JP7007637B2 - Laser ranging device, laser ranging method and position adjustment program - Google Patents

Description

The present invention relates to a laser ranging device, a laser ranging method and a position adjustment program.

This type of laser ranging device emits a laser beam as transmitted light toward a target (target), receives reflected light from the target, and based on this received light, the distance to the target and the position of the target. It is a device that measures (direction) and. More specifically, the laser ranging device calculates the distance between the laser ranging device and the target from the transmission timing of the transmitted light and the reception timing of the received light. The laser ranging device also calculates the position (direction) of the target based on the received light.

For example, Patent Document 1 includes a pointing detection function in the level detection function of the light receiving system, adjusts the amount of light received to a predetermined value to make the light receiving detection accurate, and enables the device to be compact. The device "is disclosed. The laser ranging device disclosed in Patent Document 1 includes a laser, a transmitting optical system, a light transmitting detector, a receiving optical system, a light receiving detector, a light receiving level detector, a distance measuring counter, a control unit, and a light receiving detector position adjustment. It has a part.

The laser is a light source that outputs, for example, a repetitive pulse laser for distance measurement to a transmission optical system. The transmission optical system shapes the laser beam transmitted from the laser and transmits it to the target. The photodetector detects the timing at which the laser beam is transmitted from the laser and sends the measurement start signal to the ranging counter.

The receiving optical system receives the laser beam reflected from the target and sends it to the light receiving detector. When the light receiving detector detects the beam received via the receiving optical system, it notifies the ranging counter as a measurement stop signal and sends the light receiving beam as a receiving signal to the light receiving level detection unit. In order to receive a laser beam having a constant level value as a reliable measurement stop signal, the light receiving detector position adjusting unit controlled by the control unit adjusts the position of the light receiving detector in the positional relationship with the light receiving spot. The light receiving level detector receives a received signal from the light receiving detector, detects the light receiving level value, and sends it to the control unit as light receiving value data.

The distance measuring counter measures from the time when the measurement start signal is received from the light transmission detector to the time when the measurement stop signal is received from the light receiving detector. The distance measurement counter sends the counter measurement value to the control unit. The control unit has a distance measuring function, a pointing function for tracking a target, and a light receiving level adjusting function for accurate distance measurement. The pointing function is a function that receives a light receiving level value at the detection surface position as light receiving amount data from the light receiving level detecting unit and controls the light receiving detector position adjusting unit to adjust the detection surface position of the light receiving detector.

The control unit receives the counter measurement value from the distance measurement counter and calculates the distance to the target object. When the laser ranging device tracks the target object, the laser sends a pulsed laser beam in response to an instruction from the control unit. The focal point of the light receiving spot is formed on the optical axis via the receiving optical system. The light receiving detector whose surface is the detection surface of the light receiving spot moves in the optical axis direction under the control of the light receiving detector position adjusting unit. At this time, if the detection surface of the light receiving spot is at the focal length of the focal length, the maximum light receiving level can be obtained. However, if the distance is displaced, the focus is defocused, so that the light density of the detection surface is reduced, and the optimum light receiving level value for detecting the light reception can be obtained. By determining the pointing, the optical axis of the light receiving spot is determined at the center position of the light receiving detector in the center, and the light receiving detector is set at the position where the optimum light receiving level value for detecting the light receiving light is obtained.

Various light receiving detectors (detection devices) are used for such a laser ranging device, and one of them is a two-dimensional array element. In order to measure the LOS angle (line-of-sight viewing angle) with an accuracy higher than the resolution of the element using this two-dimensional array element, the following methods are generally known and used. The method is a method of defocusing an originally obtained image and detecting the received light with a plurality of elements to perform measurement with an accuracy higher than the resolution (see, for example, Patent Document 2).

The degree of defocus is determined by the distance measurement distance and the size of the target image. It is necessary to consider the optimum degree of defocusing, and it is necessary to defocus accordingly.

