Light source device, exposure device, and method for determining light source device

Abstract

The present invention provides a light source device equipped with a determination circuit for, in an exposure device used for exposing a printed wiring board or the like, identifying whether a discharge lamp serving as a light source is a genuine product, and whether the discharge lamp is a new product or a used product at high accuracy and at low cost over a short period of time.　A light source device 100 is constituted of: a discharge lamp 110 serving as a light source; a determination circuit 200; and a reflector container 151 to which the discharge lamp 110 and the determination circuit 200 are attached. The determination circuit 200 is constituted of: an RC parallel circuit 210 to which flows DC current for detecting whether the discharge lamp 110 is a genuine product; and a fuse 220 which is connected in series to the RC parallel circuit 210 in order to determine whether the discharge lamp 110 is a new product, is resistant to being disconnected even when the DC current is flowing, and is disconnected when a current larger than the DC current flows after it has been determined whether the discharge lamp 110 is a new product.

Description

Light source device, exposure device, and determination method for light source device

[0001] The present invention relates to a light source device provided with a determination circuit for detecting whether a discharge lamp serving as a light source is a genuine product and whether it is a new product or a used product in an exposure device used for exposing a printed wiring board or the like, an exposure device using the light source device, and a determination method for the light source device.

[0002] Conventionally, a printed wiring board in which a wiring pattern is formed of a metal such as copper on a substrate made of a resin or a glass epoxy material has been used to mount components on an electronic device. A photoetching technique is used to form the wiring pattern on these printed wiring boards. Photoetching is performed by applying a photoresist, which is a photosensitive chemical, over the entire surface of a substrate on which a metal layer serving as wiring is formed over the entire surface, and irradiating the photoresist with irradiation light from an exposure device through a photomask identical to the wiring pattern.

[0003] Photoresists include a negative-type photoresist in which the solubility of the photoresist decreases due to irradiation light, and conversely, a positive-type photoresist in which the solubility of the photoresist increases due to irradiation light. By chemically treating and removing the photoresist portion whose solubility has relatively increased due to irradiation light and removing the exposed metal layer by etching, only the metal layer under the portion where the photoresist remains remains, and a wiring pattern is formed on the substrate by removing the photoresist. In the case of irradiating either positive-type or negative-type photoresist with irradiation light, in order to ensure a uniform exposure amount over the entire irradiation surface, it is necessary to irradiate with stable irradiation light at a uniform illuminance for a certain period of time.

[0004] Incidentally, in the manufacture of a printed wiring board, in order to improve the efficiency of the manufacturing process, a large printed wiring board on which a plurality of circuits are formed is produced, and after the substrate is completed, it is divided into individual circuits and used for a desired electronic device.

[0005] With the increasing size of printed circuit boards, exposure equipment manufacturers are either increasing the size of the discharge lamps used as light sources to achieve high illumination, or using multiple small, low-intensity discharge lamps to ensure the necessary illumination. For example, instead of using one 8kW high-voltage discharge lamp, four 2kW high-voltage discharge lamps are used. Low-intensity discharge lamps have advantages over high-intensity discharge lamps in terms of manufacturing difficulty and cost, and many exposure systems with multiple light sources are on the market.

[0006] However, with the increasing number of light sources, the need to ensure uniform exposure levels has made the homogeneity of multiple discharge lamps even more important. Therefore, in order to stabilize the performance of exposure equipment and manufacture highly reliable printed circuit boards, it is necessary to use only genuine discharge lamps manufactured by the same manufacturer using the same materials and methods. This necessitates equipment and methods for determining whether a discharge lamp is a genuine product.

[0007] Several methods are known for determining the discharge lamps and light sources used in optical devices, not just exposure equipment (see, for example, Patent Documents 1 to 3). For example, the lamp abnormality detection device described in Patent Document 1 supplies a predetermined voltage to an incandescent light bulb using a filament, such as a halogen lamp, and detects an abnormal lamp by comparing the current value when the filament is partially broken with the current value when the filament is normal. However, with this method, while the lifespan of the lamp can be detected, it is difficult to determine whether the lamp is a genuine product or not.

[0008] Furthermore, for example, Patent Document 2 describes a method for detecting whether a light source is an incandescent or fluorescent lamp by connecting a circuit in parallel with a light source such as an incandescent or fluorescent lamp, and measuring the time constant (product of resistance and capacitance) when a predetermined voltage is supplied across the ends of this light source. However, while this method can detect large differences in time constants (incandescent and fluorescent lamps have significantly different time constants), it is difficult to determine whether an incandescent lamp is genuine or not.

[0009] Furthermore, for example, Patent Document 3 describes detecting defective products by emitting ultraviolet light to multiple filaments enclosed within the same incandescent light bulb and measuring the discharge initiation voltage between those filaments. However, while this method can detect defective products, it is difficult to determine whether the lamp is genuine or not.

[0010] Japanese Patent Publication No. 7-52677 Publication No. 2010-527504 Publication of Japanese Patent Application Laid-Open No. 1987-43059

[0011] To determine whether a light source is a genuine product or a similar product manufactured by another company, a more accurate determination device is needed than simply identifying whether the light source is defective or not, as in Patent Documents 1 and 3, or whether it is a different type of light source, as in Patent Document 2. Furthermore, it is necessary to simultaneously address the challenges of ensuring that the inspection time for multiple light sources does not significantly exceed the startup time of the exposure system, and that the overall cost of the exposure system does not increase significantly.

[0012] Furthermore, from the perspective of ensuring uniform exposure, it is undesirable to mix new and used light sources, even if they are genuine products from the same manufacturer. For this reason, there was a need for a light source that could determine whether or not a light source was a used product that had been used at least once.

[0013] The present invention has been made in view of the aforementioned problems, and its purpose is to provide a light source device equipped with a determination circuit for determining whether a discharge lamp used as a light source is a genuine product, and whether it is new or used, in an exposure apparatus used for exposing printed circuit boards and the like, and an exposure apparatus using the light source device and a determination method therefor.

[0014] According to one aspect of the present invention, a light source device is provided comprising a discharge lamp that serves as a light source, a determination circuit, and a reflector container to which the discharge lamp and the determination circuit are attached, wherein the determination circuit includes an RC parallel circuit through which a DC current is passed to detect whether the discharge lamp is a genuine product, and a fuse connected in series with the RC parallel circuit to determine whether the discharge lamp is new, which has resistance to breakage even when the DC current is passed through it, and further breaks when a current larger than the DC current is passed through it after it has been determined whether it is new.

