JP2009123487A - High frequency discharge lamp system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high frequency discharge lamp system that reduces the electricity transmission loss and simplifies the structure. <P>SOLUTION: The high frequency discharge lamp system includes: an electromagnetic wave transmission portion 14 transmitting the electromagnetic wave generated by a power supply 12; an electromagnetic wave radiation portion 18 introducing the electromagnetic wave transmitted from the electromagnetic wave transmission portion 14 to radiate it; and a discharge tube 22 discharging to emit light with plasma generated on receiving the electromagnetic wave introduced by the electromagnetic wave radiation portion 18. The electromagnetic wave radiation portion 18 has an inner conductor 19 transmitting electromagnetic wave from the electromagnetic wave transmission portion 14, an outer conductor 20 covering the inner conductor 19, and a spacer 21 laid between the internal conductor 19 and the outer conductor 20. When the outer diameter of the inner conductor 19 is d; the inner diameter of the outer conductor 20 is D; and the dielectric constant of the spacer 21 is ε, then D/d satisfies the relationship 1.5≤D/d≤40, and ε satisfies the relationship 1≤ε≤10. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a high-frequency discharge lamp system provided with an antenna for concentrating electromagnetic waves in a discharge tube.

  As an example of a high frequency discharge lamp, an electrodeless discharge lamp having no electrode in a discharge space is known. Since this type of electrodeless discharge lamp has no filaments or electrodes in the discharge space, the life of the electrodeless discharge lamp does not decrease due to the exhaustion of the filaments or electrodes, and the life can be extended compared to fluorescent lamps and incandescent bulbs. In addition, since the electrodeless discharge lamp has no electrode, there is no restriction on the substance that can be used as an electrode, and a substance with good light emitting performance can be arranged in the discharge space, which is more than that of a discharge lamp using an electrode. Efficiency can be increased.

  Conventionally, when configuring a high-frequency discharge lamp, it comprises a power source for generating electromagnetic waves, an arc tube that emits light without electrode by discharge light emission, and an electromagnetic wave irradiation unit that includes excitons for introducing electromagnetic waves into the arc tube, In a configuration in which a power supply unit and an electromagnetic wave irradiation unit are connected using a coaxial tube or a coaxial cable, reflected wave detection means for detecting a reflected wave propagating from the arc tube to the power supply unit side, and measurement information from the reflected wave detection means Based on the above, there has been proposed a high-frequency discharge lamp device provided with output adjusting means for adjusting the output of the power supply unit so as to minimize the reflection loss (see Patent Document 1).

  According to this high-frequency discharge lamp device, the reflected wave propagating from the arc tube to the power supply side is detected by the reflected wave detection means, and the output of the power supply unit is set to minimize the reflection loss based on the detected reflected wave. By adjusting with the output adjusting means, power can be efficiently supplied to the arc tube.

JP 2006-147454 A (refer to pages 4 to 5 and FIG. 1)

  In the prior art, in order to efficiently supply power to the arc tube, the reflected wave propagating from the arc tube to the power supply side is detected by the reflected wave detecting means, and the reflection loss is based on the detected reflected wave. The output of the power supply unit must be adjusted by the output adjustment means to minimize the power consumption, and the configuration is complicated and the cost is increased because the reflected wave detection means and the output adjustment means are required.

  The present invention has been made in view of the above-described problems of the prior art, and an object thereof is to provide a high-frequency discharge lamp system capable of suppressing power transmission loss and simplifying the configuration.

  In order to achieve the above object, a high-frequency discharge lamp system according to claim 1 includes a power supply unit that generates electromagnetic waves, an electromagnetic wave transmission unit that transmits electromagnetic waves generated from the power supply unit, and an electromagnetic wave transmitted from the electromagnetic wave transmission unit. In a high frequency discharge lamp system comprising an electromagnetic wave irradiation unit that irradiates and radiates, and a discharge tube that discharges and emits light by plasma generated by receiving the electromagnetic wave introduced by the electromagnetic wave irradiation unit, the electromagnetic wave irradiation unit includes: An inner conductor for introducing electromagnetic waves, a cylindrical outer conductor covering the inner conductor, and a heat insulating member interposed between the inner conductor and the outer conductor, wherein the outer diameter of the inner conductor is d, When the inner diameter of the outer conductor is D and the dielectric constant of the heat insulating member is ε, D / d satisfies the relationship 1.5 ≦ D / d ≦ 40, and ε has the relationship 1 ≦ ε ≦ 10. A composition that satisfies It was.

  (Function) The ratio D / d between the inner diameter D of the outer conductor and the outer diameter d of the inner conductor in the electromagnetic wave irradiation portion is 1.5 ≦ D / d ≦ 40 according to the value of ε (1 ≦ ε ≦ 10). Optimized within the range and impedance matching between the electromagnetic wave transmission part and the electromagnetic wave irradiation part, so the reflected wave detection means to detect the reflected wave propagating from the discharge tube to the power supply part side, the detection of the reflected wave detection means Without providing an output adjusting means for adjusting the output of the power supply unit to minimize the reflection loss based on the reflected wave caused by the electromagnetic wave, it is possible to suppress a decrease in efficiency associated with the transmission of electromagnetic waves and simplify the configuration. be able to.

  In the high-frequency discharge lamp system according to claim 2, in the high-frequency discharge lamp system according to claim 1, the heat insulating member is made of a discharge preventing material.

  (Operation) By using any one of discharge preventing materials such as quartz glass, alumina, and Teflon (registered trademark) for the heat insulating member, it is possible to prevent discharge from occurring between the inner conductor and the outer conductor, Non-lighting of the discharge tube due to discharge between the inner conductor and the outer conductor can be prevented.

  In the high-frequency discharge lamp system according to claim 3, in the high-frequency discharge lamp system according to claim 1 or 2, when the heat insulating member is air, the D / d is 1.5 ≦ D / d ≦ 2. 0, when the heat insulating member is foamed Teflon (registered trademark), the D / d is 2.0 ≦ D / d ≦ 5.0, and when the heat insulating member is quartz glass, the D / d is When 5.0 ≦ D / d ≦ 10.0 and the heat insulating member is alumina, the D / d is configured to satisfy 10.0 ≦ D / d ≦ 40.0.

  (Operation) By adjusting D / d according to the dielectric constant ε of the heat insulating member, the electromagnetic wave transmission unit and the electromagnetic wave irradiation unit can be impedance-matched even if the output impedance of the power source is 50Ω or 75Ω.

