JP2017059483A - Ozone generation prevention unit for discharge lamp - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ozone generation prevention unit for discharge lamp.SOLUTION: An ozone generation prevention unit for discharge lamp includes a lamp for UV light emission, a lamp spacer, an ozone cut filter, a wave washer, and a filter presser placed, in order, from the emission port of the lamp in the direction of travel of the UV light, a free size gasket composed of an elastic material and placed in a split structure provided in the lamp spacer, first and second heat sinks adhering to the lamp, and an elastic fastener for fixing the lamp by fastening the split structure of the first and second heat sinks.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an ozone generation prevention unit for a discharge lamp, and more particularly to an ozone generation prevention unit for a discharge lamp that prevents the generation of ozone and eliminates the influence on the human body due to ozone exposure.

  Ozone derived from ultraviolet rays is generated by the reaction between ultraviolet rays having a light wavelength of 230 nm or less and oxygen in the air. The following are known as conventional techniques for preventing this.

(1) A method using an ozone-less lamp that does not propagate ultraviolet rays having a wavelength contributing to ozone generation into the air. A method of absorbing ultraviolet rays contributing to ozone generation using quartz glass doped with titanium as a bulb material. is there. However, as shown in FIG. 5 of Patent Document 1 (Japanese Patent No. 4736900), for example, even in the optimally finished curve A, light of 200 nm to 250 nm is blocked as a result of blocking light of 200 nm or less. It will be fading.
Further, light of 200 nm to 230 nm is propagated in the air, and ozone is also generated by light having a wavelength in this region. Therefore, according to the present technology, generation of ozone cannot be completely suppressed.

  The emission of the mercury lamp is a spectrum having a discontinuous wavelength (emission line emission), and the emission line with the highest intensity emits light at 184.95 nm and the next longer wavelength at 253.65 nm. The high-pressure mercury lamp emits light even between wavelengths of 184.95 nm and 253.65 nm, but the ratio of ozone generated by a wavelength of 200 nm or more is small because the emission intensity ratio is very small compared to the emission line emission. However, if the lamp output is increased, the ratio is harmful because at least ozone corresponding to the magnitude of the lamp output is generated. In the case of the Xe lamp, the emission spectrum becomes a continuous spectrum in the ultraviolet region, and there is no significant difference in the light intensity ratio between the wavelength desired to be transmitted and the wavelength desired to be blocked. This means that if a lamp with high radiation intensity is used in order to increase the intensity of the ultraviolet light that is desired to be used, the amount of ozone generated will be considerably increased.

(2) Method of exhausting generated ozone The atmosphere containing oxygen is replaced with an inert gas such as nitrogen gas, or a space through which ultraviolet rays pass is sealed.
Patent Document 2 (Japanese Patent Application Laid-Open No. 2012-247431) describes exhaust, replacement with an inert gas, and sealing of a space. By combining these methods, the generation of ozone is prevented and leakage to places other than the limited space is prevented. However, even in this method, some ozone is generated as described in the document. As the lamp output increases, the amount of ozone generated increases accordingly. Although prevention of ozone generation and leakage can be achieved by this method in a closed apparatus system, it is difficult to change the irradiation position, move the light source, and the like, which is not convenient.
For exhaust, preparation of exhaust device, replacement with inert gas, replacement pipes, preparation of active gas, sealing requires a sealed structure, etc. There will be disadvantages due to the increase in materials and the size of the equipment.

(3) A method of providing a filter for selecting a specific wavelength and emitting only light having a required wavelength to the atmosphere side In Patent Document 3 (Japanese Patent Laid-Open No. 7-29804), a light source part and an atmosphere part are isolated, and a light source An inert gas is supplied to the unit, and light of the selected wavelength is propagated through the window to the atmosphere side using a mirror that selects the wavelength.
In this method, wavelength selection is performed by a cold mirror (filter). However, since a cold mirror is used, the wavelengths that can be extracted are limited.

  The cold mirror has a sub-transmission band, and even if it has a fairly high performance, the reflection wavelength band is limited. In the propagation of light by reflection, the light having the wavelength that becomes the sub-transmission band cannot be reflected, and thus the wavelength range of the emitted light is limited. If it is a type that reflects the short wavelength side of the cold mirror and transmits the long wavelength side, it reflects the wavelength that generates ozone and propagates to the atmosphere side because the window material is quartz glass. In this case, ozone is generated. If the wavelength band that generates ozone is blocked, the mirror should be of the type that transmits the short wavelength side and reflects the long wavelength side. The light on the long wavelength side is lost due to the sub-transmission band of the cold mirror. If it is devised so that the long wavelength side is not lost, the short wavelength side is reflected, so that the wavelengths that can be emitted are limited.

