JPH10284281A - Discharge lamp lighting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a discharge lamp lighting device capable of stably lighting a discharge lamp of a relatively large lamp voltage while securing electrical safety. SOLUTION: A pulsating voltage obtained from rectification of ac power is applied between terminals (p), (q) and is stepped up by a chopper circuit 10. The output of the chopper circuit 10 is converted to a high frequency AC output by an inverter circuit 20. The output of the inverter circuit 20 is stepped up by an AC-AC converter circuit 30 and supplied to a discharge lamp La. The inverter circuit 20 adjusts the AC electric power of the output by changing a switching frequency with which switching elements Q2 , Q3 are alternately turned on and off by an inverter control circuit 21 at high frequencies. Also, when the rated voltage of the discharge lamp La is not less than 140 V, the inverter control circuit 21 regulates a dimming ratio lower limit value so that the lamp voltage is less than 300 V during dimming.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a discharge lamp lighting device.

[0002]

2. Description of the Related Art Conventionally, a discharge lamp lighting device for lighting a fluorescent lamp at a high frequency has a circuit configuration as shown in FIG. In the discharge lamp lighting device shown in FIG. 9, the pulsating voltage obtained by rectifying an AC power supply voltage terminal p, is applied between q, the pulsating voltage is smoothed by the smoothing capacitor C _0. An inverter circuit 20 is connected to both ends of the smoothing capacitor C ₀ , and an output of the inverter circuit 20 is supplied to a discharge lamp La as a load via an AC-AC conversion circuit 30.

The inverter circuit 20 includes a smoothing capacitor C
₀Switching element consisting of MOSFET at both ends
Q_Two, Q_ThreeConnected in series with one switching element
Child Q_ThreeAt both ends of the capacitor C₁And the inductor L_TwoWhen
Capacitor C_TwoConnected to a series circuit with a resonant circuit
It is. In addition, the inverter circuit 20 also includes a switch.
Switching element Q_Two, Q_ThreeConnected between the gate and source of
Zener diode ZD _Two, ZD_ThreeAnd switching
Element Q_Two, Q_ThreeAnd an inverter control circuit 21 for driving the
Have. Note that the inverter control circuit 21
Data control integrated circuits, switching element drive circuits, etc.
It is composed of

Here, the inverter circuit 20 is an inverter circuit.
Switching element Q by the_Two, Q_ThreeThe high
By turning on and off alternately with the frequency,
Sa C ₀DC inverter input voltage V_DC
Is the high frequency inverter output voltage V_HFHas been converted to. I
Inverter output voltage V of inverter circuit 20_HFIs AC-
Step-up transformer T of AC conversion circuit 30_TwoBoosted by
And supplied to the discharge lamp La.

[0005] Here, smaller than the load voltage V ₂ is the inverter input voltage V _DC voltage across the discharge lamp La, also the inverter output voltage V _HF is smaller than the load voltage V _2. By the way, the discharge lamp lighting device shown in FIG. 9 has a drawback that the idle period of the input current flowing from the AC power supply is lengthened and the harmonic distortion of the input current is increased. As shown in FIG. 10, a discharge lamp lighting device having a function of suppressing such input harmonic distortion has a chopper circuit 1.
A circuit configuration provided with 0 is known.

In the discharge lamp lighting device shown in FIG. 10, a pulsating voltage obtained by rectifying an AC power supply voltage is applied between terminals p and q, and this pulsating voltage is supplied to an inductor L ₁ and a switching element Q _1. , A diode D ₁ , a chopper control circuit 11 for controlling on / off of the switching element Q ₁ , a zener diode ZD ₁ , a smoothing capacitor C _0, and the like. The configuration of the inverter circuit 20 is substantially the same as that shown in FIG.
Capacitor C ₂ to form a resonance circuit, that are connected to both ends of the discharge lamp La to serve as the preheating capacitor of the discharge lamp La is different. Note that the discharge lamp lighting device shown in FIG. 10 does not include the AC-AC conversion circuit 30 shown in FIG.

The chopper circuit 10 includes a chopper control circuit 1
1 to turn on and off the switching element Q ₁ , so that the chopper input voltage E _DC, which is the voltage between the terminals p and q,
Is boosted and supplied to the inverter circuit 20. The inverter circuit 20 alternately turns on and off the switching elements Q ₂ and Q ₃ at high frequency by the inverter control circuit 21, thereby converting the inverter input voltage _VDC , which is the voltage across the smoothing capacitor C ₀ , to the high-frequency inverter output voltage V _HF . It is converted and supplied to the discharge lamp La.

