JP2002352771A - Discharge lamp device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a discharge lamp device, which reduces the effect of magnetic field on discharge of a discharge lamp, and reduces fluctuations in the position of a lightening point in the discharge lamp. SOLUTION: A discharge lamp device shown in Fig. 1 comprises a discharge lamp 3, a reflector 4, an outer case 5, and a cooling fun 6. The discharge lamp 3 is housed at a specified position inside the reflector 4. The outer case 5 is made into almost a rectangular shape and is composed of a magnetic shielding material. The reflector 4 is located in the outer case 5. Further, the cooling fun 6 is set to a rear member 15d of the outer case 5 outside the outer case 5. Since this makes the magnetic shielding material surround the discharge lamp 3, the magnetic field affecting the discharge lamp 3 is reduced. As a result, fluctuations in the position of the lightening point in the discharge lamp 3 can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a discharge lamp device utilizing a light emission phenomenon caused by a discharge generated between electrodes to which a voltage is applied.

[0002]

2. Description of the Related Art FIG. 16 is a perspective view schematically showing the structure of a conventional discharge lamp device. The conventional discharge lamp device shown in FIG. 16 is used as a light source of, for example, a projection display (a liquid crystal projector, a DLP projector, etc.). The conventional discharge lamp device includes a discharge lamp 3, a reflector (also referred to as a “reflecting mirror”) 4, an outer case 5, and a cooling fan 6.

[0003] The discharge lamp 3 includes a glass tube 1 whose central portion is swelled in a spherical shape, and rod-shaped electrodes 2a and 2b.
The rod-shaped electrodes 2a and 2b penetrate the glass tube 1, and one end of the electrode 2a and one end of the electrode 2b are arranged at a predetermined distance inside the spherical portion of the glass tube 1.

The reflector 4 has a substantially conical shape, and has an open bottom surface, and is made of, for example, heat-resistant glass. Then, at a predetermined position inside the reflector 4,
The discharge lamp 3 is arranged so that at least a spherical portion of the discharge lamp 3 is housed. In addition, outer box 5
Has a substantially rectangular parallelepiped shape, and an upper surface member 15a;
Lower surface member 15b, front member 15c, rear member 15d
And side members 15e and 15f. In addition, outer box 5
Are formed of a plastic material. The reflector 4 is disposed in the outer box 5 such that the open bottom surface and the front member 15c of the outer box 5 face each other. The front member 15c of the outer box 5 is opened with a size substantially equal to the opening diameter of the bottom surface of the reflector 4. A cooling fan 6 is attached to the rear surface member 15 d of the outer case 5 outside the outer case 5.

[0005] In the conventional discharge lamp device having the above-described structure, for example, high-pressure xenon gas is sealed inside the spherical portion of the glass tube 1 of the discharge lamp 3.
When a high voltage is applied between the electrodes 2a and 2b, an arc discharge occurs between the electrodes 2a and 2b. As a result, light is generated in the discharge lamp 3. This light is called "discharge light". The diffused discharge light is repeatedly reflected in the reflector 4 and is collected in one direction. The light collected by the reflector 4 is taken out from the opening of the outer box 5 and
The irradiation target is irradiated with the light. The cooling fan 6 cools the high temperature discharge lamp 3 and prevents the temperature of the discharge lamp 3 from rising.

[0006]

In the conventional discharge lamp device, when a magnetic field is applied to the discharge lamp 3, an electromagnetic force acts on the discharge lamp 3 according to Fleming's law. This electromagnetic force affects the arc discharge between the electrodes 2a and 2b of the discharge lamp 3. Specifically, an arc column, which is a light emitting region of the discharge lamp 3, is bent by the electromagnetic force, and the discharge position (mainly, the position where electrons reach) in the electrodes 2a and 2b may change. In some cases, the arc column was bent without changing the discharge position.
Here, strictly speaking, the light emitting area of the discharge lamp 3 is an area having a certain range, but the distance between the electrodes 2a and 2b of the discharge lamp 3 is about 1 mm to 13 mm.
The light emitting area is very small. Therefore, the light emitting area of the discharge lamp 3 is referred to as a “light emitting point”. That is, the electromagnetic force affects the discharge of the discharge lamp 3, and the position of the light emitting point in the discharge lamp 3 moves.

[0007] Since the discharge lamp device is used in various environments, depending on the environment in which the discharge lamp device is used, electronic devices may be arranged around the device. At that time, the magnetism of the magnetic field formed by the electronic device has the above-described effect on the discharge of the discharge lamp 3. Although not shown in FIG. 16, the discharge lamp device itself has various electric circuits, and the light emitting point of the discharge lamp 3 may move due to the magnetism of the magnetic field formed by the electric circuits. was there. The electric circuit of the discharge lamp device includes a power supply circuit for applying a high voltage to the electrodes 2a and 2b, a drive circuit for operating the cooling fan 6, and the like.

When the light emitting point of the discharge lamp 3 moves, the position of the light condensed by the reflector 4 also moves, and there is a problem that the irradiation target cannot be sufficiently irradiated with light. Further, when the intensity or direction of the magnetism affecting the discharge of the discharge lamp 3 changes, the position of the light emitting point also changes with the change in the magnetism. Therefore, the position of the light condensed by the reflector 4 also changes with the change in magnetism. As a result, the position of the light extracted from the discharge lamp device fluctuates, and the amount of light taken into the device using the light from the discharge lamp device fluctuates. This variation in the amount of light sometimes caused a failure in the device.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to reduce the magnetism affecting the discharge of a discharge lamp and reduce the fluctuation of the position of a light emitting point in the discharge lamp. It is intended to provide a device.

