JP2001093685A - Electrodeless discharge lamp lighting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrodeless discharge lamp lighting device, capable of reducing the restriction of the space between a matching circuit and a case and accurately adjusting the input impedance of the matching circuit. SOLUTION: A matching circuit 31 has a first constant variable element 10a, connected to a first terminal La of a solenoid L and a stable potential point 7 and a second constant variable element 10b connected to the stable potential point 7. Since the stable potential point 7 is grounded to a case (not shown) by way of a condenser C having a low impedance, the potential difference between first and second constant variable elements 10a and 10b and the case can be reduced, the restriction of the space between them can be reduced, and the input impedance of the matching circuit 31 can be adjusted accurately.

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 which emits light by applying a high frequency electromagnetic field to an electrodeless discharge lamp.

[0002]

2. Description of the Related Art An electrodeless discharge lamp lighting device shown in FIG. 8 is conventionally known (see Japanese Patent Application Laid-Open No. 9-35883).

This electrodeless discharge lamp lighting device is composed of a high-frequency oscillation circuit 4 for generating high-frequency power and a light-transmitting material for filling a discharge gas (for example, mercury or a rare gas) such as an inert gas or a metal vapor. Matching for matching the impedance of the electrodeless discharge lamp 1, the solenoid L, which is a high-frequency electromagnetic field applying means disposed closely along the outer circumference of the electrodeless discharge lamp 1, and the impedance of the electrodeless discharge lamp 1, the solenoid L, and the high-frequency oscillation circuit 4 And a high-frequency power generated by the high-frequency oscillation circuit 4.
Through the solenoid L, the discharge gas is excited and emits light by applying a high-frequency electromagnetic field to the discharge gas sealed in the electrodeless discharge lamp 1. The matching circuit 3 includes a coaxial cable 2 connected to one end of the high-frequency oscillation circuit 4 and a first terminal La of the solenoid L.
0b, a coaxial cable 20a connected to the other end of the high-frequency oscillation circuit 4, a first constant variable element Ca having a capacitive impedance, connected to the coaxial cable 20a and the second terminal Lb of the solenoid L, Coaxial cable 20
a, 20b and a second constant variable element Cb having a capacitive impedance, and a constant fixed element C connected in parallel with the solenoid L and having a capacitive impedance.
0.

Such an electrodeless discharge lamp lighting device has features such as small size, high output, and long life. Therefore, research and development have been conducted in various places, and various uses as a high output point light source are considered. ing.

However, in order to increase the luminous efficiency when the electrodeless discharge lamp 1 is turned on, the resistance components of the solenoid L and the matching circuit 3 are made very small, and the power consumed by the solenoid L and the matching circuit 3 is reduced. As a result, when the electrodeless discharge lamp 1 is started, the solenoid L and the matching circuit 3 serving as loads on the high-frequency oscillation circuit 4 have a very high Q state. In such a high Q state, the influence of the variation of the inductance value of the solenoid L and the variation of the constituent elements of the matching circuit 3 becomes very large, and particularly, the high-frequency oscillation circuit 4 when starting the electrodeless discharge lamp 1. Thus, there is a problem in that the variation of the input impedance becomes extremely large, and the output of the high-frequency oscillation circuit 4 fluctuates greatly.

In order to solve such a problem, the matching circuit 3 includes first and second constant variable elements Ca and Cb.
Is provided, and the variation of the input impedance is suppressed by adjusting the respective constants.

[0007]

However, since the constant variable element is generally larger than the fixed constant element, when the constant variable element is used, the constant variable element is insulated from other elements or at least from the housing housing the matching circuit. It becomes difficult to secure the distance, and this places great restrictions on the board design such as the layout of the printed circuit board on which the matching circuit 3 is mounted.

Further, the first and second constant variable elements C
When adjusting the constants a and Cb, it is necessary to bring a close body such as a human body or an adjustment jig close to the first and second constant variable elements Ca and Cb. The input impedance of the circuit 3 is adjusted. Therefore, after the proximity object is moved away, the adjustment of the input impedance of the matching circuit 3 is shifted, resulting in a problem that a large output fluctuation of the high-frequency oscillation circuit 4 cannot be eliminated.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems, and at least reduce the restriction on the distance between the housing housing the matching circuit and the matching circuit, and accurately adjust the input impedance of the matching circuit. An electrodeless discharge lamp lighting device is provided.

