JP2001332217A - Light source - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light source that can extend the lifetime of a discharge tube. SOLUTION: In this light source, a radiator is made to contact with a head-on discharge lamp. The radiator is kept in contact with a peripheral region 1ws of the light exit window 1ww. The radiator is equipped with a radiator block 101 bl', that has direct contact with the peripheral region 1ws, and quantity of substance that deposits on the light exit window 1ww can be reduced to prolong life of the discharge tube because substances produced by sputtering of electrodes in the discharge tube largely deposit on the peripheral region 1ws.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a lamp having a discharge tube, such as a deuterium lamp or a xenon flash lamp.

[0002]

2. Description of the Related Art Lamps utilizing microwaves are disclosed in
No. 182910. The lamp described in this publication encloses a gas in a container and irradiates the gas with microwaves to excite the gas to generate light. The gas contains a fluorine-based gas, and the fluorine-based gas etches the inner surface of the quartz glass container, and Si impurities generated by the etching adhere to the inner surface of the container. Therefore, in the lamp described in the publication, a cooling pipe is penetrated into the container to adsorb impurities generated by etching with fluorine gas.

[0003]

On the other hand, a discharge tube utilizing an arc discharge between electrodes has been conventionally known. Such discharge tubes are known. As a head-on type discharge tube, a deuterium lamp, a xenon flash lamp, and the like are known. A head-on type discharge tube encloses a gas such as deuterium or xenon in a container having a cylindrical side wall, and emits light emitted from the gas between the electrodes by discharging between a pair of electrodes arranged inside the container. The light is output to the outside via a light exit window located at the top of the container.

[0004] Such a discharge tube uses a discharge between the electrodes, so that it is not necessary to use a fluorine-based gas. Therefore, there is no etching of the container, and it is unlikely that impurities adhere to the inner surface of the container. I could not imagine.

[0005] However, even in a discharge tube such as a deuterium lamp or a xenon flash lamp, the output light intensity is reduced by prolonged use. This was initially thought to be due to the deterioration of the cathode. Of course, the cathode deteriorates with prolonged use, but the present inventors have found that the major cause of the decrease in light output is not the deterioration of the cathode. In other words, it has been found that the decrease in light output is due to the fact that the substance released into the container due to the sputtering of the cathode and the like accompanying the discharge between the electrodes in the discharge tube adheres to the light exit window of the container. Obtained. The present invention is based on such knowledge, and has an object to provide a light source capable of extending the life of a discharge tube.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and a light source according to the present invention has a structure in which a gas is sealed in a container and a discharge between a pair of electrodes arranged in the container. A discharge tube for outputting the light emitted from the gas between the electrodes to the outside through a light exit window located at the top of the container, and having a radiator contact the surface of the peripheral area of the light exit window. It is characterized by.

According to this light source, light emission is output to the outside through the light exit window, but the peripheral area is cooled by the heat dissipating member in contact with the surface of the peripheral area of the light exit window. Therefore, a large amount of substances generated by sputtering of a pair of electrodes constituting the cathode or the anode adhere to the peripheral region, and the amount of the substance adhered to the light exit window decreases.

[0008] The radiator is preferably in contact with the container such that the peripheral area is at least at the top of the container. In this case, since the light exit window and the peripheral region are both located at the top of the container, the attachment of the substance to the light exit window can be efficiently suppressed.

Preferably, the radiator is in contact with the container such that the peripheral region is also located on the side wall of the container. In this case, since the side wall is also cooled, the attachment of the substance to the light exit window can be more efficiently suppressed. Also, if the radiator is also in contact with the top and side walls as a unit,
A radiator can be placed on the top of the container, and the movement of the radiator in a direction perpendicular to the tube axis of the discharge tube can be restricted by the contact surface of the radiator with the side wall.

The discharge tube has a stem that forms the bottom of the vessel, and the stem and the radiator are fixed via a plurality of bolts extending parallel to the tube axis. In this case, since the stem is used for fixing the radiator, an increase in the number of components required for fixing can be suppressed.

