JP2011014247A - Light source device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To emit a required and sufficient ultraviolet ray into a discharge vessel of a high-pressure discharge lamp, by starting discharge of a start-up light source at a low start-up voltage, thereby enhance startability.SOLUTION: A light source device includes the high-pressure discharge lamp (1) connected to a light-on circuit, and the start-up light source (3) for emitting the ultraviolet ray for enhancing start-up performance when starting light-on of the lamp, toward the discharge vessel (5) of the lamp (1), the start-up light source is formed of a discharge tube (18) for generating the ultraviolet ray by generating the discharge between an internal electrode (19) provided in an inside of a light emitting portion thereof, and an external electrode (20) provided in an outside of the discharge tube, by the start-up voltage impressed between the electrodes when starting up the light-on of the lamp, and at least one charge concentration part forming metal piece (29) is sealed separately from the internal electrode, in a light emitting portion (23a) thereof.

Description

  The present invention relates to a light source device used in a liquid crystal projector, a DLP projector, an illumination device, and the like.

  Light source devices for liquid crystal projectors and DLP projectors, which are required to be small and have a bright projected image, use a short arc type high-pressure mercury vapor discharge lamp that is small and can provide high-intensity light emission. The lamps of the type generally have problems that the cold start performance and the hot restrike restart performance are not good, so a start auxiliary light source is provided to improve the start performance. .

The light source device shown in FIG. 7 is provided with a discharge tube 80 that irradiates ultraviolet rays to the discharge vessel 54 of the lamp 51 when the high-pressure discharge lamp 51 is turned on (see Patent Document 1).
In the high-pressure discharge lamp 51, a pair of tungsten electrodes 56 and 56 are arranged at a central portion of an arc tube 52 made of a quartz glass tube so as to face each other with a short inter-electrode distance of about 1 mm. A discharge vessel 54 filled with a starting gas such as a halogen gas and an argon gas is formed, and a pair of electrodes 56, a metal foil 57, and an electrode lead 58 are sealed from the discharge vessel 54 to both ends of the arc tube 52. Electrode sealing portions 59R and 59L are formed and connected to the lighting circuit via electrode leads 58 and 58 protruding from the end surfaces of the electrode sealing portions 59R and 59L.
The high-pressure discharge lamp 51 is attached integrally with the reflecting mirror 81 by inserting one electrode sealing portion 59L through the bottom hole 83 opened at the bottom of the concave reflecting mirror 81 and turning on the lamp 51. A glow discharge tube 80 serving as a starting auxiliary light source for irradiating the discharge vessel 54 with ultraviolet rays for enhancing the starting performance at the start is provided.

  The glow discharge tube 80 includes a pair of lead wires protruding from both ends of the glass sealed tube 84 while a rare gas such as argon gas containing mercury vapor is sealed inside the glass sealed tube 84 made of quartz glass. An internal electrode 85 made of a metal foil having 86 and 86 is housed and disposed, and a coil-like shape formed by winding a chromium-aluminum iron alloy wire 89 having a wire diameter of about 0.2 mm around the outer periphery of the glass sealed tube 84. Since the external electrode 87 is provided in a simple structure, there is an advantage that the manufacturing cost is not increased.

  The internal electrode 85 and the external electrode 87 of the glow discharge tube 80 are connected to the one electrode side 88R and the other electrode side 88L of the lamp lighting circuit, respectively, and the starting electrode is interposed between the internal electrode 85 and the external electrode 87. By applying the high frequency pulse voltage, glow discharge is generated in the mercury vapor in the glass sealed tube 84 which is the main body of the discharge tube 80 to generate ultraviolet rays, and a part of the ultraviolet rays is provided in the reflecting mirror 81. In addition, the discharge container 54 of the lamp 51 disposed inside the reflecting mirror 81 is directly irradiated through the ventilation hole 82 of the cooling air, or is reflected and reflected by the reflecting surface of the reflecting mirror 81.

