JPS5963655A - Lighting device for metal halide lamp - Google Patents

Abstract

PURPOSE:To enable reactivation of a metal halide lamp to be carried out simply, and maintain arc discharge directly by means of commercial voltage automatically after the reactivation by applying both the voltage of a commercial power source and the output voltage of a a high-frequency high-voltage circuit across the main electrodes. CONSTITUTION:In a high-frequency-voltage producing circuit 4, commercial voltage is converted into high frequency voltage while being increased several times to more than ten times before being supplied to a step-up circuit 5. The step- up circuit 5 increases the thus obtained high frequency voltage several times. As a whole, high frequency high voltage increased considerably higher than the commercial voltage is obtained through the above voltage-increasing operations performed by the high-frequency-voltage producing circuit 4 and the step-up circuit 5. Between the main electrodes (A) and (A') of a metal halide lamp 1, the thus increased high frequency high voltage is applied in addition to the commercial voltage. First, arc discharge is carried out between the main electrode (A) and an auxiliary electrode (C) by means of the high frequency high voltage. Following that, arc discharge is induced between the main electrodes (A) and (A') by means of the commercial voltage.

Description

Detailed Description of the Invention (a1 Technical Field Related to the Invention - This invention relates to a lighting device for a metal halide lamp containing a metal halide such as thallium iodide, which is used as a high-efficiency white light source.

(b) Background of the Invention Metal halide lamps have the advantage of being highly efficient and high color rendering light sources, but have the disadvantage that after initial startup, the internal pressure becomes very high, making restarting difficult. In particular, when attempting to restart at a low frequency, it is necessary to apply a voltage of several tens of KV or more with an interelectrode gap of several tens of meters to several tens of meters+m. However, in addition to the above-mentioned advantages as a light source, this main lamp does not require restarting every half cycle, unlike fluorescent lamps, once restarted. Another advantage is that restarting at a high frequency requires only a fraction of the voltage applied.

(e) Purpose of the Invention The present invention has been made in view of the above, and is capable of simply restarting, and after restarting, direct arc discharge is automatically maintained at commercial voltage. The object of the present invention is to provide a metal halide lamp lighting device in which the single salt terminal of the metal halide lamp can be replaced with two terminals.

(d) Structure of the invention This invention can be summarized as follows.

The electrode structure of a metal halide lamp consists of a pair of opposing main electrodes and an auxiliary electrode attached to one of the main electrodes via a dielectric and closely opposing the other main electrode. By attaching an auxiliary electrode to one main electrode via a dielectric, the metal halide lamp has two electrode terminals.
Become an individual.

In order to restart the metal halide lamp having the above structure, a high frequency high voltage circuit driven by a commercial power supply is provided, and a voltage obtained by superimposing the output of this high frequency high voltage circuit and the commercial power supply voltage is applied to the two electrode terminals, Zunawaji should be applied between the main electrodes.

With the above configuration, when the commercial power source is turned on at the time of restart, a voltage in which the commercial power source voltage (low frequency AC voltage) and the high frequency high voltage are superimposed is applied between the main electrodes of the metal halide lamp. This superimposed voltage is applied simultaneously between the main electrodes and between the auxiliary electrode and the other main electrode via the dielectric, but the gap between the auxiliary electrode and the other main electrode is closer than the gap between the main electrodes. First of all, this auxiliary electrode because it is short.

Arc discharge occurs between the main electrodes. The arc discharge between the auxiliary electrode and the main electrode rapidly increases the conductivity between the main electrodes in the tube. As a result, arc discharge is induced between the main electrodes. On the other hand, when arc discharge occurs between the auxiliary electrode and the main electrode, a large voltage drop occurs across the dielectric due to the discharge current.

Therefore, the voltage applied between the auxiliary electrode and the main electrode is drastically reduced, and the arc discharge between the electrodes is stopped. Once arc discharge occurs between the main electrodes, the highly excited state inside the tube is maintained, so the arc discharge is maintained by the commercial power supply voltage.

(e) Description of Embodiments FIG. 1 shows an example of a metal halide lamp used in a metal halide lamp lighting device according to an embodiment of the present invention. Further, FIG. 2 is a basic block diagram of the lighting device. 'The metal halide lamp 1 has a double-end type shape, and main electrode terminals 10 and 11 are attached to both ends of the lamp. The main electrode terminals 10, 11 are connected to the main electrodes A, A' in the stem 12.13 via a molybdenum foil 14.15.

