JPH07302312A - Machine reading mark and its reading device - Google Patents

Abstract

PURPOSE:To provide a highly reliable machine reading mark capable of reducing the influence of printing distortion due to a mechanical or electric factor in a recorder and capable of accurate sampling without losing a synchronizing pattern nor reading a position deviated from the center of a data line. CONSTITUTION:This machine reading mark is constituted of a coordinate detecting pattern area consisting of black and white patterns, a synchronizing pattern area and a data pattern area 3, the area 3 is formed by a data pattern string obtained by arraying a data pattern arrayed in a 1st direction in a 2nd direction vertical to the 1st direction at an interval Dy and the area 1 is formed by a synchronizing pattern array arraying four kinds of strings in a 1st direction by shifting a synchronizing pattern arraying black patterns 1-7, 21, 25 having two kinds of synchronizing reference sides in which the length in the 2nd direction is 2Dy and white patterns having 2Dy length in parallel in the 2nd direction at an interval Dy.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a machine reading mark recorded on a recording medium such as paper or a sheet and a reading device therefor.

[0002]

2. Description of the Related Art Bar code technology has been conventionally known as an image coding technology. However, in the case of a bar code, there is a limit in the amount of information that can be recorded due to its structure, and there is a problem that the recording density cannot be increased. It was

In order to solve the above problem, a machine reading mark has been developed in which data patterns formed by patterns (bright and dark portions) having different reflectances are two-dimensionally arranged at minute intervals. Since each data bit is represented by a dark portion and a dark portion, the recording density can be significantly improved.

As a data reading method for the above-mentioned data structure, a synchronization pattern having position information for reading the data is arranged around the data area in which the data is arranged, and the data is obtained from the position information of the data pattern obtained from the synchronization pattern. A method of calculating the sampling position and reading the data was devised (for example, Japanese Patent Laid-Open No. 2-1738).
No. 79).

An example of the above-mentioned conventional mechanical reading mark and its reading device will be described below with reference to the drawings with reference to FIGS. 11 to 16. FIG. 11 shows the first
FIG. 7 is a diagram showing a machine reading mark that is a conventional example of FIG. In FIG. 11, the machine read mark is composed of a Y pattern 1 and an X clock 2 which are synchronization patterns, a data part 3 which is a data region, a tilt detection line 4 and a reference position detection mark 5 which are coordinate pattern regions. And
Each area is formed of a black pattern having a low reflectance and a white pattern having a high reflectance.

In the data part 3, in order to represent the data "10101010 ...", which is the data formed in the data part 3, by the black pattern and the white pattern, the bit "1" is expressed by the black pattern and the white Bit "0" is expressed in the pattern. This black-and-white pattern has an interval Dx in the main scanning direction of the machine reading mark (hereinafter referred to as the main scanning direction of the mark).
Are arranged, and the arrangement of this data is used as a data line. A plurality of data lines are arranged in parallel with the main scanning direction of the marks, and the data line interval in the sub-scanning direction of the machine reading marks (hereinafter referred to as the sub-scanning direction of the marks) is Dy. Dx and Dy are generally set according to the recording density of the recording device and the resolution characteristic of the reading device.

The Y clock 1 is for designating a synchronous reference position of the mark in the sub-scanning direction, and a black pattern and a white pattern are periodically arranged in the sub-scanning direction of the mark. The sub scanning direction length Vy1 of the black pattern mark of the Y clock 1 and the sub scanning direction length Vy2 of the white pattern mark are determined by the data line interval Dy of the data section 3. The relationship is Vy1 = Vy2 = Dy. Further, the length Vx1 of the marks of the black pattern and the white pattern in the main scanning direction is equal to Dx here, but may be any value not less than Dx.

The X clock 2 is for designating a synchronous reference position of the mark in the main scanning direction, and a black pattern and a white pattern are periodically arranged in the main scanning direction of the mark. An interval Hx1 between the center of the first X clock (black pattern) 26 and the center 29 of the second X clock (white pattern) in the main scanning direction of the mark, the center 29 of the second X clock (white pattern) and the third X clock (black pattern). The distance Hx2 from the center of 27 is determined by the distance Dx between the data in the data section 3. The relationship is Hx1 = Hx2 = Dx. Here, the interval Hx0 in the main scanning direction between the Y clock 1 and the first X clock 26 and the marks of the data section 3 is D
It may be any value equal to x but not less than Dx. Further, the length Hy of the mark of the X clock 2 in the sub-scanning direction and the interval Dy0 of the mark of the X clock 2 and the data part 3 in the sub-scanning direction are equal to Dy, but may be any value not less than Dy. This machine reading mark is used as the inclination detecting means 7 of the reading device of FIG.
An image processed by the reference position detecting means 8 is shown in FIG.

FIG. 12 is a diagram for explaining the operation of the mechanical reading mark of FIG. 11 and the synchronization pattern detecting means and data sampling means in the reading device of FIG.
In FIG. 12, the synchronization pattern detecting means 9 and the data sampling means 1 are used by using the image data processed by the tilt detecting means 7 and the reference position detecting means 8 (details will be described later) of FIG.
0 will be briefly described. The synchronization pattern detecting means 9 detects the centers of the Y clock 1 and the X clock 2 and outputs the reference position coordinates to the data sampling means 10. The data sampling means 10 uses the reference position coordinates in the X direction and Y direction.
The data sampling position is calculated from the later-described sampling line of the direction.

The first sampling line 39 in the Y direction is the first
It is a line that passes through the center position 47 of the Y clock 17 and is substantially parallel to the X direction.
Is a line that passes through the center position 49 of the second Y clock 21 and is substantially parallel to the X direction. The second sampling line 40 in the Y direction passes through the midpoint 48 between the center position 47 of the first Y clock 17 and the center position 49 of the second Y clock 21.
It is a line almost parallel to the direction. Similarly, the Y-direction fourth sampling line 42, the Y-direction fifth sampling line 43, the Y-direction sixth sampling line 44, and the Y-direction seventh sampling line 45 are set to the center position of each Y clock and the midpoint between the center positions. It can be obtained from the position.

On the other hand, the X direction first sampling line 31
Is a line substantially parallel to the Y direction passing through the center position 28 of the first X clock 26, and the second sampling line 32 in the X direction is a line substantially parallel to the Y direction passing through the midpoint position 29 of the second X clock. Similarly, the third sampling line 33 in the X direction and the fourth sampling line 3 in the X direction
4, the X-direction fifth sampling line 35, the X-direction sixth sampling line 36, and the X-direction seventh sampling line 37 can be obtained from the center positions of the respective X clocks.