  As is apparent from the above description, the high frequency discharge lamp system according to claim 1 can suppress a decrease in efficiency associated with the transmission of electromagnetic waves and can simplify the configuration.

  According to the second aspect, it is possible to prevent unlighting of the discharge tube due to discharge between the inner conductor and the outer conductor.

  According to the third aspect, even when the output impedance of the power source is 50Ω or 75Ω, the electromagnetic wave transmission unit and the electromagnetic wave irradiation unit can be impedance-matched.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a configuration diagram including a cross section of a main part of a high-frequency discharge lamp system showing a first embodiment of the present invention, and FIG. 2 is a parameter when power transmission loss of an electromagnetic wave irradiation unit is measured with an output impedance of a power source set to 50Ω. FIG. 3 is a diagram for explaining the relationship between the parameter and the reflection loss when the power transmission loss of the electromagnetic wave irradiation unit is measured by setting the output impedance of the power source to 75Ω. FIG. 4 is a block diagram including a main section of a high-frequency discharge lamp system according to a second embodiment of the present invention, and FIG. 5 is a configuration including a main section of the high-frequency discharge lamp system according to a third embodiment of the present invention. FIG. 6 is a block diagram including a main section of a high-frequency discharge lamp system showing a fourth embodiment of the present invention, and FIG. 7 is a main section of the high-frequency discharge lamp system showing a fifth embodiment of the present invention. Including the configuration diagram, FIG. It is a block diagram including the principal part cross section of the high frequency discharge lamp system which shows 6th Example.

  In FIG. 1, a high frequency discharge lamp system 10 introduces and irradiates a power supply unit 12 that generates electromagnetic waves, an electromagnetic wave transmission unit 14 that transmits electromagnetic waves generated from the power supply unit 12, and an electromagnetic wave transmitted from the electromagnetic wave transmission unit 14. An electromagnetic wave irradiation unit 18 and a discharge tube 22 that discharges and emits light using plasma generated by receiving the electromagnetic wave introduced by the electromagnetic wave irradiation unit 18 are provided.

  The power supply unit 12 includes an oscillation unit 13 that generates an electromagnetic wave in a microwave band (1 to 100 GHz) by electric power supplied from an in-vehicle battery. The oscillation unit 13 is, for example, a magnetron or a semiconductor switching element (FET or bipolar transistor). Etc.).

  The electromagnetic wave transmission unit 14 is formed of a metal circular pipe-shaped inner conductor 15, a metal circular pipe-shaped outer conductor 16 surrounding the inner conductor 15, and a circular pipe, and the inner conductor 15, the outer conductor 16, A dielectric member 17 made of quartz glass, which is an insulating member, is coaxially integrated. The inner conductor 15 and an outer conductor surrounding the inner conductor 15 are configured as, for example, a coaxial tube or a coaxial cable. Electromagnetic waves are transmitted between 16.

  The electromagnetic wave irradiation unit 18 is formed of a metal circular pipe-shaped inner conductor 19, a substantially hollow cylindrical shape, and a metal outer conductor 20 surrounding the inner conductor 19, and a circular pipe-shaped inner conductor 19. A heat insulating member interposed between the outer conductor 20, for example, a quartz glass spacer 21 is coaxially integrated, and serves as a launcher for introducing electromagnetic waves into the discharge tube 22. The longitudinal end is connected to the longitudinal end of the discharge tube 22.

  An annular flange 19 a is formed on one end in the longitudinal direction of the internal conductor 19, and this flange 19 a is press-fitted on the inner peripheral side of the internal conductor 15 of the electromagnetic wave transmission unit 14. That is, the inner conductor 15 and the inner conductor 19 are electrically connected via the flange 19a. Further, an annular step portion 20a is formed on one end side of the outer conductor 20 in the longitudinal direction, and an annular flange 20b is formed on the other end side in the longitudinal direction. One end side in the longitudinal direction of the outer conductor 16 is press-fitted. That is, the outer conductor 16 and the outer conductor 20 are electrically connected through the step portion 20a. Further, one end in the longitudinal direction of the spacer 21 is coupled to one end in the longitudinal direction of the dielectric 17 of the electromagnetic wave transmission unit 14, and the other end in the longitudinal direction of the spacer 21 is supported by the flange 20 b of the external conductor 20.

The discharge tube 22 pinch-seals both ends of a glass (anhydrous quartz glass) tube in which an elliptical spherical bulge 23 is formed in the middle of the longitudinal direction, so that conductor assemblies 26 and 27 are attached to the pinch seals 24 and 25. It is sealed and has a double end type in which the inside of the oval bulge 23 is a discharge space 28. Then, in the spheroidal bulged portion 23 of the discharge tube 22 (discharge space 28), the starting rare gas (at room temperature under 20 atm) are enclosed together with the luminescent material (NaI, ScI _3, etc.).

  Of the pinch seal portions 24, 25, the conductor assembly 26 sealed (fixed) to the proximal-side pinch seal portion 24 has a tungsten conductor rod 26a and a molybdenum conductor rod 26c straight through a rectangular molybdenum foil 26b. Connected and integrated. The tip of the molybdenum conductor rod 26c is press-fitted into the inner conductor 19 and connected to the inner conductor 19, and a portion of the tungsten conductor rod 26a projects into the discharge space 28 by a predetermined length. ing.

  On the other hand, the conductor assembly 27 sealed (fixed) to the tip side pinch seal portion 25 is integrated by connecting a tungsten conductor rod 27a and a molybdenum conductor rod 27c in a straight line via a rectangular molybdenum foil 27b. Has been. A portion of the molybdenum conductor rod 27c is exposed to the outside, and a portion of the tungsten conductor rod 27a projects into the discharge space 28 by a predetermined length.

  The tungsten conductor rods 26a, 27a constituting the conductor assemblies 26, 27 are made of, for example, a potassium-doped tungsten wire or a tria-doped tungsten wire having an outer diameter of 0.25 mm, and the molybdenum foils 26b, 27b are, for example, 20 μm thick. Is formed. Molybdenum foils 26b and 27b are familiar with glass, and the thermal expansion difference between the glass (quartz glass) layer and the conductor assemblies 26 and 27 in the pinch seal portions 24 and 25 is absorbed by the molybdenum foils 26b and 27b. . For this reason, generation | occurrence | production of the crack in the pinch seal parts 24 and 25 is suppressed, and non-lighting can be prevented.

  Further, since the cross-sectional area of the molybdenum foils 26b and 27b is smaller than the cross-sectional area of the tungsten conductor rods 26a and 27a, the heat conduction of the conductor assemblies 25 and 26 as a whole is suppressed, and the heat conduction in the conductor assemblies 26 and 27 is suppressed. The loss due to can be reduced.