The following patent documents related to the present invention are also known.

Patent Document 3 discloses a highly accurate dimensional measurement method using only one three-dimensional coordinate measuring device. In Patent Document 3, the laser rangefinder modulates the laser beam with a sinusoidal wave, and detects the time difference until the modulated light is reflected by the corner cube mirror attached to the measurement point and returns as the phase difference of the modulated light, and the distance is detected. It is a measurement. The visual sensor captures the reflected beam of the laser and supplies an image of the detected beam to the image processing device. The image processing device calculates the amount of deviation between the center of gravity of the laser beam and the axis center on the screen from the image information, and outputs it to the positioning control device. The positioning control device performs feedback control of the horizontal angle and altitude angle on the turntable on which the laser rangefinder and the visual sensor are mounted so that the amount of deviation input from the image processing device becomes 0, and from the reference point. Precisely measure the horizontal angle and the deflection angle of the altitude angle.

Japanese Unexamined Patent Publication No. 2006-407242 Japanese Patent Publication No. 2008-527357 Japanese Unexamined Patent Publication No. 03-167404

Patent Document 1 does not use a two-dimensional array sensor as a light receiving detector. Therefore, in Patent Document 1, when the maximum light receiving level is exceeded, the focus is blurred to avoid receiving light at the detection surface of the light receiving detector at or above the maximum light receiving level.

Patent Document 3 discloses a technique of sine-wave-modulating a laser beam and detecting a time difference as a phase difference of the modulated light. Further, in Patent Document 3, the reflected beam of the laser is captured by a visual sensor. Therefore, even in Patent Document 3, the two-dimensional array sensor is not used. Further, in Patent Document 3, the positioning control device only performs feedback control of the horizontal angle and the altitude angle with respect to the turntable on which the laser rangefinder and the visual sensor are mounted so that the deviation amount is zero.

Patent Document 2 merely describes forming an image in which the image of the light source is defocused on an array composed of detector elements.

In a laser ranging device that uses a two-dimensional array sensor as a light receiving detector and measures the position and distance of the target based on the reflected light from the target, the angle measurement accuracy is generally the pixel of the two-dimensional array sensor. Limited by size. The following method is known as a method for achieving accuracy smaller than the pixel size. That is, in that method, the array sensor detection surface of the two-dimensional array sensor is shifted from the focal position of the receiving optical system in the optical axis direction, received by a plurality of pixels, and the position of the target is determined by calculating the center of gravity and the like. Achieves an angle measurement accuracy lower than the pixel resolution. This method is used for star trackers and the like.

In this technique, the energy of the received light is divided into multiple pixels. Therefore, this method has a problem that the reception level is lowered during long-distance distance measurement and the optical input is equal to or less than the threshold value (minimum reception sensitivity) of the two-dimensional array sensor.

On the contrary, in the case of short-distance distance measurement, in this method, the dynamic range of reception level detection is out of range due to the input of optical input exceeding the maximum input level per pixel, and a saturated value is output. Therefore, this method has a problem that an error occurs in the position of the center of gravity calculated by software or hardware.

In many of the related preceding laser ranging devices, the position from the receiving optical system to the sensor detection surface is fixed to a certain length. Therefore, it is difficult to deal with the problem of reception level.

The use of avalanche photodiode (APD) arrays with high detection sensitivity is increasing for two-dimensional array sensors in such laser ranging devices. There are two ways to use APD, linear mode and Geiger mode. In the linear mode, the output signal changes linearly with respect to the amount of input light. In Geiger mode, a reverse bias is applied to the very limit of the breakdown to detect a single photon, and whether it is digitally turned on or off is output.