Here, in the discharge lamp lighting device shown in FIG. 10, the inverter output voltage V _HF and the load voltage V ₂ are the same, and the chopper input voltage E _DC is smaller than the inverter input voltage V _DC. The input voltage E _DC is smaller than the load voltage V ₂ .

[0009]

However, in recent years,
In order to save resources and save energy, a discharge lamp with a small tube diameter and high efficiency and high output has been developed. This type of discharge lamp is a conventional fluorescent lamp (45 W / 32) shown in FIG.
Compared to the lamp voltage Vla of W), the lamp voltage Vla is higher as shown in FIG. Here, the lamp voltage Vla of the ring-shaped fluorescent lamp having a rated power of 68 W, and the lamp voltage Vla of a ring-shaped fluorescent lamp having a rated power of 97 W are shown. Here, the horizontal axis of FIG. 11 indicates the rated lamp current (Ila
This is the ratio of the lamp current (Ila) to the rated value (hereinafter referred to as the rated current ratio).

FIG. 11 will be described below. In the conventional fluorescent lamp (), when the rated current ratio is 1.0, the lamp voltage Vla is about 106 V, and the rated current ratio is 0.1 V.
At this time, the lamp voltage Vla was about 180 V. The conventional fluorescent lamp is not limited to this example, and almost no lamp has a lamp voltage Vla exceeding 300 V even during dimming. On the other hand, in a recently developed fluorescent lamp (,) having a small tube diameter and high efficiency and high output, the lamp voltage Vla exceeds 300 V when the rated current ratio is changed, that is, at the time of dimming. Electric shock may occur, and there is an electrical safety problem.

When the lamp voltage Vla is used at a voltage of 300 V or more, there is a problem in insulation, and the parts to be used are large, and it is difficult to reduce the size and weight of the apparatus. The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a discharge lamp lighting device capable of stably lighting a discharge lamp having a relatively large lamp voltage while ensuring electrical safety. It is in.

[0012]

According to a first aspect of the present invention, there is provided a discharge lamp lighting apparatus for lighting a discharge lamp having a rated lamp voltage of 140 V or more at a high frequency, in order to achieve the above object.
When the light output of the discharge lamp is controlled in the range of approximately 0.5% to approximately 100%, the lower limit of the dimming ratio is set to a lamp voltage of 300%.
And a dimming control means for controlling the voltage to be less than V.
When dimming a discharge lamp of more than V, the lamp voltage is 300V
Since the above can be prevented, a discharge lamp having a rated lamp voltage of 140 V or more can be stably lit while ensuring electrical safety.

According to a second aspect of the present invention, in the first aspect of the present invention, the discharge lamp includes a plurality of annular arc tubes each having an electrode at one end and a closed portion at the other end, the concentric circles being arranged in a concentric manner. The vicinity of the other ends of the plurality of ring-shaped arc tubes is joined by a bridge joint to form one discharge path inside, and the coldest spot is formed at the other end, and the one end And a ring-shaped fluorescent lamp having a base surrounding at least one of the other ends.

According to a third aspect of the present invention, in the second aspect, the annular fluorescent lamp has a rated lamp power of 68 W, a rated lamp current of 0.43 A, and a rated lamp voltage of 160 V. is there. The invention of claim 4 is
In the invention of claim 2, the ring-shaped fluorescent lamp is characterized in that the rated lamp power is 97 W, the rated lamp current is 0.43 A, and the rated lamp voltage is 229 V.

According to a fifth aspect of the present invention, in the first aspect, the discharge lamp has an optical path length of about 1400 mm to about 2500.
mm and a tube diameter of about 18 mm to about 29 mm. The invention according to claim 6 is the invention according to claim 1, further comprising an inverter circuit for supplying high-frequency power to the discharge lamp, wherein the oscillation frequency of the inverter circuit is
The frequency range is approximately 10 kHz to approximately 200 kHz.