In the case where the heat radiator is set on the side wall surface of the discharge tube so that the peripheral region surrounds the tube axis of the discharge tube,
Cooling can be performed so as to surround the side wall, and when the heat radiator integrally surrounds the side wall, movement of the heat radiator in a direction perpendicular to the tube axis can be restricted.

One of the electrodes is a cathode made of a filament, and the other is an anode for collecting thermoelectrons generated by energizing the filament. When the gas sealed in the container contains deuterium, The discharge tube functions as a deuterium lamp. A deuterium lamp has a low temperature rise on the lamp surface, unlike a xenon lamp in which high-pressure xenon is sealed. In such a lamp, the temperature difference between the cooling region and the non-cooling region by the radiator becomes smaller than that of the xenon lamp, so that deterioration of the container due to the temperature difference can be suppressed.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a light source according to an embodiment will be described. The same elements or elements having the same functions will be denoted by the same reference symbols, without redundant description. (First Embodiment) FIG. 1 is a longitudinal sectional view of a light source according to a first embodiment, FIG. 2 is a sectional view taken along line II-II of the light source shown in FIG. 1, and FIG. 3 is a main part of the light source shown in FIG. It is a perspective view of.

The light source of this embodiment includes an outer box 100, an inner box (radiator box) 101bx housed in the outer box 100,
A discharge tube 10 is provided inside the inner box 101bx. The discharge tube 10 is mounted on a socket SC fixed to the bottom plate of the inner box 101bx.
The outer surface of bx is cooled by an air cooling fan 102 provided on the side wall of the outer box 100. Air cooling fan 102
The air taken in from the outside flows to the outside through a vent 100bld formed in the side wall of the outer box 100.

The stability of the light output of the deuterium lamp is deteriorated due to the fluctuation of the outside air temperature.
Since the air is circulated between 01bx and the outer box 100 and the air circulating in the deuterium lamp is not directly applied, the stability of the output is not impaired.

The discharge tube 10 includes an airtight container (glass bulb) 1 having a cylindrical side wall 1w. A gas such as deuterium is sealed in the container 1 so as to emit ultraviolet light as output light, and is discharged from the gas between the electrodes 2c and 2a by a discharge between the pair of electrodes 2c and 2a arranged inside the container 1. The emitted light is output to the outside via a light exit window 1ww located at the top of the container 1.

A radiator made up of radiating blocks 101bl, 101bl 'and a radiating spring member 101sp is in contact with the surface of the peripheral region 1ws of the light exit window 1ww.
The discharge tube 10 is disposed in the heat radiating box 101bx and the outer box 100 for stable light emission. Heat radiator 101
The heat absorbed from the discharge tube 10 through bl ′, 101sp, and 101bl is efficiently radiated to the outside, and the peripheral region 1ws
Cooling efficiency is high.

Heat dissipating block 1 in direct contact with discharge tube 10
01bl 'is shaped to cover the top of the vessel 1 of the discharge tube 10. The outer surface of the top of the container 1 has a circular surface and a cylindrical side surface that is continuous with the outer periphery of the circular surface and extends about 20% or less of the length of the tube in a direction perpendicular to the circular surface. In a region of a predetermined radius from the center of the circular surface, a heat radiation block 1
01bl 'is not in contact with the light exit window 1
Functions as ww. That is, the center of the annular heat radiation block 101bl ′ is located at the center of the through hole 1 extending parallel to the tube axis.
01blo ', and the heat radiation block 101b
The end on the discharge tube side of the through hole 101blo 'located inside 1' abuts on the peripheral region of the circular surface, the diameter of which increases from the corresponding contact position to the diameter of the container, and is parallel to the tube axis. Extending.

The heat-dissipating spring member 101sp will be described in detail.
, A dislocation portion that stands upright and bent from both ends in the width direction of the flat portion toward the heat dissipation block 101bl, and a heat dissipating block 1 of the dislocation portion.
And a fixed portion bent so as to be wide at the position of contact with 01bl. The fixing portion of the spring member 101sp is fixed to the heat radiation block 101bl by bolts B1 and B2, and the heat radiation block 101bl is fixed to the bolt B1.
1, B12, B13 are fixed to the inner surface of the heat radiation box 101bx.

