JP2005241607A - Apparatus for measuring angle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To precisely measure the inclination of an object to be measured, having a non-flat plane in an angle measuring apparatus for measuring the inclination angle of the object to be measured. <P>SOLUTION: Light, emitted from a laser light source 10, is made to diverge by a divergent lens 20, and the beams at the center of optical fluxes of diverged beams are made to pass through the light-transmitting hole 30A of an apertured plate 30. Then, parallel beams transformed through a collimator lens 40 are irradiated to a lens L having an annular flat-surface section F. It is arranged so that the direction from a light-branching means is different from that of an imaging means, and also that a light-receiving means 100 for receiving the light with a beam diameter varied by a beam radius varying means and a display means 110. The display means 110 is formed to display the beam diameter information, corresponding to the beam diameter of the light varied by the beam radius varying means, based on the received light signals from light-receiving means 100. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an angle measuring device.

2. Description of the Related Art Conventionally, there is a so-called autocollimator as an angle measuring apparatus for optically measuring an inclination angle, flatness, surface roughness, etc. in a test object such as a disk such as a CD or DVD, a plate glass, or a mirror surface. For example, as shown in Patent Document 1, light emitted from a light source is converted into parallel light by a collimator lens and projected onto a surface to be measured of a measurement target, and reflected light from the surface to be measured is again reflected on the collimator lens. The spot image formed on the image pickup means is observed by the image pickup means condensed by the collimator lens and arranged near the focal position.
Japanese Patent No. 2748175 JP 2001-324314 A

  On the other hand, in the past, there has been proposed one having a function (so-called projection diameter aperture function) capable of changing the beam diameter of parallel light irradiated onto the measurement surface according to the size of the measurement object. There is something as shown in Patent Document 2. However, even with the configuration having the aperture function described above, the light emission amount of the visible wavelength semiconductor laser used for the light source of the autocollimator is dark light that cannot be visually recognized by the operator. It is difficult to change the beam diameter.

  Even if the spot on the irradiated surface is made easily visible by increasing the light emission amount of the semiconductor laser, the operator must change the beam diameter while looking at the spot. The work is unavoidable, and there are problems with workability and accuracy. In particular, in the autocollimator, the original beam diameter itself may be thin, and there are many cases where the difference in diameter is not known at the worker's visual recognition level, so the beam diameter cannot be set or grasped accurately.

  The present invention has been made based on the above circumstances, and an object thereof is to provide a configuration in which a user can accurately grasp a beam diameter.

As a means for achieving the above object, the invention of claim 1 is directed to directing light from the light projecting means by one of transmission and reflection through the light branching means and into parallel light through the collimator lens. The parallel light is converted to irradiate the object to be measured, and the reflected light from the object to be measured is transmitted from the light branching means through the light branching means to the light from the light projecting means. Branch in another direction and focus on the image pickup surface of the image pickup means, and measure the inclination of the object to be measured based on the image pickup signal from the image pickup means output according to the position of the light collection spot on the image pickup surface. An angle measuring device comprising a calculating means for performing
A beam diameter that is arranged on the front side of the light branching unit in the light projecting path between the light projecting unit and the light branching unit and that changes the beam diameter of the parallel light emitted through the collimator lens. Variable means;
A light receiving means that is arranged so that the direction from the light branching means is different from the imaging means, and that directly receives the light after the beam diameter is changed by the beam diameter varying means;
Display means,
The light branching unit is configured to guide the light from the light projecting unit to the light receiving unit by the other of transmission and reflection,
The display means displays beam diameter information corresponding to the beam diameter of the light after the beam diameter has been changed by the beam diameter varying means based on the light reception signal from the light receiving means.

