JP2003272408A - Optical axis adjustment device and method of discharge lamp - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device and a method capable of adjusting the optical axis of a reflector and a discharge lamp accurately in a short time at a lower cost. <P>SOLUTION: This optical axis adjustment method of the discharge lamp is characterized that the discharge lamp is turned on with its position adjustable relative to the reflector, and justified in the direction of the x-axis and the y-axis orthogonal to the optical axis so that an illuminometer reads the maximum illuminance of light passing through a plurality of slits, and then the z-axis is adjusted so that the discharge lamp is positioned at the center of two illuminance peaks obtained by moving the discharge lamp in the z-axis direction. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical axis adjusting device and an optical axis adjusting method for a discharge lamp such as an ultra-high pressure mercury lamp used in various projector devices that require parallel light.

[0002]

2. Description of the Related Art The structure of a light source device incorporating a discharge lamp is fixed such that the light emitting point of the discharge lamp is located at the focal position of the reflector as disclosed in Japanese Patent Laid-Open No. 2000-260214.

FIGS. 19 and 20 show the conventional optical axis adjustment for positioning the light emitting point P of the discharge lamp at the focal point of the reflector.
It will be described based on. Incidentally, FIG. 19 is a diagram for explaining the operation of the conventional optical axis adjusting device, and FIG. 20 is a diagram viewed from the direction C in FIG. Conventionally, the discharge lamp 101 is held in a state in which the position of the discharge lamp 101 can be adjusted relative to the reflector 100, the discharge lamp 101 is turned on in this state, and the reflected light is passed through the integrator lens 102 to the screen 103.
X axis (axis orthogonal to the optical axis), Y axis (axis orthogonal to the optical axis and X axis), and Z axis (axis parallel to the optical axis) so that the illuminance on the screen 103 is maximized. The position is adjusted along. The screen 103 is actually a large one of about 1 m ² , but is schematically shown in the figure for the sake of explanation. In addition, similarly, the integrator lens 10
The light passing through 2 is normally projected on the screen 103 via an optical system such as a projection lens, but is omitted.

[0004]

In the above-described conventional optical axis adjusting method, the integrator lens 102 must be prepared according to the shape and size of the reflector, which is costly and inferior in versatility.

Further, according to the conventional optical axis adjusting method, 1 m 2
It was necessary to irradiate light on a screen of a certain size, which required a large area.

Even when the optical axes of the reflector, the discharge lamp and the integrator lens are deviated, there is a point where the illuminance on the screen becomes maximum in that state, so that the optical axes of the reflector and the discharge lamp actually coincide with each other. I cannot confirm that

Similarly, the integrator lens may be deformed or deteriorated by the heat of the lamp, and the refractive index of light may change. Even in this case, there is a point where the illuminance on the screen becomes maximum, and therefore there is the same problem as described above.

Further, in the conventional optical axis adjusting device, since the integrator lens is deformed and deteriorated due to heat with time, the optical axes of the reflector and the discharge lamp are also displaced with time. Therefore, the conventional optical axis adjusting device is inconvenient because it requires periodic maintenance and correction.

[0009]

In order to solve the above-mentioned problems, an optical axis adjusting device for a discharge lamp according to the present invention is an optical axis adjusting device for locating a light emitting point of a discharge lamp at a focal position of a reflector. The adjusting device movably arranges a lamp holder for position adjustment along a Z-axis parallel to the reflected light of the discharge lamp, and an X-axis and a Y-axis orthogonal to the Z-axis, and a predetermined reflector is provided on the front side of the reflector. The optical axis of the discharge lamp, which is characterized in that a slit plate having a plurality of slit holes for passing the parallel reflected light from the reflection points of and a illuminance meter for measuring the illuminance of the light passing through the slit holes are arranged. Adjusting device.

The slit plate is characterized in that at least two slit holes are provided in each of the X-axis direction and the Y-axis direction on a circle centered on the optical axis, that is, a total of four slit holes. Since the change in the illuminance of the parallel reflected light from the reflection point of the reflector can be grasped as the information of the position of each axis, the light emitting point position of the lamp can be adjusted to the optical axis position.

