JP3225857B2 - Dielectric barrier discharge device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a discharge lamp used as an ultraviolet light source for photochemical reactions, for example, which forms excimer molecules by dielectric barrier discharge.
The present invention relates to a light source device including a so-called dielectric barrier discharge lamp using light emitted from the excimer molecule.

[0002]

2. Description of the Related Art As a technique related to the present invention, a dielectric barrier discharge lamp is disclosed in, for example, JP-A-2-735.
No. 3 includes a discharge vessel filled with a discharge gas for forming excimer molecules, and a dielectric barrier discharge (also known as an ozonizer discharge or a silent discharge. The revised edition of the Institute of Electrical Engineers, “Discharge Handbook,” June 2001. Resale 7th issue No. 26
(See page 3) to form excimer molecules and extract the light emitted from the excimer molecules.

The above-described dielectric barrier discharge lamp and the light source device including the same have various features not found in conventional low-pressure mercury discharge lamps and high-pressure arc discharge lamps, and thus have a wide variety of application possibilities. I have. Above all, with the increasing interest in environmental pollution in recent years, non-polluting material processing using photochemical reaction by ultraviolet rays is one of the most important applications.

First, the structure of a dielectric barrier discharge lamp according to the present invention will be briefly described with reference to FIG. The dielectric barrier discharge lamp (B) has electrodes (Ea) and (Eb) sandwiching a discharge plasma space (G).
In between, there is one or two dielectrics. FIG.
1 shows a dielectric barrier discharge lamp in which two dielectrics (D) are present. Incidentally, in FIG. 1, the lamp sealing glass (U) also serves as the dielectric (D). When lighting the dielectric barrier discharge lamp (B), the electrodes (E
a) In (Eb), for example, 10 kHz to 200 kHz,
A high-frequency AC voltage of 2 kV to 10 kVrms is applied. However, the discharge plasma space (G) and the electrode (Ea)
Because of the dielectric (D) interposed between (Eb), the electrode (Eb)
a) The current does not flow directly from (Eb) to the discharge plasma space (G), but the current flows due to the dielectric (D) acting as a capacitor. That is, on the surface of each dielectric (D) on the side of the discharge plasma space (G), a charge having the same sign as that of the surface on each of the electrodes (Ea) and (Eb) is induced by polarization of the dielectric, and the discharge plasma is discharged. Discharge occurs between the surfaces of the dielectric (D) facing each other across the space (G). In the portion where the discharge has occurred, the charge induced on the surface of the dielectric (D) on the side of the discharge plasma space (G) is immediately neutralized by the discharge, so that the discharge current lasts only for an extremely short time. Since little current flows along the surface of the dielectric (D) on the side of the discharge plasma space (G), the portion where the discharge has occurred once has the polarity of the AC voltage applied to the electrodes (Ea) and (Eb). No re-discharge until reversal. In addition, since the timing at which discharge occurs is not the same for each location of the dielectric (D), in the dielectric barrier discharge lamp, a large number of discharge paths (J1, J2,.
‥) is generated and disappeared non-uniformly, and the place where the discharge path (J1, J2, ‥‥) occurs may move with time. Incidentally, the electrodes (Ea) and (Eb)
If any one or both of the electrodes is a mesh electrode, the emitted light can be emitted from the lamp to the outside without being blocked by the electrode.

[0005] Matters related to the difference between the dielectric barrier discharge lamp and other discharge lamps in terms of the stability of discharge and light emission during operation will be described. Other discharge lamps include
Immediately after lighting, the amount of light emission is low or the discharge is not stable in many cases, and it takes a long time until the amount of light emission is stabilized. In addition, when the lamp is repeatedly turned on and off frequently, the life of the lamp is significantly shortened in many cases, and in some cases, an extremely high starting voltage is required for lighting in comparison with a steady state. In many cases, there are many problems related to lighting, such as the life of the lighting device being significantly shortened. Therefore, even if there is a period when the light emitted from the lamp is not effectively used,
It is used in such a way as to make it stand by in the lighting state.
Naturally, this still leads to unnecessary shortening of life, and it is also a waste of power, but the degree of life shortening is lower than frequent lighting and extinguishing. It is just ignored.

On the other hand, in the dielectric barrier discharge lamp, a stable discharge is obtained immediately after the start of lighting, and the amount of light emission corresponding to the discharge is generated inside the lamp. But basically, shortening the life is
It depends only on the pure lighting cumulative time. Therefore, in this application, the lamp can be simply turned off during the period when the light emitted from the lamp is not required, and there is a great advantage that unnecessary standby time in the lighting state does not shorten unnecessary life and waste power. is there.

Next, the situation where precise control of the light emission amount is required in the application of the dielectric barrier discharge lamp to ultraviolet light will be described. The effect of material treatment by ultraviolet light of the dielectric barrier discharge lamp is based on a very complicated and advanced photochemical reaction.
There must be no excess or deficiency in the irradiation energy density relative to the desired value. If the irradiation energy density is insufficient, it is obvious that this is a problem because the irradiation effect is low. Even when the irradiation energy density is excessive, for example, decomposition products due to irradiation ultraviolet rays may react again, causing unintended molecular synthesis to form a non-uniform impurity layer on the surface of the target processing material. . Therefore, there is a certain allowable range in the excess and deficiency of the irradiation energy density depending on the kind of material processing reaction to be performed, and an ideal dielectric barrier discharge device has an irradiation energy density, that is, a luminescence that can be satisfied. Precision control of the quantity is required.

Next, problems specific to the ultraviolet radiation lamp will be described. As described above, the dielectric barrier discharge lamp is stable immediately after lighting, unlike many other discharge lamps. However, such a lamp for emitting ultraviolet light has a special mechanism of variation in light emission amount regardless of whether it is a dielectric barrier discharge lamp or another lamp. Among the dielectric barrier discharge lamps, in particular, in a dielectric barrier discharge lamp using xenon as a discharge gas, the effect of such light emission amount fluctuation is large.

In general terms, in a light source device, there are roughly two types of fluctuations in the amount of light emitted from a lamp.
Is a phenomenon on a short time scale in which the amount of light emitted from the lamp varies with time when the lamp is started to be turned on from the off state.
It is a long time scale phenomenon that fluctuates towards the end of its life. The fluctuation in the second lamp light emission amount is basically such that the lamp light emission amount decreases as the end of life is approached.

The dielectric barrier discharge lamp using xenon as a discharge gas emits excimer light having a center wavelength of 172 nm, which is valuable as a few short-wavelength light sources in the vacuum ultraviolet region. Therefore,
As a factor of the characteristic variation, there is one caused by the lamp sealing glass.

Since the sealing glass (U) of this kind of dielectric barrier discharge lamp must be able to transmit vacuum ultraviolet light having a wavelength of 172 nm, high purity quartz glass is used. However, the absorption edge of quartz glass, that is, the shortest limit wavelength that can be transmitted is 170 nm.
Near the edge, the absorption edge is the purity and temperature of quartz glass,
It changes depending on the composition defect density and the like. In general, the lower the purity, the higher the temperature, and the higher the composition defect density, the more the absorption edge of the quartz glass moves to the longer wavelength side. Therefore, even in a lamp using high-purity quartz as the sealing glass, if the temperature of the lamp itself increases due to lighting, the transmittance of the sealing glass decreases. This reduces the amount of light emitted by the lamp, which corresponds to the first of the aforementioned variations.
In addition, the radiation from the dielectric barrier discharge lamp is high-energy ultraviolet photons, but if the cumulative lighting time is prolonged, the high-energy ultraviolet photons emitted by the lamp itself will increase the composition defect density of the sealing glass of the lamp itself. And eventually
The transmittance of the sealing glass will be reduced. This also reduces the amount of light emitted by the lamp, which corresponds to the second variation described above.

That is, as described above, even in a dielectric barrier discharge lamp having excellent stability immediately after lighting, these lamp light emission amount fluctuations exist as long as short-wavelength ultraviolet rays are emitted. Fluctuations in the first and second lamp light emission amounts due to these fluctuations in the transmittance of the lamp envelope glass may never occur in a light source device requiring precise control of the irradiation energy density, such as in the application of the material processing. It wasn't forgiving and improvements were needed.

