Discharge lamp

Abstract

The invention provides a discharge lamp which is difficult to reduce in startability even at the end of service life and has a longer service life than the prior art. The discharge lamp is provided with: a pair of electrodes arranged facing each other in one axial direction; a bulb having a light-emitting tube portion having the pair of electrodes therein, and two side tube portions respectively connected from both ends of the light-emitting tube portion positioned in the one axial direction; two lead rods respectively supporting the pair of electrodes; a non-conductive support member which is located in at least one of the two side tube portions and supports the lead rod; a conductive member which is located in the side tube portion having the support member therein and is in contact with the lead bar; and a trigger member provided outside the bulb and disposed on the outer periphery of the conductive member.

Description

Technical Field

[0001] This invention relates to discharge lamps. Background Technology

[0002] Ultra-high pressure mercury lamps have long been known as light sources used in exposure apparatuses for manufacturing semiconductors, display devices, or wiring boards. An ultra-high pressure mercury lamp has an anode and cathode arranged opposite each other within its light-emitting tube section, and is sealed with mercury as a luminescent gas. The anode and cathode are each supported by lead rods, and each lead rod is supported by a pair of side tubes connected to both ends of the light-emitting tube section. When a voltage is applied between the electrodes, an electric arc discharge is generated in the mercury vapor within the light-emitting tube, causing the ultra-high pressure mercury lamp to emit light.

[0003] One of the performance indicators of discharge lamps such as ultra-high pressure mercury lamps is their starting performance. Starting performance refers to the time from when power is supplied to the discharge lamp until it actually lights up. Good starting performance indicates a short time from when power is supplied to the discharge lamp until it actually lights up. In this specification, the starting performance of the discharge lamp will be simply referred to as "starting performance".

[0004] As one method to improve startability, the use of a trigger member is known. Patent Document 1 discloses a metal halide lamp (a type of discharge lamp) in which a trigger member is wound around a side tube. When the lamp is started (lighting begins), an electric current is applied to the trigger member, generating a dielectric barrier discharge inside the bulb, thereby making the discharge lamp easier to light. That is, a scheme for configuring a trigger member to improve startability is known.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: Japanese Patent Application Publication No. 9-97591 Summary of the Invention

[0008] The problem that the invention aims to solve

[0009] As the cumulative lighting time of the discharge lamp increases, its lifespan approaches, and its startability deteriorates. When startability deteriorates, sometimes there will be a delay before the discharge lamp lights up, or the lamp may not light up at all. When the time until the discharge lamp lights up exceeds the allowable time, or when the discharge lamp does not light up, it is determined that the discharge lamp has reached the end of its lifespan.

[0010] From a market perspective, there is a demand for longer lifespan discharge lamps. The purpose of this invention is to provide a discharge lamp whose startability is not easily reduced even at the end of its lifespan and whose lifespan is longer than before.

[0011] Technical solutions for solving the problem

[0012] The discharge lamp of the present invention has: a pair of electrodes arranged opposite to each other in one axial direction;

[0013] The light bulb has a light-emitting tube portion having the pair of electrodes inside, and two side tube portions respectively connected to the two ends of the light-emitting tube portion located in one axial direction;

[0014] Two lead rods support the pair of electrodes respectively;

[0015] A non-conductive support member is located inside at least one of the two side tubes and supports the lead bar.

[0016] A conductive member, located within the side tube portion having the supporting member, and in contact with the lead bar; and

[0017] A trigger component is disposed outside the light bulb and on the outer periphery of the conductive component.

[0018] Without a conductive member, dielectric barrier discharge needs to be generated in a large gap between the lead bar and the trigger member. However, the discharge lamp has the conductive member, and a trigger member is located on the outer periphery of the conductive member. Because the trigger member is located on the outer periphery of the conductive member, dielectric barrier discharge can be generated in a small gap between the conductive member and the trigger member. In this specification, "trigger member located on the outer periphery of the conductive member" means that the trigger member is located at a position that can provide starting power to the conductive member through dielectric barrier discharge. Moreover, dielectric barrier discharge promotes the discharge of accompanying light emission between a pair of electrodes (anode and cathode). Therefore, insulation breakdown performance is improved, and the probability of the discharge lamp lighting up is increased.