[0010]

Means for Solving the Problems Claim 1 of the present invention
The discharge lamp device described in (1) includes a discharge lamp, and magnetic reduction means for reducing magnetism affecting discharge in the discharge lamp.

According to a second aspect of the present invention, the discharge lamp device is the discharge lamp device according to the first aspect, wherein the magnetism reducing means is a magnetic shield disposed around the discharge lamp. That is the material.

According to a third aspect of the present invention, there is provided the discharge lamp device according to the first aspect, wherein the magnetism reducing means is a magnet, and a second magnet generated by the magnet is provided. The magnetic field acts in a direction to reduce the magnetic field.

According to a fourth aspect of the present invention, there is provided a discharge lamp device according to the third aspect, wherein the magnet is an electromagnet.

According to a fifth aspect of the present invention, there is provided a discharge lamp device according to the fourth aspect, wherein a plurality of the electromagnets are provided.

According to a sixth aspect of the present invention, there is provided a discharge lamp device according to any one of the fourth and fifth aspects, wherein the current supplied to the electromagnet is controlled. By doing, the second of the electromagnet
And current control means for changing the intensity of the magnetic field.

The discharge lamp device according to a seventh aspect of the present invention is the discharge lamp device according to the sixth aspect, further comprising a luminance sensor for detecting a luminance intensity of light generated from the discharge lamp. And the current control means changes the intensity of the second magnetism of the electromagnet based on a detection result from the luminance sensor.

According to another aspect of the present invention, there is provided a discharge lamp device according to the fifth aspect, wherein the electromagnet is operated by controlling a current supplied to each of the electromagnets. Is further provided.

The discharge lamp device according to a ninth aspect of the present invention is the discharge lamp device according to the eighth aspect, further comprising a luminance sensor for detecting a luminance intensity of light generated from the discharge lamp. And the current control means selects the electromagnet to be operated based on a detection result from the luminance sensor.

According to a tenth aspect of the present invention, there is provided the discharge lamp device according to the fifth aspect, wherein a current supplied to the electromagnet is controlled to thereby control the electric current of the electromagnet. And a current control means for reversing the direction of magnetism.

[0020] The discharge lamp device according to claim 11 of the present invention is the discharge lamp device according to claim 10, further comprising a luminance sensor for detecting the intensity of luminance of light generated from the discharge lamp. The current control means reverses the direction of the second magnetism of the electromagnet based on a detection result from the luminance sensor.

According to a twelfth aspect of the present invention, there is provided a discharge lamp device according to any one of the third and fourth aspects, wherein the position of the magnet is moved. Means are further provided.

The discharge lamp device according to a thirteenth aspect of the present invention is the discharge lamp device according to the twelfth aspect, further comprising a luminance sensor for detecting a luminance intensity of light generated from the discharge lamp. The moving means moves the position of the magnet based on the detection result of the luminance sensor.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 FIG. 1 is a perspective view schematically showing the structure of the discharge lamp device according to the first embodiment. FIG. 2 shows the discharge lamp device shown in FIG. 1 on the side from which light is extracted, that is, the arrow in FIG. It is a front view when seen from A1 side. As shown in FIGS. 1 and 2, the discharge lamp device according to the first embodiment includes a discharge lamp 3, a reflector 4, an outer case 5, and a cooling fan 6.

The discharge lamp 3 includes a glass tube 1 and rod-shaped electrodes 2a and 2b. The glass tube 1 has a spherical portion 1a and cylindrical portions 1b and 1c, and the inside of the spherical portion 1a is also hollow. The cylindrical portions 1b and 1c are arranged in a straight line in the longitudinal direction, and one end in the longitudinal direction of the cylindrical portion 1b and one end in the longitudinal direction of the cylindrical portion 1c are connected to the spherical portion 1a. I have. In other words, the glass tube 1
Has a shape in which a central portion of a cylindrical glass member is inflated into a spherical shape.

The rod-like electrodes 2 a and 2 b are arranged in a straight line in the longitudinal direction and penetrate the glass tube 1. Then, inside the spherical portion 1a of the glass tube 1, the end of the electrode 2a and the end of the electrode 2b face each other at a predetermined distance. In other words, the distance between the electrodes 2a and 2b is the predetermined distance.

The reflector 4 has a substantially conical shape, has an open bottom surface, and is made of, for example, heat-resistant glass. Then, at a predetermined position inside the reflector 4,
The discharge lamp 3 is arranged so that at least the spherical portion 1a of the discharge lamp 3 is housed. The outer box 5 has a substantially rectangular parallelepiped shape, and has an upper surface member 15a.
, Lower surface member 15b, front member 15c, and rear member 1
5d and side members 15e and 15f. And
Each member constituting the outer box 5 is formed of a magnetic shielding material, for example, soft magnetic iron (JIS C 2504). Further, as a magnetic shielding material, for example, a non-directional electromagnetic steel strip (JIS C 2552), a directional electromagnetic steel strip (JIS
C 2553), magnetic steel strip, steel plate for magnetic poles (JIS C
2555), iron-nickel alloys, ferrites, iron-aluminum alloys, iron-cobalt alloys, and amorphous high-permeability materials may be used. What is iron-aluminum alloy?
For example, permalloy (Fe-Ni containing 35 to 80% Ni)
Alloy), Isopalm (50% F formed by cold rolling)
e-Ni alloy), permbar (30% Fe, Ni:
45%, Co: 25% alloy), wherein the iron-aluminum alloy is, for example, alpalm, alfell, alphenol, and the iron-cobalt alloy is, for example, hyperco, permendur, amorphous. High-permeability material refers to F containing a metalloid such as B, P, or Si.
e, a magnetic alloy made of Ni, Co or the like, for example, Fe5Co70Si15B10, Fe3Co12P16
B6Al3, Fe40Ni40P14B6, Fe29N
i49P14B6Si2.