[0010]

In order to achieve the above object, the present invention is directed to an electrodeless discharge lamp made of a light-transmissive material in which a discharge gas is sealed, and a high-frequency electromagnetic discharge lamp for the electrodeless discharge lamp. High-frequency electromagnetic field applying means for applying an electric field, a high-frequency oscillation circuit for generating high-frequency power to be supplied to the electrodeless discharge lamp via the high-frequency electromagnetic field applying means, an electrodeless discharge lamp, a high-frequency electromagnetic field applying means, and a high-frequency oscillation circuit An electrodeless discharge lamp lighting device comprising: a matching circuit for matching the impedance of the discharge lamp; and a housing accommodating at least the matching circuit, wherein the matching circuit includes a stable potential point connected to the housing and the ground with low impedance. And a first constant variable element connected to a first terminal of the high-frequency electromagnetic field applying means, and a second constant variable element connected to a stable potential point. By connecting the first and second constant variable elements to a stable potential point and reducing the potential difference between the first and second constant variable elements and the housing, the first and second constant variable elements are reduced. The restriction on the distance between the element and the housing can be reduced, the degree of freedom of the layout of the matching circuit can be increased, and the first and second constants can be varied even when a small operating voltage is applied. The influence on the impedance by the human body or the adjustment jig for adjusting the element constant can be reduced, and the input impedance of the matching circuit can be adjusted accurately.

According to a second aspect of the present invention, in the first aspect, the matching circuit includes a π-type circuit, and the first constant variable element is connected to one of the elements constituting the π-type circuit or to the π-type circuit. It is characterized by being connected in series with the high-frequency electromagnetic field applying means, and by using a π-type circuit for which a detailed design method has been established for the matching circuit,
A matching circuit can be designed under optimal conditions.

According to a third aspect of the present invention, in the first aspect, the matching circuit includes a T-type circuit, and the first constant variable element is connected to one of the elements constituting the T-type circuit or to the T-type circuit. It is characterized by being connected in series to the high-frequency electromagnetic field applying means, and using a T-type circuit for which a detailed design method has been established for the matching circuit,
A matching circuit can be designed under optimal conditions.

According to a fourth aspect of the present invention, in any one of the first to third aspects of the invention, the first and second constant variable elements have a capacitive impedance, and use a capacitive element. Thereby, the constants of the first and second constant variable elements can be easily adjusted.

According to a fifth aspect of the present invention, in any one of the first to third aspects, the first and second constant variable elements have an inductive impedance, and use an inductive element. This increases the degree of freedom in designing the matching circuit, and as a result, the matching circuit can be configured with a small number of elements.

According to a sixth aspect of the present invention, in any one of the first to fifth aspects of the present invention, the high-frequency electromagnetic field applying means is a solenoid. Power can be supplied.

According to a seventh aspect of the present invention, in the sixth aspect, the solenoid is wound around the outside of the electrodeless discharge lamp, and the solenoid is disposed outside the electrodeless discharge lamp. Thereby, the structure of the electrodeless discharge lamp can be simplified.

According to an eighth aspect of the present invention, in the sixth aspect of the present invention, the solenoid is wound in a recess provided in the electrodeless discharge lamp, so that light is not blocked by the solenoid. , Can emit more light.

In a ninth aspect of the present invention, in any one of the first to eighth aspects, the sign of the imaginary part of the impedance of the first constant variable element is the same as the sign of the imaginary part of the impedance of the high-frequency electromagnetic field applying means. A constant fixed element, which is different and has substantially the same impedance as the first constant variable element, is connected to the second terminal of the high-frequency electromagnetic field applying means. The potential difference between the terminal and the stable potential point can be reduced.

