KR20110035878A

KR20110035878A - Long arc type discharge lamp

Info

Publication number: KR20110035878A
Application number: KR1020100086979A
Authority: KR
Inventors: 가즈유키 모리
Original assignee: 우시오덴키 가부시키가이샤
Priority date: 2009-09-29
Filing date: 2010-09-06
Publication date: 2011-04-06
Also published as: JP2011076724A; TWI466166B; KR101313456B1; TW201112308A; CN102034673B; JP5347875B2; CN102034673A

Abstract

PURPOSE: A long arc-shape discharge lamp is provided to prevent the outflow of inner material since both ends inside an arc tube are sealed by a foil seal structure. CONSTITUTION: A long arc-shape lamp comprises a sealing portion(3) formed on both ends of an arc tube(2) made of quartz glasses. A pair of electrodes(4) faces each other inside the arc tube. The backend of the non-emitting space of the electrode is formed into a flat shape. A quartz glass portion(6) is installed at the rear end of the long arc-shape lamp into a flat shape. An outer lead(7) is projected from the outside of the arc tube.

Description

Long arc type discharge lamp {LONG ARC TYPE DISCHARGE LAMP}

The present invention relates to a long arc discharge lamp, and more particularly, to a long arc discharge lamp in which a metal of mercury or mercury thereof, halogen is sealed, and both ends are sealed by a thin seal structure. will be.

Conventionally, metals other than mercury or mercury, and halogen-enclosed long arc type discharge lamps such as metal hydride lamps are discharge lamps that emit ultraviolet rays, for example, resins, adhesives, inks and photoresists. It is widely used for the use of various processes, such as hardening, drying, melting, or softening.

Such a long arc discharge lamp generally has a structure in which a light tube made of quartz glass and a sealing portion at both ends thereof are formed, a metal foil is embedded in the sealing portion, and an electrode made of tungsten is connected to the metal foil. to be.

Although there are various kinds of sealing part structures, it is known to embed a plate-like or flat glass member in this sealing part and seal it using this glass member.

In this structure, the rear end of the sealing portion side of the electrode is formed flat, and a plate-like or flat glass member is provided on the rear end side thereof, and the metal foil is joined to the upper and lower surfaces of the flat portion of the electrode, and the upper and lower surfaces of the glass member are It extends to and joins with an external lead in the rear end.

Japanese Laid-Open Patent Publication No. 2006-134710 discloses a long arc discharge lamp having such a structure, in which a predetermined amount of rare gas, halogen, mercury, and iron are enclosed in the light emitting tube. At the time of lighting, ultraviolet-ray of wavelength 365nm vicinity can mainly be irradiated.

And this patent document describes invention which forms the small diameter site | part in the eastern part of an electrode, and prevents the halogen from solidifying on the sealing part side.

By the way, in such a long arc discharge lamp, as mentioned above, since the distance from an arc becomes large in the vicinity of a sealing part, compared with a light emitting part, temperature is low and it is not easy to collect halogen. In addition, this type of lamp generally has a higher operating pressure than atmospheric pressure, and the halogen is likely to enter the sealing portion.

Although the temperature of the molybdenum foil of a sealing part changes with lamp design and cooling conditions, it is at least 500 degreeC or more, and the reaction of molybdenum and a halogen progresses, and the metal foil which consists of molybdenum of a sealing member is not enough. Erosion and the interface between molybdenum and quartz glass are peeled off from the glass by high pressure, so-called "thin-lifting" phenomenon occurs. In addition, if the thinning of the foil proceeds, an undesired phenomenon occurs such that finally, the inclusions in the lamp leak (leak) to the outside, and the mercury inside leaks.

The cause of such leakage is mainly due to the operating pressure at the time of lighting. For the light emission length of 50 cm or more in this type of long arc discharge lamp, since the lamp input is 80 W / cm or more, it becomes a high input lamp of at least 4 mW or more. Therefore, at the time of lighting, the enclosure fully evaporates and operates, and the operating pressure is at least 1 atm or more, corresponding to what is called a high pressure discharge lamp. In these lamps, this operating pressure is always applied to the sealing portion during lighting.

Japanese Patent Publication No. 2006-134710

SUMMARY OF THE INVENTION In view of the problems of the prior art, the present invention is a long arc discharge lamp in which a pair of electrodes are disposed opposite to each other in the light emitting tube, and the light emitting tube is sealed by a thin seal structure at both ends. It is an object of the present invention to provide a long arc discharge lamp in which one halogen enters the sealing portion to erode the metal foil, or the foil is generated by the halogen so that the inclusions do not leak out.