The reflector 4 is arranged in the outer case 5 such that the open bottom surface and the front member 15c of the outer case 5 face each other. And the front member 15 of the outer box 5
c has an opening at a position facing the bottom surface of the reflector 4 and having substantially the same size as the opening diameter of the bottom surface. A cooling fan 6 is attached to the rear surface member 15 d of the outer case 5 outside the outer case 5.

In the discharge lamp apparatus according to the first embodiment having the above-described structure, for example, high-pressure xenon gas is sealed in the spherical portion 1a of the glass tube 1 of the discharge lamp 3, and the electrode 2a , 2b, an arc discharge occurs between the electrodes 2a, 2b.
As a result, discharge light is generated in the discharge lamp 3. Then, the discharge light diffused from the light emitting point repeats reflection in the reflector 4 and is collected in one direction. Reflector 4
The light condensed by the light passes through the opening on the bottom surface of the reflector 4 and is taken out of the opening of the outer box 5 to irradiate the irradiation target with the light. The cooling fan 6 cools the high temperature discharge lamp 3 and prevents the temperature of the discharge lamp 3 from rising.

In the discharge lamp device according to the first embodiment, since the magnetic shielding material is used as the material of the outer box 5 surrounding the discharge lamp 3, magnetism generated outside the discharge lamp device (hereinafter, "external (Referred to as "magnetism") on the discharge lamp 3 can be reduced. In particular,
For example, when a magnetic field is generated from an electronic device arranged around the discharge lamp device and the external magnetism of the magnetic field acts in the direction indicated by the direction 30 of the external magnetism in FIG. Since the upper surface member 15a is formed of a magnetic shielding material, external magnetism is reduced in the discharge lamp device. Therefore, the movement of the light emitting point in the discharge lamp 3 can be reduced. As a result, it is possible to provide the system using the light extracted from the discharge lamp device according to the first embodiment with light with less fluctuation and stable irradiation direction.

Further, in the discharge lamp device shown in FIGS. 1 and 2, the magnetic shielding material is used for all members constituting the outer box 5, but if the direction of the external magnetism is known, only the members corresponding to the direction are used. In addition, by using a magnetic shielding material, the material cost of the discharge lamp device can be reduced.
FIG. 3 is a perspective view schematically showing the structure of a modified example of the discharge lamp device according to the first embodiment. The directions of the external magnetism 30x and 30 are measured by measuring with an existing magnetic sensor.
3 shows the structure when y is known. In the discharge lamp device shown in FIG.
The magnetic shielding material is used only for members located in the directions indicated by 0x and 30y, that is, only for the upper surface member 15a and the lower surface member 15b. Since the magnetic shielding material is generally more expensive than the plastic material, the material cost of the discharge lamp device can be reduced by using the magnetic shielding material only in a necessary minimum part.

The magnetic shielding material such as the above-mentioned electromagnetic soft iron reduces external magnetism, and does not always completely shield external magnetism.

Embodiment 2 FIG. FIG. 4 is a perspective view schematically showing the structure of the discharge lamp device according to the second embodiment. FIG. 5 shows the discharge lamp device shown in FIG. It is a front view when it sees from A2 side. In the discharge lamp device according to the first embodiment, the magnetic shielding material is arranged around the discharge lamp 3 as a means for reducing external magnetism affecting the discharge lamp 3. In the discharge lamp device, the magnet 10 is arranged around the discharge lamp 3 to reduce external magnetism.

As shown in FIGS. 4 and 5, the discharge lamp device according to the second embodiment includes a discharge lamp 3, a reflector 4, an outer box 5, a cooling fan 6, and a magnet 10. . The magnet 10 is, for example, a permanent magnet, is disposed inside the outer box 5, and is attached to a predetermined position of the side member 15 e of the outer box 5. The N pole of the magnet 10 is located on the lower surface member 15b side, and the S pole is located on the upper surface member 15a side. It should be noted that an electromagnet may be used as the magnet 10, in which case a predetermined current source is required. Further, a plastic material is used as a material of the outer box 5. Other structures are the same as those in the first embodiment.
And the description thereof is omitted.

In the discharge lamp device according to the second embodiment having the above-described structure, when the direction 30 of the external magnetism is known by the existing magnetic sensor, the direction opposite to the direction 30 of the external magnetism is used. The magnets 10 are arranged so as to generate magnetism in the outside, thereby reducing external magnetism. In particular,
As shown in FIG. 5, when the direction 30 of the external magnetism is from the upper surface member 15a of the outer box 5 to the lower surface member 15b, the N pole of the magnet 10 is on the lower surface member 15b side, and the S pole is on the upper surface member. It is arranged on the 15a side. Since the magnetic direction 20 from the magnet 10 is from the north pole to the south pole, in other words, is from the lower surface member 15b to the upper surface member 15a, the magnetic direction 20 of the magnet 10 is different from the external magnetic direction 30. It is the opposite direction. Therefore, external magnetism can be reduced by the magnet 10.

