JP2005300478A - Optical measuring apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical measuring apparatus precisely measuring the angle and the distance of an object to be measured. <P>SOLUTION: The optical measuring apparatus mainly comprises a laser light source 11 for measuring an angle, an imaging element 12 for measuring an angle, a laser driving circuit 13, a laser light source 21 for measuring a distance, an imaging element 22 for measuring a distance, a laser driving circuit 23, and a CPU 4, and calculates the angle and the distance of a work W, based on the output signals Sc, Sd from the imaging element 12 and the imaging element 22. The CPU 4 automatically adjusts the increase and decrease of projection quantity of light irradiated from the laser light source 21 within a range less than an upper limit, in response to the projection quantity of the imaging element 22. Thus a light-receiving level is stabilized, and the laser light source 21 does not have an influence on the imaging element 12 due to the excessive increase of the projection quantity. Then, precise measurement of the distance and the angle of the work W is performed. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an optical measuring device.

The thing of patent document 1 is disclosed as an optical measuring apparatus which measures the distance and inclination of a to-be-measured object.
This system measures the distance and inclination of an object to be measured using the principle of triangulation, and includes a distance measuring optical system and an inclination measuring optical system. In the displacement measuring optical system, the light from the light projecting element converged by the lens is projected obliquely onto the object to be measured, and the reflected light is converged by the lens to form an image on the imaging surface of the imaging means. The distance of the object to be measured can be measured from the imaging position on the imaging surface.
In addition, the tilt measurement optical system projects light from the light projecting element, which has been collimated by the lens, onto the object to be measured from an oblique direction, and the reflected light is converged by the lens to be connected to the imaging surface of the imaging means. The inclination of the object to be measured can be measured based on the imaging position on the imaging surface.
JP-A-8-240408

The above structure has two independent light sources. In this case, there are a method of separately irradiating light from the light source and individually acquiring data on the angle and distance with a time difference, and a method of simultaneously acquiring light and light on the angle and distance from the light source. However, the method of acquiring data at the same time is more reliable in measurement. However, since the light emitted from the light source is repeatedly reflected and attenuated, for example, the reflected light of the light emitted from the light source on one side may enter the imaging means on the other side. In particular, when the distance is calculated after performing the predetermined correction after calculating the angle in advance, the error cannot be ignored if the light from the distance light source enters the imaging means for angle measurement.
The present invention has been completed based on the above situation, and an object thereof is to provide an optical diameter measuring apparatus capable of accurately measuring the distance and angle of an object to be measured.

As a means for achieving the above object, the invention of claim 1 is an optical measuring apparatus for irradiating a measurement object with light and measuring the inclination and distance of the measurement object based on the reflected light. A light guiding means for guiding light from the angle measuring light projecting means to the object to be measured, an angle measuring imaging means, and the angle measuring reflected light reflected by the object to be measured; and Condensing means for guiding to an imaging surface provided in the imaging means for angle measurement;
Distance measuring light projecting means capable of irradiating light from a direction inclined by a predetermined angle with respect to the object to be measured, and adjusting means capable of adjusting the light projecting amount of light irradiated from the distance measuring light projecting means The distance measurement reflected light that is irradiated from the distance measurement light projecting means and reflected by the object to be measured can be imaged at the same timing as the angle measurement imaging means images the angle measurement reflected light. Distance of the object to be measured based on output signals relating to the reflected light for angle measurement and the reflected light for distance measurement obtained from the imaging means for distance measurement, the imaging means for angle measurement, and the imaging means for distance measurement, respectively. And calculating means for calculating the angle, and the light emitted from the distance measuring light projecting means according to the amount of light received from the distance measuring imaging means prior to the calculation of the distance and angle by the calculating means. The control means for controlling the adjustment means so that the received light amount becomes a predetermined reference light reception level by increasing / decreasing the light quantity, and the light projection quantity of light emitted from the distance measuring light projection means by the adjustment means The increase / decrease adjustment is characterized by comprising an upper limit value setting means for determining an upper limit value of the light emission amount.

  The invention of claim 2 is an optical measuring device for irradiating light to the object to be measured and measuring the inclination and distance of the object to be measured based on the reflected light, and the light from the angle measuring light projecting means On the imaging surface provided to the angle measurement imaging means, and to collect the angle measurement reflected light reflected by the measurement object. Condensing means for guiding, distance measuring light projecting means capable of irradiating light from a direction inclined by a predetermined angle with respect to the object to be measured, and light projecting amount of light irradiated from the distance measuring light projecting means Adjustable adjustment means and distance measurement reflected light emitted from the distance measurement light projecting means and reflected by the object to be measured are the same as when the angle measurement imaging means images the angle measurement reflected light. Distance measuring imaging means capable of imaging at the timing, and the angle measurement; Calculating means for calculating the distance and angle of the object to be measured based on output signals relating to the reflected light for angle measurement and the reflected light for distance measurement respectively obtained from the imaging means for distance measurement and the imaging means for distance measurement; It is determined whether or not the distance calculated by the calculating means is within a predetermined range, and when the object to be measured is outside the predetermined range, the light projection from the distance measuring light projecting means is stopped, or It is characterized by comprising control means for controlling the adjusting means so as to reduce the light.