By using a single photon detector with a higher sensitivity Geiger mode, the amount of input light is suppressed and the optical system does not need to be enlarged, which leads to miniaturization of the laser ranging device. A two-dimensional array element in Geiger mode using APD can detect very weak light of several tens of picowats, which corresponds to a single photon level. On the other hand, it is difficult to reduce the element size of a two-dimensional array element in Geiger mode using APD as compared with an element used in related technologies such as a CCD (charge coupled device) camera. Therefore, in the two-dimensional array element in the Geiger mode using APD, there is a limit to the improvement of the resolution (resolution) of the two-dimensional array sensor itself.

An object of the present invention is to provide a laser ranging device, a laser ranging method, and a position adjusting program capable of solving the above problems and adjusting the position of a two-dimensional array sensor having low resolution.

The laser ranging device according to the present invention emits pulsed laser light as transmitted light toward a target, receives the reflected light reflected by the target as received light, and based on the received light, the position of the target and the above. A laser ranging device that measures the distance to a target, including a laser oscillator that oscillates the pulsed laser light; a receiving optical system that includes a convex lens and receives the reflected light as the received light; a plurality of pixels. A two-dimensional array sensor that has an array sensor detection surface that receives image information imaged by the convex lens and outputs reception timing and reception level for each pixel; transmission timing of the laser oscillator and reception. A signal processing unit that calculates the distance from the timing, calculates the position based on the reception level, and outputs a position adjustment signal for adjusting the position of the array sensor detection surface based on the reception level. It has a detection surface position adjusting unit that adjusts a relative position in the optical axis direction between the convex lens and the array sensor detection surface in response to the position adjustment signal.

In the laser ranging method according to the present invention, a pulsed laser beam from a laser oscillator is emitted toward a target as transmitted light, and the reflected light reflected by the target is received as received light by a receiving optical system including a convex lens. The position of the target and the position of the target based on the reception timing and reception level for each pixel output from a two-dimensional array sensor having an array sensor detection surface that receives image information formed by a convex lens and having a plurality of pixels. A laser distance measuring method for measuring the distance to the target, wherein the distance is calculated from the transmission timing of the laser oscillator and the reception timing; the position is calculated based on the reception level. A position adjustment signal for adjusting the position of the array sensor detection surface is sent to the detection surface position adjustment unit that adjusts the relative position in the optical axis direction between the convex lens and the array sensor detection surface. Includes output steps to output and;

The position adjustment program according to the present invention emits pulsed laser light from a laser oscillator as transmitted light toward a target, receives the reflected light reflected by the target as received light by a receiving optical system including a convex lens, and receives the convex lens. Based on the reception timing and reception level for each pixel output from a two-dimensional array sensor having an array sensor detection surface that receives the image information imaged in the above and having a plurality of pixels, the position of the target and the above. A position that causes a computer to adjust a detection surface position adjustment unit that is used in a laser ranging device that measures the distance to a target and adjusts the relative position in the optical axis direction between the convex lens and the array sensor detection surface. An adjustment program for realizing a transmission function for transmitting a position adjustment signal for adjusting the position of the array sensor detection surface to the detection surface position adjustment unit based on the reception level. It is a thing.

According to the present invention, the position of the two-dimensional array sensor having low resolution can be adjusted.

It is a block diagram which shows the whole structure of the laser ranging apparatus which concerns on 1st Embodiment of this invention. It is a figure which shows the main part of the laser ranging apparatus illustrated in FIG. It is a figure which shows the example of the case where the image is defocused and blurred so that it is received by a plurality of elements. FIG. 3 is a flow chart for explaining a position adjustment algorithm executed by a signal processing unit used in the laser ranging device shown in FIG. 1. It is a figure for demonstrating the definition of the moving axis of the array sensor detection surface of the 2D array sensor used in the laser ranging apparatus illustrated in FIG. 1. It is a block diagram which shows the whole structure of the laser ranging apparatus which concerns on 2nd Embodiment of this invention. It is a figure which shows the main part of the laser ranging apparatus illustrated in FIG. It is a block diagram which shows the whole structure of the laser ranging apparatus which concerns on 3rd Embodiment of this invention.

First, the features of the present invention will be described.

