TWI486997B - Metal halide lamp and metal halogen lamp lighting device - Google Patents

Description

Metal halide lamp and metal halide lamp lighting device

The present invention relates to a metal halide lamp and a metal halide lamp lighting device.

In the manufacturing process of the liquid crystal display panel, when a glass substrate is bonded, a long-arc metal halide lamp is suitably used as an ultraviolet light source for hardening a sealant applied between a glass substrate and a glass substrate. In this manufacturing process, a lighting device including a rod-shaped metal halide lamp and a mirror disposed on the back surface thereof is used.

The device is shown in Figure 4. The metal halide lamp 61 is disposed in the lamp housing 60. A mirror 62 is disposed above the metal halide lamp 61, and the radiation from the lamp is irradiated onto the workpiece W disposed below. The workpiece W is coated with a sealant 65 between the glass substrate 63 and the glass substrate 64 as described above.

In such an application, ultraviolet irradiation of a region having a wavelength of 300 to 400 nm is required depending on the characteristics of the sealing agent 65. Therefore, it is suitably used for the metal halide lamp 61 in which iron is sealed inside the arc tube, and good light radiation can be obtained by the iron in the wavelength band.

Recently, in the manufacturing process of the liquid crystal display panel described above, in order to reduce the amount of electric power required for manufacturing, the input electric power of the metal halide lamp is switched between the irradiation of the workpiece and the non-irradiation to reduce the non-irradiation. The way of electricity is carried out. For example, in order to process one workpiece, the lamp is turned on for a relatively high power for several tens of seconds, and then the workpiece after the irradiation is removed, until the next workpiece is transported, for several tens of seconds. It is a light that is blocked by the illumination of the light and switched to a relatively low power.

An example of such a lighting method is described. In the initial stage of lighting, the "higher power" described above is the same as "lower power", but the lamp is deteriorated as the lamp is used. When the amount of light emitted by the workpiece is reduced, it is only necessary to increase the power value during the period of "higher power". For example, when the amount of light radiation at the initial stage of the lamp is reduced by 5%, the power value is adjusted (rised) by returning the relatively high power to the initial amount of light radiation to compensate for the lamp. The illuminance produced by the accumulated lighting time is reduced. In this way, the current, voltage, and power of the lamp change with time as the lamp is used.

Further, the relatively high electric power is, for example, electric power that is 50% or more higher than the rated power consumption, and the relatively low electric power is electric power that is set to be lower than the relatively high electric power. Moreover, for convenience, the mode of lighting with relatively high power is referred to as "constant power lighting mode"; the current is supplied with lower power than the constant power lighting mode, that is, it will be relatively low. The mode in which the power is turned on is called "saving power lighting mode".

In this way, the constant power lighting mode and the power saving lighting mode are used to alternately switch between higher power and lower power, that is, using a so-called quasi-like intermittent lighting to drive the metal halide lamp in a power-saving manner. At the same time, switching of the lamp can be performed quickly compared to turning ON/OFF the lamp, and it is possible to continuously process a large number of workpieces.

Fig. 5 is an explanatory view showing a metal halide lamp 50 of the prior art, and is a cross-sectional view taken along the plane passing through the tube axis. As shown in the figure, the metal halide lamp 50 is provided with a sealing portion 55a at both ends of the arc tube 51, and a molybdenum foil 54 is embedded in the sealing portion 55a.

The electrode 52 is made of tantalum tungsten containing ruthenium oxide in tungsten, and the shaft portion of the electrode 52 extends toward the sealing portion and is connected to the molybdenum foil 54 described above. A cylindrical holding member 56 made of quartz glass is disposed around the electrode shaft portion 53. The outer peripheral surface of the holding member 56 is fused and joined to the inner peripheral surface of the arc tube 51.

Here, the metal halide lamp is represented by a specific numerical example, and the outer diameter of the arc tube 51 is 26.1 mm, the inner diameter is 22.5 mm (wall thickness: 1.8 mm), and the total length of the sealing portion is 600 mm, and the distance between the electrodes (light emission) The length) is 500mm.

The outer diameter of the large diameter portion of the tip end portion of the electrode 52 was 3.5 mm, and the outer diameter of the shaft portion 53 composed of the thin outer diameter was 2.5 mm.

Further, the inner diameter of the holding member 56 made of quartz glass was 2.6 mm, and the total length thereof was 2 mm.

In the molybdenum foil 54 , two sheets are disposed in one of the sealing portions, and the entire length is 31 mm, and a rod-shaped sealing member made of quartz glass is interposed and contracted and sealed.