  Here, the predetermined range is a measurement related to the angle of the object to be measured even if the light emitted from the distance measuring light projecting means or the reflected light does not enter the angle measuring imaging means or is incident. The range does not affect the accuracy.

  According to a third aspect of the present invention, in the first aspect of the present invention, when the object to be measured is outside a predetermined range, the control means performs the light projection from the distance measuring light projecting means in the second aspect. It is characterized in that it is controlled to stop or dimm.

<Invention of Claim 1>
According to the first aspect of the present invention, since the light projection amount of the light emitted from the distance measurement light projecting unit is increased or decreased according to the amount of received light, a stable output can be obtained from the distance measurement image sensor. Therefore, the measurement reliability is excellent.
In addition, when performing such increase / decrease control of the light projection amount, there is a concern about the influence on the imaging device for angle measurement accompanying the increase of the light projection amount of the distance measurement light projection unit. Since it is performed in a range not exceeding the upper limit value, the light from the distance measuring light projecting means does not affect the angle measuring imaging means.

<Invention of Claim 2>
According to the second aspect of the present invention, when the object to be measured is outside the predetermined range, the light projection from the distance measurement light projecting means is stopped or dimmed. If such control is performed, even if the case is specific (for example, when the influence of the light from the distance measuring light projecting unit on the angle measuring image sensor cannot be ignored), accurate measurement of the angle is performed. Can be done.

<Invention of Claim 3>
According to the invention of claim 3, the light projection amount of the light emitted from the distance measuring light projecting means is increased or decreased within a range not exceeding the upper limit value according to the amount of received light, and the object to be measured is outside the predetermined range. In this case, since the light projection from the distance measuring light projecting means is stopped or dimmed, the measurement reliability is further improved. This is because when the object to be measured is at a specific position (outside the predetermined range), it is assumed that the influence of the light from the distance measuring light projecting unit on the angle measuring imaging unit cannot be ignored. In this case, however, the control means stops or dims the light projection. On the other hand, if it is within the predetermined range, a stable output can be obtained from the distance measuring image pickup device by controlling the increase and decrease of the light projection amount.

<Embodiment 1>
A first embodiment of an optical measuring device according to the present invention will be described with reference to FIGS. The configuration of this embodiment is as shown in FIG. 1, and the light emitted from the angle measuring laser light source 11 and the distance measuring laser light source 21 is a mirror 31 and a beam splitter (corresponding to the light guiding means of the present invention) 32. And it reaches | attains on the workpiece | work W (to-be-measured object) through the collimator lens 33 (equivalent to the condensing means of this invention), and reflects there.

  The specularly reflected light passes through a collimator lens 33, a beam splitter 32, and a dichroic mirror 34, for example, from an angle measurement image pickup device 12 (corresponding to the angle measurement image pickup means of the present invention) 12 and the two-dimensional CCD. The distance measuring imaging element (corresponding to the distance measuring imaging means of the present invention) 22 is condensed or irradiated. Then, the inclination θ and the distance d of the workpiece W are calculated by the CPU (corresponding to the calculation / control means of the present invention) 4 based on the light condensing or irradiation position.

Both laser light sources 11 and 21 emit light having different wavelengths. For example, the angle measuring laser light source 11 emits laser light having a wavelength λ1, and the distance measuring laser light source 21 is used. Is assumed to emit laser light of wavelength λ2. Laser drive circuits 13 and 23 are connected to the laser light sources 11 and 21, respectively, and drive currents Ia and Ib are supplied to the laser light sources 11 and 21 based on control signals Sa and Sb from the CPU 4, respectively. .
The angle measuring laser light source 11 and the laser driving circuit 13 constitute an angle measuring light projecting means, and the distance measuring laser light source and the laser driving circuit 13 constitute a distance measuring light projecting means.