According to the second aspect of the invention, the light from the light projecting means is guided by one of transmission and reflection through the light branching means, and converted into parallel light through the collimator lens, and the parallel light is measured. The imaging means irradiates an object and branches the reflected light from the object to be measured in the direction different from the light from the light projecting means by the other of transmission and reflection through the light branching means. An angle measuring device comprising a computing means for focusing on a surface and measuring an inclination of the object to be measured based on an imaging signal from the imaging means that is output according to a focused spot position on the imaging surface. ,
A beam diameter that is arranged on the front side of the light branching unit in the light projecting path between the light projecting unit and the light branching unit and that changes the beam diameter of the parallel light emitted through the collimator lens. Variable means;
Beam diameter setting means for setting the beam diameter;
Storage means for storing level specifying information for specifying a reference level corresponding to a beam diameter that can be set by the beam diameter setting means;
Based on the light reception signal from the light receiving means and the level specifying information, a reference level corresponding to the beam diameter set by the beam diameter setting means is acquired, and the reference level and the light reception signal from the light receiving means are obtained. Control means for controlling the beam diameter varying means so as to vary the beam diameter so that the corresponding levels coincide with each other is provided.

According to a third aspect of the present invention, in the angle measurement device according to the second aspect, the light receiving means includes a plurality of elements arranged in a single row or in a two-dimensional shape,
The reference level is a reference beam diameter;
The control means includes
Based on the light reception signal from the light receiving means and the level specifying information, a reference beam diameter corresponding to the beam diameter set by the beam diameter setting means is acquired, and the acquired reference beam diameter and the plurality The beam diameter is varied by the beam diameter varying means so that the beam diameter calculated from the received light signal from the imaging element matches.

According to a fourth aspect of the present invention, in the angle measuring device according to any one of the first to third aspects, a correction for specifying a correction coefficient corresponding to a beam diameter that can be set by the beam diameter setting means. Correction coefficient information storage means for storing coefficient information;
The control means varies the beam diameter varying means based on a light reception signal from the light receiving means, and stores a correction coefficient corresponding to the beam diameter set by the setting means in the correction coefficient information storage means. Obtained based on the correction coefficient information
The computing means is
When calculating the inclination of the object to be measured from the imaging signal output according to the condensing spot position on the imaging surface of the imaging means, the object to be measured is corrected and calculated by the read correction coefficient. It is characterized by measuring the slope of the.

The invention according to claim 5 is the angle measuring device according to any one of claims 1 to 4,
The light projecting means is configured to emit linearly polarized light,
The light branching means comprises a polarizing beam splitter,
Further, a light projecting and rotating means for rotatably supporting the light projecting means about the optical axis,
Mode switching means capable of switching between a beam diameter adjustment mode for adjusting the beam diameter and a measurement mode for performing measurement;
When the beam diameter adjustment mode is set, the polarization direction of linearly polarized light emitted from the light projecting unit is set to the first polarization direction guided to the light receiving unit via the polarization beam splitter. When the projection rotation means is controlled and set to the measurement mode, the polarization direction is different from the first polarization direction, and the second polarization direction is guided to the imaging means via the polarization beam splitter. Rotation control means for controlling so that
It is provided with.

<Invention of Claim 1>
According to the configuration of claim 1, the operator can accurately grasp the beam width. Therefore, for example, during the adjustment work, the operator can perform adjustment while constantly grasping the accurate beam width by looking at the displayed beam width information, and the workability and convenience of the adjustment work can be improved. .

<Invention of Claim 2>
According to the configuration of the second aspect, it is possible to automatically set the desired beam width accurately, and the convenience can be further improved.

<Invention of Claim 3>
According to the configuration of the third aspect, by measuring the beam diameter, the beam diameter can be finely adjusted more accurately than in the case where it is obtained indirectly from the amount of received light.

<Invention of Claim 4>
According to the configuration of the fourth aspect, even when the profile of the light receiving spot changes according to the beam diameter, it can be appropriately processed.

<Invention of Claim 5>
According to the structure of Claim 5, appropriate control according to each mode is attained in each of the measurement mode and the beam diameter adjustment mode.

