JP5072478B2 - Optical axis automatic adjustment system - Google Patents

Description

  The present invention relates to an optical axis automatic adjustment system, and in particular, when a light beam is present along a preset reference optical path, even if the incident light to the system deviates from the reference optical path, the emitted light enters the reference optical path. The present invention relates to a technique for performing automatic optical axis adjustment so as to maintain a state along the line.

  The light beam is widely used in various industrial fields such as a fine pattern exposure process, a material processing process, and information communication. In an optical system using a light beam, it is important to adjust the optical axis. In particular, in a process of performing precise processing using a laser beam or the like, an accurate optical axis adjustment operation is required. A general optical beam adjusting device for a light beam is configured by a device combining optical elements such as a reflecting mirror and a prism. For example, Patent Documents 1 and 2 below disclose an optical axis adjusting device in which a plurality of reflecting mirrors and prisms are combined.

Even if the optical beam is adjusted so that the light beam passes through a predetermined reference optical path using such an optical axis adjusting device, the light beam may be off the reference optical path due to a physical variation factor of the light source. Not a few. Of course, when such an optical axis shift occurs, the optical axis adjustment may be performed again, but it is not efficient to manually adjust the optical axis every time. Therefore, in Patent Document 3 below, the optical axis is controlled by feedback control so that the incident light beam maintains the state along the reference optical path even when the incident light beam deviates from the preset reference optical path. An automatic adjustment system has been proposed.
JP 2002-229216 A JP 2004-07831 A JP 2005-331541 A

  The conventional general optical axis adjusting device uses a complicated optical system combining a reflecting mirror and a prism, so the structure of the entire device becomes complicated, and the number of reflections inside the device increases. There is a problem in that the light amount of the light beam passing through the apparatus is lost, and the wavefront is deteriorated due to aberrations of the optical system or adhesion of dust. On the other hand, in the system disclosed in Patent Document 3 described above, an optical axis adjustment mechanism using a simpler optical system has been proposed. However, in order to perform feedback control, a part of the light beam is used as a detection beam. A beam splitter to be branched is used, and the light amount loss and the wavefront deterioration in the beam splitter portion are inevitable.

  Therefore, an object of the present invention is to provide an optical axis automatic adjustment system capable of performing automatic optical axis adjustment with a simple structure while minimizing the loss of light amount and the deterioration of the wavefront.

(1) The first aspect of the present invention is that the incident light deviates from the reference optical path when the light beam exists along the reference optical path passing through the predetermined incident point and the exit point in the XYZ three-dimensional coordinate system In addition, in the optical axis automatic adjustment system having the function of performing automatic optical axis adjustment so that the emitted light maintains the state along the reference optical path,
A main body that performs optical axis adjustment, an output unit that emits light from the main body, and a control unit that controls the optical axis adjustment operation by the main body;
The main body is
A first mirror having a reflective surface obtained by rotating a plane parallel to the XY plane by a predetermined angle α (0 ° <α <90 °) about a rotation axis parallel to the Y axis;
A second mirror having a reflecting surface obtained by rotating a plane parallel to the XZ plane by a predetermined angle β (0 ° <β <90 °) about a rotation axis parallel to the X axis;
A support that supports the first mirror and the second mirror at a predetermined position so that incident light is emitted toward the output unit after at least reflecting both of the mirrors in this order;
Position adjusting means for translating the first mirror relative to the support in the X-axis or Z-axis direction, and translating the second mirror in the Y-axis or Z-axis direction;
Angle adjustment with the function of rotating the first mirror about a rotation axis parallel to the Y-axis and the operation of rotating the second mirror about a rotation axis parallel to the X-axis Means,
Have
The output section
A third mirror for reflecting the light beam coming from the main body,
A fourth mirror that reflects and emits the light beam reflected from the third mirror;
Angle detection means for detecting an incident angle of a light beam transmitted through one of the third mirror and the fourth mirror with respect to a predetermined reference plane;
Position detecting means for detecting an incident position on a predetermined reference plane of the light beam transmitted through the other one of the third mirror and the fourth mirror;
Have
The control unit
Storage means for storing the angle and position detected by the angle detection means and the position detection means in a state where the incident light is along the reference optical path;
Control means for controlling the angle adjusting means and the position adjusting means so as to eliminate the deviation when the angle and the position detected by the angle detecting means and the position detecting means deviate from the values stored in the storage means;
Have
The light incident on the output unit reflects only the third mirror and the fourth mirror and exits from the output unit. As the first to fourth mirrors, mirrors having a reflectance of 99.5% or more are used. It is intended to be used.

(2) The second aspect of the present invention is that the incident light deviates from the reference optical path when the light beam exists along the reference optical path passing through the predetermined incident point and the exit point in the XYZ three-dimensional coordinate system In addition, in the optical axis automatic adjustment system having the function of performing automatic optical axis adjustment so that the emitted light maintains the state along the reference optical path,
A main body that performs optical axis adjustment, an output unit that emits light from the main body, and a control unit that controls the optical axis adjustment operation by the main body;
The main body is
A first mirror having a reflective surface obtained by rotating a plane parallel to the XY plane by a predetermined angle α (0 ° <α <90 °) about a rotation axis parallel to the Y axis;
A second mirror having a reflecting surface obtained by rotating a plane parallel to the XZ plane by a predetermined angle β (0 ° <β <90 °) about a rotation axis parallel to the X axis;
A first support that supports the first mirror and the second mirror at a predetermined position so that incident light is emitted toward the output unit after at least reflecting both of the mirrors in this order;
A second support for supporting the first support;
Position adjusting means for translating the first support relative to the second support in the X-axis direction and the Y-axis direction;
Angle adjustment with the function of rotating the first mirror about a rotation axis parallel to the Y-axis and the operation of rotating the second mirror about a rotation axis parallel to the X-axis Means,
Have
The output section
A third mirror for reflecting the light beam coming from the main body,
A fourth mirror that reflects and emits the light beam reflected from the third mirror;
Angle detection means for detecting an incident angle of a light beam transmitted through one of the third mirror and the fourth mirror with respect to a predetermined reference plane;
Position detecting means for detecting an incident position on a predetermined reference plane of the light beam transmitted through the other one of the third mirror and the fourth mirror;
Have
The control unit
Storage means for storing the angle and position detected by the angle detection means and the position detection means in a state where the incident light is along the reference optical path;
Control means for controlling the angle adjusting means and the position adjusting means so as to eliminate the deviation when the angle and the position detected by the angle detecting means and the position detecting means deviate from the values stored in the storage means;
Have
The light incident on the output unit reflects only the third mirror and the fourth mirror and exits from the output unit. As the first to fourth mirrors, mirrors having a reflectance of 99.5% or more are used. It is intended to be used.

(3) A third aspect of the present invention is the optical axis automatic adjustment system according to the first or second aspect described above,
The angle detection means has a condensing lens for condensing parallel rays at a predetermined focal point, and a condensing position on the light receiving surface, the light receiving surface being disposed at a focal distance from the condensing lens. And a light receiving element for detecting.

