JPH0729549A - Variable color discharge lamp device - Google Patents

Abstract

(57) [Summary] [Object] To provide a variable color discharge lamp device in which the luminous efficiency of a discharge lamp is improved. [Structure] Main electrodes 2a and 2b are provided in both ends in a direction along a center line of a straight tube-shaped bulb 1, respectively. Auxiliary electrodes 3a and 3b made of thin film conductors are provided on the outer surface of the bulb 1 so as to face each other with the surface including the center line interposed therebetween. A fluorescent layer 4 coated with a fluorescent substance is formed on the inner peripheral surface of the bulb wall of the bulb 1. The bulb 1 is filled with mercury vapor and a rare gas as light emitting gases. An AC voltage is applied to both main electrodes 2a and 2b by the main lighting device 5. Further, the auxiliary lighting device 6 applies an AC voltage to both the auxiliary electrodes 3a and 3b. An inductor 7 is inserted and connected in series between the auxiliary electrode 3b and the auxiliary lighting device 6. A resonance circuit is configured by the auxiliary electrodes 3a and 3b and the inductor 7. Since the resonance frequency of this resonance circuit is made substantially equal to the frequency of the auxiliary lighting device 6, the power factor at the auxiliary electrodes 3a and 3b can be improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a variable color discharge lamp device capable of color matching using a discharge lamp which utilizes the luminescence of a fluorescent substance such as a fluorescent lamp.

[0002]

2. Description of the Related Art Conventionally, as a variable color discharge lamp device having a variable emission color, as shown in FIG.
A fluorescent layer 4 coated with a fluorescent substance is formed on the inner wall thereof, and two types of light emitting gas (for example, a rare gas and a mercury vapor) are enclosed, and a pair of main electrodes 2a,
A pair of auxiliary electrodes 3a and 3b formed of a transparent material on the tube wall of the bulb 1 are provided so as to be spaced apart from each other and face each other.
Are provided so as to face each other, and the light emitted from the mercury vapor ionized and excited by the discharge generated by applying the AC voltage from the main lighting device 5 to the main electrodes 2a and 2b is converted into visible light by the fluorescent substance. , A rare gas that is ionized and excited by a negative glow discharge generated by applying an AC voltage from the auxiliary lighting device 6 to the auxiliary electrodes 3a and 3b emits visible light having a frequency different from the frequency of visible light generated by the fluorescent material, There is a variable color discharge lamp device capable of adjusting the color of mixed color light by adjusting the applied voltage of at least one of the main lighting device 5 and the auxiliary lighting device 6.

[0003]

However, the above structure has a problem that the luminous efficiency of the discharge lamp A is low because the power factor in the negative glow discharge between the auxiliary electrodes 3a and 3b is poor. Furthermore, in order to obtain sufficient brightness from the portion where the negative glow is generated between the auxiliary electrodes 3a and 3b,
There is a problem in that it is necessary to apply a high voltage between a and 3b, a component with a high breakdown voltage must be used, the device becomes large, and the efficiency of the lighting device deteriorates.

An object of the present invention is to solve the above problems and to provide a variable color discharge lamp device in which the power factor in a negative glow discharge between auxiliary electrodes is improved to improve the luminous efficiency of a discharge lamp. Is what you are trying to do.

[0005]

In order to achieve the above object, the invention of claim 1 has at least a pair of main electrodes for discharge which are arranged so as to be longer than the length of the negative glow. And at least one kind of first light emitting gas that emits light that is ionized and excited by the discharge between the main electrodes and that is converted into visible light by the fluorescent substance, as well as negative ionization A discharge lamp having a bulb filled with at least one second light-emitting gas that is excited to emit visible light having a wavelength different from that of the fluorescent substance, and discharges by applying a voltage between the main electrodes. A main lighting device for generating an electric current, at least a pair of auxiliary electrodes, an auxiliary lighting device for applying an AC voltage between the auxiliary electrodes to generate a discharge between the auxiliary electrodes, and an auxiliary electrode inserted into at least one of the auxiliary electrodes. The main lighting device and the auxiliary lighting device, at least one of the applied voltage and the frequency can be adjusted, and the frequency of the AC voltage applied between the auxiliary lighting device and the auxiliary electrode is adjusted between the auxiliary electrodes. It is characterized in that the frequency is close to the resonance frequency determined by the equivalent electrostatic capacitance between the auxiliary electrodes and the inductance of the inductor when a negative glow discharge is generated.