When no load is applied, the spring member 101sp slightly extends in a direction parallel to the tube axis. When the spring member 101sp is pressed against the heat radiation block 101bl 'along the tube axis, the spring member 101sp is elastically deformed. It is compressed and urges the heat radiation block 101bl '. Therefore, the degree of adhesion between the spring member 101sp and the heat radiation block 101bl 'is improved. The spring member 101sp has an opening 101spo through which light emitted from the discharge tube 10 passes.

The heat dissipating block 101bl has two parallel
An opening 101bl formed in these two planes
There is a through-hole 101blt for light passage that passes through the block 101bl so as to communicate between o. Therefore, the heat dissipation block 101bl is
It has an annular shape surrounding it. Further, the inner box 10
1bx has an opening 101bxo for light emission on the wall surface.

The spring member 101sp and the annular radiating block 101bl are respectively formed with openings 101spo and 101sp.
blo are fixed so as to overlap. Further, the heat dissipation block 101bl and the inner surface of the side wall of the inner box 101bx are fixed by bolts B11, B12, B13 such that the respective openings 101blo, 101bxo overlap. Note that these openings 101blo and 101bxo
Overlaps with an opening 100op provided in the side wall of the outer box 100.

According to the present light source, light emission is output to the outside of the discharge tube through the light emission window 1ww, and the opening 101bl
o ', 101spo, 101blo, 101bxo, 1
00 op, the light emission in the discharge tube 10
Is output to the outside. Since the heat radiator is in contact with the surface of the peripheral area 1ws of the light exit window 1ww, the peripheral area 1ws
Is cooled. Therefore, a large amount of the substance generated by sputtering of the cathode electrode 2c or the anode electrode 2a adheres to the peripheral region 1ws, and the amount of the substance adhered to the light exit window 1ww decreases. That is, since the light exit window 1ww is not contaminated for a long period of time, the life of the discharge tube can be extended.

Although the discharge tube 10 is conventionally known, this will be briefly described. In the container 1,
The two electrodes 2c and 2a are arranged as described above,
One of the electrodes is a cathode 2c made of a filament, and the other electrode is an anode 2a for collecting thermoelectrons generated by energizing the filament 2c. The filament 2c is disposed in a metallic shield body 3 surrounding the filament 2c. Thermions generated by the filament 2c are emitted in the direction of the focusing electrode 4, and the orbit is bent by the shielding body 3 and the focusing electrode 4. The light enters the anode 2a.

When the gas sealed in the container 1 contains deuterium, the discharge tube 10 functions as a deuterium lamp.
A deuterium lamp has a low temperature rise on the lamp surface, unlike a xenon lamp in which high-pressure xenon is sealed. In such a lamp, the temperature difference between the cooling region 1ws and the non-cooling region 1ww due to the radiator is smaller than that of the xenon lamp, so that the deterioration of the container 1 due to the temperature difference is suppressed.

The present invention can be applied to a xenon flash lamp or a mercury xenon lamp in which xenon is sealed in the container 1, and the electrode 2c need not be a filament.

As described above, as described above, the cathode electrode 2c
Alternatively, since a large amount of substances generated by sputtering of the anode electrode 2a adhere to the peripheral region 1ws, the light emitting window 1ww is not contaminated for a long time, and the life of the discharge tube can be prolonged.

Although the above-described discharge tube is disclosed as being of a vertical type, it may be used as a horizontal type. That is. The tube axis of the discharge tube 10 may be parallel to the vertical direction, or may be parallel to the horizontal direction. Also, the through hole 101bl
t, 101blo 'may be such that its diameter increases as the distance from the discharge tube 10 increases, or may be constant. These are the same in the following embodiments.

The above light source provided with a heat radiation block (Example)
, And a light source (comparative example) from which the light output was removed, the change over time of the relative light output was measured.

FIG. 4 shows the operating time (hour) of these light sources.
4 is a graph showing a relationship between the relative light output (measured wavelength: 250 nm). As can be seen from these graphs, the rate of decrease in the relative light output with the heat dissipation block is 5% or less even when the relative light output exceeds 100 hours, and the life is significantly prolonged compared to the case where the heat dissipation block is removed. Has been achieved. The numerical data is shown in Table 1 below.