As described above, the Y-direction first sampling line 39 and the X-direction first sampling line 31 described above are used.
The data on the data line 38 can be read by sampling the data sampling position 38a which is the intersection of Hereinafter, similarly, the first sampling line 39 in the Y direction and the second sampling line 3 in the X direction
Data sampling position 38b, which is the intersection with 2, and X
Data sampling position 38c, which is the intersection with the third sampling line 33 in the direction, and data sampling position 38d, which is the intersection with the fourth sampling line 34 in the X direction.
And a data sampling position 38e which is an intersection with the X-direction fifth sampling line 35, a data sampling position 38f which is an intersection with the X-direction sixth sampling line 36, and an X-direction seventh sampling line 37. The black pattern and the white pattern of the data part 3 in FIG. 11 can be read as bits "1" and "0" by sampling the intersection with the data sampling position 38g. In this way, the data section 3 can be read from the data sampling position calculated by the sampling line in the Y direction calculated from the Y clock 1 and the sampling line in the X direction calculated from the X clock 2.

FIG. 13 is a diagram showing a print sample in which the machine reading mark of FIG. 11 is output using a recording device. In FIG. 13, T1 and T2 indicate the length of the normally printed synchronization pattern in the paper feed direction (sub-scanning direction of the recording device) of the recording device. Further, T3, T4, T5, and T6 indicate the lengths of synchronization patterns that are not printed normally. Originally, it is desirable that all lengths T have the same relationship, but since various disturbance elements are mixed in the actual recording apparatus, there are cases where all lengths are not equal. In this example, T1 = T2 = Dy1, T3, T5>Dy1> T
4, T6, and Dy1 is a data line interval in the sub-scanning direction of the recording apparatus.

The reason for T3, T5>Dy1> T4, T6 is that mechanical factors are not constant in the feed pitch of the recording paper when the machine reading marks are printed on the recording paper, and when a FAX machine is used as the recording machine. There is an electrical factor due to a transmission error (when one line in the main scanning direction is lost, data of the previous line is interpolated) that occurs when transmitting and receiving the reading mark.

FIG. 14 is a diagram showing an output waveform after the synchronization pattern of FIG. 13 is read by the reading device of FIG. In FIG. 14, 14a is Y in the sub-scanning direction of FIG.
An image of clock 1 is shown. 14b reads between the line segments AB of 14a using a reading device having sufficient resolution characteristics,
It is the output analog signal waveform. The horizontal axis represents the position between the line segments AB, and the vertical axis represents the output voltage of the reader. 1
Reference numeral 4c is an analog signal waveform output by reading 14a using an inexpensive reading device having a poor resolution characteristic. VT shown in the figure is a binarized slice level for performing binarization processing for converting an analog signal into a digital signal.
When the voltage is lower than this binarized slice level VT, it is judged as "0" (white), and when it is high, it is "1".
A digital signal can be obtained by determining (black). The result is shown in waveform 14d. Waveform 14d
Indicates the waveform after binarization, and the T4 section in the figure is originally "
It can be seen that it should be "1", but it is "0". Also, it can be seen that the T6 section in the figure is "1" although it should have been "0". Since it is designed in consideration of the data line interval Dy1 from the resolution characteristic, the resolution characteristic is insufficient for Dy1> T4 and T6, and it is possible to faithfully respond to the synchronization pattern during the period of T4 and T6. Therefore, the image data after the binarization process (synchronization pattern between T4 and T6 sections) disappears, resulting in a result different from the original synchronization pattern. Thus, if the synchronization pattern disappears and cannot be detected normally, The synchronization pattern detection means 9 described in FIG. 2 outputs an incorrect synchronization reference position to the data sampling means 10, and the data sampling means 10 outputs X based on the incorrect synchronization reference position.
Since the sampling lines and the sampling positions in the Y direction and the Y direction are calculated, the read data has a different number of data, and thus a normal read operation cannot be performed.

FIG. 15 is a view showing a machine reading mark which is a second conventional example. In FIG. 15, a Y clock 1 is used to indicate a synchronization reference position of the mark in the sub-scanning direction, and black patterns and white patterns are periodically arranged in the sub-scanning direction of the mark. The sub scanning direction length Vy1 of the black pattern mark of the Y clock 1 and the sub scanning direction length Vy2 of the white pattern mark are determined by the data line interval Dy of the data section 3. The relationship is Vy1 = Vy2 = 2 * Dy. Other patterns are the same as the configuration described in FIG. 11.

FIG. 16 is a diagram showing a sample of the machine reading mark of FIG. 15 when the same print distortion as in FIG. 13 occurs. In FIG. 16, the same print distortion as in FIG. 13 is generated, but the length of the synchronization pattern in the Y direction is Dy1.
It is clear that the sync pattern does not disappear even if it is read using the reader of FIG. 2 (double the value of Dy1). The reading method will be briefly described using the reading device shown in FIG. Figure 2
The sync pattern detecting means 9 of the
The edge which is the boundary between the center of the clock 1 and the black pattern and the white pattern is detected and output to the data sampling means 10 as the synchronization reference position. Thereafter, similarly to the contents described with reference to FIG. 12, the data sampling means 10 detects the sampling lines S in the X direction (not shown) and the Y direction from the synchronization reference position and reads the data. But,
Since the data line D and the sampling line S in the Y direction are deviated from d1 to d4 due to printing distortion, a position deviated from the center of the data line is read and an incorrect result is output.

[0018]

As described above, the above-described structure has a problem that accurate sampling cannot be performed when print distortion occurs due to mechanical or electrical factors of the recording apparatus. Was there.

In view of the above problems, the present invention reduces the influence of print distortion by the recording device, and does not erase the synchronization pattern, and does not read the position deviated from the center of the data line, so that accurate sampling is performed. It is an object of the present invention to provide a highly reliable machine-readable mark and a reading device therefor capable of performing the above.