Conventionally, in many lamps other than the dielectric barrier discharge lamps, regardless of whether they are for ultraviolet radiation or not, as described above, a long preliminary lighting period is provided from the start of lighting and the amount of light emission is increased. Has been used in such a manner that the light emitted from the lamp is not effectively used, and even if there is a period during which the emitted light from the lamp is not effectively used, the standby state is maintained in the lighting state.
Of the amount of light emitted from the lamp was relatively low. Naturally, if the same usage is performed in the dielectric barrier discharge lamp, the fluctuation of the first lamp light emission amount will be suppressed to a relatively low level. By doing so, there is no use of any features that can avoid unnecessary shortening of service life and waste of power due to standby in the lighting state. Therefore, the lamp emission amount feedback, that is, the lamp emission amount is measured using some kind of lamp emission amount measuring means,
It is necessary to perform feedback control so that this becomes an expected value.

However, such a feedback control corrects the fluctuation of the first lamp light emission amount, but does not correct the fluctuation of the second lamp light emission amount.
The reason is described below. As described above, high energy ultraviolet photons are emitted from the dielectric barrier discharge lamp, and the lamp emission amount measuring means is also deteriorated by the high energy ultraviolet photons. For example, when a silicon photodiode is used as a lamp light emission amount measuring means, a light receiving window made of quartz glass is commercially available, but this quartz window is deteriorated by high-energy ultraviolet rays and is protected by the window. The supposed silicon photodiode itself is also gradually destroyed by high-energy ultraviolet photons. Instead of directly detecting ultraviolet light with a photodiode, after converting ultraviolet light to longer wavelength light, for example, visible light with a phosphor or the like, the converted light is detected by a photodiode, thereby indirectly detecting the converted light. There is a method for detecting ultraviolet rays, but in this case, the wavelength conversion member such as a phosphor is deteriorated by the ultraviolet rays. Eventually, these deteriorations appear as a decrease in the sensitivity of the lamp emission amount measuring means. This phenomenon is an unavoidable problem in a short wavelength light source device such as the present dielectric barrier discharge device. When the lamp emission amount feedback is performed based on the lamp emission amount measuring means whose sensitivity has decreased, control is performed so that the lamp emission amount deviates from the expected value to detect the lamp emission amount smaller than the actual one. The problem that it is done arises.
By selecting a phosphor or the like with as little deterioration as possible, it is possible to prevent the decrease in the sensitivity of the lamp light emission amount measuring means from proceeding in a short time, so that the fluctuation of the first lamp light emission amount is corrected. it can. However, since the decrease in the sensitivity of the lamp light emission amount measuring means gradually progresses over a long period of time, the fluctuation of the second lamp light emission amount cannot be accurately corrected.

Since the second variation in the amount of emitted light of the lamp occurs gradually over a long period of time, the means for measuring the amount of emitted light of the lamp does not need to receive light over the entire lighting period of the lamp. By providing, for example, a shutter or the like before the means and opening the shutter or the like only when measuring the amount of lamp light emission, it is possible to correct the fluctuation of the second lamp light amount, It is possible to prevent the decrease in sensitivity described above. However, this makes it impossible to measure the amount of emitted light of the lamp during most of the lighting period of the lamp, so that the fluctuation of the amount of emitted light of the first lamp cannot be corrected. A method of correcting the fluctuation of the first lamp light emission amount by frequently repeating opening of the shutter or the like for a very short time may be considered. In this case, however, a mechanical operation of the shutter or the like is considered. A problem occurs with the life.

[0016]

An object of the present invention is to provide a dielectric barrier discharge lamp that emits short-wavelength ultraviolet light, in which the transmittance of the sealing glass is reduced due to a rise in the temperature of the lamp itself, or the lamp itself is reduced. Even when the transmittance of the sealing glass decreases due to the high-energy ultraviolet photons emitted by the lamp, the first time, when the lighting is started from the unlit state, the change in the short-time scale in which the lamp light emission amount changes with the lapse of time. A second object of the present invention is to provide a dielectric barrier discharge device capable of correcting both fluctuations in a long time scale in which the amount of light emitted by a lamp changes from the time when the lamp is new to the end of its life. .

[0017]

In order to solve this problem, a first aspect of the present invention is to provide a discharge space (G, G1) filled with a discharge gas for generating excimer molecules by dielectric barrier discharge. , G2,...), And a bipolar electrode (E) for inducing a discharge phenomenon in the discharge gas.
a, Ea1, Ea2, ‥‥) (Eb, Eb1, Eb2,
‥‥) and a dielectric barrier discharge lamp (B, B1, B2, ‥‥) having a structure in which a dielectric (D, D1, D2, ‥‥) is interposed between the discharge gas and the discharge gas.
And the electrodes (Ea, Ea) of the dielectric barrier discharge lamp.
a1, Ea2, ‥‥) (Eb, Eb1, Eb2, ‥‥)
And a power supply device (P) for applying an AC high voltage to the dielectric barrier discharge lamp (B, B1, B2,...). The power supply device (P) having a lamp light emission amount measuring means (F1) and a second lamp light emission amount measuring means (F2);
However, the error between the first lamp light emission amount measurement signal (f1) from the first lamp light emission amount measurement means (F1) and the lamp light emission target value signal (g1) indicating the target value of the lamp light emission amount is small. The dielectric barrier discharge lamp (B, B
1, B2,...), And performs feedback control of the input power to the first lamp emission amount measurement signal (f1).
By the second lamp light emission amount measurement signal (f2) from the second lamp light emission amount measurement means (F2), and the dielectric barrier discharge lamp (B, B1, B2,
Ii) means (S) for substantially preventing the emitted light from reaching the second lamp luminous intensity measuring means.

According to a second aspect of the present invention, there is provided the dielectric barrier discharge device according to the first aspect, wherein the second lamp light emission amount measuring means (F2) includes the dielectric barrier discharge lamp (B). , B1, B2,...) Are installed near a place where an irradiation target (W) to be irradiated with the radiation light from the dielectric barrier discharge lamp (B, B1, B1,
By moving the second lamp light emission amount measuring means (F2) to a place where the radiation light from B2, ‥‥) does not reach,
The dielectric barrier discharge lamp (B, B1, B2,...)
This is characterized in that the emitted light is substantially prevented from reaching the second lamp emission amount measuring means.

According to a third aspect of the present invention, there is provided the dielectric barrier discharge device according to the first aspect, wherein the dielectric barrier discharge lamps (B, B1, B2,...) The object to be irradiated (W) irradiated with light emitted from the discharge lamps (B, B1, B2,...) Has a structure separated by a light-transmissive irradiation window (T1). Of the dielectric barrier discharge lamp (B, B1, B2, B2) with respect to the irradiation window (T1).
‥‥), and in the path where the radiated light from the dielectric barrier discharge lamps (B, B1, B2, ‥‥) reaches the second lamp luminous intensity measuring means (F2), Body discharge lamp (B, B1, B2,...) And the dielectric barrier discharge lamp (B, B1, B2,.
‥) and means (S) for substantially preventing the radiated light from reaching the second lamp luminous energy measuring means, between the dielectric barrier discharge lamps (B, B1, B2, ‥‥) and the means (S). A light-transmitting window (T2) having deterioration characteristics with respect to emitted light that is substantially the same as the irradiation window (T1) is provided.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention of claim 1 will be described with reference to FIG. 2, which is a simplified drawing for showing the concept. One or more dielectric barrier discharge lamps (B, B1, B2,...) Are connected to the power supply device (P).

The power supply device (P) is an AC power supply line (1)
DC power supply unit consisting of a diode bridge (2) connected to the power supply, a smoothing capacitor (3), and mainly a FET
(14), diode (15), choke coil (1
6), a step-down type chopper power supply unit including a smoothing capacitor (4a, 4b) and a bias excitation preventing capacitor (5), a half-bridge type inverter unit mainly including two FETs (6a, 6b), a step-up transformer ( 13a).

