JPH05323029A - Distance measuring method by light wave range finder - Google Patents
Distance measuring method by light wave range finderInfo
- Publication number
- JPH05323029A JPH05323029A JP4125090A JP12509092A JPH05323029A JP H05323029 A JPH05323029 A JP H05323029A JP 4125090 A JP4125090 A JP 4125090A JP 12509092 A JP12509092 A JP 12509092A JP H05323029 A JPH05323029 A JP H05323029A
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- Prior art keywords
- reference signal
- phase difference
- signal
- distance
- light
- Prior art date
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Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、測距光と参照光の位相
差から測点までの距離を測定する光波距離計による測距
方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a distance measuring method using a light wave distance meter for measuring a distance from a phase difference between distance measuring light and reference light to a measuring point.
【０００２】[0002]
【従来の技術】従来、光波距離計においては、図１に示
すように、発振部ａ、周波数選択部ｂ、変調部ｃを経
て、電源の電力を３つの周波数の信号でそれぞれ変調し
て発光素子ｄから３つの変調周波数の光を測距光として
図示しない測点におかれた反射鏡に向けて順次出射し、
反射光で反射された測距光を受光素子ｅで受光して測距
信号に変換し、この測距信号と、前記周波数選択部ｂか
ら出力した測距信号と同一周波数の基準信号を、計数ス
タート信号及び計数ストップ信号として計数器ｆで計数
パルスを計数し、各周波数について測距信号と基準信号
の位相差を得る。次いで、光路切換器ｇを距離計本体内
の参照光路ｈ側に切換えて発光素子ｄから３つの変調周
波数の光を参照光として参照光路ｈに順次出射し、ミラ
ーｉ1、ｉ2を経て参照光を受光素子ｅで受光して参照信
号に変換し、各周波数について参照信号と基準信号の位
相差を測距信号と同様にして得る。各周波数について、
測定された測距信号と基準信号の位相差と、参照信号と
基準信号の位相差との差を図示しない演算回路で求め、
測点までの距離を算出する。2. Description of the Related Art Conventionally, in an optical distance meter, as shown in FIG. 1, an electric power of a power source is respectively modulated by a signal of three frequencies through an oscillating section a, a frequency selecting section b and a modulating section c to emit light. The light of three modulation frequencies is sequentially emitted from the element d as distance measuring light toward a reflecting mirror placed at a measuring point (not shown),
The distance measuring light reflected by the reflected light is received by the light receiving element e and converted into a distance measuring signal, and the distance measuring signal and the reference signal having the same frequency as the distance measuring signal output from the frequency selecting section b are counted. The counting pulse is counted by the counter f as the start signal and the counting stop signal, and the phase difference between the distance measurement signal and the reference signal is obtained for each frequency. Then, the optical path switch g is switched to the side of the reference optical path h in the body of the rangefinder, and the light of the three modulation frequencies is sequentially emitted from the light emitting element d to the reference optical path h as reference light, and is referred to via the mirrors i 1 and i 2 . The light is received by the light receiving element e and converted into a reference signal, and the phase difference between the reference signal and the reference signal for each frequency is obtained in the same manner as the distance measurement signal. For each frequency,
The difference between the phase difference between the measured ranging signal and the reference signal, and the difference between the reference signal and the reference signal is calculated by an arithmetic circuit (not shown),
Calculate the distance to the station.
【０００３】前記３つの周波数は、例えばｆ1＝１５Ｍ
Ｈｚの精測定用周波数と例えばｆ2＝１５０ＫＨｚ、ｆ3
＝１６５ＫＨｚの互いに近接した２つの粗測定用周波数
である。この２つの粗測定用周波数ｆ2、ｆ3により測定
した前記２つの位相差を用いることによりｆ3−ｆ2の周
波数すなわち、遠距離測定用（更なる粗測定用）周波数
により測定しなくても前記２つの位相差の差から測点ま
での更なる粗測距離を求めることができる。The three frequencies are, for example, f 1 = 15M
Hz for precise measurement and, for example, f 2 = 150 KHz, f 3
= 165 KHz, two coarse measurement frequencies close to each other. By using the two phase differences measured by the two coarse measurement frequencies f 2 and f 3 , it is not necessary to measure at the frequency of f 3 −f 2 , that is, the frequency for long distance measurement (for further coarse measurement). Further, it is possible to obtain a further rough measurement distance from the difference between the two phase differences to the measurement point.
【０００４】測点までの距離は、以上のようにして求め
るが、前記測距信号と基準信号の位相差と、参照信号と
基準信号の位相差は通常１回ではなく、多数回例えば数
百回測定され、その平均値が用いられる。The distance to the measuring point is obtained as described above, but the phase difference between the distance measuring signal and the standard signal and the phase difference between the reference signal and the standard signal are usually not once but many times, for example, several hundreds. It is measured twice and the average value is used.