  When the molybdenum conductor rod 26c of the base end side pinch seal portion 24 of the discharge tube 22 is press-fitted into the internal conductor 19 of the electromagnetic wave irradiation portion 18, the pinch seal portion 24 is gripped (clamped) by the internal conductor 19 and the shaft The distal end portion of the molybdenum conductor rod 26c and the longitudinal end portion of the internal conductor 19 are electrically connected.

  For this reason, the high frequency electromagnetic wave transmitted from the power supply unit 12 to the electromagnetic wave transmission unit 14 is generated in the discharge space 28 by the conductor assembly 26 sealed to the base end side pinch seal unit 24 and the external conductor 20 surrounding the conductor assembly 26. Is irradiated. At this time, the irradiated electromagnetic wave (high-frequency electric field generated in the electromagnetic wave irradiation unit 18) generates high-density plasma in the discharge space 28, and the luminescent substance in the discharge space 28 is evaporated and excited to emit light. .

  In this case, since the tungsten conductor rod 26a of the conductor assembly 26 constituting the electromagnetic wave irradiation unit 18 protrudes into the discharge space 28, the electromagnetic wave transmitted by the electromagnetic wave transmission unit 14 is surely discharged through the conductor rod 26a. It is introduced into the space 28.

  The conductor assembly 27 sealed to the tip side pinch seal portion 25 of the discharge tube 22 acts as an antenna, and a high electric field concentrates around the conductor assembly 27, so that the arc converges toward the conductor assembly 27. The arc (shape) is stable. In particular, when used as a light source for automotive lamps such as headlamps, the discharge tube 22 is used in a horizontal lighting form, but since the arc (shape) is stable, the arc does not come into contact with the tube wall so as to have an optimum shape. The shape of the discharge tube 22 (tube wall) can be designed, leading to an improvement in luminous efficiency.

  Here, when electromagnetic waves generated from the power supply unit 12 are transmitted through the electromagnetic wave transmission unit 14 and the electromagnetic wave irradiation unit 18, if the characteristic impedances of the electromagnetic wave transmission unit 14 and the electromagnetic wave irradiation unit 18 do not match, the characteristic impedance discontinuity portion (characteristic A reflected wave is generated at a portion where the impedance does not match, and the electromagnetic wave does not efficiently reach the discharge tube 22, and as a result, the efficiency (lm / W) of the discharge tube 22 decreases.

  That is, in order to increase the efficiency of the discharge tube 22, the characteristic impedance of the transmission path from the power supply unit 12 to the discharge tube 22 may be made uniform.

  In general, the characteristic impedance of the coaxial pipe or coaxial cable constituting the electromagnetic wave transmission unit is 50Ω or 75Ω, and the output impedance of the power source is also matched to the characteristic impedance of the electromagnetic wave transmission unit. Without being able to transmit the electromagnetic wave transmission part.

  Therefore, since the output impedance of the power supply unit 12 is matched to the characteristic impedance of the electromagnetic wave transmission unit 14, in order to increase the efficiency of the discharge tube 22, the connection between the electromagnetic wave transmission unit 14 and the electromagnetic wave irradiation unit 18 and the electromagnetic wave The characteristic impedance of the irradiating unit 18 is not limited to 50Ω or 75Ω.

The characteristic impedance Zo of the transmission line such as the electromagnetic wave transmission unit 14 is as follows:
Zo = 138 / √ε × log (D / d) (1)
However,
Zo: Characteristic impedance (50Ω or 75Ω)
ε: dielectric constant
D: Inner diameter of outer conductor d: Outer diameter of inner conductor

  Here, based on the formula (1), the ratio D / d between the inner diameter D of the outer conductor 20 and the outer diameter d of the inner conductor 19 in the electromagnetic wave irradiation unit 18 is optimized, and the electromagnetic wave transmission unit 14 and the electromagnetic wave irradiation unit 18. In order to perform impedance matching, various measurements of power transmission loss were performed using the dielectric constant ε and the ratio D / d, which are the materials of the heat insulating member (spacer 21), as parameters. As shown in FIGS. Results were obtained.

  FIG. 2 is a measurement result when the output impedance Zo of the power supply unit 12 is 50Ω. Since the transmission loss is 3 W when the reflection detecting means and the output adjusting means are used, the case where the reflection loss is 3 W or less is shown. “○” indicates a case where the reflection loss exceeds 3 W by “×”.

  (A) When the heat insulating member is air (ε≈1.0), when D / d = 1.1, the reflection loss exceeds 3 W, whereas when D / d = 1.5, the reflection is reflected. Loss is 3W or less.

  (B) When the heat insulating member is made of foamed Teflon (registered trademark) (ε = 1.8 to 2.1), when D / d = 2.0, the reflection loss becomes 3 W or less.

  (C) When the heat insulating member is quartz (ε = 3.5 to 4.5), the reflection loss is 3 W or less when D / d = 5.0.

(D) When the heat insulating member is alumina (ε = 8.0 to 10.0), if D / d = 10.0, 20.0, 30.0, 40.0, the reflection loss is reduced. On the other hand, when D / d = 50.0, the reflection loss exceeds 3W.
On the other hand, FIG. 3 shows the measurement results when the output impedance Zo of the power supply unit 12 is 75Ω, and “○” indicates that the reflection loss is 3 W or less, and “X” indicates that the reflection loss exceeds 3 W. It is.

  (A) When the heat insulating member is air (ε≈1.0), when D / d = 1.1, the reflection loss exceeds 3 W, whereas D / d = 1.5, or 2. When 0 is set, the reflection loss is 3 W or less.

  (B) When the heat insulating member is made of foamed Teflon (registered trademark) (ε = 1.8 to 2.1), when D / d = 5.0, the reflection loss becomes 3 W or less.

  (C) When the heat insulating member is made of quartz (ε = 3.5 to 4.5), if D / d = 10.0, the reflection loss becomes 3 W or less.

  (D) When the heat insulating member is alumina (ε = 8.0 to 10.0), if D / d = 20.0, 30.0, or 40.0, the reflection loss becomes 3 W or less. On the other hand, when D / d = 50.0, the reflection loss exceeds 3W.