<Embodiment 1>
An embodiment of an angle measuring apparatus 1 according to the present invention will be described with reference to FIGS. 1 and 2. This angle measuring device includes a laser light source 10 (the laser light source 10 corresponds to a light projecting unit in the claims), a diverging lens 20, and an aperture plate 30 having a light passage hole 30A (the aperture plate is a beam diameter variable unit). (Specifically, it can be configured by a pinhole plate, a slit plate, etc.), a collimator lens 40, a beam splitter 50 (the beam splitter 50 corresponds to the light branching means in the claims), and convergence. A lens 60, a two-dimensional CCD 70 (the two-dimensional CCD 70 corresponds to the imaging means in the claims), and a CPU 80 are provided.

  The light emitted from the laser light source 10 is made divergent light by the diverging lens 20, and part of this divergent light passes through the light passage hole 30 </ b> A of the aperture plate 30 and is made parallel light by the collimator lens 40. Then, the parallel light is reflected by the beam splitter 50 and is emitted to the outside of the apparatus, and is irradiated onto the workpiece W (the workpiece W corresponds to an object to be measured in the claims). Reflected light from the work W enters the apparatus and is collected by the converging lens 60 via the beam splitter 50 to form a light receiving spot on the imaging surface of the CCD 70. The CCD 70 outputs to the CPU 80 an imaging signal composed of a digital signal sequence based on the amount of light received by each pixel constituting the imaging surface. For example, the distance between the aperture plate 30 and the collimator lens 40 is adjusted so that the beam diameter of the parallel light from the collimator lens 40 is larger than the surface of the workpiece W where the light is irradiated.

  The CPU 80 detects the tilt angle of the workpiece W based on the imaging signal received from the CCD 70. As a specific detection method, for example, the condensing spot position on the imaging surface when it is assumed that the workpiece W is not inclined is preferably set to the reference position (preferably the center of the imaging surface), and the condensing spot position at the time of measurement. The tilt angle is detected from the distance between the reference position and the reference position. By the way, since it is general that the light receiving spot is formed over a plurality of pixels, in practice, one of the pixels constituting the light receiving spot is representatively determined as the center of the light receiving spot, and the above method is used. The tilt angle is measured with. As the determination method of the center of the light receiving spot, the area centroid position or the volume centroid position on the imaging surface is obtained, and the pixel corresponding to this centroid position is set as the center of the light receiving spot, and the pixel having the maximum light receiving amount is There is a method of determining the center of the light receiving spot, and either method may be used. Instead of using the method in which the pixel corresponding to the barycentric position is the center of the light receiving spot as described above or the method of determining the pixel having the maximum light receiving amount as the center of the light receiving spot, the barycentric position is geometrically determined. It may be calculated. That is, the area centroid position or the volume centroid position on the imaging surface is obtained and the position is determined as it is as the center of the light receiving spot (that is, the pixel position that approximates the centroid position is not determined as the center of the light receiving spot, but is calculated. The area centroid position or volume centroid position value may be used as it is).

  The laser light source 10, the diverging lens 20, the aperture plate 30, and the collimator lens 40 are arranged as follows. That is, the optical axis of the light emitted from the laser light source 10, the central axis of the diverging lens 20, the central axis of the light passage hole 30 </ b> A, and the central axis of the collimator lens 40 are arranged to coincide with each other. The laser light source 10 is arranged so that the optical axis of the emitted light coincides with the central axis.

  In the present embodiment, the collimator is disposed on the front side (laser light source 10 side) of the beam splitter 50 in the light projecting path between the laser light source 10 (light projecting unit) and the beam splitter 50 (light branching unit). The beam diameter of the parallel light emitted through the lens 40 can be varied by the aperture plate 30. That is, the beam diameter of the parallel light is changed as a result by exchanging the aperture plates 30 having different hole diameters.

