JP2009117156A - Flash lamp - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flash lamp having a getter comprising the vapor deposition film of an evaporation type getter material, wherein although a sufficient size of the vapor deposition region of the getter material is secured, discharge plasma created by discharge plasma or discharge never reaches a space where the getter is disposed, the expected function of the getter can be surely obtained, and also an arc tube is surely prevented from blackening. <P>SOLUTION: In this flash lamp, an arc tube made of a silica glass is provided and it has a discharge space in its inside, a pair of electrodes are disposed at both end parts in the inside of the arc tube, and the getter comprising the vapor deposition film of the evaporation type getter material is provided in the inner surface of the arc tube positioned in the back of the electrodes. A narrow portion is formed between a space where the getter is provided and the discharge space in the arc tube. This flash lamp is useful when lighting operation in which sparkling is continuously performed prescribed number of times is intermittently carried out. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to a flash lamp, and more particularly, to a flash lamp that is suitably used for curing a photocurable resin for bonding two disk pieces, for example, in the manufacture of an optical disk (DVD).

  Currently, for example, in a bonding process of disk pieces in the manufacture of a DVD (Digital Versatile Disk), a photocurable resin for bonding applied between two disk pieces on which one or both of them has an information recording film formed In addition, the photocurable resin is cured by irradiating light through the disk piece, and thereby, the two disk pieces are bonded together.

In the light source used for such a process, the intensity of light sufficient to cure the photocurable resin passes through the information recording film formed of a metal vapor deposition film such as aluminum formed on the disk piece. Because it is capable of irradiating high light and the base of the disk piece is made of a resin such as polycarbonate and is likely to be deformed by heat, it does not cause deformation due to heating of the disk piece. It is required to be a thing.
Therefore, as the light source, a flash lamp that can radiate light with very high intensity, for example, ultraviolet rays instantaneously and has little heat radiation, is preferably used.

  As a light irradiation device using such a flash lamp or a flash lamp, there have been proposed various configurations so far (see Patent Documents 1 to 3).

FIG. 7 is a plan view schematically showing a configuration of an example of a conventional flash lamp, and FIG. 8 is a side view showing a part of the flash lamp shown in FIG.
The flash lamp 30 has a light emitting part 32 formed to form a spiral shape on the same plane, and end regions continuous to both ends of the light emitting part 32 perpendicular to the plane including the light emitting part 32. The arc tube 31 has a leg portion 33 that is bent in the direction and has a discharge space S1 inside.
An electrode 40 made of molybdenum containing, for example, a trace amount of barium aluminate as an emitter material is disposed inside the leg portion 33 of the arc tube 31, and an electrode rod 41 having the electrode 40 at the tip thereof is a leg portion. It extends along the tube axis 33 and extends outwardly from the outer end surface of the arc tube 31, and is hermetically welded at the end of the arc tube 31 to form a sealing portion 34. .

In the flash lamp 30, a getter 46 having a function of adsorbing impure gas and maintaining the gas inside the arc tube 31 in a clean state is disposed in the space behind the electrode in the arc tube 31. ing.
The getter 46 evaporates when the evaporating getter material carried on the getter capsule 45 fixed on the outer peripheral surface of the electrode rod is heated in the manufacturing stage of the lamp. It is formed and formed in a film shape in a state where it is deposited to form a clean deposition surface. The getter 46 made of the evaporable getter material has a feature that the surface area is large and the operation efficiency of the getter 46 is good.

  Therefore, in the flash lamp used for the curing treatment of the photocurable resin, it is necessary to configure the electrode as having a smaller heat capacity than that used for other applications for the following reasons.

In the disk element laminating step, the flash lamp, for example, as shown in FIG. 9, the curing process of the photo-curing resin for bonding related to the preceding work, for example, flashes 10 times in 1 second. After being performed under continuous conditions, when the curing process of the photocurable resin for bonding related to the subsequent workpiece is performed, specifically, during the time until the subsequent workpiece is set, For example, it is in a rest state for 1.2 seconds.
Thus, when used for laminating disc elements, the flash lamp is not continuously pulsed, but is used in a state having a rest period, so that the electrodes are cooled during the rest period. Therefore, the first or second flash emission after the pause is performed in a state where the electrode temperature is insufficient, and the consumption of the electrode becomes severe. As a result, when the life of the lamp is shortened, there is a problem that mis-light emission is likely to occur and the arc tube is blackened to cause light emission. For example, miss light emission occurs at a high frequency of 4 pulses out of 10 pulses.
Therefore, in order to improve the startability of the lamp, it is necessary to configure the electrode to be warmed up early by making the electrode have a small heat capacity, for example, a diameter of φ3.5 mm.