(4) A fourth aspect of the present invention is the optical axis automatic adjustment system according to the first to third aspects described above,
The position detection means is constituted by a light receiving element that detects the irradiation position of the beam onto a predetermined light receiving surface.

  In the optical axis automatic adjustment system according to the present invention, the two mirrors in the main body are arranged at specific positions, and these mirrors are translated in a specific direction and rotated in a specific direction. Since the angle is adjusted, the optical axis of the light beam can be adjusted with a very simple structure. In addition, it is possible to configure a total of four sets of mirrors, two sets of mirrors in the main unit and two sets of mirrors in the output unit, and the transmitted light from the two sets of mirrors in the output unit is used as a detection beam. Since feedback control can be performed, it is possible to automatically adjust the optical axis with a simple structure while minimizing the loss of light quantity and the deterioration of the wavefront.

  Hereinafter, the present invention will be described based on the illustrated embodiments.

<<< §1. Unique arrangement of two sets of mirrors used in the main body >>>
As shown in FIG. 1, an optical system comprising two sets of mirrors is used in the main body of the optical axis automatic adjustment system according to the present invention. In the present invention, the position and angle of the light beam can be adjusted by arranging the two sets of mirrors at specific positions and moving the mirrors in a specific direction and rotating them in a specific direction. Become important. Therefore, for convenience of explanation, an XYZ three-dimensional coordinate system is defined as shown in the figure, and the specific arrangement and characteristics of the two sets of mirrors are explained on the three-dimensional coordinate system. The two sets of mirrors shown in FIG. 1 and their position angle adjusting means (not shown in FIG. 1) adjust the optical axis of light incident on the XYZ three-dimensional coordinate system and emit it. It can be said that the optical axis adjusting device has

  The most important components of the optical axis adjusting device are the first mirror 10 and the second mirror 20. As shown in the figure, the first mirror 10 and the second mirror 20 are arranged such that their reflection surfaces are at specific positions on the XYZ three-dimensional coordinate system. That is, the reflecting surface M1 of the first mirror 10 is located at a position rotated by a predetermined angle α (0 ° <α <90 °) with respect to the rotation shaft 11 parallel to the Y axis on a surface parallel to the XY plane. The reflecting surface M2 of the second mirror 20 rotates a plane parallel to the XZ plane by a predetermined angle β (0 ° <β <90 °) with respect to a rotating shaft 21 parallel to the X axis. It is arranged to come to the position.

  Here, let us consider a case where the light beam L1 is given as incident light to the optical system including the two mirrors 10 and 20 arranged in this way from a direction parallel to the X axis. In this case, the light beam is reflected by the two mirrors 10 and 20 as shown (the path of this light beam is indicated by a one-dot chain line in the figure). That is, when the light beam L1 is incident on the incident point P1 of the reflecting surface M1 of the first mirror 10, in the illustrated example, a light beam L2 heading substantially upward in the figure is obtained as reflected light. When this light beam L2 is incident on the incident point P2 of the reflecting surface M2 of the second mirror 20, a light beam L3 directed substantially rightward in the figure is obtained as reflected light. Eventually, the light beam L1 given as incident light is reflected twice by this optical system and then emitted as the light beam L3.

  The optical axis adjusting apparatus shown here includes the first mirror 10 and the second mirror 20 described above, a support for supporting these mirrors, and means for adjusting the position and angle with respect to each mirror (both shown in FIG. Is not shown).

  As long as the support member is a component having a function of supporting the two mirrors 10 and 20 at a position that satisfies the above-described specific conditions, the support member may be configured by any structure. For example, the support body may be configured by a frame serving as an apparatus housing, and the first mirror 10 and the second mirror 20 may be attached to the frame. However, it is necessary to attach in such a manner that adjustment by means of adjusting the position and angle is possible.

  The position adjusting means is a component having a function of adjusting the position of the support 10 by moving the mirrors 10 and 20 in a predetermined axial direction. In the present invention, the first mirror 10 needs to be translated in the X-axis direction or the Z-axis direction, and the second mirror 20 needs to be translated in the Y-axis direction or the Z-axis direction. As described above, since various mechanisms for moving the mirror along the predetermined axis are known, such as a mechanism using a guide rail and a slider, a specific description of the moving mechanism is omitted here. To do. As will be described later, the position adjusting means has a function of adjusting the position based on an electrical control signal from the control unit, and is practically configured by an electrically-driven moving mechanism.

  Next, let us consider how the optical axis of the light beam changes when the mirrors 10 and 20 constituting this optical system are translated in a predetermined direction using the position adjusting means.

  FIG. 2 is an XZ sectional view showing an optical axis change caused by translating the reflecting surface M1 (first mirror 10) in the X-axis direction in the optical system shown in FIG. A reflective surface M1 indicated by a solid line in the figure indicates a position before the movement, and a reflective surface M1 ′ indicated by a broken line in the figure indicates a position after the movement. As shown in the figure, before the movement, the light beam L1 is reflected at the incident point P1 on the reflecting surface M1 and emitted as the light beam L2, but when the reflecting surface M1 is translated along the X axis by a displacement amount ΔM1x. Since the incident point with respect to the reflecting surface M1 ′ is at the position P1 ′, the light beam L1 is emitted as the light beam L2 ′. After all, when the reflecting surface M1 is translated in the X-axis direction by the displacement amount ΔM1x, the light beam emitted as reflected light is translated in the X-axis direction by the displacement amount ΔLx. Here, ΔLx = ΔM1x.

  FIG. 3 is an XZ sectional view showing an optical axis change caused by translating the reflecting surface M1 (first mirror 10) in the Z-axis direction in the optical axis adjusting apparatus shown in FIG. Again, the reflecting surface M1 indicated by the solid line in the figure indicates the position before the movement, and the reflecting surface M1 ′ indicated by the broken line in the figure indicates the position after the movement. As shown in the figure, when the reflecting surface M1 is translated by the displacement amount ΔM1z along the Z axis, the incident point with respect to the reflecting surface M1 ′ becomes the position of P1 ′, so that the light beam L1 is emitted as the light beam L2 ′. become. Eventually, when the reflecting surface M1 is translated in the Z-axis direction by the displacement amount ΔM1z, the light beam emitted as reflected light is translated in the X-axis direction by the displacement amount ΔLx. Here, if L1 is parallel to the X axis, ΔLx = ΔM1z / tan α (a predetermined geometric relational expression holds even when L1 is in an arbitrary direction).