  Further, in the present embodiment, the light receiving means 100 is arranged so that the direction from the beam splitter 50 is different from the image pickup means 70, and the beam diameter is changed by the aperture plate 30 (beam diameter varying means). It is configured to receive the light after. The beam splitter 50 is configured to guide the light from the laser light source 10 to the light receiving means 100 by transmission, and the beam diameter is changed by the aperture plate 30 (beam diameter varying means) based on the light receiving signal from the light receiving means 100. The display means 110 displays beam diameter information corresponding to the beam diameter of the subsequent light. As the beam diameter information, the value of the beam diameter may be displayed, or a level corresponding to the beam diameter may be displayed.

  In the present embodiment, a beam diameter setting means may be provided and the beam diameter may be varied by control. For example, a mechanism that automatically changes a plurality of aperture plates 30 based on input from an operator (for example, a plurality of aperture plates driven by an actuator based on input from an input means (not shown) connected to the CPU 80). When a mechanism that automatically changes 30 (or a mechanism in which a plurality of holes having different diameters are provided in the same plate and the plate is displaced by driving the actuator to change the hole to be used) is configured, The input means corresponds to the beam diameter setting means, and in the configuration in which the lens diameter is set by moving the lens as shown in Fig. 7 (described later), the lens movement amount (or information corresponding thereto) is input. 7 is equivalent to the beam diameter setting means (for example, the input means connected to the CPU 80 of FIG. 7). The CPU 80, which is a control unit, has correction coefficient information storage means (for example, a ROM (not shown) connected to the CPU 80) for storing correction coefficient information for specifying the correction coefficient corresponding to the beam diameter that can be determined. The correction coefficient corresponding to the beam diameter set by the beam diameter setting means as described above is acquired based on the correction coefficient information stored in the correction coefficient information storage means, and the CPU 80 as the calculation means captures the image of the imaging means 70. When calculating the inclination of the object to be measured from the imaging signal output according to the position of the focused spot on the surface, the inclination of the object to be measured is measured by performing correction calculation using the read correction coefficient. It is configured.

  For example, as shown in FIG. 3, threshold level information corresponding to a range of diameters that can be set by the beam diameter setting means as the correction coefficient is prepared as correction coefficient information, and the tilt is calculated from the imaging signal. The calculation can be performed using an appropriate threshold level corresponding to the received light signal. Further, as shown in FIG. 3B, a detection area size corresponding to the diameter range (that is, corresponding to the set diameter range) is prepared as a correction coefficient, and appropriate detection according to the light reception signal is prepared. An operation can be performed using the size of the region. Here, an example is shown in which correction coefficient information such as a threshold level corresponding to the diameter range and the size of the detection area is stored as a table, and correction coefficient information corresponding to the beam diameter is stored as correction coefficient information storage means (ROM). Etc.), the correction coefficient information may be other information as long as it is information that can specify the correction coefficient corresponding to the diameter. For example, a correction formula for calculating a correction coefficient using a beam diameter as a parameter (for example, a correction formula for calculating a threshold level according to the beam diameter or a correction formula for calculating the size of the detection region according to the beam diameter) is corrected. A configuration may be used in which the correction coefficient is calculated based on the beam diameter by being stored in the storage unit as coefficient information.

The configuration of the present embodiment is as described above, and the operation thereof will be described below.
The light emitted from the laser light source 10 is converted into parallel light as described above and applied to the workpiece W, and the reflected light is applied to the imaging surface of the CCD 70 via the beam splitter 50 and the condenser lens 60 to receive the light receiving spot. Form. Then, the CPU 80 measures the tilt angle of the workpiece W based on the imaging signal from the CCD 70.

  Now, the distribution of light intensity I (hereinafter referred to as light intensity distribution) on the A-axis (axis orthogonal to the optical axis LC) of the parallel light irradiated onto the workpiece W is substantially uniform as shown in the lower part of FIG. Has been. This is realized by diverging the light from the laser light source 10 by the diverging lens 20 and passing the light of the optical axis portion (light of the light flux center portion) of the divergent light through the light passage hole 30A. The process until the light intensity distribution of parallel light is made uniform is shown.

