed substance is insufficient, the same substance, for example, a mercury-releasing alloy is filled in the inside and the outer surface of the sleeve, and the outer surface is covered. It doesn't matter.

The sleeve forming the electrode is made of a metal such as titanium (Ti) or zirconium (Zr), which is a getter material, or an alloy thereof, or another metal such as an alloy of zirconium (Zr) and aluminum (Al). It is also possible to form a getter with the above alloy and form a mercury-releasing metal or an electron emissive substance that exerts another action on the inside or the outside thereof.

Further, when the plate-shaped or coil-shaped discharge electrode shown in FIGS. 5 and 6 is used, the shape is not limited to that of the embodiment and may be V-shaped or linear, and the formation of the enclosed substance. In the same manner as described above, the encapsulating substance may be covered or filled in the front and back surfaces or divided into several sections, or the electrode itself may be formed of the encapsulating substance.

Further, the discharge electrodes are not limited to those provided in a pair, and may have three or more electrodes such as an intermediate electrode,
At least one of the plurality of electrodes may have the structure of the present invention.

Further, the material of the mercury-releasing alloy used in the present invention is not limited to those described in the examples, and may be an alloy of mercury (Hg) and another metal such as indium (In). Alternatively, a mixture of this mercury-releasing metal with a getter material made of an alloy of zirconium (Zr) and aluminum (Al) may be used.

Further, the electron emissive substance is not limited to the above-mentioned alkaline earth oxides ((Ba, Ca, Sr) O) but (Ba, Ca, Sr) O, Ba-MO (M; T).
a, Al, V, W, Ti), Ba-Ca-MO (M;
Ta, Al, V, W, Ti) and the like, or a combination thereof, or a material to which a small amount of Al ₂ O ₃ , ZrO ₂ , or Sr ₂ O ₃ is added may be used.

Further, the getter is not limited to the above-mentioned alloy of zirconium (Zr) and aluminum (Al), and zirconium (Zr), titanium (Ti), barium (Ba), phosphorus (P), and other simple substances. Alternatively, it may be an alloy.

Furthermore, the shape of the electrode and the material type, amount, and form of the above-mentioned mercury-releasing alloy, filling material such as electron-emitting material and getter, the filling form, etc., are the rated characteristics of the lamp (current, life, etc.) and bulb tube. It may be appropriately determined according to the diameter and the pipe length.

Furthermore, the rare gas sealed in the lamp is not limited to argon (Ar), but neon (Ne) and xenon (X).
The gas may be a gas in which e), krypton (Kr) or the like is used singly or in a mixture, and the mixing ratio and the filling pressure may be appropriately determined according to the lamp characteristics.

Furthermore, the lamp device according to the present invention can be applied not only to a display device such as a backlight of a liquid crystal display device, but also to general lighting equipment, an ultraviolet irradiation device and the like.

[0054]

As described above in detail, according to the present invention, since the discharge electrode is directly connected to the sealing wire without the intermediary of the internal lead wire, from the sealing portion to the electrode tip portion. Height (mount height) is decreased, that is, the interval between both electrodes facing each other is expanded and the discharge path is lengthened, so that the amount of light emission is increased by that amount and high light emission efficiency is obtained. Further, if the distance between the electrodes is the same, the length of the bulb can be shortened and the lamp can be downsized because there is no internal lead wire.

Further, in the lamp using the sleeve as the electrode, a fixed amount of mercury can be enclosed, and mercury vapor is gradually discharged from the mercury-releasing metal in the sleeve along with the lighting of the electrode, which is heated during discharge, into the bulb. Since mercury is supplied, high luminous efficiency can be maintained for a long time. Further, when a substance having a gettering action is mixed with the mercury-releasing alloy, an impure gas in the bulb is adsorbed, blackening of the bulb is prevented, and the luminous flux maintenance rate is less deteriorated.

Further, by using this lamp, it is possible to provide a highly efficient display device such as a backlight device and a lamp device such as a lighting fixture which can be miniaturized.

[Brief description of drawings]

FIG. 1 is a partial sectional front view showing an embodiment of a discharge lamp of the present invention.

FIG. 2 is an enlarged front cross-sectional view showing a mount portion of the lamp shown in FIG.

FIG. 3 is an enlarged side cross-sectional view of the lamp of FIG. 1 as viewed in the direction of the arrow from a portion crossing along line XX.

FIG. 4 is a partially sectional front view showing an enlarged embodiment of another mount portion of the present invention.

FIG. 5 is an enlarged view of another embodiment of the mount portion of the present invention, (a) is a front view and (b) is a side view.

FIG. 6 is an enlarged front view showing a mount portion according to another embodiment of the present invention.

FIG. 7 is an exploded perspective view showing an embodiment of a backlight device according to the present invention.

[Explanation of Codes] L: Lamp 1: Glass Bulb 2: Sealing Part 3, 32, 33, 34: Mount 5: Sealing Wire 6, 62, 63, 64: Discharge Electrode 7: External Lead Wire 8, 83: Mercury emitting metal 9, 93, 94: Getter D: Light diffusing plate P: Display plate R: Reflecting mirror

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication H01J 61/36 A

Claims (8)

[Claims] 1. A discharge lamp comprising a glass bulb; a discharge sustaining medium enclosed in the glass bulb; a mount provided with a discharge electrode disposed in the bulb; wherein the mount forms an enclosed substance. A discharge lamp characterized in that the discharge electrode is connected to a sealing wire. 2. The discharge lamp according to claim 1, wherein the sealing wire forming the mount has a larger diameter than the external lead wire connected to the sealing wire. 3. The discharge electrode constituting the mount is a cylindrical sleeve, and the encapsulating material formed on the sleeve is at least one of a mercury emitting metal, an electron emissive material and a getter. Alternatively, the discharge lamp according to claim 2. 4. The discharge lamp according to claim 3, wherein the filling material filled in the discharge electrode formed of the cylindrical sleeve is at least one of a mercury-releasing metal, an electron emissive material, and a getter. 5. The discharge electrode formed of the tubular sleeve is filled with a mercury-releasing metal, and a getter is formed on the outer surface thereof. Discharge lamp. 6. The discharge electrode constituting the mount is a plate-shaped body or a rod-shaped body, and an encapsulating material formed on the plate-shaped body or the rod-shaped body is at least one of a mercury-releasing metal, an electron-emitting substance, and a getter. The discharge lamp according to claim 1, wherein: 7. The discharge lamp according to claim 1, wherein the glass bulb has an outer diameter of 10 mm or less. 8. A lamp device equipped with the discharge lamp according to any one of claims 1 to 7.