  From the measurement results shown in FIGS. 2 and 3, considering that the output impedance Zo of the power supply unit 12 is 50Ω or 75Ω, D / d satisfies the relationship of 1.5 ≦ D / d ≦ 40, and ε is If the relationship of 1 ≦ ε ≦ 10 is satisfied, the electromagnetic wave transmission unit 14 and the electromagnetic wave irradiation unit 18 have impedance matching (matching) with each other, the reflection loss can be reduced to 3 W or less, and the efficiency associated with transmission of the electromagnetic wave It can be seen that it is possible to suppress the decrease of the.

  In this case, when the spacer (heat insulating member) 21 is air, D / d is 1.5 ≦ D / d ≦ 2.0, and when the spacer 21 is foamed Teflon (registered trademark), D / d is 2 When 0.0 ≦ D / d ≦ 5.0 and the spacer 21 is quartz, D / d is 5.0 ≦ D / d ≦ 10.0, and when the spacer 21 is alumina, D / d is 10 0.0 ≦ D / d ≦ 40.0.

  That is, by adjusting D / d according to the dielectric constant ε of the spacer (heat insulating member) 21, even if the output impedance of the power supply unit 12 is 50Ω or 75Ω, the electromagnetic wave transmission unit 14 and the electromagnetic wave irradiation unit 18 Impedance matching can be performed.

  According to the present embodiment, the ratio D / d between the inner diameter D of the outer conductor 20 and the outer diameter d of the inner conductor 19 in the electromagnetic wave irradiation unit 18 is optimized according to the value of the dielectric constant ε, Since the impedance matching is made between the electromagnetic wave irradiation unit 18 and the reflected wave detecting means for detecting the reflected wave propagating from the discharge tube 22 to the power supply unit 12 side, or the reflection loss based on the reflected wave detected by the reflected wave detecting means. Without providing an output adjustment means for adjusting the output of the power supply unit 12 to minimize the power consumption, it is possible to suppress a decrease in efficiency associated with the transmission of electromagnetic waves and to simplify the configuration.

  Further, according to the present embodiment, the spacer 21 as the heat insulating member is made of quartz glass, alumina, or Teflon (registered trademark), which is a discharge preventing material, so that the space between the inner conductor 19 and the outer conductor 20 is increased. The discharge tube 22 can be prevented from being discharged, and the discharge tube 22 can be prevented from being unlit due to the discharge between the inner conductor 19 and the outer conductor 20.

  Next, a second embodiment of the present invention will be described with reference to FIG. In this embodiment, an electromagnetic wave transmission unit 34 is used instead of the electromagnetic wave transmission unit 14, an electromagnetic wave irradiation unit 38 is used instead of the electromagnetic wave irradiation unit 18, and a discharge tube 42 is used instead of the discharge tube 22. There are other configurations similar to those of the first embodiment.

  Specifically, the electromagnetic wave transmission unit 34 includes a metal columnar inner conductor 35, a metal circular pipe-shaped outer conductor 36 surrounding the inner conductor 35, and a circular pipe shape. An insulating member interposed between the outer conductor 36, for example, a quartz glass dielectric 37 is coaxially integrated, for example, configured as a coaxial tube or a coaxial cable, and the inner conductor 35 and this Electromagnetic waves are transmitted between the outer conductors 36 surrounding the.

  The electromagnetic wave irradiation unit 38 includes a metal columnar inner conductor 39 and a metal outer conductor 40 that is formed in a substantially hollow cylindrical shape and surrounds the inner conductor 39, and between the inner conductor 39 and the outer conductor 40, As a heat insulating member, a glass tube (quartz glass) 41 extended from the concave portion 44a of the pinch seal portion 44 is interposed, and a longitudinal end portion of the internal conductor 39 serves as a launcher for introducing electromagnetic waves into the discharge tube 42. The discharge tube 42 is connected to the longitudinal end portion.

  The internal conductor 39 is connected to the internal conductor 35 of the electromagnetic wave transmission unit 34 and is disposed from the longitudinal end of the internal conductor 35 to the longitudinal end of the external conductor 40. An annular step 40a is formed on one end in the longitudinal direction of the outer conductor 40, and a cylindrical cover 32 is mounted on the other end in the longitudinal direction. The step 40a is connected to the outside of the electromagnetic wave transmission unit 34. One end side in the longitudinal direction of the conductor 36 is press-fitted. That is, the outer conductor 36 and the outer conductor 40 are electrically connected via the step 40a. The cover 32 has an opening 32a through which the discharge tube 42 is inserted.

The discharge tube 42 pinch-seals both ends of a glass (anhydrous quartz glass) tube having an elliptical spherical bulge 43 formed in the middle in the longitudinal direction, so that the conductor assemblies 46 and 47 are attached to the pinch seals 44 and 45. It is sealed and has a double end type in which the inside of the oval bulge 43 is a discharge space 48. Then, in the elliptical spherical bulging portion 43 (discharge space 48) of the discharge tube 42, a starting rare gas (1 to 20 atm under normal temperature) is enclosed together with a luminescent material (NaI, ScI ₃ or the like).

  Of the pinch seal portions 44 and 45, the proximal end side pinch seal portion 44 is inserted into the external conductor 40 through the opening 32 a of the cover 32. The conductor assembly 46 sealed (fixed) to the proximal pinch seal portion 44 is integrated by connecting a tungsten conductor rod 46a and a molybdenum conductor rod 46c in a straight line via a rectangular molybdenum foil 46b. ing.

  A part of the tungsten conductor rod 46 a protrudes into the discharge space 48 by a predetermined length. A portion of the molybdenum conductor rod 46 c is exposed in the recess 44 a of the pinch seal portion 44. The inner conductor 39 has a longitudinal end connected to the longitudinal end of the molybdenum conductor rod 46c. That is, the conductor assembly 46 is electrically connected to the inner conductor 39 of the electromagnetic wave irradiation unit 38.

  On the other hand, the conductor assembly 47 sealed (fixed) to the tip side pinch seal portion 45 is integrated by connecting a tungsten conductor rod 47a and a molybdenum conductor rod 47c in a straight line via a rectangular molybdenum foil 47b. Has been. A portion of the tungsten conductor rod 47 a protrudes into the discharge space 48 by a predetermined length, and a portion of the molybdenum conductor rod 47 c is exposed in the recess 45 a of the pinch seal portion 45. .

  The tungsten conductor rods 46a, 47a constituting the conductor assemblies 46, 47 are made of, for example, a potassium-doped tungsten wire or a tria-doped tungsten wire having an outer diameter of 0.25 mm, and the molybdenum foils 46b, 47b are, for example, 20 μm thick. Is formed. Molybdenum foils 46b and 47b are familiar with glass, and the thermal expansion difference between the glass (quartz glass) layer and the conductor assemblies 46 and 47 in the pinch seal portions 44 and 45 is absorbed by the molybdenum foils 46b and 47b. . For this reason, generation | occurrence | production of the crack in the pinch seal parts 44 and 45 is suppressed, and a non-lighting can be prevented.

