JPH0585004B2 - - Google Patents

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention is a non-contact simultaneous measurement of the length of each side, length of diagonal, and angle of each vertex of a rectangular sheet of paper, plastic, metal thin film, etc. The present invention relates to a method and apparatus for performing.

The invention further relates to a method and apparatus for easily and accurately measuring the dimensions of rectangular sheets of light-sensitive materials such as photographic film, photographic paper, and phototype setting materials.

(Prior Art) Many devices have been known that measure dimensions and the like based on travel distance, but there are only a few that can be done easily and accurately. For example, magnetic linear scales have been put into practical use, but they are expensive if they are used to accurately detect moving distances.

Furthermore, there are few devices that can measure dimensions and angles simultaneously with ease and accuracy.

As a device that can measure dimensions and straightness at the same time with simple operation, Japanese Patent Publication No. 60-57003 describes a measuring stand with orthogonal guides arranged on a reference plane to guide the two vertical and horizontal sides of the sheet to be measured. , 2 of the sheet to be measured located at the corner of the origin and the extension of each guide.
Place it in a total of three corners,
An optical sensor that can detect the position of two sides sandwiching each corner, and an arithmetic circuit that calculates the deviation of the dimensions and squareness of the sheet to be measured from reference values based on the output of the optical sensor. , a sheet size and squareness measuring device consisting of the following elements:

That is, as shown in FIG. 14, two sensors A1, A2, B1, B2, C1, and C2 are arranged near the three corners of the rectangular sheet 4, and the sides 41, 42 of the rectangular sheet 4 are , 43 obstructs the field of view of the sensor, calculate the deviation from the center position of each sensor, and calculate the angle from the reference line of side 41 from the outputs of sensors A1 and C1 to calculate the squareness (second angle). (Fig. 15), and the dimensions of the side 41 (Fig. 16) can be measured from the outputs of the sensors A2 and C2.

According to the device described in Japanese Patent Publication No. 60-57003,
With simple installation and operation, it is possible to measure the dimensions and squareness of a rectangular sheet at the same time. However, in order to accommodate various sizes of rectangular sheets,
The following restrictions were imposed. That is, at the measurement location of a rectangular sheet, it is necessary to cut out the guide that guides the rectangular sheet, and to make a hole in the measuring table for the light emission and reception of the optical sensor. was limited to the size of

(Technical Problem) The purpose of the present invention is to solve the above-mentioned constraints,
The present invention aims to provide a method and apparatus for optically and easily measuring the length of each side, the length of a diagonal, and the angle of each vertex with high accuracy in response to various sizes and shapes of rectangular sheets. .

(Technical means) This purpose is to calculate the length and diagonal of each side of the rectangular sheet based on the projection image information of the three vertices of the rectangular sheet and the reference scale placed in the vicinity, and the position information of the reference scale. A method for measuring dimensions of a rectangular sheet, characterized by calculating the length of an image and the angle formed by each vertex, and a transparent mounting table having two orthogonal linear light sources, an origin light source, and a reference scale, a reading unit having a two-dimensional image sensor and a photoelectric sensor and movably attached to a position opposite to the light source by sandwiching the mounting base; This is achieved by a rectangular sheet dimension measuring device characterized by comprising an image processing device that calculates the length of each side, diagonal line length, and angle formed by each vertex of the rectangular sheet.

(Function) The structure and function of the present invention will be explained in detail below based on the attached drawings.

FIG. 1 is an external view of the device according to the present invention,
The reference scale plate 5 is fixed on the transparent mounting table 1 with a pressing plate 53, and the X-axis linear light source 31 and the Y-axis linear light source 31 are mounted on it.
An axial linear light source 32 and an origin light source 33 are arranged. It also outputs images and calculation results.
A CRT 12, printer 13 and operation panel 14 are arranged on the right side.