However, when the coil-shaped external electrode 87 is provided on the outer peripheral portion thereof, if the number of turns of the coil is small, the amount of ultraviolet rays generated from the discharge tube 80 is small, so that it is necessary and sufficient toward the discharge vessel 54 of the lamp 51. If the number of turns of the coil-shaped external electrode 87 is increased, the external electrode 87 blocks the ultraviolet light, and the discharge vessel 54 of the lamp 51 has a necessary and sufficient amount. There is also a problem that ultraviolet rays cannot be irradiated.
Recently, further improvement in startability has been demanded, and it has been required to irradiate ultraviolet rays from the discharge tube 80 at a lower start voltage.

Registered Utility Model No. 3137961

  It is a technical object of the present invention to improve startability by irradiating a discharge vessel of a high-pressure discharge lamp with a necessary and sufficient amount of ultraviolet rays by starting discharge of a starting light source at a lower starting voltage. .

  In order to solve the above problems, the present invention provides a discharge vessel of an arc tube with a pair of electrodes facing each other and at least a luminescent substance and a starting gas sealed therein, and the discharge vessel is filled with the arc tube. A pair of electrode sealing portions are formed by hermetically sealing the portions reaching both ends and sealing the electrodes, and are connected to the lighting circuit via electrode leads protruding from the end faces of the electrode sealing portions. A light source device comprising a high-pressure discharge lamp and a starting light source that irradiates the discharge vessel with ultraviolet light that enhances the starting performance at the time of starting lighting of the lamp. By a starting voltage applied between the electrodes, a discharge tube that generates ultraviolet rays by causing discharge between an internal electrode provided in the light emitting portion and an external electrode provided outside the discharge tube is formed. In the light emitting part, Serial Apart from internal electrodes, and wherein at least one of the charge concentration-forming metal piece is sealed.

  According to the present invention, when the high-pressure discharge lamp is turned on, for example, when the internal electrode is applied to the negative electrode and the external electrode is applied to the positive electrode, the internal voltage is applied between the internal electrode and the external electrode. When an electric field is formed and dielectric breakdown occurs between the internal electrode and the external electrode, ultraviolet rays are irradiated.

At this time, a metal piece is enclosed in the light emitting part, and if the metal piece is in contact with the internal electrode, it is applied to the negative electrode and the charge is concentrated on the edge part, and the edge part approaches the external electrode. , Dielectric breakdown is likely to occur at the edge, and discharge starts at a low voltage.
In addition, when the metal piece is not in contact with the internal electrode but is in contact with the inner peripheral surface of the light emitting portion, the light emitting portion is polarized and the inner peripheral surface has a polarity opposite to that of the internal electrode. Since it has an opposite polarity and charges are concentrated on the edge portion, and the edge portion approaches the internal electrode, dielectric breakdown tends to occur at the edge portion, and discharge starts at a low voltage.
In either case, the electric charge concentrates on the edge portion of the metal piece, and since it approaches the internal electrode or the external electrode, discharge tends to occur from the edge portion, and discharge starts at a low voltage.

1 is an overall view showing an example of a light source device according to the present invention. Explanatory drawing which shows an example of the discharge tube used as the light source for starting. The figure which shows the example of an enclosure metal piece. The schematic diagram which shows the ionization state in a discharge tube. The graph which shows the relationship between a starting voltage and the dielectric breakdown rate of a discharge tube. Explanatory drawing which shows the other Example of a light source device. The figure which shows the prior art for improving the starting performance of a high pressure discharge lamp.

  The light source device according to the present invention irradiates the discharge vessel with ultraviolet rays that enhance the starting performance when starting the lighting of the high-pressure discharge lamp in order to improve the startability by starting the discharge of the starting light source at a lower starting voltage. The starting light source includes an internal electrode provided in the light-emitting portion and an external electrode provided outside the discharge tube by a starting voltage applied between the electrodes when starting the lamp. The light emitting portion was sealed with at least one metal piece for forming a charge concentration portion separately from the internal electrode.