【０００５】[0005]
【発明が解決しようとする課題】従来の光波距離計によ
る測距方法によれば、３つの周波数について、測距信号
と基準信号の位相差と、参照信号と基準信号の位相差の
測定を同一回数例えば数百回行ない、測距データを得て
いたので、測距時間が長いという課題があった。本発明
は、従来の測距方法と同程度の測定精度で測距時間を短
縮することができる光波距離計による測距方法を提供す
ることをその目的とするものである。According to the conventional distance measuring method using the optical distance meter, the phase difference between the distance measuring signal and the reference signal and the phase difference between the reference signal and the reference signal are measured at the same frequency for three frequencies. Since the distance measurement data was obtained by performing the number of times, for example, hundreds of times, there was a problem that the distance measurement time was long. An object of the present invention is to provide a distance measuring method using a light wave distance meter, which can reduce the distance measuring time with the same measurement accuracy as that of the conventional distance measuring method.
【０００６】[0006]
【課題を解決するための手段】上記の目的を達成するた
めに、複数の周波数の変調光を、測距光として測点に置
かれた反射鏡に向けて発光素子から順次出射し、該反射
鏡で反射してきた測距光を受光素子で測距信号に変換
し、一方、前記複数の周波数の変調光を、参照光として
距離計本体内部の参照光路に発光素子から順次出射し、
該参照光を受光素子で参照信号に変換し、各周波数にお
ける前記測距信号と基準信号の位相差及び参照信号と基
準信号の位相差を多数回測定して各位相差の平均値を算
出し、各周波数における前記測距信号と基準信号の平均
位相差と前記参照信号と基準信号の平均位相差との差か
ら測点までの距離を測定する光波距離計による測距方法
において、請求項１記載の発明は、参照信号と基準信号
の位相差の測定回数を、測距信号と基準信号の位相差の
測定回数より少なくしたことを特徴とし、請求項２記載
の発明は、測距信号と基準信号の位相差の測定回数及び
参照信号と基準信号の位相差の測定回数を、低い変調周
波数程少なくしたことを特徴とし、請求項３記載の発明
は、参照信号と基準信号の位相差の測定回数を、測距信
号と基準信号の位相差の測定回数より少なくし、且つ測
距信号と基準信号の位相差の測定回数を、低い周波数程
少なくしたことを特徴とする。In order to achieve the above object, modulated light of a plurality of frequencies is sequentially emitted from a light emitting element toward a reflecting mirror placed at a measuring point as distance measuring light, and the reflected light is reflected. The distance measuring light reflected by the mirror is converted into a distance measuring signal by the light receiving element, while the modulated light of the plurality of frequencies is sequentially emitted from the light emitting element to the reference optical path inside the rangefinder body as reference light,
The reference light is converted into a reference signal by a light receiving element, the phase difference between the ranging signal and the reference signal at each frequency and the phase difference between the reference signal and the reference signal are measured many times to calculate the average value of each phase difference, The distance measuring method using an optical distance meter for measuring a distance to a measuring point from a difference between an average phase difference between the distance measuring signal and the reference signal and an average phase difference between the reference signal and the reference signal at each frequency. The invention according to claim 2 is characterized in that the number of times of measuring the phase difference between the reference signal and the reference signal is made smaller than the number of times of measuring the phase difference between the distance measuring signal and the standard signal. The number of measurements of the phase difference between the signals and the number of measurements of the phase difference between the reference signal and the reference signal are reduced as the modulation frequency decreases, and the invention according to claim 3 measures the phase difference between the reference signal and the reference signal. The number of times the distance measurement signal and reference signal Less than the number of measurements of the difference, and the number of measurements of the phase difference of the distance measurement signal and the reference signal, characterized in that less as low frequencies.
