JPH088080A - Electrodeless discharge lamp lighting device - Google Patents

Abstract

PURPOSE:To enable optimum frequencies to be set when starting up an electrodeless discharge lamp and when keeping the lamp turned on so as to achieve high efficiency and miniaturization of a device by controlling the electrodeless discharge lamp from a started state to a lighted-up state by the switching of first and second power supply means from one to the other. CONSTITUTION:A power supply means 1b supplying sufficient power to a high- frequency power supply coil 2 to start up an electrodeless discharge lamp 3 and having high frequencies, and a power supply means 1c supplying sufficient rated power to the coil 2 to keep the discharge lamp 3 lighted-up and having low frequencies, are provided. A switching element SW1 is switched so that at the startup of the discharge lamp 3 the means 1b supplies power to the coil 2, and so that when the lamp is being lighted-up the means 1c supplies power to the coil 2. Therefore, optimum frequencies can be set when starting up the discharge lamp 3 and when keeping the lamp lighted-up resulting in the increased efficiency and miniaturization of a device.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrodeless discharge lamp lighting device for applying high frequency power to an electrodeless discharge lamp to emit light.

[0002]

2. Description of the Related Art Conventionally, an electrodeless discharge lamp lighting device of this type which applies high-frequency power to an electrodeless discharge lamp to emit light is shown in FIG.
As shown in the block diagram, a power supplier 11a that outputs high-frequency power, a high-frequency power supply coil 2 connected between the output ends of the power supply means 1a, and a high-frequency power supply coil 2 are arranged in proximity to each other. For example, a glass bulb is provided with an electrodeless discharge lamp 3 in which a discharge gas such as an inert gas or a metal vapor is sealed, and the high frequency power output from the power supply means 1a is supplied to the high frequency power supply. By supplying the high-frequency power supply coil 2 with a high-frequency electric field, a high-frequency electromagnetic field is generated in the high-frequency power supply coil 2, and the energy thereof excites the discharge gas inside the electrodeless discharge lamp 3 to generate a high-frequency plasma current, thereby generating ultraviolet rays The electrodeless discharge lamp 3 is discharged and emits light by generating visible light.

The operation will be briefly described below with reference to Table 1 and FIG. Table 1 shows the power required for the electrodeless discharge lamp 3 corresponding to the frequency of the electrodeless discharge lamp 3 to shift from glow discharge to arc discharge (hereinafter referred to as start-up) (hereinafter referred to as start-up power). Value) and the value of the minimum power (hereinafter, referred to as the minimum lighting maintenance power) required for the electrodeless discharge lamp 3 to maintain the arc discharge (hereinafter, referred to as the lighting maintenance) with respect to the frequency. 7 and based on the values shown in Table 1.
7A shows the relationship between the lighting frequency of the electrodeless discharge lamp 3 and the starting power, and FIG. 7B shows the relationship between the lighting frequency of the electrodeless discharge lamp 3 and the minimum lighting maintenance power. Here, Table 1 and FIG.
As shown in (a) and (b), the frequency is inversely proportional to the starting power or the minimum lighting maintenance power.

[0004]

[Table 1]

In FIG. 7, when the output power of the power supply means 1a is smaller than y (W) (10 <y <15), the lighting frequency of the electrodeless discharge lamp 3 is x (MHz) (3 <x). <
4) By selecting a large frequency, that is, by selecting a frequency of the electrodeless discharge lamp 3 (= frequency of the power supply means 1a) such that the starting power becomes smaller than the minimum lighting maintenance power, the power supply means The output power of 1a may be the rated power when the electrodeless discharge lamp 3 is turned on, and it is not necessary to consider the starting time.

Generally, from the viewpoint of the luminous efficiency of the electrodeless discharge lamp 3, the frequency of the power supply means 1a is preferably 1 MHz or higher, and when the lighting frequency of the electrodeless discharge lamp 3 becomes 5 MHz or higher, the power supply means 1a is newly amplified. Circuits are required and circuit efficiency is reduced. On the other hand, since a high-speed MOSFET is used for the power supply means 1a, the frequency of the power supply means 1a is preferably 1 to 3 (<x) MHz in order to obtain high circuit efficiency. In other words, it is desirable that the frequency of the power supply means 1a be 1 to 3 (<x) MHz when the electrodeless discharge lamp 3 is kept lit.