[0020]

In order to solve the above problems, the machine reading mark of the present invention has a plurality of data patterns formed by arranging a plurality of data patterns in which data is encoded in a first direction. A data pattern area formed by arranging columns in a second direction perpendicular to the first direction at a predetermined interval L and a synchronization reference side parallel to the first direction are arranged one on each side of the synchronization pattern. The position of the synchronization reference side in the second direction as the synchronization reference position, and the synchronization reference side on the leading edge side with respect to the second direction of the synchronization pattern is the first synchronization reference side and the second synchronization reference side.
And the synchronization reference side on the trailing edge side as the second synchronization reference side, the distance between the synchronization reference sides on both sides of the synchronization pattern is X times L (X is an integer of 2 or more) and the synchronization pattern is A row of Ys of L in the second direction
N times L (N
Are formed by arranging a plurality of them at equal intervals (the sum of X and Y), and arranging the synchronization pattern rows in the first direction by at least N types of rows that are parallelly offset by a distance L in the second direction. And a coordinate detection pattern region formed by arranging a tilt detection pattern that defines the first direction or the second direction and a reference position detection pattern that indicates a reference position. The position of each data pattern sequence in the second direction is arranged at the midpoint between the synchronization reference positions adjacent to each other at the interval L.

Further, in the reading apparatus of the present invention, an image input means for reading the image of the machine reading mark and outputting image data, and a main scanning direction of the image input means based on the image data output by the image input means. Alternatively, an inclination detection unit that detects the angle formed by the inclination detection pattern with respect to the sub-scanning direction to detect the first or second direction, and a reference position detection that detects the coordinates of the reference position detection pattern indicating the reference position. Means, the tilt detecting means, and the first or second direction and coordinates detected by the reference position detecting means are used to detect the synchronization pattern from the image data, and the first synchronization reference edge or The sync pattern detecting means for detecting the second sync reference side and the sync reference position detected by the sync pattern detecting means are Contact the first set the middle point to the data pattern read reference position of the position in the second direction between the synchronous reference side and the second synchronization reference edge, in which a data sampling means for reading a data pattern.

[0022]

According to the present invention, by the above-mentioned constitution, even when the printing distortion occurs due to the mechanical or electric factor of the recording apparatus, the sampling can be accurately performed with the simple constitution without losing the synchronization pattern, and each data pattern can be recorded. It can be read reliably.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a configuration of a machine reading mark that is a first embodiment of the present invention. In FIG. 1, the machine reading marks are the Y clock 1 and the X clock 2 which are synchronous pattern areas, the data portion 3 which is a data pattern area, and the tilt detection line 4 which is a coordinate detection pattern area.
And the reference position detection mark 5.
Each area is composed of a black pattern having a low reflectance and a white pattern having a high reflectance.

In the data part 3, in order to represent the data "01010101 ...", which is the data formed in the data part 3, by the black pattern and the white pattern, the black pattern is represented by the bit "1". , White pattern bit "0"
Is expressed. The black-and-white patterns are arranged at intervals Dx in the main scanning direction of the marks, and are arranged at intervals Dy in the sub-scanning direction of the marks. Dx and Dy are values set by the recording density of the recording device and the resolution characteristic of the reading device.

The Y clock 1 is for designating the synchronization reference position of the mark in the sub-scanning direction, and is composed of a plurality of columns in which black patterns and white patterns are periodically arranged in the sub-scanning direction of the mark. Are arranged in the main scanning direction, and the respective columns are arranged in parallel with the sub-scanning direction of the marks and shifted by the data line interval Dy of the data section 3.
The length Vy1 of the black pattern mark of the Y clock 1 in the sub-scanning direction and the length Vy2 of the white pattern are determined by the data line interval Dy of the data section 3. The relationship is V
y1 is X1 * Dy, Vy2 is X2 * Dy (X1, X2 are integers of 2 or more), and the period in which the black pattern and the white pattern are arranged is N (the sum of X1 and X2). The number of columns is N. In FIG. 1, X1 and X2 are 2, and the period and the number of columns N are 4.

The X clock 2 is for designating a synchronization reference position of the mark in the main scanning direction, and black patterns and white patterns are periodically arranged in the main scanning direction of the mark. An interval Hx1 between the center of the first X clock 26 (black pattern) in the main scanning direction of the mark and the center 29 of the second X clock (white pattern) and the center 29 of the second X clock (white pattern) in the main scanning direction of the mark The distance Hx2 from the center 30 of the 3X clock (black pattern) 27 is determined by the data section 3
Is determined by the distance Dx between the data. The relationship is Hx1 = Hx2 = Dx. Here, the interval Hx0 in the main scanning direction between the first Y clock 20 and the first X clock 26 of the fourth column and the mark of the data portion 3 is equal to Dx, but may be any value not less than Dx. Further, the length H of the mark of the black pattern and the white pattern of the X clock 2 in the sub-scanning direction
The distance Dy0 between y and the X clock 2 and the mark of the data portion 3 in the sub-scanning direction is equal to Dy and twice the Dy, respectively, but may be any value greater than or equal to the Dy and twice the Dy.

With the above configuration, it is possible to read the data part 3 by detecting the synchronization reference position for reading the data part 3 from the Y clock 1 and the X clock 2 (details will be described later).

FIG. 2 is a view showing the arrangement of a reading device for reading a machine reading mark according to an embodiment of the present invention. In FIG. 2, the image input means 6 reads the image of the machine reading mark of FIG. 1 and outputs the image data 11 to the inclination detection means 7. The tilt detecting means 7 is the image inputting means 6.
The angle between the tilt detection line 4 of FIG. 1 and the main scanning direction of the image input means 6 is detected based on the image data 11 output from the above, and the mark tilt signal 12 is output to the reference position detection means 8. The reference position detecting means 8 is an inclination detecting means 7.
The mark tilt signal 12 output from the image output means and the image input means 6
The reference position is detected from the reference position detection mark 5 of FIG. 1 based on the image data 11 output from the above, and the reference position coordinates 13 are output to the synchronization pattern detecting means 9. The synchronization pattern detecting means 9 detects the positions of the synchronization patterns of the Y clock 1 and the X clock 2 of FIG. 1 based on the reference position coordinates 13 output from the reference position detecting means 8 and the image data 11, and detects the positions of the synchronization patterns. The coordinates 14 are output to the data sampling means 10. The data sampling means 10 is
The data sampling position is calculated on the basis of the position coordinates 14 of the sync pattern output from the sync pattern detecting means 9 and the image data 11, and the data section 3 of FIG. 1 is read from the image data 11 (of each section). Details will be described later).

