JPH074959A - Staff for electronic level and electronic level - Google Patents

Abstract

PURPOSE:To eliminate a need for the operation of a mutual correlation or the like and to shorten the measuring time of the electronic level by a method wherein a first pattern and a second pattern whose pattern width cycle is different as well as, according to circumstances, a third pattern in an equal pattern width are arranged at equal intervals in a length-measuring direction. CONSTITUTION:An objective lens part 11 forms the pattern image of a staff for an electronic level, and a compensator 12 forms an image by performing an automatic compensation to make a collimation axis automatically horizontal even when the optical axis of the electronic level 1 is tilted a little. A beam splitter 13 divides light into the direction of the objective lens part 14 and the direction of a linear sensor 15. The linear sensor 15 corresponds to a pattern detection part, it changes the pattern image of the staff for the electronic level, which has been formed by the objective lens part 11 into an electric signal, and it inputs the electric signal to an operation and processing means 16. Then, a first pattern and a second pattern as well as a third pattern, according to circumstances, are arranged sequentially at equal intervals in a length-measuring direction, the first and second patterns are formed in such a way that their pattern width is at mutually different cycles, and the third pattern is formed in an equal pattern width.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic level and an electronic level gauge used for the electronic level, and more particularly to an electronic level for electronically calculating a height difference.

[0002]

2. Description of the Related Art Conventionally, when directly performing leveling or the like, a level (standard level) and a staff are used. That is,
The surveyor measured the height difference by visually observing the scale of the staff using the level. In this classical level survey, there was a reading error by the surveyor. In order to eliminate this misreading, an electronic level has been developed that electronically performs the graduation work of the staff. This electronic level emits light including a predetermined signal from the staff,
This light is received on the electronic level side for identification, and the scale of the staff is read.

[0003]

However, nowadays when the image processing technology has advanced, it is possible to electronically read the scale of the staff by image-processing the scale of the staff whose magnification changes according to the distance. However, there is a problem that it requires a huge amount of processing time and is not practical.
Therefore, even if the scale of the staff on the scale changes according to the distance, it has been strongly desired to provide an electronic level at which the scale of the staff can be electronically read by simple signal processing.

[0004]

The present invention has been devised in view of the above problems, and measures the first pattern, the second pattern, and in some cases the third pattern, which are sequentially arranged at equal intervals. In the direction, the first pattern and the second pattern are formed with pattern widths of different periods, and the third pattern is formed with an equal pattern width.

Further, the electronic level of the present invention is an electronic level which is measured using the above-mentioned electronic level staff, and is for reading the first pattern, the second pattern, and in some cases the third pattern. Pattern detecting section, a reference signal forming section for forming a reference signal from the detection signal detected by the pattern detecting section, a reference signal formed by the reference signal forming section and the pattern detecting section. From the detection signal, a pattern signal forming unit for forming the first pattern signal and the second pattern signal, and the height difference is calculated from the phases of the first pattern signal and the second pattern signal near the collimation line. And a calculation unit for

Further, the electronic level according to the present invention is used for forming a reference signal from a pattern detecting section for reading the first pattern and the second pattern and an interval between detection signals detected by the pattern detecting section. From the reference signal forming unit, the distance measuring unit that measures the distance to the electronic level rod based on the reference signal, the reference signal formed by the reference signal forming unit and the detection signal detected by the pattern detecting unit. , The pattern signal forming unit for forming the first pattern signal and the second pattern signal, and the pattern widths of the first pattern signal and the second pattern signal near the line of sight include the line of sight. It is composed of a block detection unit for specifying the block portion of the pattern and a calculation unit for calculating the height difference based on the specified block.

In the electronic level according to the present invention, when the distance to the electronic level staff is less than a certain distance, the height difference is calculated based on the specified block, and the distance to the electronic level staff is calculated. When the distance is equal to or more than a certain distance, it is possible to include a calculation unit that calculates the height difference from the phases of the first pattern signal and the second pattern signal near the collimation line.

[0008]

According to the present invention constructed as described above, the first pattern, the second pattern, and in some cases, the third pattern are sequentially arranged at equal intervals in the length-measuring direction.
Pattern is formed with a pattern width of a cycle different from each other, and the third pattern is formed with an equal pattern width.

The electronic level of the present invention is an electronic level which is measured by using the above-mentioned electronic level staff, and the pattern detecting section includes a first pattern, a second pattern and a third pattern.
The pattern signal forming unit forms a reference signal from the detection signal detected by the pattern detecting unit, and the pattern signal forming unit detects the reference signal formed by the reference signal forming unit and the pattern detecting unit. From the detected signal
The first pattern signal and the second pattern signal are formed, and the calculating unit calculates the height difference from the phases of the first pattern signal and the second pattern signal near the collimation line.