The invention of claim 2 is characterized in that, in the invention of claim 1, the inductance of the inductor is variable. The invention of claim 3 is characterized in that, in the invention of claims 1 and 2, a capacitor is connected in parallel between the auxiliary electrodes. The invention of claim 4 is characterized in that, in the inventions of claims 1 to 3, the capacitance of the capacitor is variable.

[0007] The invention of claim 5 is defined by claims 1 to 4.
In the invention, the bulb is tubular, and the main electrodes are arranged so as to face each other in the direction along the center line of the bulb, and at least a pair of auxiliary electrodes different from the main electrode are sandwiched across the plane including the center line of the bulb. It is characterized in that the electrodes are separated from each other by a distance shorter than the length of the portion where the negative glow is generated between the electrodes and are opposed to each other.

[0008]

According to the structure of the first aspect of the present invention, at least a pair of main electrodes for discharge which are spaced apart from each other so as to be longer than the length of the negative glow are provided, and a fluorescent substance is built in between the main electrodes. Is different from visible light from a fluorescent substance that is ionized and excited in a negative glow and at least one first light-emitting gas that emits light that is ionized and excited by the discharge of the fluorescent substance and is converted into visible light by the fluorescent substance. A discharge lamp having a bulb filled with at least one kind of second light emitting gas that emits visible light of a wavelength, a main lighting device that applies a voltage between main electrodes to generate a discharge, and at least a pair of auxiliary devices The main lighting device and the auxiliary lighting device are provided with electrodes, an auxiliary lighting device that applies an AC voltage between the auxiliary electrodes to generate a discharge between the auxiliary electrodes, and an inductor that is inserted into at least one of the auxiliary electrodes. At least one of the applied voltage and the frequency can be adjusted, and the frequency of the AC voltage applied between the auxiliary lighting device and the auxiliary electrode is adjusted by the auxiliary electrode when a negative glow discharge occurs between the auxiliary electrodes. Since the frequency is close to the resonance frequency determined by the equivalent electrostatic capacitance between the inductor and the inductance of the inductor, the imaginary component of the impedance of the discharge lamp seen from the auxiliary lighting device during lighting of the discharge lamp becomes substantially zero, It is possible to improve the power factor of the auxiliary electrode and improve the luminous efficiency of the discharge lamp.

According to the second aspect of the invention, since the inductance of the inductor is variable, the resonance frequency can be changed so as to be substantially equal to the frequency of the AC voltage applied from the auxiliary lighting device. In the configuration of the invention of claim 3, since the capacitors are connected in parallel between the auxiliary electrodes,
The resonance frequency between the auxiliary electrodes can be changed.

According to the structure of the fourth aspect of the invention, since the capacitance of the capacitor is variable, the resonance frequency can be changed so as to be substantially equal to the frequency of the AC voltage applied from the auxiliary lighting device. According to a fifth aspect of the invention, the bulb is tubular and the main electrodes are arranged so as to face each other in the direction along the center line of the bulb, and at least a pair of auxiliary electrodes other than the main electrode includes the center line of the bulb. Since the main electrodes are separated by a distance shorter than the length of the portion where the negative glow occurs between the main electrodes and are arranged so as to face each other, the emission color can be made variable in the discharge lamp having the tubular bulb.

[0011]

【Example】

(Embodiment 1) In this embodiment, as shown in FIG. 1, main electrodes 2a and 2b are provided in both ends of the straight tube-shaped valve 1 in the direction along the center line, and the outer surface of the valve 1 has the above-mentioned structure. The auxiliary electrodes 3a, 3 are arranged so as to face each other with the surface including the center line interposed therebetween.
The discharge lamp A is constructed by providing b. Here, the auxiliary electrodes 3a and 3b are formed by attaching a thin film conductor to the outer peripheral surface of the tube wall of the bulb 1.