Japanese translation of PCT publication No. 2002-528846 JP 2001-185088 A JP 09-193249 A

However, when the electrode diameter is made small as described above, the gap between the electrode and the inner wall of the arc tube becomes excessive, and the discharge plasma generated by the discharge of the flash lamp passes through the side of the electrode. As a result, the getter is heated and the function of the getter is lowered.
Further, when the getter material is exposed to the discharge plasma generated by the discharge along with the sputtering of the electrode, the getter material also generates spatter, leading to a situation where the light emitting region of the arc tube is blackened early.
On the other hand, if the tube diameter of the leg of the arc tube where the electrode is located is made smaller along with the reduction of the electrode, the evaporation area of the evaporative getter material cannot be gained, so the expected getter function Cannot be obtained.

  The present invention has been made on the basis of the above circumstances, and in a flash lamp having a getter configured in a film shape by evaporating an getter material of evaporation type, vapor deposition of a sufficiently large getter is performed. Although the area is secured, the discharge plasma does not reach the space where the getter is arranged, so that the desired getter function can be obtained reliably, and the arc tube is black. An object of the present invention is to provide a flash lamp capable of preventing the occurrence of crystallization.

The flash lamp of the present invention includes an arc tube made of quartz glass having a discharge space inside, and a pair of electrodes are arranged at both ends inside the arc tube, and an arc tube positioned behind the electrodes. A flash lamp having an inner surface provided with a getter made of a vapor deposition film of an evaporation type getter material,
The arc tube has a narrow portion formed between a space provided with a getter and a discharge space.

In the flash lamp of the present invention, it is preferable that the narrow portion is formed at a position located around the electrode.
The flash lamp of the present invention is useful when it is used so that a lighting operation in which flash emission is continuously performed a predetermined number of times is performed intermittently.

  According to the flash lamp of the present invention, the narrow portion is formed in the arc tube between the space where the getter is disposed and the discharge space, so that the evaporation type getter material has a sufficient size. While the deposition area is ensured, the gap between the outer peripheral surface of the electrode and the inner peripheral surface of the arc tube can be made as small as possible and generated in the discharge space. Since it is possible to prevent the discharge plasma from entering the space in which the getter is disposed, it is possible to reliably prevent the getter from being sputtered, and thus to reliably obtain the intended getter function. In addition, it is possible to reliably prevent the problem that the light emitting portion region is blackened early due to the getter being sputtered.

In addition, since the separation distance between the outer peripheral surface of the electrode and the inner peripheral surface of the arc tube is small, the discharge plasma does not reach the rear portion of the electrode, and the discharge is generated at the tip of the electrode. As a result of efficient heating of the tip, the temperature rise after the pause is fast, and excellent lamp startability can be maintained for a long period of time, and the electrode is also less sputtered, Blackening of the light emitting portion region due to this can also be suppressed.
Therefore, it is extremely useful when the lighting operation in which the flash emission is continuously performed a predetermined number of times is used to be performed intermittently.

1 is a perspective view showing a configuration of an example of a flash lamp according to the present invention, FIG. 2 is a side view showing a part of the flash lamp shown in FIG. 1, and FIG. 3 is a broken line in FIG. It is an expanded sectional view which shows the structure of the area | region enclosed.
The flash lamp 10 is preferably used for a curing process of a photo-curing resin for bonding in a process of bonding two disk-shaped disk pieces in DVD manufacturing, for example, and is a cylindrical arc tube forming material Are formed so as to form a spiral shape on the same plane, and end regions continuous to both ends of the light emitting unit 12 are bent in a direction perpendicular to the plane including the light emitting unit 12. And a light emitting tube 11 made of quartz glass having a discharge space S1 therein.
Inside the arc tube 11, one or more of rare gases xenon, krypton, and argon are sealed, and light in a wavelength region of, for example, 200 to 1100 nm is emitted.

  The legs 13 of the arc tube 11 are located at the inner edge side position and the outer edge side position of the light emitting part region, respectively, and the inside of each leg part 13 contains, for example, a small amount of barium aluminate as an emitter material. A substantially cylindrical electrode 20 made of molybdenum is disposed, and an electrode rod 21 having the electrode 20 at its tip extends along the tube axis of the leg portion 13 and extends outward from the outer end surface of the arc tube 11. It is disposed so as to protrude and is hermetically welded at the end of the arc tube 11 to form a sealing portion 14 having a so-called rod seal structure. Here, the diameter of the electrode 20 is, for example, φ3 to φ4 mm.

