JP2518067Y2 - Electrodeless discharge device - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrodeless discharge device for exciting an electrodeless lamp, in which a light emitting material such as mercury is enclosed, by microwaves to emit light.

[0002]

2. Description of the Related Art An electrodeless discharge device for exciting an electrodeless lamp filled with a light emitting material such as mercury with a microwave to emit light is often used as an ultraviolet ray source. It is applied to photolithography during device manufacturing and processing to improve the heat resistance of resist. In such an electrodeless discharge device, a rod-shaped electrodeless lamp is surrounded by a gutter-shaped mirror, and an antenna is provided in a gap between the mirror and the electrodeless lamp. here,
Since the electrodeless lamps are rod-shaped and long, the antennas are arranged one by one near the ends thereof. Then, the microwave generated by the magnetron is guided to the vicinity of both ends of the electrodeless lamp via the antenna. Therefore, due to the coupling of the microwaves introduced through the antenna, the light emitting material such as mercury sealed inside the bulb is excited and vaporized, and becomes a plasma state to emit light.

By the way, in the electrodeless lamp, a lamp holding portion is provided at both ends of the bulb so as to be attached to the discharge device. On the other hand, an exhaust pipe is required to fill an inert gas such as mercury or argon. Therefore, in the past, as shown in FIG.
As shown in, the lamp holding part 11 made of a solid glass rod is attached to one end of the bulb 10 made of quartz glass, and the exhaust pipe 13 is attached to the other end. Then, the inside of the valve 10 is exhausted from the exhaust pipe 13, and mercury, an inert gas, or the like is injected, and the exhaust pipe 13 is welded and sealed. Therefore, as shown in FIG.
14 is formed, and this seal portion 14 is used as the other lamp holding portion.

[0004]

In such an electrodeless lamp, since the antenna for guiding microwaves is arranged near the end of the electrodeless lamp, the end of the bulb becomes particularly hot. In other words, the seal part 14, which also functions as the lamp holding part, is exposed to high temperature, but the boundary surface between the seal part 14 and the inside of the bulb 10 is not a smooth surface, and a small gap 14a extends toward the inside of the seal part 14. Therefore, the gap 14a is exposed to high temperature. Therefore, the hole 15
There is a problem that valve 10 may become unusable in a short time before blackening.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an electrodeless discharge device in which a seal portion, which also functions as a lamp holding portion at the end of a bulb, does not have a hole and the lamp life is extended.

[0006]

To achieve the above object, the present invention provides a gutter-shaped mirror, a rod-shaped electrodeless lamp disposed so as to be surrounded by the mirror, a mirror and an electrodeless electrode. In an electrodeless discharge device consisting of an antenna that is interposed in the gap between the lamps and that guides microwaves to the electrodeless lamp, the lamp holders made of solid glass rods are directed outward at both ends of the bulb of the electrodeless lamp. In addition to projecting, the exhaust pipe remaining portion is provided on the side surface of the valve, and the antenna is provided at a position not facing the exhaust pipe remaining portion.

[0007]

In other words, the exhaust pipe remaining portion for enclosing mercury and the like is not used also as the lamp holding portion and is provided on the side surface of the bulb so as not to face the antenna, so that the exhaust pipe residual portion does not become too hot. There are no holes.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below with reference to the embodiments shown in the drawings. FIG. 1 is a schematic explanatory view of an electrodeless discharge device according to the present invention. In FIG. 1, a pair of microwave waveguides 5 is attached to the upper surface of a box-shaped microwave cavity wall 4 whose lower surface is opened, and a magnetron 6 serving as microwave generation means is arranged at the top of the waveguides 5. Has been done. A rod-shaped electrodeless lamp 1 is arranged in the cavity wall 4, and a gutter-shaped mirror 2 is arranged so as to surround the electrodeless lamp 1. The antennas 3 are arranged one by one between the both ends of the electrodeless lamp 1 and the mirror 2.
The end 3a of the is inserted into the waveguide 5. Therefore, the microwave generated by the magnetron 6 is transmitted to the antenna 3 through the waveguide 5 and guided from the antenna 3 to the vicinity of the end of the electrodeless lamp 1. A mesh 42 for microwave sealing is attached to the lower surface opening of the cavity wall 4.