FIG. 3 is a diagram showing an example of an image after the mechanical reading mark of FIG. 1 is read by the image input means of FIG. In FIG. 3, an angle θ formed by the dotted lines 15 passing through the center points 4a and 4b at both ends of the tilt detection line 4 and the main scanning direction is illustrated. The inclination detecting means 7 in FIG.
Positional coordinates (x1, y1) and (x2, y2) of a and point 4b
Can be detected and the angle θ can be calculated. Also, FIG.
The reference position detecting means 8 can detect the center of gravity or the center of the reference position detection mark 5 to obtain the reference position coordinates (x0, y0).

FIG. 4 is a diagram showing an image after inclination correction. In FIG. 4, the image read while correcting the image 11 by using the inclination θ detected by the inclination detection unit 7 of FIG. 2 and the reference position coordinates (x0, y0) obtained by the reference position detection unit 8 is displayed. Shows. It can be seen that the main scanning direction and the sub scanning direction of the machine reading mark in FIG. 1 correspond to the X and Y directions in FIG. 4, and the inclination (θ = 0 °) of each pattern is corrected.

FIG. 5 shows the machine reading mark of FIG. 1 and FIG.
FIG. 6 is a diagram for explaining the operations of the synchronization pattern detection means and the data sampling means in the reading device. In FIG. 5, the operation of the synchronization pattern detecting means 9 and the data sampling means 10 of FIG. 2 will be described by enlarging a part of FIG. The synchronization pattern detection means 9 detects the edge coordinates which are the synchronization reference position of each black pattern on the edge search lines 5a, 5b, 5c, 5d parallel to the Y direction, and the data sampling means 10 detects the edge coordinates of the black pattern. The sampling lines and the data sampling positions in the X and Y directions are calculated from the above. The details will be described below.

The first sampling line 39 in the Y direction is the falling edge coordinate 18 of the first Y clock 18 in the second column.
b and the middle point between the rising edge coordinates 19a of the first Y clock 19 in the third column or the first Y clock 17 in the first column
Of the falling edge coordinates 17b of the fourth column and the rising edge coordinates 20a of the first Y clock 20 of the fourth column are calculated, and either one of these middle points or the X direction passing through the average value of these middle points is approximately The second sampling line 40 in the Y direction is a parallel line, and the rising edge coordinates 20a of the first Y clock 20 in the fourth column and the first sampling line in the third column.
The midpoint between the falling edge coordinates 19b of the Y clock 19 or the midpoint between the falling edge coordinates 18b of the first Y clock 18 in the second row and the rising edge coordinates 21a of the second Y clock 21 in the first row is calculated. The line is substantially parallel to the X direction and passes through either one of these midpoints or the average value of these midpoints.

Similarly, either one of the rising edge coordinate (edge a) or the falling edge coordinate (edge b) of the adjacent black pattern of each Y clock is different from the edge (edge a and edge b or edge b or edge b). Y parallel to the X direction passing through the midpoint between edge b and edge a)
The direction sampling line can be calculated. In this way, around the sampling line in each Y direction,
The Y clock 1 is arranged so that there are always two sets of different types of edges.

On the other hand, the X direction first sampling line 31
Is a line that is substantially parallel to the Y direction passing through the center position 28 of the first X clock 26, and the second sampling line 32 in the X direction is a line that is substantially parallel to the Y direction passing through the midpoint position 29 of the second X clock. . Similarly, the third sampling line 33 in the X direction, the fourth sampling line 34 in the X direction, the fifth sampling line 35 in the X direction, and the sixth sampling line in the X direction.
The sampling line 36 and the X-direction seventh sampling line 37 can be obtained from the center position of each X clock.

As described above, the data on the data line 38 can be read by sampling the data sampling position 38a, which is the intersection of the Y-direction first sampling line 39 and the X-direction first sampling line 31 described above. . Hereinafter, similarly, the first sampling line 39 in the Y direction and the second sampling line 32 in the X direction
And a data sampling position 38b which is an intersection of the X direction third sampling line 33 and a data sampling position 38d which is an intersection of the X direction fourth sampling line 34.
And a data sampling position 38e which is an intersection with the X-direction fifth sampling line 35, a data sampling position 38f which is an intersection with the X-direction sixth sampling line 36, and an X-direction seventh sampling line 37. The black pattern and the white pattern of the data part 3 in FIG. 1 can be read as bits "1" and "0" by sampling the intersection with the data sampling position 38g. In this way, the data pattern 3 is composed of the synchronous pattern detecting means 9 for detecting the edge coordinates of the black pattern and the data sampling means 10 for calculating the sampling lines and the data sampling positions in the X and Y directions from the edge coordinates.
Can be read.

As described above, four columns of Y clocks, each column having a pattern of cycle 4, have been described, but in the case of a cycle N, it will be explained that Y clocks of N rows or more are generally required.

In order to read the data part 3, the data sampling means 10 calculates sampling lines in the X and Y directions from the sync reference position detected by the sync pattern detecting means 9. In the reading method of the present embodiment, since two edges having different rising and falling types are used to calculate one sampling line in the Y direction, the sampling lines in the Y direction are continuously calculated without gaps. In order to do so, it is necessary to always have two sets of different types of edges around the sampling line in the Y direction. To this end, the Y clock may be configured so that there are one edge of different type at each synchronization reference position.

Here, the Y coordinate of the rising edge of the first Y clock in the first column is 0, the Y coordinate of the rising edge of the first Y clock in the second column is Dy, and the Y coordinate of the rising edge of the first Y clock in the third column is When the Y coordinate is 2 * Dy, the Y coordinate of the rising edge of the first Y clock in the nth column is (n-1) * Dy. Similarly, the first Y in the first row
Since the Y coordinate of the falling edge of the clock is Vy1 which is the length of the black pattern, the Y coordinate of the falling edge of the first Y clock in the n-th column is Vy1 + (n-1) * Dy. Y of the rising edge of the second Y clock of the column
The coordinates are Vy1 + Vy2. Each row has an interval Dy in the Y direction
The lengths Vy1 and Vy2 of the black pattern and the white pattern are parallel to each other and are an integral multiple of Dy (X1, X
2), the Y coordinate (n-1) * Dy of the rising edge of the first Y clock in the n-th column is set to the second coordinate in the first column.
Y coordinate of rising edge of Y clock Vy1 + Vy2
If the synchronous reference positions Vy1 + Vy2 -Dy, which are one before the above, are arranged at coordinates equal to or more than the above, it is clear that each synchronization reference position has one edge of a different type.