[0031]

[Table 1] (Second Embodiment) FIG. 5 is a longitudinal sectional view of a light source according to a second embodiment, FIG. 6 is a sectional view taken along line VI-VI of the light source shown in FIG. 5, and FIG. 8 is a perspective view of a main part of the light source shown in FIG. 5.

The light source of the present embodiment is different from that of the first embodiment in that a spring member 101sp surrounds the side wall of the discharge tube 10 and a block 101bl thermally connected to the spring member 101sp comprises a heat radiating box. The difference is that it is attached to the side wall instead of the top of 101bx.

First, the spring member 101sp will be described. The spring member 101sp has a substantially cylindrical inner surface, which is in contact with the side wall of the cylindrical discharge vessel 1. A circumferential end of the spring member is not connected, and is bent so that a cross section perpendicular to the tube axis has an Ω shape, and a bolt inserted into two stupid holes BA provided in the spring member 101sp. Heat radiation block 101bl by B1 and B1
It is fixed to. In the no-load state, the diameter of the cylindrical inner surface of the spring member 101sp is slightly smaller than the diameter of the container 1, and this inner surface urges the peripheral region 1ws set on the container side wall, and The degree of adhesion of the peripheral region 1ws is improved.

The radiating block 101bl is provided with bolts B11, B12, B1 on the inner surface of the side wall of the radiating box 101bx.
3, B14.

Light exit window 1 located at the top of discharge tube 10
ww is exposed, and the light emitted therefrom is transmitted through the opening 101bxo of the heat dissipation box 101bx and the opening 1b1 of the outer box 100.
It is emitted to the outside via 00op.

Since the light source of this embodiment adopts this configuration, the above-described heat radiation block 101bl 'is omitted, but the configuration other than the above is the same as that of the first embodiment. According to the light source of the present embodiment, the spring member 101sp of the heat radiator surrounds the side wall 1w because the peripheral region 1ws is set on the surface of the side wall 1w of the discharge tube 19 so as to surround the tube axis of the discharge tube 10. In addition, since the heat radiator integrally surrounds the side wall 1w, the movement of the heat radiator 10 in the direction perpendicular to the tube axis can be restricted. (Third Embodiment) FIG. 9 is a longitudinal sectional view of a light source main body according to a third embodiment, FIG. 10 is a plan view of the light source main body shown in FIG. 9, and FIG. FIG. 12 is a perspective view of a main part of the light source shown in FIG.

First, the light source body will be described. The discharge tube 10 of the light source body has a circular area 1 wt.
The container 1 has a cylindrical side wall 1ws extending along the pipe axis from the outer periphery of the container 1. The bottom of the container 1 is sealed by a stem 15 having a flange. A gas such as deuterium is sealed in the container 1.

Filament 2c constituting cathode electrode
When power is supplied to the electrode 2, thermions emitted from the filament 2 c are emitted from the opening 3 a provided in the guide body 3, change the trajectory in the direction of the converging electrode 4, travel through the opening 4 a, and enter the anode electrode 2 a I do. Due to this discharge phenomenon, gas in the vicinity of the focusing electrode opening 4a emits light, and the light is emitted in the direction of arrow A through the light emission window 1ww located at the top of the discharge tube.

The focusing electrode 4 and the anode electrode 2a are insulated from each other via insulating members 7, 5, and the cathode electrode 2c,
A predetermined potential is applied to the anode electrode 2a and the focusing electrode 4 via lead pins 10a and 10b provided on the stem 15 side. The stem 15 is provided with a glass tube 13 communicating with the inside of the container, and the end of the glass tube 13 is closed. In addition, the glass tube 13 is used for the container 1 during manufacturing.
Used to introduce gas into the interior.

The stem 15 is a cylindrical glass block 1
5c, a cylindrical body 15a having a cylindrical surface in close contact with and fixed to the side wall cylindrical surface of the glass block 15c, and a flange 1 bent outward from the lower opening end surface of the cylindrical body 15a.
5b, and a seal member 15d interposed between the base portion and the inner surface of the container side wall 1ws. The base portion and the seal member 15d are made of metal such as SUS or Kovar, and the flange portion 15b is provided with a plurality of holes 21 parallel to the pipe axis.
b, the hole 21 also penetrates the seal member 15d.