The intensity distribution of light emitted from the laser light source 10 is generally Gaussian as shown in FIG. Since the light from the laser light source 10 is diverged by the diverging lens, the light intensity distribution is stretched in the direction orthogonal to the optical axis LC, and the peak region of the light intensity I is widened (part (1) in FIG. 1, (See FIG. 2A). Of the diverging light, only the light having the peak light intensity I (the region indicated by A in the drawing) is passed through the light passage hole 30A, so that the intensity distribution of the light that has passed through the light passage hole 30A is substantially uniform. (See part (2) in FIG. 1, FIG. 2 (B)). Therefore, even if this diverging light is passed through the collimator lens 40, the light intensity I is kept uniform and is made into parallel light (see part (3) in FIG. 1, FIG. 2C).
In the present embodiment, the aperture plate 30 causes the light from the laser light source 10 (light projecting element) to pass the light at the optical axis (light at the center of the light beam) through the light passage hole 30A and enter the collimator lens 40. The other light is blocked by the aperture plate 30 and prohibited from entering the collimator lens. This is because the light intensity distribution of the emitted parallel light is biased when light other than the light on the optical axis (light at the center of the light beam) enters the collimator lens 40, and an aperture plate is used to prevent this. It is necessary to block light other than light in the optical axis portion by 30.

  Here, when the workpiece W is the optical pickup lens L shown in the description of the prior art, the parallel light emitted from the apparatus is irradiated on the entire lens L having the annular flat surface portion F and reflected from the annular flat surface portion F. A light receiving spot is formed on the imaging surface of the CCD 70 by the light. At this time, regardless of whether or not the optical axis LC of the parallel light and the central axis of the lens L coincide with each other, light is evenly applied to each portion of the annular flat surface portion F. Therefore, if the lens L is in a horizontal state, the pixel at the reference position on the imaging surface is determined as the light receiving spot, and therefore the inclination angle is determined to be 0 °. Further, when the lens L is tilted, the light receiving spot on the imaging surface is shifted from the reference position, so the tilt angle is measured based on the amount of shift.

  In order to obtain the beam diameter information by the light receiving means 100, the beam diameter is obtained from the width information or the received light quantity information of the light incident on the light receiving means 100 without using the condenser lens as shown in FIG. Alternatively, as shown in FIG. 4, it may be configured to enter the light receiving means 100 via the condenser lens 102, and the beam diameter may be obtained based on the received light amount level.

<Embodiment 2>
Next, Embodiment 2 will be described with reference to FIGS.
In the second embodiment, the laser light source 10 as the light projecting unit is configured to emit linearly polarized light, and the light branching unit is configured by the polarization beam splitter 80. And the light projection rotation means M (for example, stepping motor etc.) which supports the laser light source 10 rotatably around the optical axis LC is provided. This configuration is configured to be switchable between a beam diameter adjustment mode for adjusting the beam diameter and a measurement mode for performing measurement based on, for example, user input. In this embodiment, the CPU 80 performs mode switching by an input unit (not shown) connected to the CPU 80, and the CPU 80 corresponds to the mode switching unit.

  When the beam diameter adjustment mode is set, the polarization direction of the linearly polarized light emitted from the laser light source 10 becomes the first polarization direction guided to the light receiving means 100 via the polarization beam splitter 80 (see FIG. 6), when the projection rotation means M is controlled and set to the measurement mode, the second polarized light guided to the imaging means 70 via the polarization beam splitter 80 whose polarization direction is different from the first polarization direction. Control is performed so as to be in the direction (see FIG. 5). The CPU 80 corresponds to the rotation control means in the claims. A quarter-wave plate 82 is provided between the polarizing beam splitter 80 and the workpiece W, and is changed to circularly polarized light so as to irradiate, for example, the mirror-like workpiece W.