The chopper power supply unit sends a chopper gate signal (18), which is a signal that repeats a high level and a low level, to an attached chopper gate drive circuit (17) to turn on and off the FET (14). Is repeated, the voltage generated in the smoothing capacitors (4a, 4b) can be changed by changing the ratio between the high level and the low level of the chopper gate signal (18), that is, the duty ratio. In the inverter section, the inverter gate signal generation circuit (8) operates by receiving the clock signal (11) from the oscillator (10) and operates the two F gates.
The inverter gate drive circuit (7) attached to each FET so that the ET (6a, 6b) alternately turns on and off alternately.
a, 7b). The FET (6
a, 6b) alternately turns on and off,
The secondary winding of the step-up transformer (13a) has
A high AC voltage largely determined by the turn ratio between the secondary winding and the secondary winding and the voltage of the smoothing capacitors (4a, 4b) can be applied to the lamps (B, B1, B2,...). It has become.

The clock signal (11) is, for example, 10
At this time, the secondary winding of the step-up transformer (13a) supplies an AC high voltage of 50 kHz to the lamps (B, B1, B2,...).

The first lamp light emission amount measuring means (F1) for supplying the first lamp light emission amount measurement signal (f1) comprises an ultraviolet ray sensor (26) and a variable gain amplifier (28), and the second lamp The second lamp light emission amount measuring means (F2) for supplying the light emission amount measurement signal (f2) includes an ultraviolet sensor (27) and an amplifier (30). The ultraviolet sensor (27) includes a lamp (B, B1, B2,...)
Means (S) for preventing the further radiation light from entering and canceling the prevention are provided. The variable gain amplifier (28) includes, for example, an operational amplifier (63), a capacitor (69), and a variable resistance element (88). The amplifier (30) includes, for example, an operational amplifier (64), a capacitor ( 70) and a resistor (76). The variable resistance element (88) may be any resistor as long as its resistance can be changed by an external signal.

The first lamp light emission amount measurement signal (f1)
And a lamp emission amount target value signal (g1) from the lamp emission amount target value signal generating means (34).
5), a capacitor (71), resistors (77), (78), etc., which are input to a lamp light emission error integration circuit (24). The comparator (22) includes a sawtooth wave oscillator (2
0) and a lamp light emission level signal (25) from the lamp light emission error integration circuit (24), and the chopper gate signal (18).
Is supplied from the comparator (22).

The frequency of the sawtooth signal (23) of the sawtooth oscillator (20) can be, for example, about 200 kHz, and the FET (14) of the chopper power supply operates at this frequency.

Here, the first lamp light emission amount measurement signal (f1) is a signal having a negative polarity, that is, a signal having a negative voltage having a larger absolute value as the lamp light emission amount is larger. If the signal (g1) is designed to be a signal of positive polarity, that is, a signal having a higher positive voltage as the target lamp light emission amount is larger, the (24) lamp light emission amount error integration circuit may be configured as follows. 1 is the lamp emission amount target value signal (g1).
If it is smaller, the voltage of the lamp emission level signal (25), which is the output, is reduced, and the first lamp emission measurement signal (f1) is changed to the lamp emission target value signal (g1).
If it is larger, it works to increase the voltage of the lamp light emission level signal (25). Also, the comparator (22)
If the sawtooth signal (23) from the sawtooth oscillator (20) is higher than the lamp emission level signal (25) from the lamp emission amount error integrating circuit (24), the level is high. A signal is output. At this time, the chopper gate drive circuit (17) turns on the FET (14).
If the sawtooth signal (23) is lower, a low-level signal is output, and if the chopper gate drive circuit (17) is designed to turn off the FET (14), The first lamp light emission amount measurement signal (f1)
Is smaller than the lamp light emission target based on the lamp light emission target value signal (g1), the on-duty of the FET (14) increases, and as a result, the smoothing capacitor (4
a, 4b) rises and the lamps (B, B1, B2,
The voltage applied to the lamp (B, B)
1, B2, ‥‥) increases, and
It works to increase the amount of light emitted by the lamp. Conversely, if the first lamp emission amount measurement signal (f1) is larger than the lamp emission amount target based on the lamp emission amount target value signal (g1), the on-duty of the FET (14) decreases. As a result, the voltage of the smoothing capacitors (4a, 4b) drops, and the voltage applied to the lamps (B, B1, B2,...) Drops. The input power drops, and thus acts to reduce the amount of lamp emission. Eventually, feedback stabilization control of the lamp light emission amount is performed, and the first lamp light emission amount measurement signal (f1) always follows the level of the lamp light emission amount target value signal (g1).

(24) Regarding the time constant of the response of the lamp light emission error integrating circuit, when the lamp light emission target value signal (g1) changes from 0 to the rated lamp light emission in a stepwise manner, 1 lamp emission amount measurement signal (f
The time until 1) roughly follows can be set to, for example, about 20 ms.

The first lamp emission amount measurement signal (f1)
And the second lamp light emission amount measurement signal (f2) are supplied to the operational amplifier (66), the capacitor (72), the resistors (79) and (8).
0) and the like, which is input to a sensitivity error integration circuit (31). First, the first lamp light emission amount measurement signal (f
1) is a signal of negative polarity, that is, a signal having a negative voltage having a larger absolute value as the amount of light emitted from the lamp is larger.
The second lamp light emission amount measurement signal (f2) has a positive polarity,
That is, assuming that the signal has a higher positive voltage as the lamp light emission amount is larger, the sensitivity error integration circuit (31)
When the absolute value of the voltage of the first lamp light emission amount measurement signal (f1) is lower than the voltage of the second lamp light emission amount measurement signal (f2), a gain correction signal which is an output signal thereof When the absolute value of the voltage of the first lamp light emission amount measurement signal (f1) is higher, the voltage of the gain adjustment signal (32) is reduced. The gain correction signal (32) is input to gain control means (29). The gain control means (29)
When the gain adjustment permission signal (33) is at a high level, the gain of the variable gain amplifier (28) increases as the level of the gain adjustment signal (32), which is the input, increases. When the gain adjustment permission signal (33) is at a low level, the function of increasing or decreasing the gain of the variable gain amplifier (28) is stopped.

In the dielectric barrier discharge device having the above-described structure, the ultraviolet ray sensor (27) is provided with lamps (B, B).
1, B2,...), The gain adjustment permission signal (33) may be set to a low level. In this case, as described above, the gain adjustment permission signal (33) is always set to the low level. Feedback stabilization control of the lamp light emission amount is performed such that the lamp light emission amount measurement signal (f1) follows the lamp light emission amount target value signal (g1). That is, in this state, the fluctuation of the first lamp light emission amount described in the problem to be solved by the invention is corrected.

Next, after canceling the blocking of the radiation light from the lamps (B, B1, B2,...) Into the ultraviolet sensor (27), the gain adjustment permission signal (3
When 3) is set to a high level, the above-mentioned sensitivity error integration circuit (31) operates to cause the first lamp light emission amount measurement signal (f1) and the second lamp light emission amount measurement signal (f).
The gain of the variable gain amplifier (28) is changed in a feedback manner so as to reduce the difference from 2), and finally, the voltage of the first lamp emission amount measurement signal (f1) becomes In this case, the voltage becomes equal to the voltage of the lamp light emission amount measurement signal (f2). Therefore, if the ultraviolet light sensor (2) of the first lamp light emission amount measuring means (F1) is used.
Even when the sensitivity is reduced in 6), the second lamp light emission amount measurement signal (f2) based on the ultraviolet sensor (27) that has not lowered the sensitivity of the second lamp light emission amount measurement means (F2). ), The sensitivity of the first lamp light emission amount measuring means (F1) is adjusted by adjusting the gain of the variable gain amplifier (28) so that the first lamp light emission amount measurement signal (f1) matches. Will be corrected.
That is, in this state, it is understood that the fluctuation of the second lamp light emission amount described in the problem to be solved by the invention is corrected.

The first lamp light emission amount measuring means (F1)
When the sensitivity adjustment is completed, the gain adjustment permission signal (3
3) is set to low level, and the variable gain amplifier (2)
8) After fixing the gain value of the ultraviolet sensor (2)
It is sufficient to prevent the radiation from the lamps (B, B1, B2,...) From being incident on 7), so that the ultraviolet sensor (27) is not deteriorated by the short-wavelength ultraviolet of the dielectric barrier discharge lamp. .