As shown in FIG.
3. A reading device having a transparent mounting table 1 having a reference scale 5, a two-dimensional image sensor 25 and a photoelectric sensor 28, and movably attached to a position opposite to the light sources 31, 32, 33 with the mounting table 1 in between. From an image processing device 11 that receives position information and projected image information from the section 2 and the reading section and measures the length of each side, the length of a diagonal, and the angle formed by each vertex of the rectangular sheet 4 on the mounting table 1. configured. Reading section 2
is movable in the X-axis and Y-axis directions by a moving mechanism 27.

FIG. 3 is a block diagram showing the overall device configuration. Light from the light source 3 passes through the diffuser plate 34, projects images of the vertices of the rectangular sheet 4 and the reference scale plate 5 onto the reading section 2, and the reading section The image signal from 2 is sent to the image calculation processing device 11, and the calculation result is sent to the CRT.
12 and printer 13.

As described above, the light source section 3 is composed of two orthogonal linear light sources 31 and 32 and an origin light source 33 (FIGS. 1 and 2). For example, a high frequency fluorescent lamp is used as the light source.

FIG. 4 shows an enlarged plan view of the two-dimensional image sensor 25 used in the reading unit 2 of the present invention.
The light-receiving elements 26 are two-dimensionally arranged horizontally by n _x pieces and vertically by n _y pieces.

FIG. 5 shows the reference scale plate 5 in the horizontal direction (X
The arrangement of scales 51 used for the axis) is shown. This scale plate has a two-dimensional image sensor 25.
Graduation marks 51 having an arbitrary line width W' wider than the resolution of the CCD light-receiving element 26 are arranged at equal intervals W _x . The scale 52 provided at a vertically distant position is used to actually measure the vertical and horizontal distances W _x and W _y from the opposing scale 51 to obtain the resolution used in the calculations described below.

CCD light receiving element 2 of two-dimensional image sensor 25
The resolution of 6 is between known intervals W _x and between W _y .
When the CCD light-receiving elements 26 are included in u _x and u _y pieces, it is determined by a calculation formula.

Horizontal resolution R _x = W _x / u _x Vertical resolution R _y = W _y / u _y At this time, the effective field of view of the two-dimensional image sensor 25 is L a = R x・n x in the horizontal direction and L _a = R _x・n _x in the vertical direction. In the direction L _b = R _y・
n _y .

At least two scales 51 are arranged so as to be included within this field of view.

The reference scale plate 5 uses a transparent substrate (for example, glass) that does not change in size, and the scale 51 is formed thereon by metal vapor deposition (for example, chromium vapor deposition).

When performing measurement using such a reference scale plate 5 (FIG. 6), the reading section 2 moves parallel to the direction of the scale 51 on the reference scale plate 5.

The position of the reading unit 2 is calculated by detecting position detection works 29 provided at intervals of W _x with a photoelectric sensor 28. The reading unit 2 is fed in steps at intervals of W _x , and at least two scale marks 51 appear within the field of view.

The illumination light from the light source 3 is averaged over a wide area through the diffusion plate 34, and the scale 51 of the reference scale plate 5 and the apex of the rectangular sheet 4 are projected onto the reading section 2. The reading section 2 moves while checking the screen of the CRT 12 so as to project the vertices of the rectangular sheet 4 (FIG. 3). The above configuration is the same in the vertical direction (Y-axis).

The reading section 2 includes, for example, an X-axis reading head 21 and a Y-axis reading head 21.
It consists of an axis reading head 22 and an origin reading head 23 (FIG. 7), and each reading head 21, 22, 23 has a two-dimensional image sensor 25 and a photoelectric sensor 28, as described above.

Referring to Figures 7, 8, 9, and 10 below, 3
The reading heads 21, 22, and 23 are arranged, and the length of each side, the length of the diagonal, the vertices A and B are determined from the positional information of the three vertices A, B, and C of the rectangular sheet 4 and the projected image information. - Explain how to calculate the angle of C.

FIG. 7 shows the arrangement of the three reading heads 21, 22, 23, and FIG.
52 is shown. At this time, the reading head 21,
The images projected on 22 and 23 are as shown in FIG.
It will be like 3.

In FIG. 10, each vertex A, B,
The positional relationship on the coordinates of C, the scale 51 of the reference scale plate 5, etc. is shown.

