JPH0451766B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an automatic sighting device, in particular, a land station equipped with a light wave distance meter to measure the position of a coastal work platform,
It is suitable for use in marine work systems that perform highly accurate positioning.

[Summary of the invention]

Automatic vision that detects the amount and direction of deviation of the collimation optical axis and corrects the deviation even in the amount of return light of the almost parallel two-axis collimation servo light sent to the reflector at the target point. It is a semi-equipment.

[Conventional technology]

BACKGROUND ART In civil engineering work, port construction work, coastal construction work, etc., there is a need for a system that measures the position or distance of a movable object such as a bulltozer, dredger, or work platform from a fixed position.

Conventionally, a light wave distance meter is used on one side of a fixed position and a moving object, and a reflector (corner cube prism, etc.) on the other side.
There is a known system in which the optical axes are automatically collimated so that the position can be measured without any trouble even if a moving object such as a ship's platform swings (for example, -8221 Publication).

A known automatic collimation type optical distance meter has a collimation servo optical axis parallel to the distance system, and divides the collimation servo light from the measurement target point into four light receiving elements (the light receiving surface is divided into four horizontal and vertical quadrants). A servo that detects deviations in the angle of incidence in the vertical and horizontal directions (e.g., a photodiode divided into It has a system.

[Problem that the invention seeks to solve]

The automatic collimation device installed in conventional automatic collimation type optical distance meters receives the collimation servo light emitted from the reflector side and aligns the optical axis of the objective lens with the servo optical axis of the other station. Because of this configuration, it was necessary to provide a collimation servo light source in the partner station.

Therefore, it is conceivable to transmit collimated servo light from the local station, receive the servo light reflected by a reflector, and then collimate the optical axis of the objective lens to the reflector. In this case, it is necessary to use a corner cube prism as a reflector to ensure that the transmitted servo light is returned to the own station. However, when a corner cube prism is used as a reflector, even if the collimated optical axis is slightly shifted, the emitted light returns in parallel, so the returned light does not contain information regarding the angular shift of the optical axis. Therefore, since the four-part photodiode cannot detect the deviation of the optical axis, it is not possible to configure a servo system for automatic collimation.

SUMMARY OF THE INVENTION An object of the present invention is to enable automatic collimation by detecting a shift in the optical axis using servo light reflected by a reflector and returned.

[Means for solving problems]

The automatic collimating optical distance meter of the present invention includes means (light emitting elements 20a, 20c) for transmitting substantially parallel biaxial collimating servo lights 25a and 25c to a target point, and a means for transmitting collimated servo lights 25a and 25c to a target point, and A means for receiving the collimating servo light (light receiving element 19), a means for detecting the deviation of the optical axis 21 to be collimated based on two light reception levels corresponding to each collimating servo light (servo circuit 2a), The apparatus includes a mechanism (X-axis and Y-axis gear motors 11, 12) that corrects the optical axis angle based on the output of the detection means.

The collimating servo lights of the two axes have different carrier frequencies or wavelengths, and the means for receiving the collimating servo lights discriminates between the carrier frequencies or the collimating servo lights and separates and derives received light signals corresponding to the two lights. A discriminating means (filter amplifiers 27a to 27d) is provided.

[Effect]

Since the direction of the optical axis deviation to be corrected can be determined from the relative reception level of the return light of each biaxial collimated servo light, the optical axis is deflected in the direction in which the deviation is corrected. Furthermore, the received light level distribution with respect to the deviation of the optical axis exhibits a bimodal characteristic corresponding to the interval between the two axes. Since the midpoint between the two peaks becomes the collimation point, the collimation point is detected by detecting the cross point of the bimodal characteristics, a predetermined level range of the valley, an overlapping portion, etc.

〔Example〕

FIG. 1 is an overall block diagram of an automatic collimation measurement system for a marine work platform showing one embodiment of the present invention, and FIGS. 2 and 3 are front views of a light wave distance system and a reflector. The light wave distance meter 3 on the land side is arranged in a collimation device 2 provided on the base 1. A reflector 4 including a corner cube prism 7 is arranged on the ship's platform side.