Conditional expression at this time Vy1 + Vy2-Dy = (n-1) * Dy Vy1 = X1 * Dy, Vy2 = X2 * Dy, N = X1 +
From X2, the number of columns of Y clocks becomes n = N. Therefore, if the Y clock sequence is composed of N or more columns, at least one edge of different type can be arranged at each synchronization reference position.

As described above, if the period of the Y clock 1 is N, if at least N types of columns of Y clocks are used, at least one different edge is arranged at each synchronization reference position. Two sets of different types of edges always exist around each sampling line in the Y direction. Thus, at least N types of columns of Y
The clock, the sync pattern detecting means 9 for detecting the sync reference position, and the data sampling means 10 for calculating the sampling lines and the data sampling positions in the X and Y directions from the sync reference position continuously read the data part 3 without any gap. be able to.

FIG. 6 is a diagram showing a sample of the machine reading mark of FIG. 1 when the same print distortion as in FIG. 13 occurs. In FIG. 6, T1 to T6 correspond to those in FIG. 13, and although the same print distortion occurs, the length of the synchronization pattern in the sub-scanning direction of the recording device is set so that all the synchronization patterns do not disappear. Since it is twice as much as Dy1,
As described above, it is clear that the synchronization pattern does not disappear even when the data is read by using the reading device of FIG. 2, and the center position of the data pattern is sampled (S is a sampling line in the Y direction).

As described above, according to the first embodiment, Y
Black pattern length V of clock 1 mark in the sub-scanning direction
The relationship between y1 and the length Vy2 of the white pattern and the distance Dy between the data lines of the data part 3 is Vy1 is X1 * Dy,
Vy2 is X2 * Dy and X1 and X2 are integers of 2 or more, N
Is the sum of X1 and X2, and the Y clock 1 is composed of at least N types of columns, so that even if printing distortion occurs, the synchronization pattern does not disappear, and it is possible to read the position deviated from the center of the data line. Therefore, it is possible to reliably detect each sampling position.

The second embodiment will be described in detail below. FIG. 7 is a diagram showing the structure of a machine reading mark according to the second embodiment of the present invention. In FIG. 7, the machine reading marks include the Y clock 1 and the X clock 2 which are synchronization pattern areas, the data portion 3 which is a data pattern area, and the inclination detection line 4 which is a coordinate detection pattern area.
And the reference position detection mark 5.
Each area is composed of a black pattern having a low reflectance and a white pattern having a high reflectance.

In the data part 3, in order to express the data "10101010 ...", which is the data formed in the data part 3, by the black pattern and the white pattern, the black pattern is expressed by the bit "1". , White pattern bit "0"
Is expressed. The black-and-white patterns are arranged at intervals Dx in the main scanning direction of the marks, and this data arrangement is a data line. A plurality of data lines are arranged in the sub-scanning direction of the mark, and the data line interval of the mark in the sub-scanning direction at this time is Dy. Dx and Dy are values set by the recording density of the recording device and the resolution characteristic of the reading device.

The Y clock 1 is for designating a synchronous reference position of the mark in the sub-scanning direction, and is a plurality of columns in which black patterns and white patterns are periodically arranged in the sub-scanning direction of the mark. Are arranged in the main scanning direction, and the respective columns are arranged so as to be shifted in parallel by the data line interval Dy of the data portion 3 in the sub scanning direction of the marks.
The length Vy1 of the black pattern mark in the sub-scanning direction and the length Vy2 of the white pattern are determined by the data line interval D of the data section 3.
determined by y. The relationship is that Vy1 is X1 * D
y and Vy2 are X2 * Dy (X1 and X2 are integers of 2 or more)
And Vy1 and Vy2 are always equal (X1 = X2),
If the period in which the black pattern and the white pattern are arranged is N (the sum of X1 and X2), the number of columns of the Y clock is N / 2 (= X
1 = X2). In FIG. 7, X1 and X2 are 2,
The period N is 4 and the number of columns N / 2 is 2.

The length Vx1 of the marks of the black pattern and the white pattern in the main scanning direction and the length Vx2 between the columns of the marks of the Y clock 1 in the sub scanning direction are equal to Dx here, but are not less than Dx. It may be a value. Similar to the first embodiment, the X clock 2 is for designating the synchronous reference position of the mark in the main scanning direction, and the black pattern and the white pattern are periodically arranged in the main scanning direction of the mark. There is. The interval Hx1 between the center of the first X clock 26 and the center 29 of the second X clock in the main scanning direction of the mark and the interval Hx2 between the center 29 of the second X clock and the center of the third X clock 27 are the intervals between the data of the data section 3. It is determined by the distance Dx. The relationship is Hx1 = Hx2 = Dx. Here, the interval Hx0 in the main scanning direction between the first Y clock 18 and the first X clock 26 of the second column and the mark of the data section 3 is equal to Dx, but may be any value not less than Dx. Further, the length Hy of the mark of the X clock 2 in the sub-scanning direction and the interval Dy0 of the mark of the X clock 2 and the data part 3 in the sub-scanning direction are
It may be any value equal to y but not less than Dy.

As described above, the point different from the mark of the first embodiment is that when the Y clock cycle is N, the first embodiment is composed of N rows of Y clock rows. N
That is, it is composed of two Y clock trains, and the lengths Vy1 and Vy2 of the black pattern and the white pattern always have the same relationship.

With the above configuration, the data reference portion 3 can be read by detecting the synchronization reference position for reading the data portion 3 from the Y clock 1 and the X clock 2 (details will be described later).

FIG. 8 shows the machine reading mark of FIG. 8 and FIG.
FIG. 6 is a diagram illustrating an operation of a synchronization pattern detection means and a data sampling means in the reading device. In FIG. 8, the synchronization pattern detecting means 9 of FIG. 2 detects the edge coordinates which are the synchronization reference position of each black pattern on the edge search lines 8a and 8b parallel to the Y direction, and the data sampling means 10 causes the black pattern to be detected. From the edge coordinate of X direction, Y
The data sampling position is calculated from the directional sampling line. The details will be described below.

The first sampling line 39 in the Y direction is the rising edge coordinate 17 of the first Y clock 17 in the first column.
a is a line that is substantially parallel to the X direction and passes through the midpoint between the rising edge coordinates 18a of the first Y clock 18 of the second column and the Y direction second sampling line 40 is the rising edge of the first Y clock 18 of the second column. Edge coordinates 18a and first
Falling edge coordinates 17b of the first Y clock 17 in the column
It is a line that is substantially parallel to the X direction and passes through the midpoint between them.