  According to this method, it is difficult to prevent generation of ozone and emit a wide range of wavelengths from the ultraviolet region to a long wavelength. At the same time, since the cold mirror is used at an incident angle of 45 °, the slope of the transmittance curve becomes gentle between the blocking region and the transmitting region, and the separation performance between blocking and transmission is inferior. Furthermore, by using a mirror at 45 ° incidence, a large space is required for installation and it is not compact.

(4) A method of forming an ozone cut filter on the lamp bulb itself. Excelitas Technologies Corp. CermaxLamp manufactured by the company forms a film in a window corresponding to a lamp bulb, and transmits the film, thereby preventing a wavelength region in which ozone is generated. FIG. 1 is an illustration of Exceltechnology Technologies Corp. It is a figure which shows the spectral distribution of CermaxLamp (Xe lamp) made from the company, and the technical data "Cermax Xenon Lamp Engineering Guide-Excelitas (September 1, 2015 as of September 1, 2015: //downloads.com/Downloads). /Cermax_Eng_Guide.pdf) "
An excerpt from

The vertical axis is the amount of light, and the horizontal axis is the wavelength.
A line rising from around 300 nm shows a spectrum of a lamp in which a window is formed.
The line rising from around 200 nm shows the spectrum of the lamp not deposited on the window.
This method also blocks light in the 230 to 300 nm wavelength band, which is negligible for ozone generation, and cannot use this wavelength range. If the transmission band is extended to near 230 nm, it cannot be achieved unless the material of the membrane constituting the ozone cut filter is changed.

In order to obtain a transmission band up to 230 nm, it is necessary to use a multilayer film of HfO ₂ and SiO ₂ . In this case, since the heat resistance of HfO ₂ is inferior, it is necessary to enhance the cooling effect. However, since it is a component of the lamp, if the lamp itself is cooled too much, the performance and life of the lamp will be affected. In addition, when forming a film on a window, which is a component of a lamp, the window cannot be removed, so a test for confirming the performance as an ozone cut filter cannot be performed, and it cannot be replaced if necessary.

Japanese Patent No. 4736900 JP 2012-247431 A JP-A-7-29804

  The objective of this invention is providing the ozone generation prevention unit for discharge lamps which radiate | emits the ultraviolet-ray from 240 nm, without generating ozone.

Another object of the present invention is to provide an ozone generation prevention unit for a discharge lamp that emits light in a wide wavelength band of 240 nm or more without generating ozone.
It is another object of the present invention to provide an ozone generation prevention unit for a discharge lamp that can be removed and restored in order to confirm the performance of an ozone cut filter for preventing ozone exposure.
An object of the present invention is to further provide an ozone generation prevention unit for a discharge lamp of a type that does not use an inert gas or a discarding device in order to make it possible to change irradiation conditions and move and use a light source device and to improve convenience. It is to provide.
Another object of the present invention is to provide a compact ozone generation prevention unit for a discharge lamp in which an optical element is not damaged by heat from a lamp that generates heat and reaches several hundred degrees.

  An ozone generation prevention unit for a discharge lamp according to an embodiment of the present invention includes a lamp for emitting ultraviolet light, a lamp spacer arranged in order from the exit of the lamp in the ultraviolet traveling direction, an ozone cut filter, a wave washer, and a filter. A free-size gasket made of a resilient material disposed in a slit structure provided in the lamp spacer, a first heat radiating plate and a second heat radiating plate that are in close contact with the lamp, the first heat radiating plate, And a resiliently-fastening fastener that fixes the lamp and the lamp spacer by tightening a slit structure of the heat sink.

  The ozone cut filter is fixed to the second heat radiating plate with screws through the wave washer and the filter holder, and is easily removable.

  The filter holder is in direct contact with the second heat radiating plate.

  The ozone cut filter according to the embodiment of the present invention is characterized in that a long wave pass filter that transmits 240 nm or more and blocks 230 nm or less is formed on quartz glass.