<Embodiment 3>
Next, Embodiment 3 will be described with reference to FIG.
In the third embodiment, parallel light emitted through a collimator lens (condensing lens 92) is disposed on the near side of the beam splitter 50 in the light projecting path between the laser light source 10 and the beam splitter 50. Condensing lenses 91 and 92 are provided as beam diameter changing means for changing the beam diameter, and either one or both of them can be displaced in the optical axis direction. The displacing lens corresponds to the beam diameter varying means. When the condenser lens 91 is displaced, it corresponds to the condenser lens 91 beam diameter varying means. When the condenser lens 92 is displaced, this is equivalent to this. This corresponds to a beam diameter varying means. When both lenses 91 and 92 are made into one piece, both lenses 91 and 92 are equivalent to a beam diameter variable means. The condensing lens 92 corresponds to a collimator lens in the claims.

  The beam diameter can be set by beam diameter setting means (for example, input means not shown). Here, input means (for example, input means (not shown) connected to the CPU 80 in FIG. 7) for inputting the lens movement amount (or information corresponding thereto) corresponds to the beam diameter setting means. Storage means (such as a ROM (not shown) connected to the CPU 80) for storing level specifying information for specifying a reference level corresponding to the beam diameter that can be set by the beam diameter setting means is provided.

  In the present embodiment, a reference level corresponding to the beam diameter set by the beam diameter setting unit is acquired based on the light reception signal from the light receiving unit 100 and the level specifying information, and the reference level and the light reception from the light receiving unit 100 are obtained. Control is performed to vary the beam diameter with respect to the beam diameter varying means (lenses 91 and / or 92) so that the level according to the signal matches. That is, drive control of one or both of the condenser lenses 91 and 92 is performed.

In the present embodiment, the light receiving means 100 is composed of a plurality of elements (for example, a one-dimensional CCD or a two-dimensional CCD) arranged in a line or two-dimensionally, and a reference beam diameter is adopted as the reference level. ing. Specifically, based on the light reception signal from the light receiving means 100 and the level specifying information, a reference beam diameter corresponding to the beam diameter set by the beam diameter setting means is acquired, and the acquired reference beam diameter and The beam diameter is varied by the beam diameter varying means so that the beam diameters calculated from the light reception signals from the plurality of image sensors coincide with each other. In FIG. 8, information defining a reference beam diameter (a beam diameter serving as a reference when the beam diameter is changed and corresponding to a reference level) corresponding to the beam diameter is stored as level specifying information as a table. An example is shown. FIG. 8 illustrates a configuration in which the reference beam diameter corresponding to the beam diameter is acquired by a storage unit (ROM or the like). However, the level specifying information may be information that can specify the reference level corresponding to the diameter. Other information may be used. For example, a correction formula for calculating a reference level using a beam diameter as a parameter (for example, a correction formula for calculating a reference beam diameter according to a set beam diameter, or a reference received light amount according to a set beam diameter) The correction formula) may be stored in the storage means as reference level information, and the reference level may be calculated based on the beam diameter.
Also in this embodiment, as shown in FIG. 3, as in the first embodiment, threshold level information corresponding to the diameter range set by the beam diameter setting means is prepared as correction coefficient information. In addition, when calculating the inclination from the imaging signal, the calculation can be performed using an appropriate threshold level corresponding to the received light signal. Further, as shown in FIG. 3B, a detection area size corresponding to the diameter range set as the correction coefficient is prepared, and calculation is performed using an appropriate detection area size corresponding to the light reception signal. Can be. Here, an example is shown in which correction coefficient information such as a threshold level corresponding to the diameter range and the size of the detection area is stored as a table, and correction coefficient information corresponding to the beam diameter is stored as correction coefficient information storage means (ROM). Etc.), the correction coefficient information may be other information as long as it is information that can specify the correction coefficient corresponding to the diameter. For example, a correction formula for calculating a correction coefficient using a beam diameter as a parameter (for example, a correction formula for calculating a threshold level according to the beam diameter or a correction formula for calculating the size of the detection region according to the beam diameter) is corrected. A configuration may be used in which the correction coefficient is calculated based on the beam diameter by being stored in the storage unit as coefficient information.