【０００７】[0007]
【作用】距離計本体内部の参照光路を通過する参照光は
安定している。したがって、参照信号と基準信号の位相
差の測定回数が、測距信号と基準信号の位相差の測定回
数より少なくても測定誤差につながらず、測定回数の少
ない分だけ従来の方法より測距時間を短縮することがで
きる。また、例えば３つの周波数のうち、粗測定用周波
数すなわち低い変調周波数については、例えば８桁の測
定データの上２桁にしか用いられないから、例えば４桁
に用いられる精測定用周波数すなわち高い変調周波数に
比べて測距信号と基準信号の位相差の測定回数を少なく
しても測定誤差につながらない。したがって従来の方法
に比べて測定回数の少ない分だけ測距時間を短縮するこ
とができる。Function The reference light passing through the reference light path inside the rangefinder main body is stable. Therefore, even if the number of measurements of the phase difference between the reference signal and the reference signal is less than the number of measurements of the phase difference between the ranging signal and the reference signal, it does not lead to a measurement error. Can be shortened. Further, of the three frequencies, for example, the coarse measurement frequency, that is, the low modulation frequency is used only in the upper two digits of the 8-digit measurement data, so that the precise measurement frequency, that is, the high modulation frequency used in the 4-digit, for example, is used. Even if the number of times of measuring the phase difference between the distance measurement signal and the reference signal is smaller than that of the frequency, no measurement error occurs. Therefore, compared with the conventional method, the distance measurement time can be shortened by the smaller number of measurements.
【０００８】参照信号と基準信号の位相差の測定回数
を、測距信号と基準信号の位相差の測定回数よりも少な
くし、且つ測距信号と基準信号の位相差の測定回数を低
い周波数程少なくすれば、従来の方法より更に一層測距
時間を短縮することができる。The number of measurements of the phase difference between the reference signal and the reference signal is made smaller than the number of measurements of the phase difference between the distance measurement signal and the reference signal, and the frequency of measurement of the phase difference between the distance measurement signal and the reference signal becomes lower. If the number is reduced, the distance measurement time can be further shortened as compared with the conventional method.
【０００９】[0009]
【実施例】例えば３つの変調周波数を、従来例と同様
に、ｆ1＝１５ＭＨｚ、ｆ2＝１５０ＫＨｚ、ｆ3＝１６
５ＫＨｚとして、光波距離計から例えば１２３４．５６
７ｍの距離にある測点を測距すると、周波数ｆ1では
４．５６７ｍ、周波数ｆ2では、２３４．５６ｍ、周波
数ｆ3−ｆ2では１２３４ｍであり、精測距用周波数によ
る測定データを優先し、各周波数による測定データを組
合せると、１２３４．５６７ｍの測距値が得られる。EXAMPLE For example, three modulation frequencies are f 1 = 15 MHz, f 2 = 150 KHz, f 3 = 16 as in the conventional example.
Assuming that the frequency is 5 KHz, from an optical distance meter, for example, 1234.56.
When measuring a measuring point at a distance of 7 m, the frequency f 1 is 4.567 m, the frequency f 2 is 234.56 m, and the frequency f 3 −f 2 is 1234 m. Then, by combining the measurement data at each frequency, a distance measurement value of 1234.567 m is obtained.
【００１０】精密測定の場合には、周波数ｆ1による測
距信号と基準信号の位相差の測定及び参照信号と基準信
号の位相差の測定は、それぞれ１０，０００回及び５０
００回行ない、周波数ｆ2による測距信号と基準信号の
位相差の測定及び参照信号と基準信号の位相差の測定
は、周波数ｆ1による場合より少ない回数すなわち２５
００回行ない、周波数ｆ3による測距信号と基準信号の
位相差の測定及び参照信号と基準信号の位相差の測定は
それぞれ１０００回行なった。この場合、データ出力
は、７桁で、１ｍｍまで安定して表示可能である。In the case of precision measurement, the phase difference between the ranging signal and the reference signal at the frequency f 1 and the phase difference between the reference signal and the reference signal are measured 10,000 times and 50 times, respectively.
00 times performed, measurement of the phase difference between the measurement and the reference signal and the reference signal of the phase difference between the measuring signal and the reference signal by the frequency f 2 is the number of times i.e. 25 less than with the frequency f 1
The measurement was performed 00 times, and the measurement of the phase difference between the distance measurement signal and the reference signal at the frequency f 3 and the measurement of the phase difference between the reference signal and the reference signal were performed 1000 times. In this case, the data output is 7 digits and can be stably displayed up to 1 mm.
【００１１】それほど精度の要求されない簡易測定の場
合には、周波数ｆ1による測距信号と基準信号の位相差
の測定及び参照信号と基準信号の位相差の測定はそれぞ
れ５０００回及び２５００回行ない、周波数ｆ2及びｆ3
による測距信号と基準信号の位相差の測定及び参照信号
と基準信号の位相差の測定はそれぞれ１０００回行なっ
た。この場合、データ出力は７桁であるが、１ｍｍまで
表示可能である。In the case of the simple measurement which does not require so high accuracy, the measurement of the phase difference between the ranging signal and the reference signal and the measurement of the phase difference between the reference signal and the reference signal at frequency f 1 are performed 5000 times and 2500 times, respectively. Frequencies f 2 and f 3
The measurement of the phase difference between the distance measurement signal and the reference signal and the measurement of the phase difference between the reference signal and the reference signal were each performed 1000 times. In this case, the data output is 7 digits, but can be displayed up to 1 mm.