This molybdenum foil 14.15 is attached to the stem 12.
This is to alleviate the thermal stress difference generated between the main electrode terminal 13 and the main electrode terminal. A ceramic cylinder 16 that forms a cabbage multi-dissipation for high frequency waves is fixed to the main electrode A, and an auxiliary electrode C is completely attached to the periphery of this ceramic cylinder 16.

The main electrodes A, A'' face each other, and the main electrode A'
and auxiliary electrode C are opposed to each other. The gap between main electrodes A and A' is set larger than the gap between main electrode A and auxiliary electrode C, and the discharge path formed by the latter gap spatially crosses the discharge path formed by the former gap. I try not to.

In Figure 2, a low frequency and low voltage commercial power supply 2b,
It is connected to a high frequency voltage generation circuit 4 via a current limiting inductor 3 . The high-frequency voltage generating circuit 4 itself generates a voltage several times to several tens of times higher than the voltage of the commercial power supply 1, but it does not reach the voltage required to restart the metal halide lamp 1. The output of the high frequency generation circuit 4 is the step-up circuit 5
The pressure is boosted by The step-up ratio is set to be large enough to obtain the high frequency and high voltage necessary to restart the metal halide lamp I. The boosted high frequency voltage is superimposed on the commercial voltage and is applied to the main electrode A of the metal halide lamp 1.

It is applied between A'.・. The step-up circuit 5 and the high frequency voltage generation circuit 4 constitute the high frequency high voltage circuit of the present invention.

Note that the step-up circuit 5 includes a metal halide lamp 1 that does not operate at low frequencies and uses commercial voltage almost as it is.
The high-frequency voltage generating circuit 4 is one that stops operating when the metal halide lamp 1 causes arc discharge and the voltage across it drops.

In the above configuration, when the commercial power supply 2 is turned on while the metal halide lamp 1 has not been restarted, the voltage is applied to the high frequency voltage generation circuit 4. The high-frequency voltage generating circuit 4 converts the commercial voltage into a high-frequency voltage, boosts the voltage by several times to several times 1O, and supplies the voltage to the step-up circuit 5 . The step-up circuit 5 further boosts the high frequency voltage several times. Due to the above-described voltage boosting effect by the high frequency voltage generating circuit 4 and the step-up circuit 5, a high frequency high voltage approximately several lθ times the commercial voltage can be obtained as a whole.

The above boosted high frequency high voltage is applied between the main electrodes of the metal halide lamp 1 in a manner superimposed on the commercial voltage. Here, with respect to the gap between main electrodes A and A', main electrode A'
-9 Since the gap between the auxiliary electrodes C is short, when the above voltage is applied between the main electrodes, arc discharge occurs between the main electrode A' and the auxiliary electrode C. When this arc discharge occurs, the ionized ions rapidly increase and diffuse within the tube, so that the discharge starting voltage between the main electrodes A and A' decreases rapidly.

Therefore, at approximately the same time that an arc discharge occurs between electrodes A' and C, an arc discharge occurs between electrodes A and A' due to the low voltage. On the other hand, when an arc discharge occurs between the main electrode A' and the auxiliary electrode C, a large voltage drop occurs in the ceramic tube 16 forming the capacitance. Therefore,
When arc discharge occurs between electrodes A' and C, the arc discharge stops almost immediately. Furthermore, in this embodiment, the high-frequency voltage generating circuit 4 used is one that stops operating due to voltage drop when arc discharge starts between the main electrodes of the metal halide lamp l and the impedance decreases. If an arc discharge occurs between the main electrodes, the high frequency high voltage will no longer be applied between the main electrodes.

As described above, an arc discharge is first caused by high frequency and high voltage between the main electrode A' and the auxiliary electrode C, and then, induced by the arc discharge, a commercial voltage is applied to the main electrodes A and A.
Arc discharge begins between ' - - When arc discharge begins between alternating electrodes A and A, arc discharge continues as long as the commercial power supply is not cut off since the inside of the tube is kept in a highly excited state. .

FIG. 3 shows a specific example of the above metal halide lamp lighting device.

- The gap between the main electrodes A and A' in the metal halide lamp 1 is set to approximately several cranes, and the main electrode A'.