Further, in the discharge lamp device according to the first embodiment, in order to reduce external magnetism generated outside the discharge lamp device, a magnetic shielding material is used as the material of the outer case 5 and the discharge lamp 3 is used. The magnetic shielding material was arranged around the. Therefore, when a drive circuit or the like for operating the cooling fan 6 is disposed inside the outer box 5, the first embodiment
Then, the magnetism generated from the drive circuit, in other words,
The magnetism generated immediately near the discharge lamp 3 could not be reduced. In the discharge lamp device according to the second embodiment, the magnet 10 is used as means for reducing magnetism affecting the discharge of the discharge lamp 3, and the magnetism generated from the magnet 10 is actively used. The magnetism generated inside can also be reduced. Hereinafter, the term “external magnetism” includes magnetism generated in the discharge lamp device.

Further, in the discharge lamp device according to the second embodiment, since the outer case 5 is made of a plastic material that transmits magnetism well, for example, the outer surface of the outer case 5 is applied to the side surface material 15e. A magnet 10 may be attached.

Further, by using the magnetic shielding material used in the first embodiment instead of the plastic material as the material of the outer box 5, the external magnetism can be further reduced.

Embodiment 3 6 and 7 show the third embodiment.
8 is a perspective view and a side view schematically showing the structure of the discharge lamp device according to the first embodiment, and FIG. 8 is a sectional view taken along line A3-A3 in FIG. In the discharge lamp device according to the above-described second embodiment, the magnet 10 is fixed to the outer case 5 and cannot move, but the discharge lamp device according to the third embodiment includes the moving unit 100. Thus, the position of the magnet 10 can be moved. 6 and 7, the illustration of the outer box 5 is omitted.

As shown in FIGS. 6 to 8, the discharge lamp device according to the third embodiment includes a discharge lamp 3, a reflector 4, an outer case 5, a cooling fan 6, a magnet 10, and a moving unit 100. And The moving means 100 is, for example,
Magnet guides 11 and 12 and screws 16a and 16b are provided. The magnet guide 11 has a magnet fixing member 11a and a support member 11b. The magnet fixing member 11a is formed by forming a slender flat plate into a ring shape in the longitudinal direction, and has a groove 15a formed along the circumferential direction. The support member 11b is a rectangular parallelepiped, and one end in the longitudinal direction is connected to the magnet fixing member 11a.
The magnet 10 is mounted inside the magnet fixing member 11a. Specifically, a screw 16a is inserted into the groove 15a from outside the magnet fixing member 11a, and the magnet fixing member 11
A screw 16a is attached to the magnet 10 so as to sandwich “a”.

The magnet guide 12 is a rectangular flat plate, and has a groove 15b formed along its longitudinal direction. The other end of the magnet guide 11 in the longitudinal direction of the support member 11b is inserted into a groove 15b of the magnet guide 12, and a screw 16b is attached to the support member 11b so as to sandwich the magnet guide 12. As a result, the magnet guide 11 is fixed to the magnet guide 12. Here, the groove 15b of the magnet guide 12 extends along a direction perpendicular to a plane including the circumferential direction of the magnet fixing member 11a of the magnet guide 11.

The moving means 100 is disposed inside the outer box 5 and the magnet fixing member 1 of the magnet guide 11 is provided.
1a surrounds the side surface of the reflector 4. Here, the magnet 10 is located between the reflector 4 and the magnet fixing member 11 a of the magnet guide 11. The other structure is the same as that of the discharge lamp device according to the above-described second embodiment, and the description thereof is omitted.

Embodiment 3 having the structure as described above
In the discharge lamp device according to the above, as shown in FIG.
0 can move around the discharge lamp 3. Specifically, since the groove 15a is formed along the circumferential direction of the magnet fixing member 11a, the magnet fixing member 11a
The magnet 10 can be moved along the circumferential direction.
Since the magnet fixing member 11 a surrounds the side surface of the reflector 4 having the discharge lamp 3 therein, the magnet 10 can move around the discharge lamp 3.

Further, as shown in FIG.
In the discharge lamp device according to the above, the distance between the magnet 10 and the discharge lamp 3 can be changed. Specifically, the groove 15b of the magnet guide 12 extends along a direction perpendicular to a plane including the circumferential direction of the magnet fixing member 11a of the magnet guide 11. Therefore, by moving the support member 11b of the magnet guide 11 in the groove 15b of the magnet guide 12,
The position of the magnet guide 11 with respect to the discharge lamp 3 can be changed while the magnet guide 11 surrounds the side surface of the reflector 4. As a result, the distance between the magnet 10 and the discharge lamp 3 can be changed.

As described above, since the discharge lamp device according to the third embodiment includes the moving means 100, even when the direction of the external magnetic field changes, the direction of the external magnetic field is opposite to the direction of the external magnetic field. The magnet 10 can be moved so that the magnetism is generated. Therefore, even when the direction of the external magnetism changes, the external magnetism can be reduced.

Even when the intensity of external magnetism with respect to the discharge lamp 3 changes, the discharge lamp 3 and the magnet 10
Of the magnetic discharge lamp 3 generated from the magnet 10 in accordance with the strength of the external magnetic field
Can be varied. Therefore, even when the intensity of the external magnetism changes, the external magnetism can be reduced.

In the discharge lamp device according to the third embodiment, the magnet 10 is manually moved.
For example, by attaching a gear to the magnet 10 and the magnet guide 12 and providing a geared motor to the magnet guide 11, the magnet 10 can be moved electrically.