[0007]

However, in the conventional example, when the lighting frequency of the electrodeless discharge lamp 3 is lower than x (MHz), the minimum lighting sustaining voltage is higher than the minimum lighting sustaining voltage when the electrodeless discharge lamp 3 is started. Since it is necessary to supply a high starting voltage to the high frequency power supply coil 2 from the power supply means 1a, the power supply means 1a needs to use a component with large power consumption, which means high cost and large size of the device. The problem arises.

The present invention has been made in view of the above problems, and an object of the present invention is to set an optimum frequency at the time of starting and maintaining lighting of an electrodeless discharge lamp, and to improve the efficiency of the apparatus and An object of the present invention is to provide an electrodeless discharge lamp lighting device that can be downsized.

[0009]

In order to solve the above problems, according to the invention as set forth in claim 1, an electrodeless discharge lamp in which a discharge gas is enclosed in a bulb and a proximity to the electrodeless discharge lamp are provided. In the electrodeless discharge lamp lighting device, which is provided with a high-frequency power supply coil that supplies high-frequency power to the electrodeless discharge lamp by supplying a high-frequency current, the power necessary for starting the electrodeless discharge lamp is supplied. First power supply means for supplying a high frequency power supply coil and operating at a high frequency,
A second power supply that supplies the power necessary for maintaining the lighting of the electrodeless discharge lamp to the high frequency power supply coil and that operates at a low frequency
And a means for controlling the electrodeless discharge lamp from a starting state to a lighting state by switching the output from the first power supplying means to the second power supplying means. .

According to the second aspect of the invention, the electrodeless discharge lamp in which the discharge gas is enclosed in the bulb and the electrodeless discharge lamp are arranged in proximity to the electrodeless discharge lamp, and the electrodeless discharge lamp is formed by passing a high frequency current. In an electrodeless discharge lamp lighting device equipped with a high-frequency power supply coil for supplying high-frequency power, a low power required to maintain lighting of the electrodeless discharge lamp is supplied to the high-frequency power supply coil, and at the same time, at a high frequency. First power supply means for operating, high power necessary for maintaining lighting of the electrodeless discharge lamp is supplied to the high frequency power supply coil, and second power supply means for operating at a low frequency, and first power supply It is characterized in that a means for controlling the dimming of the electrodeless discharge lamp is provided by alternately switching the outputs of the supply means and the second power supply means.

[0011]

According to the invention described in claim 1, by operating the first power supply means at a high frequency (for example, 13.56 MHz), the power required for starting the electrodeless discharge lamp is supplied to the high frequency power supply coil. To start the electrodeless discharge lamp, and after the electrodeless discharge lamp is turned on, the first power supply means is switched to the second power supply means, and the second power supply means is operated at a low frequency (for example, 2. By operating at 65 MHz), the power required for lighting the electrodeless discharge lamp is supplied to the high frequency power supply coil to maintain the lighting of the electrodeless discharge lamp.

According to the second aspect of the present invention, by operating the first power supply means at a high frequency (for example, 13.56 MHz), the low power required for maintaining the lighting of the electrodeless discharge lamp is supplied as the high frequency power. And a second power supply means is operated at a low frequency (for example, 2.65 MHz) to supply high power necessary for maintaining the lighting of the electrodeless discharge lamp, and the first power supply means The dimming control of the electrodeless discharge lamp is performed by alternately switching the output with the second power supply means.

[0013]

【Example】

(Embodiment 1) FIG. 1 is a block diagram showing a first embodiment according to the present invention. The difference from the conventional example shown in FIG. 6 is that instead of the power supply means 1a in the conventional example, high frequency power is used. A sufficient power for starting the electrodeless discharge lamp 3 is supplied to the supply coil 2, and a high frequency (for example, 13.56M) is supplied.
Power supply means 1b having a frequency (Hz) and high-frequency power supply coil 2 are supplied with a rated power sufficient to maintain lighting of the electrodeless discharge lamp 3, and a low frequency (for example, 2.65 MH).
z) is provided, and by switching the switching element SW ₁ , the power supply means 1b supplies power to the high-frequency power supply coil 2 at the time of starting the electrodeless discharge lamp 3, and the electrodeless discharge lamp ₁ is discharged. When the electric light 3 is turned on, the power supply means 1
c is to supply electric power to the high frequency power supply coil 2, and the same reference numerals are given to the same configurations as the other conventional examples, and the description thereof will be omitted.