The laser ranging device to which the present invention is applied is a light receiving detector having a two-dimensional array sensor, from a target size equal to or less than the pixel resolution of the two-dimensional array sensor, such as a corner cube located far away as a measurement target (target). Receive the reflected light of. Then, the laser ranging device to which the present invention is applied calculates the distance (distance measuring information) between the laser ranging device and the target from the received reflected light, and also performs the ranging information and the two-dimensional array. It is a device that calculates the line of view angle (LOS) angle and attitude angle of the target from the image information of the sensor.

In such a laser ranging device, the present invention is characterized by having a function of improving the angle measurement accuracy by shifting the array sensor detection surface of the two-dimensional array sensor in the optical axis direction from the focal position of the receiving optical system. And. In addition, the present invention autonomously controls the viewing angle / attitude angle accuracy (angle measurement accuracy) and the reception level by feedback-controlling the position of the array sensor detection surface based on the reception level of the two-dimensional array sensor. It is characterized by having a function of optimizing.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the technical scope of the present invention is not limited to the embodiments and should be construed based on the description of the claims.

[First Embodiment]
[Description of configuration]
FIG. 1 is a block diagram showing the entire structure of the laser ranging device 100 according to the first embodiment of the present invention. FIG. 2 is a diagram showing a main part of the laser ranging device 100 according to the first embodiment of the present invention.

The illustrated laser ranging device 100 includes a laser oscillator 110, a transmission / reception system 120, a transmission light detector 130, a reception optical system 140, a reception light detector 150, a signal processing unit 160, and a detection surface. It includes a position adjusting unit 170 and a power supply unit 180. The illustrated photodetector 150 for reception comprises a two-dimensional array sensor. The power supply unit 180 supplies electric power to each unit 110 to 170.

As shown in FIG. 2, the receiving optical system 140 includes a convex lens 142. The two-dimensional array sensor, which is the receiving photodetector 150, has an array sensor detection surface 150a.

The signal processing unit 160 sends a trigger signal to the laser oscillator 110. In response to this trigger signal, the laser oscillator 110 emits a pulsed laser beam. The emitted pulsed laser light is sent to the transmission optical system 120.

The transmission optical system 120 transmits (exits) the received pulsed laser light as transmission light toward a target (not shown). The target has retroreflective properties, such as corner cubes. The pulsed laser light (transmitted light) transmitted from the transmission optical system 120 is reflected as reflected pulsed laser light by this target. Then, the reflected pulsed laser beam returns to the laser ranging device 100 as received light.

The reflected pulsed laser light (received light) is incident on the array sensor detection surface 150a of the two-dimensional array sensor 150, which is a receiving light detector, via the convex lens 142 of the receiving optical system 140.

The distance (distance measuring information) from the laser ranging device 100 to the target can be calculated by counting the round-trip time of the pulsed laser beam. Further, the angle information such as the LOS angle with respect to the target and the attitude angle of the laser ranging device 100 itself can be obtained by software or hardware in the signal processing unit 160 based on the obtained ranging information and the detection position information on the array sensor detector surface 150a. It can be calculated using.

The accuracy of the angle information largely depends on the detection position information of the array sensor detector surface 150a, that is, the position resolution (resolution) of the array sensor detector surface 150a. As described above, in order to improve the position resolution, the array sensor detector surface 150a is shifted from the focal position (imaging position) of the received light in the optical axis direction, and the image is defocused as shown in FIG. It is generally known that the light is received by an element (see the above-mentioned Patent Document 2 and the like).