[0019] Alternatively, the conductive component can be a thin sheet. For example, the thickness of the conductive component in one axial direction can be less than 0.4 mm. Alternatively, the thickness of the conductive component in one axial direction can be less than 0.1 mm. If the thickness of the conductive component is reduced, the electric field strength of the dielectric barrier discharge increases, which makes it easier for a discharge accompanied by luminescence to occur between a pair of electrodes.

[0020] Alternatively, the discharge lamp may include a fixing member for fixing the conductive component.

[0021] The conductive member is clamped between the support member and the fixing member. This suppresses positional displacement of the conductive member, ensuring stable use of the discharge lamp.

[0022] Alternatively, the fixing member may be supported on the lead bar, and the fixing member may be made of a conductive material that electrically connects the lead bar and the conductive member. A fixing member made of conductive material can reliably maintain conductivity between the conductive member and the lead bar.

[0023] Alternatively, a conductive film may be provided between the conductive member and the trigger member on the outer surface of the bulb. Details will be described later, but the conductive film functions as a heat-insulating film for heating or maintaining the temperature of the fluid (e.g., mercury) filled in the discharge lamp. Furthermore, when the conductive film is located between the conductive member and the trigger member, the conductive film facilitates dielectric barrier discharge.

[0024] Alternatively, the distance between the conductive component and the trigger component can be less than 25 mm. This increases the probability of insulation failure between the anode and cathode, promoting discharge between the two electrodes.

[0025] Alternatively, the distance between the front end of the electrode supported by the lead bar, which is in contact with the conductive member, and the conductive member is less than 220 mm. When the conductive member approaches the front end of the electrode, the part that generates dielectric barrier discharge is close to the part that generates discharge between the pair of electrodes, thus improving the insulation breakdown performance and promoting discharge between the pair of electrodes.

[0026] Alternatively, the conductive member may have a protrusion projecting radially outward in a cross-section orthogonal to the stated axial direction. This protrusion enhances the electric field strength of the dielectric barrier discharge. Consequently, it facilitates the generation of a discharge accompanied by luminescence between the pair of electrodes.

[0027] Invention Effects

[0028] This enables the production of discharge lamps with longer lifespans and less reduced startability even at the end of their lifespan. Attached Figure Description

[0029] Figure 1 This is a diagram illustrating one embodiment of a discharge lamp.

[0030] Figure 2 yes Figure 1 Enlarged view of the main parts.

[0031] Figure 3 This is a diagram illustrating the comparison method of discharge lamps.

[0032] Figure 4 This is a diagram representing a conductive component.

[0033] Figure 5 This is a diagram showing a modified example of a conductive component.

[0034] Figure 6 This is an enlarged view of the main part of a modified discharge lamp.

[0035] Figure 7A This is a diagram illustrating the experimental setup S1 for the discharge lamp.

[0036] Figure 7B This is a diagram illustrating the test setup S2 for the discharge lamp.

[0037] Figure 7C This is a diagram illustrating the test setup S3 for the discharge lamp.

[0038] Figure 7D This is a diagram illustrating the test setup S4 for the discharge lamp.

[0039] Figure 8 This is an enlarged view of the main parts of the discharge lamp. Detailed Implementation

[0040] Hereinafter, an embodiment and variations thereof of the discharge lamp described above will be described with reference to the accompanying drawings. Furthermore, the drawings disclosed in this specification are merely schematic illustrations. That is, the aspect ratios in the drawings may not correspond to the actual aspect ratios, and the aspect ratios may not be consistent between different drawings.

[0041] The following explanation will refer to the XYZ coordinate system as appropriate. Furthermore, in this specification, when indicating direction, positive and negative directions are distinguished, such as "+X direction" and "-X direction" using positive and negative symbols. Conversely, when indicating direction without distinguishing positive and negative directions, it will only be described as "X direction". That is, in this specification, when only "X direction" is described, it includes both "+X direction" and "-X direction". This also applies to the Y and Z directions. The -Z direction indicates vertically downwards (the direction of gravity).