The gap between the auxiliary electrodes C is set to approximately 0.5 to l m+s. Metal halides such as thallium iodide, sodium iodide, and indium iodide are sealed inside the tube, and the overall size is relatively small.

The high frequency voltage generation circuit 4 includes an oscillation capacitor 40, a thyristor 41 . It is composed of a series circuit of a nonlinear inductor 42 and an intermittent capacitor 43. This circuit is an oscillation booster circuit that performs oscillation boosting by the cooperation of an oscillation capacitor 40 and a nonlinear inductor 42 when a commercial voltage is applied. The intermittent capacitor 43 repeats charging and discharging according to the input voltage, and performs the oscillation boosting action every half cycle of the commercial voltage.

The step-up circuit 5 is composed of a step-up transformer 5'. The boost ratio is several times to ten times higher. Note that 6 is a resistor that applies a positive bias to the thyristor 41.

In the above configuration, first, when the commercial power supply 2 is turned on, the oscillation capacitor 40 is charged via the current limiting inductor 3, and when the terminal voltage reaches the breakover voltage of the thyristor 41, the thyristor 41 becomes conductive. A step-up oscillation operation is started by the cooperation of the oscillation capacitor 40 and the step-up nonlinear inductor 42. This operation occurs at the beginning of each half cycle of the mains voltage due to the action of the intermittent capacitor 43.

Due to the above-described operation at the beginning of the multiplication cycle, a high frequency voltage several times the commercial power supply voltage is intermittently generated in the secondary winding of the step-up transformer 5'.

The step-up transformer 5' further steps up the high-frequency voltage according to the turns ratio, and the main electrodes A, A of the metal halide lamp 1
Note that the oscillation capacitor 40 has high impedance for low frequencies, and the step-up transformer 5
Since '' has a low impedance with respect to low frequencies, the commercial voltage is also applied almost as is, superimposed on the above-mentioned high frequency high voltage, between the main electrodes A and A'.

Due to the above operation, the high frequency and high voltage is applied to the ceramic cylinder 16.
A voltage is applied between the auxiliary electrode C2 and the main electrode A' through the auxiliary electrode C2, and an arc discharge occurs between the two electrodes.

) Auxiliary/Auxiliary Electrode C2 When an arc discharge occurs between the main electrode A', an arc discharge starts almost simultaneously between the main electrodes A and A'. In addition, the auxiliary electrode C2 main electrode Δ'
When an arc discharge occurs between the auxiliary electrode C2 and the main electrode A', a large voltage drop occurs in the capacitor of the ceramic tube 16, and the arc discharge between the auxiliary electrode C2 and the main electrode A' is stopped. And main electrodes A, A
When arc discharge begins between the two main electrodes, the voltage between the main electrodes becomes equal to or less than the breakover voltage of the Cyrisk 41, and the operation of the high-frequency voltage generating circuit 4 is stopped. Thereafter, the interior of the metal halide lamp I is kept in a highly excited state, so that arc discharge between the main electrodes A and A is maintained by the commercial voltage.

In the above embodiments, a step-up transformer is used as the step-up circuit, but an LC series resonant step-up circuit may also be used. Furthermore, the step-up circuit 5 may be configured with multiple stages instead of one stage.

(f) Effects of the invention As described above, according to the invention, it is possible to easily restart a metal halide lamp, and since the auxiliary electrode is attached to the main electrode via a dielectric, When restarted, the application of high frequency and high voltage is automatically stopped due to the voltage drop across the dielectric, maintaining low voltage arc discharge in the main discharge path. Therefore, the starting of metal halide lamps, which was conventionally slow, can be easily, stably, and safely realized. Furthermore, since the metal halide lamp has two electrode terminals, the configuration of the starter is simplified, and the number of connections is reduced, which has the effect of increasing operational reliability.