According to a seventh aspect of the present invention, in the fourth aspect of the present invention, the dimming control means sets the ratio of the lamp current to the rated lamp current to 0.4 or more or sets the ratio of the luminous flux to the rated luminous flux to 70% or more. Is set. According to an eighth aspect of the present invention, in the third aspect, the dimming control unit sets the ratio of the lamp current to the rated lamp current to 0.1 or more, or sets the ratio of the luminous flux to the rated luminous flux to 30% or more. It is characterized by the following.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION

(Embodiment 1) A schematic block diagram and a circuit diagram of a discharge lamp lighting device of the present embodiment are shown in FIGS. The discharge lamp lighting device according to the present embodiment includes a chopper circuit 10 that converts a chopper input voltage E _DC composed of a pulsating voltage or a DC power supply voltage obtained by rectifying an AC power supply voltage into a DC inverter input voltage _VDC.
An inverter circuit 20 for converting the inverter input voltage _VDC into an AC inverter output voltage V _HF , and an AC-converting circuit for converting the inverter output voltage V _HF to an AC load voltage V _2.
It includes an AC conversion circuit 30 and a discharge lamp La as a load. Here, in the present embodiment, the inverter input voltage V
_DC is higher than the chopper input voltage E _DC , the inverter output voltage V _HF is lower than the inverter input voltage _VDC , and the load voltage V ₂ is higher than the inverter output voltage V _HF .

In the discharge lamp lighting device of the present embodiment shown in FIG. 1, a pulsating voltage obtained by rectifying an AC power supply is applied between terminals p and q, and this pulsating voltage is supplied to an inductor L ₁ and a switching element. Q ₁ , diode D ₁ , switching element Q ₁
Is boosted by a chopper circuit 10 including a chopper control circuit 11 for controlling on / off of the power supply, a zener diode ZD ₁ , and a smoothing capacitor C ₀ . Here, the chopper circuit 10 performs boosting and DC conversion while suppressing input current distortion as in the conventional example shown in FIG. The chopper control circuit 11 is configured by a chopper control integrated circuit, a first switching element driving circuit, and the like.

The inverter circuit 20 includes a smoothing capacitor C
₀Consisting of MOSFET connected to both ends of
Element Q_Two, Q_ThreeSeries circuit and one switching element
Child Q _ThreeC connected to both ends of₁And Indak
L_TwoAnd capacitor C_TwoSeries circuit with the resonance circuit of
Switching element Q_Two, Q_ThreeConnected between the gate and source
Zener diode ZD_Two, ZD_ThreeAnd Switchon
Element Q_Two, Q_ThreeAnd an inverter control circuit 21 for driving
It has. Note that the inverter control circuit 21
Barter control integrated circuit, second switching element driving circuit
Switching element Q_Two, Q_Threeof
Each gate has a resistor R_Two, R_ThreeConnected via
You.

[0020] The output of the inverter circuit 20, the discharge lamp La is connected via the AC-AC converter circuit 30 having a step-up transformer T _2. That is, the inverter circuit 20
Of connecting the primary winding n ₁ of the step-up transformer T ₂ across the capacitor C _2, is connected to the discharge lamp La in the secondary winding n ₂ of the step-up transformer T ₂ via a capacitor C _4. Further, the both ends of the discharge lamp La, the preheating capacitor C ₃ is connected.

The operation will be briefly described below. The chopper circuit 10 boosts the chopper input voltage E _DC applied between the terminals p and q by turning on and off the switching element Q ₁ by the chopper control circuit 11, and supplies the inverter input voltage V _DC across the smoothing capacitor C _0. Is to be obtained.

The inverter circuit 20 turns on and off the switching elements Q ₂ and Q ₃ alternately at a high frequency by the inverter control circuit 21, thereby converting the inverter input voltage _VDC , which is the voltage across the smoothing capacitor C ₀ , to the high-frequency inverter output voltage. Convert to _VHF . Inverter output voltage V _HF, which is the output of the inverter circuit 20 is supplied to be boosted discharge lamp La by the step-up transformer T ₂ of the AC-AC converter circuit 30.

In this embodiment, the amount of AC power output from the inverter circuit 20 is changed by changing the switching frequency of the switching elements Q ₂ and Q ₃ by the inverter control circuit 21 during preheating, starting, and lighting. I am adjusting. However, in the present embodiment, since the chopper circuit 10 is provided, the switching elements Q ₂ and Q ₃ , the resonance inductor L ₂ , and the capacitor C of the inverter circuit 20 are different from the conventional configuration shown in FIG.
_2, and the current value flowing through the AC-AC conversion circuit 30 and the like can be reduced.