Further, the enclosure enclosed in the arc tube 51 is a rare gas, a predetermined amount of halogen, and at least iron. The input power of the lamp is 7kW to 14kW, and the input current is 7A to 28A.

[Previous Technical Literature]

[Patent Document 1] Japanese Laid-Open Patent Publication No. 2006-134710

However, when the metal halide lamp is operated in such a manner that the higher input and the lower input are alternately switched intermittently as described above, the metal halide enclosed as the luminescent substance may be biased in the halogen lamp lighting. Since the sealing portion of the relatively low temperature portion is moved, effective light emission of the sealed material (metal) cannot be obtained, and the illuminance may be lowered.

Further, the metal halide segregated in the sealing portion may be corroded by the molybdenum foil embedded in the sealing portion to cause corrosion, and the conduction may not be maintained. Further, in order to suppress such a reaction with the molybdenum foil, it is also possible to design a structure to prevent the entry of metal halides in comparison with the conventional structure in which the temperature of the sealing portion is further increased. However, in practice, if the temperature is raised to such an extent that the penetration of the sealant can be suppressed, the sealing of the foil due to exposure of the molybdenum foil to high temperatures causes a problem due to other factors, so that even if the sealing portion is raised The temperature of the halogen lamp cannot be extended.

Here, in order not to cause segregation of the metal halide to the sealing portion of the long arc type metal halide lamp, the foil is corroded or the foil is blown due to the high temperature, and the like, and the object of the present invention is therefore It is to provide a metal halide lamp in which the metal halide does not infiltrate into the sealing portion by lowering the temperature of the sealing portion while the metal is sealed, and further, providing a power supply device The constant power lighting mode and the power saving lighting mode, and the unique lighting method by switching the current to turn on the light, even when the halogen lamp is lit, the metal halogen lamp can be prevented from having the above-mentioned problem, and the halogen can be grown. A metal halide lamp lighting device for the life of the lamp.

(1) The metal halide lamp of the present invention contains iron as a luminescent material in an arc tube made of quartz glass, and a holding cylinder for supporting a shaft portion of the electrode at both ends of the arc tube, and A metal halide lamp in which a molybdenum foil is embedded in a sealing portion, wherein the length of the holding cylinder is L (mm), and when the current of the lamp is I (A), L/I (L/I) The mm/A) is 0.17 or more, and at least one of tin, antimony, gallium, lead, and zinc is enclosed in the inside of the above-mentioned arc tube.

(2) The metal halide lamp lighting device of the present invention is a metal halide lamp lighting device comprising: a power supply device for supplying electric power to the metal halide lamp, wherein the power supply device is provided : Constant power lighting mode and power saving lighting mode that supplies current with less power than the constant power lighting mode.

(1) It is possible to prevent the metal from entering the sealing portion, and it is possible to prevent corrosion and melting of the foil, so that metal light can be maintained for a long period of time, and a long-life metal halide lamp can be produced.

(2) For the metal halide lamp lighting device, the power saving mode can be performed by switching between the steady power lighting mode and the power saving lighting mode in which the current is supplied at a lower power than the constant power lighting mode. The lighting is turned on, and the metal halide lamp can be made to perform such power switching, and the illuminance is less likely to be reduced due to the loss of the luminescent material.

Hereinafter, embodiments of the present invention will be described based on the embodiments.

Fig. 1 is a cross-sectional view showing the basic configuration of a long arc type metal halide lamp of the present invention, which is cut in the tube axis direction. The metal halide lamp 10 is provided with a sealing portion 11a at both ends of the arc tube 11, and electrically connects the molybdenum foil 14 and the electrode 12 in the sealing portion 11a. The arc tube 11 is made of quartz glass which is excellent in permeability to ultraviolet light.

In the second drawing, the electrode 12 is made of tantalum tungsten containing ruthenium oxide in tungsten, and the shaft portion of the electrode 12 extends toward the sealing portion, and is connected to the molybdenum foil 54 described above and then to the outer guiding rod 15. A cylindrical holding member 16 made of quartz glass is disposed around the electrode shaft portion 13. The outer peripheral surface of the holding member 16 is fused and joined to the inner peripheral surface of the arc tube 11, so that the electrode shaft portion 13 is held. status.