As apparent from the above description,
By using the invention of claim 1 of the present invention, the lamp emission amount feedback based on the first lamp emission amount measuring means (F1) is performed during the lighting of the dielectric barrier discharge lamp, so that the invention is to be solved. The first lamp light emission amount measuring means (F2), which is based on the second lamp light emission amount measurement means (F2), which does not cause the fluctuation of the first lamp light emission amount and which is protected from the decrease in sensitivity, described in the subject. Since the correction of F1) can be performed as needed, it is possible to realize an extremely stable dielectric barrier discharge device which does not cause a change in the second lamp emission amount described in the problem to be solved by the invention. It is.

The first lamp light emission amount measuring means (F1) and the second lamp light emission amount measuring means (F1)
The surface area of the lamp surface that can be monitored by 2), in other words, a three-dimensional object that can effectively reach the first and second lamp light emission amount measuring means (F1) and (F2). The larger the surface area of the lamp surface in the corner, the better. The reason is that, as described above, in the dielectric barrier discharge lamp, a large number of discharge paths (J1, J1
2, ‥‥) are generated and disappeared in a non-uniform manner, and the place where the discharge path (J1, J2, 発 生) occurs may move with time. If the surface area of the lamp surface within a solid angle within which the emitted light can effectively reach the light amount measuring means (F1) and the second lamp light emitting amount measuring means (F2) is too small, at a certain point in time, , A discharge path (J1, J
When (2, ‥‥) does not exist, at this time, the lamp light emission amount is measured to be small even though the entire lamp light emission amount is normal. Conversely, the discharge path ( This is because when a large number of J1, J2,... Exist, the amount of emitted light from the lamp is measured to be large, and the measurement itself may be unstable.
Therefore, for example, when the frequency of the AC voltage applied to the dielectric barrier discharge lamp is in the range of 10 kHz to 100 kHz, the first lamp light emission amount measuring means (F1) and the second lamp light emission amount described above are used. Measurement means (F
The surface area of the lamp surface within a solid angle within which the emitted light can effectively reach 2) is desirably 400 mm ² or more.

Further, the lamp surface within a solid angle within which the radiated light can effectively reach the first lamp luminous intensity measuring means (F1) and the radiant light can be effectively radiated to the second lamp luminous amount measuring means (F2). The larger the surface area of the common portion with the lamp surface within a solid angle that can be reached, the better. The reason is that if the surface area of this common portion is too small, the above-mentioned first lamp light emission amount measuring means (F) is not uniform due to the aforementioned uneven distribution of the discharge paths (J1, J2, ‥‥).
This is because the ratio between the measured value of the lamp light emission amount of 1) and the measured value of the lamp light emission amount of the second lamp light amount measuring means (F2) may become unstable, and the correction operation may become unstable. . Therefore, for example, the frequency of the AC voltage applied to the dielectric barrier discharge lamp is 10 kHz to 100 kHz.
In the range described above, the lamp surface within a solid angle within which the emitted light can effectively reach the first lamp light emission amount measuring means (F1) and the second lamp light emission amount measurement means (F2) The surface area of the common portion with the lamp surface within a solid angle where the emitted light can effectively reach is within a solid angle where the emitted light can effectively reach the first lamp emission amount measuring means (F1). The larger of the surface area of the lamp surface and the surface area of the lamp surface within a solid angle within which the radiated light can effectively reach the second lamp luminous energy measuring means (F2).
% Is desirable.

It should be noted that even when the gain adjustment permission signal (33) is set to the high level and the gain of the variable gain amplifier (28) is feedback-controlled, the first lamp light emission amount measurement signal (f1) is not changed. The feedback control of the lamp light emission amount following the lamp light emission amount target value signal (g1) functions. In order to avoid the so-called contention of the feedback loop, the time constant of the response of the sensitivity error integration circuit (31) is set as described above. (24) It is desirable that the time constant of the response of the lamp light emission amount error integrating circuit be sufficiently larger, for example, about 10 times.

As means for preventing light emitted from the lamps (B, B1, B2,...) From being incident on the ultraviolet sensor (27) and for releasing the blocking, a mechanical shutter is used. Is the easiest. As a method of driving the shutter, a solenoid can be used.

Although not described above because it is not an essential matter, when the lamp is turned off, the inverter gate signal generating circuit (8) includes the two FETs.
(6a, 6b) are both controlled to be off,
The lamp light emission target value signal generating means (34)
Should be controlled so as to output the corresponding lamp emission amount target value signal (g1) when the lamp does not emit light.

Next, the second embodiment of the present invention will be described with reference to FIGS. 3A and 3B which are simplified drawings for showing the concept. FIG. 3a shows that the second lamp light emission amount measuring means or the light receiving portion (35) for supplying the second lamp light emission amount measurement signal (f2) is shielded by the light shielding means (36). , B2, ‥‥)
This shows a state where the radiated light is in a position where it is blocked. In this state, the radiation light from the dielectric barrier discharge lamp (B, B1, B2,.
The dielectric barrier discharge lamps (B, B1, B
This corresponds to a state in which the emitted light from 2, 2) is substantially prevented from reaching the second lamp emission amount measuring means.
FIG. 3a shows the dielectric barrier discharge lamp (B,
Illustrated is an irradiation target (W) irradiated with light emitted from B1, B2,...).

On the other hand, FIG. 3B shows that the second lamp light emission amount measuring means or its light receiving section (35) is controlled by the light shielding means (36) to use the dielectric barrier discharge lamps (B, B1, B2,...).
FIG. 3A shows a state in which the object to be irradiated (W) has moved from the position where the emitted light is blocked and is near the position where the irradiation target (W) was present in FIG. In this state, the lamp (B, B) is connected to the ultraviolet sensor (27).
1, B2,...) Correspond to a state in which the blocking of the incident light from the light is released.

The first lamp light emission amount measuring means,
The power supply device and the like are installed in the same manner as in FIG. 2 and are not shown in FIGS. 3A and 3B.

It is clear that the second aspect of the present invention has the same advantages as the first aspect of the invention because of the correspondence between the configurations of FIGS. 3a and 3b described above and the first aspect of the invention. The second aspect of the present invention has another advantage not described in the description of the first aspect of the present invention. The other advantage will be described below.

In a light source device for material processing using short-wavelength ultraviolet light such as a dielectric barrier discharge device, a lamp (B,
B1, B2,...) Are housed in a container having an irradiation window (T1) made of quartz glass, and ultraviolet rays irradiating the object to be irradiated (W) pass out of the container through the irradiation window (T1). The structure of taking out is common. The irradiation window (T1)
Are described in FIGS. 3a and 3b.

For example, a dielectric barrier discharge lamp using xenon as a discharge gas as described in the prior art,
Short-wave ultraviolet light having a wavelength of 172 nm is emitted. Since ultraviolet light having this wavelength is absorbed by oxygen in the air, the thickness of the air layer between the lamp and the object to be irradiated must be minimized. The purpose of using the irradiation window (T1) is to fill the inside of the container for storing the lamps (B, B1, B2,. Then, the irradiation window (T1)
Irradiating light from the lamps (B, B1, B2,...) Efficiently reaches the illuminated object (W) only by the thin air layer between the object and the illuminated object (W). That's why.

However, as described in the prior art, short-wavelength ultraviolet light deteriorates quartz glass and lowers its transmittance. If the second lamp emission amount measuring means is installed inside the irradiation window (T1), the ultraviolet rays from the lamps (B, B1, B2,...)
Since the light does not pass through the irradiation window (T1) and enters the second lamp light emission amount measuring means, the second lamp light emission amount measurement signal does not reflect the decrease in the transmittance of the irradiation window (T1). Therefore, in this case, the amount of decrease in the amount of light emitted from the lamp due to the decrease in the transmittance of the irradiation window (T1) is not corrected.