  A light source device S1 shown in FIG. 1 includes a high-pressure discharge lamp 1, a concave reflecting mirror 2 that reflects light emitted from the lamp 1, and a starting light source 3 that generates ultraviolet rays that enhance the starting performance of the lamp 1. ing.

  The high-pressure discharge lamp 1 has a pair of tungsten electrodes 6R, 6L facing each other with a short distance of about 1 mm in a discharge vessel 5 of an arc tube 4 made of quartz glass, and is made of mercury and bromine. A metal composed of each of the electrodes 6R and 6L and a molybdenum foil connected to each of the electrodes 6R and 6L is sealed by hermetically sealing a portion from the discharge vessel 5 to both ends of the arc tube 4 with a starting gas such as halogen and argon gas sealed therein. A pair of electrode sealing portions 9R and 9L are formed by sealing the foil 7 and the electrode lead 8 made of molybdenum wire.

  The electrode leads 8, 8 protruding from the end faces 10 of the electrode sealing portions 9R, 9L are connected to the one-pole side 12R and the other-pole side 12L of the lighting circuit 11 for supplying lamp power, respectively, and the electrode 6R. , A metal wire 13 serving as a trigger line / antenna wire for promoting arc discharge between 6L is connected to the electrode lead 8 projecting from the end face 10 of the electrode sealing portion 9R, and the other end side is an electrode sealing portion. It is wired so as to be wound around the outer periphery of 9L in a loop shape.

  The concave reflecting mirror 2 is formed with a bottom hole 14 at the bottom thereof through which one electrode sealing portion 9L of the high pressure discharge lamp 1 is inserted and fixed with cement or the like, and at the reflection portion, the high pressure discharge lamp 1 is formed. A wiring hole 16 through which a lead wire 15 made of a nickel wire connected to the electrode lead 8 protruding from the other electrode sealing portion 9R is inserted, and is pulled out from the wiring hole 16 to the back surface of the reflecting portion. A wiring fitting 17 for fixing the lead wire 15 is fixed.

  The starting light source 3 is connected in parallel with the lamp 1 to a lighting circuit 11 that applies a starting voltage between the electrodes 6R and 6L when the high-pressure discharge lamp 1 is started to light, and an internal electrode 19 of the discharge tube 18 When a starting voltage is applied between the external electrode 20 and the external electrode 20, ultraviolet rays are generated.

As shown in FIG. 2A, the main body of the discharge tube 18 is formed of a glass sealed tube 21 made of quartz glass, and the glass sealed tube 21 has a lead wire through a metal foil 28 on one end side. The internal electrode 19 made of a molybdenum metal rod 22 and the metal piece 29 for forming a charge concentration portion are accommodated and disposed, and the inside thereof is filled with a rare gas such as argon gas.
This glass sealed tube 21 is chipped off and sealed at one end side of the light emitting portion 23a filled with a rare gas, and the other end side is pinch-sealed to form a pinch seal portion 23b. A metal foil 28 such as a molybdenum foil welded to the internal electrode 19 and the lead wire 22 at both ends is sealed to the pinch seal portion 23b.
That is, the internal electrode 19 is extended so that the base end portion 19a is sealed to the pinch seal portion 23b of the discharge tube 18 and the tip end portion 19b is exposed from the pinch seal portion 23b into the light emitting portion 23a. .
Further, the internal electrode 19 is connected to the one pole side (electrode 6R side) 12R of the lighting circuit 11 via a lead wire 22 protruding from the pinch seal portion 23b of the glass sealed tube 21.

  The charge concentrating portion forming metal piece 29 is made of a refractory metal such as molybdenum, nickel, or tungsten, and its shape is arbitrary as long as it fits within the light emitting portion 23a. For example, as shown in FIG. The rectangular plate-like body is not limited to a rectangular plate-like body, but a rectangular plate-like body folded into a corrugated plate shape as shown in FIG. 3 (b), a rod-like one as shown in FIG. 3 (c), FIG. A pipe-shaped one as shown in FIG. 3), a coil-like one as shown in FIG. 3E, or a star-shaped one as shown in FIG. 3F can be used.

