JP2004333398A - Laser distance measuring device and calibration method for the laser distance meter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To calibrate errors caused in distance data, based on the color and gloss of an object to be measured, when distance is measured using a laser distance meter. <P>SOLUTION: The laser distance measuring device is constituted, by providing a standard reflector S of a reference color and reference glossiness on the surface of the object to be measured T, measuring the distance to the object T by a laser distance meter 1, removing the standard reflector S from the object, and measuring the distance twice. When a difference over the thickness (a) of the standard reflector S is produced, calibration is conducted by setting the difference as a deviation. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
[Industrial applications]
The present invention relates to an apparatus and a calibration method for optically measuring a distance using a laser range finder, and more particularly, to a method for reducing a measurement error based on the color and gloss of the surface of an object to be measured.
[0002]
[Prior art]
Laser rangefinders are relatively expensive, but are becoming popular because they are easy to handle and can measure accurately as long as they are line of sight.
[0003]
As the laser range finder 4, which is sold under the name "laser distance sensor LDS-1" from the Swiss Leica Geosystems Inc. of module "DISTO pro 4 ^a" Murakami Giken industry that incorporates.
[0004]
This laser range finder has, as output data, "distance data" indicating a distance to a target, "reflection intensity data" indicating the intensity of a reflected light beam received, and the like, and any one of the data is output by a command. The mode can be selected.
[0005]
[Problems to be solved by the invention]
When the distance to the object to be measured is measured by such a conventional laser distance meter, errors may occur in the distance data measured due to the color and gloss of the surface of the object to be measured, and the errors are caused by the distance and the distance. It became clear that it was almost constant regardless of the angle between the optical axis and the surface of the measurement object.
[0006]
Therefore, the present invention has been conceived to correct an error in distance data generated based on the color and gloss of a measured object when a distance is measured using a laser distance meter.
[0007]
[Means for Solving the Problems]
A laser distance measuring device provided with the calibration means of the present invention includes a distance indicator for displaying distance data output from the laser distance meter, a numerical data generator, and the numerical data to the distance data output from the laser distance meter. Providing an adder / subtractor for adding / subtracting numerical data output from the generator, providing a standard reflector of a reference color / reference gloss on the surface of the measured object, measuring the distance to the measured object by the laser distance meter, The standard reflector is removed from the object to be measured, and the distance is measured again. When a difference of two times or more in the distance data is greater than the thickness of the standard reflector, the difference is represented by the numerical data generator. Is set to
[0008]
The calibration method of the laser range finder of the present invention includes the steps of: providing a standard reflector having a reference color and a standard gloss on the surface of the object to be measured; measuring a distance to the object to be measured by the laser range finder; In this method, the reflector is removed, the distance is measured again, and when a difference of two times or more in the distance data is greater than the thickness of the standard reflector, the difference is calibrated as a deviation value.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
In the method for calibrating a laser distance meter according to the present invention, as shown in FIG. 1, an adder / subtractor 3 is provided between a laser distance meter 1 and a distance indicator 2 for displaying distance data output from the laser distance meter 1. Is provided. A numerical data generator 4 such as a dip switch or a digital switch is provided, and an output of the numerical data generator 4 is added to or subtracted from distance data by an adder / subtractor 3.
[0010]
As shown in FIG. 1, the calibration method of the laser range finder of the present invention uses a standard reflector S of a reference color and a reference gloss for reflecting a laser beam B emitted from the laser range finder.
[0011]
At the time of shipment from the factory, the distance to the standard reflector S of the reference color and the reference gloss is measured by the laser distance meter 1, and the measured value is compared with the obtained measurement data to calibrate.
[0012]
At the measurement site, the numerical data generator 4 is set to zero, the laser distance meter 1 is operated, and the standard reflector S is provided on the surface of the measured object T to measure the distance. Next, the standard reflector S is removed from the measured object T, and the distance is measured. As described above, if there is no difference in the distance data obtained by the two measurements that is equal to or more than the thickness of the standard reflector S, it is determined that the measured object T has optically similar reflection characteristics to the standard reflector. The measurement operation may be continued without using the standard reflector S.
[0013]
If the distance display between the case where the standard reflector S is provided on the surface of the measured object T and the case where the standard reflector S is removed from the measured object T is different by at least the thickness a of the standard reflector S, The difference amount is set as an error in the numerical data generator 4, and the distance data measured without using the standard reflector S is added to or subtracted from the error set in the numerical data generator 4 for calibration. Is displayed on the distance display 2.
[0014]
In the embodiment described above, the error is manually input by using the numerical data generator 4. However, when the standard reflector S is provided on the surface of the measured object T using a microcomputer. It is also possible to automatically obtain an error between the case where the standard reflector S is removed and the case where the standard reflector S is removed, and to automatically calibrate the error based on the obtained error.
[0015]
The measurement applying the calibration of the laser range finder described above is, for example, a floor material, measurement of the dimensions of a room for laying tatami mats, measurement of the shape of the inner and outer walls, or measurement for calculating the area It can be used in a field where the color and gloss of the surface of an object to be measured are various, and the accuracy of measurement can be improved.
[0016]
【The invention's effect】
As is clear from the description based on the above embodiment, according to the calibration method of the laser distance meter of the present invention, it is possible to correct the error of the distance data generated based on the color and gloss of the measured object, and to perform the distance measurement. Accuracy can be improved.
[Brief description of the drawings]
FIG. 1 is a block diagram showing an embodiment of a distance / azimuth measuring device used in a method of calibrating a room laser range finder according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Laser range finder 2 Distance indicator 3 Adder / subtractor 4 Numerical data generator T Object to be measured S Standard reflector

Claims (2)

A laser distance meter, a distance indicator for displaying distance data output from the laser distance meter, a numerical data generator, and numerical data output from the numerical data generator to the distance data output from the laser distance meter Is provided with an adder / subtractor for adding and subtracting
Provide a standard reflector of reference color and gloss on the surface of the object to be measured, measure the distance to the object to be measured by the laser distance meter, remove the standard reflector from the object to be measured, and measure the distance again. 2. A laser distance measuring device, comprising: a calibration means for setting a difference amount in the numerical data generator when a difference of not less than the thickness of the standard reflector occurs in the distance data obtained by the twice measurement. apparatus. Provide a standard reflector of reference color and gloss on the surface of the measured object, measure the distance to the measured object with a laser distance meter, remove the standard reflector from the measured object and measure the distance again, A method for calibrating a laser range finder, comprising: when a difference in the distance data obtained by two measurements is equal to or greater than the thickness of the standard reflector, correcting the difference as a deviation value.

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