Of these two control signals Sa and Sb, the control signal Sb controls (supplies or stops) the driving current Ib for driving the distance measuring laser light source 21, and the control signal Sb has a plurality of levels, For example, five stages from Sb1 to Sb5 are set, and each control signal Sb1 to Sb5 supplies driving currents Ib1 to Ib5 having different current values according to the levels, thereby providing a laser light source for distance measurement. The amount of light emitted from 21 is increased or decreased (this is a configuration corresponding to the adjusting means of the present invention).
The drive current is the smallest at Ib1, the current value gradually increases in the order of Ib2, Ib3, and Ib4, and becomes the maximum at Ib5. Therefore, when the control signal is Sb1, the amount of laser light emitted from the distance measuring laser light source 21 is minimized, and when the control signal is Sb5, it is maximized.

  The control signal Sb is set at the central level Sb3 at the start of measurement, but different control signals (Sb1, Sb2, Sb4 based on commands from the CPU 4 when controlling the amount of light emitted from the laser light source 21 for distance measurement described later. , Sb5) is selected.

Further, since the light emitted from the laser light sources 11 and 21 is repeatedly reflected and attenuated, the reflected light of the light emitted from the distance measuring laser light source 21 may enter the angle measuring image sensor. The upper limit value of the light projection amount (the light projection amount when the control signal Sb5 is selected) affects the angle measurement even if the reflected light from the distance measurement laser light source 21 enters the angle measurement image sensor 12. It is set to a value that does not exist. The CPU 4 is provided with a memory so that it is possible to store which stage the current control signal Sb is in.
Incidentally, the control signal Sb5 is provided in this manner to determine the upper limit value of the light projection amount of light emitted from the distance measuring laser light source 21, and this corresponds to the upper limit value setting means of the present invention.

The laser light from the angle measuring laser light source 11 is directly incident on the beam splitter 32, whereas the laser light from the distance measuring laser light source 21 is reflected by the mirror 31 and reflected by the beam splitter. Head to 32.
The laser light from the angle measuring laser light source 11 is incident perpendicularly to the incident surface of the beam splitter 32, and the laser light from the distance measuring laser light source 21 is incident obliquely with respect to the incident surface of the beam splitter 32. It is arranged to let you. As a result, the light axis of the angle measuring laser light source 11 is made parallel to the optical axis (base line axis) LC (L′ C ′) of the optical system, and the light axis of the distance measuring laser light source 21 is the light of the optical system. The state is inclined with respect to the axis LC (L′ C ′).

  The laser light reflected from the beam splitter 32 is converted into parallel light by the collimator lens 33 and irradiated onto the workpiece W. At this time, the laser light from the angle measurement laser light source 11 is irradiated perpendicularly to the surface of the workpiece W when the workpiece W is in a posture without inclination, whereas the laser beam for distance measurement is used. Since the laser light from the laser light source 21 is inclined with respect to the optical axis LC (L′ C ′) of the optical system, the light is irradiated obliquely onto the surface of the workpiece W. The spot diameter of the laser light applied to the workpiece W is smaller for the laser light 21 of the laser light source 21 than for the laser light of the laser light source 11, and the laser light of the laser light source 21 is a laser light source. 11 is irradiated within the irradiation range of the laser beam.

  The specularly reflected light from the workpiece W is collected by the collimator lens 33 and enters the dichroic mirror 34. The dichroic mirror 34 is configured to transmit light having the wavelength λ1 and reflect light having the wavelength λ2, so that the regular reflection light from the angle measuring laser light source 11 is the imaging surface of the angle measuring image pickup device 12. A focused spot is formed by imaging. Further, the specularly reflected light from the distance measuring laser light source 21 is reflected by the dichroic mirror 34 and applied to the imaging surface of the distance measuring imaging element 22. Since the image pickup surface of the distance measuring image pickup element 22 is arranged behind the focal position F of the regular reflection light, a light image having a predetermined size is formed on the image pickup surface. Here, the reason why the imaging surface of the distance measuring image pickup element 22 is not coincident with the focal position F is that the optical path to the focal position F changes according to the distance of the workpiece W. This is because the distance of the workpiece W can be calculated.

  The CPU 4 transmits the control signals Sa and Sb to the laser drive circuits 13 and 23 described above, and takes in and outputs an output signal (imaging signal) Sc from the angle measurement imaging device 12 in synchronization with the transmission of the control signal Sa. In synchronization with the transmission of the signal Sb, an output signal (imaging signal) Sd from the distance measurement imaging element 22 is captured.

  The angle measuring image pickup device 12 and the distance measuring image pickup device 22 are each provided with a shutter (not shown). These two shutters are opened and closed at the same time based on a control signal from the CPU 4. The output signal data Sc and Sd of the reflected light irradiated from the laser light sources 11 and 21 at the same time and reflected by the work W are respectively obtained from the angle measuring image sensor 12 and the distance measuring image sensor 22.

  The configuration of the present embodiment is as described above, and the operation will be described next.