In the metal halide lamp 10, at least the luminescent material is contained in the interior S of the arc tube 11, and at least the luminescent material contains iron. In such a metal halide lamp 10, iron is an essential luminescent material that is enclosed by ultraviolet rays having a wavelength of 300 nm to 400 nm which is mainly emitted. In addition, mercury can be sealed at the same time as iron.

Fig. 2 is an enlarged view showing the sealing portion 11a. In the present invention, when the length of the quartz glass holding member 16 disposed around the electrode shaft portion 13 is L (mm) and the current I of the halogen lamp is (A), the L/I (mm/A) is obtained. The relationship is set to 0.17 or more. This is because the current density is high when the current value of the lamp is large, so the heat in the vicinity of the sealing portion 11a also becomes high, so that the influence of heat is relative to the molybdenum foil 14 embedded in the sealing portion 11a. Since it is larger, the length of the holding member 16 is lengthened in accordance with the magnitude of the current, and the position of the molybdenum foil 14 is made distant from the discharge space S. As a result, it is possible to prevent the molybdenum foil 14 from being heated and dissolved, and it is possible to stably maintain the current supply state.

Further, as described above, the current of the lamp is gradually increased depending on the attenuation of the amount of light irradiated by the lamp, so that the highest arrival current changes as the cumulative lighting time of the lamp passes ( It goes higher, but the input current of the lamp does not always exceed the rated current consumption of the lamp in a higher way. Therefore, in the above relationship of L/I (mm/A), for I(A), the length L (mm) of the holding member 16 is set in advance by using the value of the rated consumption current, no matter what point The state of the lamp to drive the lamp can prevent overheating of the sealing portion and can be stably driven.

On the other hand, if the length of the holding member 16 is made longer than the conventional one in such a manner as to satisfy the above relationship L/I ≧ 0.17, since the discharge space S and the molybdenum foil are increased as the holding member 16 is lengthened The amount of metal halide that permeates into the end portion K of the molybdenum foil 14 increases as the temperature difference of the end portion K of 14 increases. In such a case, the amount of luminescence of the metal in the discharge space S is reduced to cause a decrease in illuminance.

Here, in order to avoid the loss of such a metal halide, in the invention of the present invention, a specific metal having a vapor pressure higher than that of iron is encapsulated, although it cannot directly contribute to light emission. Specifically, it is one of a metal such as tin, antimony, gallium, lead or zinc. These specific metals can be easily enclosed in a state of a suitable halogen compound.

Since the specific metal group is a substance having a vapor pressure higher than that of iron, a complex compound is produced by the metal and iron (Fe), and the vapor pressure can be increased in the halogen lamp lighting. As a result, the iron that has previously infiltrated into the sealing portion does not enter the vicinity K of the molybdenum foil 14 of the sealing portion 11a, and can remain in the discharge space S.

Here, an example of the ratio of the above-mentioned metal to iron is given. The ratio of atomic ratio to tin (Sn) to iron (Fe) is 0.25, and the ratio of bismuth (Bi) to iron (Fe) is Bi/Fe. Is 0.14. Of course, for other metals, it is preferable that the atomic ratio with iron is encapsulated in a suitable range.

According to the invention of the present invention, the metal-halogen lamp is lit by the constant power lighting mode and the power-saving lighting mode which is lower than the constant power lighting mode, and the heat distribution state of the arc tube is generated. Significantly uneven, or the luminescent material infiltrates into the interior of the sealing portion to lower the illuminance, or the molybdenum foil embedded in the sealing portion reacts with the metal halide to corrode and impair the conduction state of the power supply portion, or the molybdenum foil All problems such as overheating and dissolution can be eliminated, so that a metal halide lamp that maintains long-term stable illumination can be provided.

Hereinafter, the examples of the present invention will be described, but the present invention is not limited to the configuration described later.

Various lamps basically including the metal halide lamp shown in Fig. 3 were produced.

The material of the arc tube is quartz glass, and the outer diameter of the tube is 26.1 mm, and the inner diameter is 22.5 mm (wall thickness: 1.8 mm).

As the luminescent material, iron was sealed at a ratio of 0.011 mg/cc, and mercury was sealed at a ratio of 0.17 mg/cc. Iron and tin are enclosed in the same ratio as above. Further, as a metal having a higher vapor pressure than iron, the atomic ratio of tin (Sn) to iron is sealed at a ratio of Sn/Fe = 0.25.

The metal halide lamps of Examples 1 to 7 were produced, in which the length of the arc tube and the length of the distance between the electrodes were changed so that the current was 7 (A) to 28 (A), and the holding members were disposed at both ends of the arc tube. The length L is 4.8 (mm) to 13.2 (mm), and the size of L/I is in the range of 0.17 to 1.89.