Further, in the electronic level of the present invention, the reference signal forming unit forms the reference signal from the pulse width of the detection signal detected by the pattern detecting unit, and the block detecting unit outputs the first pattern near the collimation line. From the pattern width of the signal and the pattern width of the second pattern signal, the block portion of the pattern including the line of sight is specified, and the calculation unit calculates the height difference based on the specified block.

In the electronic level of the present invention, the calculation unit
If the distance to the electronic level staff is less than a certain distance, the height difference is calculated based on the specified block, and if the distance to the electronic level staff is more than a certain distance, near the collimation line. It is also possible to calculate the height difference from the phases of the first pattern signal and the second pattern signal.

[0012]

【Example】

An embodiment of the present invention will be described with reference to the drawings.

As shown in FIGS. 1 to 3, the surveying instrument of this embodiment comprises an electronic level 1 and an electronic level staff 2. The electronic level 1 is the leveling device 10 as shown in FIG.
0, as shown in FIG. 1, the objective lens unit 11, the compensator 12, and the beam splitter 13
The eyepiece lens unit 14, the linear sensor 15, and the arithmetic processing unit 16.

The objective lens section 11 is an electronic level staff 2
For forming an image of the pattern. The compensator 12 is an automatic compensation mechanism for automatically leveling the collimation line even if the optical axis of the electronic level 1 is slightly inclined,
The horizontal ray is changed vertically to form an image. The beam splitter 13 directs light to the eyepiece lens unit 14 direction,
It is for dividing in the direction of the linear sensor 15.
The eyepiece portion 14 is used by a surveyor to visually check the electronic level staff 2. The linear sensor 15 corresponds to a pattern detection unit and is for converting the pattern image of the electronic level rod 2 formed by the objective lens unit into an electric signal. In this embodiment, a CCD linear sensor is used. As the linear sensor 15, any sensor can be adopted as long as it is a linear image sensor in which photodiodes are arranged in at least one dimension.

The arithmetic processing means 16 includes an amplifier 161, a sample hold 162, an A / D converter 163, and an RA.
It is composed of an M164, a clock driver 165, a microcomputer 166, and a display 167.

Next, in the electronic level staff 2, as shown in FIG. 2, a first pattern A, a second pattern B, and a third pattern R are repeatedly arranged at equal intervals (p). That is, each block is continuously formed with three types of patterns as one set, and the block arranged on the leftmost side is set to 0
If defined as a block and described as R (0), A (0), B (0), R (1), A (1), B (1), R (2),
A (2), B (2), ... Are repeatedly arranged. Since all patterns are repeated at equal intervals p, the signal corresponding to this interval is used as the reference signal.

In this embodiment, the interval is set to 10 mm, but any interval distance can be adopted. The third pattern R has a black width of 8 mm and a fixed width.
The first pattern A modulates the width of the black portion so that one cycle is 600 mm, and the second pattern B is 570.
The width of the black portion is modulated so that one period is in mm. The first pattern A and the second pattern B can adopt any cycle as long as the cycle is slightly different.
The modulation state of the first pattern A and the second pattern B is as shown in FIG.

The measuring principle of the surveying instrument thus constructed will be described.

First, the principle of obtaining the horizontal position of the electronic level staff 2 will be described.

First pattern A of the electronic level staff 2
, The width of the black portion is modulated so that one cycle is 600 mm. Therefore, if the modulation width is 0 to 10 mm, the width D _A of the first pattern is given by the following equation.

D _A = 5 * (1 + SIN (2 * π * X / 600−π / 2)) ... Formula 1

It becomes However, X = (10 mm, 40 m
m, 70 mm ...

Similarly, since the second pattern B of the electronic level staff 2 modulates the width of the black portion so that one period is 570 mm, the width D _B of the second pattern is as follows. Given by the formula.

D _B = 5 * (1 + SIN (2 * π * X / 570 + π / 2)) Second formula

[0025] However, X = (20mm, 50m
m, 80 mm ...

An offset of ± π / 2 is added in the first and second equations, which is the first in the signal processing.
This is because it is easy to separate the signal according to the pattern A and the signal according to the second pattern B.

Since the first pattern A and the second pattern B have slightly different periods, similar patterns appear at the distance which is the least common multiple of them. In this embodiment, 1140, which is the least common multiple of 600 mm and 570 mm.
A similar pattern appears at 0 mm. Therefore, the phase difference between the signal according to the first pattern A and the signal according to the second pattern B changes from 0 to 2π in the range of 0 to 11400 mm.