In order to solve the said subject, in the long arc discharge lamp which concerns on this invention, electric potential hardness is 8 V / cm or less, lamp input electric power is 80 W / cm or more, light emission length is 50 cm or more, and an enclosure is mercury Or a combination of a metal other than mercury and halogen, and having a radiation of light having a wavelength of 450 nm or less, characterized in that the operating pressure at the time of lighting becomes a negative pressure.

More preferably, the potential hardness is 8 V / cm or less, the operating pressure at the time of lighting is 50 kPa or less, and the foil seal structure is characterized by being a foil composed of two sheets.

According to the present invention, since the operating pressure at the time of lighting becomes a negative pressure of less than 1 atm while being a high input to the long arc discharge lamp, the inclusions in the light emitting tube, in particular, halogen do not penetrate into the sealing portion, and therefore corrosion of the metal foil is prevented. There is no effect, and no lifting of the foil occurs or the inclusions do not leak out. As a result, the life of the lamp is extended.

By the way, in order to make the operating pressure into a negative pressure, it is necessary to set a small amount of encapsulation of mercury or the like, which causes the potential hardness (voltage) to be lowered and the current increases. When the lamp current increases, it is necessary to increase the thickness of the foil or to increase the width in order to increase the current capacity of the molybdenum foil.

As a method of increasing the current capacity, there is also a method of increasing the number of molybdenum foils. However, the method of increasing the longevity of the molybdenum foil increases the welding point of the molybdenum foil and the electrode, it is necessary to put a glass member between the molybdenum foil, the small space generated around the electrode becomes large, and halogen penetrates the space It becomes easy to do it and is easy to cause foil lifting. Therefore, the structure of two or more foils is mainly used by the xenon lamp which does not contain a halogen, and the ultra-high pressure mercury lamp of a short arc, and the halogen-containing lamp normally sealed with one molybdenum foil.

On the other hand, in the present invention, as described above, even when the inside of the light emitting tube is turned on, it is negative pressure, and the structure of two or more strips can be adopted from the advantage that thinning in the sealing portion is less likely to occur than a normal high-pressure discharge lamp. Therefore, it is possible to actively cope with the increase of the current capacity.

1 is an overall view of a long arc discharge lamp according to the present invention.
2 is a partial cross-sectional view of FIG. 1.
3 is a view showing various lamps provided for the experiment.
4 is a graph illustrating illuminance retention rates of various lamps of FIG. 3.

Fig. 1 shows a long arc discharge lamp of this invention, and Fig. 2 is an enlarged view of the main part thereof. In the figure, the long arc lamp 1 has sealing parts 3 at both ends of the light emitting tube 2 made of quartz glass, and the pair of electrodes 4, 4) are arranged opposite each other at a predetermined distance, for example, 500 mm.

In this embodiment, the rear end 4a of the non-light-emitting space side of the electrode 4 is formed in a flat shape, and in the rear end thereof, the quartz has a flat shape in accordance with the shape of the rear end 4a of the electrode. The glass member 6 is provided.

In the sealing part 3, the two pieces of metal foils 5 and 5 joined to the upper and lower surfaces of the flat rear end 4a of the said electrode 4 by welding etc. extend along the upper and lower surfaces of the glass member 6, and It is connected to the external lead 7 at the rear end. The outer lead 7 protrudes out of the light emitting tube 2 and is connected to a feeder line (not shown).

In the light emitting tube 2, a predetermined rare gas, halogen, mercury, and iron are encapsulated. In this example, at the time of lighting, for example, ultraviolet light is emitted mainly at a wavelength of around 365 nm.

Incidentally, the inclusions are not limited to the above, and any combination of A: mercury or metal + B: halogen other than mercury may be used.

Examples of these combinations include the following.

Hg <mercury> + (I <iodine> Br <bromine>)

Zn (zinc) + (I, Br)

Zn + FeI ₂ 〈Iron Iodide〉

Hg + FeI ₂

Metal α (Bi <bismuth>, Sb <antimony>) + (I, Br)

These light emitting materials are encapsulated so that the potential hardness of the lamp is 8 V / cm or less.

Moreover, xenon is enclosed, for example as a rare gas for improving startability.

The light emission length determined by the distance between the electrodes is 500 mm or more, and the lamp input power is 80 W / cm or more.

The lamp which enclosed the said luminescent substance mainly radiates the ultraviolet-ray of wavelength 340-450 nm, As the use, For example, hardening of resin, an adhesive agent, an ink, a photoresist, drying, melting, or softening, It is used for various processing such as

An experimental example is shown below.