Embodiment 4 FIG. 9 is a front view schematically showing the structure of the discharge lamp device according to the fourth embodiment.
The discharge lamp device according to the fourth embodiment is the same as the discharge lamp device according to the second embodiment described above, except that the magnet 10 is an electromagnet and further includes a current control circuit 40 that controls a current supplied to the electromagnet. It is. Hereinafter, in the fourth embodiment, the magnet 10 is referred to as “electromagnet 10”.

As shown in FIG. 9, a current control circuit 40 is connected to the electromagnet 10. The current control circuit 40 changes the value of the current supplied to the electromagnet 10. When the value of the current supplied to the electromagnet 10 changes, the intensity of the magnetism generated therefrom also changes.
The intensity of the magnetism generated by the electromagnet 10 can be changed. For example, the current control circuit 40 includes a voltage source and a variable resistor, and the value of the current supplied to the electromagnet 10 can be changed by changing the value of the variable resistor. Other structures are described in the second embodiment.
And the description thereof is omitted.

Embodiment 4 having the above structure
Since the discharge lamp device according to the first aspect includes the current control circuit 40, the value of the current supplied to the electromagnet 10 can be changed by the current control circuit 40 when the intensity of the external magnetism changes. Therefore, the magnetic strength of the electromagnet 10 can be adjusted according to the change in the external magnetic strength. As a result, even when the intensity of the external magnetism changes, the external magnetism can be reliably reduced.

Embodiment 5 FIG. 10 is a sectional view schematically showing the structure of the discharge lamp device according to the fifth embodiment. The discharge lamp device according to the fifth embodiment is basically the same as that of the third embodiment described above, except that the magnet 10 is an electromagnet and a plurality of magnets are provided, and a current for controlling a current supplied to the electromagnet is provided. It further includes a control circuit 40. The magnet fixing ring 21 is formed by integrally forming the magnet guide 11 and the magnet guide 12 according to the third embodiment.

As shown in FIG. 10, magnets 10a to 10h
Is fixed inside the magnet fixing ring 21 and the magnet 1
0a and magnet 10e, magnet 10b and magnet 10f, magnet 10
c and the magnet 10g, and the magnet 10d and the magnet 10h are arranged to face each other. Hereinafter, in Embodiment 5 and Embodiments 6 and 7 described later, the magnets 10a to 10h are referred to as “electromagnets 10a to 10h”.

The current control circuit 40 includes the electromagnets 10a to 10a
h. In the current control circuit 40 according to the fourth embodiment, the intensity of the magnetism generated from the electromagnet 10 is changed by changing the value of the current supplied to the electromagnet 10. The control circuit 40 turns on / off the supply of current to each of the electromagnets 10a to 10h. That is, the current control circuit 40 can select the electromagnet to be operated among the electromagnets 10a to 10h. For other structures,
Since the third embodiment is the same as the third embodiment, the description thereof is omitted.

Embodiment 5 having the above-described structure
In the discharge lamp device according to the above, even when the direction of the external magnetism changes, the external magnetism can be reduced. Specifically, as shown in FIG. 10, when the external magnetism is acting in the direction indicated by the direction 30a of the external magnetism, it is necessary to generate the magnetism in the direction opposite to the direction 30a of the external magnetism. , The current control circuit 40 causes the electromagnet 10a
The supply of current to is turned ON, and the electromagnet 10a is operated. Then, when the direction in which the external magnetism acts changes to the direction indicated by the direction 30c of the external magnetism, the current control circuit 40 turns off the current supply to the electromagnet 10a,
In order to stop the electromagnet 10a and turn on the supply of current to the electromagnet 10c to operate the electromagnet 10c in order to generate magnetism in the direction opposite to the direction of the external magnetism 30c.
As described above, by selecting the electromagnet to be operated from the plurality of electromagnets by the current control circuit 40, the external magnetism can be reliably reduced even when the direction of the external magnetism changes. .

Note that the external magnetism is 30
When acting in both directions a and 30c, the external magnetism can be reliably reduced by operating the electromagnets 10a and 10c by the current control circuit 40. That is, the external magnetism can be reduced even with respect to composite external magnetism from multiple directions.

Embodiment 6 FIG. FIG. 11 is a sectional view schematically showing the structure of the discharge lamp device according to the sixth embodiment. The discharge lamp device according to the sixth embodiment differs from the discharge lamp device according to the fifth embodiment in that a function of reversing the direction of the current supplied to the electromagnet is added to the current control circuit 40. Due to the additional operation, the number of electromagnets in the sixth embodiment is reduced to half the number of electromagnets in the fifth embodiment.

As shown in FIG. 11, the discharge lamp device according to the sixth embodiment includes electromagnets 10a to 10d, and a current control circuit 40 is connected to each of the electromagnets 10a to 10d. The current control circuit 40 controls each electromagnet 1
The current supply to the electromagnets 10a to 10d is turned on / off, and the direction of the current supplied to the electromagnets 10a to 10d is reversed. Therefore, the current control circuit 40 controls the electromagnet 10
The direction of magnetism generated from a to 10d can be reversed. That is, one electromagnet can generate magnetism acting in directions opposite to each other. Other structures are the same as those of the discharge lamp device according to the above-described fifth embodiment, and a description thereof will be omitted.