From the images projected onto the field of view of the reading heads 21, 22, and 23, the positional information of the reference point of the scale 51 (for example, the vertex of the L-shaped corner) and the respective vertices A, B, and C of the rectangular sheet 4 is obtained. is read, input to the image processing device 11, performs arithmetic processing as shown below, and outputs to the CRT 12 and printer 13.

In Figure 9 1 and Figure 10, the reference scale
If the position coordinates of A' are (L ₁ , O), then L ₁ = l ₁ + 2・W _x where W _x is the horizontal scale turn interval l ₁ is the second left scale position of A' ( distance from the origin (outside the field of view) The position coordinates of the vertices A and A' of the rectangular sheet 4 are
A(x ₁ , y ₁ ), A'(l _x1 ,
l _y1 ), then the position of vertex A (X ₁ , Y ₁ ) is horizontal direction X ₁ = L ₁ −R _x1 × | l _x1 − x ₁ | vertical direction Y ₁ = R _y1 × | l _y1 − _{y 1} | However, R _x1 and R _y1 indicate the horizontal and vertical resolutions of the two-dimensional image sensor 25, respectively.

Reference scale shown in Figure 9 2 and Figure 10
Similarly, for B' (O, L ₂ ) and vertex B (X ₂ , Y ₂ ), X ₂ = R _x2 | l _x2 − x ₂ | Y ₂ = L ₂ − R _y2 × | l _y2 − _{y 2} ｜ Here, L ₂ = l ₂ + 1・W ₂ However, l ₂ is the distance from the origin of the scale position next to B', and the reference scale shown in Figure 9 3 and Figure 10.
Similarly, for C'(O, O) and vertex C(X ₃ , Y ₃ ), X ₃ = R _x3 × | l _x3 − x ₃ | Y ₃ = _{R x3 × |} From the coordinates, the length of each side and diagonal, and the angle formed by the vertex are calculated according to well-known mathematical theorems. That is, horizontal direction =√{( ₁ − ₃ ) ² + ( ₁ − ₃ ) ² } vertical direction =√{( ₂ − ₃ ) ² + ( ₂ − ₃ ) ² } diagonal =√{( ₂ − ₁ ) ² +( ₂ − ₁ ) ² } Angle of vertex B∠ACB=cos ^-1 {( ² + ² −
^2/2 ...} Example 1 Hereinafter, an example in which measurements were performed based on the apparatus configuration of the present invention shown in FIGS. 1 to 10 will be described.

The two-dimensional image sensors 25 of the three reading heads 21, 22, and 23 all have the number of pixels, horizontal n _x =
780, vertical n _y = 490 CCD light receiving elements 26,
The size of one of the CCD light receiving elements 26 is a horizontal
= 11 μm and vertical b = 13.5 μm. The interval between the scales 51 and 52 on the reference scale plate 5 is the same both vertically and horizontally, W _x = W _y = 20 mm, and the line width of the scale pattern is
W′=0.6mm.

The reference scale plate 5 was made of transparent glass with scales 51 deposited by chromium vapor deposition, and the light sources 31, 32, and 33 were high-frequency fluorescent lamps.

The resolution of this two-dimensional image sensor 25 is
Equal to the size of the CCD light receiving element 26, 11 μm in width,
Although the length is 13.5 μm, the effective resolution on the measurement surface through the lens optical system of the reading section is 0.053 mm horizontally,
The height is 0.069mm.

As Example 1, the dimensions are 252.5 mm in width and 303.0 mm in height.
Measurement accuracy (3σ) when measuring the standard rectangular sheet of
was N=20, width 0.104 mm, length 0.026 mm, and apex angle 0.025°.

On the other hand, when measuring the same standard rectangular sheet using a conventional ruler, the 3σ accuracy is 0.380 horizontally.
mm, and the height was 0.215 mm.

Example 2 With the same device configuration, the dimensions were 507.0 mm in width and 507.0 mm in height.
The measurement accuracy (3σ) when measuring a standard rectangular sheet of 609.0 mm is N = 20, width 0.027 mm, height 0.045 mm,
The angle at the apex was 0.015°.