The mirror 2 is a cold mirror in which a vapor-deposited film of a metal oxide is formed on the surface of glass over a dozen layers, and the transmittance of visible light having a wavelength of 450 nm or more and infrared light is 7
On the contrary, the reflectance of ultraviolet rays having a wavelength of 400 nm or less is 90% or more. Further, a plurality of ventilation holes 21 are formed at the top of the mirror 2. Vent holes 41 and vent holes 51 are also formed in the cavity wall 4 and the waveguide 5, respectively, and the cooling air from the blower blower 7 arranged above the vent holes 41 and 51 is as shown by arrows. The electrodeless lamp 1 and the mirror 2 are cooled by passing through.

Next, the bulb 10 of the electrodeless lamp 1 is made of a quartz glass tube having an outer diameter of 8 mmφ and a length of 290 mm.
At both ends of the bulb 10, a lamp holding portion 11 made of a solid glass rod is provided so as to project outward. The electrode holder 1 is attached to the cavity wall 4 by holding the lamp holder 11 with a holder (not shown). Also the valve
An exhaust pipe remainder 12 is provided on the side surface of the central part of 10. That is, the inside of the valve 10 is exhausted by the exhaust pipe attached to the side surface of the center of the valve 10, and mercury or an inert gas is injected.After that, the exhaust pipe is welded to tip off the exhaust pipe. The remaining part 12 is formed. Therefore, a clearance similar to the clearance 14a shown in FIG. 3 is formed inside the exhaust pipe residual portion 12. Further, since the position of the remaining portion 12 of the exhaust pipe is the central portion of the valve 10, it does not face the antenna 3.

When the object to be treated is placed below the electrodeless discharge device and the magnetron 6 is activated, microwaves are guided to the vicinity of the end of the electrodeless lamp 1 by the antenna 3. As a result, the light-emitting material such as mercury sealed inside the bulb 10 is excited, becomes a plasma state, emits light, and irradiates the object to be treated with ultraviolet rays. At this time, the temperature in the vicinity of the end of the valve 10 is high because it faces the antenna 3, but the exhaust pipe remaining portion 12 in the center of the valve 10 is not so high because it does not face the antenna 3. By the way, when the temperature of the valve 10 was measured, it was about 750 ° C near the end, but about 720 ° C at the center.
Met. For this reason, even though a gap similar to the gap 14a shown in FIG. 3 is formed inside the exhaust pipe residual portion 12, the hole is hardly opened. Therefore, the electrodeless lamp 1 can be used until the bulb 10 is blackened and the amount of ultraviolet radiation is reduced to about 70% of the initial value, and it is not disabled in a short time.

[0012]

As described above, in the electrodeless discharge device of the present invention, the lamp holding parts made of solid glass rods are provided outwardly at both ends of the bulb of the electrodeless lamp, and Since the exhaust pipe remaining portion is provided on the side surface and the antenna for guiding the microwave is provided at a position not facing the exhaust pipe remaining portion, the temperature rise of the exhaust pipe remaining portion is suppressed. Therefore, there is no hole in the remaining portion of the exhaust pipe, and the lamp life is extended.

[Brief description of drawings]

FIG. 1 is a schematic explanatory view of an embodiment of the present invention.

FIG. 2 is an explanatory view of a method for manufacturing a conventional bulb of an electrodeless lamp.

FIG. 3 is an explanatory diagram of a bulb of a conventional electrodeless lamp.

[Explanation of symbols]

 1 Electrodeless Lamp 10 Bulb 11 Lamp Holding Part 12 Exhaust Pipe Remaining 13 Exhaust Pipe 14 Sealing Part 15 Hole 2 Mirror 3 Antenna 4 Microwave Cavity Wall 5 Microwave Waveguide 6 Magnetron 7 Blower Blower

Claims (1)

(57) [Scope of utility model registration request] 1. A trough-shaped mirror, a rod-shaped electrodeless lamp arranged so as to be surrounded by the mirror, and a microwave which is interposed in a gap between the mirror and the electrodeless lamp to guide a microwave to the electrodeless lamp. In the electrodeless discharge device including an antenna, the electrodeless lamp has a lamp holding portion made of a solid glass rod protruding outward at both ends of the bulb, and an exhaust pipe remaining portion on a side surface of the bulb. An electrodeless discharge device, wherein the antenna is provided at a position that does not face the remaining portion of the exhaust pipe.