Embodiment 6 having the structure as described above
In the discharge lamp device according to the fifth embodiment, the current control circuit 40 can generate magnetism acting in directions opposite to each other from one electromagnet. Therefore, the same number as the discharge lamp device according to the fifth embodiment can be achieved with a smaller number of electromagnets. The effect can be obtained. Specifically, as shown in FIG. 11, by operating the electromagnet 10c by the current control circuit 40, for example,
c, 20c 'can be generated. Here, the magnetic direction 20c 'indicates the same direction as the magnetic direction 20g generated from the electromagnet 10g arranged to face the electromagnet 10c provided in the fifth embodiment. That is, since the electromagnet 10c can generate magnetism in the same direction as the magnetism generated by the electromagnet 10g, the sixth embodiment does not need to include the electromagnet 10g. Similarly,
In the fifth embodiment, there is no need to include an electromagnet 10e arranged opposite to the electromagnet 10a, an electromagnet 10f arranged opposite to the electromagnet 10b, and an electromagnet 10h arranged opposite to the electromagnet 10d. as a result,
The discharge lamp device according to the sixth embodiment can achieve the same effect as the discharge lamp device according to the fifth embodiment with a smaller number of electromagnets.

Embodiment 7 FIG. FIG. 12 is a front view schematically showing the structure of the discharge lamp device according to the seventh embodiment. The discharge lamp device according to Embodiment 7 is the same as the discharge lamp device according to Embodiment 4 described above, further including a luminance sensor 50.

As shown in FIG. 12, the luminance sensor 50 is connected to the current control circuit 40. Then, the luminance sensor 50 detects the intensity of the luminance of the light extracted from the discharge lamp device, and sends the detection result to the current control circuit 40. The current control circuit 40 changes the value of the current supplied to the magnet 10 based on the detection result from the luminance sensor 50, and changes the strength of the magnetism generated from the magnet 10. Other structures are the same as those of the discharge lamp device according to the above-described fourth embodiment, and therefore, description thereof will be omitted.

Next, a method of reducing external magnetism in the discharge lamp device according to the seventh embodiment will be described in detail. The projection light 60a shown in FIG. 12 indicates light extracted from the discharge lamp device when the intensity of the external magnetism does not change and the external magnet is appropriately reduced by the electromagnet 10. Reference numeral 60b denotes light extracted from the discharge lamp device when the intensity of external magnetism changes or when the value of the current supplied to the electromagnet 10 is controlled by the current control circuit 40.

FIG. 13 is a diagram showing a luminance distribution of light extracted from the discharge lamp device, and FIG.
FIG. 13 is a diagram showing a luminance distribution of the projection light 60a, and FIG.
(B) is a diagram showing a luminance distribution of the projection light 60b.

First, the luminance sensor 50 detects the luminance of the projection light 60a when the external magnetism is appropriately reduced, and obtains the luminance value. Here, this luminance value is referred to as “initial luminance value”. Then, the luminance sensor 50 sends the initial luminance value to the current control circuit 40. Current control circuit 40
Stores an initial luminance value which is a detection result of the luminance sensor 50. In addition, since the external magnetism is appropriately reduced, the luminance sensor 50 at this time is located in the bright portion 70 as shown in FIG.

Next, the brightness sensor 50 detects the brightness of the projection light 60b when the intensity of the external magnetic field changes and the position of the light extracted from the discharge lamp device changes from the projection light 60a to the projection light 60b. Then, the luminance value is obtained. Here, this luminance value is referred to as “control luminance value”. Then, the luminance sensor 50 sends the control luminance value to the current control circuit 40. At this time, since the intensity of the external magnetism has changed, the reduction of the external magnetism by the electromagnet 10 does not work well, and the brightness sensor 50 is located in the dark portion 71 as shown in FIG. . That is, the control luminance value is smaller than the initial luminance value and does not become the same value. Current control circuit 40
Calculates the difference between the received control brightness value and the stored initial brightness value. If the difference is equal to or greater than a predetermined value, the electromagnet 1
By changing the value of the current supplied to 0, the intensity of the magnetism generated from the electromagnet 10 is changed. Then, the luminance sensor 50 detects the luminance of the projection light 60b extracted from the discharge lamp device again, obtains a control luminance value, and sends the control luminance value to the current control circuit 40. Then, the current control circuit 40 calculates a difference between the received control luminance value and the initial luminance value, and if the difference is equal to or less than a predetermined value, that is, if the reduction of the external magnetism is appropriately performed, the electromagnet 10 Is held, and if the current is equal to or greater than the predetermined value, the above operation is repeated.

As described above, in the discharge lamp device according to the seventh embodiment, based on the detection result of the luminance sensor 50,
Since the magnetic strength of the electromagnet 10 is changed, the magnetic strength of the electromagnet 10 can be automatically adjusted optimally even when the external magnetic strength changes. for that reason,
Even if the change in the strength of the external magnetism is unknown, the external magnetism can be reliably reduced.

It is to be noted that the discharge lamp devices according to the fifth and sixth embodiments further include a luminance sensor 50 so that the external magnetism can be reliably reduced even if the change in the direction of the external magnetism is unknown. Can be. FIG. 14 is a cross-sectional view schematically showing a structure when the discharge lamp device according to the fifth embodiment further includes a luminance sensor 50. FIG. It is sectional drawing which shows typically the structure at the time of being further provided.