According to a tenth aspect of the present invention, there is provided an electrodeless discharge lamp made of a light-transmissive material in which a discharge gas is sealed, and a high-frequency electromagnetic field applied to the electrodeless discharge lamp wound around the electrodeless discharge lamp. A high-frequency oscillation circuit that generates high-frequency power to be supplied to the electrodeless discharge lamp via the solenoid, a matching circuit that matches the impedance of the electrodeless discharge lamp, the solenoid, and the high-frequency oscillation circuit, and at least a matching circuit. An electrodeless discharge lamp lighting device comprising: a matching circuit;
A first constant variable element having a capacitive impedance connected to a stable potential point connected to the housing and the ground with a low impedance and a first terminal of the solenoid; and an inductive impedance connected to the stable potential point and connected to the stable potential point And a second constant variable element having a constant potential difference between the first and second constant variable elements and the housing by connecting the first and second constant variable elements to a stable potential point. , The restriction on the distance between the first and second constant variable elements and the housing can be reduced, the degree of freedom in the layout of the matching circuit can be increased, and the minute operating voltage can be reduced. Even when added, the influence on the impedance by the human body or the adjustment jig for adjusting the constants of the first and second constant variable elements can be reduced, and the input impedance of the matching circuit can be accurately adjusted. It can be an integer. Further, by using a solenoid as a high-frequency electromagnetic field applying means, a large amount of power can be supplied to the electrodeless discharge lamp, and since the solenoid is disposed outside the electrodeless discharge lamp, The structure can be simplified.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (Embodiment 1) The basic configuration in this embodiment is common to that of the conventional example. Only parts will be described in detail.

As shown in FIG. 1, the electrodeless discharge lamp lighting device of the present embodiment comprises a high-frequency oscillation circuit 4 and a matching circuit 3
1 are connected by one coaxial cable 2. The outer conductor 2b of the coaxial cable 2 is connected to a stable potential point 7 grounded to a casing (not shown) via a low impedance capacitor C.

The matching circuit 31 is connected to the outer conductor 2b of the coaxial cable 2 and the first terminal La of the solenoid L and has a first constant variable element 10a having a capacitive impedance, and the outer conductor 2b of the coaxial cable 2 A second constant variable element 10b connected to the second terminal Lb of the solenoid L and having an inductive impedance; and an inductor L1 connected to the core wire 2a of the coaxial cable 2 and the first terminal La of the solenoid L. And a capacitor C1 connected to the second terminal Lb of the solenoid L.

As described above, by connecting the first and second constant variable elements 10a and 10b to the stable potential point 7,
The potential difference between the first and second constant variable elements 10a and 10b and the housing can be reduced. As a result, the restriction on the distance between the first and second constant variable elements 10a and 10b and the housing can be reduced, and the degree of freedom in the layout of the printed circuit board on which the matching circuit 31 is mounted can be increased. Furthermore, even when a small operating voltage is applied,
Since the influence on the impedance of the human body or the adjustment jig for adjusting the constants of the first and second constant variable elements 10a and 10b can be reduced, the input impedance of the matching circuit 31 can be accurately adjusted.

Further, since the solenoid L is used as the high frequency electromagnetic field applying means, the electrodeless discharge lamp 1 can be used.
In addition, a large amount of power can be supplied to the electrodeless discharge lamp 1, and the structure of the electrodeless discharge lamp 1 can be simplified by winding the solenoid L outside the electrodeless discharge lamp 1.

If the electrodeless discharge lamp 1 is provided with a concave portion 1a as shown in FIG. 2 and the solenoid L is wound inside the concave portion 1a, the light is not blocked by the solenoid L, and the light is further reduced. There is an advantage that a large amount can be released. (Embodiment 2) Since the basic configuration in this embodiment is common to Embodiment 1, the same reference numerals are given to the common parts, and the description thereof will be omitted, and only the characteristic parts of this embodiment will be described in detail. I do.

The matching circuit 33 of the present embodiment is similar to that of FIG.
As shown in FIG. 5, a first constant variable element 12a connected to the outer conductor 2b of the coaxial cable 2 and the first terminal La of the solenoid L and having a capacitive impedance, a core 2a of the coaxial cable 2 and the solenoid L A second constant variable having a capacitive impedance, which is connected to a series circuit of the inductor L5 and the capacitor C2 connected to the second terminal Lb, and to a connection point between the inductor L5 and the capacitor C2 and the outer conductor 2b of the coaxial cable 2. A series circuit of an inductor L5 and a capacitor C2;
And a constant variable element 12b form a T-shaped circuit. Further, the impedance of the first constant variable element 12a and the capacitor C2 is determined by the capacitor C2 that can optimally light the electrodeless discharge lamp 1 when the matching circuit 33 does not include the first constant variable element 12a. Is a value obtained by substantially dividing the impedance value into two.

