JP2002365723A - Optical axis regulator and optical axis regulation method for discharge lamp - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device and method which are capable of exactly and rapidly regulating the optical axes of a reflector and a discharge lamp. SOLUTION: Respective stages 21 to 25 of a lamp holder 20 are finely adjusted by a motor, etc., in such a manner that the reflected light spots of slits 31 and 32 projected to a screen 40 are made uniform, by which the regulation in X-Y directions is performed and thereafter the regulation on a Z direction is performed at a ratio of the illuminate of the reflected light transmitted through the slits 31 and 32 by an illuminometer 60.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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 for various projector devices.

[0002]

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

A conventional optical axis adjustment for positioning a light emitting point of a discharge lamp at a focal position of a reflector will be described with reference to FIGS. 7 and 8. FIG. FIG. 7 is a diagram for explaining the operation of the conventional optical axis adjusting device, and FIG. 8 is a diagram viewed from the direction A in FIG. Conventionally, the discharge lamp 10
In this state, the discharge lamp 101 is turned on, the reflected light is projected on the screen 103 via the integrator lens 102, and the illuminance on the screen 103 is maximized. The position is adjusted along the X axis (axis orthogonal to the optical axis), the Y axis (axis orthogonal to the optical axis and the X axis), and the Z axis (axis parallel to the optical axis).
Although the screen 103 is actually large, about 1 m ² , it is schematically illustrated in the figure for explanation.
Similarly, light that has passed through the integrator lens 102 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, even when the optical axes of the reflector, the discharge lamp and the integrator lens are shifted, there is a point where the illuminance on the screen is maximized in that state. I can't check if they match. In addition, the integrator lens may be deformed by the heat of the lamp, and even in this case, there is a point on the screen where the illuminance is maximized.

[0006]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, an optical axis adjusting device for a discharge lamp according to the present invention is provided on a rear side of a reflector with a position adjustable along X, Y and Z axes. And a slit plate formed on the front side of the reflector and formed with a plurality of slits for allowing light reflected from a predetermined reflection point of the reflector to pass therethrough, and a screen and / or a slit on which light transmitted through the slit plate is projected. An illuminometer for measuring the illuminance of light transmitted through the plate was arranged.

[0007] Regarding the holder of the reflector, the slit plate, the screen and / or the illuminometer,
It is possible to adopt a configuration in which the rail is slidably engaged with a rail provided along the Z-axis parallel to the light reflected from the reflector.

When the adjustment is performed along the X-axis and the Y-axis, the illuminometer becomes unnecessary, and when the adjustment is performed along the Z-axis, the screen becomes unnecessary. Therefore, it is desirable that the screen and the illuminometer be detachable.

Further, in the method of adjusting the optical axis of a 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 reflection surface of the reflector is passed through a slit plate having a plurality of slits. The reflected light at a plurality of points separated by a predetermined distance from the optical axis is projected onto the screen, and the position of the discharge lamp or the reflector is adjusted in the X-axis and Y-axis directions orthogonal to the optical axis so that the projected spot is uniform. Then, the position of the discharge lamp or the reflector is adjusted in the Z-axis direction parallel to the optical axis by comparing the illuminance of the reflected light transmitted through the slit plate.

Here, it is assumed that a plurality of slits formed in the slit plate are formed on concentric circles inside and outside the optical axis, respectively. The projection spots on each concentric circle are made uniform, and the position adjustment in the Z-axis direction is performed so that the ratio of the total illuminance of the projection spots on the inner concentric circle to the total illuminance of the outer projection spots becomes a predetermined value.

[0011]

Embodiments of the present invention will be described below with reference to the accompanying drawings. Here, FIG. 1 is a front view of the optical axis adjusting device according to the present invention, FIG. 2 is a plan view of the optical axis adjusting device, and FIG. 3 is a diagram showing a slit plate.

In the optical axis adjusting device, a rail R is provided on a base B, and holding members 1 to 6 which can move along the rail and can be fixed at predetermined positions are engaged with the rail R. Although only the holder 2 among the holders 1 to 6 has a different form, they may be all the same or different.