Next, a method of reducing external magnetism in the discharge lamp device shown in FIGS. The projection light 60c shown in FIGS. 14 and 15 indicates light extracted from the discharge lamp device when the external magnetism is appropriately reduced, and the projection light 60d is used when the direction of the external magnetism changes. Or the electromagnets 10a to 10h (in the discharge lamp device shown in FIG.
d) shows light extracted from the discharge lamp device when controlled by the current control circuit 40.

First, the luminance sensor 50 detects the luminance of the projection light 60c when the external magnetism is appropriately reduced, and obtains an initial luminance value. And the brightness sensor 50
Sends the initial luminance value to the current control circuit 40. The current control circuit 40 stores the initial luminance value.

Next, the brightness sensor 50 detects the brightness of the projection light 60d when the direction of the external magnetic field changes and the position of the light extracted from the discharge lamp device changes from the projection light 60c to the projection light 60d. , Control brightness value. Then, the luminance sensor 50 outputs the control luminance value to the current control circuit 4.
Send to 0. The current control circuit 40 obtains a difference between the received control luminance value and the stored initial luminance value. If the difference is equal to or more than a predetermined value, the electromagnets 10a to 10h (in the discharge lamp device shown in FIG. The supply of current to the electromagnets 10a to 10d) is turned on / off to change the electromagnet to be operated (in the discharge lamp device shown in FIG.
The direction of the current supplied to the electromagnets 10a to 10d can be reversed by reversing the direction of the current supplied to the electromagnets 10a to 10d). Then, the luminance sensor 50 again detects the luminance of the projection light 60c extracted from the discharge lamp device, obtains a control luminance value, and sends the control luminance value to the current control circuit 40. Then, the current control circuit 40 obtains a difference between the received control luminance value and the initial luminance value, and if the difference is equal to or less than a predetermined value, that is, if the reduction of the external magnetism is appropriately performed, the state is maintained. , The above operation is repeated.

As described above, in the discharge lamp device shown in FIGS. 14 and 15, the current control means 40 selects the electromagnet to be operated or reverses the magnetic direction of the electromagnet based on the detection result of the luminance sensor. Therefore, it is possible to automatically operate the electromagnet located at the optimum location in accordance with the change in the direction of the external magnetism, or to reverse the direction of the magnetism of the electromagnet. Therefore, even if the change in the direction of the external magnetism is unknown, the external magnetism can be reliably reduced.

Further, the magnet 10 in the third embodiment may be moved based on the detection result of the luminance sensor 50. As described in the third embodiment, for example, the magnet 1
Gears are attached to the magnet guide 12 and the magnet guide 12.
1 is provided with a geared motor so that the magnet 10
Can be moved electrically. This geared motor is controlled based on the detection result of the luminance sensor 50.
As a result, the magnet 10 can be moved based on the detection result of the luminance sensor 50.

As described above, if the position of the magnet 10 can be moved based on the detection result of the luminance sensor 50, the magnet is automatically moved to the optimum position even when the direction of the external magnetism changes. Can be moved. Therefore, even if the change in the direction of the external magnetism is unknown, the external magnetism can be reliably reduced.

[0072]

According to the discharge lamp device of the first aspect of the present invention, since the discharge lamp is provided with magnetic reduction means for reducing the magnetism (external magnetism) affecting the discharge in the discharge lamp, the discharge by the external magnetism is provided. Variations in the light emitting point of the lamp can be reduced. As a result, it is possible to provide a system using light from the discharge lamp device according to the present invention with light with less fluctuation and stable irradiation direction.

According to the discharge lamp device of the second aspect of the present invention, since the magnetic shielding material is arranged around the discharge lamp, among the external magnetism, the magnetism generated especially outside the discharge lamp device is reduced. Thus, the influence on the discharge of the discharge lamp can be reduced.

In the discharge lamp device according to claim 3 of the present invention, since the magnetism reducing means is a magnet,
The magnetism generated in the immediate vicinity of the discharge lamp can be reduced as compared with the case where a magnetic shielding material that only blocks external magnetism is used as the magnetism reducing means.

According to the discharge lamp device of the fourth aspect of the present invention, since the magnet is an electromagnet, for example, by changing the current supplied to the electromagnet, the magnetic strength of the electromagnet can be changed. Can be. for that reason,
Even when the intensity of the external magnetism changes, the external magnetism can be reduced.

According to the discharge lamp device of the present invention, since a plurality of electromagnets are provided, for example, the electromagnet to be operated can be selected by controlling the current supplied to each electromagnet. Can be. Therefore, even when the direction of the external magnetism changes, the external magnetism can be reduced by operating the electromagnet of the plurality of electromagnets that corresponds to the direction of the external magnetism.

Further, according to the discharge lamp device of the present invention, since the magnetic strength of the electromagnet can be changed, the magnetic strength of the electromagnet can be appropriately changed according to the strength of the external magnetism. The strength can be adjusted. for that reason,
External magnetism can be reduced more reliably.

Further, according to the discharge lamp device of the present invention, based on the detection result of the luminance sensor,
Since the magnetic strength of the electromagnet is changed, the magnetic strength of the electromagnet can be automatically and optimally adjusted even when the external magnetic strength changes. Therefore, even if the change in the intensity of the external magnetism is unknown, the external magnetism can be reliably reduced.

Further, according to the discharge lamp device of the present invention, the electromagnet to be operated can be selected, so that the electromagnet located at the optimum place is operated according to the direction of the external magnetism. be able to. for that reason,
External magnetism can be reduced more reliably.