In this embodiment, the matching circuit 33
However, the matching circuit 33 can be designed under optimal conditions since it has a T-type circuit for which a detailed design technique has been established. Further, the first and second constant variable elements 12a,
Since 12b has a capacitive impedance, the constant can be easily adjusted. Further, the first constant variable element 12a and the capacitor C2, whose impedance values are substantially equal to each other and whose sign of the imaginary part of the impedance is different from that of the solenoid L, are connected to both ends of the solenoid L, respectively. First and second
The potential difference between the terminals La and Lb of the above and the stable potential point 7 can be reduced. (Embodiment 3) Since the basic configuration in this embodiment is common to Embodiment 1 or 2, the same reference numerals are given to the common parts, and the description thereof will be omitted, and only the characteristic parts of this embodiment will be described in detail. Will be described.

The matching circuit 35 of the present embodiment is similar to that of FIG.
, A first constant variable element 14a connected to the outer conductor 2b of the coaxial cable 2 and the first terminal La of the solenoid L and having a capacitive impedance, a core wire 2a of the coaxial cable 2 and the outer conductor 2b. , A second constant variable element 14b having a capacitive impedance,
The capacitor C4 is connected to the core wire 2a of the coaxial cable 2 and the second terminal Lb of the solenoid L, and the capacitor C5 is connected in parallel to the solenoid L. The second constant variable element 14b and the capacitors C4 and C5 A π-shaped circuit is formed. Furthermore, the impedance of the first constant variable element 14a and the capacitor C4 is determined by the capacitor C4 that can optimally light the electrodeless discharge lamp 1 when the matching circuit 35 does not include the first constant variable element 14a. Is a value obtained by substantially dividing the impedance value into two.

In the present embodiment, the matching circuit 35
However, since a π-type circuit having a detailed design method is established, the matching circuit 35 can be designed under optimal conditions. Also, as in the second embodiment, the first and second constant variable elements 14a and 14b have a capacitive impedance, so that the constants can be easily adjusted, and the impedance values are substantially equal to each other. Since the first constant variable element 14a and the capacitor C4 whose imaginary parts have different signs from the solenoid L are connected to both ends of the solenoid L, respectively, the first and second terminals La and Lb of the solenoid L are stable. The potential difference with the potential point 7 can be reduced. (Embodiment 4) Since the basic configuration in this embodiment is common to the conventional example, the same reference numerals are given to the common parts and the description thereof will be omitted, and only the characteristic parts of this embodiment will be described in detail. .

In the electrodeless discharge lamp lighting device of the present embodiment,
As shown in FIG. 5, one end of the high-frequency oscillation circuit 4 is connected via a low-impedance capacitor C to a stable potential point 7 that is grounded to a casing (not shown).

The matching circuit 34 is a T-type circuit 34a
And a capacitor C3 connected in parallel to the solenoid L. The T-type circuit 34a has one end connected to the stable potential point 7 of the high-frequency oscillation circuit 4 and the first terminal L of the solenoid L.
a, a first constant variable element 13a having an inductive impedance, and an inductor L connected to the other end of the high-frequency oscillation circuit 4 and a second terminal Lb of the solenoid L.
6 and L7, and a second constant variable element 13b connected to the connection point between the inductors L6 and L7 and the stable potential point 7 and having an inductive impedance. The inductors L6 and L7 and the second constant A T-shaped circuit is formed from the variable element 13b. Note that the first constant variable element 13a
When the matching circuit 34 does not include the first constant variable element 13a, the impedance of the inductor L7 that can optimally light the electrodeless discharge lamp 1 is approximately equal to two. It is desirable to set the value.

In the present embodiment, as in the second embodiment, the matching circuit 34 uses a T
Since the shape circuit is provided, the matching circuit 34 can be designed under optimum conditions. Furthermore, since the first and second constant variable elements 13a and 13b each have inductive impedance, the degree of freedom in designing the matching circuit 34 is increased, and as a result, the matching circuit 34 can be configured with a small number of elements. Can be configured. (Embodiment 5) Since the basic configuration in this embodiment is common to Embodiment 4, the same parts are denoted by the same reference numerals and the description thereof will be omitted, and only the characteristic parts of this embodiment will be described in detail. I do.

In the electrodeless discharge lamp lighting device of the present embodiment,
As shown in FIG. 6, the first terminal La of the solenoid L is
It is connected via a low-impedance capacitor C to a stable potential point 7 grounded to a housing (not shown).