[Brief explanation of drawings]

FIG. 1 shows an example of a metal halide lamp used in a metal halide lamp lighting device according to an embodiment of the present invention. Further, FIG. 2 is a basic block diagram of the lighting device. FIG. 3 is a circuit diagram showing a specific example of the lighting device. 1-metal halide lamp, 10 (11)-main electrode terminal, 16-ceramic tube (dielectric), 2-commercial power supply, 4
- High-frequency voltage half-circuit, 5- Step-up circuit, A (
A') - Live electrode C - Auxiliary electrode.・. ζ Applicant: Nippon Shinnichi, Attorney at Denki Co., Ltd. Patent Attorney: Hisao Komori 1981 Patent Application No. 173'596 21 Name of Invention Metal Halide Lamp Dot Illusion 53. Person making amendment, relationship with tenancy - Patent Applicant Tokyo Contact number Tokyo (03) 454-5111 Full text of the specification subject to the 5th amendment Contents of the 6th amendment As shown in the attached amended specification. Name of the invention in the revised description. High-Intensity Discharge Lamp Starting and Lighting Device 2, Claims %) A pair of opposing main electrodes, and one of the main electrodes is attached via a 1tcvs' electric body, and is closely opposed to the other main electrode. High frequency 1! It has a high-intensity discharge lamp with poles arranged within 1.5 cm, and a high-frequency high-voltage circuit driven by a commercial power source, and the voltage of the commercial power source and the output voltage of the high-frequency high-voltage circuit are superimposed to generate a high-intensity discharge lamp. A m, ill is applied between the main electrodes of the lamp. mix Rambuy lighting device. Detailed Description of the Invention (a) Technical field to which the invention pertains The invention relates to a method for starting a high-intensity flash lamp, typified by a metal pallite lamp, containing a metal halide such as scandium, which is used as a high-efficiency white light source. Relating to a lighting device. (b) Background of the Invention High-intensity discharge lamps such as metal pallite lamps have high yields. Ah, the color rendering, the art. However, after the initial start, the internal pressure becomes extremely high, making it difficult to restart. In other words, in general metal pallite lamps, first a low pressure 70 discharge is generated between the main electrode and the auxiliary electrode, so the starting voltage is low and the initial start is very easy, but the inside of the arc tube is exposed to high temperature and high pressure. When the starting voltage is reached, the starting voltage will be several 1 with a gap between t & of several ■ to several low.
It reaches over 0KV. (c) Purpose of the Invention This invention has been made in view of the above, and allows easy restarting, and once restarted, direct arc discharge is automatically maintained at commercial voltage, and furthermore, The present invention is summarized as follows: 11-pole structure of a high-intensity discharge lamp. The structure consists of a pair of opposing main electrodes, and a high-frequency electrode attached to one of the main electrodes via a dielectric and facing the other main electrode in close proximity. By attaching the high-frequency electrode through the IF and 'Th terminals of the high-intensity discharge lamp, there are two terminals. In order to restart the high-intensity discharge lamp with the above structure, the A high-frequency high-voltage circuit is provided, and a voltage obtained by superimposing the output of this high-frequency high-voltage circuit and the commercial power supply voltage is applied between the two electrode terminals, that is, the main 1! pole.With the above configuration, restarting is possible. When the commercial power is turned on, a superimposed voltage of the commercial power supply voltage (low-frequency AC voltage) and high-frequency high voltage is applied between the main 1!E electrodes of the high-intensity discharge lamp. The high frequency 12E& is applied simultaneously between the high frequency electrode and the other main electrode via the dielectric, but first, this high frequency! ! . High frequency arc discharge occurs between the main electrodes. high frequency electrode,
The high frequency arc discharge between the main electrodes greatly increases the conductance between the main tTh within the tube. As a result, low-frequency arc discharge is induced between the main power lines. On the other hand, high frequency! When a low frequency arc discharge occurs between the pole and main electrode, the discharge!
The current causes a large voltage drop across the dielectric. Therefore, the voltage applied between the high-frequency electrode and the main electrode is drastically reduced, which prevents low-frequency arc discharge between the electric connections, and when -H low-frequency arc discharge occurs between the main electrodes, the tube voltage decreases. The operation of the high-frequency, high-voltage circuit is stopped, and since the highly excited state inside the tube is maintained, the low-frequency arc discharge is maintained by the commercial power. (e) Description of the Embodiment FIG. 1 shows an example of a metal pallite lamp used in a metal oxide lamp lighting device according to an embodiment of the present invention. Moreover, the stripe diagram 2 is a basic block diagram of the same lighting device. The metal paralite lamp l has a double-end type shape, with main ttIk terminals IQ and 1 at both ends of the lamp.