The heat dissipation block 101bl is in contact with the circular region 1wt constituting the top of the container. In other words, the opening 101blo of the heat radiation block is provided with a through hole 101blt extending parallel to the tube axis, the opening end surface of which contacts the peripheral area 1ws of the light emitting window 1ww, and the light emitting window is opened through this opening. Light is emitted from the unit 1ww.

A fixing hole 21 'parallel to the tube axis is provided in the periphery of the heat radiation block 101bl. The hole 21' and the stem hole 21 are connected and fixed by bolts B1 and B2. . Specifically, the collar 1 of the stem 15
A screw groove is formed in 5d, and the heat radiation block 101bl is fixed to the stem 15 by screwing the threads of the bolts B1 and B2 into the screw groove. The longitudinal directions of the bolts B1 and B2 coincide with the tube axis. The diameter of the hole 21 ′ of the heat radiation block 101 bl is set in two stages, and the diameter farther from the stem 15 is larger than that near the stem 15. A helical spring member 101sp is disposed in the large diameter portion of the hole 21 ', and when the bolts B1 and B2 are tightened, the heat radiation block 101bl is pushed in the peripheral area 1ws direction by the restoring force of the spring member 101sp. The area 1ws is urged by the heat radiation block 101bl.
Therefore, the peripheral region 1ws and the heat radiation block 101bl
Has improved the degree of adhesion.

As shown in FIG. 11, when the light source main body is incorporated in the heat radiating box, the spring member 10b is placed between the wall located on the top of the heat radiating box 101bx and the heat radiating block 101bl.
1sp intervenes and the bolts B1 and B2
Is inserted from outside. The heat radiation block 101bl
And the inner surface of the heat radiating box 101bx are bolts B11, B12,
It is fixed by B13.

The light emitted from the light emitting window 1ww of the discharge tube 10 is supplied to the through hole 101blt of the heat radiating block, the through hole 101bxo of the heat radiating box, and the through hole 100o of the outer box 100.
The light is emitted outside through p. An air-cooling fan 102 is attached to the outer box 100 in the same manner as in the above-described embodiment, and the air introduced into the inside by the air-cooling fan 102 cools the inner box 101bx and then vents 101bl.
It flows outside through d. By cooling the inner box 101bx, the peripheral region 1 in contact with the heat radiation block 101bl
ws is cooled.

In this example, the substance can be efficiently prevented from adhering to the light exit window 1ww as in the above-described embodiment, but the discharge tube 10 is connected to the stem 15 constituting the bottom of the vessel 1. And the stem 15 and the radiators 101bx, 10
1bl and 101sp are fixed via a plurality of bolts (screw) B1 and B2 extending parallel to the tube axis. Since the stem 15 is used for fixing the radiator, an increase in the number of components required for fixing can be suppressed. (Fourth Embodiment) FIG. 13 is a longitudinal sectional view of a light source body according to a fourth embodiment, FIG. 14 is a plan view of the light source body shown in FIG. 13, and FIG. FIG. 16 is a perspective view of a main part of the light source shown in FIG.

The light source of the present embodiment is different from that of the third embodiment only in the shape of the heat radiation block 101bl, and the other configuration is the same. That is, the heat radiation block 1
01bl is a circular region 1w forming the top of the discharge tube 10.
Not only t but also the side surface 1ws.

More specifically, the heat radiating block 101bl that is in direct contact with the discharge tube 10 has a shape that covers the top of the container 1 of the discharge tube 10. The outer surface of the top of the container 1 is composed of a circular surface 1wt and a side surface of a cylindrical shape 1ws which is continuous with the outer periphery of the circular surface 1wt and extends about 20% or less of the tube length in a direction perpendicular to the circular surface. The heat radiation block 101bl is not in contact with a region having a predetermined radius from the center of the circular surface 1wt, and this region functions as the light exit window 1ww. That is, the center of the annular heat radiation block 101bl forms a through hole 101blt extending parallel to the tube axis, and the end of the through hole 101blt located inside the heat radiation block 101bl on the discharge tube side has the above-described shape. Circular surface 1w
Abuts on the peripheral region 1ws of t, the diameter of which expands from the contact position to the diameter of the container 1, and extends parallel to the tube axis.

