JP2009270954A - Range finder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a range finder used for short distance measurement to long distance measurement by itself. <P>SOLUTION: This range finder for measuring the distance to the object includes: an invisible light emitting means for emitting invisible light for measuring the distance to the object; a visible light emitting means for emitting visible light for pointing the object; a light projection optical system for projecting the invisible light and the visible light toward the object at the same optical axis; a sighting optical system for seeing and sighting the object sharing the optical axis towards the object with the light projection optical system; a light receiving means for receiving the reflected light of the invisible light from the object and outputting a light receiving signal; and a controlling means for performing control so that the distance from the time from the light emission to the light receiving is determined based on the light receiving signal output from the light receiving means, and that light is emitted by switching between the invisible light emitting means and visible light emitting means in measuring the distance to the object and in pointing the object. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a distance meter that measures a distance to an object.

  Conventional devices have respective rangefinders that have different light emitting units depending on the objects to be measured at short and long distances. In the case of short-distance measurement, there is an apparatus in which an aiming telephoto lens for aligning a measurement point with an object is omitted, and a measurement point on the object that is exposed to visible laser light can be directly visually confirmed. In the case of long-distance measurement, the reflected light (received signal level) from the object to be measured becomes small at a long distance, so the influence of ambient light noise is prevented and long-distance measurement is possible. There is a device equipped with an aiming telephoto lens (with a reticle and a display unit) for aligning a measurement point with an object using infrared) laser light.

  On the other hand, there is also a disclosure of a distance meter that includes a distance measuring LED (light emitting diode) and a semiconductor laser that emits a sighting visible light (Patent Document 1).

JP-A-7-35856

  However, the distance meter disclosed in Patent Document 1 is not necessarily a distance meter for realizing both functions of short distance measurement and long distance measurement. In short distance measurement and long distance measurement, the method for aligning the measurement point with the light emitting unit and the object to be measured differs depending on the purpose of use. There was a problem that was difficult.

  The present invention is applied to a distance meter for measuring a distance to an object, and emits invisible light for emitting invisible light for measuring the distance to the object, and visible light for indicating the object. Look at the visible light emitting means, the projecting optical system that projects invisible light and visible light to the target with the same optical axis, and the target that shares the optical axis toward the target and the projecting optical system. Aiming optical system for aiming, light receiving means for receiving reflected light of invisible light from the object and outputting a light receiving signal, and time from light emission to light receiving based on the light receiving signal output from the light receiving means Control to obtain the distance to the object, and control to switch the invisible light emitting means and the visible light emitting means to emit light when measuring the distance to the object and pointing to the object And comprising means Is shall.

  Since the present invention is configured as described above, it is possible to configure a distance meter for a short distance to a long distance with a single unit. In addition, even at a short distance or a long distance, it is possible to accurately aim at the object and measure the distance to the object with high accuracy and reliability.

-First embodiment-
FIG. 1 is a diagram showing an internal configuration of the laser rangefinder according to the first embodiment of the present invention. One laser distance meter of this embodiment can measure the distance of an object from a short distance to a long distance. For this reason, it is possible to point an object at a short distance with a pointer using a visible laser beam, and aim the object at a medium to long distance using an aiming optical system. The distance to the object can be measured.

  As shown in FIG. 1, there are a light transmitting lens 4, a light receiving lens 5, an eyepiece 9, a POWER button 10, a distance measuring button 11, a pointer button 12, an external display on the outside of the main body 1 of the laser distance meter of the present embodiment. A unit (LCD) 18 is provided. Inside, invisible laser light emitting part 2, prism 3, band pass filter 6, light receiving part (APD, avalanche photodiode) 7, internal display part (transmissive LCD) 8, visible laser (visible light) light emitting part 15, optical path switching A mirror 16, a mirror driving unit 17, a control board 13, a power source 19 and the like are provided. The power source 19 is composed of a battery.

  A sighting optical system (a collimating optical system, a telephoto optical system) is formed by the light transmission lens 4, the internal display unit (transmission LCD) 8, and the eyepiece lens 9 for positioning the object. The internal display unit (transparent LCD) 8 is transparent when the power is off, but when the power is on, the alignment reticle, measurement distance result, m / yard unit, remaining battery level, and the like are displayed. Items other than the reticle are displayed on the external display unit.

  The light transmission lens 4 condenses and projects the visible laser light from the visible laser light emitting unit 15 and the visible laser light from the invisible laser light emitting unit 2 so as to collimate toward the object to be measured along the same optical axis ( A light projecting optical system (emitting optical system) is formed. The aiming optical system and the projecting optical system share an optical axis directed to the object.

  FIG. 2 is an electrical block diagram, and FIG. 3 is a flowchart. The operation of the laser distance meter will be described with reference to the electric block diagram of FIG. 2 and the flowchart of FIG. The process of the flowchart of FIG. 3 is performed by the CPU 20 executing a predetermined program.

  The CPU 20 controls ON / OFF of light emission of the invisible laser light emitting unit 2 through the light emitting circuit 21, controls ON / OFF of light emission of the visible laser light emitting unit 15 through the light emitting circuit 22, and controls the mirror driving unit 17. The insertion / retraction of the optical path switching mirror 16 with respect to the optical axis is controlled. That is, the CPU 20 performs light emission control of invisible laser light, light emission control of visible laser light, and mirror insertion / retraction control. Furthermore, the CPU 20 also performs distance calculation and display control, which will be described later.

  When the POWER button 10 is pressed, the power is turned on (S1), and when the power button is pressed again, the power is turned off. It is determined whether or not the pointer button 12 is pressed while the power is on (S2). If not, the ranging circuit such as the internal display unit 8, the external display unit 18, the light receiving unit 7 or the signal processing circuit 24 is used. Are turned on (S3). In this state, when looking through the eyepiece 9, the enlarged elephant to be measured and the alignment reticle displayed on the transmissive display unit 8 appear to overlap, so that the object to be measured can be aimed.

  When the distance measuring button 11 is pressed while aiming at the object, laser light is emitted (emitted) from the invisible laser light emitting unit 2 (S5), and is projected onto the distance measuring object through the prism 3 and the light transmitting lens 4. The reflected laser light from the object is received by the light receiving unit 7 only in a necessary wavelength region by the light receiving lens 5 and the band pass filter 6 (S6). The received light signal is distance-calculated by the signal processing circuit 24 and the CPU 20 (S7), and the distance is displayed on the internal display unit 8 and the external display unit 18 (S8). That is, the time from the emission of the invisible laser light for distance measurement to the light reception is measured based on the light reception signal, and the distance to the object is calculated based on the measured time.

  Note that only when the distance measuring button 11 is being pressed, the invisible laser light emitting unit 2 is turned on and distance measurement is performed. When the distance measuring button 11 is released, the invisible laser light emitting unit 2 is turned off and distance measurement is stopped. A signal from the distance measurement button 11 is input to the CPU 20, and the CPU 20 controls ON / OFF of light emission of the invisible laser light emitting unit 2.

  On the other hand, when the pointer button 12 is pressed, it is determined whether or not the pointer button 12 is pressed in step S2, and the optical path switching mirror 18 is rotated about the axis 31 by the mirror driving unit 17 (solid line position), and visible light emission is performed. The unit 15 is turned on (S10), and the visible light from the visible light emitting unit 15 is projected onto the distance measuring object. As a result, the aiming position of the distance measuring object can be viewed.

  When the visible light emitting unit 15 is ON, ranging circuits such as the invisible laser emitting unit 5, the internal display unit 8, the external display unit 18, the light receiving unit 7, and the signal processing circuit 24 are turned off (S11). That is, the measurement of the distance of the object is set to a non-operation state. When the pointer button 12 is pressed again, the optical path switching mirror 18 is rotationally moved to the original position (dotted line) by the mirror driving unit 17 and the visible light emitting unit is turned off (S10). Thereby, the measurement of the distance of the target is made operable. Specifically, the distance of the object is measured by pressing the distance measuring button 11 in this state.

  Further, when the distance measuring button 11 is ON, the visible light emitting unit 15 is controlled to be always OFF (S4, S12). That is, when the distance measuring button 11 is turned on while the visible light emitting unit 15 is ON, it is determined whether or not the visible light emitting unit 15 is ON (S4). It becomes OFF (S12), and after it becomes OFF, the invisible laser is turned ON (S5).

  The invisible laser light emitting unit 2, the light emitting circuit 21, the visible laser light emitting unit 15, the visible laser light emitting circuit 22, the optical path switching mirror 16, the mirror driving unit 17, the internal display unit 8, and the external display unit 18 are controlled by the CPU 20.

Next, the case where the apparatus is used will be described.
(1) When using an eyepiece reticle (example: using the device by hand, long-distance ranging)
When looking into the eyepiece 9 and pressing the POWER button 10, a reticle is displayed on the internal display unit 8. Next, when the center of the reticle is aligned with the object to be measured and the distance measuring button 11 is pressed, invisible laser light is emitted (projected) on the object, reflected light is received and processed, and the distance measurement result is displayed on the display unit. (Internal, external).

(2) When using a pointer (Example: When the device is fixed on a tripod or used by hand, the distance is measured)
When the POWER button 10 is pressed and the pointer button 12 is further pressed, visible laser light is emitted to the object. In this case, the pointer button 12 does not need to be kept pressed. Visually align the device with the distance measuring point. Next, when the distance measuring button 11 is pressed, the visible laser light is turned off, the invisible laser light is emitted to the object, the reflected light is received and processed, and the distance measurement result is displayed on the external display unit (LCD) 18.

According to the present embodiment described above, the following operational effects can be obtained.
(1) Conventionally, it is possible to use one laser rangefinder for both short distance and long distance (including medium distance). In addition, the laser projection optical system (exiting optical system) is shared so that the projection optical axis is the same, and the two light emitting units can be switched and used. Is possible.

(2) Since the two light emitting units are switched and used, each light emission does not adversely affect other light emission. For example, when the invisible laser light emitting unit 2 is turned on and the distance is measured, if the visible light is also turned on, the reflected light of the visible light is incident on the light receiving unit 7 and noise is received in the original reception of the invisible light. Adversely affected. As a result, the accuracy of measuring the distance to the object is lowered, and the reliability is lowered. However, by adopting the configuration as in the present embodiment, the accuracy of measurement of the distance to the object is increased and the reliability is also increased. In addition, since any unnecessary light emitting unit is turned off, the power consumption is reduced, the heat generation of the apparatus is further reduced, and the reliability of the circuit operation is increased.

(3) Since the optical axis of the light projecting optical system and the aiming optical system is shared, invisible light is accurately projected (irradiated) on the aimed object, and highly reliable distance measurement is possible.

(4) When the visible laser emitting unit 15 emits visible light, the optical path switching mirror 16 is inserted into the optical axis of the light projecting optical system. When the visible laser emitting unit 15 does not emit visible light, the optical path switching mirror is used. 16 is retracted from the optical axis of the light projecting optical system. Accordingly, when the visible laser light emitting unit 15 does not emit visible light and the invisible laser light emitting unit 2 emits invisible light to measure the distance of the object, the invisible light is not obstructed by the optical path switching mirror 16. Not attenuated. Further, the reflected light of the visible light does not enter the light receiving unit 7 without projecting the visible light. As a result, it is possible to measure the distance to an object with high accuracy and high reliability.

(5) Since the optical path switching mirror 16 is inserted into and retracted from the optical axis of the light projecting optical system by a rotation operation around the axis 31, the configuration and control of the optical path switching means are simple.

(6) When the power of the laser distance meter is turned on with the POWER button 10, the visible light of the visible laser emitting unit 15 is emitted, so that the laser distance meter can be used as a pointer immediately after the power is turned on. . When the distance measuring button 11 is further turned on, the visible laser light emitting unit 15 is controlled to stop emitting visible light, so that the visible light from the pointer has an adverse effect on the distance measuring operation to the object. Does not affect. Thereby, ranging to a highly reliable target object is attained.

(7) Since the start / stop of invisible light emission of the invisible laser emission unit 2 is controlled in conjunction with the ON / OFF of the distance measuring button 11, unnecessary invisible light emission is eliminated and the power consumption of the laser distance meter is eliminated. Is reduced. This increases the battery life of the power source 19 of the laser distance meter.

-Second Embodiment-
FIG. 4 is a diagram illustrating a configuration of a laser rangefinder according to the second embodiment. The optical path switching mirror 16 in FIG. 1 is replaced with a half mirror 25 and fixed. The operation is the same as that of the first embodiment except that the optical path switching mirror drive is deleted. Other configurations are the same as those in FIGS. 1 and 2 of the first embodiment.

  In the second embodiment, when the distance measurement button is pressed to measure the distance, a mode in which the distance measuring circuit is operated only when the invisible laser light is emitted by alternately driving the two light emitting units ON / OFF is possible. Thus, since the pointer is not erased (to be precise, it blinks), it becomes possible to realize a device that is easier to use.

  FIG. 5 is a diagram illustrating a flowchart of the second embodiment. The same step numbers are assigned to the same processes as those in the first embodiment. The process of the flowchart of FIG. 5 is performed by the CPU 20 executing a predetermined program.

  As in the first embodiment, when the distance measuring button 11 is pressed while aiming at the object, first, laser light is emitted (emitted) from the invisible laser light emitting unit 2 (S21), and the prism 3 and the light transmission lens 4 are moved. It is projected onto the object for distance measurement. The reflected laser light from the object is received by the light receiving unit 7 only in a necessary wavelength region by the light receiving lens 5 and the band pass filter 6 (S6). The received light signal is distance-calculated by the signal processing circuit 24 and the CPU 20 (S7), and the distance is displayed on the internal display unit 8 and the external display unit 18 (S8).

  Next, invisible light from the invisible laser light emitting unit 2 is turned off (S22), distance measuring circuits such as the light receiving unit 7 and the signal processing circuit 24 are turned off (S23), and visible light from the visible laser light emitting unit 15 is turned on. (S24). As a result, the pointer operation is resumed, the object to be measured is pointed (pointed) by the visible laser beam, and the object to be measured can be visually confirmed. Thereafter, when a predetermined time has elapsed (S25), the process returns to step S3 and is repeated.

According to the second embodiment described above, the following operational effects can be obtained.
(1) While the distance measuring button 11 is pressed, that is, while the object is being measured, the invisible light from the invisible laser light emitting unit 2 and the visible light from the visible laser light emitting unit 15 are alternately emitted. Therefore, it is possible to perform distance measurement to a highly accurate and reliable object while visually recognizing which object is the object of distance measurement.

  To be exact, while the invisible light from the invisible laser light emitting unit 2 is actually emitted to measure the distance, the visible light from the visible laser light emitting unit 15 is stopped as in the first embodiment. Therefore, the ranging accuracy is high and reliable as in the first embodiment. When it is considered that the object is being measured while the distance measurement button 11 is being pressed macroscopically, the object is pointed to by the pointer while the object is being measured. Accurate and reliable distance measurement similar to that of the first embodiment can be performed while accurately grasping.

-Modification-
The laser distance meter according to the above-described embodiment can be modified as follows.
(1) In the said embodiment, the invisible laser light emission part 2 and the visible laser light emission part 15 demonstrated by the example of the light source which light-emits a laser beam. However, the measurement light and the pointer light are not necessarily limited to laser light. Other light sources may be used. For example, a light emitting diode (LED) or a super luminescent diode (SLD) may be used. That is, any light source that emits light suitable for distance measurement or any light source that emits light suitable for a pointer can be used.

(2) The distance meter described above may be any type of distance meter such as a portable type or a stationary type. In addition, it may be used for leisure purposes such as golf, used for surveying or building construction work, or used for any purpose.

  Although various embodiments and modifications have been described above, the present invention is not limited to these contents. Other embodiments conceivable within the scope of the technical idea of the present invention are also included in the scope of the present invention. Various combinations of the above-described embodiments and modifications are also valid as long as they are within the scope of the technical idea of the present invention.

It is a figure which shows the internal structure of the laser rangefinder of 1st Embodiment. It is an electrical block diagram of the laser rangefinder of a 1st embodiment. It is a figure which shows the flowchart of the laser distance meter of 1st Embodiment. It is a figure which shows the internal structure of the laser rangefinder of 2nd Embodiment. It is a figure which shows the flowchart of the laser distance meter of 2nd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Laser rangefinder 2 Invisible laser light emission part 3 Prism 4 Light transmission lens 5 Light reception lens 6 Band pass filter 7 Light reception part 8 Internal display part 9 Eyepiece 10 POWER button 11 Distance measurement button 12 Pointer button 13 Control board 15 Visible laser Light emitting unit 16 Optical path switching mirror 17 Mirror driving unit 18 External display unit 19 Power source 19
20 CPU
21, 22 Light emitting circuit 24 Signal processing circuit 25 Half mirror

Claims (6)

A distance meter that measures the distance to an object,
Invisible light emitting means for emitting invisible light for measuring the distance to the object;
Visible light emitting means for emitting visible light for pointing to the object;
A light projecting optical system that projects the invisible light and the visible light on the same optical axis toward an object;
An aiming optical system for sighting and aiming at an object sharing an optical axis directed toward the object with the projecting optical system;
A light receiving means for receiving the reflected light of the invisible light from the object and outputting a light reception signal;
In the case where the distance from the light emission to the light reception is calculated based on the light reception signal output from the light receiving means and the distance to the object is calculated, and the distance to the object is measured and the object is indicated. A distance meter comprising: a control means for controlling the invisible light emitting means and the visible light emitting means to switch and emit light. The distance meter according to claim 1,
An optical path changing unit that is inserted into the optical axis of the light projecting optical system to reflect the visible light emitted by the visible light emitting unit and project the light from the light projecting optical system toward an object; In addition,
When the visible light emitting means emits the visible light, the control means controls the optical path changing means to be inserted into the optical axis of the light projecting optical system and performs control for obtaining a distance to the object. When the visible light emitting means stops and the visible light emitting means does not emit the visible light, the optical path changing means is controlled to be retracted from the optical axis of the light projecting optical system and the control for obtaining the distance to the object is operable. A distance meter characterized by The distance meter according to claim 2,
The distance meter is characterized in that the optical path changing means is inserted into or retracted from the optical axis of the light projecting optical system by a rotation operation about a predetermined axis. The distance meter according to any one of claims 1 to 3,
A power on / off instructing member for instructing power on / off of the distance meter;
A distance measurement instruction member for instructing start and stop of measurement of the distance to the object,
The control means causes the visible light emitting means to emit the visible light in conjunction with an on instruction of the power on / off instructing member, and emits the visible light in conjunction with an off instruction of the power on / off instructing member. And when the visible light is emitted in conjunction with an on instruction of the power on / off instructing member, further in conjunction with an instruction to start measuring the distance to the object by the distance measuring instructing member. A distance meter controlled to stop the emission of visible light. The rangefinder according to any one of claims 1 to 4,
A distance measurement instructing member for instructing to disclose and stop the measurement of the distance to the object;
The control means causes the invisible light emitting means to emit the invisible light in conjunction with an instruction to start measuring the distance to the object by the distance measurement instruction member, and to the object by the distance measurement instruction member. A distance meter that controls to stop the emission of the invisible light in conjunction with an instruction to stop the distance measurement. The rangefinder according to any one of claims 1 to 4,
A distance measurement instructing member for instructing to disclose and stop the measurement of the distance to the object;
The control means controls the invisible light emitting means and the visible light emitting means to emit light alternately when instructed to start the measurement of the distance to the object by the distance measurement instructing member, and the invisible light emitting means. A distance meter characterized in that control is performed so as to obtain a distance to an object only when the light emitting means emits invisible light.

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