That is, the first pattern A in the horizontal position
Assuming that the phase of the signal by Φ _A is the phase of the signal by the second pattern B at the horizontal position is Φ _B , the horizontal position H on the electronic level staff 2 is

H = 11400 * ((φ _B −φ _A −π) / (2π)) mm ...

It becomes

Next, the electronic level 1 and the electronic level staff 2
A method of calculating the distance between and will be described.

When the electronic level staff 2 is read at the electronic level 1 and subjected to Fourier transform, as shown in the power spectrum of FIG. 4, the periodic component of the first pattern A and the second
Of the pattern B, the third pattern R, the first pattern A, and the second pattern B as one set (one block) of the cycle component (three times the cycle of the reference signal) Signal (corresponding to the equally spaced pitch (p) of the pattern)
And the periodic component of The spectrum group moves to the lower frequency side when the distance between the electronic level 1 and the electronic level rod 2 decreases. The reference signal (corresponding to the equally-spaced pitch (p) of the pattern) has the smallest period in the spectrum group. This equal pitch is p
Therefore, the distance between the electronic level 1 and the electronic level rod 2 can be calculated by the image formation formula of the lens.

That is, as shown in FIG. 5, the electronic level rod 2
An evenly spaced pitch p of the image w
Therefore, if the distance from the lens to the electronic level staff 2 is L and the distance from the lens to the image is d,

Since L = d (p / w) and d≈f (f is the focal length of the lens)

L = d (p / w) ≈f (p / w)

It becomes Further, if the image w by the lens of the electronic level 1 is C, the length of one pixel of the linear sensor 15 is C, and one wavelength of the frequency (cycle) corresponding to the equally-spaced pitch p obtained by the linear sensor 15 is k. , W = Ck. Therefore, the distance L between the electronic level 1 and the electronic level staff 2 is

L = ((f / C * k)) * (p) (4th formula)

Therefore, the approximate distance between the electronic level 1 and the electronic level rod 2 can be obtained.

Next, the principle of measuring the high level will be described.

First, the case of long-distance measurement will be described.

As shown in FIG. 6, if the signal obtained by the linear sensor 15 is Fourier-transformed, a signal corresponding to the equal pitch p can be obtained. Here, if the phase obtained by the fast Fourier transform is θ and the phase of the address position (m-th bit) of the linear sensor 15 corresponding to the horizontal position is θ _m ,

H ₁ = (θ _m / 360 °) * p ··· Formula 5

It becomes That is, the horizontal position H ₁ can be accurately measured within the equally-spaced pitch p (fine measurement).

Further, in order to obtain the horizontal position, it is necessary to obtain an approximate position from the pattern start position of the equally-spaced pitch p formed on the electronic level staff 2. Therefore, the output signal of the linear sensor 15 is integrated by the front and rear half pitches of the reference signal (the signal corresponding to the equal pitch p). Further, if the integration value is thinned out every three (product detection), as shown in FIG. 7, the signal 1 corresponding to the first pattern A and the second
The signal 2 corresponding to the pattern B and the signal 3 corresponding to the third pattern R are obtained. However, the third pattern R is not modulated in width and the first pattern A
And the maximum modulation width of the second pattern B is 10 mm,
Since the third pattern R is only 8 mm, the signal 3 corresponding to the third pattern R has a substantially constant integral value, which is about 80% of the value of the signal 1 or the signal 2.

Since the third pattern R, the first pattern A, and the second pattern B are repeatedly arranged in a predetermined order, the thinned signal is the third pattern.
It is possible to determine which one of the pattern R, the first pattern A, and the second pattern B. Further, in order to remove the influence of ambient light such as shading, as shown in FIG. 8, using the signal corresponding to the third pattern R as a reference, (A
-R) and (BR) signals are obtained.

Next, from the signals of (A-R) and (B-R),
R, (A including the reference signal, including the address position (m-th bit) of the linear sensor 15 corresponding to the horizontal position)
-R), a pair of signals of (BR) is selected, and (AR)
And the phase of (BR), the first pattern A, the second pattern B at any position of the electronic level staff 2
It is possible to determine whether the combination is the third pattern R.

Here, the (A-R) signal is set to Am, and (B
-R) signal is Bm, and the maximum amplitude of (A-R) signal is 1
/ 2 is Wa and (BR) is 1/2 of the maximum amplitude of the signal is Wb
Then, the phases of (A−R) and (B−R) are, respectively,

Φ _a = SIN ⁻¹ (Am / Wa) ··· Formula 6

Φ _b = SIN ⁻¹ (Bm / Wb) −2 * π (10/570) ... Formula 7

It becomes The reason for this is that the position of the signal corresponding to the second pattern B is displaced by 10 mm from the signal corresponding to the first pattern A in the fractional part of the seventh expression.

