JPS6226683B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a form inclination measuring device in an optical character reading device, an optical mark reading device, or the like.

For example, in an optical character reading device, generally a rectangular form on which handwritten characters and/or printed characters are written is run, and an optical detector is used to set the direction orthogonal to the running direction of the form as the main scanning direction and the running direction of the form as the secondary scanning direction. The form is scanned in the scanning direction. Then, after mapping the observed pattern obtained by scanning one line of characters onto the image memory, one character's worth of observed patterns are sequentially extracted from the map, and if necessary, preprocessing is performed on them. After that, the characters are read by extracting the characteristics of that pattern and comparing and matching it with a reference pattern prepared in advance. In order to ensure that the above observation pattern is cut out accurately, a character entry frame is printed for each character on the form, and the person filling out the form writes the characters so that they do not protrude from the frame, and also uses an optical character reader. uses the coordinate system on the form to memorize the positions and dimensions of all the character frames mentioned above, and before scanning the characters on the form, measures the running position and amount of inclination of the form, and calculates these values. is used to determine the cutting position of the observed pattern.
Figure 1 is a principle diagram of a conventional method for measuring the amount of inclination of a form. The amount of inclination of the form is determined by measuring the travel length of the form 1 while the front edge 4 of the form passes between fixed points 2 and 3. This method is nothing but measuring the coordinates of two points on the form to determine the amount of inclination of the form. However, as shown in FIG. 2, a large number of irregularities 5 are present at regular pitches on the sides of a form that has been perforated and separated. This irregular portion 5 often has a convex shape, and its height can reach as much as 2 mm. In Figure 1, side 4 at the front end of form 1
When is in the form shown in Figure 2, two fixed points 2 and 3
When the straight section 6 passes through any of the
The amount of inclination of form 1 can be determined accurately, but if, for example, a straight section 6 passes through one fixed point 2 and an irregular (convex) section 5 passes through the other fixed point 3, the amount of inclination of form 1 can be determined correctly. I can't. As a result, there was a problem in that the observation pattern was not cut out accurately, and therefore the characters were not read accurately.

The present invention has been made to solve these problems, and its purpose is to eliminate the inclination of the form even if there are irregularities caused by perforating the edges of the form and cutting it off. An object of the present invention is to provide a form inclination measuring device which can accurately measure the amount.

In order to achieve the above object, in the present invention,
In a form inclination measuring device having a light detection means arranged to intersect with the moving direction of a relatively moving form, a section length longer than the width of the irregular part at the front end of the form is provided on a straight line along the intersecting direction. providing at least two sections having a plurality of sections, the light detection means including a plurality of detection elements disposed within the sections,
Furthermore, the output state of the detection element is detected, and the coordinates of the two front ends of the form are obtained from the output of the detection elements in each of the sections when a predetermined number or more of the detection elements in the section detect the form for the first time. The present invention is characterized in that means is provided to measure the amount of inclination of the form from the coordinates of the two front end points.

The present invention will be explained in detail below using examples.

FIG. 3 is a principle diagram of an embodiment of the present invention, in which two fixed points 12 and 13 are defined on a straight line included in the running surface of the form 1 and orthogonal to the running direction (indicated by an arrow) of the form 1. Forty-eight sensing elements are closely arranged on each of line segments AB and CD that are centered and perpendicular to the document running direction. Since the diameter of the sensing element is 0.105 mm, the length of each line segment is approximately 5 mm. On the other hand, the width of the irregular portions 5 existing on the front edge side 4 of the form 1 to be used is 1 mm, and the irregular portions 5 occur at a pitch of 6 mm. Therefore, the length of each line segment on which the sensing elements are arranged is greater than twice the width of the irregular portion 5 and shorter than the pitch where the irregular portion occurs. Generally, as in the example above, the width of the irregular part 5 that occurs on the side of the form 1 that has been perforated and separated is approximately the diameter of the sensing element.
It is about 10 times the length and about one-fifth of the length of the straight portion 6. Therefore, if a detection element is provided under the above conditions, two or more irregularities will not occur on each of the line segments, unless the angle between the line segment and the front edge of the form is very large. Therefore, the range through which the irregular portion does not occupy more than half of the length of each line segment. With the detection elements arranged in this way, about half of the detection elements on one line segment detect the front edge of the form, and then about half of the detection elements on the other line segment detect the front edge of the form. By measuring the running length of the form up to this point, the amount of inclination of the form can be measured.