A reflector 10 is fixed to the holder 1. Then, in the fixed state, the optical axis (Z) of the reflected light from the reflector 10 and the rail R become parallel. The front-back direction orthogonal to the optical axis (Z) is defined as an X direction, and the up-down direction orthogonal to the optical axis (Z) is defined as a Y direction.

A lamp holder 20 is fixed to the holder 2 located on the back side of the reflector 10. The lamp holder 20 includes an X-direction moving stage 21, a Z-direction moving stage 22, a Y-direction moving stage 23, a horizontal rotating stage 24, a vertical rotating stage 25, and a chuck 26.
The discharge lamp 7 is held by the chuck 26, and in this state, the discharge lamp 7 faces the inside of the reflector 10 so that the position can be adjusted.

A slit plate 30 is detachably attached to the holder 3 located on the front side of the reflector 10 so that the surface thereof is in the X direction. A plurality of slits (small holes) are formed in the slit plate 30 as shown in FIG. The four inner slits 31 are formed at equal intervals along the inner concentric circle centered on the point where the optical axis passes, and the eight outer slits 32 are formed at equal intervals along the outer concentric circle. The shapes of the slits 31 and 32 are all the same.

A screen 40 is detachably attached to the holder 4 on the downstream side with respect to the optical path of the reflected light from the holder 3, and a condenser lens 50 is attached to and detached from the holder 5 on the downstream side. The illuminometer 60 is attached to the holder 6 on the downstream side so that the vertical position can be adjusted.

The optical axis adjustment performed using the optical axis adjusting device having the above configuration will be described below. In the optical axis adjustment, the adjustment in the XY direction and the adjustment in the Z direction are separately performed. The order may be any order.

The adjustment in the XY directions is performed by using the slit plate 30 and the screen 40 with the condenser lens 50 and the illuminometer 60 removed, as shown in FIG. Since the screen 40 only needs to be larger than the aperture of the reflector 10, the space is considerably smaller than that of the conventional screen, considering that the screen 40 is about ten and several centimeters. If the light emitting point of the discharge lamp 7 does not coincide with the focal point of the reflector 10, the reflected light spot transmitted through the slits 31 and 32 and projected on the screen 40 becomes non-uniform as shown in FIG. I will. Therefore, the stages 21 to 25 of the lamp holder 20 are finely moved by a motor or the like so that the reflected light spots of the slits 31 and 32 projected on the screen 40 are uniform as shown in FIG. .

When the adjustment in the XY directions is completed as described above, the adjustment in the Z direction is performed. The adjustment in the Z direction is performed by removing the screen 40 and using the condenser lens 50 and the illuminometer 60 as shown in FIG.

First, as shown in FIG. 6A, the outer slit 32 is closed by the mask 33, and the illuminance A1 of the reflected light transmitted through the four inner slits 31 is measured by the illuminometer 60. Next, as shown in FIG.
1 is closed by the mask 34, and the illuminance A2 of the reflected light transmitted through the eight outer slits 32 is measured by the illuminometer 60.

When the light emitting point of the discharge lamp 7 coincides with the focal position F of the reflector 10, the reflected light passing through the slit 31 is reflected by the reflector at a distance R1 from the light emitting point, becomes parallel to the optical axis, and passes through the slit 32. The reflected light reflected by the reflector at a distance R2 from the light emitting point is parallel to the optical axis. Therefore, the illuminance A1 of the reflected light passing through the slit 31
And the ratio of the illuminance A2 of the reflected light passing through the slit 32 is R1
And R2 should be inversely proportional to the square of the ratio. Therefore, the slits 31 and 3 are located from the focal point F of the reflector 10 and the optical axis.
2 and the number and area of the slits 31 and 32 are known, the illuminance A1 of the reflected light passing through the slit 31
And the ratio of the reflected light illuminance A2 passing through the slit 32 can be calculated in advance regardless of the light intensity of the discharge lamp 7. Therefore, the adjustment in the Z direction is performed so that the actually measured value becomes the value of A1 / A2 calculated in advance.

The light source device whose optical axis is adjusted by the present invention using the same discharge lamp and the light source device whose optical axis is adjusted by the conventional method using an integrator lens are as follows.
The illuminance of the screen was substantially the same, and it could be confirmed that the screen illuminance was sufficient as an optical axis adjusting device. Further, the variation of the screen illuminance was smaller in the case of the present invention, and a screen with stable quality could be provided.