According to the ninth aspect of the present invention, since the current control means selects the electromagnet to be operated based on the detection result of the luminance sensor, the direction of the external magnet changes. Even in this case, it is possible to automatically operate the electromagnet located at the optimum location. Therefore, even if the change in the direction of the external magnetism is unknown, the external magnetism can be reliably reduced.

According to the discharge lamp device of the tenth aspect of the present invention, the direction of the magnetism generated by the electromagnet can be reversed. Similar effects can be obtained.

Further, according to the discharge lamp device of the present invention, the current control means reverses the magnetic direction of the electromagnet based on the detection result of the luminance sensor. , The direction of the magnetism of the electromagnet can be automatically reversed. Therefore, even if the change in the direction of the external magnetism is unknown, the external magnetism can be reliably reduced.

According to the discharge lamp device of the twelfth aspect of the present invention, the position of the magnet can be moved by the moving means. The magnet can be moved to a position to reduce external magnetism.

Further, according to the discharge lamp device of the present invention, the position of the magnet can be moved based on the detection result of the luminance sensor, so that when the direction of the external magnetism changes. Even if there is, the magnet can be automatically moved to the optimum position. Therefore, even if the change in the direction of the external magnetism is unknown, the external magnetism can be reliably reduced.

[Brief description of the drawings]

FIG. 1 is a perspective view schematically showing a structure of a discharge lamp device according to Embodiment 1 of the present invention.

FIG. 2 is a front view schematically showing the structure of the discharge lamp device according to Embodiment 1 of the present invention.

FIG. 3 is a perspective view schematically showing a structure of a modified example of the discharge lamp device according to Embodiment 1 of the present invention.

FIG. 4 is a perspective view schematically showing a structure of a discharge lamp device according to Embodiment 2 of the present invention.

FIG. 5 is a front view schematically showing a structure of a discharge lamp device according to Embodiment 2 of the present invention.

FIG. 6 is a perspective view schematically showing a structure of a discharge lamp device according to Embodiment 3 of the present invention.

FIG. 7 is a side view schematically showing a structure of a discharge lamp device according to Embodiment 3 of the present invention.

FIG. 8 is a sectional view schematically showing a structure of a discharge lamp device according to Embodiment 3 of the present invention.

FIG. 9 is a front view schematically showing a structure of a discharge lamp device according to Embodiment 4 of the present invention.

FIG. 10 is a sectional view schematically showing a structure of a discharge lamp device according to Embodiment 5 of the present invention.

FIG. 11 is a sectional view schematically showing a structure of a discharge lamp device according to Embodiment 6 of the present invention.

FIG. 12 is a front view schematically showing a structure of a discharge lamp device according to Embodiment 7 of the present invention.

FIG. 13 is a diagram showing a luminance distribution of the discharge lamp device according to Embodiment 7 of the present invention.

FIG. 14 is a sectional view schematically showing a structure of a discharge lamp device according to Embodiment 7 of the present invention.

FIG. 15 is a sectional view schematically showing a structure of a discharge lamp device according to Embodiment 7 of the present invention.

FIG. 16 is a perspective view schematically showing the structure of a conventional discharge lamp.

[Explanation of symbols]

3 Discharge lamp, 5 outer box, 10, 10a to 10h magnet, 40 current control circuit, 50 brightness sensor, 100
transportation.

Claims (13)

[Claims] 1. A discharge lamp device comprising: a discharge lamp; and a magnetism reducing unit that reduces magnetism affecting a discharge in the discharge lamp. 2. The discharge lamp device according to claim 1, wherein the magnetism reducing means is a magnetic shielding material disposed around the discharge lamp. 3. The discharge lamp device according to claim 1, wherein the magnetism reducing means is a magnet, and the second magnetism generated from the magnet acts in a direction to reduce the magnetism. 4. The discharge lamp device according to claim 3, wherein said magnet is an electromagnet. 5. The electromagnet according to claim 4, wherein a plurality of electromagnets are provided.
The discharge lamp device according to item 1. 6. The apparatus according to claim 4, further comprising a current control unit that controls a current supplied to the electromagnet to change the intensity of the second magnetism of the electromagnet. The discharge lamp device according to item 1. 7. The apparatus according to claim 7, further comprising a luminance sensor for detecting the intensity of the luminance of the light generated from the discharge lamp, wherein the current control means detects the second magnetic field of the electromagnet based on a detection result from the luminance sensor. 7. The discharge lamp device according to claim 6, wherein the intensity is changed. 8. The discharge lamp device according to claim 5, further comprising current control means for selecting the electromagnet to be operated by controlling a current supplied to each of the electromagnets. 9. The apparatus according to claim 1, further comprising a luminance sensor for detecting a luminance intensity of light generated from said discharge lamp, wherein said current control means selects said electromagnet to be operated based on a detection result from said luminance sensor. Item 10. The discharge lamp device according to item 8. 10. The discharge lamp device according to claim 5, further comprising current control means for controlling a current supplied to the electromagnet to reverse the direction of the second magnetism of the electromagnet. 11. A brightness sensor for detecting the intensity of brightness of light generated from the discharge lamp, wherein the current control means detects the second magnetic field of the electromagnet based on a detection result from the brightness sensor. The discharge lamp device according to claim 10, wherein the direction is reversed. 12. The discharge lamp device according to claim 3, further comprising moving means for moving the position of the magnet. 13. The apparatus according to claim 13, further comprising a luminance sensor for detecting a luminance intensity of light generated from the discharge lamp, wherein the moving unit moves the position of the magnet based on a detection result of the luminance sensor. 13. The discharge lamp device according to item 12.