The mirror surface shape of the reflector for obtaining parallel light is generally a parabola, and if the formula is expressed as y = P × x2, the slit on the slit plate formed on a circle centered on the optical axis It is characterized in that the distance from the center of the hole is (2 × P) ⁻¹ . If the distance from the center of the slit hole on the slit plate is (2 × P) ⁻¹ , the Z axis can be adjusted.

Further, by providing a shielding means so that the light passing through the slit holes does not enter the light from the other slit holes, the light which may enter obliquely from the other slit holes is shielded. , The illuminance of only the parallel light reflected from the reflector can be measured.

As the shielding means, a plurality of slit plates are arranged. When using at least two slit plates to obtain parallel light, when two slit plates are used,
Oblique light components other than parallel light may also pass through the slit holes. In order to cut this diagonal light component,
Another slit plate is required. Although it is possible to use four or more slit plates, the effect of increasing the number of slit plates cannot be obtained. In order to most effectively cut oblique light components, it is desirable to arrange three slit plates at equal intervals.

In the method of adjusting the optical axis of the discharge lamp according to the present invention, the discharge lamp is lit in a state where the position of the discharge lamp can be adjusted relative to the reflector, and the illuminance of the light passing through the plurality of slit holes is maximized. After the position of the discharge lamp is adjusted in the X-axis and Y-axis directions orthogonal to the optical axis, the discharge lamp is moved in the Z-axis direction to obtain the center of the two illuminance peaks or the minimum of the illuminance between the peaks. It is characterized in that the Z-axis is adjusted so that the discharge lamp is positioned at the position.

The discharge lamp is lit in a state where the position of the discharge lamp can be adjusted relative to the reflector, and the light passing through the plurality of slit holes is measured by an illuminometer so that the discharge lamp is orthogonal to the optical axis so as to maximize the illuminance. After adjusting the X-axis and Y-axis positions, move the discharge lamp in the Z-axis direction and adjust the Z-axis so that the discharge lamp is located at the minimum illuminance position between the two illuminance peaks. The optical axis adjusting method of the discharge lamp is characterized by performing

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the accompanying drawings. 1 is a front view of the optical axis adjusting device according to the present invention, FIG. 2 is a side view of the optical axis adjusting device, and FIG. 3 is a view showing a slit plate S.

In the optical axis adjusting device, holders 1 to 7 are engaged with a base B installed vertically. Base B is installed vertically, but it is installed vertically because it is convenient to fix the discharge lamp and reflector with a fixing adhesive, and it is necessary to be vertical to adjust the optical axis. However, it may be horizontal in some cases. Also a holder
1 to 7 may have the same shape, or may have different shapes. When the discharge lamp A is turned on, the light is reflected by the reflector R. The direction of this reflected light is the Z axis, the direction orthogonal to the Z axis and connecting the base B and the discharge lamp A is the Y axis, and the direction orthogonal to the Z axis and the Y axis is the X axis.

A lamp holder 10 is fixed to the holder 1. This lamp holder 10 is an X-direction moving stage 1
1, Y-direction moving stage 12, Z-direction moving stage 1
3, X-direction rotary stage 14, Y-direction rotary stage 15
And a chuck 16, and the chuck 16 discharges the discharge lamp A.
Is held in the reflector R.

A reflector R is fixed to the holder 2.
It The reflector R is the reflected light of the light emitted from the focus position.
Are designed to be parallel, and the reflection surface is y =
P × x ^TwoIt is a parabola that can be expressed as. Focus position in this case
The distance from the bottom of the reflector to the focal point is (4 ×
P)^-1Becomes

A slit plate S is fixed to the holders 3-5. The number of slit plates used is three, and the distance between each slit plate S and the distance from the reflector R to the slit plate S are arbitrary, but if the distance and the distance are too short, the accuracy of the optical axis adjustment becomes low, If the distance is too long, it becomes difficult to align the Z axis of the reflector R with the three slit plates S. In this embodiment, the distance from the reflector R to the slit plate S is 70 mm, and the distance between the slit plates S is 200 mm. Further, if the diameter of the slit hole 31 provided in the slit plate S is large, the accuracy of the optical axis adjustment is low, and if it is small, the amount of light passing through the slit plate S is small and an error is likely to occur. In this embodiment, the diameter of the slit hole 31 provided in the slit plate S is φ.
It was set to 2 mm.

A lens L is fixed to the holder 6. The distance from the slit plate S to the lens L is arbitrary, and is 70 mm in this embodiment.

An illuminometer M is fixed to the holder 7. The holder 7 is variable about 30 mm in the Z-axis direction, and an illuminance meter M is installed at the condensing point of the light condensed by the lens L. It should be noted that the lens has a desirable form because it can collect light passing through the plurality of slit holes and measure it with one illuminometer. However, by providing a plurality of illuminometers facing the plurality of slit holes, the lens can be It is also possible not to use.

The optical axis adjusting method according to the present invention adjusts the optical axis by measuring the illuminance distribution between the electrodes of the discharge lamp. First, it will be described with reference to the drawings that the illuminance distribution between the electrodes can be measured by using the optical axis adjusting device having the above configuration.

FIG. 4 shows what angle the light reflected by the reflector R has depending on the position of the light emitting point. When the light emitting point 41 is located on the bottom surface side of the focal point position F of the reflector R (a), the reflected light spreads outside the optical axis.
When the light emitting point 41 is at the focal position F of the reflector R (b), the reflected light is parallel to the optical axis. Further light emission point 4
When 1 is located on the opening side of the focal position F of the reflector R (c), the reflected light is condensed inside the optical axis.

FIG. 4 is an explanation of the case of an ideal point light source, but an actual discharge lamp has a pair of electrodes 5 as shown in FIG.
Light is emitted from an arc having a length formed between 1. The distance between the electrodes varies depending on the type of discharge lamp, and the distance between the electrodes is about 1 mm to several mm. FIG. 6 shows what kind of angle the light reflected by the reflector R has in the case of the light source having a length, that is, the arc 61, rather than the ideal point light source. FIG. 6 also shows how the reflected light passes through the two slit plates S having the slit holes 31 at positions parallel to the optical axis.

Both ends of the arc 61 are reflectors R.
In the case (a) on the bottom side of the focal point position F, all the light spreads outside the optical axis, and the light passing through the two slit plates S cannot be obtained. One end of the arc 61 is a reflector R
In the case (b), which is on the bottom side of the focal point position F and the other end is on the opening side of the focal point position F of the reflector R, the light that spreads outside the optical axis and the condensed light are mixed, and some of them are It passes through two slit plates S. When both ends of the arc 61 are both on the opening side of the focal point position F of the reflector R (c), all the light is condensed and the light passing through the two slit plates S cannot be obtained. As described above, by measuring the illuminance of light passing through the two slit plates S while moving the arc 61 from the bottom surface side of the reflector R to the opening side, the illuminance distribution in the length direction of the arc can be seen. It is possible.

When the number of the slit plates S is two, as shown in FIG. 7 (a), the light of the component not parallel to the optical axis is also included in the slit plates S.
May pass through. Therefore, as shown in FIG. 7B, by arranging another slit plate S in the middle of the two slit plates S, it becomes possible to cut the light of the component that is not parallel to the optical axis. The cutting means may be a shield plate arranged in a position parallel to the optical axis.

The slit hole 31 of the slit plate S shown in FIG.
The position of is in the X-axis and Y-axis directions on a circle centered on the optical axis.
There are 4 in total, 2 for each. Circle around the optical axis
Radius is (2 x P)^-1And This is the reflector R
The reflective surface is y = P × x^TwoIn the case of a parabola that can be expressed by
Light emitted perpendicular to the optical axis from the light emitting point 41 existing in F
Is reflected by the reflector and is parallel to the optical axis,
As shown in FIG. 8A, the focus position F is (4 × P)^-1so
Yes, the distance from the optical axis to the reflecting surface is (2 x P) ^-1Tona
It Slit hole 31 has a radius around the optical axis (2 x P)
^-1If it is on the circle of,
The emitted light is reflected at a right angle by the reflector,
It will pass through the hole 31. The slit hole 31 is light
Radius around the axis (2 x P)^-1Deviate from the circle
For example, as shown in FIGS.
The passing light has an angle that is not perpendicular to the optical axis from the light emitting point 41.
The light you have is reflected by the reflector at an angle that is not a right angle.
It is the reflected light. In such a case, correct the illuminance distribution between the electrodes.
It becomes difficult to measure accurately.

Using the optical axis adjusting device as described above,
It was confirmed by actually lighting the discharge lamp that it was possible to measure the illuminance distribution between the electrodes of the discharge lamp. The result will be described with reference to the drawings.

When the AC discharge lamp is turned on by using this optical axis adjusting device, projected images of the electrodes and the arc as shown in FIG. 9 are projected on the slit plate S in the middle. Slit hole 3
Electrodes and arcs appear radial in one direction, the X direction and the Y direction, respectively. FIG. 9A shows an example in which the discharge lamp is displaced from the focus position of the reflector in both the X and Y directions. Further, (b) is an example in which the discharge lamp is displaced from the focal position of the reflector in the Z direction. (C) is a figure when a discharge lamp is located in a focal position of a reflector. First, the X-direction moving stage of the holder 1 adjusts the X-direction so that the illuminance becomes maximum. Similarly, Y of holder 1
The direction moving stage adjusts the illuminance in the Y direction so as to maximize the illuminance. Either the X-direction operation or the Y-direction operation may be performed first, and it is more preferable to repeat the operation. By this operation, the position of the discharge lamp in the X and Y directions with respect to the reflector is determined.

Next, the discharge lamp is moved in the Z direction by the Z-direction moving stage of the holder 1. The result of measuring the illuminance while moving the lamp in the Z direction is shown in FIG.

From this figure, when the discharge lamp was moved in the Z direction, an illuminance distribution having two peaks was obtained. The result will be described. It is generally considered that the state of the arc between the electrodes of the AC discharge lamp is as shown in FIG. From this figure, the arc 61 is thinnest in the vicinity of the electrode 51. This means that the luminous flux is highest near the electrode 51 and the illuminance per unit area, that is, the luminance is also highest. On the other hand, the arc 61 spreads most at the center between the electrodes. This means that the luminous flux is the lowest at the center between the electrodes, and the illuminance per unit area, that is, the luminance is also the lowest. As shown in FIG. 12, the optical axis adjusting device according to the present invention measures the illuminance by passing a small area portion of the arc 61 between the electrodes through a slit. Therefore, when the discharge lamp is moved in the Z direction, When the center of the space reaches the focal point of the reflector (A), the illuminance becomes minimum. On the other hand, when the center between the electrodes deviates from the focal position of the reflector, the illuminance gradually increases, but when the deviation is large (B), the electrodes 51 are reflected in the slit holes and the illuminance decreases.
For this reason, as shown in FIG. 10, it has two peaks and the illuminance is rapidly reduced outside thereof.

In the case of an AC discharge lamp, when moved in the Z direction, the position where the illuminance becomes the minimum and the center position between the peaks coincide. That is, by adjusting the position of the AC discharge lamp in the Z direction to the position where the illuminance becomes the minimum or the position between the peaks, the center between the electrodes can be aligned with the focal position of the reflector.

Next, the case of a DC discharge lamp will be described. The DC discharge lamp was also adjusted in the X and Y directions in the same manner as the AC discharge lamp, and the discharge lamp was moved in the Z direction to measure the illuminance distribution. The result is shown in FIG.

As a result, from the illuminance distribution of the DC discharge lamp, 1
Two large peaks and one small peak are identified.
Also, it can be seen that the center of the peaks is deviated from the minimum position of the illuminance. This will be described with reference to FIG.

In the case of a DC discharge lamp, the size of the paired electrodes is generally different. The small electrode is the cathode 52 and the large electrode is the anode 53. Near the cathode 52,
In the vicinity of the anode 53, since the arc 61 is thinner in the vicinity of the cathode 52, the illuminance has a large peak in the vicinity of the cathode 52, and the illuminance has a smaller peak in the vicinity of the anode 53. Further, the shape of the arc 61 is not symmetrical with respect to the center between the electrodes, and the place where the arc 61 spreads most is shifted to the anode 53 side. Therefore, the minimum illuminance shifts from the center between the electrodes to the anode 53 side. Therefore, even if the position of the DC discharge lamp is adjusted to a position where the illuminance becomes the minimum, the center between the electrodes does not match the focal point of the reflector. By the way, outside the peak, the illuminance is lowered because the electrode is reflected in the slit hole. Therefore,
The center between the peaks should coincide with the center between the electrodes.
In the case of a DC discharge lamp, the center between the electrodes can be adjusted to the focal position of the reflector by adjusting the position in the Z direction to the position between the peaks.

The present optical axis adjusting device can be used not only for adjusting the optical axis of the discharge lamp but also for measuring the illuminance distribution between arcs. The illuminance distribution in the arc length direction (Z direction) is as described above. On the other hand, the same can be applied to the width direction of the arc (X direction and Y direction). The shape of the slit plate S in this case is, as shown in FIG. 15, provided with two slit holes 31 in the X direction or the Y direction on a circle having a radius (2 × P) ⁻¹ centered on the optical axis. . When viewing the illuminance distribution in the X direction, there are two slit holes 31 in the Y direction.
And two slit holes 31 are provided in the X direction when viewing the illuminance distribution in the Y direction. Since the method of viewing the illuminance distribution is the same as the X and Y directions, a method of viewing the illuminance distribution in the X direction will be described here.

As in the case of adjusting the optical axis, the discharge lamp is turned on, the lamp is moved in the Z direction, and the position of the discharge lamp is adjusted to the Z position where the illuminance distribution is desired to be viewed. If the lamp is moved in the X direction as it is, the illuminance distribution in the X direction can be confirmed.

Results of actual measurement using an AC discharge lamp will be described with reference to the drawings. FIG. 16 shows the measured Z position. Z1 is the center between peaks of the illuminance when the lamp is moved in the Z direction. Z3 is the peak position of illuminance. FIG. 17 shows the illuminance distribution in the X direction from Z1 to Z4. At the same time, the peak height, that is, the maximum illuminance and the half width are also shown. As a result, it can be seen that the maximum illuminance increases and the half-value width decreases from the center between the illuminance peaks toward the illuminance peak. Further, during this period, the area of the peak (half-value width × maximum illuminance) is substantially constant. That is, between the peaks of the illuminance, the luminous flux amount is considered to be constant at any Z position of the arc. It is considered that as the arc width becomes smaller, the luminous flux density becomes higher and the brightness also becomes higher. Z4 is a position closer to the electrode tip than the illuminance peak position (Z3). Here, the arc width is smaller than Z3, but the illuminance is also smaller than Z3. From this, it is considered that although the brightness of Z4 is higher than that of Z3, the illuminance measured by this device is lowered because the tip of the electrode is reflected in the slit.

From the above, the illuminance distribution in the X direction and the Y direction can be viewed by using the present optical axis adjusting device. It can be said that the result of FIG. 17 supports the state of the arc between the electrodes described in FIGS.

To see the illuminance distribution in the X and Y directions,
Radius around optical axis (2 x P) as shown in Fig. 15
A slit plate S having two slit holes 31 in the X direction or the Y direction on the ^-1 circle was used. When adjusting the optical axis in the present optical axis adjusting device, the slit plate S of FIG. 15 can be used when adjusting the X direction and the Y direction. However, in order to adjust the X-direction, the Y-direction and the Z-direction using one kind of slit plate, the X-axis is formed on a circle having a radius (2 × P) ⁻¹ centered on the optical axis as shown in FIG. A slit plate S having two slit holes 31 in each of the Y direction and the Y direction is required.

In order to carry out all the adjustments in the X, Y and Z directions using only one type of slit plate, slits are placed at symmetrical positions in the X and Y directions about the optical axis of the slit plate. It is desirable to provide a hole. That is, at least four are required. Considering symmetrical positions in the X and Y directions, there are 8 slit holes, 12 slit holes, 16 slit holes, etc.
However, the more slit holes are provided, the smaller the amount of change in illuminance becomes when performing adjustment in the X and Y directions, and the more difficult it is to make the adjustment.

A lamp whose optical axis is adjusted by the optical axis adjusting device and the optical axis adjusting method of the present invention is compared with a lamp whose optical axis is adjusted by the conventional technique. Therefore, the same lamp is used, and the screen illuminance of the lamp whose optical axis is adjusted by the conventional technique is set to 1
When 00 is set, FIG. 18 shows how the screen illuminance of the lamp whose optical axis is adjusted by the optical axis adjusting device and the optical axis adjusting method is. As a result, the lamp whose optical axis was adjusted by the optical axis adjusting device and the optical axis adjusting method had a screen illuminance equal to or slightly higher than that of the lamp whose optical axis was adjusted by the conventional technique. From this, it was confirmed that it is possible to align the optical axes of the discharge lamp and the reflector by the optical axis adjusting device and the optical axis adjusting method. Further, the variation in screen illuminance was smaller than that of the optical axis adjusting device and the optical axis adjusting method of the present invention, and a stable quality could be provided.

[0044]

As described above, according to the present invention,
When adjusting the optical axis of the reflector and the discharge lamp,
Since it is not necessary to use an integrator lens array,
It is highly versatile and cost effective.

Further, according to the conventional optical axis adjusting method, 1 m ²
Although it is necessary to actually irradiate light on a screen of a size of about a large amount of space, the present invention is very convenient because no screen or large space is required.

Further, in the prior art, even if the optical axes of the reflector and the discharge lamp were deviated, there was a portion where the illuminance of the screen was maximum. Therefore, the discharge lamp was fixed to the reflector with the optical axis deviated. There was a risk that
According to the present invention, the optical axes can be matched accurately and easily.

Similarly, in the prior art, the integrator lens may be deformed or deteriorated by the heat of the lamp and the refractive index of the light may be changed, and there is the same problem as described above. The optical axes of the discharge lamp and the reflector can be aligned with each other.

Further, in the conventional optical axis adjusting device, since the integrator lens is deformed and deteriorated due to heat with time, the optical axes of the reflector and the discharge lamp are also displaced with time, and the device is regularly used. Although maintenance and correction were required, the present invention allows the optical axes of the discharge lamp reflectors to be aligned without the need for such regular maintenance.

[Brief description of drawings]

FIG. 1 is a front view of an optical axis adjusting device according to the present invention.

FIG. 2 is a side view of an optical axis adjusting device according to the present invention.

FIG. 3 is a diagram showing a slit plate.

4 (a), (b) and (c) are schematic diagrams showing what kind of angle the light reflected by the reflector has according to the position of the light emitting point.

FIG. 5 is a diagram showing a distance between electrodes.

6 (a), (b) and (c) are schematic diagrams showing what kind of angle the light reflected by the reflector has in the case of a light source having a length.

7 (a) and 7 (b) are schematic diagrams showing a difference in light passing through a slit when two slit plates are used and when three slit plates are used.

8A, 8B, and 8C are schematic diagrams showing how the reflection angle of the light passing through the slit becomes when the positions of the slit holes are different.

9 (a), (b) and (c) are XY directions and Z.
Diagram showing projected images on the slit plate with and without deviation of the optical axis in the direction

FIG. 10 is a diagram showing changes in illuminance when the AC discharge lamp is moved in the Z direction.

FIG. 11 is a schematic diagram showing a state of an arc between electrodes of an AC discharge lamp.

FIG. 12 is a schematic diagram showing a minute area portion of an arc between electrodes whose illuminance is measured by the optical axis adjusting device.

FIG. 13 is a diagram showing a change in illuminance when a DC discharge lamp is moved in the Z direction.

FIG. 14 is a schematic diagram showing a state of an arc between electrodes of a DC discharge lamp.

FIG. 15 is a diagram showing a slit plate used when measuring the illuminance distribution in the X and Y directions.

FIG. 16 is a schematic diagram showing positions in the Z direction when measuring an illuminance distribution in the X direction.

17 (a), (b), (c), and (d) are X-direction illuminance distributions, maximum illuminances, and half widths when the Z-direction position is Z1, Z2, Z3, and Z4 shown in FIG. Showing

FIG. 18 is a diagram showing a result of comparing screen illuminances of a lamp whose optical axis is adjusted by a conventional technique, and a lamp whose optical axis is adjusted by the present optical axis adjusting device and the optical axis adjusting method.

FIG. 19 is a diagram illustrating the operation of a conventional optical axis adjusting device.

20 is a view seen from the direction C in FIG.

[Explanation of symbols]

1 to 7 ... Holder, 10 ... Lamp holder, 11 ... X direction moving stage, 12 ... Y direction moving stage, 13 ... Z direction moving stage, 14 ... X direction rotating stage, 15 ... Y direction rotating stage, 16 ... Chuck , 31 ... slit holes,
41 ... Light emitting point, 51 ... Electrode, 52 ... Cathode, 53 ... Anode,
61 ... Arc, 91 ... Projection image, A ... Discharge lamp, B ... Base, F ... Focus position, M ... Illuminance meter, R ... Reflector, S
... slit plate

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Ayumu Umemoto             2-1-1 Nakajima, Kokurakita-ku, Kitakyushu City, Fukuoka Prefecture             No. Totoki Equipment Co., Ltd. F-term (reference) 2K103 BA01 BA09 CA24 CA40                 3K013 AA02 BA01 CA12 FA03                 3K042 AA01 AC06 BB03

Claims (7)

[Claims] 1. An optical axis adjusting device for positioning a light emitting point of a discharge lamp at a focal position of a reflector, wherein the optical axis adjusting device is a Z axis parallel to the reflected light of the discharge lamp, an X axis orthogonal to the Z axis, and A slit plate in which a lamp holder for position adjustment along the Y-axis is movably arranged, and a plurality of slit holes for allowing parallel reflected light from a predetermined reflection point of the reflector to pass through is formed on the front surface side of the reflector, An optical axis adjusting device for a discharge lamp, comprising an illuminometer for measuring the illuminance of light passing through this slit hole. 2. The optical axis adjusting device for a discharge lamp according to claim 1, wherein the slit holes formed in the slit plate are at least two in a circle centered on the optical axis in the X-axis direction and the Y-axis direction, respectively. An optical axis adjusting device for a discharge lamp, which is provided with a total of four pieces. 3. The optical axis adjusting device for a discharge lamp according to claim 1, wherein the mirror surface shape of the reflector is y.
= P × x ² , the distance from the center of the slit hole on the slit plate formed on the circle centered on the optical axis is (2 ×
P) ^-1 . An optical axis adjusting device for a discharge lamp. 4. The discharge lamp optical axis adjusting device according to claim 1, wherein a shielding means is provided so that light passing through the slit holes does not enter light from other slit holes. Lamp optical axis adjustment device. 5. The optical axis adjusting device for a discharge lamp according to claim 4, wherein the shielding means is a plurality of slit plates arranged. 6. The discharge lamp is lit in a state in which the position of the discharge lamp can be adjusted relative to the reflector, and the light passing through the plurality of slit holes is measured by an illuminometer so that the illuminance of the discharge lamp is maximized. After adjusting the position in the X-axis and Y-axis directions orthogonal to the direction, the Z-axis is adjusted so that the discharge lamp is positioned at the center between the two illuminance peaks obtained by moving the discharge lamp in the Z-axis direction. A method for adjusting an optical axis of a discharge lamp, comprising: 7. The discharge lamp is lit in a state where the position of the discharge lamp can be adjusted relative to the reflector, and the light passing through the plurality of slit holes is measured by an illuminometer so that the illuminance is maximized. After adjusting the position in the X-axis and Y-axis directions orthogonal to the Z-axis, the Z-axis is positioned so that the discharge lamp is positioned at the minimum position of the illuminance between the two illuminance peaks obtained by moving the discharge lamp in the Z-axis direction. A method for adjusting the optical axis of a discharge lamp, characterized in that