Further, a fluorescent layer 4 coated with a fluorescent substance is formed on the inner peripheral surface of the bulb wall of the bulb 1, and mercury vapor and a rare gas as light emitting gases are enclosed in the bulb 1. An AC voltage is applied to both of the main electrodes 2a and 2b by a main lighting device 5 that is capable of adjusting at least one of the output voltage and the frequency while outputting the AC voltage, and the AC voltage is applied to both of the auxiliary electrodes 3a and 3b. The AC voltage is applied by the auxiliary lighting device 6 that outputs. Further, an inductor 7 is inserted and connected in series between the auxiliary electrode 3b and the auxiliary lighting device 6.

In the above structure, when an AC voltage is applied to the main electrodes 2a, 2b and the auxiliary electrodes 3a, 3b, negative glow occurs near the negative electrode at each time of the main electrode and the auxiliary electrode. However, since the distance between the main electrodes 2a and 2b is set to be sufficiently longer than the length of the negative glow generated by the discharge between both electrodes, the mercury vapor in the positive column portion generated between the main electrodes 2a and 2b. Is ionized and excited to generate ultraviolet rays, which are converted into visible rays by the fluorescent layer 4 to generate a light output outside the bulb 1. For example, a phosphor mainly containing halophosphorus calcium emits white visible light.

On the other hand, by setting the distance between the auxiliary electrodes 3a and 3b shorter than the length of the portion where the negative glow is generated between the main electrodes 2a and 2b, almost only the negative glow is generated between the auxiliary electrodes 3a and 3b. Is to occur. Inside the negative glow, the rare gas is ionized and excited to emit light, and the light output of the emission color peculiar to the type of the rare gas is generated from the portion where the negative glow is generated. If, for example, neon is selected as the rare gas, a reddish emission color is obtained from the site where the negative glow occurs. In short, the emission color mainly due to the luminescence of the fluorescent layer 4 is obtained at the portion where the positive column between the main electrodes 2a and 2b is generated, and the emission color is mainly obtained at the portion where the negative glow is generated between the auxiliary electrodes 3a and 3b. Moreover, the emission color from the rare gas can be obtained. That is, by selecting both emission colors so as to be different from each other, it is possible to obtain an emission color different from both the emission colors of the negative glow and the fluorescent layer 4 as the mixed color light, and the output voltage of the main lighting device 5 or The emission color can be continuously changed by adjusting the frequency.

By the way, the inventor of the present application equivalently connected a series circuit of a resistor 8 (resistance value R) and a capacitor 9 (capacitance C) as shown in FIG. 2 between the auxiliary electrodes 3a and 3b. I found that can be represented by. Therefore, a resonance circuit is formed by the inductor 7 connected to the auxiliary electrode 3b and the capacitor 9, and the resonance frequency fc of this resonance circuit is determined by the inductance L of the inductor 7 and the capacitance C of the capacitor 9, and its value is several. It is represented by the formula shown by 1.

[0016]

[Equation 1]

Then, the resonance frequency fc determined by the above equation 1
The value of the inductance L of the inductor 7 is set so that the value of is close to the frequency of the AC voltage output from the auxiliary lighting device 6. Therefore, since the imaginary number component of the impedance when the auxiliary lighting device 6 is viewed from the auxiliary electrodes 3a and 3b during discharge becomes substantially equal to zero, the auxiliary electrodes 3a and 3b
The power factor between 3b can be improved, and the luminous efficiency can be improved. Further, since the voltage amplitude between the auxiliary electrodes 3a and 3b becomes large due to the resonance in the resonance circuit, it is not necessary to make the alternating voltage applied from the auxiliary lighting device 6 to the auxiliary electrodes 3a and 3b high voltage, and a component having high withstand voltage can be used. Even if it is not used, the completed device does not become large, and the efficiency of the lighting device does not deteriorate.