  On the other hand, FIG. 4 is a YZ sectional view showing an optical axis change caused by translating the reflecting surface M2 (second mirror 20) in the Z-axis direction in the optical system shown in FIG. A reflective surface M2 indicated by a solid line in the figure indicates a position before the movement, and a reflective surface M2 ′ indicated by a broken line in the figure indicates a position after the movement. As shown in the figure, before the movement, the light beam L2 is reflected at the incident point P2 on the reflecting surface M2 and emitted as the light beam L3. However, when the reflecting surface M2 is translated by the displacement amount ΔM2z along the Z axis, as shown in FIG. Since the incident point with respect to the reflecting surface M2 'is at the position P2', the light beam L2 is emitted as the light beam L3 '. Eventually, when the reflecting surface M2 is translated in the Z-axis direction by the displacement amount ΔM2z, the light beam emitted as reflected light is translated in the Z-axis direction by the displacement amount ΔLz. Here, ΔLz = ΔM2z.

  FIG. 5 is a YZ sectional view showing an optical axis change caused by translating the reflective surface M2 (second mirror 20) in the Y-axis direction in the optical system shown in FIG. Again, the reflecting surface M2 indicated by the solid line in the figure indicates the position before the movement, and the reflecting surface M2 ′ indicated by the broken line in the figure indicates the position after the movement. As shown in the figure, when the reflecting surface M2 is translated along the Y axis by a displacement amount ΔM2y, the incident point with respect to the reflecting surface M2 ′ becomes the position of P2 ′, so that the light beam L2 is emitted as the light beam L3 ′. become. Eventually, when the reflecting surface M2 is translated in the Y-axis direction by the displacement amount ΔM2y, the light beam emitted as reflected light is translated in the Z-axis direction by the displacement amount ΔLz. Here, if L2 is parallel to the Z axis, ΔLz = ΔM2y / tan β (a predetermined geometric relational expression holds even when L2 is in an arbitrary direction).

  As described above, based on the results shown in FIGS. 2 and 3, in order to translate the light beam L2 emitted as the reflected light from the reflecting surface M1 of the first mirror 10 in the X-axis direction, the first mirror 10 is moved. It can be seen that either the parallel movement in the X-axis direction or the parallel movement in the Z-axis direction may be taken. 4 and 5, in order to translate the light beam L3 emitted as the reflected light from the reflecting surface M2 of the second mirror 20 in the Z-axis direction, the second mirror 20 is moved in the Y-axis direction. It can be seen that either one of the methods may be taken, that is, translation in the direction or translation in the Z-axis direction.

  As described above, the position adjusting means translates the first mirror 10 in the X-axis or Z-axis direction with respect to the support and translates the second mirror 20 in the Y-axis or Z-axis direction. It has a function. The former function is for translating the light beam L2 in the X-axis direction, and the latter function is for translating the light beam L3 in the Z-axis direction.

  Eventually, when a light beam L1 parallel to the X-axis is incident as incident light on the optical axis adjusting device having the optical system shown in FIG. 1, the optical path of this light beam is set in two independent axial directions by the position adjusting means. The position of the translation can be adjusted. The operation principle of the optical axis adjusting device shown in FIG. 1 has been described above for the case where the light beam L1 parallel to the X axis is incident. It is not effective only when the beam L1 is incident. That is, even when a light beam slightly inclined with respect to the X-axis is incident, the light beam is reflected by the first mirror 10 and then passes through an optical path that is reflected by the second mirror 20 and emitted. As long as the optical path of this light beam is translated in two independent axial directions, position adjustment can be performed. Therefore, the position adjusting function by the position adjusting means makes it possible to translate the light beam L3 obtained as the light emitted from the optical axis adjusting device to an arbitrary position. Further, due to the reversibility of the optical path, when incident light having a direction opposite to that of the light beam L3 is given, emitted light having a direction opposite to that of the light beam L1 can be obtained, and the optical axis can be adjusted similarly.

<< Example of fixing §2.2 pairs of mirrors to the same support >>>>
As already described in §1, the position adjusting means has a function of translating the first mirror 10 in the X-axis or Z-axis direction, and the second mirror 20 in the Y-axis or Z-axis direction. What is necessary is just to have the function to translate. Therefore, for example, a rail for sliding the first mirror 10 along the X axis or a rail for sliding along the Z axis is disposed on the support, and the first mirror 10 is slidably mounted on the support. Similarly, a rail for sliding the second mirror 20 along the Y-axis or a rail for sliding along the Z-axis is arranged on the support, and the second mirror 20 is slidable. If it mounts on a support body, a position adjustment means can be comprised using these rails.

  As described above, in carrying out the present invention, it is of course possible to provide a mechanism for individually and independently translating the first mirror 10 and the second mirror 20 in a predetermined direction. An embodiment in which the mirror 10 and the second mirror 20 are fixed to the same support will be described. In the embodiment described here, the first mirror 10 and the second mirror 20 are fixed to the first support while maintaining the positional relationship as shown in FIG. And the 2nd support body which supports this 1st support body so that it can move freely is prepared, and the 1st support body with respect to the 2nd support body by the position adjusting means It is possible to translate in the Y-axis direction.

  For example, consider another coordinate system xyz that completely overlaps the coordinate system XYZ shown in FIG. 1, and define the coordinate system XYZ as a stationary coordinate system and the coordinate system xyz as a moving coordinate system. FIG. 1 shows a state where the origins O of both coordinate systems are completely overlapped, but the moving coordinate system xyz can be translated in the X-axis direction and the Y-axis direction with respect to the stationary coordinate system XYZ. It is assumed that it is a movable coordinate system. Here, the first support is constituted by a physical frame along each coordinate axis xyz of the movable coordinate system xyz, and the second support is formed by a physical frame along each coordinate axis XYZ of the stationary coordinate system XYZ. Let's assume that it is configured. As will be described later, the second support is a component that functions as a housing of the main body of the optical axis automatic adjustment system according to the present invention.

  Now, the first mirror 10 and the second mirror 20 are fixed to the first support (movable coordinate axis xyz), and the first support (movable coordinate axis xyz) is fixed to the second support (stationary coordinate axis XYZ). On the other hand, a position adjusting means that can be translated in the X axis direction and the Y axis direction is provided. With such a configuration, although the positional relationship between the first mirror 10 and the second mirror 20 is always constant, the position with respect to the stationary coordinate system XYZ changes.

  For example, if the first support body (coordinate axis xyz) is translated by ΔX in the X-axis direction by the position adjusting means, the first mirror 10 and the second mirror 20 are both on the stationary coordinate system XYZ. It is displaced by ΔX in the X axis direction. Here, when attention is paid to the displacement of the first mirror 10, as shown in FIG. 2, this displacement functions to displace the light beam L2 by ΔLx in the X-axis direction. However, paying attention to the displacement of the second mirror 20, as is apparent from the perspective view of FIG. 1, even if the second mirror 20 is displaced in the X-axis direction, it contributes to the displacement of the light beam L3. do not do. Eventually, the position adjustment operation of translating the first support relative to the second support in the X-axis direction is an independent adjustment operation for displacing the light beam L2 in the X-axis direction as shown in FIG. It turns out that.