“Calculation of light receiving spot and center position of optical image”
The center position of the condensing spot and the center position of the optical image are calculated based on the output signal Sc from the angle measurement image sensor 12 and the output signal Sd from the distance measurement image sensor 22. More specifically, output signals from the image pickup devices 12 and 22 have large and small variations in output level. Therefore, only the pixel of the output signal whose magnitude is equal to or higher than a predetermined output reference level is extracted as a sample pixel, and the area centroid position is calculated from the extracted sample pixel.

<Area of center of gravity>
Area centroid position = {Σ (MI) / ΣM}
I: Position vector M of each pixel in the irradiation area on the imaging surface of the imaging means M: 1 among the pixels, 0 for the other pixels

"Calculation of slope θ"
The inclination is calculated using a well-known autocollimation method. That is, the inclination direction and the inclination angle are calculated based on the positional relationship between the center position of the condensing spot calculated from the output signal Sc and the reference position on the imaging surface (for example, the center position of the imaging surface).

“Calculation of distance d”
In the distance calculation, the center position of the optical image is corrected based on the calculated inclination θ of the workpiece W, and thereafter, based on the positional relationship between the central position of the optical image and a reference position (for example, the central position of the imaging surface). A distance d from the reference position of the workpiece W is calculated.

  More specifically, for example, when the workpiece W is at the position (1) (distance d1, inclination angle 0) in FIG. 1 (see FIG. 2 for details), the imaging surface of the angle measuring image sensor 12 is shown. Since the position S1 of the condensing spot formed at the position coincides with the reference position Ra, the inclination angle is measured as 0 °. Further, since the optical image L1 on the imaging surface of the distance measuring image sensor 22 is d1 'away from the reference position Rb, the distance d1 is measured based on this.

  When the workpiece W is at the position (2) (distance d2, inclination angle 0) in FIG. 1 (see FIG. 3 for details), the condensing spot formed on the imaging surface of the angle measuring image sensor 12 is shown. Since the position S2 coincides with the reference position Ra, the inclination angle is measured as 0 °. In addition, since the optical image L2 on the imaging surface of the imaging device 22 for distance measurement is separated from the reference position Rb by d2 ', this is measured as the distance d2.

  When the workpiece W is at the position (3) in FIG. 1 (distance d2, tilt angle θ1) (refer to FIG. 4 for details), the position of the light receiving spot formed on the imaging surface of the angle measurement imaging device 12 Since S3 is separated from the reference position Ra by the distance d, the inclination angle θ1 is measured based on this distance. Further, the optical image L3 on the imaging surface of the distance measuring imaging element 22 is separated from the reference position Rb by d3 '. Here, since the workpiece W is inclined at the position (3), the optical image L3 formed on the imaging surface of the imaging device 22 for distance measurement is formed at a position different from the optical image L2 at the position (2). Is done. Therefore, since the CPU 4 calculates the distance by performing correction based on the inclination angle θ1, the distance is eventually measured as d2.

  By the way, as described above, the condensing spot and the center position of the optical image are determined based on the sample pixels having an output value equal to or higher than a predetermined output reference level. If the accuracy increases and the number of pixels is small, an error occurs in the measurement. In particular, in the image sensor 22 for distance measurement, the level of the output signal Sd is likely to decrease because the imaging surface is disposed behind the focal position F of the regular reflection light.

Therefore, in the present embodiment, distance measurement is performed according to the maximum value of the light reception amount of the distance measurement image sensor 22 so that the required number of sample pixels (hereinafter referred to as the reference pixel number) is obtained from the distance measurement image sensor 22. The amount of light emitted from the laser light source 21 is automatically adjusted.
Note that this light projection amount control increases or decreases the light projection amount of light emitted from the distance measurement light projecting unit according to the light reception amount obtained from the distance measurement image capturing unit of the present invention, so that the received light amount becomes a predetermined reference light reception. This is equivalent to the control to reach the level.

  More specifically, as shown in FIG. 5, in STEP 1, the CPU 4 detects the maximum amount of light received by the distance measuring image sensor 22 (maximum value X of the output signal Sd). At this time, the level of the control signal Sb is stored in the memory.

  Next, in STEP 2, it is determined whether or not the magnitude of the maximum value X of the output signal Sd is the same as a predetermined reference light reception level S. Note that the reference light reception level S is expected to obtain the reference pixel number from the image sensor 22 for distance measurement if the maximum value X of the output signal Sd reaches S. is there. In other words, when the maximum value X of the output signal Sd is less than the reference light reception level S, the entire light reception level of each pixel is lowered, so the number of sample pixels extracted from the distance measuring image sensor 22 is the reference pixel. Less than the number. On the other hand, when the reference light reception level S or higher, the number of sample pixels to be extracted is larger than the reference pixel number.