  The ozone cut filter according to an embodiment of the present invention is formed by ion-assisted deposition.

According to the present invention, ozone harmful to the human body is not generated, and even when used in a closed room, a narrow dark room, etc., there is no problem of health damage due to ozone.
According to the present invention, when an impact is applied to the unit due to an accident or the like, the ozone cut filter can be removed, the performance can be inspected, and the unit can be replaced if necessary.
According to the present invention, it is not necessary to replace the exhaust device or the inert gas, so that a movable light source device can be provided.
According to the present invention, since it is not necessary to isolate a special inspection system for performance confirmation, the degree of freedom of the inspection system is increased and a multipurpose light source device can be provided.
According to the present invention, since the ozone generation prevention unit for a discharge lamp is compact, the light source device can also be manufactured compactly, and the device cost can be reduced.

Excelitas Technologies Corp. It is a figure which shows the spectral distribution of manufactured CermaxLamp (Xe lamp). It is an exploded view of the ozone generation prevention unit for discharge lamps by the embodiment of the present invention. It is sectional drawing of the ozone generation prevention unit for discharge lamps by embodiment of this invention. It is a figure which shows the spectral transmittance (design value) of the ozone cut filter by embodiment of this invention. It is the figure which expanded the slope part of the spectral transmittance of FIG.

  Embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  Since the spectrum of light emitted from the lamp includes light in a wavelength range that generates ozone, ozone is generated when light is emitted into a space where oxygen is present. By confining this space as narrow as possible, the generated ozone is confined in this space.

  The reason for making it as narrow as possible is not just to make it compact. Since ozone absorbs light in the vicinity of 250 nm, the longer the propagation distance in the space where ozone is, the more chances that ozone and light meet, the amount of light absorption increases, and the amount of light transmitted decreases. By narrowing the sealed space, the propagation distance can be shortened, the amount of light absorption can be relaxed, and more light near 250 nm can be propagated. Further, by sealing the space, it is possible to prevent ozone from leaking out and to prevent oxygen from going to and from the outside, thereby suppressing an increase in ozone.

FIG. 2 shows an exploded view of a discharge lamp ozone generation prevention unit according to an embodiment of the invention.
The frame material that forms a sealed space for confining ozone is the lamp spacer 5 and the ozone cut filter 8 that are provided in the UV traveling direction in the vicinity of the lamp outlet. Ozone is generated only in the space within the frame surrounded by these parts, and the light after passing through the ozone cut filter 8 does not include light of a wavelength that generates ozone.

  Sealing to confine the generated ozone uses a slit structure provided on the lamp spacer 5, a free size gasket 4 (weak elastic material), and a slit structure of the first radiator plate 2 and the second radiator plate 6. This is achieved by tightening the slits of the first heat radiating plate 2 and the second heat radiating plate 6 with the stoppers 1 and 7 having spring properties.

To seal between the ozone cut filter 8 and the lamp spacer 5, the wave washer 9 is sandwiched after the ozone cut filter 8, the filter holder 10 is screwed to the second heat radiating plate 6 with a specified torque, and the holding force by the wave washer 9 is Thus, the ozone cut filter 8 is brought into close contact with the lamp spacer 5.
Due to the moderate elasticity of the wave washer 9, a pressing force is applied to each part.

  It is necessary to use a slit structure, a free size gasket 4 and a wave washer 9 that follow the displacement of the volume so that the sealing performance does not deteriorate due to expansion and the ozone cut filter 8 is not damaged when each component is thermally expanded. There is.

  Each time the lamp is turned on and off, the parts related to sealing repeatedly expand and contract. The slit structure applied to the lamp spacer 5, the free size gasket 4, the first radiator plate 2, the second radiator plate 6, the stoppers 1, 7, the wave washer 9, and the filter retainer 10 are associated with expansion and contraction. Maintain a constant pressure on each other.

FIG. 3 shows a cross-sectional view of a discharge lamp ozone generation prevention unit according to an embodiment of the present invention.
The ozone cut filter 8 is a quartz glass formed with a long wave pass filter that transmits 240 nm or more and blocks 230 nm or less. If the long wave pass filter is used as a transmission type filter, the transmittance of the transmission band can be kept high except for the absorption factor of quartz glass as a substrate material and the atmosphere. That is, transmission of light in a wavelength band that generates ozone can be prevented, and a spectral distribution of a wider wavelength than that can be emitted to the atmosphere side.

