JPH10190989A - Scanner with sub-scanning magnification correction function - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform application additionally to a one-dimensional CCD by performing the magnification correction of a sub-scanning direction in the case that the sub-scanning magnification of the printed result of scanning an original is different as compared to the original sub-scanning magnification of the original. SOLUTION: A traveling part 1 carries an original in the direction of an arrow A at a fixed speed, and the CCD 3 is controlled by the storage time signals (a) with a fixed cycle inputted from a CCD drive part 2, scans the original and outputs the result as scanned image information (b.) The scanned image information (b) is converted into digital multi-valued data and sent out to a binarization part 5 as the digital multi-valued data. Binary data (d) in the form of scanned data binarized in the binarization part 5 are printed at a printing part 6. Then, the printed result to the printing part 6 and the original are visually compared or with a scale, and in the case that the sub-scanning magnifications are different, the cycle of the storage time signals (a) outputted by the CCD drive part 2 is varied manually.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scanner with a sub-scanning magnification correction function, and more particularly to a scanner with a sub-scanning magnification correction function having a sub-scanning direction magnification correction function in a scanner used in a copying apparatus or a facsimile machine.

[0002]

2. Description of the Related Art Conventionally, various methods for realizing a magnification correction function in the sub-scanning direction of a scanner have been proposed and put into practical use.

The first prior art is disclosed in
Japanese Patent No. 254961 discloses a “multifunctional projection magnification measuring device”.

In this method, digital multi-valued information is corrected by simple interpolation or simple thinning so as to match a magnification.

More specifically, the image of the transparent document inserted into the optical system is enlarged and reduced by the projection magnification measuring means so as to match the image on the projection surface. Is measured, and auxiliary data indicating the relationship between the original to be color-separated by the scanner or the layout designation sheet and the transparent original or the image placed on the projection surface is input from the auxiliary data input means. Magnification data correction means corrects the magnification data of the transparent document obtained by the projection magnification measurement means based on the data inputted from the auxiliary data input means, and outputs the corrected data from the correction data output means. Is done.

Further, as the transparent original, a secondary original obtained by enlarging or reducing a primary original, an original to be subjected to color separation by a scanner, a graphic original representing a graphic drawn on a designated layout sheet, or the like is used. Assignment designation paper, secondary assignment designation paper obtained by enlarging or reducing this assignment designation paper, or a document that is color-separated by a scanner is used to represent the image on the projection plane, and is used as the auxiliary data input means. A magnification / reduction ratio inputting unit for inputting a magnification / reduction ratio of the secondary document or the secondary layout designation sheet is applied, and magnification data obtained by the projection magnification measuring unit is corrected and corrected by a magnification correcting unit. The output data is output from the correction data output means.

As a second prior art, Japanese Patent Laid-Open No.
No. 212860, “Copier having magnification correction function”
There is.

This is a method of correcting the magnification in the sub-scanning direction by changing the traveling speed.

More specifically, in a copying machine for performing variable-magnification copying by setting the position of a lens disposed between a document and a photosensitive member and the moving speed of a scanner based on a correction value, a process from the document to the photosensitive member is performed. An image sensor disposed at the position of the distance and the conjugate length of the image sensor, means for measuring the actual magnification at that time by comparing the length of image information read by the image sensor with a predetermined reference length, Means for calculating a correction value for the lens position and the moving speed of the scanner from the obtained magnification.

Thus, the correction value of the moving speed of the scanner and the correction value of the position of the lens are automatically obtained from the image information read by the image sensor. Correction work becomes easy, and wasteful use of toner, paper and the like can be prevented. Further, since a correction value is automatically obtained from the image information read by the image sensor, an accurate correction can be performed by preventing occurrence of a mistake.

A third prior art is disclosed in
There is an "image reading apparatus" in Japanese Patent No. 22527.

This is applied to a photoelectric conversion device such as a photocoupler capable of independently changing a scanning cycle and an exposure timing cycle.

More specifically, a light source for illuminating a document to be read moving at a predetermined speed, an optical system for imaging reflected light or transmitted light from the document, and an image formed by the optical system for a predetermined period An image reading apparatus comprising: a light detecting element for scanning and converting the electric signal into an electric signal; and an exposure timing control oscillator for supplying an exposure timing signal having a predetermined period to the light detecting element. Error measuring means for measuring an error in the image reading magnification caused by variations in the image magnification and the original moving speed; and changing a scanning cycle of the photodetector in accordance with a measurement result of the error caused by the variation in the imaging magnification. A scanning cycle variable means for changing the cycle of the exposure timing signal according to a measurement result of an error caused by the variation of the document moving speed. Or an error measuring means for measuring an error in image reading magnification caused by a variation in the imaging magnification and the original moving speed of the optical system, and a measurement result of the error caused by the variation in the imaging magnification Scanning period variable means for changing the scanning period of the light sensing element, and a document moving speed variable means for changing the document moving speed according to the measurement result of the error caused by the variation of the document moving speed. Have.