3 shows various long arc-type discharge lamps provided for the experiment, and the lamps have a common shape, dimensions, sealing structure, light emission length, and the like. The pressure is different.

The lamp shown in Example 1 was sealed so that the sealing pressure of 130 mg of mercury, 10 mg of mercury iodide, and xenon gas might be set to 8 kPa using a light emitting tube having an inner diameter of 22 mm and an internal content of 400 cm 3, It is a discharge lamp in which the electrode 4 is arrange | positioned at the distance between electrodes of 1,000 mm, and is rated point force of 16,000 W, and lamp voltage of 795 V.

The lamp shown in Example 2 was sealed so that the sealing pressure of 73 mg of mercury, 2 mg of mercury iodide, and xenon gas became 4 kPa using the inner tube of the center part and the internal volume of the same light emitting tube as the lamp of Example 1, The lamp having a rated point force of 16,000W as in Example 1, but the lamp voltage is 585V.

The lamp shown in the prior art was carried out in which the inner diameter of the center portion and the inner volume thereof were sealed using the same light emitting tube as in the lamp of Example 1, and the sealing pressure of 825 mg of mercury, 2 mg of mercury iodide and xenon gas was 4 kPa. A lamp with a rated point power of 16,000W, as in Example 1, but with a lamp voltage of 1357V.

And while the potential hardness of the lamp of the said prior art example is 13.6 (V / cm), the potential hardness is 7.95 (V / cm) in the lamp of Example 1 of this invention, and 5.85 (V / cm) in the lamp of Example 2 Cm).

In contrast to this, if the operating pressure of each lamp is verified, the pressures of mercury, iodine and xenon when the average gas temperature inside the lamp is 2,000 K,

"Gas State Equation": P = nRT / V

Where P is the operating pressure, n is the number of moles, R is the gas constant, T is the absolute temperature = the average gas temperature,

V: Lamp Contents

It calculated | required and totaled them, and calculated | required operating pressure.

The operating pressure obtained in this way is 1.90 (atm) in the conventional example, while it is 0.81 (atm) in Example 1 and 0.41 (atm) in Example 2 of the present invention. It turns out that the negative pressure remains in the lit state.

Fig. 4 is a graph showing the illuminance retention rate after the life lighting tests of the lamps are performed. The vertical axis represents illuminance retention (%) with respect to the initial illuminance, and the horizontal axis represents the elapsed lighting time.

From the test results, while the lamps were turned on, the illuminance decreased substantially at the same lighting time. However, although the lamp of the prior art first linked from the sealing part about 4,500 hours of lighting time, Example 1, 2 continued lighting while deteriorating illuminance after that. In particular, Example 2 maintained lighting over 8,000 hours. In the lamp of Example 2, since the breakdown voltage of the lamp at the time of lighting is lower, it is considered that the progress of foil lifting is delayed. At the time of linking, at the same time as leaking, the atmosphere flowed into the lamp, and the lighting became impossible to turn on, and almost no leakage of the encapsulation to the outside was observed.

These problems are caused by the operating pressure at the time of the lighting of the lamp containing the halogen, irrespective of the presence or absence of mercury, and the same tendency can be seen even when halogen and other metals are added.

As described above, even in a lamp having the same light emitting tube shape and the sealing part structure, in the lamp of the present invention in which the operating pressure becomes a negative pressure less than atmospheric pressure with respect to a conventional lamp in which the operating pressure in the light emitting tube is equal to or higher than atmospheric pressure, the sealing portion It is understood that the occurrence of the leak of the encapsulating substance in Esau has been suppressed for a long time, and a great long life is achieved.

1: long arc discharge lamp
2: light emitting tube
3: sealing part
4: electrode
4a: rear end of flat electrode
5: metal foil
6: glass member
7: external lead

Claims

In a long arc discharge lamp in which a pair of electrodes are disposed opposite to each other in a light emitting tube, and the light emitting tube is sealed by a thin seal structure at both ends thereof.
The potential hardness is 8 V / cm or less, the lamp input power is 80 W / cm or more, the emission length is 50 cm or more, and the inclusion is a combination of mercury or a metal other than mercury and halogen, and emits light having a wavelength of 450 nm or less. And the operating pressure at the time of lighting becomes a negative pressure, The long arc discharge lamp characterized by the above-mentioned.

The method according to claim 1,
A long arc discharge lamp, characterized in that the operating pressure at the time of the lighting is 50 kPa or less.

The method according to claim 1,
Long arc-type discharge lamp, characterized in that the foil seal structure is a foil consisting of two pieces.