Further, in the present embodiment, the provision of the AC-AC conversion circuit 30 allows the switching element Q ₁ , the inductor L ₁ , and the diode D _{1 of the} chopper circuit 10 to be different from the conventional configuration shown in FIG. , it is possible to reduce the voltage value and current value of the smoothing capacitor C _0. Further, the switching elements Q ₂ , Q
_3. The voltage values of the resonance inductor L ₂ and the capacitor C ₂ can be reduced.

In short, in this embodiment, since the chopper circuit 10 and the AC-AC conversion circuit 30 each perform boosting, even when the discharge lamp having the rated lamp voltage higher than the conventional one is operated at a high frequency, the chopper circuit 10 is turned on. And A
It is possible to make the step-up ratio of each of the C-AC conversion circuits 30 approximately the same as the conventional one. As a result, each of the circuits 10, 2
The electronic components 0 and 30 can be constituted by the same electronic components as those in the conventional case of lighting a discharge lamp having a relatively small rated lamp voltage at a high frequency.

For example, a voltage of 1200 V is required to stabilize the discharge lamp La having a higher rated lamp voltage than the conventional lamp, and the effective value of the lamp current is 0.43 A. In this case, if the power supply is AC 100 V and the output voltage of the chopper circuit 10 is 300 V, the boost ratio of the AC-AC conversion circuit 30 is about 4 (1200 V / 300 V), and the effective value of the output current of the inverter circuit 20 is 1 .72A (0.43
A × 4) or more is required.

In the present embodiment, the light output of a discharge lamp having a rated lamp voltage of 140 V or more as shown in FIG. 11 is controlled in the range of 0.5% to 100%. In addition, the switching frequency of the switching elements Q ₂ and Q ₃ by the inverter control circuit 21 is controlled so that the lamp voltage Vla does not exceed 300 V, thereby regulating the lower limit of the dimming ratio. In the present embodiment, the oscillation frequency of the inverter circuit 20 is set to about 10 kHz to about 2 kHz.
The frequency is set to 00 kHz, and the same electronic components as those used when the conventional discharge lamp is turned on in the inverter circuit 20 can be used.

However, in the present embodiment, when dimming a discharge lamp that requires a small lamp diameter, high efficiency, high output, and a high lamp voltage Vla, the lamp voltage Vla is prevented from becoming 300 V or more. It is possible to stably light this kind of discharge lamp while ensuring electrical safety. Note that the control of the switching element Q _2, Q ₃ by the inverter control circuit 21 may be controlled duty ratio with the switching frequency. Moreover, in the present embodiment, the lamp voltage Vla is always 300
Since the voltage is less than V, there is no longer a problem that the used parts become large due to the problem of insulation as in the conventional case, and it is possible to reduce the size, weight, and cost of the device.

In this embodiment, an annular fluorescent lamp as shown in FIGS. 3 and 4 is used as a discharge lamp having a small tube diameter, high efficiency, high output, and a high lamp voltage. In this ring-shaped fluorescent lamp, ring-shaped light emitting tubes 3A and 3B having electrodes (filaments) 5A and 5B at one end and a closed portion at the other end are concentrically arranged.
The vicinity of the other end of 3B is joined by a bridge joint 4 to form one discharge path inside, and the coldest spot is formed at the other end. A base part 6 surrounding both is provided.

This ring-shaped fluorescent lamp is a so-called top-cooled type lamp. The lamp voltage Vla has an ambient temperature dependency as shown in FIG. 5, and the lamp current Ila has an ambient temperature as shown in FIG. It has temperature dependence. That is, the lamp voltage Vl indicated when the ambient temperature is about 40 ° C.
a increases, and conversely, the lamp current Ila decreases. Therefore, the discharge lamp L composed of a ring-shaped fluorescent lamp
a characteristic of supplying a substantially constant current to the inverter circuit 2
If the temperature in the lighting apparatus is set to a temperature higher than 40 ° C. by setting the temperature to 0, the lamp voltage Vla decreases, so that the lower limit of the dimming ratio can be reduced, and the dimming range can be expanded. . Further, if the shade of the lighting equipment is made to be a sealed type, the temperature of the discharge lamp La can be further increased, so that the lamp voltage Vla is further reduced and the dimming range can be further expanded.

(Embodiment 2) FIG. 6 is a circuit diagram of a discharge lamp lighting device according to this embodiment. The basic configuration of this embodiment is substantially the same as the first embodiment, differs in that it has a preheating circuit 40 in place of the preheating capacitor C ₃ in the first embodiment. Since the configuration other than the preheating circuit 40 is the same as that of the first embodiment, the same reference numerals are given and the description is omitted.