In the case of the structure of the second aspect of the present invention, the light receiving section (35) of the second lamp light emission amount measuring means is located at substantially the same position as the object to be irradiated (W), that is, the irradiation window (T1).
And the second lamp emission amount measurement signal includes:
Since the transmittance reduction of the irradiation window (T1) is reflected,
If a decrease in the amount of lamp light emission caused by a decrease in the transmittance of the irradiation window (T1) occurs, the dielectric barrier discharge device having the configuration of the first aspect of the present invention includes the decrease in the amount of lamp light emission. The sensitivity of the first lamp light emission amount measuring means (F1) is corrected by the second lamp light emission amount measurement signal. As a result, the lamp light emission amount decrease caused by the transmittance decrease of the irradiation window (T1) is included. It can be seen that it is corrected.

As described above, the provision of the second lamp light-emission amount measuring means light receiving section (35) outside the irradiation window (T1) has a great advantage. During the sensitivity correction operation of the light emission amount measuring means (F1), the second
The position where the light emission amount measuring means light receiving section (35) of the lamp should be set is originally a dielectric barrier discharge lamp (B, B1,
This position is the same as the position where the irradiation target (W) to be irradiated with the radiation light from B2,...) Is to be installed, and therefore, the two mechanically interfere with each other. Interference with the object to be irradiated is a particularly serious problem when the dielectric barrier discharge device is to be configured as an automatic machine in which the object to be irradiated is supplied by a robot transport device or the like. An excellent feature of the configuration of the present invention according to claim 2 is that the first
At times other than those required for the sensitivity correction operation of the lamp light emission amount measuring means (F1), the second lamp light emission amount measuring means light receiving section (35) moves from the space where the irradiation target (W) can exist to The problem of mechanical interference with the object to be irradiated (W) can be avoided merely by adopting a structure in which the light shielding means (36) moves to a certain position and leaves, and the second lamp light emission amount measuring means light receiving unit In order to prevent the ultraviolet sensor of (35) from being deteriorated by the short wavelength ultraviolet light of the dielectric barrier discharge lamp, the dielectric barrier discharge lamp (B, B1,
B2,...) Can substantially both prevent the emitted light from reaching the second lamp emission amount measuring means.

As described above, according to the second aspect of the present invention, even a dielectric barrier discharge device that irradiates an object to be irradiated (W) with irradiation light through an irradiation window (T1). A second lamp light emission amount measuring means (F2) can be installed to correct the deterioration including the irradiation window (T1), and at this time, the distance between the irradiation target (W) and the irradiation object (W) can be improved. The advantage that no mechanical interference occurs is obtained, and the basic functions are the same as those of the first aspect.
Since the lamp emission amount feedback based on the first lamp emission amount measuring means (F1) is performed during lighting of the dielectric barrier discharge lamp, which is an advantage of the present invention, the second aspect described in the problem to be solved by the invention. The first lamp light emission amount measurement means (F1) needs to be corrected based on the second lamp light emission amount measurement means (F2) which is not changed in the light emission amount of the first lamp and which is protected from a decrease in sensitivity. Since the invention can be implemented according to the problem to be solved by the invention,
By completely inheriting the advantage that the second lamp emission amount does not vary, it is possible to realize an extremely stable dielectric barrier discharge device.

The distance between the light receiving surface of the second lamp light emitting amount measuring means light receiving section (35) and the irradiation window (T1) during the sensitivity correcting operation of the first lamp light emitting amount measuring means is as follows. It is desirable that the distance between the irradiation window (T1) and the irradiation surface of the irradiation target object (W) when the irradiation target object is irradiated with ultraviolet rays be as equal as possible. If this distance is not the same, if the distance is not the same, the light receiving surface of the second lamp light emission amount measuring means light receiving unit (35) or the light receiving surface of the light receiving object (W) and the light emitting window ( T
The thickness of the air layer between 1) will not be the same,
In the air layer, ozone molecules are generated from oxygen molecules by ultraviolet rays, and the transmittance of the ultraviolet rays is different between the oxygen molecules and the ozone molecules. This is because the conditions are not the same when irradiating the object with ultraviolet light, and there is a possibility that correct correction cannot be performed. For example, in the case of a dielectric barrier discharge device in which the distance between the irradiation surface of the irradiation object (W) and the irradiation window (T1) is in the range of 3 to 10 mm, this distance and the second lamp emission are used. The light receiving surface of the light receiving section of the quantity measuring means and the irradiation window (T1)
Should be matched within an error range of ± 50%.

It should be added that the invention of claim 2 is still effective in a dielectric barrier discharge device without an irradiation window. If there is no irradiation window, the distance between the dielectric barrier discharge lamp (B, B1, B2,...) And the object to be irradiated (W) is generally larger than when there is an irradiation window, and therefore, It is considered that the above-mentioned absorption of ultraviolet rays by oxygen molecules and generation of ozone molecules from oxygen molecules by ultraviolet rays are also large. In general, the efficiency of ultraviolet irradiation on the irradiation target (W) is not good, and the efficiency is low. ,
Lamp (B, B1, B2, ‥‥) and irradiation target (W)
And the air flow speed in the space between the air conditioner and the exhaust conditions change more sensitively. The sensitivity of the first lamp light emission amount measuring means and the light receiving surface of the second lamp light emission amount measuring means light receiving portion (35) and the lamps (B, B1, B1,
B2, ‥‥) and the distance between the irradiation surface of the irradiation object (W) and the lamp (B, B1, B2, ‥‥) when the irradiation object is irradiated with ultraviolet light. The effect of the invention of claim 2 in which the distance and the distance are made as equal as possible is great. For example, the distance between the irradiation surface of the irradiation target (W) and the lamps (B, B1, B2,...) Is 20 to 50.
In the case of the dielectric barrier discharge device in the range of mm, this distance and the distance between the light receiving surface of the second lamp light emission amount measuring means light receiving section and the lamp (B, B1, B2,...) , ±
It should be matched within a 10% error range.

Next, regarding the invention of claim 3 of the present invention, first, it is described that the invention of claim 2 may not be applied, and then a simplified drawing for showing the concept of the invention of claim 3 is described. This will be described with reference to FIG.

First, regarding a dielectric barrier discharge device that irradiates an object to be irradiated with radiation light through an irradiation window,
When the second lamp emission amount measuring means is installed inside the irradiation window, it is possible to avoid a problem that the lamp emission amount decrease due to the decrease in the transmittance of the irradiation window is not corrected. It has been stated that the invention of claim 2 is useful. The invention of claim 2 has described that the problem that the second lamp light emission amount measuring means light receiving section mechanically interferes with the irradiation target object can be avoided. However, it may not be possible to move the light-receiving section of the second lamp light emission amount measuring means to the position before the irradiation window due to mechanical dimensions, and the light-receiving section may be placed on a special irradiation target such as a belt conveyor. If the object to be irradiated or the object to be irradiated in the form of a continuous roll flows in front of the irradiation window of the present dielectric barrier discharge device, the irradiation window may be adjusted in order to correct the sensitivity of the first lamp emission amount measuring means. In some cases, it may not be possible to remove a belt conveyor or a continuous roll sheet-shaped object to be irradiated from before. Such a problem that the second light emitting amount measuring means light receiving section cannot be installed at all outside the irradiation window can be solved by the invention of claim 3 shown in FIG.

In FIG. 4, there is provided an irradiation window (T1) made of an ultraviolet transmitting material such as quartz glass for extracting ultraviolet rays from the dielectric barrier discharge lamps (B, B1, B2,...) To the outside. When the object to be irradiated (W) is irradiated with ultraviolet rays, the irradiation is performed through this. A second lamp light emission amount measuring means (F2) for supplying a second lamp light emission amount measurement signal (f2) is provided to the dielectric barrier discharge lamp (B, B1, B2,...) With respect to the irradiation window (T1). Installed on the side of i). The lamp (B, B1, B2,...) Is provided in the second lamp emission amount measuring means (F2) or its light receiving section (35).
A means for preventing the emission of the light emitted from ‥) and canceling the prevention, for example, a shutter (S) is provided.