The matching circuit 36 includes a high-frequency oscillation circuit 4
And a capacitor C7 connected to one end of the solenoid L and a second terminal Lb of the solenoid L, and a first constant variable having an inductive impedance connected to the other end of the high-frequency oscillation circuit 4 and the first terminal La of the solenoid L. Element 15a and capacitor C6
And an inductor L8 connected to a connection point between the capacitor C7 and the second terminal Lb of the solenoid L and a connection point between the high-frequency oscillation circuit 4 and the capacitor C6, and a capacitive impedance connected in parallel to the solenoid L. And a second constant variable element 15b. The π-type circuit 36a is formed by the first and second constant variable elements 15a and 15b, the capacitor C6, and the inductor L8,
The first constant variable element 15a and the capacitor C6 are adjusted by adjusting the inductance value of the constant variable element 15a.
Are variable.

In this embodiment as well, like the first to fourth embodiments, the first and second constant variable elements 15
By connecting a and 15b to the stable potential point 7, the potential difference between the first and second constant variable elements 15a and 15b and the housing can be reduced. As a result, restrictions on the distance between the first and second constant variable elements 15a and 15b and the housing can be reduced, and the degree of freedom in the layout of the printed circuit board on which the matching circuit 36 is mounted can be increased. Furthermore, even when a very small operating voltage is applied, the influence on the impedance of the human body or the adjustment jig for adjusting the constants of the first and second constant variable elements 15a and 15b can be reduced. The input impedance can be adjusted accurately. Embodiment 3
Similarly to the above, the matching circuit 36 includes the π-type circuit 36a for which a detailed design method has been established, so that the matching circuit 36 can be designed under optimum conditions. (Embodiment 6) The electrodeless discharge lamp lighting device of this embodiment is
As shown in FIG. 7, an electrodeless discharge lamp 1 made of a light-transmissive material filled with a discharge gas, and a high-frequency device that is disposed close to the electrodeless discharge lamp 1 with a high-frequency electromagnetic field applied to the electrodeless discharge lamp 1 A pair of electrodes 6a and 6b serving as an electromagnetic field applying means
And the electrodeless discharge lamp 1 via a pair of electrodes 6a and 6b.
A high-frequency oscillation circuit 4 for generating high-frequency power to be supplied to the
A matching circuit 32 for matching the impedance between the electrodeless discharge lamp 1 and the electrodes 6a, 6b and the high-frequency oscillation circuit 4.
And the coaxial cable 2 connecting the high-frequency oscillation circuit 4 and the matching circuit 32. The electrode 6a
Is connected to a stable potential point 7 grounded to a housing (not shown) via a low impedance capacitor C.

The matching circuit 32 is connected to the outer conductor 2b and the electrode 6a of the coaxial cable 2 and has a first constant variable element 11a having a capacitive impedance, and an inductor connected in parallel to the first constant variable element 11a. L4,
A series circuit of inductors L2 and L3 connected to the core wire 2a of the coaxial cable 2 and the electrode 6b;
And a second constant variable element 11b connected to the electrode 6a and having a capacitive impedance. The inductors L2 and L3 and the second constant variable element 11b
A shaped circuit is formed. Then, by adjusting the capacitance of the first constant variable element 11a, the combined impedance of the first constant variable element 11a and the inductor L4 is made variable.

In this embodiment as well, like the first to fifth embodiments, the first and second constant variable elements 11
a, 11b are connected to the stable potential point 7,
In addition, the potential difference between the second constant variable elements 11a and 11b and the housing can be reduced. As a result, the first and second
Can be reduced, and the degree of freedom of the layout of the printed circuit board on which the matching circuit 32 is mounted can be increased. Further, when a very small operating voltage is applied, the first
In addition, since the influence on the impedance of the human body or the adjustment jig for adjusting the constants of the second constant variable elements 11a and 11b can be reduced, the input impedance of the matching circuit 32 can be adjusted accurately. Further, as in the second or fourth embodiment, the matching circuit 32 includes a T-type circuit for which a detailed design method has been established, so that the matching circuit 32 can be designed under optimum conditions.