By substituting the sixth and seventh equations into the third equation, the horizontal position of the signal corresponding to the first pattern A on the electronic level rod 2 can be obtained. If the reference signal including the horizontal position belongs to the third pattern R, the horizontal position is reduced by 10 mm, and if the reference signal including the horizontal position belongs to the second pattern B, the horizontal position is 10 mm. Should be added. As a result, an approximate level height H ₂ at the horizontal position can be obtained. (Rough measurement)

As described above, for the level H, the phase of the reference signal at the horizontal position is obtained (fine measurement), and the reference signal corresponding to the horizontal position is based on the pattern start position of the electronic level staff 2. It can be determined by determining from the phase difference between the first pattern A and the second pattern B (coarse measurement) and aligning the precise measurement H ₁ and the coarse measurement H ₂ with each other.

Next, the case of short distance measurement will be described.

In the case of short-distance measurement, the first pattern A, the second pattern B, and the third pattern B are used rather than the Fourier transform as in the long-distance measurement and then the product detection is performed to obtain the standard height. Since a clear image of the pattern R is obtained, higher accuracy can be expected by directly measuring the signal width.

First, as shown in FIG. 9, the output signal is differentiated to obtain the rising and falling edges of the output of the linear sensor 15. From these edges, the interval between the edges of the black portion can be obtained. Further, the bit corresponding to the center of the black portion is obtained. This bit interval is the first
Of the pattern A, the second pattern B, and the third pattern R are equal reference pitches.

Then, when the position of the reference signal before and after the address position (mth bit) corresponding to the horizontal position is obtained, the width of the reference signal corresponds to 10 mm on the electronic level staff 2, and therefore the reference signal before and after the reference signal. _Are respectively N _f (N _{f th} bit) and N _b (N _{b th} bit),

H ₁ = ((m−N _f ) / (N _b −N _f )) * 10 ... Equation 8

It becomes (Precision measurement)

If the starting position of the reference signal is N _e , the final position is N _s , and the number is n, the average of the intervals of each reference signal is

K = (N _e −N _s ) / n

By substituting this k into the fourth equation, the approximate distance between the electronic level 1 and the electronic level rod 2 can be obtained.

Then, the width of the black portion is thinned out every three pieces from the beginning, the third pattern R having a constant width is recognized, and the third pattern R, the first pattern A, and the second pattern B are arranged in this order. Therefore, the correspondence between the third pattern R, the first pattern A, and the second pattern B is determined.

Further, the linear sensor 15 corresponding to the horizontal position
Signal including the address position (m-th bit) of the third pattern R, the first pattern A, the second pattern B
Which of the blocks the user belongs to is determined, and the number of the block to which this corresponds is determined. That is, R (n), A (n),
If it is B (n), it means that it is the nth block.

From the first equation,

D _A = 5 * (1 + SIN (2 * π * Xa /
600-π / 2))

However, Xa = 30 * n + 10

Therefore, n can be obtained from the value of D _A.

Therefore,

N = (10 / π) * (φ _a + (π / 2)) − (1/3) ... Equation 9

Φ _a = SIN ^-1 ((D _A / 5) -1)

It becomes There are two φ _a in the range of 0 to 2π, and only one is selected according to the condition that n is an integer. If this block number is na, there are 600 mm periods (that is, every 20 blocks) on the electronic level staff 2,

N = 20 * d + na

It becomes However, d = 0, 1, 2, 3, ...
・ It is.

Then, using this n, the second pattern B
The width D _B of

X = 30 * n + 20

After substituting into the second equation as, D _B is compared, and when they match, n is the block number to be obtained. Depending on the types of the third pattern R, the first pattern A, and the second pattern B to which the n and m belong, the approximate level height H
₂ (coarse measurement) is

In the case of the third pattern R, H ₂ = 30
* N

In the case of the first pattern A, H ₂ = 30
* N + 10

In the case of the second pattern B, H ₂ = 30
* N + 20

・ ・ ・ Formula 10

It becomes

If not only one set of patterns is judged but also several positions before and after are judged, the error rate due to the contamination of the patterns can be reduced.

Therefore, the reference signal is obtained from the width of the black portion of the signal corresponding to the third pattern R, the first pattern A, and the second pattern B, and the reference signal at the address position corresponding to the horizontal position is determined. The precise measurement is performed by using the phase difference between the signals corresponding to the first pattern A and the second pattern B, and the precision measurement H ₁ and the coarse measurement H ₂ are aligned with each other to obtain a high level. You can ask.