The amount of deviation of the array sensor detection surface 150a needs to be determined in consideration of the minimum reception sensitivity and dynamic range of the two-dimensional array sensor 150 and the image formation position (focal position), and is the optimum length depending on the distance to the target. Is different. Therefore, in the first embodiment, as shown in FIG. 2, the two-dimensional array sensor 150 is mechanically connected to the detection surface position adjusting unit 170. As a result, the laser ranging device 100 has a function of adjusting the position of the array sensor detection surface 152a in the optical axis direction according to the dynamic range of the reception level, thereby solving the problem of the reception level. Further, in the first embodiment, the signal processing unit 160 calculates the center of gravity point by using software or hardware based on the obtained image information (luminance information). As a result, the laser ranging device 100 feedback-controls the position of the array sensor detection surface 150a to adjust the array sensor detection surface 150a to the optimum position in the optical axis direction.

More specifically, by shifting the array sensor detection surface 150a from the focal point of the receiving optical system 140, the received light is not imaged on the array sensor detection surface 150a and is received by a plurality of pixels of the two-dimensional array sensor 150 as shown in FIG. The energy of light will be divided. As shown in FIG. 2, the two-dimensional array sensor 150 can be mechanically coupled to the detection surface position adjusting unit 170 to set the array sensor detection surface 150a at an arbitrary position.

After receiving with a plurality of pixels, the two-dimensional array sensor 150 outputs the reception timing and the reception level from each pixel to the signal processing unit 160. The signal processing unit 160 calculates the distance between the laser ranging device 100 and the target from the reception timing signal and the transmission timing signal by software processing. Further, the signal processing unit 160 calculates the center of gravity point from the image information (luminance information) of a plurality of pixels, and measures the position of the target to the pixel resolution or less.

Here, the image formation position and the number of reaction pixels of the two-dimensional array sensor 150 differ depending on the distance from the array sensor detection surface 150a to the reception optical system 140, and the control method changes.

First, it is assumed that the distance to the target is a long distance. In this case, the light incident on the receiving optical system 140 can be regarded as substantially parallel light. Therefore, since the position (focal length) for forming an image is obtained from the characteristics of the receiving optical system 140, the amount of deviation of the array sensor detection surface 150a is substantially the same.

Consider a phase in which the laser ranging device 100 is rendezvous (approaching). In this case, it is conceivable that an optical input lower than the minimum reception sensitivity of the two-dimensional array sensor 150 may occur. In such a case, the accuracy of the center of gravity calculation performed by the software or hardware in the signal processing unit 160 deteriorates, so it is necessary to consider the intensity of the optical input. The intensity of the optical input is determined by the distance to the target. Therefore, the laser ranging device 100 according to the present embodiment has a function of adjusting the position of the array sensor detection surface 150a in the optical axis direction according to the minimum reception sensitivity of the reception level, thereby solving the problem of the reception level. ing. That is, the signal processing unit 160 feedback-controls the position of the array sensor detection surface 150a based on the obtained image information (luminance information), and adjusts the array sensor detection surface 150a to the optimum position in the optical axis direction. is doing. After adjusting to the optimum position, the signal processing unit 160 calculates the position of the center of gravity using software or hardware by a method such as the luminance center of gravity method or the difference method.

On the other hand, it is assumed that the distance to the target is short. In this case, it is considered that the received light incident on the receiving optical system 140 has a spreading angle. In such a situation, the image formation position becomes longer as the distance becomes shorter, so it is necessary to perform feedback control according to the distance measurement value. Further, in the case of distance measurement at a short distance, it is conceivable that an optical input exceeding the dynamic range of the two-dimensional array sensor 150 is generated, and it is conceivable that the accuracy of the center of gravity calculation in the signal processing unit 160 is deteriorated. At this time, as in the case of a long distance, the laser ranging device 100 according to the present embodiment has a function of adjusting the position of the array sensor detection surface 150a in the optical axis direction according to the dynamic range of the reception level. , Solving the reception level problem.

[Description of operation]
Next, the operation of the laser ranging device 100 will be described with reference to FIG. The laser ranging device 100 according to the first embodiment of the present invention is based on the basic principle of calculating the distance to the target by counting the round-trip time of the pulse laser.