The dielectric barrier discharge lamp (B,
B1, B2,...) And the shutter (S),
The dielectric barrier discharge lamp (B, B1, B2,...)
A light-transmissive window (T2) is inserted in which the deterioration characteristic with respect to the emitted light, that is, the relationship between the cumulative amount of ultraviolet irradiation and the decrease in transmittance is substantially the same as the irradiation window (T1). As the window (T2) that satisfies such conditions, a window made of the same material having the same thickness as the irradiation window (T1) can be used. Most simply, the irradiation window (T1)
May be cut away. The important point here is that
Regardless of whether or not the shutter (S) is blocking the incidence of ultraviolet light on the second lamp light emission amount measuring means (F2), the shutter (S) is turned on while the lamps (B, B1, B2,. Is irradiated with ultraviolet rays to the window (T2). At this point, the conditions for the irradiation of ultraviolet rays are exactly the same for the window (T2) and the irradiation window (T1). Note that the first lamp light emission amount measuring means, the power supply device, and the like are installed in the same manner as in FIG. 2 and are not shown in FIG.

According to the third aspect of the present invention, the second lamp light emission amount measurement signal obtained by the second lamp light emission amount measurement means (F2) is the second lamp light emission amount measurement signal. It is almost always the same as the second lamp emission amount measurement signal obtained when the means is installed outside the irradiation window (T1). The reason is that, as described above, the condition of the irradiation of the ultraviolet rays and the deterioration characteristics due to the ultraviolet rays are different from those of the window (T2).
And the irradiation window (T1). Therefore, the invention of claim 3 provides the advantage of the invention of claim 2 in the present dielectric barrier discharge device having an irradiation window, that is, by correcting the sensitivity of the first lamp light emission amount measuring means (F1). The outside of the irradiation window, which has an advantage of being able to correct including a decrease in the amount of lamp light emission caused by a decrease in the transmittance of the irradiation window (T1), and in which the above-described invention of claim 2 cannot be avoided. In addition, it can be seen that there is a great advantage that the problem when the second lamp light emission amount measuring means light receiving unit cannot be installed at all can be completely avoided.

[0056]

FIG. 5 shows a simplified example of an embodiment of the present invention. The power supply device (P) includes a diode bridge (2) connected to the AC power supply line (1), a smoothing capacitor (4a, 4b), and a bias excitation preventing capacitor (5).
DC power supply unit and mainly two FETs (6
a, 6b), and a boosting unit including a boosting transformer (13b). In FIG. 2 showing an example of the invention of claim 1, a chopper is included to increase or decrease the lamp power.
Instead of a chopper, a series resonance circuit including a resonance coil (37) and a resonance capacitor (38) is added to the secondary side of the step-up transformer (13b), and a resonance phenomenon occurs between both terminals of the resonance capacitor (38). It is assumed that a method is used in which a high voltage, that is, a voltage applied to the lamps (B, B1, B2,...) Is changed according to the frequency of the inverter to change the power supplied to the lamp. . In the case of this example, it is assumed that the operation is performed in a region where the frequency of the inverter is higher than the resonance frequency. At this time, the power supplied to the lamp increases as the frequency of the inverter decreases from a high value and approaches the resonance frequency. The resonance frequency is determined by the capacitance of the lamp (B, B1, B2,...), The capacitance of the resonance capacitor (38), and the inductance of the resonance coil (37).

In FIG. 2, a lamp light emission amount error integrating circuit (2) to which the first lamp light emission amount measurement signal (f1) is input is shown.
According to 4), a circuit for increasing or decreasing the lamp power and directly realizing the lamp emission amount feedback was assumed.
In FIG. 5, a lamp power feedback circuit configured based on the lamp current is configured, and as a feedback loop larger than this, a lamp light emission amount feedback using the first lamp light emission amount measurement signal (f1) as input is achieved. System. The reason for configuring the feedback circuit based on the lamp current is that the lamp current is electrically correlated with the lamp power, can be easily measured, and is a stable amount.

The lamp power signal (43) representing the magnitude of the lamp power is supplied to a current transformer (40) for detecting the current of the lamps (B, B1, B2,...) And an AC signal (41). ) To rectify and direct-current and amplify, an operational amplifier (67), resistors (81), (82), (83),
It is generated by a rectifier amplifier (42) composed of diodes (89) and (90). The lamp power signal (4
3) and the lamp power target value signal (44) are supplied to the operational amplifier (91), the capacitor (73), the resistors (84) and (8).
5) Lamp power error integration circuit (45) composed of
, Whereby the lamp power level signal (46)
Is generated. The lamp power target value signal (44) is
Data generated by the D / A converter (53),
That is, the setting of the lamp power target value data is performed by the computer circuit (59) writing to the register (60).

The variable frequency clock signal (12) from the voltage controlled oscillator (VCO) (39) is input to the inverter gate signal generation circuit (8). The lamp power level signal (46) is input to the voltage controlled oscillator (39), and the lamp power level signal (4
The frequency of the inverter is changed by changing the voltage of 6). In this case, the lower the voltage of the lamp power level signal (46) input to the voltage-controlled oscillator (39), the lower the oscillation frequency of the voltage-controlled oscillator (39) and the more the power supplied to the lamp. Shall be. The inverter gate signal generation circuit (8)
Is a state in which both operations of the inverter gate drive circuits (7a, 7b) are stopped, that is, a state in which the inverter is stopped, and a state in which pulses are alternately transmitted to the inverter gate drive circuits (7a, 7b) in accordance with the clock signal (12). That is, it has an inverter operation control signal (9) for controlling any one of the inverter operation states. Through this signal, the computer circuit (59) writes a data bit to the register (61) to thereby control the inverter. Operation and stop can be controlled.

In such a configuration, for example, the lamp power signal (43) is a signal having a negative polarity, that is, a signal having a negative voltage having a larger absolute value as the lamp power increases, and the lamp power target value signal (44). Is a positive signal, that is, a signal having a higher positive voltage as the target lamp power is larger, in the inverter operating state, the lamp power error integration circuit (45) sets the actual lamp power to be higher than the lamp power target. When it is smaller, the lamp power level signal (4
6), the oscillation frequency of the voltage-controlled oscillator (39) decreases, the voltage applied to the lamp increases, and the power supplied to the lamp increases. Conversely, when the actual lamp power is greater than the lamp power target, the voltage of the lamp power level signal (46) is increased, so that the oscillation frequency of the voltage controlled oscillator (39) is increased and the voltage applied to the lamp is decreased. Thus, the power supplied to the lamp works to decrease.

That is, it is understood that a lamp power feedback loop is formed, and the lamp power always follows the lamp power target value signal (44) set by the computer circuit (59).

On the other hand, the first lamp light emission amount measurement signal (1
First lamp emission amount measuring means (F1) for generating 1)
Is a photodiode (49), a phosphor (47), an operational amplifier (68), a capacitor (74), a resistor (86)
The second lamp light emission amount measuring means (F2) configured to generate the second lamp light emission amount measurement signal (12) includes a photodiode (50), a phosphor (48), an operational amplifier (92), and a capacitor. (75) and a resistor (87). The phosphor (48) and the lamp (B, B1, B
2), a shutter (S) is installed, and between the shutter (S) and the lamps (B, B1, B2, ‥‥), an object to be irradiated is irradiated with ultraviolet rays. A window (2) of the same material is set as the irradiation window (T1). The shutter (S) has a shutter control signal (52) for driving by a solenoid or the like via a shutter drive circuit (51), and the computer circuit (59) receives the shutter control signal via this signal. Data bits are stored in the register (6
By writing in 1), the opening and closing of the shutter (S) can be controlled.

The first lamp light emission amount measurement signal (f1)
And the second lamp light emission amount measurement signal (f2), one of them is selected by a switch circuit (56) by a switch control signal (58) via a switch drive circuit (57), and AD converted. The digital data is converted into digital data by the device (54) and can be read by the computer circuit (59) via the bus gate (62). However, the AD converter (5)
The AD conversion operation of 4) is performed by the computer circuit (59).
Is started by sending an AD conversion start pulse signal (55) to the AD converter (54), and the signal selection by the switch circuit (56) is performed by the computer circuit (59). It is assumed that selection can be controlled by writing bits to the register (61). In addition, as the switch circuit (56),
The one which applied the analog switch can be used.