Although a cold cathode is used for the main electrode in this embodiment, a hot cathode may be used as shown in FIG. In short, if there is a discharge between the electrodes,
The technical idea of the present invention can be applied regardless of the shape or the like. (Embodiment 2) In this embodiment, as shown in FIG.
In addition to the above configuration, an inductor 10 is inserted and connected in series between the auxiliary electrode 3a and the auxiliary lighting device 6. Here, the inductances of the inductors 7 and 10 are respectively set to L ₁ and L
_{If 2} , then the resonance frequency f of the resonance circuit in this embodiment is
c is expressed by Equation 2.

[0019]

[Equation 2]

In the above configuration, the values of the inductances L ₁ and L ₂ of the inductors 7 and 10 are set so that the values are close to the frequency of the AC voltage output from the auxiliary lighting device 6. The other configurations and operations are the same as those in the first embodiment, and the description thereof will be omitted. (Embodiment 3) This embodiment is different from Embodiment 1 in the configuration of the auxiliary electrode. That is, as shown in FIG. 5, first auxiliary electrodes 3a and 3b formed by attaching conductors to the main electrode 2a side of the outer peripheral surface of the bulb 1 of the valve 1 and second auxiliary electrodes formed on the main electrode 2b side. The valve 1 is provided with 11a and 11b. Further, an AC voltage is applied to the first auxiliary electrodes 3a and 3b from the first auxiliary lighting device 6 and to the second auxiliary electrodes 11a and 11b from the second auxiliary lighting device 12, respectively. An inductor 7 is connected in series between the electrode 3b and the first auxiliary lighting device 6, and an inductor 10 is connected in series between the second auxiliary electrode 11b and the second auxiliary lighting device 12. The inductances of the inductors 7 and 10 are such that the resonance frequencies are close to the frequency of the AC voltage applied from the first auxiliary lighting device 6 and the frequency of the AC voltage applied from the second auxiliary lighting device 12, respectively. Is set to.

In the above structure, negative glow is generated between the first auxiliary electrodes 3a and 3b and between the second auxiliary electrodes 11a and 11b. Moreover, since the two pairs of auxiliary electrodes are provided in parallel with each other in the direction along the center line of the bulb 1 and an AC voltage is applied to each, the negative glow should be generated substantially uniformly in the direction along the center line of the bulb 1. You can The number of auxiliary electrodes may be increased more than in the present embodiment, and in that case, negative glow can be generated more uniformly. Other configurations and operations are the same as those in the first and second embodiments, and thus the description thereof will be omitted.

(Embodiment 4) In this embodiment, as shown in FIG. 6, the inductance of the inductor 7 in Embodiment 1 is variable. In the above configuration, the inductor 7 is responsive to the frequency of the AC voltage applied from the auxiliary lighting device 6.
By adjusting the value of the inductance of, the resonance frequency close to the frequency of the AC voltage can be obtained. Further, if the frequency of the AC voltage applied from the auxiliary lighting device 6 is kept constant and the inductance of the inductor 7 is changed, the resonance frequency changes, so the intensity of the negative glow discharge between the auxiliary electrodes 3a and 3b also changes. . That is, by changing the inductance of the inductor 7, the discharge lamp A
Can be dimmed. Other configurations and operations are the same as those in the first embodiment, and thus the description thereof will be omitted.

(Fifth Embodiment) In this embodiment, as shown in FIG. 7, a capacitor 13 is inserted between the auxiliary electrodes 3a and 3b in the first embodiment. Therefore, the auxiliary electrode 3
When the capacitance of the capacitor 13 inserted between a and 3b is C ₁ , the resonance frequency fc is expressed by equation 3.

[0024]

[Equation 3]

In the above structure, the capacitance value of the capacitor 13 may be appropriately selected so that the resonance frequency fc is close to the frequency of the AC voltage of the auxiliary lighting device 6. Other configurations and operations are the same as those in the first embodiment, and thus the description thereof will be omitted. (Embodiment 6) In this embodiment, as shown in FIG. 8, the capacitor 13 in the embodiment 5 is a variable capacitor 14. Therefore, assuming that the capacitance of the variable capacitor 14 inserted between the auxiliary electrodes 3a and 3b is C ₁ , the resonance frequency f
c ₁ is represented by Formula 4.