<Other embodiments>
The present invention is not limited to the embodiments described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention, and further, within the scope not departing from the gist of the invention other than the following. Various modifications can be made.
(1) Although the example applied to the measurement of the tilt of the optical pickup lens of the optical pickup device has been described in the above embodiment, it can also be used to measure the tilt of other things.

  (2) In the first embodiment, the beam diameter is changed by the aperture plate. However, for example, beam diameter changing means having an iris diaphragm structure may be used.

(3) In the first embodiment, the aperture plate 30 serving as the beam diameter varying means is disposed on the front side of the collimator lens 30 (on the light projecting element side in the light projecting path). However, as shown in FIG. The configuration may be such that 40 is arranged on the near side and the beam diameter is changed after the parallel light is made.
(4) In the first embodiment, the collimator lens 40 is disposed between the laser light source 10 and the beam splitter 50 in the light projecting path. However, the light reflected from the beam splitter as shown in FIG. The collimator lens 40 may be arranged as described above. In FIG. 10, the light whose diameter has been set by the beam diameter varying means is reflected by the beam splitter 50 and is incident on the collimator lens 40. After being converted into parallel light, it is incident on the workpiece. The light reflected from the work is similarly incident on the collimator lens 40, collected by the collimator lens 40, and incident on the imaging means 70. On the other hand, the light that is varied by the beam diameter varying means and transmitted through the beam splitter 50 passes through the condenser lens 104 to the light receiving means 10 as parallel light having a width corresponding to the beam diameter varied by the beam diameter varying means. Incident. A condensing lens may be further provided between the condensing lens 104 and the light receiving unit 100 so that the condensed light is incident on the light receiving unit 100.

The conceptual diagram which illustrates notionally the angle measuring device which concerns on Embodiment 1 of this invention. (A) The figure which showed light intensity distribution of the light irradiated to the aperture plate (B) The figure which showed light intensity distribution of the light which passed the light passage hole (C) The light intensity distribution of the light which permeate | transmitted the collimator lens Illustration shown Explanatory drawing which illustrates notionally composition of amendment storage means The conceptual diagram which illustrates notionally the angle measuring device which concerns on Embodiment 2 of this invention. The conceptual diagram which illustrates conceptually the angle measuring device which concerns on Embodiment 3 of this invention. Diagram showing the state when the polarization direction is changed The conceptual diagram which illustrates notionally the angle measuring device which concerns on Embodiment 4 of this invention. Explanatory drawing explaining the memory | storage structure of a memory | storage means notionally The figure which shows the example which changes a beam diameter, after making it parallel light with a collimator lens The figure which illustrates the structure which varied the positional relationship of a collimator lens and an optical branching means with respect to FIG. 1, FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Angle measuring device 10 ... Laser light source (light projection means)
30 ... aperture plate (beam diameter variable means)
40 ... Collimator lens 50 ... Beam splitter (light splitting means)
70: CCD (imaging means)
80 ... CPU (calculation means, control means)
DESCRIPTION OF SYMBOLS 100 ... Light receiving means 110 ... Display means W ... Workpiece (object to be measured)

Claims (5)