Similarly, a sampling line in the Y direction parallel to the X direction passing through the midpoint between the rising edge coordinates (edge a) and the falling edge coordinates (edge b) of the black patterns of the adjacent Y clocks is calculated in the same manner. can do. As described above, the Y clock 1 is arranged so that there is always one set of edges around each sampling line in the Y direction.

On the other hand, the X direction first sampling line 31
Is a line substantially parallel to the Y direction passing through the center position 28 of the first X clock 26, and the second sampling line 32 in the X direction is a line substantially parallel to the Y direction passing through the midpoint position 29 of the second X clock. Similarly, the third sampling line 33 in the X direction and the fourth sampling line 3 in the X direction
4, the X-direction fifth sampling line 35, the X-direction sixth sampling line 36, and the X-direction seventh sampling line 37 can be obtained from the center positions of the respective X clocks.

As described above, by sampling the data sampling position 38a, which is the intersection of the Y-direction first sampling line 39 and the X-direction first sampling line 31, the data on the data line 38 can be read. . Hereinafter, similarly, the first sampling line 39 in the Y direction and the second sampling line 32 in the X direction
And a data sampling position 38b which is an intersection of the X direction third sampling line 33 and a data sampling position 38d which is an intersection of the X direction fourth sampling line 34.
And a data sampling position 38e which is an intersection with the X-direction fifth sampling line 35, a data sampling position 38f which is an intersection with the X-direction sixth sampling line 36, and an X-direction seventh sampling line 37. The black pattern and the white pattern of the data part 3 in FIG. 1 can be read as bits "1" and "0" by sampling the intersection with the data sampling position 38g.

As described above, the difference from the reading method of the first embodiment is that in order to calculate one sampling line in the Y direction, two edges of different types are used in the first embodiment. On the other hand, the same type of edge set is also used.

As described above, two columns of Y clocks, each column having a pattern of cycle 4, have been described. In general, in the case of cycle N, N / 2 or more rows of Y clocks are required. To do.

In order to read the data section 3, the data sampling means 10 calculates sampling lines in the X and Y directions from the synchronization reference position detected by the synchronization pattern detecting means 9. In the reading method of this embodiment, one set of edges is used regardless of the type in order to calculate one sampling line in the Y direction. Therefore, in order to calculate the sampling line in the Y direction continuously and without gaps. Is Y
There must always be a set of edges around the directional sampling line. For that purpose, the Y clock may be configured such that one edge exists at each synchronization reference position.

Here, the Y coordinate of the rising edge of the first Y clock in the first column is 0, the Y coordinate of the rising edge of the first Y clock in the second column is Dy, and the first coordinate in the third column is
If the Y coordinate of the rising edge of the Y clock is 2 * Dy, the Y of the rising edge of the first Y clock in the nth column
The coordinates are (n-1) * Dy. Similarly, the first in the first row
Since the Y coordinate of the falling edge of the Y clock is Vy1 which is the length of the black pattern, the Y coordinate of the falling edge of the first Y clock in the nth column is Vy1 + (n-1) * Dy.
Is. The Y coordinate of the falling edge of the first Y clock of the first column is Vy1, each column is shifted in parallel by an interval Dy in the Y direction, and the length Vy of the black pattern and the white pattern is Vy1.
Since 1 and Vy2 are equal and are integer multiples of Dy (X1 = X2), the Y coordinate (n-1) * Dy of the rising edge of the first Y clock of the nth column can be calculated from the first Y clock of the first column. It is obvious that one edge exists at each sync reference position if the sync reference position Vy1 -Dy, which is one position before the Y coordinate Vy1 of the falling edge, is arranged.

Conditional expression at this time: Vy1-Dy = (n-1) * Dy Vy1 = X1 * Dy, Vy2 = X2 * Dy, N = X1 +
From X2 and X1 = X2, the number of columns of Y clocks becomes n = N / 2. Therefore, N
If the Y clock sequence is composed of / 2 columns or more, at least one edge can be arranged at each synchronization reference position.

As described above, if the period of the Y clock 1 is N, and if the Y clocks of at least N / 2 types of columns are used, at least one edge is arranged at each synchronization reference position and each Y direction. Around the sampling line of
There will always be one set of edges. in this way,
The data part 3 can be read by the sync pattern detecting means 9 for detecting the sync reference position and the data sampling means 10 for calculating sampling lines and data sampling positions in the X and Y directions from the sync reference position.
In addition, since the length of the synchronization pattern in the sub-scanning direction of the recording device is twice as long as Dy1 so that all the synchronization patterns do not disappear, the synchronization pattern does not disappear even if the reading device of FIG. 2 is used for reading. Instead, the center position of the data pattern can be sampled by detecting the edges of the synchronization patterns in different columns.

According to the second embodiment, the relationship between the length Vy1 of the black pattern and the length Vy2 of the white pattern in the sub-scanning direction of the mark of Y clock 1 and the distance Dy between the data lines of the data section 3 is obtained. , Vy1 is X1 * Dy, Vy2 is X2 *
Dy and X1 and X2 are integers of 2 or more, X1 and X2 are equal, and N is the sum of X1 and X2.
In addition to the effect that each of the sampling positions can be detected without fail even if a print distortion occurs, by configuring with / 2 or more columns, Y of N / 2 columns Since it can be realized by a clock, when the machine reading mark is printed on the same area, the synchronization pattern area can be halved compared to the first embodiment, so that a large data area should be secured accordingly. You can

FIG. 9 is a diagram showing the structure of a machine reading mark according to the third embodiment of the present invention. In FIG.
The machine reading marks are the four rows of Y that are the synchronization pattern area.
Clock 1 and 4 rows of auxiliary Y clocks 51 and 1 row of X clocks 2, a data portion 3 which is a data pattern area, a tilt detection line 4 which is a coordinate detection pattern area, and a reference position detection mark 5. There is. The difference from the machine reading mark of FIG. 1 is that the sync pattern areas are provided on both sides of the data part 3 and, as described in FIG.
Of the auxiliary Y clock 51
Can independently detect the synchronization reference position in the Y direction. As a result, since the sampling line in the Y direction can be calculated from the synchronization reference position detected from the Y clock 1 and the synchronization reference position detected from the auxiliary Y clock 51, the synchronization pattern disappears even if print distortion occurs. In addition to the effect that each sampling position can be reliably detected, the reading operation according to the inclination is performed for each data line, and the reading operation is performed with the same inclination for all lines based on the mark inclination signal 12. It is possible to reduce the reading error due to the inclination as compared with the method of performing.