On the other hand, when measuring the same standard rectangular sheet using a conventional ruler, the 3σ accuracy is 0.284 horizontally.
mm, and the height was 0.176 mm.

(Change in configuration) As an example of changing the embodiment, the 11th, 12th, 1st
A device configuration as shown in FIG. 3 is also possible. That is, FIG. 11 shows that the scale 51 of the reference scale plate 5 may be made into a cross shape instead of the L shape shown above, and the center of the point that intersects the reference coordinate position may be taken. .

As shown in FIG. 12, even when measuring, for example, a triangle instead of the rectangular sheet 4, the scale 5
1 (+-shaped in the case of FIG. 12) are two-dimensionally arranged over the entire surface, it is possible to measure objects of any size and shape.

As shown in FIG. 13, even if the parallelism of the corresponding sides of the rectangular sheet 4 is slightly off, by arranging the four reading sections 21, 22, 23, and 24, the length of all sides and the total This shows that it is possible to obtain accurate dimension data regarding the length of diagonals and the angles of all vertices.

(effect) This invention has the following unique effects.

It is composed of items that can be easily produced or obtained, such as a reference scale plate, two-dimensional image sensor, photoelectric sensor, etc., and enables inexpensive and highly accurate width and angle measurements.

The arrangement of the measurement system can be freely selected for various sizes and shapes of objects to be measured, providing sufficient versatility.

[Brief explanation of the drawing]

Fig. 1 is an external view of the present device, Fig. 2 is an elevational view thereof, Fig. 3 is a principle diagram of position detection of the reading section 2,
FIG. 3 is a block diagram showing the configuration of the device of the present invention, and FIG.
The figure is an enlarged plan view of the two-dimensional image sensor of the reading section of the apparatus of the present invention, and FIG. 5 shows an example of the scale of the reference scale plate. FIG. 6 is a diagram showing the position detection principle of the reading section of the apparatus of the present invention. Figure 7 is 3
Figure 8 shows the arrangement when measuring the dimensions of a rectangular sheet using multiple reading heads. Figure 10 shows the relative positions on the overall coordinates. FIG. 11 shows an example of a cross-shaped scale, FIG. 12 shows the arrangement of a triangular sheet measurement example, and FIG. 13 shows the arrangement when obtaining dimension information of all sides and vertices of a rectangular sheet.
FIG. 14 is a diagram showing the arrangement of sensors in a conventional device, FIG. 15 is a diagram showing its squareness measurement principle, and FIG. 16 is a diagram showing its side length measurement principle. 1... Mounting table, 11... Image calculation processing device, 1
2...CRT, 13...Printer, 14...Operation panel, 2...Reading section, 21, 22, 23, 24
... Reading head, 25 ... Two-dimensional image sensor, 26 ... CCD light receiving element, 27 ... Movement mechanism,
28... Photoelectric sensor, 29... Position detection work, 3... Light source section, 31, 32, 33... Light source,
34...Diffusion plate, 4...Rectangular sheet, 41,4
2, 43...side of rectangular sheet, 5... reference scale plate, 51, 52... scale, 53... presser plate.

Claims (1)

[Claims] 1. Based on the projection image information of the three vertices of the rectangular sheet and the reference scale placed in the vicinity thereof and the position information of the reference scale, the length of each side of the rectangular sheet and the diagonal image of the rectangular sheet are determined. A method for measuring dimensions of a rectangular sheet, characterized by calculating the length and the angle formed by each vertex. 2. It has two orthogonal linear light sources, an origin light source, a transparent mounting table having a reference scale, a two-dimensional image sensor and a photoelectric sensor, and is movably attached to a position opposite to the light source by sandwiching the mounting table. reading section,
The length of each side of the rectangular sheet on the mounting table is determined by receiving position information and projected image information from the reading unit.
A size measuring device for a rectangular sheet, comprising an image processing device that calculates the length of a diagonal and the angle formed by each vertex.