The collimation device 2 includes a horizontal arm 8 that is rotatable in a horizontal plane and a vertical arm 9 that is rotatable in a vertical plane,
X-axis gear motor 11 and Y-axis gear motor 12, respectively
driven by. A light transmitting/receiving unit 15 comprising light transmitting lenses 13a to 13d and a light receiving lens 14 is mounted on the vertical arm 9.

The light transmitting lenses 13a to 13d are provided around the light receiving lens 14 on the upper, lower, left and right sides, respectively, as shown in FIG. and deflection cylindrical lenses 17a to 17d. Each convex lens 16a-1
At the focal point of 6d are light emitting elements 20a to 20 such as LEDs.
d is arranged, and a light receiving element 19 such as a photodiode is arranged at the focal point of the light receiving lens 14.

During measurement, a collimating telescope 41 provided at the measuring station is used to locate the target 4 provided at the reflecting station.
2, adjust the vertical fine adjustment knob 43 and the horizontal fine adjustment knob 44 to adjust the objective lenses 13a to 13d,
14 is collimated onto the corner cube prism 7.

When a power switch (not shown) is turned on after collimating the optical axis of the light-receiving lens 14 to the corner cube prism 7, the collimation device 2 and the optical distance meter 3 are put into operation. As a result, the collimation servo circuit 2a operates, and the oscillation outputs of the oscillators 24a to 24d are transmitted to each light emitting element 20 via the drive circuits 23a to 23d.
a to 20d. Oscillators 24a-24d
The oscillation frequency is, for example, 2.5KHz, 4KHz, 5.5KHz,
It has been changed to 7KHz. As a result, the collimated servo light 25a is amplitude-modulated at different frequencies.
25d is projected toward the reflector 4 arranged on the ship's platform side through the light transmitting lenses 13a to 13d.

The cylindrical lenses 17a and 17c arranged in front of the vertical pair of convex lenses 16a and 16c are
The collimated servo lights 25a and 25c are focused only in the vertical direction. Also, a horizontal pair of convex lenses 16b and 16
Cylindrical lens 17 placed in front of d
b, 17d converge the collimated servo lights 25b, 25d only in the horizontal direction. Therefore, these collimating servo lights 25a to 25d become substantially parallel flat lights and enter the corner cube prism 7 of the reflector 4. Each of the collimated servo lights 25a to 25d is a substantially parallel light beam, but it diverges somewhat depending on the area of the light emitting elements 20a to 20d, and the amount of light is large at the center and attenuates toward the periphery.

When the optical axes of the objective lenses 13a to 13d and 14 are collimating the corner cube prism 7 as shown in FIG. It is formed large enough to allow a large amount of light to enter. Therefore, when the optical axis is not deviated, the large light intensity portion of the collimating servo lights 25a to 25d is returned to the measurement station side by the corner cube prism 7.
The light enters the light-receiving lens 14 as a light beam as shown in FIG. 6, respectively.

Each collimated servo light 25 entering the light receiving lens 14
a to 25d are light receiving lenses 1 as shown in FIG.
The light is received by the light receiving element 19 placed at the focal point of No. 4. Each collimating servo light 25a to 25d is connected to the light receiving element 1.
9 performs photoelectric conversion, and the light receiving element 19 outputs a received light output proportional to the amount of received light.

This light reception output is amplified by a preamplifier 26 and then given to a discrimination means 29, where the light reception output corresponding to each of the collimated servo lights 25a to 25d is discriminated. In the example shown in FIG. 1, each collimating servo light 25a~
Since the signal 25d is amplitude modulated, the discrimination means 29 is composed of the filter amplifiers 27a to 27d and the detectors 28a to 28d. That is, the output of the preamplifier 26 is given to filter amplifiers 27a to 27d, where it is amplified for each received light output corresponding to the collimated servo lights 25a to 25d. The outputs of the filter amplifiers 27a to 27d are sent to the detectors 28a to 28.
d, is detected, and converted into a DC level signal with a level value corresponding to the received light output. these
After the DC level signal is converted into a digital value by the A/D converter 30, the system controller (microcomputer) uses it as a signal to detect the difference in received light intensity between the upper and lower (U, D) and left and right (L, D) sides.
Given to 31.