  As a result of the determination in STEP2, when the magnitude of the maximum value X of the output signal Sd is equal to the reference light reception level S (when determined as Yes), the process proceeds to STEP3.

  In STEP 3, the center position of the focused spot is calculated from the output signal Sc from the angle measurement image sensor 12 according to the procedure described above, and the center of the optical image is based on the output signal Sd from the distance measurement image sensor 22. Is determined. And if the condensing spot and the center position of an optical image are calculated, it will shift to STEP4 this time. In STEP 4, the angle θ and the distance d of the workpiece W are calculated according to the procedure described above.

  Thereafter, the process proceeds to STEP 5 and the calculated angle θ and distance d of the workpiece W are output to a monitor or the like.

  On the other hand, when it is determined NO in STEP2, the process proceeds to STEP21. Here, the magnitude of the maximum value X of the output signal Sd is compared with the magnitude of the reference light reception level S. When the maximum value X is larger than the reference light reception level S (when the determination is YES), the process proceeds to STEP22.

  In STEP 22, the CPU 4 lowers the level of the control signal Sb by one step (for example, changed from Sb3 to Sb2). As a result, the value of the drive current Ib is reduced, and the light projection amount of light emitted from the distance measuring laser light source 21 is reduced. Thereafter, the process proceeds to STEP1.

  Next, when the determination in STEP 21 is No (when the maximum value X is smaller than the reference light reception level S), the process proceeds to STEP 31. Here, it is determined whether or not the level of the current control signal Sb is the maximum. If the current control signal Sb is Sb5 (in the case of determination Yes), the distance measurement laser light source 21 emits light. Without increasing or decreasing the amount of light, the process proceeds to STEP 3 to determine the focused spot and the center position of the optical image.

  Moreover, when it determines with No in STEP31, it transfers to STEP32. In STEP 32, the CPU 4 increases the level of the control signal Sb by one step (for example, changed from Sb3 to Sb4). As a result, the value of the drive current Ib increases, and the light projection amount of the distance measuring laser light source 21 increases. Thereafter, the process proceeds to STEP1.

  Thus, the CPU 4 is expected that the magnitude of the maximum value X of the output signal Sd of the distance measurement image sensor 22 is less than the reference light reception level S, that is, the overall light reception level of the distance measurement image sensor 22 is low. In this case, control is performed to increase the amount of light emitted from the laser light source 21 for distance measurement (control of STEP 32). This increase control of the amount of emitted light is repeated until the magnitude of the maximum value X of the output signal Sd of the distance measuring image pickup element 22 reaches the reference light receiving level S, except for some exceptions (described below). When the increase control of the amount of light is completed, sample pixels of the reference number of pixels are obtained from the distance measuring image pickup element 22, and the measurement reliability is improved.

  Further, when the light projection amount of the distance measuring laser light source 21 is increased as described above, there is a concern about the influence on the angle measuring image pickup device 12. This is because the light emitted from the distance measuring laser light source 21 is repeatedly reflected and attenuated, but some of the light enters the angle measuring image sensor 12. If the light projection amount of the distance measuring laser light source 21 becomes too large, the influence on the angle measuring image sensor 12 cannot be ignored. However, in the present embodiment, an upper limit is set for the amount of light emitted from the distance measuring laser light source 21 (corresponding to the control signal Sb5 and the drive current Ib5), and the magnitude of the upper limit is the distance measuring laser. The light emitted from the light source 21 is set within a range that does not affect the angle measurement imaging device 12. Therefore, the reliability regarding the measurement of an angle is also excellent.

  On the other hand, when the magnitude of the maximum value X of the output signal Sd of the distance measuring image sensor 22 is larger than the reference light receiving level S, the CPU 4 reduces the light projection amount of light emitted from the distance measuring laser light source 21. (Step 22 control). As a result, the level of the output signal Sd obtained from the image sensor 22 for distance measurement can be made constant, and power consumption can be saved.

  In the present embodiment, the laser light from the laser light source 21 is irradiated within the laser light irradiation range of the laser light source 11. Thereby, since the irradiation position (measurement position) of both laser beams on the workpiece W overlaps, the accuracy of measurement increases. In order to make the irradiation position (measurement position) of the laser light on the workpiece W constant in this way, for example, the laser light of the laser light source 11 is made smaller than the laser light of the laser light source 21, and the laser light source 11 laser light is irradiated within the laser light irradiation range of the laser light source 21, or the laser light irradiation range of the laser light source 11 and the laser light irradiation range of the laser light source 21 are in part. The structure which overlaps may be sufficient.