  Further, since the cross-sectional area of the molybdenum foils 46b and 47b is smaller than the cross-sectional area of the tungsten conductor rods 46a and 47a, the heat conduction of the conductor assemblies 45 and 46 as a whole is suppressed, and the heat conduction in the conductor assemblies 46 and 47 is suppressed. The loss due to can be reduced.

  When the distal end portion of the proximal-side pinch seal portion 44 of the discharge tube 42 is inserted into the external conductor 40 of the electromagnetic wave irradiation portion 38 from the opening 32 a of the cover 32, the pinch seal portion 44 is gripped (clamped) by the cover 32. Thus, the distal end portion of the molybdenum conductor rod 46c and the longitudinal end portion of the internal conductor 39 are electrically connected.

  For this reason, the high-frequency electromagnetic wave transmitted from the power supply unit 12 through the electromagnetic wave transmission unit 34 is generated in the discharge space 48 by the conductor assembly 46 sealed by the base end side pinch seal unit 44 and the external conductor 40 surrounding the conductor assembly 46. Is irradiated. At this time, the irradiated electromagnetic wave (the high frequency electric field generated in the electromagnetic wave irradiation unit 38) generates high-density plasma in the discharge space 48, and the luminescent substance in the discharge space 48 is evaporated and excited to emit light. .

  In this case, since the tungsten conductor rod 46a of the conductor assembly 46 constituting the electromagnetic wave irradiation unit 38 protrudes into the discharge space 48, the electromagnetic wave transmitted by the electromagnetic wave transmission unit 34 is surely discharged through the conductor rod 46a. It is introduced into the space 48.

  The conductor assembly 47 sealed to the tip side pinch seal portion 45 of the discharge tube 42 acts as an antenna, and a high electric field is concentrated around the conductor assembly 47, so that the arc converges toward the conductor assembly 47. The arc (shape) is stable. In particular, when used as a light source for an automotive lamp such as a headlamp, the discharge tube 42 is used in a horizontal lighting form. However, since the arc (shape) is stable, the arc does not come into contact with the tube wall so as to have an optimum shape. The shape of the discharge tube 42 (tube wall) can be designed, leading to an improvement in luminous efficiency.

  In this embodiment, in order to optimize the ratio D / d between the inner diameter D of the outer conductor 40 and the outer diameter d of the inner conductor 39 in the electromagnetic wave irradiation unit 38, the electromagnetic wave transmission unit 34 and the electromagnetic wave irradiation unit 38 are impedance matched. When various measurements were performed on the power transmission loss using ε and D / d, which are the materials of the heat insulating member (quartz glass 41), as parameters, the same results as in the first example were obtained.

  According to this embodiment, the ratio D / d between the inner diameter D of the outer conductor 40 and the outer diameter d of the inner conductor 39 in the electromagnetic wave irradiation unit 38 is optimized according to the value of the dielectric constant ε, Since the impedance matching is performed with the electromagnetic wave irradiation unit 38, the reflection loss is detected based on the reflected wave detecting means for detecting the reflected wave propagating from the discharge tube 42 to the power supply unit 12, and the reflected wave detected by the reflected wave detecting means. Without providing an output adjustment means for adjusting the output of the power supply unit 12 to minimize the power consumption, it is possible to suppress a decrease in efficiency associated with the transmission of electromagnetic waves and to simplify the configuration.

  Next, a third embodiment of the present invention will be described with reference to FIG. In this embodiment, instead of the discharge tube 42, a discharge tube 52 having a partially different configuration of the pinch seal portion and the conductor assembly is used from the discharge tube 42, and the other configuration is the same as that of the second embodiment. is there.

Specifically, in the discharge tube 52, conductor assemblies 56 and 57 are sealed to pinch seal portions 54 and 55 formed on both ends of the elliptic spherical bulge portion 53, and the inside of the elliptic spherical bulge portion 53 is discharged. The space 58 is a double-ended type. Then, in the discharge space 58 of the discharge tube 52, starting rare gas (at room temperature under 20 atm) it is enclosed together with the luminescent material (NaI, ScI _3, etc.).

  The proximal end side pinch seal portion 54 is inserted into the opening 32 a of the cover 32 at the proximal end side. The conductor assembly 56 sealed (fixed) to the proximal-side pinch seal portion 54 is integrated by connecting a tungsten conductor rod 56a and a molybdenum conductor rod 56c in a straight line via a rectangular molybdenum foil 56b. ing. The molybdenum conductor rod 56 c has a tip portion protruding from the recess 54 a of the pinch seal portion 54 and inserted into the outer conductor 40 of the electromagnetic wave irradiation portion 38, and a longitudinal end portion is a longitudinal end of the internal conductor 35. Connected to the department. Further, a cylindrical alumina spacer 51 disposed between the molybdenum conductor rod 56c and the outer conductor 40 is mounted on the outer peripheral side of the molybdenum conductor rod 56c as a heat insulating member.

  On the other hand, the conductor assembly 57 sealed (fixed) to the tip side pinch seal portion 55 is integrated by connecting a tungsten conductor rod 57a and a molybdenum conductor rod 57c in a straight line via a rectangular molybdenum foil 57b. Has been. A portion of the tungsten conductor rod 57a protrudes into the discharge space 58 by a predetermined length, and a portion of the molybdenum conductor rod 57c is exposed in the recess 55a of the pinch seal portion 55. .

  Then, the molybdenum conductor rod 56c of the conductor assembly 56 and the alumina spacer 51 are inserted into the outer conductor 40 of the electromagnetic wave irradiation unit 38 from the opening 32a of the cover 32, and the distal end portion of the base end side pinch seal portion 54 is the opening 32a of the cover 32. When inserted, the alumina spacer 51 is gripped by the outer conductor 40, the pinch seal portion 44 is gripped (clamped) by the cover 32, and is positioned and fixed in the axial direction and the circumferential direction. The distal end portion and the longitudinal end portion of the internal conductor 35 are electrically connected.

  For this reason, the high-frequency electromagnetic wave transmitted from the power supply unit 12 through the electromagnetic wave transmission unit 34 is generated in the discharge space 58 by the conductor assembly 56 sealed to the proximal end pinch seal unit 54 and the external conductor 40 surrounding the conductor assembly 56. Is irradiated. At this time, the irradiated electromagnetic wave (high-frequency electric field generated in the electromagnetic wave irradiation unit 38) generates high-density plasma in the discharge space 58, and the luminescent substance in the discharge space 58 is evaporated and excited to emit light. .