【００１２】[0012]
【発明の効果】請求項１乃至３に記載の発明によれば、
従来の光波距離計による測距方法と同程度の測定精度で
測距時間を短縮することができる効果を有する。According to the invention described in claims 1 to 3,
The distance measuring time can be shortened with the same measurement accuracy as that of the conventional distance measuring method using a light wave distance meter.
【図１】 光波距離計の概略構成を示す線図FIG. 1 is a diagram showing a schematic configuration of a lightwave rangefinder.
ａ 発振部 ｂ 周波数選択部 ｃ 変調部 ｄ 発光部 ｅ 受光部 ｆ 計数器 ｇ 光路切換器 ｈ 参照光路 ｉ1、ｉ2 ミラーa oscillator section b frequency selection section c modulation section d light emitting section e light receiving section f counter g optical path switcher h reference optical path i 1 , i 2 mirror
Claims (3)
測点に置かれた反射鏡に向けて発光素子から順次出射
し、該反射鏡で反射してきた測距光を受光素子で測距信
号に変換し、一方、前記複数の周波数の変調光を、参照
光として距離計本体内部の参照光路に発光素子から順次
出射し、該参照光を受光素子で参照信号に変換し、各周
波数における前記測距信号と基準信号の位相差及び参照
信号と基準信号の位相差を多数回測定して各位相差の平
均値を算出し、各周波数における前記測距信号と基準信
号の平均位相差と前記参照信号と基準信号の平均位相差
との差から測点までの距離を測定する光波距離計による
測距方法において、参照信号と基準信号の位相差の測定
回数を、測距信号と基準信号の位相差の測定回数より少
なくしたことを特徴とする光波距離計による測距方法。1. A modulated light having a plurality of frequencies is sequentially emitted from a light emitting element as a distance measuring light toward a reflecting mirror placed at a measuring point, and the distance measuring light reflected by the reflecting mirror is measured by a light receiving element. Converted to a distance signal, on the other hand, the modulated light of the plurality of frequencies is sequentially emitted as a reference light to the reference optical path inside the rangefinder main body from the light emitting element, and the reference light is converted to a reference signal by the light receiving element, and each frequency is converted. In the phase difference between the distance measurement signal and the reference signal and the reference signal and the phase difference between the reference signal is measured many times to calculate the average value of each phase difference, and the average phase difference between the distance measurement signal and the reference signal at each frequency and In the distance measuring method by the light wave distance meter for measuring the distance from the difference between the reference signal and the average phase difference of the reference signal to the measuring point, the number of times of measurement of the phase difference between the reference signal and the reference signal, the distance measuring signal and the reference signal It is characterized in that it is less than the number of measurements of the phase difference of Distance measurement method using a lightwave rangefinder.
測点に置かれた反射鏡に向けて発光素子から順次出射
し、該反射鏡で反射してきた測距光を受光素子で測距信
号に変換し、一方、前記複数の周波数の変調光を、参照
光として距離計本体内部の参照光路に発光素子から順次
出射し、該参照光を受光素子で参照信号に変換し、各周
波数における前記測距信号と基準信号の位相差及び参照
信号と基準信号の位相差を多数回測定して各位相差の平
均値を算出し、各周波数における前記測距信号と基準信
号の平均位相差と前記参照信号と基準信号の平均位相差
との差から測点までの距離を測定する光波距離計による
測距方法において、測距信号と基準信号の位相差の測定
回数及び参照信号と基準信号の位相差の測定回数を、低
い変調周波数程少なくしたことを特徴とする光波距離計
による測距方法。2. Modulated light of a plurality of frequencies is sequentially emitted from a light emitting element toward a reflecting mirror placed at a measuring point as distance measuring light, and the distance measuring light reflected by the reflecting mirror is measured by a light receiving element. Converted to a distance signal, on the other hand, the modulated light of the plurality of frequencies is sequentially emitted as a reference light to the reference optical path inside the rangefinder main body from the light emitting element, and the reference light is converted to a reference signal by the light receiving element, and each frequency is converted. In the phase difference between the distance measurement signal and the reference signal and the reference signal and the phase difference between the reference signal is measured many times to calculate the average value of each phase difference, and the average phase difference between the distance measurement signal and the reference signal at each frequency and In the distance measuring method by the light wave distance meter for measuring the distance from the difference between the reference signal and the average phase difference of the reference signal to the measuring point, the number of times of measuring the phase difference between the distance measuring signal and the reference signal and the reference signal and the reference signal Fewer phase difference measurements, lower modulation frequencies A distance measuring method using a light wave distance meter characterized by the above.