The operation of the above-described dielectric barrier discharge apparatus having the configuration of the embodiment of the present invention shown in FIG. 5 will be described below. The computer circuit (59) prevents the ultraviolet rays from the lamps (B, B1, B2,...) From being incident on the second lamp emission amount measuring means (F2) prior to starting the lighting of the lamp. The shutter (S) is closed via the register (61), and lamp power target value data corresponding to the lowest lamp power is written in the register (60). ) To output an inverter operation control signal (9) to start the operation of the inverter.

Thus, the inverter gate signal generating circuit (8) operates according to the clock signal (12) from the voltage controlled oscillator (39) to drive the inverter gate driving circuit (7a, 7a).
7b) to send pulses alternately to ramps (B, B1, B
The application of the AC voltage to (2) is started. However,
At this time, since the lamp power target value data corresponding to the state where the lamp power is lowest is written in the register (60), the lamp power level signal (46)
Is in the highest voltage state of its transition, thus
The voltage controlled oscillator (39) outputs the highest frequency of the oscillation frequency change range, and outputs the ramps (B, B1, B
The AC voltage applied to (2) is low, and may be such that the discharge is not started.

After starting the operation of the inverter, the lamp power error integration circuit (45) and the like are formed by writing the lamp power target value data Px substantially corresponding to the target lamp power to the register (60). The above-described lamp power feedback loop operates, and the lamp power level signal (46) decreases. In response to this, the voltage-controlled oscillator (39) decreases its oscillation frequency, so that the voltage applied to the lamp increases. And the lamp (B, B1, B
2,...) Start lighting, and thereafter the lamp power quickly converges to a value corresponding to the lamp power target value data written in the register (60).

The computer circuit (59) can read the first lamp light emission amount measurement signal (f1) and write the lamp power target value data to the register (60). The lamp light emission amount feedback control can be performed by software so that the lamp light emission amount measurement signal (f1) becomes a target value.
As the lamp emission amount feedback is actually performed,
It is easy to operate the computer circuit (59). For example, a program according to the following procedure is
This can be achieved by executing at appropriate time intervals, for example, every second. 1. The switch circuit (56) is selected via the register (61) so that the value of the first lamp light emission amount measurement signal (f1) is input to the AD converter (54). 2. The AD conversion start pulse signal (55) is
Transmit to the converter (54). 3. The digital data Fx corresponding to the value of the first lamp light emission amount measurement signal (f1) is read through the bus gate (62). 4. A product Kx.Fx of a positive coefficient Kx held in the computer circuit (59) and the data Fx is calculated. 5. The lamp light emission amount target value data Gx held in the computer circuit (59) and the product value Kx · F
Calculate the difference Gx−Kx · Fx from x. 6. Using the value Px of the lamp power target value data recently written in the register (60) and the positive coefficient M held inside the computer circuit (59),
Calculate the value Px + M · (Gx−Kx · Fx) and use this value as the new value of Px. 7. The new value of Px is written to the register (60) as new lamp power target value data.

The reason that the lamp emission amount feedback is achieved by the above procedure is that when the value (Gx-Kx.Fx) is positive, the value corresponding to the magnitude of the first lamp emission amount measurement signal (f1) Since it means that Kx.Fx is less than the lamp light emission amount target value data Gx, Px is calculated as Px + M
Updating to (Gx−Kx · Fx) increases the value of the lamp power target value data, and conversely, the value Gx−Kx
When Fx is negative, the value of the lamp power target value data is reduced, and in any case, the value Gx−
This is because Kx · Fx is changed to be zero.

If the value of the coefficient M is too large, the state where the value of Kx · Fx is too large and too small is repeated at every update.
Since the time required for the value of Kx · Fx to substantially coincide with the value of Gx becomes longer, the value of M is determined in light of the response speed of the first lamp light emission amount measuring means (F1) and the update cycle of Px. It is better to experimentally determine an appropriate value.

Next, the second lamp light emission amount measurement signal (f) from the second lamp light emission amount measurement means (F2).
The first lamp light emission amount measuring means (F1) using 2)
Will be described. Prior to the start of the correction operation, the computer circuit (59) turns on the lamps (B, B1, B2,...) And performs the lamp emission amount feedback control in accordance with the above-described operation.
At this time, for example, by executing a program according to the following series of procedures, the first lamp light emission amount measuring means (F1) can be corrected. 8. The shutter (S) through the register (61) so that the ultraviolet rays from the lamps (B, B1, B2,...) Enter the second lamp light emission amount measuring means (F2).
open. 9. The switch circuit (56) is selected via the register (61) so that the value of the second lamp light emission amount measurement signal (f2) is input to the AD converter (54). 10. The AD conversion start pulse signal (55) is
Transmit to the converter (54). 11. The digital data Hx corresponding to the value of the second lamp light emission amount measurement signal (f2) is read through the bus gate (62). 12. The shutter (S) through the register (61) so that ultraviolet rays from the lamps (B, B1, B,...) Do not enter the second lamp emission amount measuring means (F2).
Close. 13. Using the data Hx and the digital data Fx corresponding to the value of the first lamp light emission amount measurement signal (f1) read via the bus gate (6) in the procedure 3 recently, the value Kx = Hx / Fx, and this value is referred to in the procedure 4 as the positive coefficient K
Let x be the new value.

The reason that the correction of the sensitivity deterioration of the first lamp light emission amount measuring means (F1) is achieved by the above procedure is that the data Hx and the data F of the procedure 13 are used.
x corresponds to the second lamp light emission amount measurement signal (f2) and the first lamp light emission amount measurement signal (f1) for the lamp light emission amount at substantially the same time, and the procedure 1
By using the value of Kx calculated in step 3, the product value Kx · Fx calculated from the data Fx in the procedure 4
Means that the second lamp emission amount measuring means (F
2) which is approximately equal to the measured value Hx that would be measured by the second lamp emission amount measuring means (F2).
This is because the protection of the shutter (S) does not cause sensitivity deterioration.

Note that the first lamp light emission amount measuring means (F2) is used by the second lamp light emission amount measuring means (F2).
In order to perform the correction operation of 1), the activation of the execution of the program by the series of procedures is performed by an operator,
Alternatively, an external device may issue the command to the computer circuit (59). Alternatively, the computer circuit (59) may be programmed so as to start automatically when the first lamp is turned on after the power is supplied to the dielectric barrier discharge device.
Alternatively, a variable is provided in the computer circuit (59) for counting and storing the accumulated time of the lamp lighting time, and the computer automatically starts up when the lamp is turned on every time the variable increases by a specified value. The circuit (59) may be programmed.

In the configuration of FIG. 2, the lamp emission target value signal (g1) is present as a single analog signal, but the corresponding configuration in the configuration of FIG.
This is the lamp light emission amount target value data Fx held in the computer circuit (59). The difference between the two is merely the difference between implementing the lamp emission amount feedback loop of the dielectric barrier discharge device by hardware in an electric circuit or by software in a computer circuit. They are exactly equivalent in concept.

With the configuration and operation of the dielectric barrier discharge device of the present embodiment described above, the excellent features exhibited by the dielectric barrier discharge device of the present embodiment will be summarized below. Since the first lamp light emission amount measuring means (F1) frequently performs the lamp light emission amount feedback, as described in the description of the first aspect of the present invention, when the lighting is started from the light-off state described above. In addition, a change in the amount of light emitted on a short time scale in which the amount of light emitted from the lamp changes over time due to a decrease in the transmittance of the sealing glass due to an increase in the temperature of the lamp itself is corrected. By installing a shutter (S) between the phosphor (48) and the lamps (B, B1, B2,...), The phosphor (48) hardly deteriorates and the shutter (S) And lamp (B, B
1, B2,...), A window (T2) of the same material as the irradiation window (T1) for irradiating the object to be irradiated with ultraviolet rays is provided. 2. The sensitivity of the first lamp light emission amount measuring means (F1) is corrected by the second lamp light emission amount measuring means (F2) capable of measuring the lamp light emission amount reflecting the decrease in transmittance of the light. As described in the description of the invention, the high-energy ultraviolet photons emitted from the lamp itself cause a decrease in the transmittance of the sealing glass as described above, so that the lamp emits light from the time when the lamp is new to the end of its life. The amount of change, the variation of the lamp emission on a long time scale,
A decrease in the amount of light emitted from the lamp due to a decrease in the transmittance of the irradiation window (T1) is corrected together.