  In this embodiment, the ratio D / d between the inner diameter D of the outer conductor 40 and the outer diameter d of the molybdenum conductor rod 56c in the electromagnetic wave irradiation unit 38 is optimized, and the electromagnetic wave transmission unit 34 and the electromagnetic wave irradiation unit 38 are impedance matched. Therefore, various measurements were performed on power transmission loss using ε and D / d, which are materials of the heat insulating member (alumina spacer 51), as parameters, and the same results as in the first example were obtained.

  According to the present embodiment, the ratio D / d between the inner diameter D of the outer conductor 40 and the outer diameter d of the molybdenum conductor rod 56c in the electromagnetic wave irradiation section 38 is optimized according to the value of the dielectric constant ε, and the electromagnetic wave transmission section 34 and the electromagnetic wave irradiation unit 38 are impedance-matched, so that the reflected wave detecting means for detecting the reflected wave propagating from the discharge tube 52 to the power supply unit 12 side or the reflected wave detected by the reflected wave detecting means is used as a basis. Without providing an output adjusting means for adjusting the output of the power supply unit 12 to minimize the reflection loss, it is possible to suppress a decrease in efficiency associated with the transmission of electromagnetic waves and to simplify the configuration.

  Next, a fourth embodiment of the present invention will be described with reference to FIG. In this embodiment, instead of the discharge tube 42, a discharge tube 62 having a partially different configuration of the pinch seal portion from the discharge tube 42 is used, and other configurations are the same as those of the second embodiment.

Specifically, in the discharge tube 62, conductor assemblies 66 and 67 are sealed to pinch seal portions 64 and 65 formed on both ends of the elliptic spherical bulging portion 63, and the inside of the elliptic spherical bulging portion 63 is discharged. The space 68 is a double-ended type. Then, in the discharge space 68 of the discharge tube 62, starting rare gas (at room temperature under 20 atm) it is enclosed together with the luminescent material (NaI, ScI _3, etc.).

  A quartz spacer 61 is integrally formed on the distal end side of the proximal-side pinch seal portion 64 so as to fill a space between the outer conductor 40 and the inner conductor 39 of the electromagnetic wave irradiation unit 38. Has been inserted inside. The conductor assembly 66 sealed (fixed) to the base-side pinch seal portion 64 is integrated by connecting a tungsten conductor rod 66a and a molybdenum conductor rod 66c in a straight line via a rectangular molybdenum foil 66b. ing.

  A part of the tungsten conductor rod 66 a protrudes into the discharge space 68 by a predetermined length. A portion of the molybdenum conductor rod 66 c is exposed in the recess 64 a of the pinch seal portion 64. The inner conductor 39 has an outer diameter substantially equal to the outer diameter of the inner conductor 35, one end in the longitudinal direction is connected to the end in the longitudinal direction of the inner conductor 35, and the other end in the longitudinal direction is connected to the end in the longitudinal direction of the molybdenum conductor rod 66c. It is connected. That is, the conductor assembly 66 is electrically connected to the internal conductor 35 of the electromagnetic wave irradiation unit 38 via the internal conductor 39.

  On the other hand, the conductor assembly 67 sealed (fixed) to the tip side pinch seal portion 65 is integrated by connecting a tungsten conductor rod 67a and a molybdenum conductor rod 67c in a straight line via a rectangular molybdenum foil 67b. Has been. A portion of the tungsten conductor rod 67a protrudes into the discharge space 68 by a predetermined length, and a portion of the molybdenum conductor rod 67c is exposed in the recess 65a of the pinch seal portion 65. .

  Then, the quartz spacer 61 on the distal end side of the proximal end side pinch seal portion 64 of the discharge tube 62 is inserted into the outer conductor 40 of the electromagnetic wave irradiation portion 38, and the cover 32 is attached to the end portion of the outer conductor 40, and the proximal end side pinch When a part of the seal portion 64 is inserted into the opening 32a of the cover 32, the quartz spacer 61 is gripped by the outer conductor 40, and the pinch seal portion 64 is gripped (clamped) by the cover 32 so as to be axially and circumferentially. In addition to being positioned and fixed, the distal end portion of the internal conductor 39 and the longitudinal end portion of the internal conductor 35 are electrically connected.

  For this reason, the high frequency electromagnetic wave transmitted from the power supply unit 12 through the electromagnetic wave transmission unit 34 is generated in the discharge space 68 by the conductor assembly 66 sealed by the base end side pinch seal unit 64 and the external conductor 40 surrounding the conductor assembly 66. Is irradiated. At this time, the irradiated electromagnetic wave (high-frequency electric field generated in the electromagnetic wave irradiation unit 38) generates high-density plasma in the discharge space 68, and the luminescent substance in the discharge space 68 is evaporated and excited to emit light. .

  In this embodiment, in order to optimize the ratio D / d between the inner diameter D of the outer conductor 40 and the outer diameter d of the inner conductor 39 in the electromagnetic wave irradiation unit 38, the electromagnetic wave transmission unit 34 and the electromagnetic wave irradiation unit 38 are impedance matched. In addition, various measurements were performed on the power transmission loss using ε and D / d, which are materials of the heat insulating member (quartz spacer 61), as parameters, and the same results as in the first example were obtained.

  According to this embodiment, the ratio D / d between the inner diameter D of the outer conductor 40 and the outer diameter d of the inner conductor 39 in the electromagnetic wave irradiation unit 38 is optimized according to the value of the dielectric constant ε, Since the impedance matching is made between the electromagnetic wave irradiation unit 38 and the reflected wave detecting means for detecting the reflected wave propagating from the discharge tube 52 to the power supply unit 12, the reflection loss is based on the reflected wave detected by the reflected wave detecting means. Without providing an output adjustment means for adjusting the output of the power supply unit 12 to minimize the power consumption, it is possible to suppress a decrease in efficiency associated with the transmission of electromagnetic waves and to simplify the configuration.

  Next, a fifth embodiment of the present invention will be described with reference to FIG. In this embodiment, instead of the discharge tube 42, a shroud-equipped discharge tube 72 having a partially different configuration of the pinch seal portion and the conductor assembly from the discharge tube 42 is used, and the other configuration is the same as that of the second embodiment. It is the same.