[0015] Furthermore, according to another aspect of the present invention, a light source device is provided comprising a discharge lamp that serves as a light source, a determination circuit, and a reflector container to which the discharge lamp and the determination circuit are mounted, wherein the determination circuit includes an RC parallel circuit through which a first DC current flows to detect whether the discharge lamp is a genuine product, and a diode connected in series with the RC parallel circuit, having resistance to being damaged even when a second DC current in the reverse direction flows to determine whether the discharge lamp is new, and further short-circuiting when a third DC current and voltage in the reverse direction, which is larger than the second DC current in the reverse direction, is applied after it has been determined whether the lamp is new.

[0016] Furthermore, according to another aspect of the present invention, a light source device is provided comprising a discharge lamp that serves as a light source, a determination circuit, and a reflector container to which the discharge lamp and the determination circuit are attached, wherein the determination circuit includes an RC parallel circuit through which a DC current is passed to detect whether the discharge lamp is a genuine product, and a diode connected in parallel to the RC parallel circuit, which has resistance to being damaged even when a second DC current in the reverse direction is passed through to determine whether the discharge lamp is new, and which shorts out when a third DC current and voltage in the reverse direction, which is larger than the second DC current in the reverse direction, is applied after it has been determined whether the lamp is new.

[0017] Furthermore, according to another aspect of the present invention, the present invention includes: a light source device as described above; a frame for mounting the light source device toward an object to be irradiated; a constant current power supply for supplying a DC current to the determination circuit; a switch for turning the current from the constant current power supply on and off; a control unit for turning the switch on and off to energize the determination circuit for a predetermined time; a measurement unit for measuring the voltage across the determination circuit at least twice while energized; a comparison unit for comparing the difference between the voltage across the circuit at the time of the first measurement and the voltage across the circuit at the time of the second measurement with a predetermined upper and lower voltage range for determining whether the discharge lamp is genuine or not; a determination unit that receives a signal from the comparison unit and determines that the discharge lamp under inspection is genuine if the difference in the voltage across the circuit is within a predetermined voltage range, and determines that the discharge lamp under inspection is not genuine if the difference in the voltage across the circuit is outside the predetermined voltage range; and, after determining whether the discharge lamp is genuine or not, a used-grade determination constant current power supply for supplying current to the determination circuit; and a used-grade determination switch for turning the current from the used-grade determination constant current power supply on and off. An exposure apparatus is provided, comprising: a used product determination control unit that turns the used product determination switch on and off to energize the determination circuit; a used product determination measurement unit that measures the voltage across the determination circuit while it is energized; a used product determination unit that determines whether the discharge lamp is new or used based on whether the measured voltage across the circuit is within a predetermined upper and lower voltage range; and a fuse blowing operation unit that, after the determination of whether it is new or used is completed, blows the fuse by flowing a current larger than the DC current.

[0018] Furthermore, according to another aspect of the present invention, the present invention includes: a light source device as described above; a frame for mounting the light source device toward an object to be irradiated; a constant current power supply that supplies a first DC current forward to the diode to the determination circuit; a switch for turning the current from the constant current power supply on and off; a control unit that turns the switch on and off to energize the determination circuit for a predetermined time; a measurement unit that measures the voltage across the determination circuit at least twice while energized; a comparison unit that compares the difference between the voltage across the terminals at the time of the first measurement and the voltage across the terminals at the time of the second measurement with a predetermined upper and lower voltage range for determining whether the discharge lamp is genuine or not; a determination unit that receives a signal from the comparison unit and determines that the discharge lamp under inspection is genuine if the difference in the voltage across the terminals is within a predetermined voltage range, and determines that the discharge lamp under inspection is not genuine if the difference in the voltage across the terminals is outside the predetermined voltage range; and a used-grade determination constant current power supply that supplies a second DC current reverse to the diode to the determination circuit after determining whether the discharge lamp is genuine or not. An exposure apparatus is provided, comprising: a used-item determination switch for turning on and off the current from the used-item determination constant current power supply; a used-item determination control unit for turning on and off the used-item determination switch to energize the determination circuit; a used-item determination measurement unit for measuring the voltage across the determination circuit while it is energized; a used-item determination unit for determining whether the discharge lamp is new or used based on whether the measured voltage across the circuit is within a predetermined upper and lower voltage range; and a reverse voltage application unit for short-circuiting the diode by applying a third DC current and voltage in the reverse direction that is larger than the second DC current after the determination of whether it is new or used is completed.

[0019] Furthermore, according to another aspect of the present invention, the present invention includes: a light source device as described above; a frame for mounting the light source device toward an object to be irradiated; a constant current power supply that supplies a first DC current to the determination circuit in the opposite direction to the diode; a switch for turning the current from the constant current power supply on and off; a control unit that turns the switch on and off to energize the determination circuit for a predetermined time; a measurement unit that measures the voltage across the determination circuit at least twice while energized; a comparison unit that compares the difference between the voltage across the circuit at the time of the first measurement and the voltage across the circuit at the time of the second measurement with a predetermined upper and lower voltage range for determining whether the discharge lamp is genuine or not; a determination unit that receives a signal from the comparison unit and determines that the discharge lamp under inspection is genuine if the difference in the voltage across the circuit is within a predetermined voltage range, and determines that the discharge lamp under inspection is not genuine if the difference in the voltage across the circuit is outside a predetermined voltage range; and a used-grade determination constant current power supply that supplies a second DC current to the determination circuit in the opposite direction to the diode after determining whether the discharge lamp is genuine or not. An exposure apparatus is provided, comprising: a used-item determination switch for turning on and off the current from the used-item determination constant current power supply; a used-item determination control unit for turning on and off the used-item determination switch to energize the determination circuit; a used-item determination measurement unit for measuring the voltage across the determination circuit while it is energized; a used-item determination unit for determining whether the discharge lamp is new or used based on whether the measured voltage across the circuit is within a predetermined upper and lower voltage range; and a reverse voltage application unit for short-circuiting the diode by applying a third DC current and voltage in the reverse direction that is larger than the second DC current after the determination of whether it is new or used is completed.