As described above, the light source according to any of the above embodiments also includes a gas such as deuterium in the container 1 and discharges the electrode by a discharge between the pair of electrodes 2a and 2c disposed inside the container. A discharge tube 10 is provided for outputting light emitted from the gas between 2a and 2c to the outside through a light emission window 1ww located at the top of the container 1, and radiates heat to the surface of a peripheral region 1ws of the light emission window 1ww. The body is in contact. According to these light sources, light emission is output to the outside through the light emission window 1ww, but the peripheral area 1w of the light emission window 1ww.
The peripheral region 1ws is cooled by the heat dissipator in contact with the surface of s. Therefore, a large amount of substances generated by sputtering of the pair of electrodes 2c and 2a constituting the cathode or the anode adhere to the peripheral region 1ws, and the light exit window 1w.
The amount of substances attached to w decreases.

[0049]

According to the light source of the present invention, the life of the discharge tube can be extended.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a light source according to a first embodiment.

FIG. 2 is a sectional view of the light source shown in FIG. 1 taken along the line II-II.

FIG. 3 is a perspective view of a main part of the light source shown in FIG.

FIG. 4 is a graph showing a relationship between an operation time (hour) of a light source and a relative light output (measurement wavelength: 250 nm).

FIG. 5 is a longitudinal sectional view of a light source according to a second embodiment.

FIG. 6 is a sectional view taken along the line VI-VI of the light source shown in FIG.

FIG. 7 is a sectional view taken along the line VII-VII of the light source shown in FIG. 5;

8 is a perspective view of a main part of the light source shown in FIG.

FIG. 9 is a longitudinal sectional view of a light source body according to a third embodiment.

FIG. 10 is a plan view of the light source main body shown in FIG.

11 is a longitudinal sectional view of a light source obtained by incorporating the light source body shown in FIG. 9 into a heat dissipation box.

12 is a perspective view of a main part of the light source shown in FIG.

FIG. 13 is a longitudinal sectional view of a light source body according to a fourth embodiment.

FIG. 14 is a plan view of the light source body shown in FIG.

FIG. 15 is a longitudinal sectional view of a light source obtained by incorporating the light source body shown in FIG. 13 into a heat dissipation box.

FIG. 16 is a perspective view of a main part of the light source shown in FIG.

[Explanation of symbols]

10 ... discharge tube, 101bl ', 101sp, 101bl
... heat dissipating body, 101bx ... heat dissipating box, 1w ... side wall, 1ww ...
Light exit window, 1 ws...

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Nobuharu Harada, 1126 Nomachi, Ichinomachi, Hamamatsu City, Shizuoka Prefecture Inside of Tonics Co., Ltd. F-term in Tonics Corporation (reference) 5C015 JJ08 5C043 AA03 AA07 BB09 CC14 CD11 DD39 EA09

Claims (6)

[Claims] A gas is sealed in a container, and light emitted from the gas between the electrodes by discharge between a pair of electrodes disposed inside the container is provided with a light emission window located at the top of the container. A light source, comprising: a discharge tube that outputs the light to the outside via a light radiator; 2. The light source according to claim 1, wherein the heat radiator is in contact with the container such that the peripheral region is located at least on the top of the container. 3. The light source according to claim 2, wherein the heat radiator is in contact with the container such that the peripheral region is also located on a side wall of the container. 4. The discharge tube has a stem constituting the bottom of the vessel, and the stem and the radiator are fixed via a plurality of bolts extending parallel to the tube axis. The light source according to claim 2, wherein 5. The light source according to claim 1, wherein the peripheral region is set on a side wall surface of the discharge tube so as to surround a tube axis of the discharge tube. 6. One of the electrodes is a cathode made of a filament, the other of the electrodes is an anode for collecting thermoelectrons generated by energizing the filament, and the gas sealed in the container is heavy. The light source of claim 1, comprising hydrogen.