Specifically, the discharge tube 72 with a shroud includes conductor assemblies 76 and 77 sealed to pinch seal portions 74 and 75 formed on both ends of the elliptic spherical bulge portion 73, and Is formed into a double-end type in which a discharge space 78 is formed. Cylindrical ultraviolet shielding shrouds 79 that surround the pinch seal portions 74 and 75 are welded to both ends of the pinch seal portions 74 and 75. . Then, in the discharge space 78 of the discharge tube 72, starting rare gas (at room temperature under 20 atm) it is enclosed together with the luminescent material (NaI, ScI _3, etc.).

  A quartz spacer 71 is integrally formed on the distal end side of the base end side pinch seal portion 74 so as to fill a space between the outer conductor 40 and the inner conductor 39 of the electromagnetic wave irradiation unit 38. This quartz spacer (quartz glass) 71 is integrally formed. Is inserted into the outer conductor 40. The conductor assembly 76 sealed (fixed) to the proximal pinch seal portion 74 is integrated by connecting a tungsten conductor rod 76a and a molybdenum conductor rod 76c in a straight line via a rectangular molybdenum foil 76b. ing. A portion of the molybdenum conductor rod 76 c is exposed in the recess 74 a of the pinch seal portion 74, and the tip side protrudes from the recess 74 a and is connected to the longitudinal end of the internal conductor 39.

  On the other hand, the conductor assembly 77 sealed (fixed) to the tip side pinch seal portion 75 is integrated by connecting a tungsten conductor rod 77a and a molybdenum conductor rod 77c in a straight line via a rectangular molybdenum foil 77b. Has been. A portion of the tungsten conductor rod 77a protrudes into the discharge space 78 by a predetermined length, and a portion of the molybdenum conductor rod 77c is exposed in the recess 75a of the pinch seal portion 75. .

  The shroud 79 is made of quartz glass added with a metal such as titanium which has an ultraviolet ray blocking action harmful to the human body, and cuts ultraviolet rays harmful to the human body included in the discharge light emission of the discharge tube 72. There is an effect.

  That is, if the discharge tube 72 is made of quartz glass to which a metal having an ultraviolet ray-cutting effect is added, the heat resistance temperature of the glass tube is lowered, and the reaction is caused by the reaction between the added metal and the encapsulated substance (effect on light emission). Since this is not possible, the discharge tube 72 is made of anhydrous quartz glass having no ultraviolet ray blocking action. In order to avoid damage to the resin lamp components and the adverse effect on the human body due to the radiation of ultraviolet rays, the elliptical spherical bulging portion 73 of the discharge tube 72 is covered with a shroud 79 for shielding ultraviolet rays.

In addition, it is also effective to add alumina (Al ₂ O ₃ ) to the quartz glass constituting the shroud 79 in order to prevent deterioration of working characteristics due to Na loss.

  Further, since the inside of the shroud 79 (around the discharge tube 72) is a sealed space 80 filled with an inert gas or evacuated, the sealed space 80 in which heat radiation from the discharge tube 72 is a heat insulating layer. The luminous efficiency of the discharge tube 72 can be improved.

The inert gas or the like to be enclosed in the shroud 79 (sealed space 80) is preferably one having higher heat insulation than air. For example, N ₂ , Xe or Ar simple gas is sealed, or N ₂ + Ar , N ₂ + Xe, Ar + Ne or the like may be encapsulated.

  Then, the distal end side of the proximal end side pinch seal portion 74 of the discharge tube 72 and the quartz spacer 71 are inserted into the outer conductor 40 of the electromagnetic wave irradiation portion 38, and the cover 32 is attached to the end portion of the outer conductor 40, and the proximal end side pinch When a part of the seal portion 74 is inserted into the opening 32a of the cover 32, the quartz spacer 71 is gripped by the outer conductor 40, and the pinch seal portion 74 is gripped (clamped) by the cover 32 so as to be axially and circumferentially. In addition to being positioned and fixed, the distal end portion of the internal conductor 39 and the longitudinal end portion of the internal conductor 35 are electrically connected.

  For this reason, the high frequency electromagnetic wave transmitted from the power supply unit 12 through the electromagnetic wave transmission unit 34 is generated in the discharge space 78 by the conductor assembly 76 sealed by the proximal end pinch seal unit 74 and the outer conductor 40 surrounding the conductor assembly 76. Is irradiated. At this time, the irradiated electromagnetic wave (the high frequency electric field generated in the electromagnetic wave irradiation unit 38) generates high-density plasma in the discharge space 78, and the luminescent substance in the discharge space 78 is evaporated and excited to emit light. .

  In this embodiment, in order to optimize the ratio D / d between the inner diameter D of the outer conductor 40 and the outer diameter d of the inner conductor 39 in the electromagnetic wave irradiation unit 38, the electromagnetic wave transmission unit 34 and the electromagnetic wave irradiation unit 38 are impedance matched. In addition, when various measurements were performed on the power transmission loss using ε and D / d, which are materials of the heat insulating member (quartz glass 71), as parameters, the same results as in the first example were obtained.

  According to this embodiment, the ratio D / d between the inner diameter D of the outer conductor 40 and the outer diameter d of the inner conductor 39 in the electromagnetic wave irradiation unit 38 is optimized according to the value of the dielectric constant ε, Since the impedance matching is performed between the electromagnetic wave irradiation unit 38 and the reflected wave detection means for detecting the reflected wave propagating from the discharge tube 72 to the power supply unit 12 side, or the reflection loss based on the reflected wave detected by the reflected wave detection means. Without providing an output adjustment means for adjusting the output of the power supply unit 12 to minimize the power consumption, it is possible to suppress a decrease in efficiency associated with the transmission of electromagnetic waves and to simplify the configuration.

  Next, a sixth embodiment of the present invention will be described with reference to FIG. In this embodiment, instead of the discharge tube 42, a discharge tube 92 having a partially different configuration and a different material for the pinch seal portion and the conductor assembly from the discharge tube 42 is used, and an electromagnetic wave irradiation unit is used instead of the electromagnetic wave irradiation unit 38. 38 is an electromagnetic wave irradiation unit 138 having a partially different configuration of the outer conductor, and the other configuration is the same as that of the second embodiment.

  Specifically, the electromagnetic wave irradiation part 138 is formed in a substantially hollow cylindrical shape and includes a metal outer conductor 140 surrounding the sealing part 94, and the discharge tube 92 is interposed between the conductor assembly 96 and the outer conductor 140. A conductor assembly 96 of the discharge tube 92 is disposed in the external conductor 140 as a launcher for introducing an electromagnetic wave into the discharge tube 92 with a partially constructed ceramic 141 as a heat insulating member.