[0020] Furthermore, according to another aspect of the present invention, a method for determining a light source device is provided, which involves applying a DC current to the determination circuit of the light source device described above for a predetermined time, measuring the voltage across the determination circuit at least twice while the current is flowing, comparing the difference between the voltage across the circuit at the time of the first measurement and the voltage across the circuit at the time of the second measurement with a predetermined upper and lower voltage range for determining whether the discharge lamp is genuine or not, determining that the discharge lamp to be determined is genuine if the difference in the voltage across the circuit is within the predetermined voltage range, and determining that the discharge lamp to be determined is not genuine if the difference in the voltage across the circuit is outside the predetermined voltage range, and then, after determining whether the discharge lamp is genuine or not, applying current to the determination circuit, measuring the voltage across the determination circuit while the current is flowing, determining that the discharge lamp to be determined is new if the measured voltage across the circuit is within the predetermined upper and lower voltage range, and determining that the discharge lamp to be determined is used if it is outside the predetermined upper and lower voltage range, and then blowing the fuse by flowing a current larger than the DC current.

[0021] Furthermore, according to another aspect of the present invention, a first DC current forward to the diode is applied to the determination circuit of the light source device described above for a predetermined time, the voltage across the determination circuit is measured at least twice while the current is applied, the difference between the voltage across the circuit at the time of the first measurement and the voltage across the circuit at the time of the second measurement is compared with a predetermined upper and lower voltage range for determining whether the discharge lamp is genuine or not, if the difference in the voltage across the circuit is within the predetermined voltage range, it is determined that the discharge lamp to be judged is a genuine product, if the difference in the voltage across the circuit is outside the predetermined voltage range, it is determined that the discharge lamp to be judged is not a genuine product, and after determining whether the discharge lamp is genuine or not, a second DC current reverse to the diode is applied to the determination circuit, the voltage across the determination circuit is measured while the current is applied, if the measured voltage across the circuit is within the predetermined upper and lower voltage range, it is determined that the discharge lamp to be judged is new, if it is outside the predetermined upper and lower voltage range, it is determined that the discharge lamp to be judged is used, A method is provided for determining whether a light source device short-circuits the diode by applying a third DC current and voltage in the opposite direction that is larger than the second DC current.

[0022] Furthermore, according to another aspect of the present invention, a first DC current in the reverse direction to the diode is passed through the determination circuit of the light source device described above for a predetermined time, the voltage across the determination circuit is measured at least twice while the current is flowing, the difference between the voltage across the circuit at the time of the first measurement and the voltage across the circuit at the time of the second measurement is compared with a predetermined upper and lower voltage range for determining whether the discharge lamp is genuine or not, if the difference in the voltage across the circuit is within the predetermined voltage range, it is determined that the discharge lamp to be determined is a genuine product, if the difference in the voltage across the circuit is outside the predetermined voltage range, it is determined that the discharge lamp to be determined is not a genuine product, and after determining whether the discharge lamp is genuine or not, a second DC current in the reverse direction to the diode is passed through the determination circuit, the voltage across the determination circuit is measured while the current is flowing, if the measured voltage across the circuit is within the predetermined upper and lower voltage range, it is determined that the discharge lamp to be determined is new, if it is outside the predetermined upper and lower voltage range, it is determined that the discharge lamp to be determined is used, A method is provided for determining whether a light source device short-circuits the diode by applying a third DC current and voltage in the opposite direction that is larger than the second DC current.

[0023] According to the present invention, we have been able to provide a light source device equipped with a determination circuit for determining whether the discharge lamp used as a light source is a genuine product, and whether it is new or used, in an exposure apparatus used for exposing printed circuit boards and the like, in high accuracy, in a short time, and at low cost, as well as an exposure apparatus using the light source device and a determination method.

[0024] This figure shows an example of an exposure machine 10 to which the present invention is applied. This figure shows an example of an exposure apparatus 50 to which the present invention is applied. This is a plan view showing an example of an exposure apparatus 50 to which the present invention is applied. This is a cross-sectional view showing an example of a light source device 100 to which the present invention is applied. This is a cross-sectional view showing an example of a discharge lamp 110. This figure shows an example of a determination device 57 to which the present invention is applied. This is a cross-sectional view showing an example of a light source device 100 according to modification 1 to which the present invention is applied. This is a cross-sectional view showing an example of a light source device 100 according to modification 2 to which the present invention is applied. This is a cross-sectional view showing another embodiment regarding the arrangement position of the determination circuit 200. This is a cross-sectional view showing another embodiment regarding the arrangement position of the determination circuit 200.

[0025] (Example 1) (Configuration of exposure machine 10) Figure 1 shows an exposure machine 10 according to Example 1 to which the present invention is applied. The exposure machine 10 is generally composed of an exposure device 50, an integrator 12, a concave mirror 14, and an irradiation surface 16.

[0026] The exposure apparatus 50 emits light containing wavelengths suitable for exposure of the object X to be exposed. Details of the exposure apparatus 50 will be explained after the configuration of the exposure machine 10 is described.

[0027] The integrator 12 has an incident surface 18 that receives light from the exposure apparatus 50, and an exit surface 20 that emits the received light after improving its uniformity. Multiple fly-eye lenses 21 are formed on the incident surface 18 and the exit surface 20, respectively.

[0028] The concave mirror 14 has a reflective concave surface 22 on its inside. This concave mirror 14 reflects the light emitted from the integrator 12 with the reflective concave surface 22 to make it parallel light.

[0029] The illumination surface 16 receives parallel light from the concave mirror 14 and is positioned approximately perpendicular to the parallel light. An object to be exposed X is placed on this illumination surface 16. For example, a photosensitive material is coated on the surface of the object to be exposed X. By illuminating a desired area of ​​the object to be exposed X with parallel light from the concave mirror 14, a desired circuit pattern or the like is formed on the surface of the object to be exposed X.

[0030] (Configuration of the exposure apparatus 50) Figure 2 is a diagram showing an exposure apparatus 50 according to Embodiment 1 to which the present invention is applied. Figure 3 is a plan view of the exposure apparatus 50. The exposure apparatus 50 comprises a plurality of light source devices 100, a frame 52, a lighting circuit 54, a switch 55, a constant current power supply 56, a determination device 57, a used constant current power supply 76 for used determination, and a used determination switch 78. Note that the switch 55 and the used determination switch 78, and the constant current power supply 56 and the used constant current power supply 76 may be physically the same and configured to share functions, or physically different components may be provided for each.