FIG. 10 is a diagram showing the structure of a machine reading mark according to the fourth embodiment of the present invention. In FIG. 10, the machine reading marks include four rows of Y clocks 1 and four rows of X clocks 52 which are synchronous pattern areas, a data portion 3 which is a data pattern area, and a tilt detection line 4 which is a coordinate detection pattern area. It is composed of the reference position detection mark 5. The difference from the machine reading mark of FIG. 1 is that the X clock 2 of FIG. 1 is replaced with an X clock 52 of four columns. As described with reference to FIG. 5, the sampling lines in the X direction are calculated from the four columns of the X clocks 52 in the same manner as the method of calculating the sampling lines in the Y direction from the Y clock 1 to determine the main scanning direction and the sub-direction of the mark. With respect to the two directions of the scanning direction, even if the printing distortion occurs in the recording device, the synchronization pattern does not disappear and each sampling position can be reliably detected.

In the first, second, third and fourth embodiments, the rectangular black pattern has been described as the synchronizing pattern, but the same effect can be obtained even in the shape having at least two sides in the same direction. To be

Further, in the first and second embodiments, one type of Y clock sequence is described as one column, but the present invention is not limited to this, and the same type of Y clock sequence is configured as a plurality of sequences. Good.

In the first embodiment, the length Vy1 (= X1 * Dy) of the black pattern and the length Vy2 of the white pattern are set.
Although the case where (= X2 * Dy) is equal (X1 = X2) has been described, the same effect can be obtained for X1 ≠ X2 as long as X1 and X2 are integers of 2 or more.

In the second embodiment, the length Vy1 (= X1 * Dy) of the black pattern and the length Vy2 of the white pattern are set.
(= X2 * Dy) has been described in the case of X1 = X2 = 2, but not limited to this, if X1 and X2 are equal, the same effect can be obtained when X1 and X2 are integers of 2 or more.

In the first, second, third and fourth embodiments, the Y clocks shifted by Dy in parallel with the sub-scanning direction of the mark have been described, but the order is not limited to this and other clocks may be used. Even if they are arranged in order, the same effect can be obtained.

Further, in the first, second, third and fourth embodiments, the sync pattern area is arranged around the data area, but the present invention is not limited to this, and the sync pattern area may be arranged in the data area. The same effect can be obtained.

[0069]

As described above, according to the present invention, the data pattern region formed by arranging the data pattern rows arranged in the first direction at the interval Dy in the second direction perpendicular to the first direction. And a second black pattern having two types of synchronization reference sides
The length of X1 * Dy (X1 is an integer of 2 or more) and the length of the white pattern is X2 * Dy (X2 is an integer of 2 or more). Of at least N types (N is X
Machine reading in which a data pattern is arranged at a midpoint between different sync reference sides of different types adjacent to each other at an interval Dy. Data for sampling the data pattern by calculating the midpoint between different sync reference positions of adjacent types at the interval Dy by using the mark By providing the sampling means, with a simple structure, the influence of print distortion caused by mechanical or electrical factors of the recording apparatus is reduced, the sync pattern is not lost, and the position shifted from the center of the data line is read. Without fail, it is possible to provide a highly reliable machine reading mark and its reading device that can perform accurate sampling.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a machine reading mark that is a first embodiment of the present invention.

FIG. 2 is a diagram showing the configuration of a reading device that is an embodiment of the present invention.

3 is a diagram showing an image after the mechanical reading mark of FIG. 1 is read by the reading device of FIG.

FIG. 4 is a diagram showing an image after tilt correction.

5A and 5B are views showing the operation of the mechanical reading mark of FIG. 1 and the synchronization pattern detecting means and the data sampling means in the reading device of FIG.

FIG. 6 is a view showing a sample when print distortion occurs in the machine reading mark of FIG.

FIG. 7 is a diagram showing a configuration of a machine reading mark that is a second embodiment of the present invention.

FIG. 8 is a diagram showing an explanation of the operation of the mechanical reading mark of FIG. 7 and the synchronization pattern detecting means and data sampling means in the reading device of FIG.

FIG. 9 is a diagram showing the configuration of a machine reading mark that is a third embodiment of the present invention.

FIG. 10 is a diagram showing the configuration of a machine reading mark that is a fourth embodiment of the present invention.

FIG. 11 is a view showing a machine reading mark which is a first conventional example.

FIG. 12 is a diagram showing the operation of the mechanical reading mark of FIG. 11 and the synchronization pattern detecting means and data sampling means in the reading device of FIG. 2;

FIG. 13 is a view showing a print sample when print distortion occurs in the machine reading mark of FIG. 11.

14 is a diagram showing an output waveform after the synchronization pattern of FIG. 13 is read by the reading device of FIG.

FIG. 15 is a view showing a machine reading mark which is a second conventional example.

16 is a view showing a sample in the case where print distortion occurs in the machine reading mark of FIG.

[Explanation of symbols]

 1 Y clock 2 X clock 3 Data part 4 Tilt detection line 5 Reference position detection mark 6 Image input means 7 Tilt detection means 8 Reference position detection means 9 Sync pattern detection means 10 Data sampling means 11 Image 12 Mark tilt signal 13 Reference position Coordinates 14 Position coordinates of synchronization pattern

Claims (8)