FIG. 2 shows a concrete circuit example of the power supply means 1b. The power supply means 1b includes a DC power source E and an oscillation circuit 4
, Amplifying units 5 and 8, filter circuit 6, and matching circuit 7
The oscillator circuit 4 is a circuit using a crystal oscillator X, and has a low Q due to the coil L ₆ and the capacitor C _15.
The tuning circuit is configured as an unadjusted oscillator.

The amplifiers 5 and 8 further include a first amplifier circuit (preamplifier) 5 for amplifying the oscillation output of the oscillator circuit 4 and a second amplifier circuit (main amplifier) for further high frequency power amplification of the output of the preamplifier 5. ) 8 and. Here, the preamplifier 5 performs class C amplification by the transistor Q ₄ , and tunes to the oscillation frequency by the coil L ₅ and the capacitor C ₁₇ . Further, the resistors R _{8 to} R _{10 form} an attenuator, and the resistor R ₁₁ is included to lower the Q of the coil L ₅ .

The main amplifier 8 is a power MOSFET
It is an amplifier based on Q ₅ (hereinafter referred to as a transistor). Coil L ₇ is included to cancel the input capacitance of transistor Q ₅ , and resistor R ₁₂ is included to match the input impedance of transistor Q ₅ with the output of preamplifier 5.

The filter circuit 6 is composed of a coil L ₃ , a capacitor C _4, etc., and prevents a high frequency from returning to the power source E. The matching circuit 7 has a capacitor C ₁₉ , C _20.
Is provided between the output of the main amplifier 8 and the electrodeless discharge lamp 3 and the high-frequency power supply coil 2 in the subsequent stage, the impedances of both are matched, and the electrodeless discharge lamp 3 is provided with no reflection. Impedance matching is performed so as to efficiently transmit high frequency power.

The operation of the power supply means 1b will be briefly described below. When receiving the DC voltage from the DC power supply E, the oscillation circuit 4 starts to oscillate, the signal of the oscillation circuit 4 is transmitted to the preamplifier 5 for amplification, and the amplified signal is transmitted to the main amplifier 8 for further amplification. . The high frequency voltage amplified by the main amplifier 8 is applied to the high frequency power supply coil 2, and a high frequency current is passed through the high frequency power supply coil 2 to generate high frequency power in the high frequency power supply coil 2 to generate no electrode. High frequency power is supplied to the discharge lamp 3 to generate high frequency plasma current in the electrodeless discharge lamp 3 to generate ultraviolet rays or visible light.

Next, FIG. 3 shows a concrete circuit example of the power supply means 1c. Power supply unit 1c Ji励Ha --bridge type inverter - a motor unit, which converts the DC power source E to the high-frequency AC power by alternating on and off of the transistors Q _6, Q ₈ is supplied to the load circuit 16 Is.

Here, the series circuit of the transistor Q ₆ and the transistor Q ₈ is connected to both ends of the DC power source E, and the diode D is connected between the collector and the emitter of the transistor Q _6.
3 is connected in anti-parallel. A diode D ₄ is connected in anti-parallel between the collector and the emitter of the transistor Q ₈ , and a series circuit of the primary winding n ₁ of the transformer T and the load circuit 16 is connected. The load circuit 16 is composed of a capacitor C ₂₂ for cutting a DC component, a series circuit of a load Ld including a coil 2 for high frequency power supply and an electrodeless discharge lamp 3, and a capacitor C ₂₃ connected in parallel to the load Ld. To be done. The transformer T includes a pair of secondary windings n ₂₁ ,
comprising a n _22, 2 One end of winding n ₂₁ are commonly connected to one end of the primary winding n _1, the other end base - scan resistor R ₁₃ of the transistor Q ₆ through the base - is connected to the scan It In addition, the secondary winding n
One end of ₂₂ is connected to the negative electrode of the DC power source E, the other end is connected to the base of the transistor Q ₈ via the base resistor R _14, and the starting circuit 17 is also connected.

The starting circuit 17 is connected to both ends of the DC power source E.
Resistance R₁₅And capacitor C_{twenty one}Series circuit consisting of
And the resistance R₁₅And capacitor C_{twenty one}One end at the connection point 18 with
Is connected and the other end is a transistor Q₈Connected to the base
Trigger element Q such as diac₇Composed of and
The resistance R when the DC power supply E is connected.₁₅Via con
Densa C_{twenty one}Charge the capacitor C_{twenty one}The voltage across
Moth element Q₇Trigger element when the breakover voltage of
Q₇Is turned on, the transistor Q₈Base
Current through the transistor Q₈Turn on. Also,
Anti-R₁₅And capacitor C_{twenty one}A diode is connected to the connection point 18 with
D_FiveThe node of is connected and the diode D _FiveThe cathedral
Is diode D₃And diode D_FourConnect to connection point 19 with
Has been continued.