In the above, the modulated first pattern A
The measurement method for distinguishing the pattern signal modulated by using the third pattern R that is not modulated in addition to the second pattern B and the second pattern B has been described. If the signal of the first pattern A and the signal of the second pattern B can be discriminated by determining, for example, then the measurement can be performed without using the third pattern R.

Next, the arithmetic processing means 16 mounted on the electronic level 1 of this embodiment will be described in detail. The amplifier 161 is
The electric signal from the linear sensor 15 is amplified, and the sample and hold 162 samples and holds the amplified electric signal with the timing signal from the clock driver 165. The A / D converter 163 is for A / D converting the sampled and held electric signal. The RAM 164 is for storing the A / D converted digital signal. Further, the microcomputer 166 performs various arithmetic processes.

The function of the microcomputer 166 will be described below with reference to FIG.
6 includes a reference signal forming unit 1661, a pattern signal forming unit 1662, a block detecting unit 1663, and a calculating unit 166.
4, the reference signal forming unit 1661 forms a reference signal corresponding to the equidistant pitch p by the fast Fourier transform from the electric signal obtained from the linear sensor 15 in the case of long distance measurement, and In the case of measurement, the output signal of the area sensor 15 is differentiated and the reference signal is formed from the rising and falling edges.

In the case of long-distance measurement, the pattern signal forming unit 1662 integrates the reference signal in the former and latter half pitches and thins out the integrated value every three (product detection) to obtain the first pattern signal. And the second pattern signal are formed, and in the case of short-distance measurement, the first pattern signal and the second pattern signal are formed by the thinning operation.

[0087] block detection unit 1663, in the case of short distance measurement by comparing the width D _B of the width D _A and the second pattern B of the first pattern A, what number block corresponding to the horizontal position Determine if it is a block.

The calculation unit 1664 calculates the height difference from the phases of the first pattern signal and the second pattern signal in the vicinity of the collimation line in the case of long-distance measurement, and in the case of short-distance measurement, specifies The height difference is calculated based on the selected blocks.

The arithmetic processing means 16 also has a function corresponding to a distance measuring section, and can calculate the horizontal approximate distance between the electronic level 1 and the electronic level staff 2 by calculating the fourth equation. .

The display unit 167 displays the height difference calculated by the calculation unit 1664. A display unit such as a liquid crystal display may be adopted, and the display unit 167 may be configured to output to an external storage unit or the like. .

The operation of this embodiment configured as described above will be described with reference to FIG.

First, step 1 (hereinafter abbreviated as S1)
Then, the electronic level staff 2 is installed at the measured point, the electronic level 1 is activated, and the surveying is started. Next, in S2, the linear sensor 15 captures the images of the third pattern R, the first pattern A, and the second pattern B of the electronic level staff 2 formed by the objective lens unit 11 and converts them into electric signals. To do. Further, in S3, the electric signal taken in from the linear sensor 15 is A / D converted, and in S4, the converted digital signal is stored in the RAM 164. Further, in S5, the electric signal taken in from the linear sensor 15 is subjected to fast Fourier transform (FFT) to perform Fourier transform. FF
Not limited to T, any method such as the maximum entropy method (MEM) can be adopted as long as the method can obtain a spectrum.

Next, in S6, the spectrum group obtained in S5 having the smallest period is selected and used as the reference signal.
Then, in S7, the fourth formula is calculated to calculate the horizontal approximate distance between the electronic level 1 and the electronic level rod 2. In S8, it is determined whether the measurement is a short distance measurement or a long distance measurement based on the calculation result of S7. In this embodiment, the short distance measurement is 10 m or less, but it can be appropriately changed. S
If the determination in 8 is long-distance measurement, the process proceeds to S9 and S
At 9, the output signal of the linear sensor 15 is integrated by the front and rear half pitches of the reference signal. Further, in S10, the integration value is thinned out every three (product detection) to obtain a signal 1 corresponding to the first pattern A, a signal 2 corresponding to the second pattern B, and a third pattern R. The signal 3 corresponding to is extracted. Then, in S11, the integrated value of the signal 3 corresponding to the third pattern R is substantially constant, which is about 80% of the value of the signal 1 and the signal 2, and the order of each pattern is constant. Therefore, it is determined which one of the first pattern A, the second pattern B, and the third pattern R. S1
In 2, the equations 6 and 7 are calculated to find φ _A and φ _B , and S1
Proceeding to 3, the rough measurement H ₂ can be performed by substituting the calculation result of S12 into the third expression.