  On the other hand, if the first support (coordinate axis xyz) is translated by ΔY in the Y-axis direction by the position adjusting means, both the first mirror 10 and the second mirror 20 are on the stationary coordinate system XYZ. It is displaced by ΔY in the Y-axis direction. Here, focusing on the displacement of the second mirror 20, as shown in FIG. 5, this displacement functions to displace the light beam L3 by ΔLz in the Z-axis direction. However, paying attention to the displacement of the first mirror 20, as is apparent from the perspective view of FIG. 1, even if the first mirror 10 is displaced in the Y-axis direction, it contributes to the displacement of the light beam L2. do not do. After all, the position adjustment operation of translating the first support relative to the second support in the Y-axis direction is an independent adjustment operation for displacing the light beam L3 in the Z-axis direction as shown in FIG. It turns out that.

  The feature of the embodiment described in this §2 is that it is not necessary to perform independent and independent position adjustment operations (translation operations) on the first mirror 10 and the second mirror 20, and the drive system is simplified. Is that you can. That is, the first mirror 10 and the second mirror 20 are mounted on the same support body as the first support body, and the first support body with respect to the second support body by the position adjusting means. When they are translated, they are displaced by the same amount of displacement in the same direction. Nevertheless, when the translation in the X-axis direction is performed, only the displacement in the X-axis direction of the light beam L2, which is the reflected light of the first mirror 10, occurs, and the translation in the Y-axis direction is performed. As a result, only the displacement of the light beam L3, which is the reflected light of the second mirror 20, in the Z-axis direction occurs, and position control in the two directions of the final emitted light from this optical axis adjusting device is independent. Can be done.

<<< §3. Angle adjustment function >>>
In §1 and §2, when an optical system comprising two sets of mirrors satisfying the specific arrangement conditions as shown in FIG. 1 is prepared and each mirror is moved in a specific direction, a light beam obtained as emitted light It was shown that a position adjustment function for translating the two in two directions can be realized. Thus, if the position adjustment in two directions of the emitted light can be performed independently, the light beam can be translated to an arbitrary position.

  In this specification, the adjustment of the optical axis that translates the light beam in this way is called “position adjustment”. On the other hand, the adjustment of the optical axis that changes the direction of the light beam is referred to as “angle adjustment”. That is, the adjustment that maintains the parallel relationship between the light beam before adjustment and the light beam after adjustment is “position adjustment”, whereas the light beam before adjustment and the light beam after adjustment are parallel. Adjustments that do not maintain this relationship are called “angle adjustments”.

  If the optical axis adjustment that combines the adjustment of the position of the light beam obtained as the emitted light (adjustment by parallel movement) and the adjustment of the angle (adjustment to change the direction) can be performed, all adjustments required in practice can be handled. It becomes possible to do. In §3, a mechanism of “angle adjustment” for the optical system shown in FIG. 1 will be described.

  FIG. 6 shows an axis (incident in the figure) passing through the reflecting surface M1 (first mirror 10) through a predetermined point P1 (in the figure, the incident point of the light beam L1) and parallel to the Y axis in the optical system shown in FIG. FIG. 10 is an XZ sectional view showing an optical axis change caused by tilting in a direction of rotation about an axis perpendicular to the paper surface set at the point P1. A reflective surface M1 indicated by a solid line in the figure indicates a position before the inclination, and a reflective surface M1 ′ indicated by a broken line in the figure indicates a position after the inclination. As shown in the figure, before tilting, the light beam L1 is reflected at the incident point P1 on the reflecting surface M1 and is emitted as the light beam L2, but when the reflecting surface M1 is rotated as indicated by the broken line, the incident angle is changed. Therefore, the light beam L1 is emitted as the light beam L2 '. Eventually, when the reflecting surface M1 is rotated by an angle δ as shown in the figure, the direction of the light beam emitted as reflected light changes by an angle 2δ.

  FIG. 6 shows an example in which the incident point P1 of the light beam L1 coincides with the point P1 on the rotation axis of the reflecting surface M1, but the incident point of the light beam L1 is on the reflecting surface M1. Even if the reflecting surface M1 is rotated with an arbitrary axis parallel to the Y axis as a rotation axis, the emission direction of the light beam L2 changes with respect to the degree of freedom parallel to the XZ plane. There is no. Therefore, in practice, an angle adjustment mechanism that rotates the reflecting surface M1 about an arbitrary axis parallel to the Y axis as a rotation axis may be prepared.

  FIG. 7 shows an axis parallel to the X axis (in the drawing, incident on the reflecting surface M2 (second mirror 20) through a predetermined point P2 (incident point of the light beam L2 in the figure) in the optical system shown in FIG. It is a YZ cross-sectional view showing an optical axis change caused by tilting in a direction of rotation about an axis perpendicular to the paper surface set at the point P2. A reflective surface M2 indicated by a solid line in the figure indicates a position before the inclination, and a reflective surface M2 ′ indicated by a broken line in the figure indicates a position after the inclination. As shown in the figure, before tilting, the light beam L2 is reflected at the incident point P2 on the reflecting surface M2 and emitted as the light beam L3. However, when the reflecting surface M2 is tilted as indicated by a broken line, the incident angle changes. Therefore, the light beam L2 is emitted as the light beam L3 ′. Eventually, when the reflecting surface M2 is rotated by an angle δ as shown in the figure, the direction of the light beam emitted as the reflected light changes by the angle 2δ.

  FIG. 7 shows an example in which the incident point P2 of the light beam L2 coincides with the point P2 on the rotation axis of the reflecting surface M2, but the incident point of the light beam L2 is on the reflecting surface M2. Even if the reflecting surface M2 is rotated with an arbitrary axis parallel to the X axis as the rotation axis, the emission direction of the light beam L3 changes with respect to the degree of freedom parallel to the YZ plane. There is no. Therefore, in practice, an angle adjusting mechanism that rotates the reflecting surface M2 about an arbitrary axis parallel to the X axis as a rotation axis may be prepared.

  As described above, the angle adjustment of the light beam can be performed by rotating the first mirror 10 about an arbitrary rotation axis parallel to the Y axis, and the second mirror 20 can be adjusted to the X axis. It can also be performed by an operation of rotating about any parallel rotation axis. In addition, the direction adjustment direction of the light beam that is changed by performing the above-described rotation operation on the first mirror 10 (the adjustment direction that changes the direction of the light beam along a plane parallel to the XZ plane as shown in FIG. 6). ) And the direction adjustment direction of the light beam that is changed by performing the above rotation operation on the second mirror 20 (as shown in FIG. 7, adjustment to change the direction of the light beam along a plane parallel to the YZ plane). Therefore, the angle of the light beam can be adjusted with two independent degrees of freedom by rotating the first mirror 10 and rotating the second mirror 20. By combining the angle adjustment with these two degrees of freedom, it becomes possible to adjust the direction of the light beam in any direction in the three-dimensional space.