With this configuration, the optimum frequency can be set for starting the electrodeless discharge lamp and for maintaining the lighting, and the efficiency and size of the device can be increased.

(Embodiment 2) FIG. 4 is a block diagram showing a second embodiment according to the present invention. The difference from the first embodiment shown in FIG. 1 is that the power supply means in the first embodiment is different. In place of 1b, the minimum lighting maintenance power of the electrodeless discharge lamp 3 is supplied, and a power supply means 1d having a high frequency (for example, 13.56 MHz) is provided to switch the switching element SW.
By switching ₁ to time division, the power supply means 1c and the power supply means 1d can alternately supply power to the high frequency power supply coil 2 when the electrodeless discharge lamp 3 is turned on. The same components as those in the example are designated by the same reference numerals and the description thereof will be omitted.

The operation will be briefly described below with reference to the operation waveform chart shown in FIG. Since the frequency of the power supply means 1c is smaller than that of the power supply means 1d, the output of the power supply means 1c is larger than that of the power supply means 1d as compared with FIG. The light output when the discharge lamp 3 is turned on is the power supply means 1
Due to d, the light output becomes larger than the light output when the electrodeless discharge lamp 3 is lit. Therefore, the dimming of the electrodeless discharge lamp 3 can be easily performed by switching the switching element SW ₁ in a time-division manner during the cycle of the frequency z (Hz) (for example, 100 Hz). The specific circuit example of the power supply means 1d may be the same as that shown in FIG.

[0025]

According to the first aspect of the present invention, an electrodeless discharge capable of setting an optimum frequency at the time of starting and maintaining lighting of the electrodeless discharge lamp and capable of achieving high efficiency and downsizing of the device. An electric lighting device can be provided.

According to the second aspect of the present invention, the optimum frequency for dimming control of the electrodeless discharge lamp can be set, and
It is possible to provide an electrodeless discharge lamp lighting device capable of achieving high efficiency and downsizing of the device.

[Brief description of drawings]

FIG. 1 is a block diagram showing a first embodiment according to the present invention.

FIG. 2 is a circuit diagram showing a specific example of a first power supply means according to the above embodiment.

FIG. 3 is a circuit diagram showing a specific example of a second power supply means according to the above embodiment.

FIG. 4 is a block diagram showing a second embodiment according to the present invention.

FIG. 5 is a diagram showing operation waveforms according to the above embodiment.

FIG. 6 is a block diagram showing a conventional example according to the present invention.

FIG. 7 is a diagram showing frequency-power characteristics according to the conventional example.

[Explanation of symbols]

 1 Power Supply Means 2 High Frequency Power Supply Coil 3 Electrodeless Lamp SW Switching Element

Claims (2)

[Claims] 1. An electrodeless discharge lamp in which a discharge gas is sealed in a bulb, and a high frequency wave which is disposed close to the electrodeless discharge lamp and supplies high frequency power to the electrodeless discharge lamp by supplying a high frequency current. In an electrodeless discharge lamp lighting device including a power supply coil, first power for supplying a power necessary for starting the electrodeless discharge lamp to the high frequency power supply coil and operating at a high frequency. Supplying means, second power supply means for supplying power necessary for maintaining lighting of the electrodeless discharge lamp to the high-frequency power supply coil, and operating at a low frequency, and the first power supply means An electrodeless discharge lamp lighting device, comprising means for controlling the electrodeless discharge lamp from a starting state to a lighting state by switching an output to a second power supply means. 2. An electrodeless discharge lamp in which a discharge gas is sealed in a bulb, and a high frequency device which is arranged close to the electrodeless discharge lamp and supplies a high frequency current to the electrodeless discharge lamp by supplying a high frequency current. In an electrodeless discharge lamp lighting device including a power supply coil, a low power required for maintaining lighting of the electrodeless discharge lamp is supplied to the high frequency power supply coil and operated at a high frequency. Power supply means, high power necessary for maintaining lighting of the electrodeless discharge lamp to the high frequency power supply coil, second power supply means operating at a low frequency, and the first power supply. An electrodeless discharge lamp lighting device, characterized by further comprising means for performing dimming control of the electrodeless discharge lamp by alternately switching the outputs of the means and the second power supply means.