1 is attached. The main T& terminals 10.11 are connected to the main electrodes A, A' via molybdenum foils 14, 15 within the crush seals 12, 13. This molybdenum foil 1
4.15 is a known method for alleviating the thermal stress difference that occurs between the stem 12° 13 and the main electrode terminal at high temperatures. A ceramic tube 16 that provides a capacitance to high frequencies is fixed to the main tikA, and a high frequency electrode 0 is attached around this seven ramic tube 16. Note that the main electrodes A and A' are provided with electron emitting materials such as thorium, if necessary.The main electrodes A and A' face each other, and
Main 1 & □ Yotaka Anha, Extreme. ka, facing each other. , 6° is set larger than the gap between the main electrodes A and A' and the high-frequency electric current IkO. In Figure 2, all low-frequency and low-voltage commercial
Although it generates a voltage several times as large as ~1O, it is less than the voltage required to restart the metal rewrite lamp l. The output of the high-frequency voltage generator 4 is boosted by a step-up circuit. The step-up ratio is set to be large enough to obtain the high frequency and high voltage necessary to restart the metal paralyte trap I. The boosted high frequency voltage is superimposed on the commercial voltage and is applied to the main IEIA, A'11IK mark of the metal paralite lamp l. The step-up circuit 5 and the high frequency voltage generation circuit 4 constitute the high frequency high voltage circuit of the present invention. Note that the step-up circuit 5 is equipped with a metal paralite lamp that does not operate at low frequencies and uses commercial voltage almost as it is.
The high-frequency voltage generating circuit 4 is one that stops operating when the metal paralite lamp 1 causes low-frequency arc discharge and the voltage across it drops. In the above configuration, the metal paralite lamp l that is lit
When the commercial power source 2 is turned on while the power source 2 is still in a high-temperature high-pressure network after being turned off, the voltage is applied to the high-frequency voltage generation circuit 4. The high-frequency voltage generation circuit 4 converts the theoretical voltage into a high-frequency voltage, boosts it several times to 1-0 times, and supplies it to the step-up circuit 5. The step-up circuit 5 is
The high frequency voltage is further boosted several times to several tens of times. High frequency voltage generation circuit 4 and step-up circuit 5
Due to the boosting effect described above, the total commercial voltage can be reduced by several tens of
About twice as high frequency and high voltage can be obtained. One or more boosted high frequency high voltages are applied between the main electrodes of the metal paralite lamp l, superimposed on the commercial voltage. Here, since the gap between the main pole A' and the high frequency electrode C is short, when the above voltage is applied between the main electrodes, the main current fIk
A high-frequency arc discharge occurs at the pole Oi!+.When this high-frequency arc discharge occurs, the separated ions rapidly increase and diffuse into the tube, so the main electrodes A, A''
Free time! Onset - pressure drops rapidly. Therefore, when a low-frequency arc discharge occurs between the electrodes A', anh, the main electrode A', and the high-frequency electrode O, a large voltage drop occurs in the ceramic @ l 6 which has a high capacitance. Therefore, when a low frequency arc discharge occurs between tIkA'' and 0, the high frequency arc discharge stops almost immediately.In addition, in this practical example, the high frequency voltage generation circuit 4
As, between the main electrodes e of the metal paralite lamp l (low frequency arc discharge starts and its impedance decreases, the main electrodes A, A' When a low-frequency temporary arc discharge i (occurs), high-frequency high voltage is no longer applied between the main electrodes tThA' and the high-frequency electrode O.
A high-frequency arc discharge occurs between the main 111iA and A'' due to the high-frequency high voltage, and then, induced by the high-frequency arc discharge, a low-frequency arc discharge is started and restarted between the main 111iA and A'' by the commercial voltage. - Alternate 1! pole A. When low frequency arc discharge starts between A', the inside of the tube becomes high f11.