測点に置かれた反射鏡に向けて発光素子から順次出射
し、該反射鏡で反射してきた測距光を受光素子で測距信
号に変換し、一方、前記複数の周波数の変調光を、参照
光として距離計本体内部の参照光路に発光素子から順次
出射し、該参照光を受光素子で参照信号に変換し、各周
波数における前記測距信号と基準信号の位相差及び参照
信号と基準信号の位相差を多数回測定して各位相差の平
均値を算出し、各周波数における前記測距信号と基準信
号の平均位相差と前記参照信号と基準信号の平均位相差
との差から測点までの距離を測定する光波距離計による
測距方法において、参照信号と基準信号の位相差の測定
回数を、測距信号と基準信号の位相差の測定回数より少
なくし、且つ測距信号と基準信号の位相差の測定回数
を、低い周波数程少なくしたことを特徴とする光波距離
計による測距方法。3. Modulated light of a plurality of frequencies is sequentially emitted from a light emitting element as a distance measuring light toward a reflecting mirror placed at a measuring point, and the distance measuring light reflected by the reflecting mirror is measured by a light receiving element. Converted to a distance signal, on the other hand, the modulated light of the plurality of frequencies is sequentially emitted as a reference light to the reference optical path inside the rangefinder main body from the light emitting element, and the reference light is converted to a reference signal by the light receiving element, and each frequency is converted. In the phase difference between the distance measurement signal and the reference signal and the reference signal and the phase difference between the reference signal is measured many times to calculate the average value of each phase difference, and the average phase difference between the distance measurement signal and the reference signal at each frequency and In the distance measuring method by the light wave distance meter for measuring the distance from the difference between the reference signal and the average phase difference of the reference signal to the measuring point, the number of times of measurement of the phase difference between the reference signal and the reference signal, the distance measuring signal and the reference signal Less than the number of phase difference measurements, and the distance measurement signal And the reference signal phase difference is measured less frequently at lower frequencies.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4125090A JPH05323029A (en) | 1992-05-18 | 1992-05-18 | Distance measuring method by light wave range finder |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4125090A JPH05323029A (en) | 1992-05-18 | 1992-05-18 | Distance measuring method by light wave range finder |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH05323029A true JPH05323029A (en) | 1993-12-07 |
Family
ID=14901600
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP4125090A Pending JPH05323029A (en) | 1992-05-18 | 1992-05-18 | Distance measuring method by light wave range finder |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH05323029A (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010014502A (en) * | 2008-07-02 | 2010-01-21 | Murata Mach Ltd | Optical range finder |
| JP2010286240A (en) * | 2009-06-09 | 2010-12-24 | Sokkia Topcon Co Ltd | Light wave range finder |
| JP2011013068A (en) * | 2009-07-01 | 2011-01-20 | Sokkia Topcon Co Ltd | Lightwave distance meter |
| JP2011257285A (en) * | 2010-06-10 | 2011-12-22 | Kyosan Electric Mfg Co Ltd | Distance sensor and control method |
| JP2012002559A (en) * | 2010-06-15 | 2012-01-05 | Kyosan Electric Mfg Co Ltd | Distance sensor |
| JP2012202944A (en) * | 2011-03-28 | 2012-10-22 | Topcon Corp | Light wave distance meter |
| JP2013003025A (en) * | 2011-06-20 | 2013-01-07 | Mitsubishi Electric Corp | Laser distance measuring device |
-
1992
- 1992-05-18 JP JP4125090A patent/JPH05323029A/en active Pending
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010014502A (en) * | 2008-07-02 | 2010-01-21 | Murata Mach Ltd | Optical range finder |
| JP2010286240A (en) * | 2009-06-09 | 2010-12-24 | Sokkia Topcon Co Ltd | Light wave range finder |
| JP2011013068A (en) * | 2009-07-01 | 2011-01-20 | Sokkia Topcon Co Ltd | Lightwave distance meter |
| JP2011257285A (en) * | 2010-06-10 | 2011-12-22 | Kyosan Electric Mfg Co Ltd | Distance sensor and control method |
| JP2012002559A (en) * | 2010-06-15 | 2012-01-05 | Kyosan Electric Mfg Co Ltd | Distance sensor |
| JP2012202944A (en) * | 2011-03-28 | 2012-10-22 | Topcon Corp | Light wave distance meter |
| JP2013003025A (en) * | 2011-06-20 | 2013-01-07 | Mitsubishi Electric Corp | Laser distance measuring device |
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