In the laser ranging device 100 that has reached the ranging start position, a trigger signal is sent from the signal processing unit 160, and a pulsed laser beam is emitted from the laser oscillator 110. A part of the pulsed laser light is transmitted to the transmission light detector 130, and the rest is transmitted to the target as transmission light via the transmission optical system 120. The photodetector 130 for transmission transmits the transmission timing to the signal processing unit 160, and the transmission timing signal is used as the start of distance measurement. Further, the transmission optical system 120 shapes the laser pulse light into a beam spread so as to include the viewing angle of the two-dimensional array sensor 150 of the receiving unit.

Now, suppose that there is a target having retroreflection characteristics such as a corner cube within the viewing angle of the two-dimensional array sensor 150. In this case, a part of the transmitted light radiated to the target is reflected in the direction in which the transmitted light comes, and this reflected light is received as the received light by the receiving optical unit system 140. The receiving optical system 140 propagates the received light to the array sensor detection surface 150a of the two-dimensional array sensor 150.

At this time, if the array sensor detection surface 150a is out of focus of the receiving optical system 140, the received light is not imaged on the array sensor detection surface 150a, and the energy of the received light is divided into a plurality of pixels of the two-dimensional array sensor 150. Will be. As shown in FIG. 2, the two-dimensional array sensor 150 is mechanically coupled to the detection surface position adjusting unit 170. Therefore, the array sensor detection surface 150a can be adjusted in the optical axis direction by the detection surface position adjusting unit 170 and set to an arbitrary position. After receiving with a plurality of pixels, the two-dimensional array sensor 150 outputs the reception timing and the reception level from each pixel to the signal processing unit 160.

Next, the position adjustment algorithm executed by the signal processing unit 160 will be described with reference to FIG. Here, the moving axis of the array sensor detection surface 150a is defined as shown in FIG.

The signal processing unit 160 moves the array sensor detection surface 150a to the initial position X ₀ in advance (step S101). When the laser ranging device 100 reaches the ranging position, the signal processing unit 160 starts ranging by issuing a trigger signal (step S102).

At this time, it is assumed that the two-dimensional array sensor 150 has a minimum reception sensitivity or less and cannot be detected (N in step S103). In this case, the signal processing unit 160 emits a position adjustment signal to move the array sensor detection surface 150a to the focal position (origin) of the receiving optical system 140 (step S104). After that, the signal processing unit 160 performs measurement again (step S105), and if detection is not possible (N in step S106), the signal processing unit 160 transmits a distance measurement impossible signal to the host system 200 (step S107). ). After that, the signal processing unit 160 performs measurement again (step S105) and determines whether or not it can be detected (N in step S106).

If the result of the remeasurement can be detected (Y in step S106), the signal processing unit 160 moves the array sensor detection surface 150a by a certain amount in the + direction of the X axis (step S108) and performs remeasurement. (Step S109). If detection is not possible here (N in step S110), the signal processing unit 160 returns the array sensor detection surface 150a to the negative direction of the X-axis by the amount of movement (step S111) and remeasures the element. The distance is calculated from the reception timing and reception level for each (step S112). If it can be detected (Y in step S110), the signal processing unit 160 subsequently determines whether the position X of the array sensor detection surface 150a is at the initial position X ₀ (step S113). When X = X ₀ (Y in step S113), the signal processing unit 160 ends the position adjustment and calculates the distance measurement value and the like from the reception timing and reception level for each element (step S112). When X ≠ X ₀ (N in step S113), the signal processing unit 160 moves the array sensor detection surface 150a by a certain amount + direction again (step S108), and measures again (step S109).