In the system controller 31, the deviation of the optical axis is calculated based on the received light intensity in the upper, lower, left, and right directions. This calculation is performed in the X-axis direction and the Y-axis direction, and drive pulses are derived to the motor drive circuits 32X and 32Y for each axis based on the calculation results. This drives the X-axis and Y-axis gear motors 11 and 12, respectively, and adjusts the optical axis. The servo loop from the light receiving element 19 to the motors 11 and 12 operates, for example, to make the received light intensity of the light receiving element 19 equal in each of the upper and lower pairs (U, D) and the left and right pairs (L, R).

FIG. 7 shows the light reception levels of the collimating servo lights 25a and 25c. When the optical axis 21 of the objective lens is not shifted, for example, the vertical pair of collimating servo lights 25a and 25c
5a and 25c have the same light reception level, and no level difference occurs. In FIG. 5, it is assumed that the corner cube prism 7 moves upward and the optical axis 21 shifts downward. In this case, the light amount of the lower collimating servo light 25c entering the corner cube prism 7 decreases, and the light amount of the upper collimating servo light 25a increases. Therefore, as shown in FIG. 7, the light receiving level of the lower collimating servo light 25c decreases, so that the light receiving level _E1 of the upper collimating servo light 25a and the light receiving level E1 of the lower collimating servo light 25c decrease. ₂ , a level difference Δe occurs, and a deviation angle Δθ is detected. Y-axis gear motor 1 is adjusted so as to eliminate this level difference Δe.
2 is driven to correct the deviation of the optical axis 21.

If the optical axis 21 is shifted upward or to either the left or right side in the X-axis direction, a similar operation is performed to correct it.

The deviation of the optical axis detected by the light receiving element 19 is displayed on the display 3 connected to the system controller 31.
3A to 33C. Indicators 33A, 33
Each pointer B indicates the deviation from the origin of the X axis (horizontal direction) and Y axis (vertical direction), and the pointer of the display 33C indicates the overall light reception level (light reception intensity) of the light receiving element 19.
shows. Note that this light reception level may be displayed as a bar graph using an LED.

When the servo is active, the optical axis of the collimation device 2 provided at the land station is correctly directed toward the reflector 4 of the platform station, allowing for side range.

When the circuit section 34 of the light wave distance meter 3 is activated in the collimated state, the light transmitting/receiving unit 36 placed at the focal position of the objective lens emits a distance measuring light 3 of about 15 KHz (FM).
7 transmission and reception of reflected light from the measurement point is performed. The phase difference between the transmitted light and the received light is measured by the circuit section 34, and the inter-office distance is calculated based on it. The calculated distance data is sent to the system controller 31 via the interface 38 and displayed or printed out.

As shown in FIG. 2, rotary encoders 39 and 40 are provided on the X-axis and Y-axis, respectively.
Can be used as a transit (theodolite). For example, assume that the boat platform 22 shown by the solid line in FIG. 8 moves to the position shown by the dotted line after a certain period of time. In this case, since the platform 22 is automatically sighted, the angle θ ₁ after movement can be automatically measured using the position shown by the solid line as the origin, and the measured angle θ ₁
By reading , the angular position after movement can be immediately detected.

This distance measurement system is designed to measure both distance and angle, so if the absolute position before movement is known, it can be calculated by reading both the angle and distance data after movement. Absolute position can be detected.

Further, the rotary encoder 40 provided on the Y-axis can detect the inclination angle θ ₂ with respect to the horizontal plane, as shown in FIG. 9, and convert the inclination distance into a horizontal distance.

When the automatic sighting device 2 and the rotary encoders 39, 40 are combined in this manner, it is possible to automatically track a moving object and automatically measure the angle from the origin, thereby constructing a transit for a moving object. Furthermore, since the distance and angle from the origin can be detected, the trajectory of the moving object can be obtained in real time.

Collimation can also be achieved by swinging the optical axis of the objective lens vertically and horizontally so that the light receiving level of each of the collimating servo lights 25a to 25d is below a predetermined reference level. In this case, a large light amount portion of each of the collimating servo lights 25a to 25d is positioned around the corner cube prism 7. FIG. 10 shows an example in which the optical axes of the light transmitting lenses 13a and 13c are opened by a predetermined angle toward the outside so that the large light intensity portions of the collimated servo lights 25a and 25c hit the periphery of the corner cube prism 7. There is. Note that in this case, the cylindrical lens does not necessarily need to be provided.