The preheating circuit 40 comprises a preheating transformer T ₁ and capacitors C ₅ , C ₆ and C _{7. The} primary winding of the preheating transformer T _{1 is connected to} the primary winding of the step-up transformer T ₂ via the capacitor C _5. The two secondary windings of the preheating transformer T ₁ are connected in parallel to the capacitors C ₆ ,
It is connected to both filaments of the discharge lamp La via a C _7. Here, the inverter circuit 20 and the preheating circuit 40 have independent resonance characteristics.

The operation will be described below. This embodiment
Then, at the time of preheating, the inverter control circuit 21 switches
Switching element Q_Two, Q_ThreeOn and off alternately at high frequency
The preheating transformer T ₁And capacitor C_Five
Resonates and supplies high-frequency power to the filament of the discharge lamp La.
Pay. Also in the present embodiment, similarly to the first embodiment,
At the time of preheating, at the time of starting, and
Switching element Q_Two, Q_ThreeSwitch
The output from the inverter circuit 20 by changing the switching frequency.
The amount of AC power to be applied is adjusted.

In the present embodiment, the use of the preheating transformer T ₁ makes it easier to control the amount of AC power during preheating than in the first embodiment using only the preheating capacitor C _3. Preheating capacitor C ₃
Can be prevented from increasing, and deterioration (lifetime deterioration) of the discharge lamp La can be prevented. In each of the above embodiments, the chopper circuit 10 is configured by a boost chopper system, but may be configured by a switched capacitor system or the like. In the present embodiment, the inverter circuit 2
Although 0 is configured by a half-bridge system, it may be configured by a full-bridge system, a push-pull system, a one-stone system, a switched capacitor system, or the like. Further, in the present embodiment, the AC-AC conversion circuit 30 is configured by a step-up transformer system, but may be configured by a switched capacitor system or the like.

[0035]

【Example】

(Embodiment 1) In the present embodiment, in the discharge lamp lighting device having the circuit configuration shown in FIG. 1, the discharge lamp La has a ring shape having a rated lamp power of 97 W, a rated lamp current of 0.43 A, and a rated lamp voltage of 229 V. A case where a fluorescent lamp is used will be described. The light output of the discharge lamp La is 0.5% to 1%.
If the dimming range of 00% is controlled without setting the lower limit of the dimming ratio, the lamp voltage Vla changes as shown in FIG. The horizontal axis in FIG. 7 is the rated current ratio.

On the other hand, the inverter control circuit 21 of the present embodiment controls the switching element Q so that the rated current ratio becomes 0.4 or more when changing the lamp current Ila.
_The switching elements Q ₂ , Q ₃ are controlled such that the switching frequency of the switching elements Q ₂ and Q ₃ is controlled or the ratio of the light flux to the rated light flux (hereinafter referred to as the rated light flux ratio) becomes 70% or more.
To control the switching frequency of the Q _3. By performing such control, it was possible to prevent the lamp voltage Vla from becoming 300 V or more, and even when dimming the ring-shaped fluorescent lamp, it was possible to perform stable lighting while ensuring electrical safety.

Embodiment 2 In this embodiment, in the discharge lamp lighting device having the circuit configuration shown in FIG. 1, the discharge lamp La has a rated lamp power of 68 W and a rated lamp current of 0.4 W.
A case where a ring-shaped fluorescent lamp having a rated lamp voltage of 160 V and 3 A is used will be described. If the light output of the discharge lamp La is controlled without setting the dimming ratio lower limit value in the dimming range of 0.5% to 100%, the lamp voltage Vla changes as shown in FIG. The horizontal axis in FIG. 8 is the rated current ratio.

On the other hand, the inverter control circuit 21 of the present embodiment controls the switching element Q so that the rated current ratio becomes 0.1 or more when changing the lamp current Ila.
_The switching elements Q ₂ , Q ₃ are controlled such that the switching frequency of the switching elements Q ₂ and Q ₃ is controlled, or the ratio of the light flux to the rated light flux (hereinafter referred to as the rated light flux ratio) becomes 30% or more.
To control the switching frequency of the Q _3. By performing such control, it was possible to prevent the lamp voltage Vla from becoming 300 V or more, and even when dimming the ring-shaped fluorescent lamp, it was possible to perform stable lighting while ensuring electrical safety.