[0031] The light source device 100 emits light containing wavelengths suitable for exposing the object X to be exposed. As shown in Figure 4, the light source device 100 is generally composed of a discharge lamp 110, a reflector 150, an insulating base 170, and a determination circuit 200. The reflector 150 and the insulating base 170 are sometimes collectively referred to as the reflector container 151.

[0032] As shown in Figure 5, the discharge lamp 110 has a discharge tube portion 112 and a pair of sealing portions 114 extending from the discharge tube portion 112. The discharge tube portion 112 and the pair of sealing portions 114 are integrally formed from quartz glass. Furthermore, an internal space 116 sealed by the sealing portions 114 is formed inside the discharge tube portion 112.

[0033] Each seal portion 114 of the discharge lamp 110 is provided with an embedded molybdenum foil 118, a pair of tungsten electrodes 120 with one end connected to one end of the foil 118 and the other end positioned in the internal space 116, and a pair of lead rods 122 with one end connected to the other end of the foil 118 and the other end extending outward from the seal portion 114. The internal space 116 is sealed with a predetermined amount of mercury 124 and a halogen (for example, bromine).

[0034] When a predetermined high voltage is applied to a pair of lead rods 122 provided in the discharge lamp 110, the glow discharge that started between a pair of electrodes 120 provided in the internal space 116 of the discharge tube section 112 transitions to an arc discharge, and light (mainly ultraviolet light) is emitted by the mercury 124 that is evaporated and excited by this arc.

[0035] Returning to Figure 4, in the light source device 100 according to this embodiment, one of the seal portions 114 is inserted into the seal portion insertion hole 156 of the reflector 150. Note that the discharge lamp 110 may be for AC or DC operation.

[0036] The reflector 150 has a bowl-shaped reflective surface 152 on its inner surface. This reflective surface 152 reflects a portion of the light from the discharge lamp 110, which is positioned so that the discharge tube portion 112 is located inside the reflector 150. In this embodiment, this reflective surface 152 is defined as a paraboloid of revolution. Furthermore, the light emission point of the discharge lamp 110 (roughly the central position of the arc formed between the pair of electrodes 120 in the internal space 116) coincides with the focal point of the paraboloid of revolution. As a result, the light emitted from the light emission point of the discharge lamp 110, reflected by the reflective surface 152, and then exiting the aperture 154 of the reflector 150 becomes approximately parallel light. Of course, the shape of the reflective surface 152 is not limited to this, and it may be an ellipsoid of revolution, another surface of revolution, or a shape other than a surface of revolution. Also, it is not essential to make the light emission point coincide with the focal point, and the light emission point may be shifted from the focal point as needed.

[0037] Furthermore, a bottom neck portion 155 is provided protruding from the side of the reflector 150 opposite to the opening 154. In addition, a seal portion insertion hole 156 is formed in the reflective surface 152 of the reflector 150, into which one of the seal portions 114 of the discharge lamp 110 is inserted. This seal portion insertion hole 156 is formed from the bottom of the reflective surface 152 to the tip of the bottom neck portion 155.

[0038] As shown in Figure 1, by combining the discharge lamp 110 with the reflector 150, the light emitted from the discharge lamp 110 will travel in front of the reflector 150 within a range with a predetermined angle (opening angle) centered on the light traveling along the central axis CL of the reflective surface 152.

[0039] Returning to Figure 4, the insulating base 170 is made of an electrical insulator such as ceramic, and has a reflector insertion hole 172 into which one of the seal portions 114 of the discharge lamp 110, which is inserted into the bottom neck portion 155 of the reflector 150 and the seal portion insertion hole 156, is inserted. When the bottom neck portion 155 and the seal portion 114 are inserted into the reflector insertion hole 172, the insulating base 170 covers the seal portion insertion hole 156 from the outside.

[0040] Furthermore, the insulating base 170 has an inner space 174 that communicates with the reflector insertion hole 172 described above, and a power cable insertion hole 176 is formed that connects the inner space 174 and the outside to each other, through which the power cable A is inserted.

[0041] Furthermore, the insulating base 170 and the discharge lamp 110 (and in this embodiment, the determination circuit 200) are fixed to each other by an inorganic adhesive C having electrical insulation and high thermal conductivity. Specifically, the end of the bottom neck portion 155 of the reflector 150 and one of the sealing portions 114 of the discharge lamp 110 are inserted into the reflector insertion hole 172 of the insulating base 170, and the determination circuit 200 and power cable A are placed in the inner space 174 of the insulating base 170, with the inorganic adhesive C filled into the inner space 174.

[0042] In this embodiment, the determination circuit 200 includes an RC parallel circuit 210 and a fuse 220. The RC parallel circuit 210 is a circuit formed by connecting a resistor 212 and a capacitor 214 in parallel with each other.

[0043] The fuse 220 is a component connected in series with the RC parallel circuit 210. In this embodiment, the capacity of the fuse 220 is set so that it does not break when a constant current is passed through it to determine whether the discharge lamp 110 is a genuine product, as will be described later, but after the initial determination of whether it is a used product, it breaks when a current larger than the constant current is passed through it by the fuse breakage operation unit 67. Alternatively, a fuse 220 that breaks due to the heat from the discharge lamp 110 while it is lit, i.e., a "thermal fuse," may be used.

[0044] Returning to FIG. 3, the frame 52 is a substantially rectangular parallelepiped member in which a plurality of recesses 58 for mounting a plurality of light source devices 100 are formed.

[0045] Returning to FIG. 2, the lighting circuit 54 is a circuit that supplies power necessary for the discharge lamp 110 of each light source device 100 attached to the frame 52. Also, the constant current power source 56 and the used determination constant current power source 76 are power sources that supply a DC constant current to the determination circuit 200 of each light source device 100, and the switch 55 and the used determination switch 78 turn on and off the DC constant current supplied to the determination circuit 200.

[0046] The determination device 57 is a device for determining whether each light source device 100 (discharge lamp 110) is a genuine product and whether each light source device 100 (discharge lamp 110) is new or used. As shown in FIG. 6, it generally has a control unit 60, a measurement unit 62, a comparison unit 64, a determination unit 66, a fuse blow operation unit 67, a used determination control unit 68, a used determination measurement unit 70, and a used determination unit 72. Note that the control unit 60 and the used determination control unit 68, the measurement unit 62 and the used determination measurement unit 70, and the determination unit 66 and the used determination unit 72 may be set so that physically the same ones share functions, or separate ones may be prepared.