  Further, the important point here is that even if the first mirror 10 is rotated by a predetermined amount about the rotation axis parallel to the Y axis, the inherent condition of the first mirror 10 shown in FIG. The condition of having a reflecting surface M1 that is a plane parallel to the Y axis rotated by a predetermined angle α (0 ° <α <90 °) with respect to the rotation axis parallel to the Y axis is maintained, and the second mirror 20 is moved along the X axis. 1 is rotated by a predetermined amount about the rotation axis parallel to the second mirror 20 shown in FIG. 1, that is, “a plane parallel to the XZ plane is set to a predetermined angle β with respect to the rotation axis parallel to the X axis. The condition “having the reflecting surface M2 rotated by 0 ° <β <90 °” is maintained. For this reason, the position adjustment function (position adjustment function described in §1, §2) that translates the optical path of the incident light beam in two independent axial directions causes the first mirror 10 and the second mirror 20 to move. Even if it is rotated under the above conditions, it functions without any problem.

  Since various mechanisms for inclining the reflecting surface of the mirror with a predetermined axis as a rotation axis are known, a description of a specific inclination mechanism of the angle adjusting means is omitted here. As will be described later, the angle adjusting means has a function of adjusting the angle based on an electrical control signal from the control unit, and is practically configured by an electrically driven tilt mechanism.

<<< §4. Overall configuration of optical axis automatic adjustment system >>>
Here, an embodiment of an automatic optical axis adjustment system using the optical axis adjustment device shown in FIG. 1 will be described with reference to the block diagram of FIG. This optical axis automatic adjustment system is also used in the case where a light beam is present along a reference optical path passing through a predetermined incident point Pi and exit point Po in an XYZ three-dimensional coordinate system, and the incident light is off the reference optical path. , And has a function of performing automatic optical axis adjustment so that the emitted light maintains a state along the reference optical path.

  For example, in the example shown in FIG. 8, the light beam L1 passing through the incident point Pi is given as the incident light to the optical axis automatic adjustment system, and is emitted as the light beam L5 passing through the emission point Po. Here, as long as the light beam L1 is stable incident light, a certain reference optical path (optical paths of the light beams L1 to L5 indicated by a one-dot chain line in the figure) passing through the incident point Pi and the emission point Po is ensured. become. However, when the light beam L1 is generated using a laser light source or the like, the light beam L1 as the incident light deviates from the reference optical path due to instability or aging at the start of the laser light source, and the incident light shown in FIG. A situation may occur in which the point Pi is not passed. In the optical axis automatic adjustment system shown here, even when the light beam L1 as the incident light deviates from the reference optical path, the light beam L5 as the emitted light remains unchanged along the reference optical path. Automatic optical axis adjustment can be performed.

  As shown in the figure, the basic components of the optical axis automatic adjustment system include a main body 100 that performs optical axis adjustment, an output unit 200 that emits light from the main body 100, and an optical axis adjustment operation performed by the main body 100. It is the control part 300 which controls.

  In the case of the embodiment shown here, the main body 100 has a mechanism for adjusting the position by translating the light beam by the method described in §2, and the light beam by rotating each mirror by the method described in §3. And a mechanism for adjusting the direction (angle) of the. Hereinafter, the configuration will be described in more detail.

  As shown in FIG. 8, the main body 100 is provided with a first support 110, and the first mirror 10 and the second mirror 20 are shown in FIG. 1 on the first support 110. It is attached so as to maintain the mutual positional relationship. That is, the reflecting surface M1 of the first mirror 10 is a surface obtained by rotating a surface parallel to the XY plane by a predetermined angle α (0 ° <α <90 °) about a rotation axis parallel to the Y axis. The reflecting surface M2 of the second mirror 20 is a surface obtained by rotating a surface parallel to the XZ plane by a predetermined angle β (0 ° <β <90 °) with respect to a rotation axis parallel to the X axis. In this example, the first support 110 is a box-shaped structure, and the first mirror 10 and the second mirror 20 are accommodated therein. In short, the first support 110 emits the first mirror 10 and the second mirror 20 toward the output unit 200 after the incident light L1 reflects at least both the mirrors in this order. , Has a function of supporting at a predetermined position.

  Angle adjusting means 120 is provided in the first support 110. The angle adjusting means 120 is a component that adjusts the angle (direction) of the light beam by rotating the first mirror 10 and the second mirror 20. Specifically, an operation of rotating the first mirror 10 about a rotation axis parallel to the Y axis is performed as in the example shown in FIG. By this rotation operation, the direction of the projection image onto the plane parallel to the XZ plane of the light beam L2 is adjusted. The second mirror 20 is operated to rotate about a rotation axis parallel to the X axis, as in the example shown in FIG. By this rotation operation, the direction of the projected image on the plane parallel to the YZ plane of the light beam L2 is adjusted.

  The position adjusting unit 130 is a driving unit provided between the first support 110 and the second support 140. In this example, the second support 140 is composed of a structure serving as a pedestal, and functions to support the entire first support 110. The position adjusting means 130 has a function of translating the first support 110 with respect to the second support 140 in the X-axis direction and the Y-axis direction. This position adjusting means 130 can be constituted by, for example, an XY stage that can be driven by a stepping motor.

  Such position adjusting means 130 includes a mechanism for adjusting the position by translating the light beam by the method described in §2, and supports the first mirror 10 and the second mirror 20. The first support 110 is moved in parallel with the second support 140 in the X-axis direction and the Y-axis direction. You may use what was provided with the mechanism in which a beam is translated and adjusts a position. In that case, the first mirror 10 and the second mirror 20 are supported by some support, and the position adjusting means translates the first mirror 10 in the X-axis or Z-axis direction relative to the support. In addition, the second mirror 20 only needs to have a function of translating the second mirror 20 in the Y-axis or Z-axis direction.

  On the other hand, the output unit 200 includes a third mirror 30 that reflects the light beam L3 (that is, reflected light from the second mirror 20) coming from the main body unit 100, and a light beam L4 reflected by the third mirror 30. The fourth mirror 40 that reflects the light and emits it to the outside, the angle detection means 210 that detects the angle (direction) of the light beam L30 that has passed through the reflection surface M3 of the third mirror 30, and the fourth mirror 40 Position detecting means 220 for detecting the position of the light beam L40 transmitted through the reflecting surface M4. The third mirror 30 and the fourth mirror 40 do not need to have a position and angle adjustment function, and may be simple fixed mirrors. In this embodiment, each of these mirrors has a reflecting surface rotated about a rotation axis parallel to the X axis on a plane parallel to the XY plane.

  The angle detection unit 210 has a function of detecting an incident angle (an angle relating to two degrees of freedom) of the light beam L30 transmitted through the reflection surface M3 of the third mirror 30 with respect to a predetermined reference surface as an electrical signal. For example, when a plane parallel to the XZ plane is set as the predetermined reference plane, an angle indicating the direction on the plane parallel to the XY plane and an angle indicating the direction on the plane parallel to the YZ plane are detected. Can do. A specific measurement system for realizing the angle detection unit 210 will be described later.