Thus, in the former, a magnification error in the main scanning direction due to a variation in the imaging magnification of the optical system can be corrected by changing the scanning cycle of the photodetector, while the original moving speed is reduced. The magnification error caused by the variation is corrected by changing the cycle of the exposure timing of the photodetector.

In the latter case, magnification errors in the main scanning direction caused by variations in the imaging magnification of the optical system can be corrected by changing the scanning cycle of the photodetector, while variations in the original moving speed can be corrected. The resulting magnification error is corrected by adjusting the document moving speed.

[0016]

The "multifunctional projection magnification measuring apparatus" disclosed in Japanese Patent Laid-Open No. 01-254961, which is the first prior art, has a drawback that a memory is required when correcting the enlargement direction. Had. In addition, this method has a disadvantage that the resolution in the sub-scanning direction is deteriorated in the corrected line.

A second prior art of the prior art is disclosed in
In the "copying machine having a magnification correcting function" disclosed in Japanese Patent Application Laid-Open No. 2-212860, it cannot be realized with a simple stepping motor.
A C motor is required, which has the disadvantage of increasing costs.

Further, Japanese Patent Laid-Open No. 05-2, which is a third prior art, which aims at magnification correction by a method of varying the accumulation time.
The "image reading apparatus" disclosed in Japanese Patent No. 2527 can be applied to a photoelectric conversion device such as a photocoupler in which a scanning cycle and an exposure timing cycle can be independently changed, but the scanning cycle and the exposure timing cycle are structurally identical signals. However, it has a drawback that it cannot be applied to a one-dimensional CCD that must be used.

[0019]

A scanner with a sub-scanning magnification correction function according to the present invention is a scanner with a magnification correction function in the sub-scanning direction. When there is a difference in comparison with the scanning magnification, magnification correction in the sub-scanning direction is performed by varying a CCD accumulation time output by a CCD driving unit that drives a CCD which is a one-dimensional photoelectric conversion device according to the difference. I do.

A scanner with a sub-scanning magnification correcting function according to the present invention, in a scanner with a sub-scanning direction magnification correcting function, scans a pattern for magnification correction with high sub-scanning magnification accuracy before scanning a document. If the sub-scanning magnification of the scanned result is different from the previously known sub-scanning magnification of the pattern, a CCD driving unit that drives a CCD, which is a one-dimensional photoelectric conversion device, according to the difference, The magnification correction in the sub-scanning direction is performed by automatically changing the CCD accumulation time to be output, and then the original is scanned.

A scanner with a sub-scanning magnification correction function according to the present invention is a scanner with a magnification correction function in the sub-scanning direction, which scans a document with a magnification correction pattern with high sub-scanning magnification accuracy before scanning a document. And if the sub-scanning magnification of the first scan result is different from the previously-known sub-scanning magnification of the pattern before the return second scan, The magnification correction in the sub-scanning direction is performed by automatically varying the CCD accumulation time output by a CCD driving unit that drives a CCD that is a one-dimensional photoelectric conversion device, and the second CCD accumulation time is calculated based on the corrected CCD accumulation time. The original is scanned.

A scanner with a sub-scanning magnification correcting function according to the present invention has a traveling section for scanning and transporting a document at a constant constant speed when scanning one page, and the traveling section scans and transports the document. A CCD drive unit that outputs a CCD storage time signal of a fixed period during the scanning, and the document is controlled by the CCD storage time signal from the CCD drive unit while the traveling unit scans and transports the document. And a CCD as a one-dimensional photoelectric conversion device for converting the scanned optical signal into an analog signal and outputting a scanned image information signal, and converting the scanned image information signal from the CCD into digital multi-valued data. An A / D converter as analog / digital conversion means for converting and outputting digital multi-valued scan data; 2 a barrel multi-level scan data of the black-and-white
2 for binarizing the value signal and outputting binarized scan data
A digitizing unit; and a printing unit that prints the binarized scan data from the binarizing unit.