<Embodiment 2>
In the second embodiment, as shown in FIG. 6, when the workpiece W is outside the predetermined range R, the CPU 4 controls the light projection amount of light emitted from the distance measuring laser light source 21 to be reduced. . By performing such control, the angle of the workpiece W can be accurately measured regardless of the position of the workpiece W in the vertical direction shown in FIG. Hereinafter, a specific control procedure will be described with reference to FIG.

  First, in STEP 100, laser light is emitted from the angle measuring laser light source 11 and the distance measuring laser light source 21, respectively. At this time, Sb3 is selected as a control signal for driving the distance measuring laser light source 21.

  In STEP 110, the center position of the focused spot is calculated from the output signal Sc from the angle measurement image sensor 12, and the center of the optical image is determined based on the output signal Sd from the distance measurement image sensor 22. The processing in STEP 110 is the same processing as STEP 3 in the first embodiment.

  And if the condensing spot and the center position of an optical image are calculated, it will shift to STEP120 this time. In STEP 120, the angle θ and the distance d of the workpiece W are calculated, and the process proceeds to STEP 130. The processing in STEP 120 is the same processing as STEP 4 in the first embodiment.

  In STEP 130, it is determined whether or not the workpiece W is within the predetermined range R. Here, the predetermined range R has a problem with the distance from the reference position shown in FIG. 6 to the workpiece W. If the workpiece W is within this range, the reflected light of the light emitted from the distance measuring laser light source 21 is reflected. This is a range that does not affect the measurement of the angle even if it enters the image sensor 12 for angle measurement. In order to determine whether or not the workpiece W is within the predetermined range R, the distance dx may be compared with the magnitude of R, and the distance dx can be calculated by d-ds.

  When the distance dx is equal to or less than R, the process proceeds to STEP140. In STEP 140, it is determined whether or not the control signal Sb is Sb3. When the control signal Sb is Sb3 (when the determination is YES), the process proceeds to STEP 150, and the angle and distance data of the workpiece W is output. When the control signal Sb is other than Sb3 (Sb1 or Sb2), the process proceeds to STEP141.

  In STEP 141, the control signal Sb is set to Sb3, and then the process proceeds to STEP 150 where data is output.

  If it is determined No in STEP 130 (when the workpiece W is outside the predetermined range R), the process proceeds to STEP 131. Here, it is determined whether or not the control signal Sb is Sb1. If the determination is Yes, the process proceeds to STEP 150 and data is output.

  On the other hand, when the determination in STEP 131 is No (when the control signal Sb is other than Sb1), the process proceeds to STEP 132. Here, the CPU 4 lowers the level of the control signal Sb by one step (for example, changed from Sb3 to Sb2). As a result, the value of the drive current Ib is reduced, and the amount of light emitted from the distance measuring laser light source 21 is reduced. Thereafter, the process proceeds to STEP 150 and data is output.

  From the above, the workpiece W is outside the predetermined range R, and the influence of the reflected light of the light emitted from the distance measuring laser light source 21 on the angle measuring image sensor 12 cannot be ignored. In this case, the CPU 4 performs control to reduce the light projection amount of light emitted from the distance measuring laser light source 21 (control of STEP 132). Therefore, an accurate measurement result can be obtained for the angle of the workpiece W regardless of the position of the workpiece W.

  In addition, when the workpiece W that has been outside the predetermined range R returns to the area within the predetermined range R, the distance measurement laser light source 21 that has been dimmed by the CPU 4 returning the control signal Sb to Sb3. Is returned to the initial light emission amount (control of STEP 141). Therefore, after returning, a highly reliable measurement result can be obtained for both the angle and distance of the workpiece W. Note that the configuration of the optical device according to the second embodiment is the same as that of the first embodiment, and a description thereof will be omitted.

<Embodiment 3>
Next, Embodiment 3 of the present invention will be described with reference to FIG. In the third embodiment, the projection light amount control of the distance measuring laser light source 21 by the CPU 4 in the first embodiment and the projection light amount control in the second embodiment are combined. Since STEP 1 to STEP 32 are the same as those described in the first embodiment, the subsequent control will be described.

  In STEP 130, it is determined whether or not the workpiece W is within the predetermined range R. If the workpiece W is within the predetermined range R (if the determination result is YES), the process proceeds to step 150.

  On the other hand, when it determines with No, it transfers to STEP135. Here, the supply of the drive current Ib is stopped when the CPU 4 issues a command to stop the transmission of the control signal Sb. Thereby, the light projection from the distance measuring laser light source 21 is stopped. Thereafter, the process proceeds to STEP 150 and data is output.