When the distance can be measured in the first distance measurement (Y in step S103), the signal processing unit 160 determines whether or not there is an input exceeding the dynamic range (step S114). When there is an input equal to or greater than the dynamic range (N in step S114), the signal processing unit 160 moves the array sensor detection surface 150a in the negative direction of the X-axis by a certain amount (step S115), and performs measurement again (step S115). Step S116), the same determination is made (step S117). When the input is below the dynamic range in all the reaction elements (Y in step S114 and Y in step S114), the signal processing unit 160 ends the position adjustment and distances from the reception timing signal and the transmission timing signal. Is calculated (step S112). Further, the signal processing unit 160 calculates the center of gravity point from the image information (brightness information) of a plurality of pixels using software or hardware, and measures the position of the target to the pixel resolution or less (step S112). Finally, the signal processing unit 160 transmits the calculation result to the host system 200 (step S118).

[Explanation of effect]
Next, the effect of the first embodiment will be described.

The first effect is that by controlling the position of the array sensor detection surface 150a according to the distance measurement distance, problems on the element side such as the dynamic range and the minimum reception sensitivity of the two-dimensional array sensor 150 can be solved.

The second effect is that the angle measurement accuracy higher than the resolution can be expected by receiving with a plurality of elements of the two-dimensional array sensor 150.

[Second Embodiment]
[Description of configuration]
Next, a second embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 6 is a block diagram showing the entire structure of the laser ranging device 100A according to the second embodiment of the present invention. FIG. 7 is a diagram showing a main part of the laser ranging device 100A according to the second embodiment of the present invention.

The illustrated laser ranging device 100A has the same configuration as the laser ranging device 100 shown in FIG. 1 and operates except that the location of the detection surface position adjusting unit 170 is different. For the sake of brevity, only the differences from the first embodiment will be described below.

In the first embodiment, the array sensor detection surface 150a of the two-dimensional array sensor 150 is moved by the detection surface position adjusting unit 170.

On the other hand, in the second embodiment, the receiving optical system 140 is moved by the detection surface position adjusting unit 170 to change the imaging position.
Since the laser ranging device 100A operates in the same manner as the laser ranging device 100 according to the first embodiment described above, the description thereof will be omitted.

Further, the laser ranging device 100A also has the same effect as the laser ranging device 100 according to the first embodiment described above.

[Third Embodiment]
[Description of configuration]
Next, a third embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 8 is a block diagram showing the entire structure of the laser ranging device 100B according to the third embodiment of the present invention.

The illustrated laser ranging device 100B has the same configuration as the laser ranging device 100 shown in FIG. 1 except that the photodetector 130 for transmission is omitted and the operation of the signal processing unit is different. It works. Therefore, a reference code of 160A is attached to the signal processing unit. For the sake of brevity, only the differences from the first embodiment will be described below.

In the first embodiment, the transmission timing is measured by using the transmission optical detector 130, and the distance measurement is started.

On the other hand, in the third embodiment, the delay in the laser oscillator 110 is corrected inside the signal processing unit 160A, and the distance measurement is started with the trigger signal from the signal processing unit 160A.

By adopting such a configuration, the transmission photodetector 130 can be eliminated.

Since the laser ranging device 100B operates in the same manner as the laser ranging device 100 according to the first embodiment described above, the description thereof will be omitted.

Further, the laser ranging device 100B also has the same effect as the laser ranging device 100 according to the first embodiment described above.

Although not shown, the signal processing units 160 and 160A can be realized by an information processing device including a processor, a program memory, and a work memory for temporarily storing data.

In the signal processing units 160 and 160A realized by such an information processing apparatus, a position adjustment program for executing the position adjustment algorithm shown in FIG. 4 is stored in the program memory. Then, the processor executes the process according to the position adjustment program stored in the program memory, thereby realizing the functions of the signal processing units 160 and 160A that execute the position adjustment algorithm shown in FIG.

Although embodiments and examples of the present invention have been described above with reference to the drawings, those skilled in the art can use other similar embodiments and examples, and from the present invention. It should be noted that the form can be changed or added as appropriate without deviation.

INDUSTRIAL APPLICABILITY The present invention can be used for a mission to recognize a position / posture in a distance measuring device using a laser or the like.