By adjusting the optical axes of the respective light transmitting lenses 13a to 13d in this manner, a pair of light receiving outputs as shown in FIG. 11 can be obtained. Therefore, the reference level Vref
is set and the received light outputs 25a and 25c are controlled to be below the reference level Vref, so that the received light outputs can be set to be at the trough of the pair of output levels. can be made compliant.

FIG. 12, FIG. 14, and FIG. 15 are principal circuit diagrams showing a specific example of detecting a collimation position.

When detecting a point where the levels of the pair of received light outputs A and B match, the received light outputs A and B are input to the comparator 55 as shown in FIG. 12A. In this case, the output signal S ₁ obtained from the output side of the comparator 55
As shown in Figure C, when the received light output A>B, a signal _P1 of "1" (high level) is output, and when A<B
At this time, a signal _P2 of "0" (low level) is output.
When A>B, the optical axis 21 of the objective lens is shifted to the right in _FIG . Sent. On the other hand, when the received light output B>A, the optical axis 21 is deviated to the left, so a right movement pulse for moving the optical axis 21 to the right is transmitted to the X-axis gear motor 11 by the control signal _P2 , and the optical axis 21 is shifted to the right. collimates the matching point 56 of the pair of received light output levels A and B. Note that when detecting a coincident point in this manner, either the left or right moving pulse is always output and is dynamically stabilized near both sides of the collimation point.

In addition, as shown in FIG. 13, each collimating servo light 25
When almost all of the light enters the light receiving lens 14 completely in the large light intensity portions a and 25c, the two light receiving outputs both reach a near peak around the deviation angle of 0 degrees, as shown in FIG. 14B. Since the values overlap, it is difficult to detect matching points.

Therefore, as shown in FIG. 14A, the comparator 5
5 as a subtracter, the output S ₁ as shown in C in the same figure
get. The part where this output S ₁ is above a positive predetermined level
At P ₁ , the optical axis is swung to the left, and at P ₂ , where the output S ₁ is below a negative predetermined level, the optical axis is swung to the right. Furthermore, the output S ₁ is given to the window comparator 57 to detect the range ±Δx near the zero output (FIG. 14C). In this range, the output _S2 shown in figure D is obtained. This output signal _S2 indicates A≒B, so if the left and right optical axis movement is prohibited by this output, the sighting range 60 is set within a predetermined minute angle range ±α degrees with the sighting point 0 degrees as the center. can be achieved. Note that the ±α degree section corresponds to the valley of the absolute value of the difference between the pair of outputs A and B.

FIG. 15A shows another example of detecting the collimation range 60. In this case, the light reception outputs A and B are input to comparators 61 and 62, respectively. A reference level voltage Vref is given to each comparator 61, 62, and the output signal _S3 ,
As shown in Figure D, _S4 becomes "1" when the voltage is higher than the reference level voltage Vref, and becomes "0" when it is lower than the reference level voltage Verf. These output signals S ₃ , S ₄
is applied to the AND circuit 63, and when the output signals S ₃ and S ₄ are both "1", the AND circuit 63 outputs the collimation range detection signal S ₅ and the detection of the collimation range 60 is performed. As shown in FIG. F, the left and right movement pulses P ₁ and P ₂ are not transmitted in the collimation range 60, and the movement of the optical axis 21 is stopped.

Collimated servo light 25a, 25 returned by reflector 4
When only a part of the large light amount portion c enters the light receiving lens 14, light receiving outputs A' and B' as shown in FIG. 15C are obtained. In this case, the signals S ₃ and S ₄ output from the comparators 61 and 62 are as shown in FIG. E, so instead of the AND circuit 63,
A NOR circuit is provided to output a collimation range detection signal _S5 when the two output signals _S3 and _S4 are both "0".

Note that although the above description has been made in the horizontal direction, the same applies to the vertical direction.

Collimation servo lights 25a to 25 as shown in Fig. 15C.
In order to obtain bimodal light receiving characteristics by allowing only a part of the light beam d to enter the corner cube prism 7, the light receiving range of the corner cube prism 7 may be made narrower than the interval between the two-axis servo lights. Further, the biaxial divergence angle of each collimated servo light may be increased.

FIG. 16 shows a block diagram of an automatic collimation and distance measuring system in which one light receiving lens 14 is used both as a collimation servo system and as a light wave distance meter.