In step S14, the fifth formula is calculated to make a precise measurement H ₁
After that, the process proceeds to S15, the precision measurement H ₁ and the rough measurement H ₂ are aligned with each other to obtain the level height H, and it is determined whether or not the measurement is completed.

Next, when the determination in S8 is the short distance measurement, the process proceeds to S16, the output signal of the linear sensor 15 is differentiated, and the rising and falling edges are detected. Then S
In step 17, the interval between the edges of the black portion is obtained, and the bit corresponding to the center of the black portion is determined. In S18, a reference signal having a uniform pitch p is formed from the value obtained in S17.

Then, in S19, the eighth formula is calculated to perform the precise measurement H ₁ , and in S20, the width of the black portion is thinned out every three pieces from the beginning, and the third pattern R having a constant width is recognized. Further, in S21, since the order of each pattern is constant, the correspondence between the third pattern R, the first pattern A, and the second pattern B is determined.

Further, in S22, it is determined using the formula 9 or the like which block the reference signal corresponding to the horizontal position corresponds to. In S23, the formula 10 is operated to calculate the rough measurement H.
Do ₂ Then, in S15, the precise measurement H ₁ and the rough measurement H
_The level height H is calculated by aligning the digits of ₂ and it is judged whether or not the measurement is completed. If it is determined in S15 that the measurement has ended, S24
When the measurement is completed in step S15 and the measurement is not completed in step S15, the process returns to step S2.

Then, in S12, the height difference is calculated from the vertical position determined in S11, and the calculated value is displayed on the display 167. Further, in S13, it is determined whether or not the measurement is finished in S13. If the measurement is finished, the process proceeds to S14 and the surveying is finished. If the measurement is not ended in S13, the process returns to S2 and the surveying is repeated.

The calculating unit 1664 may obtain the height difference from the level height H and display it on the display 167.

Next, a second embodiment of the present invention will be described.

In the second embodiment, the respective wavelengths are obtained from the signals corresponding to the detected two types of patterns without using the third pattern R using only the modulated first pattern A and second pattern B. Thus, the signal of the first pattern A and the signal of the second pattern B are discriminated and the measurement is performed.

The electronic level staff 2 of the second embodiment is shown in FIG.
As shown in FIG. 2, the first pattern A and the second pattern B
Are repeatedly arranged at equal intervals (p), and the third pattern R is not arranged, which is different from the electronic level staff 2 of the first embodiment.

Next, the signal processing will be described. Basically, since there are many points in common with the first embodiment, differences will be described.

First, the common point is that the distance between the electronic level 1 and the electronic level rod 2 is calculated based on the reference signal.

In long-distance measurement, precision measurement is the first
Same as the embodiment. In the rough measurement, the output signal of the linear sensor 15 is integrated, and in the signal extraction process of S10 in FIG. Signal 2 corresponding to

In the identification of the obtained signal, at least one cycle is detected because the distance is measured. Therefore, the pattern discrimination unit discriminates a signal having a long cycle as a signal 1 corresponding to the first pattern A and a signal having a short cycle as a signal 2. After determining the signal 1 and the signal 2 in this way, the first
Similar to the embodiment, the respective phases φ _A and φ _B can be obtained, and precision measurement and digit alignment can be performed to obtain the level height. The function of the pattern determination unit is realized by the arithmetic processing means 16.

In the short-distance measurement, since the pattern pitch on the linear sensor 15 of the electronic level 1 corresponds to the width w in the determination of the signal of S21 in FIG. 11, the variation amount of each signal and the reference signal. The signal 1 corresponding to the first pattern A and the signal 2 corresponding to the second pattern B are discriminated based on the pitch width. Specifically, first,
When the cycle of the first pattern is 600 mm and the cycle of the second pattern is 570 mm, the pulse widths of the first and second pulses are the first and second, respectively.
Like the formula,

D _A = 5 * (1 + SIN (2 * π * Xa / 600−π / 2)) Equation 11

It becomes: However, Xa = 20 * n.

D _B = 5 * (1 + SIN (2 * π * Xb / 570 + π / 2)) Equation 12

It becomes: However, Xb = 20 * n + 10.

Incidentally, n is a block number. (N =
0, 1, 2, ...)

On the contrary, the equation for obtaining n from the values of D _A and D _B is obtained by modifying the above equation,

Given D _A ,

N = (15 / π) * (φ _A + π / 2) Equation 13

Φ _A = SIN ^-1 (D _A / 5-1)

Given D _B ,

N = (57 / 4π) * (φ _B −π / 2) − (1/2) Equation 14

Φ _B = SIN ^-1 (D _B / 5-1)

It is expressed as follows.