[0042] [Overall structure of the lamp]

[0043] Figure 1This refers to a short-arc type ultra-high pressure mercury lamp 100 (hereinafter referred to as "lamp 100") as one embodiment of the discharge lamp of the present invention. The lamp 100 includes: a light-emitting tube section 1; a first side tube section 2a connected to one end of the light-emitting tube section 1 in the tube axis direction (Z direction); a second side tube section 2b connected to the other end of the light-emitting tube section 1 in the tube axis direction; an anode 3 and a cathode 4 arranged opposite each other along the Z direction inside the light-emitting tube section 1; and lead rods 6 connected to the anode 3 or the cathode 4; and a lamp holder 12 electrically connected to each lead rod 6. The light-emitting tube section 1, the first side tube section 2a, and the second side tube section 2b constitute a bulb 5 forming a sealed space. The bulb 5 (light-emitting tube section 1, first side tube section 2a, and second side tube section 2b) is made of quartz. In the discharge lamp of this embodiment, the lamp 100 is arranged such that the anode 3 is above the cathode 4 when the lamp 100 is lit.

[0044] The lead rod 6, connected to the anode 3, is supported within the first side tube 2a by a non-conductive support member 7. The support member 7 is fixed by being at least partially internally connected to the first side tube 2a. In this embodiment, the support member 7 is cylindrical with a central through hole. The lead rod 6 is inserted through the through hole. The bulb 5, anode 3, cathode 4, lead rod 6, and support member 7 are all rotationally symmetrical about the Z1 axis. The shapes of the bulb 5, anode 3, cathode 4, and support member 7 are not limited to those shown in this embodiment and can be other shapes. The anode 3, cathode 4, and lead rod 6 are made of a material containing a high-melting-point metal, such as tungsten.

[0045] In this embodiment, the support member 7 is made of quartz, for example. As described above, the first side tube 2a is made of quartz. When the support member 7 and the first side tube 2a are made of the same material, the coefficient of thermal expansion of the support member 7 is the same as that of the first side tube 2a. Therefore, it is preferable that thermal strain associated with temperature changes in the lamp 100 is less likely to occur between the support member 7 and the first side tube 2a. Similarly, the support member 7 in the second side tube 2b, which supports the lead rod 6 connected to the cathode 4, is also made of quartz. However, the material of the support member 7 may be different from that of the side tubes (2a, 2b).

[0046] Two lamp holders 12 are electrically connected to an igniter 15 via a power supply line 13. The igniter 15 is electrically connected to a power supply 16 of the lamp 100. Upon startup (when the lamp 100 begins to illuminate), the igniter 15 applies a starting pulse voltage to a pair of electrodes (3, 4). However, in this specification, the power supply line 13, the igniter 15, and the power supply 16 are not considered components of the lamp 100.

[0047] Mercury is sealed inside the bulb 5. When a voltage is applied between the cathode 4 and the anode 3, the mercury is heated, and the sealed space is filled with mercury vapor. An electric arc discharge is generated in the mercury vapor at the cathode 4 and the anode 3, and the lamp 100 emits light. As described above, the lamp 100 of this embodiment is a short-arc type ultra-high pressure mercury lamp. In this specification, "short-arc type" refers to a lamp in which the anode 3 and the cathode 4 are arranged opposite each other with a gap of 35 mm or less (at room temperature without thermal expansion). In this specification, "ultra-high pressure" means that when the lamp 100 is lit, the light-emitting tube is at a pressure of 5 × 10⁻⁶ mm. 5 Pa~2×10 7 Pa of pressure.

[0048] The lamp 100 has a trigger member 10 outside the bulb 5. The trigger member 10 is disposed outside the bulb 5 and on the outer periphery of the conductive member 8. In this embodiment, the trigger member 10 is a flexible, wire-like component called a "trigger wire". The trigger member 10 is wound around the tubes of the first side tube portion 2a and the second side tube portion 2b in a loop-like manner. In this embodiment, the loop-shaped trigger member 10 is located on the outer periphery of the conductive member 8. The trigger member 10 around the first side tube portion 2a and the trigger member 10 around the second side tube portion 2b are connected to each other by wires. For example, when a dielectric barrier discharge occurs between one of the trigger members 10 and the conductive member 8 near that trigger member 10, the trigger member 10 of that trigger member is applied and conducted on the wire, and a dielectric barrier discharge occurs between the other trigger member 10 and the conductive member 8 near that other trigger member 10. Thus, the trigger member 10 functions as an auxiliary wire for generating a dielectric barrier discharge within the lamp 100 and promoting arc discharge between the anode 3 and the cathode 4.