As shown in FIG. 17, this automatic collimation and distance measuring system is provided with a light transmitting lens 3a for distance measuring light around a light receiving lens 14. The distance measuring light 37 emitted from the distance measuring light emitting element 46 disposed at the focal point of the light transmitting lens 3a is reflected by the corner cube prism 7 of the reflection station and enters the light receiving lens 14.
A beam splitter 48 is inserted into the optical axis of the light receiving lens 14 at an angle of 45°, and the distance measuring light 37 is reflected by the beam splitter 48 and focused on the distance measuring light receiving element 47. This light reception output is sent to the distance system circuit 34 to calculate the distance. Note that distance measuring light 3
By using a dichroic mirror tuned to the wavelength of 7 as the beam splitter 48, an optical system with low loss can be constructed.

In addition, in the ranging system shown in FIG. 16, a joystick 49 is used as a means to finely adjust the direction of the optical axis.
is provided. Move the joy stick 49 in the X direction and Y.
When the operation is performed in the direction, the corresponding voltage output is sent to the system controller 31 via the A/D converter 50, and fine adjustment drive pulses are derived from the controller 31 to the motor drive circuits 32X, 32Y to drive each motor 11, 12. is slightly shaken. Therefore, the operator can sight the target station by operating the joystick 49 while looking through the sighting telescope 41 of the optical distance meter 3, for example.

One corner cube prism 7 can reflect light incident from an approximately 30° range toward its light source. However, a moving object may move continuously over a range of 30 degrees, or may rotate completely in a 360 degree direction. In such a case, if only one corner cube prism 7 is provided, it will be necessary to orient the reflector 4 toward the measuring station. FIG. 18 shows an example in which the support body 5 to which the corner cube prism 7 is attached is formed into a cylindrical shape, and the corner cube prism 7 is provided over the entire circumferential surface of the support body 5. In this case, 12 corner cube prisms 7 may be provided at 30° intervals, but in consideration of the safety factor, it is preferable to provide about 18 corner cube prisms 7 at 20° intervals.

One corner cube prism 7 can reflect the vertical, horizontal, and horizontal collimating servo lights 25a to 25d and the ranging light 37 toward the measurement station. However, when the light is reflected by one corner cube prism 7, the incident light and the reflected light are reversed vertically and horizontally. Therefore, as shown in FIG. 19, small corner cube prisms 7a to 7d are provided at the top, bottom, left and right inside the casing 52, and each of the light transmitting lenses 13a to 13d corresponds to the corner cube prisms 7a to 7d as one unit. A reflector 53 may also be formed. By doing this, each collimated servo light 25a to 25
d can be returned to the light receiving lens 14 independently. In this case, the distance measuring light 37 is reflected by each of the corner cube prisms 7a to 7d, but a corner cube prism exclusively for the distance measuring light 37 may be provided.

FIG. 20 shows how the collimated servo lights 25a and 25c emitted from the light emitting elements 20a and 20c, respectively, are reflected to the light transmitting side. The upper collimating servo light 25a is connected to the upper corner cube prism 7.
The light is reflected by a and enters the upper portion of the light receiving lens 14. Further, the lower collimating servo light 25c is reflected by the lower corner cube prism 7c and enters the lower portion of the light receiving lens 14. Although not shown, the left and right collimating servo lights 25a and 25c are also
The light is reflected by the corner cube prisms 7b and 7d provided on the left and right sides of the reflector and enters the left and right parts of the light receiving lens 14.

If each of the collimated servo lights 25a to 25d can be divided and returned to the light receiving lens 14 in this way, it becomes possible to use the four-divided light receiving element 54 as a light receiving element. If the 4-split light receiving element 54 is used,
Since the light reception output of each of the collimating servo lights 25a to 25d can be extracted independently, there is no need to modulate these collimating servo lights 25a to 25d at different frequencies. Therefore, the oscillators 24a to 24d on the light transmitting side and electrical discrimination means such as electric filters on the light receiving side are not required, and the circuit configuration can be simplified.

In this case, the wavelengths of the collimated servo lights 25a to 25d are changed to, for example, 770 nm, 850 nm, 900 nm, and 1000 nm, and an optical bandpass filter is provided in front of the 4-division light receiving element 54 to perform optical discrimination.