  On the other hand, the position detecting means 220 is a component that detects the incident position of the light beam L40 that has passed through the reflecting surface M4 of the fourth mirror 40 onto the predetermined reference plane, and the position of the light beam L4 that is shifted from the reference optical path. That is, it is a component for detecting the amount of translation. For example, if a plane parallel to the XY plane is a predetermined reference plane, the X coordinate value and the Y coordinate value of the actual position of the light beam L40 on the predetermined reference plane are acquired as position detection values. If you can. A specific measurement system for realizing the position detection unit 220 will be described later.

  The output unit 200 is a stationary component similar to the second support 140, and the housing of the output unit 200 is practically fixed to the second support 140. Good. As described above, if the XYZ coordinate system is a stationary coordinate system, the output unit 200 and the second support 140 are components fixed on the XYZ coordinate system. On the other hand, the first support 110 is a component that moves in the X-axis direction and the Y-axis direction on the XYZ coordinate system by the adjustment operation of the position adjusting means 130. The xyz coordinate system defined above is a moving coordinate system.

  The light beam L1 of the incident light passing through the incident point Pi is reflected at the incident point P1 on the reflecting surface M1 of the first mirror 10 to become the light beam L2, and further incident on the reflecting surface M2 of the second mirror 20. The light beam L3 is reflected at the point P2. The light beam L3 is reflected by the reflecting surface M3 of the third mirror 30 to become a light beam L4, and this light beam L4 is reflected by the reflecting surface M4 of the fourth mirror 40 to become the light beam L5. It is injected from the outside.

  However, since it is practically difficult to form an ideal reflecting surface with a reflectance of 100%, the reflectance at each of the reflecting surfaces M1, M2, M3, and M4 is actually 100%. Don't be. In the case of a general mirror, only a reflectance of about 99.5% can be obtained, and 0.5% is transmitted through the reflecting surface as transmitted light, resulting in a loss of light amount. As described above, the present invention adopts a configuration in which angle detection and position detection are performed by effectively using inevitable transmitted light in practice. That is, no transmitted light transmitted through the reflective surface M1 of the first mirror 10 or the reflective surface M2 of the second mirror 20 is used, but the transmitted light L30 transmitted through the reflective surface M3 of the third mirror 30 is The transmitted light L40 that has been used for angle detection by the angle detection means 210 and has passed through the reflection surface M4 of the fourth mirror 40 is used for position detection by the position detection means 220. Both the transmitted light L30 and L40 are useless leaking light that originally causes a loss of light quantity, but are practically inevitable leaking light. In the present invention, inevitable leakage light is effectively used for angle detection and position detection as described above, and thus it is possible to suppress the loss of light amount as much as possible.

  On the other hand, as shown in the figure, the control unit 300 includes a position control unit 310, a position storage unit 320, an angle control unit 330, and an angle storage unit 340. In practice, the control unit 300 is a processor or computer having an arithmetic processing function. Composed. The position storage means 320 and the angle storage means 340 store the positions and angles detected by the position detection means 220 and the angle detection means 210 in a state where the light beam L1 given as incident light is given along the reference optical path. It has the function to do. When the light beam L1 is given along the reference optical path, the light beam L5 is also emitted along the reference optical path. Therefore, the operator gives a storage instruction to the control unit 300 at that time. As a result, the current position and angle (orientation) of the light beam L5 are detected by the position detection unit 220 and the angle detection unit 210, and stored as reference values in the position storage unit 320 and the angle storage unit 340. Become.

  Thus, after the position and angle reference values are stored in the position storage means 320 and the angle storage means 340, automatic control by the position control means 310 and the angle control means 330 is performed. That is, the position control unit 310 has a function of controlling the position adjustment unit 130 so as to eliminate the shift when the position detected by the position detection unit 220 is shifted from the value stored in the position storage unit 320. . When receiving such a control input, the position adjusting unit 130 performs an operation of translating the first support 110 in the X-axis direction or the Y-axis direction as described above. On the other hand, the angle control unit 330 has a function of controlling the angle adjustment unit 120 so as to eliminate the deviation when the angle detected by the angle detection unit 210 deviates from the value stored in the angle storage unit 340. . When receiving such a control input, the angle adjusting unit 120 performs an operation of rotating the first mirror 10 and the second mirror 20 in a predetermined direction as described above.

  By such feedback control, even when the light beam L1 given as incident light deviates from the reference optical path, the optical axis adjustment relating to the position and angle of the light beam is automatically performed in the main body 100, The light beam L5 as the emitted light is along the reference optical path as in the previous state.

  Finally, specific configuration examples of the angle detection unit 210 and the position detection unit 220 will be described with reference to FIGS. 9 and 10. First, a specific measurement system of the angle detection unit 210 and the principle of angle detection will be described with reference to FIG. This angle detection means 210 is comprised by the condensing lens 211 and the light receiving element 212 as shown in the figure. The condensing lens 211 is a convex lens that condenses parallel light rays at a predetermined focal point, and the light receiving element 212 is a light receiving surface (condensing lens) disposed at a position away from the condensing lens 211 by the focal length. And the function of detecting the condensing position on the light receiving surface. That is, in this example, the light receiving element 212 has a light receiving surface parallel to the XZ plane, and a point Q31 on the light receiving surface is the focal position of the condenser lens 211. The incident angle of the light beam incident on the light receiving surface (incident angle when the condensing lens 211 is not provided) can be detected as two independent numerical values.

  For example, consider a case where a light beam L31 (corresponding to the transmitted light L30 shown in FIG. 8) as indicated by a solid line is given as incident light. The light beam L30 passes through the condenser lens 211 and is applied to the incident point Q31 on the light receiving element 212. If the light receiving element 212 has a function of outputting the incident point position on the light receiving surface (for example, a plane parallel to the XZ plane) as an electrical signal indicating the XZ coordinate value, the XZ coordinate value of the incident point Q31 shown in the figure. Is output as the detected angle value.

  Here, let us consider a case where a light beam L32 (indicated by a one-dot chain line in the drawing) is given instead of the light beam L31. In this case, since the light beam L31 and the light beam L32 are parallel, the light beam L32 is condensed at the focal point Q31 in the same manner as the light beam L31 is condensed at the focal point Q31. Therefore, the output of the light receiving element 212 is the XZ coordinate value of the focal point Q31 regardless of whether the light beam L31 is given or the light beam L32 is given.

  However, suppose that the angle (direction) of the light beam L31 is shifted and tilted like a light beam L33 as indicated by a broken line. Then, the incident point on the light receiving element 212 is shifted from the point Q31 to the point Q33. This is because the light beam L31 indicated by the solid line and the light beam L33 indicated by the broken line are not parallel, so that the condensing point by the condensing lens 211 is shifted. Thus, when the light beam L33 is given, the output of the light receiving element 212 is the XZ coordinate value of the condensing point Q33, and the coordinate value is the incident angle (condensing lens 211) of the light beam L33 with respect to the light receiving surface. (Incident angle when there is no) is a value indicating two degrees of freedom.

  As described above, the XZ coordinate value output from the light receiving element 212 indicates only a factor related to the angle of incident light, and does not include a factor related to the position (translation). In other words, even if there are a plurality of light beams incident on the condensing lens 211, they are condensed at the same point on the light receiving surface of the light receiving element 212 as long as they are parallel to each other. Therefore, even if a position change occurs in the light beam L30 in FIG. 8 (that is, even if the light beam L3 is shifted to a position translated from the reference optical path), the change in the position will be described later. Thus, it is detected only by the position detection means 220 and is not detected by the light receiving element 212 constituting the angle detection means 210. In addition, the angle detection result is a factor having two degrees of freedom, that is, the X coordinate value and the Z coordinate value, and the X coordinate value indicates the direction of the projection image of the light beam toward the light receiving surface onto the XY plane. Thus, the Z coordinate value indicates the direction of the projected image of the light beam directed to the light receiving surface onto the YZ plane.

  Therefore, the angle control unit 330 refers to the coordinate value stored in the angle storage unit 340 and, for example, if there is a shift in the X coordinate value on the light receiving surface of the light receiving element 212, the first control unit 330 When a rotation operation is performed on the mirror 10 in a direction to eliminate the shift, and a shift occurs with respect to the Z coordinate value on the light receiving surface of the light receiving element 212, the shift is corrected with respect to the second mirror 20. What is necessary is just to perform rotation operation in the direction canceled.

  Next, a specific measurement system of the position detection unit 220 and the principle of position detection will be described with reference to FIG. As shown in the figure, the position detection unit 220 includes a light receiving element 221 that detects a beam irradiation position on a predetermined light receiving surface. Here, it is assumed that the light receiving surface of the light receiving element 221 is a plane parallel to the XY plane, and has a function of outputting an incident point position on the light receiving surface as an electric signal indicating an XY coordinate value.

  Consider a state where a light beam L41 (corresponding to the transmitted light L40 shown in FIG. 8) as shown by a solid line in FIG. As shown in the figure, the light beam L41 is applied to the incident point Q41 on the light receiving element 221, and the XY coordinate value of the illustrated incident point Q41 is output as a position detection value.

  Here, let us consider a case where a light beam L42 (indicated by a one-dot chain line in the figure) obtained by translating the light beam L41 slightly to the right is given instead of the light beam L41. In this case, the light beam L42 is irradiated to the incident point Q42 on the light receiving element 221 as illustrated, and the XY coordinate value of the illustrated incident point Q42 is output as a position detection value. Thus, the XY coordinate value output from the light receiving element 221 is a value indicating the positional deviation of the transmitted light L40 shown in FIG. 8 (the amount of parallel movement of the light beam L4 with respect to the reference optical path) in two degrees of freedom. That is, the deviation of the X coordinate value is a value indicating the amount of parallel movement in the X axis direction, and the deviation of the Y coordinate value is a value indicating the amount of translation in the Y axis direction.

  Accordingly, when the position control unit 310 refers to the coordinate values stored in the position storage unit 320 and can confirm that there is a deviation with respect to the X coordinate value, the position control unit 310 moves the first support 110. It is only necessary to eliminate the deviation by translating in the X-axis direction (the principle of FIG. 2), so that the light beam L2 reflected by the first mirror 10 translates in the X-axis direction. In addition, as a result of referring to the coordinate values stored in the position storage unit 320, when it is confirmed that a deviation with respect to the Y coordinate value has occurred, the first support 110 is translated in the Y-axis direction. (Principle of FIG. 5), thereby, the light beam L3 reflected by the second mirror 20 is translated in the Z-axis direction, and as a result, the light beam L4 reflected by the third mirror 30 becomes Y What is necessary is just to eliminate a shift | offset | difference so that it may translate in an axial direction.

  Of course, in the case of adopting a mechanism for adjusting the position by translating the light beam by the method described in §1, if there is a shift in the X coordinate value, the first mirror 10 is moved in the X axis direction. To eliminate the deviation (the principle of FIG. 2), or to move the first mirror 10 in the Z-axis direction to eliminate the deviation (the principle of FIG. 3). If a deviation occurs, the second mirror 20 is translated in the Z-axis direction to eliminate the deviation (the principle of FIG. 4), or the second mirror 20 is translated in the Y-axis direction. Thus, the deviation may be eliminated (the principle of FIG. 5).

  Now, let us consider a case where a light beam L43 (indicated by a broken line in the drawing) is given in FIG. 10 instead of the light beam L41. In this case, the light beam L43 is irradiated to the incident point Q43 on the light receiving element 221 as illustrated, and the XY coordinate value of the illustrated incident point Q43 is output as a position detection value (originally, This is the value that should be the detected angle value).

  As described above, the detection result of the light receiving element 212 illustrated in FIG. 9 includes only the change in angle, whereas the detection result of the light receiving element 221 illustrated in FIG. 10 includes the change in position and the change in angle. Both components are included. In view of such circumstances, theoretically, the feedback control by the control unit 300 is performed first by first performing angle control (control by the angle control means 330) for matching the angles, and then for matching the positions. It is preferable to perform position control (control by the position control means 310). If the detection result for the angle matches the reference value, the change component for the angle can be removed from the detection result of the light receiving element 221, and only the change component for the position can be recognized. In practice, however, if angle control and position control are executed alternately and repeatedly, feedback control that gradually brings the detection result closer to the reference value is performed. Need not be strictly considered.

  In the embodiment shown in FIG. 8, the angle detector 210 is disposed on the back side of the third mirror 30 to detect the angle (orientation) of the light beam L30 transmitted through the reflecting surface M3 and the fourth mirror. The position detecting means 220 is arranged on the back side of 40 and the position of the light beam L40 that has passed through the reflecting surface M4 (the amount of shift in translation) is detected. The arrangement of the angle detecting means 210 and the position detecting means 220 is as follows. You can replace it. That is, the position detecting means 220 is arranged on the back surface side of the third mirror 30 to detect the position of the light beam L30 transmitted through the reflecting surface M3 (shift amount of translation), and on the back surface side of the fourth mirror 40. The angle detection means 210 may be arranged at the position to detect the angle (direction) of the light beam L40 that has passed through the reflecting surface M4.

  In short, the output unit 200 includes a third mirror 30 that reflects the light beam L3 coming from the main body 100, and a fourth mirror 40 that reflects and emits the light beam L4 reflected from the third mirror 30. Furthermore, an angle detecting means 210 for detecting an incident angle of a light beam transmitted through one of the third mirror 30 and the fourth mirror 40 with respect to a predetermined reference plane, and a light beam transmitted through the other Position detecting means 220 for detecting the incident position on the predetermined reference plane may be provided.