FIG. 4 shows the spectral transmittance (design value) of the ozone cut filter 8 according to the embodiment of the present invention, and FIG. 5 shows an enlarged view of the slope portion of the spectral transmittance of FIG.
The steeper slope of the transmittance from the blocking region to the transmission region allows the transmission of light near 230 nm. In the ozone cut filter 8, the ozone generation wavelength of 230 nm or less is blocked, and at 240 nm, it can propagate into the atmosphere with the highest transmittance.

  Such a filter membrane having a steep slope of transmission generally has poor heat resistance, but can be stably used by properly cooling the ozone cut filter 8.

  As a function necessary for the ozone generation prevention unit for a discharge lamp, it is necessary to combine the role of cooling the lamp 3 itself and the role of protecting the ozone cut filter 8 from heat. The ozone cut filter 8 is arranged slightly apart from the lamp 3 by the lamp spacer 5 so that the lamp is not cooled too much and the heat generated by the lamp 3 is not transmitted to the ozone cut filter 8 as it is. Further, the ozone cut filter 8 is cooled by transmitting it to the second heat radiating plate 6 through the wave washer 9 and the filter holder 10.

  The lamp 3 and other parts are prevented from being damaged by heat, or the durability is improved. The first heat sink 2 in FIG. 2 cools the lamp, and the second heat sink 6 cools the lamp 3, the ozone cut filter 8, and other parts. The air is increased and cooled by flowing air through a small fan (not shown).

  The second heat radiating plate 6 is a component that serves as both a cooling component and a sealing component. This eliminates the need for exhaust equipment and a mechanism for flowing an inert gas, thereby reducing the size and cost of the unit.

The ozone generation prevention unit for a discharge lamp according to the embodiment of the present invention is independent of the structure of the lamp 3, and the ozone cut filter 8 can be removed, so that the performance confirmation is easy. The ozone cut filter 8 is improved in heat resistance when forming a film by ion-assisted vapor deposition, and is not damaged in a normal use state according to the embodiment of the present invention.
In addition, since the discharge lamp ozone generation prevention unit is compact, it has a structure in which safety can be easily confirmed.

実験結果から、オゾンカットフィルターを有する場合、オゾン生成が抑えられていることがわかる。 Table 1 shows the results of measurement of the amount of ozone generated when a 300 W ultraviolet Xe lamp was used in the ozone generation prevention unit for a discharge lamp according to the embodiment of the present invention under the condition of the presence or absence of an ozone cut filter.
In this experiment, a light source was installed in a clean room, and measurement was performed under a condition where the air flow rate by the cooling fan was 51 m ³ / min.

From the experimental results, it can be seen that ozone generation is suppressed when the ozone cut filter is provided.

DESCRIPTION OF SYMBOLS 1, 7 Stopper 2 1st heat sink 3 Lamp 4 Free size gasket 5 Lamp spacer 6 2nd heat sink 8 Ozone cut filter 9 Wave washer 10 Filter holder 11 Spring washer 12 Screw

Claims (5)

An ultraviolet light emitting lamp,
A lamp spacer, an ozone cut filter, a wave washer, and a filter holder, which are arranged in order from the exit of the lamp in the ultraviolet traveling direction;
A free-size gasket made of an elastic material arranged in a slit structure provided in the lamp spacer;
A first heat sink and a second heat sink closely contacting the lamp;
A stopper having elasticity to fix the lamp and the lamp spacer by tightening the slit structure of the first heat radiating plate and the second heat radiating plate;
An ozone generation prevention unit for a discharge lamp, comprising:   2. The ozone generation prevention for a discharge lamp according to claim 1, wherein the ozone cut filter is fixed to the second heat radiating plate with screws through the wave washer and the filter holder and can be easily removed. unit.   The ozone generation prevention unit for a discharge lamp according to claim 1, wherein the filter holder is in direct contact with the second heat radiating plate.   2. The ozone generation prevention unit for a discharge lamp according to claim 1, wherein the ozone cut filter is a quartz glass formed with a long wave pass filter that transmits 240 nm or more and blocks 230 nm or less.   The ozone generation prevention unit for a discharge lamp according to claim 4, wherein the ozone cut filter is formed by ion-assisted deposition.

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