In this embodiment, an example is shown in which four collimated servo lights are emitted as pairs in the vertical and horizontal directions. However, as shown in FIG. 21, the light transmitting lenses 13a and 13c are arranged vertically, and the collimating servo lights transmitted from these light transmitting lenses form a pair of vertical collimating servo lights. The light transmitting lens 13b is arranged in the horizontal direction of the light transmitting lens 13c (or 13a), so that the collimated servo lights transmitted from the light transmitting lenses 13c and 13b form a pair of horizontal collimated servo lights. You can also do this.

FIGS. 23 to 25 show an example in which automatic collimation is performed using a pair of collimating servo lights, that is, two lights. In this case, two light transmitting lenses 13a,
13b is preferably provided at 45 degrees with respect to the horizontal direction (vertical direction) as shown in FIG.

In the example shown in FIG. 23, the collimating servo light 67 projected from the light transmitting lens 13a is amplitude-modulated alternately at frequencies f ₁ and f ₂ , and the collimating servo light 68 projected from the light transmitting lens 13b is is amplitude-modulated alternately at frequencies f ₂ and f ₄ . These modulations are synchronized with collimated servo lights 67 and 68, and the light receiving element 19 receives collimated servo lights with frequencies f ₁ and f ₃ and collimated servo lights with frequencies f ₂ and f ₄ . Light enters alternately. The light receiving output of the light receiving element 19 is applied to filter amplifiers 70a to 70d constituting the discriminating means 29 and discriminated. The light reception outputs of the pair of collimating servo lights of frequencies f ₁ and f ₃ are given to the comparator 71, and the difference voltage therebetween is derived to the motor drive circuit 32X. As a result, the value of the differential voltage becomes approximately zero.
The shaft gear motor 11 is driven to perform horizontal automatic collimation.

In addition, the received light output of the pair of collimating servo lights with frequencies f ₂ and f ₄ is given to the comparator 72, and the difference voltage is led to the motor drive circuit 32Y to drive the Y-axis gear motor, thereby causing the vertical direction. Automatic aiming is performed.

In the example shown in FIG. 24, the collimating servo light 74 projected from the light transmitting lens 13a is amplitude-modulated at a frequency f ₁ , and the collimating servo light 75 projected from the light transmitting lens 13b is modulated at a frequency _f2 . The amplitude is modulated. The light receiving output of the light receiving element 19 is applied to filter amplifiers 70a and 70b, and the light receiving outputs corresponding to the respective collimated servo lights 74 and 75 are discriminated. Each of the discriminated light reception outputs is applied to a comparator 76, and the detected differential voltage is applied to a movable terminal 77c of a switch 77. The switch 77 alternately switches the movable terminal 77c to the fixed terminals 77a and 77b using a switching pulse 78a output from a switching pulse generator 78. As a result, the differential voltage of the comparator 76 is supplied in a time-sharing manner to the motor drive circuits 32X and 32Y connected to the fixed terminals 77a and 77b, respectively.
The optical axis of the objective lens is swung so that there is no difference in detection levels in the horizontal and vertical directions.

Figure 25 shows a four-division light-receiving element 5 similar to Figure 20.
This is an example in which the frequencies of two lights are made the same using 4.
In this case, the light receiving parts 54b and 5 located in the left and right direction
The light reception output of 4d is given to the comparator 80, and the detected error voltage is derived to the motor drive circuit 32X. As a result, the optical axis of the objective lens is swung horizontally so that the light receiving outputs of the light receiving sections 54b and 54d are the same, and horizontal collimation is performed.

Similarly, light receiving sections 54a and 54 located in the vertical direction
The received light output of c is applied to the comparator 81, the detected error voltage is derived to the motor drive circuit 32Y, and collimation in the vertical direction is similarly performed.

〔Effect of the invention〕

As described above, the present invention transmits substantially parallel two-axis collimated servo lights with different carrier frequencies or wavelengths to a target point, and generates two collimated servo lights corresponding to each collimated servo light reflected by a reflector at the target point. Since two received light signals are obtained by frequency or wavelength discrimination, and the deviation of the optical axis to be collimated is detected based on the level of the discriminated received light output, automatic collimation is performed, so a servo light source is installed on the reflector side. There is no need to set the automatic sighting system, which simplifies the configuration of the automatic sighting system.