The external electrode 20 of the discharge tube 18 is provided close to or in close contact with both the light emitting portion 23a and the pinch seal portion 23b, and at least a portion provided in the light emitting portion 23a covers a part of the outer peripheral surface 24 of the discharge tube 18. It is formed by a holder H obtained by bending a metal plate into a shape that is held and held in an exposed state.
That is, in the holder H, a metal plate is bent so as to cover the outer peripheral surface 24 of the discharge tube 18, and the tip butting portion is formed in a separated shape, and the end surface 10 of the electrode sealing portion 9L A slit portion 20a that exposes a part of the outer peripheral surface 24 of the discharge tube 18 that faces is formed, and is formed in a shape that covers the outer peripheral surface 24 while leaving a portion exposed by the slit portion 20a.
Furthermore, the inner surface of the portion covering the outer peripheral surface of the discharge tube 18 is formed on the ultraviolet reflecting surface 20b, and by irradiating as much as possible the ultraviolet rays radiated from the discharge tube 18 toward the slit portion 20a, the irradiation of the ultraviolet rays is performed. The amount can be increased substantially.

  Further, the holder H is a terminal for fixing and electrically connecting the external electrode 20 to a conductor component (electrode lead 8) to which a voltage having a polarity opposite to that of the internal electrode 19 is applied by a part of the metal plate. A crimp tab terminal 26 is formed.

  In this example, the spring stainless steel having a thickness of 0.2 mm is provided so that the portions provided on the light emitting portion 23a and the pinch seal portion 23b grip and hold the outer peripheral surfaces of the light emitting portion 23a and the pinch seal portion 23b, respectively. It is formed by bending a single metal plate such as a steel plate (SUS304-CSP).

  2B, the terminal 26 of the holder H is bent so as to hold the electrode lead 8 and spot-welded to the electrode lead 8, so that the discharge tube 18 has a rigid molybdenum. At the same time as being securely fixed to the electrode lead 8 made of wire, the external electrode 20 made of a metal holder H is electrically connected to the other pole side (electrode 6L side) 12L of the lighting circuit 11. ing.

  Thereby, ultraviolet rays radiated from the outer peripheral surface 24 of the discharge tube 18 toward the end surface 10 of the electrode sealing portion 9L are directly incident on the end surface 10, and at the same time, from the outer peripheral surface 24 of the discharge tube 18 to the inner surface of the holder H2. Since the ultraviolet rays radiated toward the surface are also reflected by the inner surface and incident on the end surface 10 of the electrode sealing portion 9L, the starting performance of the lamp is remarkably improved.

The above is one configuration example of the present invention, and the operation thereof will be described next.
If the holder H is fixed to the electrode lead 8 with the slit 20a of the holder H facing up to the end face 10 of the electrode sealing portion 9L of the high-pressure discharge lamp 1, and the glass sealed tube 21 is inserted into this, the external The discharge tube 18 provided with the electrode 20 is attached. Then, if the lead wire 22 of the internal electrode 19 of the discharge tube 18 is connected to the unipolar side (electrode 6R side) 12R of the lighting circuit 11 by welding or the like, the mounting operation of the discharge tube 18 serving as the starting light source is completed.
At this time, since the holder H can be temporarily fixed to the electrode lead 8 by bending the tab terminal 26, the holder H can be positioned easily, and since it is electrically connected via the tab terminal 26, the troublesome external electrode 20 Wiring work can also be simplified.

  Here, when the high pressure discharge lamp 1 is turned on, a starting voltage is applied from the lighting circuit 11 between the internal electrode 19 and the external electrode 20 of the discharge tube 18, and the internal electrode 19 and the external electrode 20 have opposite polarities. When an electric field is formed between the two electrodes and dielectric breakdown occurs between the internal electrode and the external electrode, ultraviolet rays are irradiated.

In this example, since the charge concentration portion forming metal piece 29 is sealed in the light emitting portion 23a, for example, when the internal electrode 19 and the external electrode 20 are applied to the negative electrode and the positive electrode, respectively, as shown in FIG. Thus, if the metal piece 29 is in contact with the internal electrode 19, it has negative polarity.
At this time, the electric charge concentrates on the edge portion 30 of the metal piece 29, especially the corner portion 30a of the edge, and the distance from the edge portion 30 (30a) to the external electrode 20 becomes short, so the edge portion 30 (30a ), Dielectric breakdown tends to occur, and discharge starts at a low voltage.

Further, as shown in FIG. 4B, when the metal piece 29 is not in contact with the internal electrode 19 but is in contact with the inner peripheral surface of the light emitting portion 23a, the discharge is started at a low voltage.
That is, the light emitting portion 23 a is polarized by the electric field formed between the internal electrode 19 and the external electrode 20, and its inner peripheral surface is applied to the positive electrode having the opposite polarity to the internal electrode 19. The metal piece 29 is also opposite in polarity to the internal electrode 19, and electric charges are concentrated on the edge portion 30 (30a), and since the edge portion approaches the internal electrode, dielectric breakdown tends to occur at the edge portion, Discharge starts at low voltage.

  As described above, in both cases, whether or not the metal piece 29 is in contact with the internal electrode 19, charges are concentrated on the edge portion 30 (30 a) of the metal piece 29, and the metal piece 29 approaches the internal electrode 19. Therefore, discharge is likely to occur from the edge portion 30 (30a), and therefore, discharge is started at a low voltage.

  Then, dielectric breakdown occurs between the internal electrode 19 and the external electrode 20, and a discharge that excites the rare gas in the rare gas sealed in the glass sealed tube 21 that forms the main body of the discharge tube 18 occurs to generate ultraviolet rays. The generated ultraviolet rays are emitted from the slit 20a of the holder H that forms the external electrode 20, and are incident on the end surface 10 of the electrode sealing portion 9L of the lamp 1, and are transmitted through and propagated through the electrode sealing portion 9L to discharge. By irradiating the inside of the vessel 5, the starting gas sealed in the discharge vessel 5 is excited, and tungsten forming the electrodes 6 </ b> R and 6 </ b> L emits initial electrons necessary for starting the discharge, and the high-pressure discharge lamp 1. The start of is promoted.

In this example, the external electrode 20 of the discharge tube 18 is provided in close proximity or close to both the light emitting portion 23a and the pinch seal portion 23b, and at least a portion provided in the light emitting portion 23a grips the outer peripheral surface 24. Since it is formed with a holder H made of a metal plate bent into a shape to be held, the electrode area is smaller than when it is provided only in the light emitting part or when it is formed by winding a coil. It is much larger and can generate a sufficient amount of ultraviolet rays to enhance the starting performance of the lamp.
Further, the slit portion 20a of the holder H is opposed to the end surface 10 of the electrode sealing portion 9L, and the inner surface side of the portion covering the outer peripheral surface 24 of the discharge tube 18 is formed by the ultraviolet reflecting surface 20b. Ultraviolet rays generated in the discharge tube 18 can be radiated from the slit portion 20a without waste and efficiently incident on the end face 10 of the electrode sealing portion 9L.
Furthermore, if it is provided at a position facing the end face 10 of the electrode sealing portion 9L of the high-pressure discharge lamp 1, it will not be heated to a high temperature while the lamp is turned on. Discharge can be generated to generate ultraviolet rays.

  Further, since the discharge tube 18 has a simple configuration, its production cost is not increased. Further, since the holder H that holds the outer peripheral surface 24 of the discharge tube 18 is fixed by welding to the electrode lead 8 of the lamp 1, there is no fear of dropping from the electrode lead 8, and the electrode lead 8 has rigidity. Since the electrode lead 8 is bent unexpectedly, the outer peripheral surface 24 of the discharge tube 18 held by the holder H does not face the end surface 10 of the electrode sealing portion 9L. There is no risk of it occurring.

FIG. 5 is a graph showing the relationship between the starting voltage and the dielectric breakdown rate of the discharge tube. The experimental data D ₁ of the discharge tube 18 enclosing the metal piece 29 for forming the charge concentration portion shown in FIG. condition shown by comparing the experimental data D ₂ differ only discharge tube in that it does not enclose the charge concentration-forming metal piece 29 in the same.
From this graph, when the starting voltage is 1 kV, the discharge tube not encapsulating the metal piece 29 has a very low dielectric breakdown probability of about 10%, and almost no dielectric breakdown, whereas the metal piece 29 is encapsulated. The discharge tube 18 had a dielectric breakdown probability of 100%, and dielectric breakdown was observed in all of them.
That is, even if the starting voltage is reduced to 1 kV, the discharge tube 18 is dielectrically broken and ultraviolet rays are reliably generated, so that the starting of the high-pressure discharge lamp 1 is promoted.

  FIG. 6 shows another embodiment. 1 and 2 are denoted by the same reference numerals, and detailed description thereof is omitted.

In the light source device S2 of this example, a ceramic metal halide lamp in which a ceramic heat-resistant luminous tube 33 is housed in a glass hermetic tube 32 is used as the high-pressure discharge lamp 31, and a starting light source is provided inside the hermetic tube 32. A discharge tube 18 is arranged.
The airtight tube 32 is hot-pressed at one end side to form a pinch seal portion 34, and a pair of lead wires 36A and 36B connected to electrode leads 35A and 35B led out from both ends of the arc tube 33 are the pinch seal. It is led out of the airtight tube 32 from the portion 34.

  The ceramic arc tube 33 is provided with a pair of electrodes (not shown) facing each other in the discharge vessel 37, and at least a luminescent substance and a starting gas are enclosed between the discharge vessel 37 and both ends of the arc tube 32. A pair of electrode sealing portions 38A and 38B are formed by hermetically sealing the portions extending to the ends and sealing the electrodes, and the electrode leads 35A and 35B protruding from the end surfaces of the electrode sealing portions are lead wires. It is connected to a lighting circuit (not shown) through 36A and 36B.

  Since the light-emitting portion 23a of the discharge tube 18 is filled with a metal piece 29 for forming a charge concentration portion having an arbitrary shape, when the metal piece 27 is in contact with the internal electrode 19, it is charged with the same polarity. When the light emitting portion 23a is in contact with the inner peripheral surface without being in contact with the internal electrode 19, it is charged with the opposite polarity of the internal electrode 19, and in either case, the edge portion 30 (particularly the corner portion 30a) is charged. In addition, since the distance between the electrodes is substantially shortened, dielectric breakdown is likely to occur between the internal electrode 19 and the external electrode 20.

The holder H that becomes the external electrode 20 of the discharge tube 18 is bent so that the slit portion 20a faces the arc tube 33 and the tab terminal 26 grips the lead wire 36B that feeds the other electrode lead 35B of the arc tube 33. In addition to being crimped, it is spot welded and fixed.
The lead wire 22 of the internal electrode 19 is welded to a lead wire 36 </ b> A that supplies power to one electrode lead 35 </ b> A of the arc tube 33.

Also in this example, by using the tab terminal 26, the holder H can be easily fixed, the wiring work to the external electrode 20 can be simplified, and the internal electrode 19 of the discharge tube 18 attached to the holder H can be connected to the lead wire 36A. It is possible to easily attach the discharge tube 18 serving as a starting light source.
When the high pressure discharge lamp 31 is turned on, a starting voltage is applied between the internal electrode 19 and the external electrode 20 of the discharge tube 18 via the lead wires 36A and 36B, and the internal electrode 19 and the external electrode 20 are applied. Have opposite polarities and an electric field is formed between them.
At this time, charges concentrate on the edge portion 29 of the charge concentration portion forming metal piece 29 enclosed in the light emitting portion 23a, and the presence of the metal piece 29 substantially reduces the distance between the electrodes. Destruction tends to occur, and discharge is started at a low voltage, and ultraviolet rays are irradiated.

  When ultraviolet rays are irradiated from the discharge tube 18, the ultraviolet rays are emitted from the slits 20 a of the holder H and irradiated to the arc tube 33, thereby exciting the starting gas sealed in the arc tube 33. Tungsten forming an electrode (not shown) emits initial electrons necessary to start discharge, and the start-up of the high-pressure discharge lamp 31 is promoted.

Also in this example, the external electrode 20 of the discharge tube 18 is provided in close proximity or close to both the light emitting part 23a and the pinch seal part 23b, so that the electrode area is remarkably large and the starting performance of the lamp is enhanced. It is possible to generate a necessary and sufficient amount of ultraviolet rays.
Further, since the inner surface side of the portion of the holder H that covers the outer peripheral surface 24 of the discharge tube 18 is formed by an ultraviolet reflecting surface, the ultraviolet rays generated in the discharge tube 18 are radiated from the slit portion 20a without waste, and the discharge vessel 37 Can be efficiently incident on the inside.

In the description of the above embodiment, the outer electrode 20 is provided so that the portions provided on the light emitting portion 23a and the pinch seal portion 23b grip and hold the outer peripheral surfaces of the light emitting portion 23a and the pinch seal portion 23b, respectively. However, the present invention is not limited to this, and it is sufficient that at least the portion provided in the light emitting portion 23a is formed by bending the metal plate, and the pinch is used. The portion provided in the seal portion 23b may be formed by, for example, winding a coil having one end connected to the holder H around the pinch seal portion 23b.
Moreover, not only the case where the slit part 20a is formed in the holder H but the case where a through-hole is formed may be sufficient.
Furthermore, the internal electrode 19 of the discharge tube 18 is not limited to the rod-shaped one, and may be a case where the metal foil 28 is directly extended in the light emitting portion 23a.

  The present invention contributes to an improvement in starting performance of a high-pressure discharge lamp used in a light source device such as a liquid crystal projector, a DLP projector, or an illumination device.

S1 Light source device 1 High pressure discharge lamp
3 Light source for starting
18 Discharge tube
19 Internal electrode
20 External electrode
23a Light emitting part 23b Pinch seal part 24 Outer peripheral surface
H holder
26 terminals
29 Metal piece for forming charge concentration part

Claims (5)

In the discharge vessel of the arc tube, a pair of electrodes are arranged opposite to each other, and at least a luminescent material and a starting gas are enclosed, and a portion extending from the discharge vessel to both ends of the arc tube is hermetically sealed. A pair of electrode sealing portions each sealing each electrode is formed, and a high-pressure discharge lamp connected to the lighting circuit via an electrode lead protruding from the end face of each electrode sealing portion; In a light source device comprising a starting light source that irradiates the discharge vessel with ultraviolet light that enhances starting performance,
The starting light source causes a discharge between an internal electrode provided in the light emitting portion and an external electrode provided outside the discharge tube by a starting voltage applied between the electrodes when the lamp is turned on. Formed by a discharge tube that generates ultraviolet rays,
A light source device, wherein at least one metal portion for forming a charge concentration portion is enclosed in the light emitting portion separately from the internal electrode.   The light source device according to claim 1, wherein the external electrode is formed of a holder that holds and holds the discharge tube.   The light source device according to claim 2, wherein the holder is formed by bending a metal plate into a shape that holds and holds the outer peripheral surfaces of both the pinch seal portion that seals the internal electrode and the light emitting portion.   The high-pressure discharge lamp is a metal halide lamp in which a heat-resistant arc tube is housed in an airtight outer sphere, and the starting light source is disposed in the outer tube, and electrode leads projecting from both ends of the arc tube The light source device according to claim 2 or 3, wherein an internal electrode is connected to one side and an external electrode is fixed to the other side via a terminal of the holder. The electrode sealing portion on one side of the high-pressure discharge lamp is attached by being inserted into a bottom hole opened at the bottom of the concave reflecting mirror, and the outer peripheral surface from which the discharge tube of the starting light source is exposed by the holder The light source device according to claim 2, wherein an external electrode is fixed to the electrode lead that is held so as to face the end face of the electrode sealing portion and protrudes from the end face via the terminal.

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