  If such light emission amount control is performed, the CPU 4 automatically increases or decreases the light emission amount according to the maximum value X of the output signal Sd from the distance measuring image pickup device 22 (control from STEP2 to STEP32). As a result, the output signal Sd is stabilized and the reliability of the measurement accuracy is improved. Further, when the workpiece W is outside the predetermined range R, the CPU 4 stops the light projection from the distance measuring laser light source 21 (control of STEPs 130 and 135). Even in this case, the angle of the workpiece W is accurate. A measurement result is obtained.

<Embodiment 4>
Next, a fourth embodiment of the present invention will be described with reference to FIG. The difference between the present embodiment and the first embodiment is that a collimator lens 14 (first collimator lens) is disposed between the angle measuring laser light source 11 and the beam splitter 32, and the distance measuring laser light source 21 is A collimator lens 24 (second collimator lens) is arranged between the mirror 31 and the beam from each laser light source 11, 21 is changed to parallel light and then reaches the beam splitter 32. Yes. A converging lens 36 is disposed between the dichroic mirror 34 and the beam splitter 32.

  With this configuration, the laser light from both laser light sources 11 and 21 is converted into parallel light by the respective collimator lenses 14 and 24 and then guided to the beam splitter 32. It is not necessary to adjust the optical distance to the beam splitter 32, and the assembly accuracy of the optical system in the apparatus can be moderated, and the adjustment work of the optical system can be simplified. Note that, regarding the control of the light projection amount in this embodiment, the light projection amount control in any one of the first to third embodiments is performed.

<Embodiment 5>
Next, Embodiment 5 of the present invention will be described with reference to FIG. The difference between the present embodiment and the fourth embodiment is that a polarizing beam splitter 37 that reflects S-polarized light and transmits P-polarized light is disposed in place of the beam splitter 32, and further between the polarizing beam splitter 37 and the workpiece W. Are provided with a quarter-wave plate 38. The surface of the workpiece W is preferably a mirror surface.

  In general, the laser light is linearly polarized. Therefore, when the laser beams from both laser light sources 11 and 21 are irradiated onto the polarization beam splitter 37, the S-polarized light is reflected and travels toward the quarter-wave plate 37, and the P-polarized light is To Penetrate. The S-polarized light is changed to circularly-polarized light by passing through the quarter-wave plate 38 and is irradiated onto the workpiece W. The regular reflection light from the work W is transmitted through the quarter-wave plate 38 as circularly polarized light. At this time, the circularly polarized light is changed to P-polarized light, and the light is transmitted through the polarization beam splitter 37 and irradiated to the respective image sensor means 12 and 22.

By adopting the configuration of this embodiment, it is possible to reduce optical loss and improve the S / N ratio in mirror body detection. In addition, since the light emitted from the laser light sources 11 and 21 is linearly polarized light, the configuration for emitting linearly polarized light can be greatly simplified.
Note that, regarding the control of the light projection amount in this embodiment, the light projection amount control in any one of the first to third embodiments is performed.

<Embodiment 6>
Next, a sixth embodiment of the present invention will be described with reference to FIG. In the first embodiment, the light emitted from the angle measuring laser light source 11 is reflected by the beam splitter 32 and guided to the workpiece W. In the sixth embodiment, the light emitted from the angle measuring laser light source 11 is used. Is converted into parallel light through the collimator lens 14 and directly incident on the workpiece W. The distance measurement imaging element 22 is disposed in front of the distance measurement reflected light reflected by the workpiece W, and the distance measurement reflected light passes through the collimator lens 14 and then the distance measurement imaging element. It is designed to receive light directly.

Thus, since the attenuation of light can be suppressed to a minimum by reducing the number of reflections between the distance measurement laser light source 21 and the distance measurement image sensor 22, it is compared with the case where reflection is repeated several times. Thus, an output signal having a large output value is obtained from the distance measuring image pickup element 22.
Note that, regarding the control of the light projection amount in this embodiment, the light projection amount control in any one of the first to third embodiments is performed.

<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) In the first embodiment, the adjustment of the light projection amount of the distance measuring laser light source 21 is made in five stages, but any adjustment is possible as long as the upper limit value is not exceeded.

  (2) In the first embodiment, the magnitude of the amount of light received by the distance measurement imaging unit 22 is determined based on the maximum value X of the output signal Sd. For example, the determination is based on the average value or peak value of the output signal Sd. You may do.

  (3) In the first embodiment, the light receiving spot and the center position of the light image are calculated from the output signals Sc and Sd of the distance measuring image sensor 22 and the angle measuring image sensor 12, but the center position of the area is calculated. For example, the center position may be specified based on the volume centroid position.