It is a perspective view which shows arrangement | positioning of 2 sets of mirrors which comprise the optical system in the main-body part of the optical axis automatic adjustment system which concerns on one Embodiment of this invention. FIG. 3 is an XZ sectional view showing an optical axis change caused by translating a reflecting surface M1 in the X-axis direction in the optical system shown in FIG. FIG. 3 is an XZ sectional view showing an optical axis change caused by translating a reflecting surface M1 in the Z-axis direction in the optical system shown in FIG. FIG. 3 is a YZ sectional view showing an optical axis change caused by translating a reflecting surface M2 in the Z-axis direction in the optical system shown in FIG. FIG. 3 is a YZ sectional view showing an optical axis change caused by translating a reflecting surface M2 in the Y-axis direction in the optical system shown in FIG. FIG. 2 is an XZ sectional view showing an optical axis change caused by tilting the reflecting surface M1 in a direction in which the reflecting surface M1 rotates around an axis parallel to the Y axis through the incident point P1 in the optical system shown in FIG. FIG. 3 is a YZ cross-sectional view showing an optical axis change that occurs when the reflecting surface M2 is tilted in a direction to rotate around an axis parallel to the X axis through the incident point P2 in the optical system shown in FIG. It is a block diagram which shows the basic composition of the optical axis automatic adjustment system which concerns on one Embodiment of this invention. It is a top view which shows the principle of the angle detection by the angle detection means 210 shown in FIG. It is a top view which shows the principle of the position detection by the position detection means 220 shown in FIG.

Explanation of symbols

10: first mirror 11: axis parallel to Y axis 20: second mirror 21: axis parallel to X axis 30: third mirror 40: fourth mirror 100: main body 110: first support Body 120: Angle adjusting means 130: Position adjusting means 140: Second support 200: Output unit 210: Angle detecting means 211: Condensing lens 212: Light receiving element 220: Position detecting means 221: Light receiving element 300: Control part 310 : Position control means 320: Position storage means 330: Angle control means 340: Angle storage means L1, L2, L2 ', L3, L3', L4, L5: Light beams L30 to L43: Detection light beams M1, M1 ', M2, M2 ', M3, M4: Reflecting surface O: Origin P1, P1', P2, P2 'of coordinate system: Incident point Pi: Incident point Po: Ejection points Q31, Q33, Q41, Q42, Q43: Incident point α , Β: Angle δ: Inclination angle ΔLx DerutaLz: light beam displacement ΔM1x, ΔM1z: displacement ΔM2y of the reflecting surface M1, ΔM2z: displacement of the reflecting surface M2

Claims (4)

When a light beam is present along a reference optical path that passes through a predetermined incident point and an exit point in an XYZ three-dimensional coordinate system, even if the incident light deviates from the reference optical path, the emitted light follows the reference optical path. An optical axis automatic adjustment system having a function of performing automatic optical axis adjustment so as to maintain
A main body that performs optical axis adjustment, an output unit that emits light from the main body, and a control unit that controls an optical axis adjustment operation by the main body.
The main body is
A first mirror having a reflective surface obtained by rotating a plane parallel to the XY plane by a predetermined angle α (0 ° <α <90 °) about a rotation axis parallel to the Y axis;
A second mirror having a reflecting surface obtained by rotating a plane parallel to the XZ plane by a predetermined angle β (0 ° <β <90 °) about a rotation axis parallel to the X axis;
A support for supporting the first mirror and the second mirror at a predetermined position so that incident light is emitted toward the output unit after at least reflecting both of the mirrors in this order;
Position adjusting means for translating the first mirror in the X-axis or Z-axis direction with respect to the support, and translating the second mirror in the Y-axis or Z-axis direction;
A function of rotating the first mirror about a rotation axis parallel to the Y axis and an operation of rotating the second mirror about a rotation axis parallel to the X axis; Angle adjustment means;
Have
The output unit is
A third mirror for reflecting the light beam coming from the main body,
A fourth mirror that reflects and emits the light beam reflected by the third mirror;
An angle detection means for detecting an incident angle with respect to a predetermined reference plane of the light beam transmitted through one of the third mirror and the fourth mirror;
Position detecting means for detecting an incident position on a predetermined reference plane of a light beam transmitted through the other one of the third mirror and the fourth mirror;
Have
The controller is
Storage means for storing the angle and position detected by the angle detection means and the position detection means in a state where the incident light is along the reference optical path;
When the angle and position detected by the angle detection unit and the position detection unit deviate from the values stored in the storage unit, the angle adjustment unit and the position adjustment unit are controlled so as to eliminate the shift. Control means;
Have
The light incident on the output unit reflects only the third mirror and the fourth mirror and exits from the output unit. The first to fourth mirrors have a reflectance of 99.5% or more. An optical axis automatic adjustment system characterized by using a mirror . When a light beam is present along a reference optical path that passes through a predetermined incident point and an exit point in an XYZ three-dimensional coordinate system, even if the incident light deviates from the reference optical path, the emitted light follows the reference optical path. An optical axis automatic adjustment system having a function of performing automatic optical axis adjustment so as to maintain
A main body that performs optical axis adjustment, an output unit that emits light from the main body, and a control unit that controls an optical axis adjustment operation by the main body.
The main body is
A first mirror having a reflective surface obtained by rotating a plane parallel to the XY plane by a predetermined angle α (0 ° <α <90 °) about a rotation axis parallel to the Y axis;
A second mirror having a reflecting surface obtained by rotating a plane parallel to the XZ plane by a predetermined angle β (0 ° <β <90 °) about a rotation axis parallel to the X axis;
A first support that supports the first mirror and the second mirror at a predetermined position so that incident light is emitted toward the output unit after reflecting at least both of the mirrors in this order. When,
A second support for supporting the first support;
Position adjusting means for translating the first support relative to the second support in the X-axis direction and the Y-axis direction;
A function of rotating the first mirror about a rotation axis parallel to the Y axis and an operation of rotating the second mirror about a rotation axis parallel to the X axis; Angle adjustment means;
Have
The output unit is
A third mirror for reflecting the light beam coming from the main body,
A fourth mirror that reflects and emits the light beam reflected by the third mirror;
An angle detection means for detecting an incident angle with respect to a predetermined reference plane of the light beam transmitted through one of the third mirror and the fourth mirror;
Position detecting means for detecting an incident position on a predetermined reference plane of a light beam transmitted through the other one of the third mirror and the fourth mirror;
Have
The controller is
Storage means for storing the angle and position detected by the angle detection means and the position detection means in a state where the incident light is along the reference optical path;
When the angle and position detected by the angle detection unit and the position detection unit deviate from the values stored in the storage unit, the angle adjustment unit and the position adjustment unit are controlled so as to eliminate the shift. Control means;
Have
The light incident on the output unit reflects only the third mirror and the fourth mirror and exits from the output unit. The first to fourth mirrors have a reflectance of 99.5% or more. An optical axis automatic adjustment system characterized by using a mirror . The optical axis automatic adjustment system according to claim 1 or 2,
The angle detection means has a condensing lens for condensing parallel rays at a predetermined focal point, and a condensing position on the light receiving surface, the light receiving surface being disposed at a focal distance from the condensing lens. An optical axis automatic adjustment system comprising: a light receiving element for detecting light. The optical axis automatic adjustment system according to any one of claims 1 to 3,
An automatic optical axis adjustment system characterized in that the position detecting means is constituted by a light receiving element for detecting a beam irradiation position on a predetermined light receiving surface.

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