[0047] The control unit 60 has a function of operating the switch 55 to turn on and off the current supplied from the constant current power source 56 to the determination circuit 200.

[0048] The measurement unit 62 has a function of measuring the voltage across both ends of the determination circuit 200. In the case of this embodiment, the measurement unit 62 is configured to measure the voltage across both ends of the determination circuit 200 during energization at least twice.

[0049] The comparison unit 64 has a function of comparing the difference between the voltage across both ends of the determination circuit 200 at the first measurement and the voltage across both ends at the second measurement measured by the measurement unit 62 with the voltage range of a predetermined upper limit value and a lower limit value for determining whether the discharge lamp 110 is a genuine product. A voltage distribution range of a plurality of RC parallel circuits 210 for detecting genuine products measured under predetermined conditions is recorded in the comparison unit 64, and the comparison unit 64 transmits the signal of the above comparison result to the determination unit 66.

[0050] The determination unit 66 receives the result signal transmitted from the comparison unit 64 and determines that the discharge lamp 110 to be inspected is a genuine product if the difference in voltage across both ends is within a predetermined voltage range, and conversely, determines that the discharge lamp 110 to be inspected is not a genuine product if the difference in voltage across both ends is outside the predetermined voltage range.

[0051] The used product detection control unit 68 has the function of turning on and off the current supplied from the used product detection constant current power supply 76 to the detection circuit 200 by operating the used product detection switch 78 after determining that the product is genuine.

[0052] The used item determination measurement unit 70 has the function of measuring the voltage across the determination circuit 200 while it is energized.

[0053] The used item determination unit 72 has the function of determining whether the discharge lamp 110 is new or used based on whether the voltage across both ends measured by the used item determination measurement unit 70 is within a predetermined upper and lower voltage range. That is, if the voltage across both ends measured by the used item determination measurement unit 70 is within a predetermined upper and lower voltage range, the used item determination unit 72 determines that the discharge lamp 110 is new. Conversely, if the voltage across both ends measured by the used item determination measurement unit 70 is outside the predetermined upper and lower voltage range, the used item determination unit 72 determines that the discharge lamp 110 is used.

[0054] After the used item determination unit 72 determines whether the discharge lamp 110 is a used item or not, the fuse break operation unit 67 sends a current to the determination circuit 200 that is larger than the constant current used for genuine item determination and used item determination. As a result, the fuse 220 breaks, the determination circuit 200 becomes open, and the resistance value across the determination circuit 200 becomes infinite.

[0055] (Operation of the exposure apparatus 50) When the power switch (not shown) of the exposure apparatus 50 is turned on, the lighting circuit 54 supplies power to the discharge lamps 110 in all the light source devices 100 mounted on the frame 52. Normally, it takes several minutes for the discharge lamps 110 to fully warm up.

[0056] For example, immediately after the power switch of the exposure apparatus 50 is turned on, the control unit 60 in the determination device 57 turns on a switch 55 connected to a determination circuit 200 in one of the light source devices 100 mounted on the frame 52, and supplies a constant current to the determination circuit 200 from the constant current power supply 56. Of course, the timing of the operation of the determination device 57 is not limited to this.

[0057] Immediately after the switch 55 is turned on for the first time, the measurement unit 62 measures the voltage across the determination circuit 200 and sends the result (first measurement) to the comparison unit 64. Next, a predetermined time after the first measurement (for example, 10 seconds later), a constant current is supplied to the same determination circuit 200 again, the measurement unit 62 measures the voltage across the determination circuit 200 and sends the result (second measurement) to the comparison unit 64.

[0058] The comparison unit 64, having received the results of two voltage measurements across both ends, sends a result signal to the determination unit 66 to determine whether the difference between the two measured voltages is within a pre-recorded voltage difference range. If the difference between the voltages across both ends is within a predetermined voltage range, the determination unit 66 determines that the discharge lamp 110 being inspected is a genuine product. Conversely, if the difference between the voltages across both ends is outside the predetermined voltage range, the determination unit 66 determines that the discharge lamp 110 being inspected is not a genuine product.

[0059] When a constant DC current is passed through the RC parallel circuit 210, at the initial stage when no charge has been stored in the capacitor 214, current flows through the capacitor 214 and the resistor 212. Therefore, the voltage across the RC parallel circuit 210 is determined based on the combined impedance of the capacitor 214 and the resistor 212. The first measurement of the voltage across the judgment circuit 200 by the measurement unit 62 is performed at this timing.

[0060] After a constant DC current is passed through the RC parallel circuit 210 for a while, the capacitor 214 becomes fully charged, and no current flows through it. When no current flows through the capacitor 214, the voltage across the RC parallel circuit 210 is determined based on the resistance value of the resistor 212 alone. The second measurement of the voltage across the judgment circuit 200 by the measurement unit 62 is performed at this timing. Generally, the resistance value of the resistor 212 alone is greater than the combined impedance of the capacitor 214 and the resistor 212. Since a constant current flows through the RC parallel circuit 210, the voltage across the RC parallel circuit 210 when the resistance value is that of the resistor 212 alone (second measurement) is greater than the voltage across the RC parallel circuit 210 when the combined impedance of the capacitor 214 and the resistor 212 is used (first measurement).

[0061] Conversely, if the product is not genuine, the first and second measurement results will be identical or nearly identical. This allows the determination of whether the light source device 100 (discharge lamp 110) is genuine or not using the method described above. Alternatively, the determination of whether the product is genuine or not can be made by measuring the voltage across both ends only at the timing of the second measurement described above. In this case, the determination of whether the product is genuine or not will be made based on whether the measured voltage across both ends falls within a predetermined voltage range.

[0062] Even if it is a genuine part, if it is a used part, as will be explained later, the fuse 220 will be broken and the determination circuit 200 will be open, so the result of the first measurement and the result of the second measurement will be the same (maximum voltage of the constant current power supply 56). In this way, if the result of the first measurement and the result of the second measurement are the same and the measurement result is the maximum voltage value of the constant current power supply 56, it will also be determined to be a genuine part.

[0063] After the genuine product determination of the first light source device 100 is completed, the control unit 60 starts supplying a constant current to the determination circuit 200 of the other light source devices 100. Thereafter, the genuine product determination is performed in the same manner as in the first case described above, and the same determination is repeated until the determination of all light source devices 100 is completed, or until the inspection of a predetermined range of light source devices 100 is completed.