In addition, since the received light intensity of the return servo light exhibits a bimodal characteristic that is distributed on both sides of the collimation angle position in accordance with the interval between the two-axis collimated server light, it is possible to make each received light output correspond to the direction of deviation. At the same time, the collimation point can be set at the midpoint of the bimodal characteristic based on the relative relationship between the two received light output levels. Therefore, even if each received light signal does not contain any information regarding the angle, or even if the angle of incidence is not detected,
The collimation servo system can be configured with a very simple detection circuit and control circuit based only on the level relationship between two light reception signals.

[Brief explanation of drawings]

Fig. 1 is an overall block diagram of an automatic sighting and ranging system showing an embodiment of the present invention, Figs. 2 and 3 are front views of the optical distance meter and reflector, and Fig. 4 is a layout diagram of the objective lens. , Fig. 5 is an optical path diagram of the collimating servo light, Fig. 6 is a line diagram showing the reflected light flux and the light receiving lens, Fig. 7 is a graph showing an example of the received light level, and Fig. 8 is a diagram showing the angle measurement in the horizontal plane. Diagram showing an example, No. 9
Figure 10 is a diagram showing an example of inclination angle measurement with respect to a horizontal plane. Figure 10 is a diagram showing an example in which the high-intensity part of the collimation servo light is applied to the periphery of a corner cube prism. Figure 11 is a diagram showing an example of the collimation servo A graph showing an example of the received light level when light is projected as shown in Fig. 10, Fig. 12A is a circuit diagram of the main part for detecting the matching point of the output level of the pair, and Fig. 12B is the output level of the pair. Figure C is a waveform diagram explaining the output signal _S1 , Figure 13 is a line diagram showing the state in which reflected light enters the light receiving lens, Figure 14 A is a graph showing the predetermined collimation range. Figure B is a graph showing the collimation range to be detected, Figure C is a waveform diagram explaining the output signal _S1 , Figure D is a waveform diagram showing the output signal _S2. , FIG. 15A is a main circuit diagram showing another example of detecting the collimation range, B and C in the same figure are graphs showing the light reception level of the collimation servo light, D and E in the same figure are output signals S ₃ , Waveform diagrams explaining _S4 , F and G in the figure are waveform diagrams showing output _S5 , Figure 16 is an overall block diagram showing a modification of the automatic sighting and ranging system, and Figure 17 is the arrangement of the objective lens. A layout diagram showing a modification of
Figure 18 is a front view showing a modified example of the reflector, Figure 19 is a front view showing a modified example of the reflector;
The figure is a layout diagram showing an example of a combination of multiple corner cube prisms, Figure 20 is an optical path diagram showing transmission and reflection of each collimating servo light, and Figure 21 is a modification of the arrangement of the light transmission lens. Layout diagram showing, No. 22
The figure shows the arrangement of the light transmitting lens when transmitting a pair of collimated servo lights, Figure 23 is a block diagram of the main parts of the two-light, four-frequency system, and Figure 24 shows the main part block 7 of the two-light, two-frequency system. 25 are block diagrams of the main parts of the two-light single-frequency system. In addition, in the symbols used in the drawings, 2...Collimation device, 2a...Collimation servo circuit, 3...Light wave distance meter, 4...Reflector, 7...Corner cube prism, 8...Horizontal arm , 9... Vertical arm, 11...
...X-axis gear motor, 12...Y-axis gear motor, 1
3a to 13d...Light transmitting lens, 14...Light receiving lens, 15...Light transmitting/receiving unit, 19...Light receiving element, 20a to 20d...Light emitting element, 25a to 25
d... Collimation servo light, 29... Discrimination means, 35...
...objective lens, 39, 40...rotary encoder.

Claims (1)

[Scope of Claims] 1. Light transmitting means for transmitting collimated servo light on two substantially parallel axes to a target point, light receiving means for receiving collimated servo light returned from a reflector at the target point, and each collimation A detection means for detecting a deviation of the optical axis to be collimated based on two received light levels corresponding to the servo light, and a mechanism for correcting the optical axis angle based on the output of the detection means, The collimating servo lights have different carrier frequencies or wavelengths, and the light receiving means for receiving the collimating servo light includes a discriminating means for discriminating the carrier frequency or wavelength to separate and derive received light signals corresponding to the two lights. An automatic sighting device characterized by: