JPH09211127A - Distance measuring device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a distance measuring device wherein the irradiation spot of collimating light is clear by emitting on-and-off collimating light with a collimating means in a specified direction. SOLUTION: When a drive circuit 24 receives a modulation instruction for collimation, a rectangular wave signal is output to a laser diode 25, and laser light generated from the laser diode 25 is turned on and off. A measuring man collimates an object with on-and-off collimating laser light. A microprocessor 23 outputs a measuring modulation instruction to the drive circuit 24, which modulates the laser light generated from a laser circuit 25 by a sine wave. A light receiving element 27 photoelectrically converts measuring laser light into a light receiving signal. Next, the light receiving signal is received with a phase comparison circuit 29 through an amplifier 28, in which a phase difference between a laser modulation signal and the light receiving signal is measured. And the phase comparison circuit 29 outputs the measured phase difference to a microprocessor 23, which calculates a distance up to an object to be measured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a distance measurement for transmitting aiming light and a measuring wave in a predetermined direction and measuring a distance to a target located in the predetermined direction based on a propagation delay of a returning measuring wave. More particularly, the present invention relates to a distance measuring device that emits blinking aiming light.

[0002]

2. Description of the Related Art Generally, there is known a distance measuring device which transmits a measuring wave and measures the distance from the propagation delay of the returning measuring wave. In the conventional distance measuring device, US Pat.
As described in Japanese Patent No. 190, a measurer looks into a finder for collimation, determines a measuring object, and measures the distance.

As another conventional example, a distance measuring device that irradiates a laser beam for aiming is also well known. In this distance measuring device, continuous light is emitted as a laser beam for aiming. The measurer uses this aiming laser light to aim at the object to be measured and measure the distance.

[0004]

In the conventional distance measuring device, continuous laser light is used as the aiming laser light. Therefore, in a bright place such as outdoors or in a place where the object to be measured is distant, the irradiation spot of the aiming laser beam is not clear, and there is a problem that it is difficult to aim at the object to be measured.

Further, since the irradiation spot of the aiming laser light is unclear, conventionally, the measurer shakes the distance measuring device to search for the aiming laser light irradiation spot, and it takes time for aiming. It took a while. Also, to solve the problem that the irradiation spot is unclear, the intensity of the aiming laser beam should be increased, but the use of high intensity laser beam involves a dangerous side, and the problem is easily solved. I couldn't.

Furthermore, since continuous laser light is used as the aiming laser light, there is a problem that a large amount of power is consumed even when aiming. SUMMARY OF THE INVENTION It is an object of the present invention to provide a distance measuring device in which the irradiation spot of aiming light is clear in order to solve the above-mentioned problems.

[0007]

FIG. 1 is a block diagram showing the principle of the present invention.

According to the present invention, aiming means 1 for emitting aiming light in a predetermined direction and transmitting means 2 for transmitting a measurement wave in a predetermined direction.
And a receiving means 3 for receiving a measurement wave returning from a predetermined direction,
Based on the propagation delay of the measurement wave received by the receiving means 3,
In the distance measuring device provided with the distance calculation means 4 for calculating the distance to the target object located in the predetermined direction, the aiming means 1 emits blinking aiming light in the predetermined direction.

(Operation) In the distance measuring device of the present invention, the aiming means 1 emits aiming light which blinks in a predetermined direction. The measurer can use the blinking aiming light to aim at a target located in a predetermined direction.

Next, the measurer causes the transmitting means 2 to transmit the measurement wave in a predetermined direction while aiming at the target. The measurement wave transmitted from the transmitting means 2 is reflected by the target and is received by the receiving means 3. The distance calculating means 4 calculates the distance to the target based on the propagation delay of the measurement wave received by the receiving means 3.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 2 is a configuration diagram of an embodiment corresponding to the present invention. In FIG. 2, the switch 2 is provided on the main body 21.
2a and a switch 22b are arranged. Switch 22a
Of the switch 22b is connected to the first input terminal of the microprocessor 23, and the output terminal of the switch 22b is connected to the second input terminal of the microprocessor 23.

The first output terminal of the microprocessor 23 is connected to the laser diode 25 and the first input terminal of the phase comparison circuit 29 via the drive circuit 24. On the other hand, the lens 26a is arranged on the irradiation axis of the laser light generated from the laser diode 25. A lens 26b is arranged adjacent to the lens 26a, and a light receiving element 27 is arranged on the irradiation axis of the lens 26b.

Further, the output terminal of the light receiving element 27 is connected to the second input terminal of the phase comparison circuit 29 via the amplifier 28. The output terminal of the phase comparison circuit 29 is connected to the third input terminal of the microprocessor 23. The second output terminal of the microprocessor 23 is connected to the input terminal of the distance display unit 30.

Regarding the correspondence between the present invention and the embodiment, the aiming means 1 corresponds to the drive circuit 24, the laser diode 25 and the lens 26a, and the transmitting means 2 corresponds to the drive circuit 24, the laser diode 25 and the lens 2.
6a, the receiving means 3 corresponds to the lens 26b and the light receiving element 27, and the distance calculating means 4 corresponds to the microprocessor 23 and the phase comparison circuit 29.

FIG. 3 is a flow chart showing the operation of the embodiment. The operation of the embodiment of the present invention will be described below with reference to FIG. When the measurer turns on the switch 22a (step S1), the microprocessor 23 outputs an aiming modulation command to the drive circuit 24 (step S2). When the drive circuit 24 receives the aiming modulation command, it receives 0.5-2H.
The rectangular wave signal of z is output to the laser diode 25, and the laser light generated from the laser diode 25 is 0.5 to 2H.
It is made to blink in the cycle of z (step S3).

The blinking aiming laser light is emitted to the outside through the lens 26a (step S4). However, the wavelength of the aiming laser light is in the visible region. The measurer uses the blinking aiming laser light to aim at the object to be measured. Next, the measurer turns the switch 22
Insert b (step S5). Microprocessor 23
Outputs a measurement modulation command to the drive circuit 24 (step S6).

The drive circuit 24 receives the measurement modulation command and outputs the laser modulation signal to the laser diode 25 and the phase comparison circuit 29. However, the laser modulation signal is a sine wave having a frequency that determines the distance measurement resolution. The drive circuit 24 modulates the laser light generated from the laser diode 25 with a sine wave (step S7).

Instead of the aiming laser light, the measuring laser light modulated by the sine wave is emitted to the outside through the lens 26a (step S8). The measurement laser light reflected from the measurement object and returned from the outside is received by the light receiving element 27 via the lens 26b (step S9). The light receiving element 27 photoelectrically converts the measuring laser light into a light receiving signal.

The received light signal is received by the phase comparison circuit 29 via the amplifier 28. The phase comparison circuit 29 measures the phase difference between the laser modulation signal and the light reception signal. This phase difference is propagation delay time information between the emitted measurement laser light and the received measurement laser light. The phase comparison circuit 29 outputs the measured phase difference to the microprocessor 23,
The microprocessor 23 calculates the distance to the measurement target (step S10).

The microprocessor 23 has a distance display section 30.
Display the measured distance data on. Thus, in the above-mentioned embodiment, the aiming laser light blinks. Therefore, even if the distance is measured outdoors or in a place where the object to be measured is far,
The irradiation spot of the aiming laser light is clarified, and the aiming object can be easily and quickly aimed at.

Further, since blinking laser light is emitted as the aiming laser light, it is possible to reduce power consumption as compared with the case where conventional continuous laser light is emitted. As a result, the battery can be made smaller, and the device itself can be made smaller and lighter. In the above-described embodiment, the laser light is used as the measurement wave, but the measurement wave is not limited thereto. For example, a propagating wave having a reflective property such as an electromagnetic wave or a sound wave can be used as a measuring wave.

Further, in the above-mentioned embodiment, the aiming laser light and the measuring laser light are generated from one laser diode, but the invention is not limited to this.
For example, the aiming laser light and the measuring laser light may be generated from separate laser diodes.

In the above-described embodiment, the distance is measured based on the phase delay of the measuring laser light, but the present invention is not limited to this, and the distance is measured based on the propagation delay time of the measuring laser pulse light. Good. In the above-described embodiment, the aiming laser light is modulated and blinked, but the invention is not limited to this. For example, the aiming laser light may be blinked by providing an opening / closing shutter at the exit of the aiming laser light.

[0024]

In the conventional distance measuring device, continuous light is emitted as aiming light, but in the distance measuring device of the present invention, blinking aiming light is emitted. Therefore, when the aiming light flashes, the irradiation spot of the aiming light becomes clear, and the measurer can easily and quickly aim.

Further, since the blinking aiming light is used in the present invention, it is possible to reduce power consumption as compared with the conventional distance measuring device using continuous laser light. As a result, the battery can be made smaller and the distance measuring device itself can be made smaller and lighter, so that it is possible to provide a portable distance measuring device. In this way, in the distance measuring device to which the present invention is applied, the irradiation spot of the aiming light can be clarified, and the distance can be measured accurately, easily and quickly.

[Brief description of drawings]

FIG. 1 is a principle block diagram of the present invention.

FIG. 2 is a configuration diagram of an embodiment corresponding to the present invention.

FIG. 3 is a flowchart showing the operation of the embodiment.

[Explanation of symbols]

 1 aiming means 2 transmitting means 3 receiving means 4 distance calculating means 21 main body 22a, b switch 23 microprocessor 24 drive circuit 25 laser diode 26a, b lens 27 light receiving element 28 amplifier 29 phase comparison circuit 30 distance display section

Claims (1)

[Claims] 1. A aiming means for emitting aiming light in a predetermined direction, a transmitting means for transmitting a measuring wave in the predetermined direction, a receiving means for receiving a measuring wave returning from the predetermined direction, and a receiving means for receiving in the receiving means. Based on the propagation delay of the measured wave, the distance measuring device comprising a distance calculating means for calculating the distance to the target object located in the predetermined direction, the aiming means, blinking aiming light in the predetermined direction. A distance measuring device characterized by emitting light.