  In the space behind the electrode 20 in the arc tube 11, that is, in the space on the sealing portion 14 side, a ring-shaped getter capsule 25 made of, for example, nickel carrying an evaporative getter material is provided on the outer peripheral surface of the electrode rod 21. Further, a getter 26 made of a vapor deposition film in which a getter material is formed into a film by vapor deposition is provided on the inner surface of the arc tube 11 around the getter capsule 25. Here, examples of the getter material include barium.

Thus, in the flash lamp 10 configured as described above, the space (hereinafter referred to as “getter arrangement space”) S2 in which the getter 26 is provided and the getter capsule 25 is arranged in the arc tube 11 and the discharge space S1. A narrow portion is formed at a position between the two.
In the flash lamp 10, the entire front end surface of the electrode 20 is disposed so as not to hinder the start of discharge at a location located around the electrode 20, specifically, at a location corresponding to the axial length portion of the electrode 20. In the exposed state, the tube diameter of the arc tube 11 is reduced to form a reduced diameter portion 18, thereby forming a narrow portion.
The reduced diameter portion 18 (narrow portion) is formed in a state where the size of the annular gap formed between the inner peripheral surface of the arc tube 11 and the outer peripheral surface of the electrode 20 is, for example, 1 to 2 mm. Is preferred.

  As described above, the flash lamp 10 is preferably used for a curing process of a photo-curing resin for bonding in a bonding process of two disc-shaped disk pieces in DVD manufacturing, for example. The flash lamp 10 is used by intermittently performing a lighting operation in which one predetermined cycle of flash emission is one cycle (see FIG. 9). Note that the lighting conditions of the flash lamp 10, such as the pulse width and current density, and the length of the pause period can be changed as appropriate according to the purpose.

Thus, according to the flash lamp 10 having the above-described configuration, basically, the electrode 20 has a relatively small diameter and a small heat capacity even when used in the lighting method as described above. By being configured, the electrode 20 is likely to be warmed (the rising speed of the electrode temperature is increased), so that excellent startability of the lamp can be maintained for a long period of time, and the electrode 20 is consumed during re-lighting. Therefore, the occurrence frequency of miss light emission at the end of the lamp life can be reduced.
In addition, since the narrowed portion is formed by forming the reduced diameter portion 18 at a position between the getter arrangement space S2 and the discharge space S1 of the arc tube 11, a sufficiently large vapor deposition region of the getter material is formed. However, if the arc tube 11 is a straight tube, the outer peripheral surface of the electrode 20 and the inner peripheral surface of the arc tube 11 that increase as the electrode 20 is made smaller are provided. Since the annular air gap between them can be made as small as possible and the discharge plasma generated in the discharge space S1 can be prevented from entering the getter arrangement space S2. 26 and the getter capsule 25 can be reliably prevented from being sputtered. Therefore, the intended function of the getter 26 (impurity gas adsorption ability) can be reliably obtained, and the getter 26 can be obtained. Emitting region due to the sputtering is blackened early, it is possible to reliably prevent the problem arises that.

  Further, since the separation distance between the outer peripheral surface of the electrode 20 and the inner peripheral surface of the arc tube 11 is small, the discharge plasma does not reach the rear portion of the electrode 20 and the discharge is exposed to the discharge space S1. Since they are generated at the tip, the tip of the electrode 20 is efficiently heated. As a result, the temperature rise after the stop increases and excellent lamp startability can be maintained for a long period of time. As described above, as a result of the tip portion of the electrode 20 being heated well, the occurrence of spatter from the electrode 20 is also reduced, and the blackening of the light emitting region caused by the sputter of the electrode 20 can be suppressed. .

Hereinafter, experimental examples performed for confirming the effects of the present invention will be described.
<Experimental example 1>
A flash lamp according to the present invention was manufactured according to the configuration shown in FIGS. 1 to 3, and a comparative flash lamp having the same configuration except that the arc tube did not have a narrow portion.
[Flash lamp configuration]
Arc tube: light emitting part: outer diameter φ10.5 mm, inner diameter φ8.5 mm, leg part: outer diameter φ10.5 mm, inner diameter φ8.5 mm, narrow part (reduced diameter part); outer diameter φ8 mm, inner diameter φ6 mm, total length 5 mm,
Filled gas (rare gas): Xenon, filled pressure (static pressure); 40 kPa
Electrode: outer diameter φ3.5 mm, total length 5 mm, material: main material Mo (molybdenum),
Getter material: Barium,
Getter capsule: material; nickel, shape; ring-shaped one having a weight (amount of getter material) of 1 mg, arrangement position; a position spaced 20 mm axially outward from the rear end of the electrode,
Film-shaped getter formation region (deposition region of getter material); in the region of about 20 mm in length from the rear end of the electrode about 10 mm axially outward to the axially outward side of the inner surface of the arc tube Formed all around.