Further, a metal halide lamp as a comparative example was produced in which any specific metal having a vapor pressure higher than that of iron was not enclosed in the arc tube, and the length L of the holding member was 0.07 to 0.13 with respect to the lamp current. Further, the current I was 15 A to 27 A, the distance between the electrodes was 1100 mm, and the length of the holding member was 2 mm.

Each of the metal halide lamps of the above-described Embodiments 1 to 7 and Comparative Example 1 was divided into two stages of rated power consumption and electric power of about 50% or less with respect to the rated power consumption, and the lighting was switched every 30 seconds. As a result, in the metal halide lamp of Comparative Example 1, after the 542 hours of lighting, the molybdenum foil was overheated and was not turned on. In the metal halide lamps of the other Examples 1 to 7, the state of the molybdenum foil did not change after 1000 hours of lighting, and no metal halide agglomeration was observed.

According to the invention as described above, in order to maintain the temperature of the molybdenum foil embedded in the sealing portion at a low level, the holding member for growing the shaft portion of the electrode can be used, and the current increase with respect to the lamp can be 0.17 mm/A or more. Increasing the distance between the discharge space and the molybdenum foil can avoid the problem of the foil causing the dissolution, and by lowering the vicinity of the molybdenum foil, the metal halide in the discharge space becomes more likely to penetrate, but as the main The iron of the luminescent substance is formed by a specific metal which is sealed with a higher vapor pressure, and the specific metal to be encapsulated and iron (Fe) form a composite compound to increase the vapor pressure. As a result, the metal halide can be stably retained in the metal halide. Discharge space.

By implementing such a configuration, it is possible to make a strong metal halide lamp for intermittently lighting operations of high input and low input, and on the other hand, when used for a long time, as a further The problem is that the electrode is stretched under intermittent lighting, which causes a problem that the molybdenum foil and the electrode are joined off. With such a problem, by increasing the number of molybdenum foils embedded in the sealing portion to two or more, the strength of the welded portion can be increased, and a longer-life metal halide lamp can be produced.

Further, the present invention is of course not limited to the contents of the above-described embodiments and examples, and can be appropriately changed. For example, in the above embodiment, mercury is sealed as a luminescent material simultaneously with iron, but it may be implemented only by iron. When mercury is not enclosed, the same current value as when mercury is enclosed can be obtained by increasing the amount of the rare gas enclosed or reducing the diameter of the arc tube.

10. . . Metal halide lamp

11. . . Luminous tube

11a. . . Sealing part

12. . . electrode

13. . . Electrode shaft

14. . . Molybdenum foil

15. . . External guide rod

16. . . Electrode shaft holding member

S. . . Discharge space

K. . . Molybdenum foil electrode side end

Fig. 1 is a cross-sectional view showing the direction of the tube axis of the metal halide lamp in the present case.

Fig. 2 is an enlarged view showing the main part.

Fig. 3 is a graph summarizing the L/I of the lamp in the embodiment and the lamp in the comparative example.

Fig. 4 is a view for explaining a light irradiation device in the manufacture of a liquid crystal panel.

Fig. 5 is a view showing the constitution of a prior art metal halide lamp.

10. . . Metal halide lamp

11. . . Luminous tube

11a. . . Sealing part

12. . . electrode

13. . . Electrode shaft

14. . . Molybdenum foil

15. . . External guide rod

16. . . Electrode shaft holding member

S. . . Discharge space

Claims (2)

A long-arc metal halide lamp comprising iron as a luminescent material in an arc tube made of quartz glass, and a holding cylinder for supporting a shaft portion of the electrode at both ends of the arc tube, and sealing A long arc type metal halide lamp in which a molybdenum foil is embedded in a stopper, wherein the length of the holding cylinder is L (mm), and when the current of the lamp is I (A), L/I (mm/A) is 0.17 or more, and a specific metal is sealed inside the arc tube, and the specific metal is at least one of tin, antimony, gallium, lead, and zinc. A metal halide lamp lighting device characterized by comprising: a long arc type metal halide lamp as described in claim 1; and a power supply device for alternately switching the following modes to supply power to the long arc type metal halide lamp: The constant power lighting mode is powered by a condition that is 50% or more higher than the rated power consumption of the metal halide lamp, and saves the power lighting mode, and supplies current using power lower than the above-described steady power lighting mode.