The annular fluorescent lamp used in each of the above embodiments has an optical path length (discharge path length) of about 1400 mm to about 25 mm.
00 mm, and the tube diameter is approximately 18 mm to approximately 29 mm.

[0040]

According to the first aspect of the present invention, the rated lamp voltage is 1
A discharge lamp lighting device for lighting a discharge lamp of 40 V or higher at a high frequency, wherein the light output of the discharge lamp is approximately 0.5% to approximately 100%.
In the case where the dimming control is performed in the range, the dimming regulating means for regulating the dimming ratio lower limit value so that the lamp voltage is less than 300 V is provided, so that the dimming is performed on the discharge lamp having the rated lamp voltage of 140 V or more. In this case, it is possible to prevent the lamp voltage from becoming 300 V or more.
There is an effect that the discharge lamp of V or more can be stably lit while ensuring electrical safety.

The inventions of claims 2 to 8 also
There is an effect similar to that of the first aspect.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing a first embodiment.

FIG. 2 is a schematic block diagram of the above.

FIG. 3 is an external view of a discharge lamp used in the above.

FIG. 4 is a schematic external view of a main part of the discharge lamp used in the above lamp with a base portion removed.

FIG. 5 is an operation explanatory view of the above.

FIG. 6 is a circuit diagram showing a second embodiment.

FIG. 7 is an explanatory diagram of the first embodiment.

FIG. 8 is an explanatory diagram of a second embodiment.

FIG. 9 is a circuit diagram showing a conventional example.

FIG. 10 is a circuit diagram showing another conventional example.

FIG. 11 is an explanatory diagram of a lamp voltage of a fluorescent lamp.

[Explanation of symbols]

10 chopper circuit 11 chopper control circuit 20 inverter circuit 21 inverter control circuit 30 AC-AC conversion circuit Q ₁ switching element Q _2, Q ₃ switching element T ₂ boosting transformer La discharge lamp C ₀ smoothing capacitor C ₃ preheating capacitor

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Akihiro Kishimoto 1048 Kadoma Kadoma, Osaka Pref.Matsushita Electric Works, Ltd. 72) Inventor Hiroshi Aoki 1048 Kazuma Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Works, Ltd.

Claims (8)

[Claims] 1. A discharge lamp lighting device for driving a discharge lamp having a rated lamp voltage of 140 V or higher at a high frequency, wherein the light output of the discharge lamp is controlled in a range of approximately 0.5% to approximately 100%. A discharge lamp lighting device comprising: a dimming control unit that controls a dimming ratio lower limit value so that a lamp voltage is less than 300 V. 2. A discharge lamp, comprising: a plurality of ring-shaped arc tubes each having an electrode at one end and a closed portion at the other end; Joined by a bridge joint, one discharge path is formed inside, a coldest spot is formed at the other end, and surrounds at least one of the one end and the other end. The discharge lamp lighting device according to claim 1, wherein the discharge lamp lighting device is a ring-shaped fluorescent lamp having a base. 3. The annular fluorescent lamp has a rated lamp power of 6
3. The discharge lamp lighting device according to claim 2, wherein the rated lamp current is 8 W, the rated lamp current is 0.43 A, and the rated lamp voltage is 160 V. 4. The annular fluorescent lamp has a rated lamp power of 9
The discharge lamp lighting device according to claim 2, wherein the rated lamp current is 7 W, the rated lamp current is 0.43A, and the rated lamp voltage is 229V. 5. The discharge lamp has an optical path length of about 1400 mm to about 2500 mm and a tube diameter of about 18 mm to about 29 mm.
The discharge lamp lighting device according to claim 1, wherein the distance is in mm. 6. An inverter circuit for supplying high-frequency power to a discharge lamp, wherein the oscillation frequency of the inverter circuit is approximately 10
The discharge lamp lighting device according to claim 1, wherein the frequency is in the range of kHz to approximately 200 kHz. 7. The light control device according to claim 4, wherein the ratio of the lamp current to the rated lamp current is set to 0.4 or more, or the ratio of the luminous flux to the rated luminous flux is set to 70% or more. Discharge lamp lighting device. 8. The light control device according to claim 3, wherein the ratio of the lamp current to the rated lamp current is set to 0.1 or more, or the ratio of the luminous flux to the rated light flux is set to 30% or more. Discharge lamp lighting device.