[0038]

According to the first aspect of the present invention, there is provided an electrodeless discharge lamp made of a light-transmissive material in which a discharge gas is sealed, a high-frequency electromagnetic field applying means for applying a high-frequency electromagnetic field to the electrodeless discharge lamp, A high-frequency oscillation circuit that generates high-frequency power to be supplied to the electrodeless discharge lamp via the electromagnetic field applying means, a matching circuit that matches the impedance of the electrodeless discharge lamp and the high-frequency electromagnetic field applying means and the high-frequency oscillation circuit,
An electrodeless discharge lamp lighting device comprising at least a housing for accommodating a matching circuit, wherein the matching circuit comprises a stable potential point connected to the housing and the ground with low impedance and a first high-frequency electromagnetic field applying means. The first connected to the terminal
And the second constant variable element connected to the stable potential point, the first and second constant variable elements are connected to the stable potential point, and the first and second constant variable elements are connected. By reducing the potential difference between the variable element and the casing, the restriction on the distance between the first and second constant variable elements and the casing can be reduced, and the degree of freedom in the layout of the matching circuit can be increased. In addition to this, even when a small operating voltage is applied, the influence on the impedance of the human body and the adjustment jig for adjusting the constants of the first and second constant variable elements can be reduced, and the input impedance of the matching circuit can be accurately adjusted. There is an effect that can be adjusted.

According to a second aspect of the present invention, the matching circuit includes a π-type circuit, and the first constant variable element is one of elements constituting the π-type circuit or an element connected to the π-type circuit,
In addition, since the π-type circuit for which the detailed design method has been established is used for the matching circuit because it is connected in series to the high-frequency electromagnetic field applying means, there is an effect that the matching circuit can be designed under optimum conditions.

According to a third aspect of the present invention, the matching circuit includes a T-type circuit, and the first constant variable element is one of elements constituting the T-type circuit or an element connected to the T-type circuit.
In addition, since the T-circuit is connected in series to the high-frequency electromagnetic field applying means, the matching circuit can be designed under optimal conditions by using a T-type circuit for which a detailed design method has been established as the matching circuit.

According to a fourth aspect of the present invention, the first and second constant variable elements have a capacitive impedance,
Further, there is an effect that the constant of the second constant variable element can be easily adjusted.

According to the fifth aspect of the present invention, since the first and second constant variable elements have inductive impedance, the degree of freedom in designing the matching circuit is increased, and as a result, the matching circuit can be formed with a small number of elements. There is an effect that it can be configured.

According to the sixth aspect of the present invention, since the high-frequency electromagnetic field applying means is a solenoid, there is an effect that a large amount of power can be supplied to the electrodeless discharge lamp.

According to the seventh aspect of the present invention, since the solenoid is wound outside the electrodeless discharge lamp, the structure of the electrodeless discharge lamp can be simplified.

According to the eighth aspect of the present invention, since the solenoid is wound in a concave portion provided in the electrodeless discharge lamp,
There is an effect that light is not blocked by the solenoid and more light can be emitted.

According to a ninth aspect of the present invention, the sign of the imaginary part of the impedance of the first constant variable element is different from the sign of the imaginary part of the impedance of the high-frequency electromagnetic field applying means.
Since the constant fixed element having substantially the same impedance as the first constant variable element is connected to the second terminal of the high frequency electromagnetic field applying means, the first and second constant frequency elements of the high frequency electromagnetic field applying means are connected.
There is an effect that the potential difference between the terminal and the stable potential point can be reduced.

According to a tenth aspect of the present invention, there is provided an electrodeless discharge lamp made of a light-transmissive material in which a discharge gas is sealed, and a high-frequency electromagnetic field applied to the electrodeless discharge lamp wound around the electrodeless discharge lamp. A high-frequency oscillation circuit that generates high-frequency power to be supplied to the electrodeless discharge lamp via the solenoid, a matching circuit that matches the impedance of the electrodeless discharge lamp, the solenoid, and the high-frequency oscillation circuit, and at least a matching circuit. An electrodeless discharge lamp lighting device comprising: a matching circuit;
A first constant variable element having a capacitive impedance connected to a stable potential point connected to the housing and the ground with a low impedance and a first terminal of the solenoid; and an inductive impedance connected to the stable potential point and connected to the stable potential point The first and second constant variable elements are connected to a stable potential point to reduce the potential difference between the first and second constant variable elements and the housing. Thereby, the restriction on the distance between the first and second constant variable elements and the housing can be reduced, the degree of freedom of the layout of the matching circuit can be increased, and when a small operating voltage is applied. However, it is possible to reduce the influence on the impedance by the human body or the adjusting jig for adjusting the constants of the first and second constant variable elements, and to accurately adjust the input impedance of the matching circuit. Can. Further, by using a solenoid as a high-frequency electromagnetic field applying means, a large amount of power can be supplied to the electrodeless discharge lamp, and since the solenoid is disposed outside the electrodeless discharge lamp, There is an effect that the structure can be simplified.