The light from the light projecting means is guided by one of transmission and reflection through the light branching means, converted into parallel light through the collimator lens, and irradiated with the parallel light on the object to be measured. The reflected light from the object to be measured is branched in the direction different from the light from the light projecting means by the other of transmission and reflection through the light branching means, and condensed on the imaging surface of the imaging means. An angle measuring device comprising a calculating means for measuring an inclination of the object to be measured based on an imaging signal from the imaging means that is output according to a condensing spot position on an imaging surface,
A beam diameter that is arranged on the front side of the light branching unit in the light projecting path between the light projecting unit and the light branching unit and that changes the beam diameter of the parallel light emitted through the collimator lens. Variable means;
A light receiving means that is arranged so that the direction from the light branching means is different from the imaging means, and that directly receives the light after the beam diameter is changed by the beam diameter varying means;
Display means,
The light branching unit is configured to guide the light from the light projecting unit to the light receiving unit by the other of transmission and reflection,
The angle measuring apparatus according to claim 1, wherein the display means displays beam diameter information corresponding to the beam diameter of the light after the beam diameter is changed by the beam diameter varying means based on the light reception signal from the light receiving means. The light from the light projecting means is guided by one of transmission and reflection through the light branching means, converted into parallel light through the collimator lens, and irradiated with the parallel light on the object to be measured. The reflected light from the object to be measured is branched in the direction different from the light from the light projecting means by the other of transmission and reflection through the light branching means, and condensed on the imaging surface of the imaging means. An angle measuring device comprising a calculating means for measuring an inclination of the object to be measured based on an imaging signal from the imaging means that is output according to a condensing spot position on an imaging surface,
A beam diameter that is arranged on the front side of the light branching unit in the light projecting path between the light projecting unit and the light branching unit and that changes the beam diameter of the parallel light emitted through the collimator lens. Variable means;
Beam diameter setting means for setting the beam diameter;
Storage means for storing level specifying information for specifying a reference level corresponding to a beam diameter that can be set by the beam diameter setting means;
Based on the light reception signal from the light receiving means and the level specifying information, a reference level corresponding to the beam diameter set by the beam diameter setting means is acquired by the storage means, and the reference level and the light receiving means are obtained. An angle measuring apparatus comprising: control means for controlling the beam diameter varying means so as to vary the beam diameter so that the level according to the received light signal from the same coincides. The light receiving means is composed of a plurality of elements arranged in a line or two dimensions,
The reference level is a reference beam diameter;
The control means includes
Based on the light reception signal from the light receiving means and the level specifying information, a reference beam diameter corresponding to the beam diameter set by the beam diameter setting means is acquired, and the acquired reference beam diameter and the plurality 3. The angle measuring device according to claim 2, wherein the beam diameter is varied by the beam diameter varying means so that the beam diameter calculated from the received light signal from the imaging element matches. Correction coefficient information storage means for storing correction coefficient information for specifying a correction coefficient corresponding to a beam diameter that can be set by the beam diameter setting means;
The control means varies the beam diameter varying means based on a light reception signal from the light receiving means, and a correction coefficient corresponding to the beam diameter set by the beam diameter setting means is stored in the correction coefficient information storage means. Obtained based on the stored correction coefficient information,
The computing means is
When calculating the inclination of the object to be measured from the imaging signal output according to the condensing spot position on the imaging surface of the imaging means, the object to be measured is corrected and calculated by the read correction coefficient. The angle measuring device according to claim 2, wherein the angle is measured. The light projecting means is configured to emit linearly polarized light,
The light branching means comprises a polarizing beam splitter,
Further, a light projecting and rotating means for rotatably supporting the light projecting means about the optical axis,
Mode switching means capable of switching between a beam diameter adjustment mode for adjusting the beam diameter and a measurement mode for performing measurement;
When the beam diameter adjustment mode is set, the polarization direction of linearly polarized light emitted from the light projecting unit is set to the first polarization direction guided to the light receiving unit via the polarization beam splitter. When the projection rotation means is controlled and set to the measurement mode, the polarization direction is different from the first polarization direction, and the second polarization direction is guided to the imaging means via the polarization beam splitter. Rotation control means for controlling so that
The angle measuring device according to any one of claims 1 to 4, further comprising:

Images