  An annular step 140a is formed on one end in the longitudinal direction of the outer conductor 140, and one end in the longitudinal direction of the outer conductor 36 of the electromagnetic wave transmission unit 34 is press-fitted into the step 140a. That is, the outer conductor 36 and the outer conductor 140 are electrically connected via the stepped portion 140a.

The discharge tube 92 is configured as a ceramic HID (High Intensity Discharge), and conductor assemblies 96 and 97 are sealed to sealing portions 94 and 95 formed at both ends of the ceramic oval spherical bulge portion 93, And the inside of the elliptical spherical bulging part 93 is comprised by the double end type by which the discharge space 98 was made. Then, in the discharge tube 92 discharge space 98, starting rare gas (at room temperature under 20 atm) are enclosed together with the luminescent material (NaI, ScI _3, etc.).

  The proximal end side sealing portion 94 has a distal end portion inserted into the outer conductor 140. The conductor assembly 96 sealed (fixed) to the base end side sealing portion 94 has one end in the longitudinal direction protruding by a predetermined length into the discharge space 98 and the other end in the longitudinal direction is the end in the longitudinal direction of the internal conductor 35. It is connected to the. That is, the conductor assembly 96 is electrically connected to the inner conductor 35 of the electromagnetic wave transmission unit 34.

  On the other hand, the conductor assembly 97 sealed (fixed) to the front end side sealing portion 95 has one end in the longitudinal direction protruding into the discharge space 98 by a predetermined length, and a part on the other end in the longitudinal direction is exposed to the outside. Has been.

  When the distal end side of the sealing portion 94 is inserted into the external conductor 140, the sealing portion 94 is gripped by the external conductor 140 and positioned and fixed in the axial direction and the circumferential direction. The distal end portion of the assembly 96 and the longitudinal end portion of the inner conductor 35 are electrically connected.

  For this reason, the high frequency electromagnetic wave transmitted from the power supply unit 12 through the electromagnetic wave transmission unit 34 is generated in the discharge space 98 by the conductor assembly 96 sealed to the base end side sealing unit 94 and the external conductor 140 surrounding the conductor assembly 96. Is irradiated. At this time, the irradiated electromagnetic wave (high-frequency electric field generated in the electromagnetic wave irradiation unit 138) generates high-density plasma in the discharge space 98, and the luminescent substance in the discharge space 98 is evaporated and excited to emit light. .

  In this embodiment, in order to optimize the ratio D / d between the inner diameter D of the outer conductor 140 and the outer diameter d of the conductor assembly 96 in the electromagnetic wave irradiation unit 138, the electromagnetic wave transmission unit 34 and the electromagnetic wave irradiation unit 138 are impedance matched. In addition, various measurements were performed on power transmission loss using ε and D / d, which are materials of the heat insulating member (ceramic 141), as parameters, and the same results as in the first example were obtained.

  According to this embodiment, the ratio D / d between the inner diameter D of the outer conductor 140 and the outer diameter d of the conductor assembly 96 in the electromagnetic wave irradiation unit 138 is optimized according to the value of the dielectric constant ε, Since the impedance matching is performed with the electromagnetic wave irradiation unit 138, the reflection loss is detected based on the reflected wave detecting means for detecting the reflected wave propagating from the discharge tube 92 to the power supply unit 12, and the reflected wave detected by the reflected wave detecting means. Without providing an output adjustment means for adjusting the output of the power supply unit 12 to minimize the power consumption, it is possible to suppress a decrease in efficiency associated with the transmission of electromagnetic waves and to simplify the configuration.

BRIEF DESCRIPTION OF THE DRAWINGS It is a block diagram including the principal part cross section of the high frequency discharge lamp system which shows 1st Example of this invention. It is a figure for demonstrating the relationship between a parameter and a reflection loss when the output impedance of a power supply is 50 ohms and the power transmission loss of an electromagnetic wave irradiation part is measured. It is a figure for demonstrating the relationship between the parameter and reflection loss when the output impedance of a power supply is 75 ohms and the power transmission loss of an electromagnetic wave irradiation part is measured. It is a block diagram including the principal part cross section of the high frequency discharge lamp system which shows 2nd Example of this invention. It is a block diagram including the principal part cross section of the high frequency discharge lamp system which shows 3rd Example of this invention. It is a block diagram including the principal part cross section of the high frequency discharge lamp system which shows 4th Example of this invention. It is a block diagram including the principal part cross section of the high frequency discharge lamp system which shows 5th Example of this invention. It is a block diagram including the principal part cross section of the high frequency discharge lamp system which shows 6th Example of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 High frequency discharge lamp system 12 Power supply part 14, 34 Electromagnetic wave transmission part 15, 35 Inner conductor 16, 36 Outer conductor 18, 38, 138 Electromagnetic wave irradiation part 19, 39, 139 Inner conductor 20, 40, 140 Outer conductor 21 Spacer 22, 42, 52, 62, 72, 92 discharge tubes

Claims (3)

Introduced by the electromagnetic wave irradiation unit, an electromagnetic wave transmission unit that transmits electromagnetic waves generated from the power supply unit, an electromagnetic wave transmission unit that transmits electromagnetic waves generated from the power supply unit, an electromagnetic wave irradiation unit that introduces and radiates electromagnetic waves transmitted from the electromagnetic wave transmission unit In a high-frequency discharge lamp system comprising a discharge tube that discharges light by plasma generated by receiving electromagnetic waves,
The electromagnetic wave irradiation unit includes an inner conductor that introduces electromagnetic waves, a cylindrical outer conductor that covers the inner conductor, and a heat insulating member that is interposed between the inner conductor and the outer conductor. When the diameter is d, the inner diameter of the outer conductor is D, and the dielectric constant of the heat insulating member is ε, D / d satisfies the relationship 1.5 ≦ D / d ≦ 40, and ε is 1 ≦ 1 A high frequency discharge lamp system characterized by satisfying a relation of ε ≦ 10.   2. The high frequency discharge lamp system according to claim 1, wherein the heat insulating member is made of a discharge preventing material.   3. The high-frequency discharge lamp system according to claim 1, wherein when the heat insulating member is air, the D / d is 1.5 ≦ D / d ≦ 2.0, and the heat insulating member is foamed Teflon (registered trademark). ), The D / d is 2.0 ≦ D / d ≦ 5.0, and when the heat insulating member is quartz glass, the D / d is 5.0 ≦ D / d ≦ 10.0. When the heat insulating member is alumina, the D / d satisfies 10.0 ≦ D / d ≦ 40.0.

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