Then, among the obtained signals, the first pulse width is set to D _A , and n is obtained from the thirteenth expression. In this case, one cycle of 600 mm is sufficient. Two n's are obtained, but n is narrowed down to one depending on whether the second pulse width from the first pulse width is larger or smaller than the first pulse width. Next, the pulse width when n is n + 1 is obtained from the equation 11 and D _{A +
Set} to ₁ . Similarly, when the initial pulse width is D _B , n is obtained and D _{B + 1} is obtained. If the pulse width next to the first pulse width is close to D _{A + 1} , the first pulse width is determined to be the A pattern, and if it is close to D _{B + 1} , the first pulse width is determined to be the B pattern.

After the signal 1 and the signal 2 are discriminated in this way, the block number is determined in the same manner as in the first embodiment, precision measurement and digit alignment are performed, and the level height is obtained.

Next, a modified example will be described.

In the above embodiment, the first and second patterns are formed by the spatial modulation which changes the pattern width.
The present invention is not limited to this, and can be applied even if the pattern density is changed and modulated without changing the pattern width.

[0125]

[Effect] The electronic level staff of the present invention configured as described above has the first pattern and the second pattern, which are sequentially arranged at equal intervals, in the length-measuring direction, and includes the first pattern and the second pattern. The second pattern is formed by being modulated at a cycle different from each other, and the electronic level is detected by the pattern detection unit for reading the first pattern and the second pattern and the pattern detection unit. A first pattern signal and a second pattern signal are generated from a reference signal forming unit for forming a reference signal from the detection signal, and the reference signal formed by the reference signal forming unit and the detection signal detected by the pattern detecting unit. Since the pattern signal forming unit for forming the pattern signal and the calculating unit for calculating the height difference from the phases of the first pattern signal and the second pattern signal in the vicinity of the collimation line are included, Correlation, etc. It is not necessary to perform the operation, there is an effect that the measurement time is reduced.

Furthermore, since the second and third patterns of the electronic level staff are modulated at a constant period, it is not necessary to store and process all the information, and the structure is relatively simple. It has the outstanding effect of being able to achieve electronic level with.

In the electronic level staff of the present invention, a uniform pattern of equal pitch is further added as a third pattern to the first pattern and the second pattern, and these are sequentially arranged at equal intervals. The electronic level of the first pattern can be easily determined by providing a pattern discriminating unit that discriminates between the signal of the first pattern and the signal of the second pattern based on the uniform third pattern signal among the signals extracted from the pattern detecting unit. There is an effect that it is possible to distinguish between the signal and the signal of the second pattern.

[0128]

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of an electronic level 1 according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating an electronic level staff 2 according to the present embodiment.

FIG. 3 is a perspective view showing an appearance of an electronic level 1 according to the present embodiment.

FIG. 4 is a diagram showing a power spectrum of an output signal.

FIG. 5 is a diagram illustrating the principle of distance measurement according to the present embodiment.

FIG. 6 is a diagram illustrating the principle of long-distance measurement according to the present embodiment.

FIG. 7 is a diagram illustrating the principle of long-distance measurement according to the present embodiment.

FIG. 8 is a diagram illustrating the principle of long-distance measurement according to the present embodiment.

FIG. 9 is a diagram illustrating the principle of short-distance measurement according to the present embodiment.

FIG. 10 is a diagram showing a configuration of an arithmetic processing means 16 of the present embodiment.

FIG. 11 is a diagram for explaining the operation of the present embodiment.

FIG. 12 is a diagram showing a pattern of an electronic level staff according to a second embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 electronic level 11 objective lens 12 compensator 13 beam splitter 14 eyepiece part 14 15 linear sensor 16 arithmetic processing means 1661 reference signal forming part 1662 pattern signal forming part 1663 block detecting part 1664 calculating part 2 electronic level standard

[Procedure amendment]

[Submission date] February 22, 1994

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Brief description of the drawing

[Correction method] Change

[Correction content]

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of an electronic level 1 according to an embodiment of the present invention.

FIG. 2 (a) is a diagram illustrating an electronic level staff 2 of the present embodiment.

FIG. 2B is a diagram illustrating an electronic level staff 2 according to the present embodiment.

FIG. 3 is a perspective view showing an appearance of an electronic level 1 according to the present embodiment.

FIG. 4 is a diagram showing a power spectrum of an output signal.

FIG. 5 is a diagram illustrating the principle of distance measurement according to the present embodiment.