For each of the flash lamps, a lighting operation in which flash light emission is continuously performed 10 times during a time of 1 second is performed at a time interval of 1.2 seconds (pause) under the condition that the light emission energy in one flash light emission is 200 J. A lighting test was performed intermittently every period.
Then, the illuminance of ultraviolet light having a wavelength of 365 nm was measured every predetermined number of times of lighting (lighting cycle), and the illuminance maintenance rate when the illuminance by the first flash emission was 100% was examined. The results are shown in FIG.
The illuminance measurement was performed by placing the flash lamp in a state where it was incorporated in a mirror, and measuring the ultraviolet light emitted from the flash lamp with an illuminometer placed 30 cm away from the flash lamp. .

  According to the flash lamp according to the present invention, as shown by the curve (a) in FIG. 4, even when 10 million flash emission (1 million cycles), which is the target life, is performed, 80% While the above illuminance is maintained, the flash lamp for comparison emits flash light (400,000 cycles) with an illuminance maintenance ratio of 4 million times as shown by the curve (b) in FIG. At that time, it was confirmed that the brightness decreased to 60% or less, which is the life standard of the illuminance maintenance rate. This is because the discharge plasma generated by the discharge enters the getter arrangement space, so that getter sputtering occurs, the function of the getter itself deteriorates and the wall surface of the arc tube is stained. Conceivable.

As mentioned above, although embodiment of this invention was described, this invention is not limited to said embodiment, A various change can be added.
For example, in the present invention, it is sufficient that a narrow portion is formed at a position between the discharge space and the getter arrangement space in the arc tube, and the means for forming the narrow portion reduces the tube diameter of the arc tube. For example, as shown in FIG. 5, the ring-shaped member 19 may be provided in the arc tube 31.
Further, the narrow portion may be formed at a position on the rear side from the rear end of the electrode 20 as shown in FIG. 6, for example. In the case of such a configuration, the distance d between the rear end edge of the electrode 20 and the front end edge of the reduced diameter portion 18 of the arc tube 11 may be set to, for example, 1 to 2 mm.
Further, the shape of the lamp (arc tube) and other specific configurations are not limited to those of the above-described embodiment.

It is a perspective view which shows roughly the structure in an example of the flash lamp of this invention. It is a side view shown in the state where a part of flash lamp shown in FIG. 1 was broken. It is an expanded sectional view which shows the structure of the area | region enclosed with the broken line in FIG. It is a figure which shows the illumination intensity maintenance factor of the flash lamp produced in the experiment example. It is sectional drawing which shows schematically the structure of the principal part in the other example of the flash lamp of this invention. It is sectional drawing which shows schematically the structure of the principal part in the further another example of the flash lamp of this invention. It is a top view which shows roughly the structure in an example of the conventional flash lamp. It is a side view shown in the state where a part of flash lamp shown in FIG. 7 was broken. It is a figure which shows an example of the lighting method of a filament lamp when used for the resin hardening process in a disk material bonding process with the temperature change of an electrode.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Flash lamp 11 Light emission tube 12 Light emission part 13 Leg part 14 Sealing part 18 Reduced diameter part 19 Ring-shaped member 20 Electrode 21 Electrode rod 25 Getter capsule 26 Getter S1 Discharge space S2 Getter arrangement space 30 Flash lamp 31 Light emission tube 32 Light emission part 33 Leg part 34 Sealing part 40 Electrode 41 Electrode rod 45 Getter capsule 46 Getter

Claims (3)

An arc tube made of quartz glass having a discharge space inside, a pair of electrodes disposed at both ends inside the arc tube, and an evaporation type getter on the inner surface of the arc tube positioned behind the electrodes A flash lamp provided with a getter made of a deposited film of material,
A flash lamp characterized in that a narrow portion is formed in the arc tube between a space provided with a getter and a discharge space.   The flash lamp according to claim 1, wherein the narrow portion is formed at a position positioned around the electrode.   The flash lamp according to claim 1 or 2, wherein the flash lamp is used so that a lighting operation in which flash emission is continuously performed a predetermined number of times is intermittently performed.

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