[0064] Subsequently, the used equipment determination control unit 68 in the determination device 57 turns on the used equipment determination switch 78 connected to the determination circuit 200 in one of the light source devices 100, and supplies a constant current from the used equipment determination constant current power supply 76 to the determination circuit 200. Immediately after turning on the used equipment determination switch 78, the used equipment determination measurement unit 70 measures the voltage across the determination circuit 200 and sends the result to the used equipment determination unit 72.

[0065] The used item determination unit 72 determines whether the discharge lamp 110 is new or used based on whether the measured voltage is within a predetermined upper and lower voltage range.

[0066] In this embodiment, if the voltage across both ends measured by the used product determination measurement unit 70 is within the predetermined upper and lower voltage ranges, the used product determination unit 72 determines that the discharge lamp 110 is new. Conversely, if the voltage across both ends measured by the used product determination measurement unit 70 is outside the predetermined upper and lower voltage ranges, the used product determination unit 72 determines that the discharge lamp 110 is a used product. If the light source device 100 is a genuine product and has been used at least once (i.e., a used product), the fuse 220 in the determination circuit 200 has already been blown by the fuse break operation unit 67, as described later, so the determination circuit 200 is in an open state (resistance = infinite). For this reason, the maximum voltage of the used product determination constant current power supply 76 is applied to the voltage across both ends of the determination circuit 200. By setting the predetermined upper limit to be smaller than this "maximum voltage of the used product determination constant current power supply 76", the used product determination measurement unit 70 can determine if the determination circuit 200 is open and it is a used product.

[0067] After the necessary used product determination is completed, the fuse-opening operation unit 67 in the determination device 57 supplies a current (for example, 30V, 1.4A) to the determination circuit 200 that is larger than the constant current used for genuine product determination and used product determination. As a result, the fuse 220 opens, and the determination circuit 200 becomes open, and the resistance value across the determination circuit 200 becomes infinite.

[0068] Up to this point, we have described an example in which genuine product determination is performed on all light source devices 100 attached to the exposure apparatus 50 before starting used product determination. However, it is also possible to perform genuine product determination and used product determination on one light source device 100 consecutively, and then perform genuine product determination and used product determination on the other light source devices 100 consecutively. Of course, it is also possible to group multiple light source devices 100 together and perform genuine product determination sequentially, and then use product determination sequentially. This is also the case in the following modified examples. Furthermore, after genuine product determination, used product determination may be performed after approximately 2000 hours of use.

[0069] (Features of the exposure apparatus 50) According to this embodiment, we have been able to provide a light source device 100 equipped with a determination circuit 200 for determining whether the discharge lamp 110, which serves as the light source, is a genuine product, and whether it is new or used, with high accuracy, in a short time and at low cost, as well as an exposure apparatus 50 using the light source device 100 and a method for determining this.

[0070] (Modification 1) In the above embodiment, the determination circuit 200 of the light source device 100 was composed of an RC parallel circuit 210 and a fuse 220. However, as shown in Figure 7, a diode 230 may be connected in series with the RC parallel circuit 210 instead of the fuse 220.

[0071] In this case, the determination of the genuine product of the light source device 100 is the same as in Example 1 (however, note that the current flowing from the constant current power supply 56 to the determination circuit 200 is the forward DC of the diode 230), so the explanation will be omitted by referring to the procedure for determining the genuine product in Example 1.

[0072] Next, the used item determination unit 72 determines whether the discharge lamp 110 is a used item or a new item based on whether the measured voltage is within a predetermined upper and lower voltage range.

[0073] In the case of Modification 1, the determination of whether the light source device 100 according to Modification 1 is a used item is the reverse of that in Embodiment 1 described above. As a premise, the current that flows from the constant current power supply 56 to the determination circuit 200 is DC in the reverse direction of the diode 230. That is, if the voltage across both ends measured by the used item determination measurement unit 70 is within the predetermined upper and lower voltage ranges, the used item determination unit 72 determines that the discharge lamp 110 is a used item. Conversely, if the voltage across both ends measured by the used item determination measurement unit 70 is outside the predetermined upper and lower voltage ranges, the used item determination unit 72 determines that the discharge lamp 110 is a new item.

[0074] If the light source device 100 according to Modification 1 is a genuine product and has been used at least once (i.e., a used product), then, as described later, the diode 230 in the determination circuit 200 is already short-circuited by the reverse voltage application unit 80, so the determination circuit 200 is in the same state as if it were composed only of an RC parallel circuit 210. For this reason, the voltage across the determination circuit 200 is within the predetermined upper and lower voltage ranges.

[0075] Conversely, if the light source device 100 according to Modification 1 is a genuine product and is new, no DC current flows in the reverse direction of the diode 230 through the determination circuit 200, and therefore the maximum voltage of the used product determination constant current power supply 76 is applied to the determination circuit 200. By setting a predetermined upper limit to be smaller than this "maximum voltage of the used product determination constant current power supply 76", the used product determination measurement unit 70 can determine whether the diode 230 is short-circuited.

[0076] After the used item inspection, in this modified example 1, a reverse voltage application unit 80 is used instead of the fuse break operation unit 67 in Example 1. This reverse voltage application unit 80 has the function of applying a reverse voltage (DC) to the diode 230 (inspection circuit 200) that is strong enough to damage the diode 230. After the used item inspection of the light source device 100 is completed, this reverse voltage application unit 80 is activated to damage the diode 230 with the reverse voltage. As a result, the diode 230 shorts out internally and loses its function, and the inspection circuit 200 becomes the same as if it were composed only of an RC parallel circuit 210.

[0077] (Modification 2) Alternatively, as shown in Figure 8, the diode 230 may be connected in parallel to the RC parallel circuit 210. In this case, the determination of whether the light source device 100 is genuine is the same as in Example 1 (however, note that the current flowing from the constant current power supply 56 to the determination circuit 200 is DC in the reverse direction of the diode 230), so the explanation will be omitted by referring to the procedure for determining genuine product in Example 1.