[0049] Thus, the trigger member 10 and the igniter 15 are not physically connected by wires, but are electrically connected to the lead bar 6 of either one via a dielectric barrier discharge passing through the conductive member 8. As a result, the trigger member 10 is activated. The igniter 15 in this embodiment is DC type, supplying DC power to the trigger member 10. The trigger member 10 functions as an auxiliary line for generating a dielectric barrier discharge within the lamp 100 and promoting an arc discharge between the anode 3 and the cathode 4. The igniter 15 applies a starting pulse voltage to the trigger member 10 upon startup (when the lamp 100 begins to light up). As a result, a dielectric barrier discharge is generated from the bulb 5 near the trigger member 10. The dielectric barrier discharge breaks the insulation between a pair of electrodes (3, 4) within the bulb, promoting an arc discharge between the pair of electrodes (3, 4). This facilitates the startup (lighting up) of the lamp 100.

[0050] To facilitate lamp activation, it is preferable that the trigger member 10 is formed in a loop along the same XY plane as the conductive member 8. However, the components that function as the trigger member 10 are not limited to wires forming a loop along the same XY plane as the conductive member 8. The trigger member 10 could, for example, be a wire positioned slightly offset in the Z direction from the same XY plane as the conductive member 8. The trigger member 10 only needs to be positioned on the outer periphery of the conductive member 8, where it can provide starting power to the conductive member 8 through dielectric barrier discharge. Furthermore, as described later... Figure 7B As in the structure described above, even if the annular trigger member 10 itself is wound away from the conductive member 8 in the axial direction, if a portion 10w of the wire connected to the trigger member 10 is located on the outer periphery of the conductive member 8, then that portion 10w also functions as the trigger member 10. The trigger member 10 may not be linear; for example, it may be strip-shaped or rod-shaped.

[0051] The lamp 100 has a heat-insulating film 9 on the outer surface of the bulb 5. The heat-insulating film 9 is a film provided to promote the evaporation of mercury sealed inside the bulb 5. In this embodiment, it is formed in the area on the first side tube 2a and in the area from a portion of the light-emitting tube 1 near the second side tube 2b to the second side tube 2b. In this embodiment, the heat-insulating film 9 is a metal film called "mercury-metal" and has electrical conductivity. Details of the heat-insulating film 9 will be described later.

[0052] The lamp 100 has conductive members 8 inside the first side tube portion 2a and the second side tube portion 2b, respectively. The conductive members 8 are in contact with the lead rod 6. In this embodiment, the conductive members 8 are arranged to contact the end face of the light-emitting tube portion 1 of the support member 7. The effect of the conductive members 8 will be explained.

[0053] [Functions and details of conductive components]

[0054] Compare Figure 2 and Figure 3 The effect of the conductive component 8 on the lamp 100 is explained. Figure 2 yes Figure 1 An enlarged view of region C1. Region C1 shows the cathode 4, a portion of the lead rod 6 connected to the cathode 4, the support member 7 supporting the lead rod 6, the conductive member 8, and a portion of the bulb 5 extending from a portion of the light-emitting tube section 1 to a portion of the second side tube section 2b. Figure 3 The region corresponding to region C1 is shown for the discharge lamp used as a comparison. The discharge lamp used as a comparison does not have conductive component 8.

[0055] exist Figure 2In this configuration, the distance between the conductive member 8 and the trigger member 10 is d1. If a pulse voltage is applied to the trigger member 10, a dielectric barrier discharge is generated at the distance d1. Conversely, Figure 3 The discharge lamp shown in the comparison configuration does not have a conductive member 8. Therefore, in this discharge lamp, dielectric barrier discharge is generated at the interval d3 between the lead bar 6 and the trigger member 10. In other words, due to the presence of the conductive member 8, the interval d1 is narrower than the interval d3. This makes it easier for dielectric barrier discharge to occur. If dielectric barrier discharge becomes easier to generate, insulation breakdown is more likely to occur between the pair of electrodes (3, 4), resulting in easier initiation of arc discharge. Thus, by arranging the conductive member 8, dielectric barrier discharge is easily generated, thereby improving insulation breakdown performance. As a result, even at the end of the lamp 100's lifespan when its startability decreases, startability is easily maintained, and the lifespan of the lamp 100 is extended.