[0026]

[Equation 4]

FIG. 9 shows the auxiliary electrodes 3a,
The relationship between the resonance frequency of the resonance circuit including the equivalent capacitor C between 3b, the inductor 7 and the variable capacitor 14 inserted in the auxiliary lighting device 6, and the intensity of the negative glow emission between the auxiliary electrodes 3a and 3b is shown. The figure is shown. A point P in the figure shows a case where the capacity of the variable capacitor 14 is the above C ₁ . Next, when the capacitance of the variable capacitor 14 is increased from C ₁ to C ₂ , the resonance frequency fc ₂ of the resonance circuit is as shown in Formula 5.

[0028]

[Equation 5]

Therefore, the resonance frequency fc₂Is fc₁than
It becomes smaller (because C₁<C ₂), Auxiliary electrode 3
The intensity of the negative glow emission between a and 3b moves to point Q in FIG.
Move. Therefore, the alternating voltage applied from the auxiliary lighting device 6 is applied.
If the frequency of the flow voltage is constant, the variable capacitor 14
Decreasing the capacity reduces the intensity of negative glow emission.
You can do it. That is, the variable capacitor 14
Dimming the discharge lamp A by changing the capacity
Can be done.

Further, the above-mentioned light control means may be realized by making the inductor 7 variable as shown in the fourth embodiment without depending on the variable capacitor 14, and the inductor 7 having a variable inductance. Variable capacitor 14
May be realized by In addition, the above-mentioned first to sixth embodiments
In the case where the noble gas enclosed in the bulb 1 as the light emitting gas is, for example, xenon, by using two or more different kinds of phosphors in the phosphor layer 4, the visible light is converted into visible light by the ultraviolet rays emitted by mercury. It is possible to obtain a mixed emission color of two emission colors by making the emission color of the phosphor different from the emission color of the phosphor converted into visible light by the ultraviolet rays emitted by xenon. Further, the shape of the valve is not limited to the straight pipe shape, and may be an annular shape or a spherical shape.

[0031]

According to the first aspect of the present invention, at least a pair of main electrodes for discharge which are spaced apart from each other so as to be longer than the length of the negative glow are provided, and a fluorescent substance is incorporated between the main electrodes. Different from visible light from a fluorescent substance that is ionized and excited in at least one first light-emitting gas that emits light that is ionized and excited by the discharge of the fluorescent substance and converted into visible light by the fluorescent substance, and negative glow A discharge lamp having a bulb filled with at least one kind of second light emitting gas that emits visible light of a wavelength, a main lighting device that applies a voltage between main electrodes to generate a discharge, and at least a pair of auxiliary devices A main lighting device and an auxiliary lighting device, each of which includes an electrode, an auxiliary lighting device that applies an AC voltage between the auxiliary electrodes to generate a discharge between the auxiliary electrodes, and an inductor that is inserted into at least one of the auxiliary electrodes. At least one of the applied voltage and the frequency can be adjusted, and the frequency of the AC voltage applied between the auxiliary lighting device and the auxiliary electrodes can be adjusted between the auxiliary electrodes when a negative glow discharge occurs between the auxiliary electrodes. Since the frequency is close to the resonance frequency determined by the equivalent capacitance of the inductor and the inductance of the inductor, the imaginary component of the impedance on the discharge lamp side as seen from the auxiliary lighting device is approximately equal to zero, and the negative glow discharge at the auxiliary electrode Can improve the power factor of and improve the luminous efficiency of the discharge lamp,
As compared with the case where no inductor is added, there is an effect that the same amount of electric power can be supplied to the discharge lamp with a smaller current to improve the efficiency of the auxiliary lighting device. Further, the voltage between the auxiliary electrodes becomes higher than the voltage applied from the auxiliary lighting device due to resonance, and it is not necessary to make the output voltage of the auxiliary lighting device high, so the breakdown voltage of the elements and the like that make up the auxiliary lighting device can be kept low. The cost can be reduced.

According to the second aspect of the present invention, since the inductance of the inductor is variable, the resonance frequency is changed so as to be substantially equal to the frequency of the AC voltage applied from the auxiliary lighting device, and the discharge lamp is dimmed. There is an effect that can be. According to the invention of claim 3, since the capacitors are connected in parallel between the auxiliary electrodes, there is an effect that the resonance frequency between the auxiliary electrodes can be changed.