[0078] Next, the used item determination unit 72 determines whether the discharge lamp 110 is new or used based on whether the measured voltage across the determination circuit 200 is within a predetermined upper and lower voltage range. In this embodiment, if the voltage across the terminals measured by the used item determination measurement unit 70 is within the predetermined upper and lower voltage range, the used item determination unit 72 determines that the discharge lamp 110 is new. Conversely, if the voltage across the terminals measured by the used item determination measurement unit 70 is outside the predetermined upper and lower voltage range, the used item determination unit 72 determines that the discharge lamp 110 is used.

[0079] If the light source device 100 is a used item, the diode 230 in the detection circuit 200 is already short-circuited by the reverse voltage application unit 80, as described later, so the detection circuit 200 is short-circuited (with a very low resistance). For this reason, in the case of a used item, when current is passed in the reverse direction through the diode 230, the voltage across the detection circuit 200 is 1V or less. If the light source device 100 is new, the diode 230 has not lost its function, so no current flows in the reverse direction through the diode 230, and the current flows only through the RC parallel circuit 210. In other words, the detection circuit 200 is in the same state as the RC parallel circuit 210 alone, so the voltage across the detection circuit 200 is greater than 1V (for example, from 2.0V to 8.5V). As a result, the used condition of the light source device 100 can be determined by passing current in the reverse direction through the diode 230 to the detection circuit 200.

[0080] After confirming whether the light source device 100 is a used item or not, a large reverse voltage (DC) is applied to the diode 230 by the reverse voltage application unit 80, causing the diode 230 to short-circuit internally and lose its function, and the determination circuit 200 enters a short-circuit state.

[0081] (Modification 4) In the above-described embodiment and modification, the determination circuit 200 is housed inside the reflector container 151. However, the location of the determination circuit 200 is not limited to this. For example, it may be located on the outside side of the reflector container 151 (Figure 9), or on the outside (back side) of the reflector 150 (Figure 10).

[0082] The embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. The scope of the present invention is indicated by the claims rather than by the foregoing description, and all modifications within the meaning and scope equivalent to the claims are intended to be included.

[0083] 10... Exposure machine, 12... Integrator, 14... Concave mirror, 16... Irradiation surface, 18... Incident surface, 20... Exit surface, 21... Fly-eye lens, 22... Reflective concave surface 50... Exposure device, 52... Frame, 54... Lighting circuit, 55... Switch, 56... Constant current power supply, 57... Judgment device, 58... Recess, 60... Control unit, 62... Measurement unit, 64... Comparison unit, 66... ​​Judgment unit, 67... Fuse break operation unit, 68... Used equipment judgment control unit, 70... Used equipment judgment measurement unit, 72... Used equipment judgment unit, 76... Used equipment judgment constant current power supply, 78... Used equipment judgment switch 80... Reverse voltage application unit, 100... Light source device, 110... Discharge lamp, 112... Discharge tube unit, 114... Seal unit, 116... Internal space, 118... Foil, 120... Electrode, 122... Lead rod, 124... Mercury 150...Reflector, 151...Reflector container, 152...Reflective surface, 154...Opening, 155...Bottom neck, 156...Seal insertion hole, 170...Insulating base, 172...Reflector insertion hole, 174...Inner space, 176...Power cable insertion hole, 200...Determination circuit, 210...RC parallel circuit, 212...Resistor, 214...Capacitor, 220...Fuse, 230...Diode

Claims

1. A light source device comprising a discharge lamp that serves as a light source, a determination circuit, and a reflector container to which the discharge lamp and the determination circuit are mounted, wherein the determination circuit comprises an RC parallel circuit through which a DC current is passed to detect whether the discharge lamp is a genuine product, and a fuse connected in series with the RC parallel circuit to determine whether the discharge lamp is new, which has resistance to not breaking even when the DC current is passed through it, and further breaks when a current larger than the DC current is passed through it after it has been determined whether it is new or not.

2. A light source device comprising a discharge lamp that serves as a light source, a determination circuit, and a reflector container to which the discharge lamp and the determination circuit are mounted, wherein the determination circuit comprises an RC parallel circuit through which a first DC current flows to detect whether the discharge lamp is a genuine product, and a diode connected in series with the RC parallel circuit, having resistance to being damaged even when a second DC current in the reverse direction flows to determine whether the discharge lamp is new, and further short-circuiting when a third DC current and voltage in the reverse direction that is larger than the second DC current in the reverse direction is applied after it has been determined whether the lamp is new.

3. A light source device comprising a discharge lamp that serves as a light source, a determination circuit, and a reflector container to which the discharge lamp and the determination circuit are mounted, wherein the determination circuit comprises an RC parallel circuit through which a DC current is passed to detect whether the discharge lamp is a genuine product, and a diode connected in parallel to the RC parallel circuit, having resistance to being damaged even when a second DC current in the reverse direction is passed through to determine whether the discharge lamp is new, and further having short-circuit when a third DC current and voltage in the reverse direction that is larger than the second DC current in the reverse direction is applied after it has been determined whether it is new.

4. A light source device according to claim 1; a frame for mounting the light source device toward an object to be irradiated; a constant current power supply for supplying a DC current to the determination circuit; a switch for turning the current from the constant current power supply on and off; a control unit for turning the switch on and off to energize the determination circuit for a predetermined time; a measuring unit for measuring the voltage across the determination circuit at least twice while energized; a comparison unit for comparing the difference between the voltage across the circuit at the time of the first measurement and the voltage across the circuit at the time of the second measurement with a predetermined upper and lower voltage range for determining whether the discharge lamp is genuine or not; a determination unit that receives a signal from the comparison unit and determines that the discharge lamp to be inspected is genuine if the difference in the voltage across the circuit is within a predetermined voltage range, and determines that the discharge lamp to be inspected is not genuine if the difference in the voltage across the circuit is outside the predetermined voltage range; a used-condition determination constant current power supply for supplying current to the determination circuit after determining whether the discharge lamp is genuine or not; a used-condition determination switch for turning the current from the used-condition determination constant current power supply on and off; An exposure apparatus comprising: a used product determination control unit that turns the used product determination switch on and off to energize the determination circuit; a used product determination measurement unit that measures the voltage across the determination circuit while it is energized; a used product determination unit that determines whether the discharge lamp is new or used based on whether the measured voltage across the circuit is within a predetermined upper and lower voltage range; and a fuse blowing operation unit that, after the determination of whether it is new or used is completed, blows the fuse by flowing a current larger than the DC current.