FIG. 6 is a diagram illustrating the principle of long-distance measurement according to the present embodiment.

FIG. 7 is a diagram illustrating the principle of long-distance measurement according to the present embodiment.

FIG. 8 is a diagram illustrating the principle of long-distance measurement according to the present embodiment.

FIG. 9 is a diagram illustrating the principle of short-distance measurement according to the present embodiment.

FIG. 10 is a diagram showing a configuration of an arithmetic processing means 16 of the present embodiment.

FIG. 11 is a diagram for explaining the operation of the present embodiment.

FIG. 12 is a diagram showing a pattern of an electronic level staff according to a second embodiment.

[Description of Reference Signs] 1 electronic level 11 objective lens 12 compensator 13 beam splitter 14 eyepiece part 15 linear sensor 16 arithmetic processing means 1661 reference signal forming part 1662 pattern signal forming part 1663 block detecting part 1664 calculating part 2 electronic level staff

[Procedure Amendment 2]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 2

[Correction method] Change

[Correction content]

[Figure 2 (a)]

[Fig. 2 (b)]

Claims (7)

[Claims] 1. A first pattern modulated in a first cycle and a second pattern modulated in a second cycle different from the first cycle, wherein the first pattern and the second pattern are measured. An electronic level staff, which is constructed by arranging in sequence at equal pitches. 2. The electronic level staff according to claim 1, wherein the modulation of the first pattern and the second pattern is performed by spatial modulation for changing a line width. 3. In addition to the first pattern and the second pattern, a uniform third pattern is provided, and the first pattern, the second pattern and the third pattern are sequentially arranged at equal pitches in the length measuring direction. The electronic level staff according to claim 1 or 2, which is configured by: 4. An electronic level that is measured using the electronic level rod according to claim 1, and a pattern detection unit that detects the first pattern and the second pattern,
From the reference signal forming unit that forms a reference signal from the intervals of the detection signals detected by the pattern detecting unit, the reference signal formed by the reference signal forming unit and the detection signal detected by the pattern detecting unit, A pattern signal forming unit that forms a first pattern signal and a second pattern signal, and a calculation unit that calculates a height difference from the phase of the first pattern signal near the collimation line and the phase of the second pattern signal. Electronic level characterized by being. 5. An electronic level that is measured using the electronic level rod according to claim 1, and a pattern detection unit that detects the first pattern and the second pattern,
From the reference signal forming unit that forms a reference signal from the intervals of the detection signals detected by the pattern detecting unit, the reference signal formed by the reference signal forming unit and the detection signal detected by the pattern detecting unit, A pattern signal forming unit that forms the first pattern signal and the second pattern signal, and a block unit of the pattern that includes the collimation line from the modulation component levels of the first pattern signal and the second pattern near the collimation line. An electronic level comprising: a block detection unit that specifies a block; and a calculation unit that calculates a height difference based on the specified block. 6. An electronic level to be measured using the electronic level rod according to claim 1, a pattern detecting section for detecting the first pattern and the second pattern, and detection by the pattern detecting section. A reference signal forming unit that forms a reference signal from the intervals of the detected signals, a distance measuring unit that measures the distance to the electronic level staff based on this reference signal, and a reference signal formed by this reference signal forming unit. A pattern signal forming unit that forms a first pattern signal and a second pattern signal from the detection signal detected by the pattern detecting unit, a reference signal formed by the reference signal forming unit, and the pattern detecting unit. Block detection for identifying the block portion of the pattern including the collimation line from the modulation component levels of the first pattern signal and the second pattern near the collimation line based on the detected detection signal And when the distance to the electronic level staff is a predetermined distance or more, a height difference is calculated from the phases of the first pattern signal and the second pattern signal near the collimation line, and the electronic level staff is calculated. An electronic level comprising: a calculation unit that calculates a height difference based on the specified block when the distance to is less than or equal to a predetermined distance. 7. An electronic level measured using the electronic level rod according to claim 3, wherein the first pattern comprises:
A pattern detection unit that detects the second pattern and the third pattern, a reference signal formation unit that forms a reference signal indicating an array pitch from the detection signals detected by the pattern detection unit, and a reference signal formation unit A pattern signal forming unit that forms a first pattern signal, a second pattern signal and a third pattern signal from the detection signal detected by the pattern detecting unit based on the generated reference signal; and the pattern signal forming unit. A pattern discriminator that discriminates the first pattern signal and the second pattern signal based on the formed uniform third pattern signal; and a first pattern signal and a second pattern signal near the line of sight. An electronic level comprising: a calculation unit that calculates a height difference from a phase.