Since the capacity of the capacitor is variable, the resonance frequency can be changed so as to be substantially equal to the frequency of the AC voltage applied from the auxiliary lighting device, and the discharge lamp can be adjusted. It has the effect of being able to shine. According to a fifth aspect of the present invention, the bulb is tubular and the main electrodes are arranged so as to face each other in a direction along the center line of the bulb, and at least a pair of auxiliary electrodes different from the main electrode are provided on a surface including the center line of the bulb. Since the main electrodes are separated by a distance shorter than the length of the portion where the negative glow is generated between the main electrodes and are arranged to face each other, it is possible to change the emission color in a discharge lamp having a tubular bulb. .

[Brief description of drawings]

1A and 1B show Example 1, in which FIG. 1A is an overall schematic configuration diagram, and FIG. 1B is a side sectional view of a discharge lamp.

FIG. 2 is a diagram showing an equivalent circuit between the auxiliary electrodes of the same.

FIG. 3 is an overall schematic configuration diagram in which a main electrode is a cold cathode in the same as above.

FIG. 4 is an overall schematic configuration diagram showing a second embodiment.

FIG. 5 is an overall schematic configuration diagram showing a third embodiment.

6A and 6B show Example 4 in which FIG. 6A is an overall schematic configuration diagram, and FIG. 6B is a side sectional view of a discharge lamp.

FIG. 7 is an overall schematic configuration diagram showing a fifth embodiment.

FIG. 8 is an overall schematic configuration diagram showing a sixth embodiment.

FIG. 9 is a diagram showing the relationship between the resonance frequency and the intensity of negative glow emission as above.

FIG. 10 shows a conventional example, in which (a) is an overall schematic configuration diagram and (b) is a side sectional view of a discharge lamp.

[Explanation of symbols]

 A discharge lamp 1 bulb 2 main electrode 3 auxiliary electrode 4 fluorescent layer 5 main lighting device 6 auxiliary lighting device 7 inductor

Claims (5)

[Claims] 1. At least one pair of main electrodes for discharge, which are arranged so as to be longer than the length of the negative glow, are arranged apart from each other, and a fluorescent substance is contained therein to be ionized and excited by a discharge between the main electrodes. At least one first light-emitting gas that emits light that is converted into visible light by the fluorescent substance, and emits visible light having a wavelength different from that of the visible light emitted from the fluorescent substance by being ionized and excited in the negative glow. At least 1
A discharge lamp having a bulb filled with a second type of light emitting gas, a main lighting device for applying a voltage between the main electrodes to generate a discharge, at least a pair of auxiliary electrodes, and an AC voltage between the auxiliary electrodes. An auxiliary lighting device that applies a voltage to generate a discharge between the auxiliary electrodes, and an inductor that is inserted into at least one of the auxiliary electrodes, and at least one of the main lighting device and the auxiliary lighting device has an applied voltage and a frequency. The frequency of the AC voltage applied from the auxiliary lighting device to the auxiliary electrodes can be adjusted by adjusting at least one of them, and the equivalent capacitance between the auxiliary electrodes and the inductance of the inductor when negative glow discharge occurs between the auxiliary electrodes. A variable color discharge lamp device having a frequency close to a resonance frequency determined by. 2. The variable color discharge lamp device according to claim 1, wherein the inductance of the inductor is variable. 3. The variable color discharge lamp device according to claim 1, further comprising a capacitor connected in parallel between the auxiliary electrodes. 4. The variable color discharge lamp device according to claim 3, wherein the capacity of the capacitor is variable. 5. The valve has a tubular shape, and main electrodes are arranged so as to face each other in a direction along a center line of the valve, and at least a pair of auxiliary electrodes different from the main electrode are sandwiched across a surface including the center line of the valve. 5. The variable color discharge lamp device according to claim 1, wherein the variable color discharge lamp device is arranged such that the main electrodes are separated from each other by a distance shorter than a length of a portion where the negative glow is generated and are opposed to each other.