The following configuration is possible in addition to the above description. 1. For example, a switching inverter may be replaced with another type of inverter, for example, a single transistor.
What is called a full bridge system consisting of four transistors. 2. In order to cope with the deterioration of the second lamp light emission amount measuring means, a lamp light emission amount measurement means with a lower frequency of ultraviolet irradiation is provided, and through this lamp light emission amount measurement,
The second lamp light emission amount measuring means can be corrected. The above items 1 and 2 are items that the designer arbitrarily implements within the scope of the present invention.

Of course, the circuit configuration shown in FIG.
This is an example in which only the main elements are described, and in the case of actual application, it should be changed appropriately according to the characteristics of the components used, differences in polarity, etc., and peripheral elements should be added as necessary Things.

[0077]

According to the first aspect of the present invention,
It has a first lamp light emission amount measuring means (F1) and a second lamp light emission amount measuring means (F2) for detecting the light emission amount of the dielectric barrier discharge lamp, and the first lamp light emission amount measuring means (F).
The input power to the dielectric barrier discharge lamps (B, B1, B2,...) Is feedback-controlled by the signal (f1) from 1), and the first lamp emission amount measurement signal (f1) is converted to the second lamp. Since there are means for regenerating by means of the signal (f2) from the light emission measurement signal (F2) and means for substantially preventing the light emitted from the dielectric barrier discharge lamp from reaching the second lamp light emission measurement means. During the lighting of the dielectric barrier discharge lamp, the lamp emission amount feedback based on the first lamp emission amount measuring means (F1) was performed, and the lighting was started from the fluctuation of the first lamp emission amount, that is, the lamp off state. Sometimes, control can be performed to satisfactorily correct fluctuations in a short time scale in which the amount of lamp light emission changes with time. In addition, since the first lamp light emission amount measuring means (F1) can be rehabilitated as needed based on the second lamp light emission amount measuring means (F2) protected from the sensitivity drop, the second lamp It is possible to provide an extremely stable dielectric barrier discharge device capable of satisfactorily correcting fluctuations in light emission amount, that is, fluctuations in a long time scale in which the lamp light emission amount changes from the time when the lamp is new to the end of its life. it can.

In the invention described in claim 2 of the present invention, the object to be irradiated (W) to which the second lamp light emission amount measuring means (F2) is irradiated with light emitted from the dielectric barrier discharge lamp is provided. The radiation light from the dielectric barrier discharge lamp is roughly moved by moving the second lamp light emission amount measuring means (F2) to a place which is installed near the place and where the radiation light from the dielectric barrier discharge lamp does not reach. In the case where the radiation light from the dielectric barrier discharge lamp is radiated to the irradiation target (W) through the irradiation window (T1), it is possible to prevent the second radiation including the deterioration occurring in the irradiation window (T1). The amount of lamp light emission can be controlled.

In the invention described in claim 3 of the present invention, the dielectric barrier discharge lamp and the object (W) to be irradiated with the light emitted from the dielectric barrier discharge lamp are light-transmitting transmission windows. (T1), wherein the second lamp luminous intensity measuring means (2) is provided on the dielectric barrier discharge lamp side with respect to the irradiation window (T1), and is provided from the dielectric barrier discharge lamp. Of the radiation light from the dielectric barrier discharge lamp is substantially the same as that of the irradiation window (T1) during the means for substantially preventing the emitted light from reaching the second lamp light emission amount measuring means (2). By installing a certain light transmissive window (T2), the light receiving portion of the second lamp light emission amount measuring means (F2) is completely disposed on the irradiation object (W) side with respect to the irradiation window (T1). If it is not possible, the same It can be the control of the second lamp emission amount, including degradation caused in the window (T1).

[Brief description of the drawings]

FIG. 1 is a diagram schematically showing a structure of a dielectric barrier discharge lamp.

FIG. 2 is a circuit diagram of the dielectric barrier discharge device of the present invention.

FIG. 3 is a schematic view of a dielectric barrier discharge device of the present invention.

FIG. 4 is a schematic view of a dielectric barrier discharge device of the present invention.

FIG. 5 is a circuit diagram as an embodiment of the dielectric barrier discharge device of the present invention.

[Explanation of symbols]

 G, G1, G2: discharge space Ea, Ea1, Ea2: electrode Eb, Eb1, Eb2: electrode D, D1, D2: dielectric B, B1, B2: dielectric barrier discharge lamp P: power supply device F1: first Lamp light amount measuring means F2: Second lamp light amount measuring means f1: First lamp light amount measuring signal f2: Second lamp light amount measuring signal S: Blocking means T1: Irradiation window T2: Light transmissivity window

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H05B 37/02-41/24 H01J 65/04

Claims (3)

(57) [Claims] 1. A discharge space (G, G1, G1) filled with a discharge gas for generating excimer molecules by a dielectric barrier discharge.
G2, ‥‥) and bipolar electrodes (Ea, Ea1, Ea2, Ea2) for inducing a discharge phenomenon in the discharge gas.
‥‥) A dielectric (D, D1, D1) between at least one of (Eb, Eb1, Eb2, ‥‥) and the discharge gas.
(2, ‥‥) and a dielectric barrier discharge lamp (B, B1, B2, ‥‥) having a structure interposed therebetween, and the electrodes (Ea, Ea1, Ea2, ‥‥) of the dielectric barrier discharge lamp.
(Eb, Eb1, Eb2,...) A power supply device (P) for applying a high AC voltage to the dielectric barrier discharge lamp (B, B1, B2,. )
The first lamp light emission amount measuring means (F
1) and a second lamp light emission amount measuring means (F2), wherein the power supply device (P) outputs a first lamp light emission amount measurement signal (F1) from the first lamp light emission amount measurement means (F1). f1)
And the power supplied to the dielectric barrier discharge lamps (B, B1, B2,...) Is feedback-controlled so that the error between the lamp emission amount target value signal (g1) indicating the target value of the lamp emission amount is reduced. Means for correcting the first lamp light emission amount measurement signal (f1) by a second lamp light emission amount measurement signal (f2) from the second lamp light emission amount measurement means (F2); A dielectric barrier discharge having means (S) for substantially preventing radiation emitted from the body barrier discharge lamps (B, B1, B2,...) From reaching the second lamp luminous intensity measuring means. apparatus. 2. The second lamp light emission amount measuring means (F2).
Are the dielectric barrier discharge lamps (B, B1, B2,.
‥) is installed in the vicinity of the place where the irradiation target (W) to be irradiated with the radiated light from ‥) is installed, and is radiated from the dielectric barrier discharge lamps (B, B1, B2, ‥‥). The second lamp light emission amount measuring means (F
By moving 2), light emitted from the dielectric barrier discharge lamps (B, B1, B2,...) Is substantially prevented from reaching the second lamp emission amount measuring means. The dielectric barrier discharge device according to claim 1. 3. The dielectric barrier discharge lamp (B, B1, B1).
B2, Δ) and the dielectric barrier discharge lamp (B, B
1, B2,...), Which has a structure in which the object to be irradiated (W) irradiated with light emitted from the light-emitting window (T1) is separated by a light-transmissive irradiation window (T1). Means (F
2) is installed on the side of the dielectric barrier discharge lamp (B, B1, B2,...) With respect to the irradiation window (T1), and the dielectric barrier discharge lamp (B, B1, B2,.
‥), the dielectric barrier discharge lamp (B, B1, B2, ‥‥) and the dielectric barrier discharge lamp (B) in a path where the radiated light from ‥) reaches the second lamp luminescence amount measuring means (F2). , B1, B2,...) Between the dielectric barrier discharge lamp (B, B1, B2) and the means (S) for substantially preventing the radiated light from reaching the second lamp luminescence amount measuring means. 2. The dielectric barrier discharge device according to claim 1, wherein a light-transmissive window (T2) is provided which has substantially the same deterioration characteristics as that of the irradiation window (T1) with respect to the radiation light from (1), (2). .