The embodiments of the present invention have been described above with reference to the principle diagrams, but this will now be described in more detail. FIG. 4 is a block diagram showing the configuration of a specific embodiment. The scanning unit 20 scans the form running surface with a main scanning direction in a direction perpendicular to the running direction of the form 10 and a sub-scanning direction in a direction opposite to the running direction of the form,
The black and white information is converted into binary information and stored in the image memory 40 via the gate 30. The microprocessor 50 checks the stored contents of the image memory 40, and when the scanning unit 20 has completed main scanning a predetermined number of times, closes the gate 30 and stops the form running motor 70 via the form running control unit 60. Stop the running of form 10. As a result, image information before and after the front edge of the form is stored in the image memory 40. The scanning section 20 has 2048 photodetecting elements arranged in a one-dimensional manner, thereby scanning a maximum length of 215 mm. Therefore, a length of 0.105 mm in the main scanning direction of the form running surface corresponds to one element of the photodetector. Also, sub-scanning is performed at a pitch of 0.105mm. Therefore, the form running surface is divided into squares of 0.105 mm, and each square corresponds to one bit on the image memory. Now, unlike the explanatory diagram of FIG.
This is performed by the microprocessor 50. FIG. 5 shows the pattern of the front edge of the form stored in the image memory 40 by the microprocessor 5.
It is an explanatory diagram of a pattern in which 0 is scanned. In the following explanation, it is assumed that the white part of the form is stored as 1 and the part outside the form is stored as 0 in the image memory. The microprocessor 50 operates in a straight line parallel to the direction corresponding to the document scanning direction (indicated by an arrow).
The stored content with a width of 48 bits centered on UU' is scanned with the direction perpendicular to UU' as the main scanning direction and the UU' direction as the width scanning direction, and the stored content is examined bit by bit. Find the center X of the first main scanning line where 24 or more bits of 1 are detected. Next, center on a straight line VV′ that is a certain distance from the straight line UU′.
The stored contents with a width of 48 bits are scanned in the same manner to find the center Y of the first main scanning line where 1 of 24 bits or more is detected. The amount of inclination of the form is determined from the X and Y coordinates determined in this way. In the example shown in Figure 5, there is an irregular area 5 within a 48-bit width centered on the straight line VV'.
is included, but the position of Y is between the straight part 6 and the straight line.
It coincides with the intersection of VV′.

As described above, according to the present invention, even if there is an irregular part due to perforation on the side where the amount of inclination of the form is to be detected, the amount of inclination of the form can be accurately measured.

[Brief explanation of the drawing]

Fig. 1 is a diagram of the principle of the conventional example, Fig. 2 is an explanatory diagram of irregularities occurring on the sides of a form, Fig. 3 is a diagram of the principle of the embodiment of the present invention, and Fig. 4 is the configuration of the embodiment of the present invention. 10 is a form, 20 is a scanning unit, and 30 is a block diagram.
40 is a gate, 40 is an image memory, 50 is a microprocessor, 60 is a form running control section, and 70 is a form feeding motor. Further, FIG. 5 is an explanatory diagram of an embodiment of the present invention.

Claims (1)

[Claims] 1. In a form inclination measurement device having a light detecting means arranged to intersect with the moving direction of a relatively moving form, a section length longer than the width of the irregular part at the front end of the form on a straight line along the intersecting direction. at least two sections having:
Each section includes a plurality of detection elements disposed within the section, further detecting the output state of the detection element, and when a predetermined number or more of the detection elements within the section detect the form for the first time. providing means for obtaining the coordinates of two points at the front end of the form from the output of the detection element in the form;
A form inclination measuring device, characterized in that the inclination of the form is measured from the coordinates of the two front ends.