[Brief description of the drawings]

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

FIG. 2 is a sectional view showing another example of the electrodeless discharge lamp of the above.

FIG. 3 is a circuit diagram showing a second embodiment.

FIG. 4 is a circuit diagram showing a third embodiment.

FIG. 5 is a circuit diagram showing a fourth embodiment.

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

FIG. 7 is a circuit diagram showing a sixth embodiment.

FIG. 8 is a circuit diagram showing a conventional example.

[Explanation of symbols]

 Reference Signs List 1 electrodeless discharge lamp 2 coaxial cable 4 high-frequency oscillation circuit 7 stable potential point 10a, 10b constant variable element L solenoid

Claims (10)

[Claims] 1. An electrodeless discharge lamp made of a translucent material with a discharge gas sealed therein, a high-frequency electromagnetic field applying means for applying a high-frequency electromagnetic field to the electrodeless discharge lamp, and a high-frequency electromagnetic field applying means. A high-frequency oscillation circuit that generates high-frequency power to be supplied to the electrodeless discharge lamp; a matching circuit that matches the impedance of the electrodeless discharge lamp, the high-frequency electromagnetic field applying means, and the high-frequency oscillation circuit; and a housing that houses at least the matching circuit. Wherein the matching circuit comprises: a stable potential point connected to the housing and the ground with low impedance; and a first constant connected to the first terminal of the high-frequency electromagnetic field applying means. A variable element,
An electrodeless discharge lamp lighting device, comprising: a second constant variable element connected to a stable potential point. 2. A matching circuit comprising a π-type circuit,
2. The device according to claim 1, wherein the constant variable element is one of elements constituting a π-shaped circuit or an element connected to the π-shaped circuit, and is connected in series to a high-frequency electromagnetic field applying means. Electrodeless discharge lamp lighting device. 3. A matching circuit comprising a T-shaped circuit,
2. The device according to claim 1, wherein the constant variable element is one of elements constituting a T-shaped circuit or an element connected to the T-shaped circuit, and is connected in series to a high-frequency electromagnetic field applying means. Electrodeless discharge lamp lighting device. 4. The apparatus according to claim 1, wherein the first and second constant variable elements have a capacitive impedance.
3. The electrodeless discharge lamp lighting device according to claim 1. 5. The device according to claim 1, wherein the first and second constant variable elements have an inductive impedance.
3. The electrodeless discharge lamp lighting device according to claim 1. 6. The electrodeless discharge lamp lighting device according to claim 1, wherein the high-frequency electromagnetic field applying means is a solenoid. 7. The electrodeless discharge lamp lighting device according to claim 6, wherein the solenoid is wound around the electrodeless discharge lamp. 8. The electrodeless discharge lamp lighting device according to claim 6, wherein the solenoid is wound in a recess provided in the electrodeless discharge lamp. 9. The fixed constant having the sign of the imaginary part of the impedance of the first constant variable element different from the sign of the imaginary part of the impedance of the high-frequency electromagnetic field applying means and having substantially the same impedance as the first constant variable element. The element is
9. The electrodeless discharge lamp lighting device according to claim 1, wherein the electrodeless discharge lamp lighting device is connected to a second terminal of the high-frequency electromagnetic field applying means. 10. An electrodeless discharge lamp comprising a light-transmissive material filled with a discharge gas therein, a solenoid wound around the electrodeless discharge lamp and applying a high-frequency electromagnetic field to the electrodeless discharge lamp, and a solenoid. A high-frequency oscillation circuit that generates high-frequency power to be supplied to the electrodeless discharge lamp through the electrodeless lamp, a matching circuit that matches the impedance of the electrodeless discharge lamp, the solenoid, and the high-frequency oscillation circuit, and a housing that houses at least the matching circuit. An electrodeless discharge lamp lighting device comprising: a matching circuit connected to a first terminal of a solenoid and a stable potential point connected to the housing and the ground with a low impedance; and a first circuit having a capacitive impedance. A variable constant element connected to a stable potential point and having a second constant variable element having an inductive impedance. Electrodeless discharge lamp lighting device.