[0056] When the insulation film 9 is a conductive film (e.g., a metal film), by bringing the trigger member 10 into contact with the insulation film 9, the insulation film 9 can become an electrode for dielectric barrier discharge. In this case, the interval for generating dielectric barrier discharge is d2. The interval d2 is narrower than the interval d1. Therefore, dielectric barrier discharge is more likely to occur, further improving the insulation performance.

[0057] Figure 4 This diagram only shows the conductive member 8. The conductive member 8 in this embodiment is generally circular, with a through hole 8h centered on the Z1 axis. The thickness t1 of the conductive member 8 in the Z-axis direction is thin. The conductive member 8 can also be sheet-like. The thickness t1 can be, for example, less than 0.4 mm or less, or less than 0.1 mm. The thinner the thickness t1, the higher the electric field strength of the dielectric barrier discharge.

[0058] The inner diameter a1 of the through hole 8h of the conductive member 8 can be the same as or slightly smaller than the outer diameter of the lead rod 6. This ensures reliable contact between the conductive member 8 and the lead rod 6.

[0059] The outer diameter a2 of the conductive member 8 can be smaller than the inner diameter of the second side tube 2. For example... Figure 2 As shown, a gap is ensured between the conductive member 8 and the second side tube 2b (bulb 5). Therefore, even when the lamp 100 is lit, the conductive member 8 will not come into contact with the inner wall of the second side tube 2b. The coefficient of thermal expansion of the conductive member 8 is different from that of the second side tube 2b; therefore, when the thermally expanded conductive member 8 comes into contact with the inner wall of the second side tube 2b, either the conductive member 8 or the second side tube 2b may deform. However, when the conductive member 8 does not come into contact with the inner wall of the second side tube 2b, neither the conductive member 8 nor the second side tube 2b will deform due to contact with each other.

[0060] The conductive component 8 is made of a conductive metallic material. The conductive component 8 can be made of a high-melting-point material that does not melt even when the lamp is lit at 100°C. For example, the conductive component 8 can also be a molybdenum-based material or a tungsten-based material.

[0061] like Figure 1 As shown, a conductive member 8 can also be arranged between the anode 3 and the support member 7 of the lead bar 6 supporting the anode 3, and the interval with the trigger member 10 can be narrowed.

[0062] The shape of the conductive component 8 is not particularly limited. Figure 5 This shows a variation of the conductive component 8. Figure 5 The conductive member 28 shown is generally circular with an outer diameter 8c, but has multiple protrusions 8p projecting radially from the outer diameter 8c. The protrusions 8p enhance the electric field strength for dielectric barrier discharge. Figure 5 In the diagram, when viewed along the Z1 axis, the four protrusions 8p are spaced at a certain angle (90 degrees). Therefore, dielectric barrier discharge can easily occur from any direction.

[0063] [Fixed Components]

[0064] The conductive component 8 is fixed by the fixing component 11. For example... Figure 2 As shown, in this embodiment, the fixing member 11 is in the form of a coil wound around the lead bar 6. One end of the coil-shaped fixing member 11 is fixed to the lead bar 6. Thus, the fixing member 11 is supported by the lead bar 6. The other end of the fixing member 11 presses the conductive member 8 against the end face of the support member 7 near the cathode 4. The conductive member 8 is held by the fixing member 11 and the support member 7. More preferably, the fixing member 11 is made of a conductive component. In this way, the fixing member 11 functions as a conductive path between the lead bar 6 and the conductive member 8.

[0065] [Insulating film]

[0066] The details of the insulating film 9 will be explained. The insulating film 9 is located between the conductive member 8 and the trigger member 10. As described above, in this embodiment, the lamp 100 is arranged such that the anode 3 is above the cathode 4. Therefore, unevaporated liquid mercury accumulates on the support member 7 that supports the lead bar 6 connected to the cathode 4. The insulating film 9 reflects a portion of the light generated by the lamp 100 toward the mercury accumulated on the support member 7, and the reflected light heats the mercury. This promotes the evaporation of mercury, increases arc discharge, and increases the amount of light emitted.