5. A light source device according to claim 2; a frame for mounting the light source device toward an object to be irradiated; a constant current power supply that supplies a first DC current forward to the diode to the determination circuit; a switch for turning the current from the constant current power supply on and off; a control unit that turns the switch on and off to energize the determination circuit for a predetermined time; a measuring unit that measures the voltage across the determination circuit at least twice while energized; a comparison unit that compares the difference between the voltage across the terminals at the time of the first measurement and the voltage across the terminals at the time of the second measurement with a predetermined upper and lower voltage range for determining whether the discharge lamp is genuine or not; a determination unit that receives a signal from the comparison unit and determines that the discharge lamp to be inspected is genuine if the difference in the voltage across the terminals is within a predetermined voltage range, and determines that the discharge lamp to be inspected is not genuine if the difference in the voltage across the terminals is outside a predetermined voltage range; a used-grade determination constant current power supply that supplies a second DC current reverse to the diode to the determination circuit after determining whether the discharge lamp is genuine or not; An exposure apparatus comprising: a used-item determination switch for turning on and off the current from the constant current power supply for used-item determination; a used-item determination control unit for turning on and off the used-item determination switch to energize the determination circuit; a used-item determination measurement unit for measuring the voltage across the determination circuit while it is energized; a used-item determination unit for determining whether the discharge lamp is new or used based on whether the measured voltage across the circuit is within a predetermined upper and lower voltage range; and a reverse voltage application unit for short-circuiting the diode by applying a third DC current and voltage in the reverse direction that is greater than the second DC current after the determination of whether it is new or used is completed.

6. A light source device according to claim 3; a frame for mounting the light source device toward an object to be irradiated; a constant current power supply that supplies a first DC current to the determination circuit in the opposite direction to the diode; a switch for turning the current from the constant current power supply on and off; a control unit that turns the switch on and off to energize the determination circuit for a predetermined time; a measuring unit that measures the voltage across the determination circuit at least twice while energized; a comparison unit that compares the difference between the voltage across the circuit at the time of the first measurement and the voltage across the circuit at the time of the second measurement with a predetermined upper and lower voltage range for determining whether the discharge lamp is genuine or not; a determination unit that receives a signal from the comparison unit and determines that the discharge lamp to be inspected is genuine if the difference in the voltage across the circuit is within a predetermined voltage range, and determines that the discharge lamp to be inspected is not genuine if the difference in the voltage across the circuit is outside a predetermined voltage range; a used-grade determination constant current power supply that supplies a second DC current to the determination circuit in the opposite direction to the diode after determining whether the discharge lamp is genuine or not; An exposure apparatus comprising: a used-item determination switch for turning on and off the current from the constant current power supply for used-item determination; a used-item determination control unit for turning on and off the used-item determination switch to energize the determination circuit; a used-item determination measurement unit for measuring the voltage across the determination circuit while it is energized; a used-item determination unit for determining whether the discharge lamp is new or used based on whether the measured voltage across the circuit is within a predetermined upper and lower voltage range; and a reverse voltage application unit for short-circuiting the diode by applying a third DC current and voltage in the reverse direction that is greater than the second DC current after the determination of whether it is new or used is completed.

7. A method for determining whether a light source device is genuine or not, comprising: applying a DC current to the determination circuit of the light source device described in claim 1 for a predetermined time; measuring the voltage across the determination circuit at least twice while the current is applied; comparing the difference between the voltage across the circuit at the time of the first measurement and the voltage across the circuit at the time of the second measurement with a predetermined upper and lower voltage range for determining whether a discharge lamp is genuine or not; determining that the discharge lamp to be determined is genuine if the difference in the voltage across the circuit is within the predetermined voltage range; determining that the discharge lamp to be determined is not genuine if the difference in the voltage across the circuit is outside the predetermined voltage range; further determining whether the discharge lamp is genuine or not, after determining whether the discharge lamp is genuine or not, applying current to the determination circuit, measuring the voltage across the determination circuit while the current is applied; determining that the discharge lamp to be determined is new if the measured voltage across the circuit is within the predetermined upper and lower voltage range; determining that the discharge lamp to be determined is used if the measured voltage across the circuit is outside the predetermined upper and lower voltage range; and then blowing the fuse by applying a current larger than the DC current.

8. A first DC current forward to the diode is applied to the determination circuit of the light source device according to claim 2 for a predetermined time, the voltage across the determination circuit is measured at least twice while the current is applied, the difference between the voltage across the circuit at the time of the first measurement and the voltage across the circuit at the time of the second measurement is compared with a predetermined upper and lower voltage range for determining whether the discharge lamp is genuine or not, if the difference in the voltage across the circuit is within the predetermined voltage range, it is determined that the discharge lamp to be judged is a genuine product, if the difference in the voltage across the circuit is outside the predetermined voltage range, it is determined that the discharge lamp to be judged is not a genuine product, and after determining whether the discharge lamp is genuine or not, a second DC current reverse to the diode is applied to the determination circuit, the voltage across the determination circuit is measured while the current is applied, if the measured voltage across the circuit is within the predetermined upper and lower voltage range, it is determined that the discharge lamp to be judged is new, if it is outside the predetermined upper and lower voltage range, it is determined that the discharge lamp to be judged is used, A method for determining whether a light source device short-circuits the diode by applying a third DC current and voltage in the reverse direction that is larger than the second DC current.

9. A first DC current in the reverse direction to the diode is applied to the determination circuit of the light source device according to claim 3 for a predetermined time, the voltage across the determination circuit is measured at least twice while the current is applied, the difference between the voltage across the circuit at the time of the first measurement and the voltage across the circuit at the time of the second measurement is compared with a predetermined upper and lower voltage range for determining whether the discharge lamp is genuine or not, if the difference in the voltage across the circuit is within the predetermined voltage range, it is determined that the discharge lamp to be judged is a genuine product, if the difference in the voltage across the circuit is outside the predetermined voltage range, it is determined that the discharge lamp to be judged is not a genuine product, and after determining whether the discharge lamp is genuine or not, a second DC current in the reverse direction to the diode is applied to the determination circuit, the voltage across the determination circuit is measured while the current is applied, if the measured voltage across the circuit is within the predetermined upper and lower voltage range, it is determined that the discharge lamp to be judged is new, if it is outside the predetermined upper and lower voltage range, it is determined that the discharge lamp to be judged is a used product, A method for determining whether a light source device short-circuits the diode by applying a third DC current and voltage in the reverse direction that is larger than the second DC current.

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