  (4) In the second embodiment, the range related to the distance d of the workpiece W is used as the predetermined range, but it may be a range related to the angle θ of the workpiece W. In this case, when the workpiece W is tilted by a predetermined range θr or more, the light from the distance measuring laser light source 21 is dimmed or stopped so that the light from the distance measuring laser light source 21 is converted into an angle measuring image sensor. 12 does not enter the light, or the effect is small even if it enters.

  (5) In the third embodiment, when the workpiece W is outside the predetermined range R, the light projection from the laser light source 21 for distance measurement is stopped based on the control signal from the CPU 4. May be provided to stop the flooding manually.

The schematic diagram which showed the whole structure of the optical measuring device which concerns on Embodiment 1. FIG. Schematic showing work position and reflected light path Schematic showing work position and reflected light path Schematic showing work position and reflected light path Light emission amount control flowchart The schematic diagram which showed the whole structure of the optical measuring device which concerns on Embodiment 2. FIG. Light emission amount control flowchart Flowchart of light intensity control according to the third embodiment The schematic diagram which showed the whole structure of the optical measuring device which concerns on Embodiment 4. FIG. Schematic diagram showing the overall configuration of the optical measurement device according to the fifth embodiment The schematic diagram which showed the whole structure of the optical measuring device which concerns on Embodiment 6. FIG.

Explanation of symbols

4 ... CPU
DESCRIPTION OF SYMBOLS 11 ... Laser light source for angle measurement 12 ... Image sensor for angle measurement 13 ... Laser drive circuit 21 ... Laser light source for distance measurement 22 ... Image sensor for distance measurement 23 ... Laser drive circuit W ... Workpiece

Claims (3)

An optical measuring device that irradiates light to an object to be measured and measures the inclination and distance of the object to be measured based on the reflected light,
A light guiding means for guiding light from the angle measuring light projecting means to the object to be measured;
Imaging means for angle measurement;
Condensing means for condensing the reflected light for angle measurement reflected by the object to be measured and guiding it to the imaging surface provided in the imaging means for angle measurement;
A distance measuring light projecting means capable of irradiating light from a direction inclined by a predetermined angle with respect to the object to be measured;
An adjustment means capable of adjusting the light projection amount of the light emitted from the distance measurement light projecting means; and
Distance measurement capable of imaging the distance measurement reflected light emitted from the distance measurement light projecting means and reflected by the object to be measured at the same timing as the angle measurement imaging means images the angle measurement reflected light. Imaging means for use;
Calculation means for calculating the distance and angle of the object to be measured based on the angle measurement reflected light and the distance measurement reflected light respectively obtained from the angle measurement imaging means and the distance measurement imaging means. When,
Prior to the calculation of the distance and angle by the calculation means, the received light amount is predetermined by increasing or decreasing the light projection amount of the light emitted from the distance measurement light projection means according to the light reception amount obtained from the distance measurement imaging means. Control means for controlling the adjusting means so that a reference light receiving level of
An optical measurement apparatus comprising: an upper limit value setting unit for determining an upper limit value of the light projection amount with respect to the adjustment of increase / decrease of the light projection amount of the light emitted from the distance measurement light projection unit by the adjustment unit. An optical measuring device that irradiates light to an object to be measured and measures the inclination and distance of the object to be measured based on the reflected light,
A light guiding means for guiding light from the angle measuring light projecting means to the object to be measured;
Imaging means for angle measurement;
Condensing means for condensing the reflected light for angle measurement reflected by the object to be measured and guiding it to the imaging surface provided in the imaging means for angle measurement;
A distance measuring light projecting means capable of irradiating light from a direction inclined by a predetermined angle with respect to the measurement object;
An adjustment means capable of adjusting the light projection amount of the light emitted from the distance measurement light projecting means; and
Distance measurement capable of imaging the distance measurement reflected light emitted from the distance measurement light projecting means and reflected by the object to be measured at the same timing as the angle measurement imaging means images the angle measurement reflected light. Imaging means for use;
Calculation means for calculating the distance and angle of the object to be measured based on the angle measurement reflected light and the distance measurement reflected light respectively obtained from the angle measurement imaging means and the distance measurement imaging means. When,
It is determined whether or not the distance calculated by the calculating means is within a predetermined range, and when the object to be measured is outside the predetermined range, the light projection from the distance measuring light projecting means is stopped, Alternatively, an optical measuring apparatus comprising control means for controlling the adjusting means so as to reduce light. The control means includes
2. The optical system according to claim 1, wherein when the object to be measured is out of a predetermined range, the light projection from the distance measuring light projecting unit in claim 2 is controlled to be stopped or dimmed. 3. measuring device.

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