[0067] Thus, the insulating film 9 is a film designed to promote mercury evaporation. However, when the insulating film 9 is a conductive material, as described above, it can also function as an electrode for generating dielectric barrier discharge. However, the insulating film 9 can also be a non-conductive film or a film other than metal. The trigger member 10 may not be electrically connected to the insulating film 9.

[0068] Figure 6 This is an enlarged view of the main part of a modified example of lamp 100. This discharge lamp does not have the insulating film 9. Even without the insulating film 9, the discharge lamp still functions to generate dielectric barrier discharge by providing the trigger member 10. Therefore, the insulating film 9 is an additional constituent element of this invention.

[0069] The above describes the embodiments and variations of lamp 100. This invention is not limited to the embodiments described above; various changes or improvements can be made to the embodiments without departing from the spirit of the invention. Furthermore, although in Figure 1 Although not shown in the diagram, the bulb 5 of lamp 100 may also have a sealing portion that serves as a trace of the exhaust pipe installed in the lamp during manufacturing. The sealing portion may, for example, be shaped such that the exhaust pipe, which is sealed internally, protrudes outward from the light-emitting tube portion 1.

[0070] The discharge lamps using this invention are not limited to the short-arc type ultra-high pressure mercury lamps described above. For example, they can be long-arc type ultra-high pressure mercury lamps, metal halide lamps that emit light based on metal vapors that are not mercury, or flash lamps (e.g., xenon flash lamps).

[0071] [First Experiment]

[0072] To confirm the effects of different discharge lamps based on the presence or absence of conductive member 8 and the different configuration methods of conductive member 8, the following experiment (first experiment) was conducted. The first experiment was conducted using an experimental apparatus equipped with a discharge device 200 that simulates lamp 100. Figures 7A to 7D This indicates the various experimental setups. For example... Figures 7A to 7D As shown, the entire experimental setup includes a discharge device 200, an igniter 15 with variable output (a DC igniter), and a power supply 16. The discharge device 200... Figures 7A to 7D Similar to the one used in lamp 100, it has an anode 3 with a shape similar to the anode 3 used in lamp 100, a lead bar 6 connected to the anode 3, a cathode 4 made by sharpening the front end of the lead bar 6, a cylindrical bulb 5 with a constant diameter, a non-conductive support member 7, and a linear trigger member 10. Argon gas is sealed inside the cylindrical bulb 5.

[0073] Experimental apparatus S1 is Figure 7AThe discharge device 200 is shown. In the test apparatus S1, the conductive member 8 is fixed to the anode side end face of the support member 7. The trigger member 10 is arranged to overlap with the conductive member 8 in the tube axis direction of the discharge device 200.

[0074] Experimental apparatus S2 is Figure 7B The discharge device 210 is shown. In the test apparatus S2, the conductive member 8 is fixed to the anode side end face of the support member 7. The trigger member 10 is not arranged to overlap with the conductive member 8 in the tube axis direction of the discharge device 210, and the trigger member 10 is arranged at a position farther away from the two electrodes (3, 4) than the conductive member 8.

[0075] Test apparatus S3 is Figure 7C The discharge device 220 is shown. In the test apparatus S3, the conductive member 8 is fixed between two support members (7a, 7b). The support members 7a and 7b have the same thickness in the axial direction of the discharge device 220. The trigger member 10 is arranged to overlap with the conductive member 8 in the axial direction of the discharge device 220. The position of the trigger member 10 in the axial direction of the discharge device 220 in the test apparatus S3 is the same as the position of the trigger member 10 in the axial direction of the discharge device 220 in the test apparatus S2.

[0076] Test apparatus S4 is Figure 7D The discharge device 230 shown. The discharge device 230 does not have a conductive member 8. The position of the trigger member 10 of the test device S4 in the tube axis direction of the discharge device 230 is the same as the position of the trigger member 10 in the test device S1 in the tube axis direction of the discharge device 200.

[0077] The following experiments were conducted on each test setup S1~S4: while changing the output voltage of igniter 15, the probability of insulation failure of the discharge devices (200, 210, 220, 230) in each test setup was investigated. Insulation failure refers to the breakdown of the insulation between the electrodes of the discharge device, which initiates discharge; in the case of a discharge lamp, the breakdown of the insulation between the electrodes of the discharge device initiates discharge and ignites. A low output voltage of igniter 15 and a high probability of insulation failure indicate excellent start-up performance of the discharge device (discharge lamp). Table 1 shows the experimental results.