Since it is kept in the active state, low-frequency arc discharge will be maintained unless the commercial power supply is cut off. FIG. 3 shows a specific example of the above metal halide lamp lighting device. Main tfijl in metal halide lamp l! The gap between A and A'' is set to approximately a few ranges, and the gap between main tiji A' and high frequency gap C is set to #'! A rare gas such as a tetragenide and argon is sealed in a metal such as, and its body is relatively small.The high-frequency voltage generating circuit 4 includes an oscillation capacitor 40° thyristor 41', a nonlinear inductor 42, and an intermittent oscillation capacitor 43. This circuit is an oscillating booster circuit that performs oscillation boosting by the cooperative action of an energizing capacitor 40 and a nonlinear inductor 42 when a commercial voltage is applied. An intermittent capacitor 43 is connected to an input voltage Charging and discharging are repeated according to the voltage, and the above oscillation boosting action is performed every half cycle of the commercial voltage.It is composed of a step-up circuit 51'i and a step-up transformer 5'.The step-up ratio is several times to several tens of times. Note that 6 is a resistor that applies a positive bias to the thyristor 41. In the above configuration, first, the commercial power supply 2 is turned on, and the oscillation capacitor 4.0 is charged via the current limiting inverter 3. When the terminal voltage reaches the breakover voltage of the thyristor 41, the thyristor 41 becomes conductive and a step-up oscillation operation starts due to the cooperation between the oscillation capacitor 40 and the step-up nonlinear inductor 42. 43 occurs at the beginning of each half cycle of the mains voltage.The above operation at the beginning of the multiplication cycle causes an intermittent high-frequency 11 current of large amplitude to flow through the primary winding of the step-up transformer 5'. The booster transformer 5' further boosts the high frequency high voltage according to the turns ratio, and the main of the metal pararite lamp 1 is connected to the pole A,
Apply between A'. Note that the boost capacitor 4o has high impedance for low frequencies. Well, since the primary step-up transformer 5' has low impedance and dance with respect to low frequencies, the commercial voltage is applied almost as is, superimposed on the above-mentioned high-frequency high voltage, between the main poles A and A'. Ru. Due to the above operation, the high frequency and high voltage is applied to the ceramic cylinder 16.
When a high frequency is applied between the pole C1 and the main electrode Ar, and a high frequency arc discharge occurs between the two electrodes, the main electrode A is immediately attracted by it.
, A' also starts low frequency arc discharge and is restarted. Also, high frequency electric & 0. When a low-frequency arc discharge occurs between the main electrodes A'', a large voltage drop occurs due to the capacitance of the ceramic tube 16, and the high-frequency electrode C2 main IIt pole A
′ prevents high-frequency arc discharge between And main electrode A
, A' starts, the voltage between the main electrodes becomes less than the breakover voltage of the thyristor 41, and the operation of the high frequency voltage generation circuit 4 stops. Thereafter, since the inside of the metallolide lamp l is kept in a highly excited state, the low-frequency arc discharge between the main electrodes A and A' is maintained by the commercial voltage. In FIG. 3, one end of the secondary winding of the step-up transformer 5' is connected to the connection point between the primary winding and the oscillation capacitor 40, but the connection between the primary winding and the intermittent oscillation capacitor 43 is # It is of course possible to connect to a continuation point. In the above embodiments, a step-up circuit may also be used. Moreover, you may combine these. Furthermore, step 7.71 circuit 5 is S-configured not in one stage but in several stages.
You may. . (f) Effects of the invention As described above, according to the present invention, a high-intensity discharge lamp such as a metal noride lamp can be easily restarted, and a high-frequency gate can be connected via a dielectric material. , because it is attached to the main electrode, when restarted, the application of high frequency and high voltage is automatically stopped due to the voltage drop across the dielectric.
4, and the low voltage arc discharge of the arc frequency is maintained in the +/- electric path. Therefore, starting of a high-intensity discharge lamp, which has been a difficult task, can be easily, stably, and safely realized. Furthermore, since the high-intensity discharge lamp has two T& terminals, the configuration of the starting equipment is simple, and there are fewer connections, which has the effect of increasing operational reliability. Description: An example of a metallone-ride lamp used in a playing card lighting device. FIG. 2 shows the basic block 1 of the lighting device. Figure 1 is a circuit diagram showing the specific fl+ of the above lighting device.
High intensity discharge lamp (metal noride lamp). 10.(Collection) - Main electrode terminal, 16 - Ceramic tube (dielectric), 2 - Commercial power supply, 4 - High frequency voltage generation circuit. A (A″) - main electrode, C - high frequency electrode.

Claims (1)

[Claims] (11') A metal halide lamp with a pair of opposing main electrodes, an auxiliary electrode attached to one of the main electrodes via a dielectric, and an auxiliary electrode closely opposing the other main electrode, which is connected to a commercial power source. a driven high-frequency high-voltage circuit, and the metal halide lamp lighting device is configured to apply the voltage of the commercial power source and the output voltage of the high-frequency high-voltage circuit in a superimposed manner between the main electrodes of the metal halide lamp. .