[Claims] 1. A plurality of data pattern rows formed by arranging a plurality of data patterns in which data is encoded in a first direction are arranged at a predetermined interval L in a second direction perpendicular to the first direction. And the data pattern area formed in parallel with the first direction are arranged one on each side of the synchronization pattern, and the position of the synchronization reference side in the second direction is set as the synchronization reference position. The synchronization reference side on the leading edge side with respect to the direction 2 is the first synchronization reference side, and the synchronization reference side on the trailing edge side with respect to the second direction is the second synchronization reference side. The distance between the reference sides is X times L (X is an integer of 2 or more), and the synchronization pattern sequence is Y times L of the synchronization pattern in the second direction (Y is an integer of 2 or more) blank. And a plurality of parts are arranged at equal intervals N times L (N is the sum of X and Y). A synchronization pattern region formed by arranging in the first direction at least N kinds of columns formed by arranging the synchronization pattern columns in parallel in the second direction by a distance L, and the first direction or the second direction. And a coordinate detection pattern area formed by arranging a reference position detection pattern for indicating a reference position and a reference position detection pattern for indicating a reference position. A machine-readable mark arranged at a midpoint between the synchronization reference positions adjacent to each other. 2. The machine reading mark according to claim 1, wherein the distance between the sync reference sides on both sides of the sync pattern is equal to the length of the blank portion provided between the sync patterns in the second direction. 3. A plurality of data pattern rows formed by arranging a plurality of data patterns in which data is encoded in a first direction are arranged at a predetermined interval L in a second direction perpendicular to the first direction. And the data pattern area formed in parallel with the first direction are arranged one on each side of the synchronization pattern, and the position of the synchronization reference side in the second direction is set as the synchronization reference position. The synchronization reference side on the leading edge side with respect to the direction 2 is the first synchronization reference side, and the synchronization reference side on the trailing edge side with respect to the second direction is the second synchronization reference side. The distance between the reference sides is X times L (X is an integer of 2 or more), and the synchronization pattern is
In a direction X, a blank portion X times L is provided, and a plurality of blank portions are arranged at equal intervals 2X times L.
The sync pattern areas formed by arranging in the first direction in the X rows that are displaced in parallel by the distance L in the direction, the tilt detection pattern that defines the first direction or the second direction, and the reference position are indicated. A coordinate detection pattern area formed by arranging reference position detection patterns, and arranging the position of each of the data pattern rows in the second direction at a midpoint between the synchronization reference positions adjacent to each other at an interval L. Machine reading mark characterized by. 4. The machine reading mark according to claim 1, wherein the sync pattern areas are arranged on both sides of the data pattern area in the first direction. 5. A plurality of data pattern strings formed by arranging a plurality of data patterns in which data is encoded at a predetermined interval M in a first direction are provided in a second direction perpendicular to the first direction. The data pattern areas formed by being arranged at intervals L and the synchronization reference sides parallel to the second direction are arranged one on each side of the synchronization pattern, and the position of the synchronization reference side in the first direction is set to the first synchronization. With the reference position, the synchronization reference side on the leading edge side with respect to the first direction of the synchronization pattern is the first synchronization reference side, and the synchronization reference side on the trailing edge side with respect to the first direction is the second synchronization reference side. Assuming that the distance between the synchronization reference sides on both sides of the synchronization pattern is X1 times M (X1 is an integer greater than or equal to 2), the synchronization pattern sequence is the same as Y1 times M (Y1 times M1 in the first direction). Is an integer greater than or equal to 2) and a blank part is provided, and N1 times M (N1 is X1 (Sum of 1) is formed at equal intervals, and the synchronization pattern row is formed by arranging in the second direction by at least N1 kinds of rows that are shifted in parallel by a distance M in the first direction. The first synchronization pattern area and the synchronization reference sides parallel to the first direction are arranged one on each side of the synchronization pattern, and the position of the synchronization reference side in the second direction is set as the second synchronization reference position. The synchronization pattern has the synchronization reference side on the leading edge side with respect to the second direction of the pattern as the first synchronization reference side and the synchronization reference side on the trailing edge side with respect to the second direction as the second synchronization reference side. The distance between the synchronization reference sides on both sides is X2 times L (X2 is an integer of 2 or more), and the synchronization pattern sequence is Y2 times L of L in the second direction (Y2 is an integer of 2 or more). ), And a plurality of them at equal intervals of N2 times L (N2 is the sum of X2 and Y2). A second synchronization pattern area formed by arranging the individual synchronization pattern rows in the first direction and arranging the synchronization pattern rows in the first direction by at least N2 types of rows that are parallelly displaced by a distance L in the second direction; A tilt detection pattern defining one direction or a second direction and a coordinate detection pattern area formed by arranging a reference position detection pattern indicating a reference position, and a first direction of each data pattern row. The position of
It is arranged at the midpoint between the first synchronization reference positions adjacent to each other at the interval M, and the position of each data pattern row in the second direction is set to the midpoint between the second synchronization reference positions adjacent to each other at the interval L. Machine readable mark characterized by being placed. 6. An image input means for reading the image of the machine reading mark according to claim 1 or 2 and outputting image data, and a main scan of the image input means based on the image data output by the image input means. Direction or a sub-scanning direction, an inclination detecting means for detecting an angle formed by the inclination detecting pattern to detect the first or second direction, and a reference position for detecting coordinates of a reference position detecting pattern indicating a reference position. The synchronization pattern is detected from the image data using the detection means, the inclination detection means, and the first or second direction and coordinates detected by the reference position detection means, and the first synchronization reference edge is detected. Alternatively, the sync pattern detecting means for detecting the second sync reference side and the sync reference position detected by the sync pattern detecting means are adjacent to each other. A data sampling means for reading a data pattern by setting a data pattern reading reference position at a midpoint of a position in the second direction between the first synchronization reference side and the second synchronization reference side which are in contact with each other. Reading device. 7. The data sampling means is characterized in that the synchronization reference position detected by the synchronization pattern detecting means is the second between the plurality of pairs of the synchronization reference edges of the first synchronization reference edge and the second synchronization reference edge which are adjacent to each other. 5. The reading device for reading a machine reading mark according to claim 4, wherein the data pattern reading reference position is set to the average of the midpoints of the two directions to read the data pattern. 8. An image input means for reading the image of the machine reading mark according to claim 3 and outputting image data, and a main scanning direction or a sub-scan of the image input means based on the image data output by the image input means. The first angle is detected by detecting an angle formed by the inclination detection pattern with respect to a direction.
Alternatively, a tilt detecting unit that detects a second direction, a reference position detecting unit that detects coordinates of a reference position detecting pattern that indicates a reference position, the tilt detecting unit, and the first position detected by the reference position detecting unit. Alternatively, a synchronization pattern detecting unit that detects the synchronization pattern from the image data by using the second direction and coordinates and detects the first synchronization reference side or the second synchronization reference side of the synchronization reference side,
A reading including a data sampling means for reading a data pattern by setting a data pattern reading reference position at the midpoint of the second direction of the synchronization reference side adjacent to the synchronization reference position detected by the synchronization pattern detecting means. apparatus.