[0078] [Table 1]

[0079]

[0080] In Table 1, 9kV, 12kV, 16kV, 19kV, and 26kV represent the output voltage of igniter 15. Regarding the probability of insulation failure, the denominator "10" indicates the number of times power is supplied from igniter 15 (10 times). The values ​​in the numerator represent the number of times insulation failure occurred (i.e., the number of times the discharge lamp lit) out of 10 power supplies. For example, in test setup S1, with the output voltage of igniter 15 at 9kV, this means that insulation failure occurred 7 out of 10 times, and discharge began, but insulation failure did not occur 3 out of 10 times, and discharge did not begin. However, in test setup S1, if the output voltage of igniter 15 is set to 12kV, then insulation failure occurred 10 out of 10 times, and discharge began.

[0081] As described above, the lower the output voltage of the igniter 15 that can cause insulation failure, the better the lamp's startability. Based on the obtained insulation failure probability of the igniter 15 according to its output voltage, the startability of test devices S1 to S4 is evaluated in three stages, S, A, and B, from best to worst. Test device S1 is rated as S (highest). Test devices S2 and S3 are rated as A (second highest). Test device S4 is rated as B (lowest).

[0082] A comparison of test apparatus S1 and test apparatus S4 shows that if conductive component 8 is included, the startability is improved (from evaluation B to evaluation S).

[0083] By comparing test apparatus S1 with test apparatus S2, and by comparing test apparatus S1 with test apparatus S3, it can be seen that if the trigger component 10 and the conductive component 8 are located as close as possible to the electrodes, the start-up performance is improved (from evaluation A to evaluation S).

[0084] Furthermore, in the test apparatus S2, the position where the trigger member 10 is wound is far from the conductive member 8. However, a portion 10w of the wire from the wound trigger member 10 is located on the outer periphery of the conductive member 8 (see reference). Figure 7B Even with this structure, when a pulse voltage is applied from the igniter 15, a portion 10w of the wire also functions as a trigger member 10, generating a dielectric barrier discharge at the interval between the conductive member 8 and the portion 10w of the wire. Thus, the dielectric barrier discharge disrupts the insulation between the pair of electrodes (3, 4) inside the bulb, effectively promoting arc discharge between the pair of electrodes (3, 4).

[0085] [Second Experiment]

[0086] Next, in lamp 100, based on the relationship between the interval d1 between the conductive member 8 and the trigger member 10 and the interval d4 between the front end of the cathode 4 and the cathode 4 side face of the conductive member, an experiment was conducted to investigate how the probability of insulation failure changes (second experiment). Intervals d1 and d4 are shown in the enlarged view of the main part of lamp 100. Figure 8 As shown in the figure. Test devices with different intervals d1 are fabricated by changing the size and shape of the conductive member 8. Test devices with different intervals d4 are fabricated by adjusting the Z-direction configuration of the cathode 4 and the support member 7.

[0087] In the second experiment, the output of all igniters was standardized to 22kV. Regarding the probability of insulation failure, specifically, the "10" in the denominator represents the number of times power was supplied from igniter 15 (10 times). The values ​​in the numerator represent the number of times insulation failure occurred within those 10 power supplies (i.e., the number of times the discharge lamp lit up).

[0088] [Table 2]

[0089]

[0090] The higher the insulation failure probability of the test apparatus, the better the lamp's startability. Based on the insulation failure probability, the startability of test apparatuses S11 to S15 is evaluated in three stages, S, A, and B, from best to worst. A comparison of test apparatuses S11, S13, and S15 shows that the smaller the interval d1, the better the startability. Specifically, if the interval d1 is 25mm or less, it is rated A or better and is preferred; if the interval d1 is 5mm or less, it is rated S and is further preferred. A comparison of test apparatuses S11, S12, and S14 shows that the smaller the interval d4, the better the startability. If the interval d4 is 220mm or less, it is rated A or better and is preferred; if the interval d4 is 100mm or less, it is rated S and is further preferred.