100, 100A, 100B Laser ranging device 110 Laser oscillator 120 Transmission optical system 130 Transmission optical detector 140 Reception optical system 142 Convex lens 150 Reception optical detector (two-dimensional array sensor)
160, 160A Signal processing unit 170 Detection surface position adjustment unit 180 Power supply unit 200 Upper system

Claims (9)

The pulsed laser light is emitted toward the target as transmitted light, the reflected light reflected by the target is received as received light, and the distance between the target position and the target is measured based on the received light. It is a laser ranging device,
A laser oscillator that oscillates the pulsed laser beam and
A receiving optical system including a convex lens and receiving the reflected light as the received light,
A two-dimensional array sensor that has a plurality of pixels, has an array sensor detection surface that receives image information imaged by the convex lens, and outputs reception timing and reception level for each pixel.
The distance is calculated from the transmission timing and the reception timing of the laser oscillator, the position is calculated based on the reception level, and the position for adjusting the position of the array sensor detection surface is adjusted based on the reception level. A signal processing unit that outputs adjustment signals and
A detection surface position adjusting unit that adjusts the relative position in the optical axis direction between the convex lens and the array sensor detection surface in response to the position adjustment signal.
Laser ranging device with. The laser ranging device according to claim 1, wherein the detection surface position adjusting unit is mechanically coupled to the two-dimensional array sensor. The laser ranging device according to claim 1, wherein the detection surface position adjusting unit is mechanically coupled to the receiving optical system . The present invention according to any one of claims 1 to 3, further comprising a transmission optical detector that detects a part of the pulsed laser light oscillated from the laser oscillator and transmits the transmission timing to the signal processing unit. The laser ranging device described. Based on the reception level, the signal processing unit outputs the position adjustment signal so that the intensity of the optical input received by the two-dimensional array sensor is equal to or higher than the threshold value of the two-dimensional array sensor and is within the dynamic range. The laser ranging device according to any one of claims 1 to 4, which outputs the laser ranging device. The pulsed laser light from the laser oscillator is emitted toward the target as transmission light, the reflected light reflected by the target is received as reception light by the receiving optical system including the convex lens, and the image information formed by the convex lens is received. The distance between the target position and the target is measured based on the reception timing and reception level for each pixel output from the two-dimensional array sensor having the receiving array sensor detection surface and having a plurality of pixels. Laser distance measurement method
A distance calculation step for calculating the distance from the transmission timing and the reception timing of the laser oscillator, and
A position calculation step for calculating the position based on the reception level, and
An output step for outputting a position adjustment signal for adjusting the position of the array sensor detection surface to the detection surface position adjustment unit for adjusting the relative position in the optical axis direction between the convex lens and the array sensor detection surface, and an output step.
Laser ranging methods including. In the output step, the position adjustment signal is output so that the intensity of the optical input received by the two-dimensional array sensor is equal to or higher than the threshold value of the two-dimensional array sensor and is within the dynamic range based on the reception level. do,
The laser ranging method according to claim 6. The pulsed laser light from the laser oscillator is emitted toward the target as transmission light, the reflected light reflected by the target is received as reception light by the receiving optical system including the convex lens, and the image information formed by the convex lens is received. The distance between the target position and the target is measured based on the reception timing and reception level for each pixel output from the two-dimensional array sensor having the receiving array sensor detection surface and having a plurality of pixels. This is a position adjustment program that allows a computer to adjust the detection surface position adjustment unit that adjusts the relative position in the optical axis direction between the convex lens and the array sensor detection surface, which is used in the laser ranging device.
A position adjustment program for realizing a transmission function of sending a position adjustment signal for adjusting the position of the array sensor detection surface to the detection surface position adjustment unit to the computer based on the reception level. The transmission function is provided to the computer so that the intensity of the optical input received by the two-dimensional array sensor is equal to or higher than the threshold value of the two-dimensional array sensor and is within the dynamic range based on the reception level. The position adjustment program according to claim 8, wherein an adjustment signal is transmitted.

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