[0023]

According to the present invention as described above,
When adjusting the optical axis between the reflector and the discharge lamp,
Since there is no need to use an integrator lens array,
Excellent versatility and cost-effective.

Further, in the related art, even when the optical axis of the reflector and the discharge lamp is shifted, there is a portion where the illuminance of the screen is maximized. Therefore, the discharge lamp is fixed to the reflector with the optical axis shifted. There was a risk of doing it,
According to the present invention, it is possible to accurately and easily match the optical axes.

[Brief description of the drawings]

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

FIG. 2 is a plan view of the optical axis adjusting device.

FIG. 3 shows a slit plate.

FIG. 4 is a diagram showing an apparatus configuration when performing adjustment in the XY directions.

FIGS. 5A and 5B are diagrams showing projected images on a screen when there is a shift in the XY directions and when there is no shift.

FIGS. 6A and 6B are diagrams showing an apparatus configuration when adjusting in the Z direction.

FIG. 7 is a diagram illustrating the operation of a conventional optical axis adjusting device.

FIG. 8 is a view seen from a direction A in FIG. 7;

[Explanation of symbols]

1 to 6: holder, 7: discharge lamp, 10: reflector,
Reference numeral 20: lamp holder, 21: X-direction moving stage, 22
... Z-direction moving stage, 23 ... Y-direction moving stage, 2
4: Horizontal rotation stage, 25: Vertical rotation stage, 26: Chuck, 30: Slit plate, 31, 32 ...
Slit, 40 ... Screen, 50 ... Condenser lens, 60
... Illuminometer, B ... Base, R ... Rail.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Shinji Matsubara Inventor 2-1-1 Nakajima, Kokurakita-ku, Kitakyushu-shi, Fukuoka Tochiki Kiki Co., Ltd. (72) Inventor Ayumu Umemoto Nakajima, Kitakyushu-shi, Fukuoka 2-1-1, Totoki Equipment Co., Ltd. (72) Inventor Shintaro Hatate 2-1-1, Nakajima, Kokurakita-ku, Kitakyushu-shi, Fukuoka F-term in Totoki Equipment Co., Ltd. 3K042 AA01 AC06 BB03 BC09 CB01 CB16

Claims (5)

[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 places a discharge lamp on the back side of the reflector in a Z-axis parallel to the reflected light and on the Z-axis. A slit plate in which a lamp holder for adjusting the position along the orthogonal X axis and Y axis is arranged, and a plurality of slits for passing reflected light from a predetermined reflection point of the reflector on the front side of the reflector is formed. An optical axis adjusting device for a discharge lamp, comprising a screen on which light transmitted through a slit plate is projected and / or an illuminometer for measuring illuminance of light transmitted through the slit plate. 2. The optical axis adjusting device for a discharge lamp according to claim 1, wherein Z is parallel to the reflected light from said reflector.
A rail is provided along an axis, and the rail has a holder for the reflector, the slit plate, the screen, and / or
Alternatively, the optical axis adjusting device of the discharge lamp, wherein the illuminometer is slidably engaged. 3. The optical axis adjusting device for a discharge lamp according to claim 2, wherein the screen and the illuminometer are detachable. 4. A lamp is turned on in a state where the position of the discharge lamp can be adjusted relative to the reflector, and a plurality of points on the reflection surface of the reflector that are separated from the optical axis by a predetermined distance through a slit plate having a plurality of slits. The reflected light is projected onto the screen, and the position of the discharge lamp or reflector is adjusted in the X-axis and Y-axis directions perpendicular to the optical axis so that the projected spot becomes uniform. Then, the illuminance of the reflected light transmitted through the slit plate is compared. And adjusting the position of the discharge lamp or the reflector in the Z-axis direction parallel to the optical axis. 5. The method for adjusting the optical axis of a discharge lamp according to claim 4, wherein a plurality of slits are formed on the inner and outer concentric circles centered on the optical axis, respectively. The position adjustment in the axis and Y axis directions is such that the projected spot on each concentric circle is uniform,
The position adjustment in the Z-axis direction is performed so that the ratio of the total illuminance of the projection spots on the inner concentric circle to the total illuminance of the outer projection spots becomes a predetermined value.