[0091] Based on the above, it can be concluded that the smaller the distance between the front end of the electrode (e.g., cathode 4) supported by the lead bar 6 in contact with the conductive member 8 and the end face of the cathode 4 side of the conductive member 8, i.e., the proximal end of the conductive member 8, the easier it is for the increase in the electric field strength based on dielectric barrier discharge to affect the arc discharge between the anode 3 and the cathode 4. The distance between the front end of the electrode supported by the lead bar 6 in contact with the conductive member 8 and the end face of the cathode 4 side of the conductive member 8, i.e., the proximal end, can be 220 mm or less, and more preferably 100 mm or less.

[0092] The smaller the interval d1 between the conductive member 8 and the trigger member 10, the better. The interval d1 can be, for example, 25 mm or less, more preferably 5 mm or less. To reduce the interval d1, the position of the trigger member 10 in the Z direction can be configured to overlap with the position of the conductive member 8 in the Z direction. When the trigger member 10 is in contact with the conductive insulating film 9, the conductive insulating film 9 has a width in the Z direction, so the position of the trigger member 10 in the Z direction and the position of the conductive member 8 in the Z direction may not overlap.

[0093] The interval d1 is less than the combined thickness of the bulb 5 and the insulation film 9. Based on this, the interval d1 can be at least 2 mm. Furthermore, when the interval d4 is too small, the conductive member 8 is not disposed on the second side tube portion 2b, and the conductive member 8 is disposed on the radially bulging light-emitting tube portion 1. If the conductive member 8 is disposed on the light-emitting tube portion 1, it may be impossible to reduce the interval d1; therefore, the interval d4 can be at least 30 mm.

[0094] Explanation of reference numerals in the attached figures

[0095] 1: Light-emitting diode section;

[0096] 2: Second side tube section;

[0097] 2a: First side tube section;

[0098] 2b: Second side tube section;

[0099] 3: Anode;

[0100] 4: Cathode;

[0101] 5: Light bulb;

[0102] 6: Lead bar;

[0103] 7, 7a, 7b: Supporting components;

[0104] 8: Conductive components;

[0105] 8h: (of a conductive component) hole;

[0106] 8p: (of a conductive component) a protrusion;

[0107] 9: Thermal insulation film;

[0108] 10: Trigger component;

[0109] 10w: (of a conductor) a portion;

[0110] 11: Fixed components;

[0111] 12: Lamp holder;

[0112] 13: Power supply line;

[0113] 15: Igniter;

[0114] 16: Power supply;

[0115] 28: Conductive components;

[0116] 100: Discharge lamp;

[0117] 200, 210, 220, 230: (Experimental) Discharge devices.

Claims

1. A discharge lamp, characterized in that have: A pair of electrodes are arranged opposite to each other in an axial direction; The light bulb comprises a light-emitting tube portion having the pair of electrodes therein, and two side tube portions respectively connected to both ends of the light-emitting tube portion in the one axial direction; two lead rods, respectively supporting the pair of electrodes; a non-conductive supporting member, located in at least one of the two side tubes, and supporting the lead rod; a conductive member located in the side tube portion having the support member therein and in contact with the lead bar; as well as The trigger component is arranged outside the light bulb and on the periphery of the conductive component.

2. The discharge lamp according to claim 1, characterized in that The thickness of the conductive member in the one axial direction is 0.4 mm or less.

3. The discharge lamp according to claim 1 or 2, characterized in that The discharge lamp includes a fixing member for fixing the conductive member. The conductive member is sandwiched between the support member and the fixing member.

4. The discharge lamp according to claim 3, characterized in that The fixing member is supported by the lead bar, and the fixing member is made of a conductive material that electrically connects the lead bar and the conductive member.

5. The discharge lamp according to claim 1 or 2, characterized in that A conductive film is provided between the conductive member and the trigger member on the outer surface of the bulb.

6. The discharge lamp according to claim 1 or 2, characterized in that The distance between the conductive member and the trigger member is less than 25 mm.

7. The discharge lamp according to claim 1 or 2, characterized in that The distance between the tip of the electrode supported by the lead bar and the conductive member, which contacts the conductive member, and the conductive member is 220 mm or less.

8. The discharge lamp according to claim 1 or 2, characterized in that The conductive member has a protrusion that protrudes radially outward in a cross section perpendicular to the one axial direction.

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