A scanner with a sub-scanning magnification correction function according to the present invention scans a document or a predetermined pattern for magnification correction with high sub-scanning magnification accuracy at a constant constant speed when scanning within one page. A traveling section for transporting, and while the traveling section scans and transports the document or the pattern, outputs a CCD accumulation time signal having a constant cycle and is controlled by a correction signal to vary the cycle of the CCD accumulation time signal. A CCD driving unit, and scanning the document or the pattern while the traveling unit scans and conveys the document or the pattern under the control of the CCD accumulation time signal from the CCD driving unit; A CCD as a one-dimensional photoelectric conversion device that converts a signal into an analog signal and outputs a scan image information signal,
AD as analog / digital conversion means for converting the scan image information signal from the CCD into digital multi-valued data and outputting digital multi-valued scan data
And the digital multi-level scan data from the AD converter is binarized into a black-and-white binary signal.
A binarizing unit that outputs binarized scan data, a memory that stores binarized binarized reference pattern data of the pattern in advance, and the binarized scan data from the binarizing unit. If there is a difference in each sub-scanning magnification by comparing the binary reference pattern data from the memory with each other, the correction signal for correcting the sub-scanning magnification is output and supplied to the CCD driving unit. And a comparing unit.

In the scanner with a sub-scanning magnification correcting function according to the present invention, the scanner for scanning the original or the pattern is a flatbed scanner, and the magnification in the sub-scanning direction is corrected every time the flatbed scanner scans each page. Then, the aging of the sub-scanning magnification error is also corrected.

[0025]

Next, the present invention will be described with reference to the drawings.

Referring to FIG. 1 showing the first embodiment of the present invention, a scanner with a sub-scanning magnification correcting function is not shown at a constant speed when scanning one page. , A CCD driving unit 2 that outputs a CCD accumulation time signal a of a fixed period while the traveling unit 1 scans and conveys a document, and a CCD accumulation time signal a from the CCD driving unit 2. While the traveling unit 1 scans and conveys the original, the original is scanned, and the scanned optical signal is converted to analog scan image information b and output as a CCD (Charge).
Coupled Device) 3, an AD converter 4 as an analog / digital converter for converting scan image information b from the CCD 3 into digital multi-valued data and outputting digital multi-valued data c, and a digital converter from the AD converter 4 Value data c 2 for binary signal of black and white
The binarizing unit 5 outputs the binarized data d by binarization, and the printing unit 6 that prints the binarized data d from the binarizing unit 5, that is, the binarized scan data.

More specifically, FIG. 1 shows a block configuration of a main part of a scanner with a sub-scanning magnification correcting function according to a first embodiment of the present invention.

In this configuration, the traveling section 1 conveys a document (not shown) at a constant speed in the direction of arrow A. Here, when the scanner is a flatbed scanner, an optical system may be conveyed instead of a document.

The CCD 3 scans the original while being controlled by the constant period accumulation time signal a input from the CCD drive unit 2 while the traveling system is transporting the original, and the result is used as scan image information b. Output.

The scanned image information b output by the CCD 3 is A
The data is converted into digital multi-value data by the D converter 4,
The data is sent to the binarization unit 5 as digital multi-value data c. The printing unit 6 prints the binarized data d as the scan data binarized by the binarizing unit 5.

The operator compares the result of printing on the printing unit 6 with the original visually or on a scale. If there is a difference in the sub-scanning magnification, the operator changes the cycle of the accumulation time signal a output from the CCD driving unit 2. Change manually.

Next, magnification correction in the sub-scanning direction will be described with reference to the timing chart of FIG.

The two signals in FIG. 2 are a motor drive signal e before magnification correction and an accumulation time signal a-1 before magnification correction.
Represents the relationship with Here, the cycle of the accumulation time signal a-1 before the magnification correction and the cycle of the motor drive signal e are made to match.

If the magnification before magnification correction is enlarged in the sub-scanning direction, the accumulation time signal a-
As shown in 2, the period is made longer according to the magnification. Also, if the magnification was reduced in the sub-scanning direction before the magnification correction,
The cycle of the accumulation time is shortened in accordance with the reduction ratio as in the accumulation time signal a-3 after the magnification correction at the time of reduction. This enables magnification correction in the sub-scanning direction.

This will be specifically described below.

Assuming that the accumulation time period of the CCD 3 is T and the traveling speed of the traveling unit 1 is V, the length per line at the time of scanning is represented by V × T.

When the original image can be composed of n lines, the sub-scanning length X1 of the printing result is as follows: X1 = V × T × n Assuming that the length of the sub-scanning of the document is X2, the magnification error α in the sub-scanning can be expressed as α = X1 ÷ X2.

Therefore, the magnification correction in the sub-scan is performed by changing the accumulation time of the CCD 3 from T to T × (X1 ÷ X2).

This makes it possible to correct the magnification in the sub-scanning direction.

Next, a second embodiment of the present invention will be described with reference to FIG.

Referring to the block diagram of FIG. 3 showing the second embodiment of the present invention, a scanner with a sub-scanning magnification correction function is illustrated at a constant constant speed when scanning within one page. A traveling unit 1 for scanning and transporting a predetermined pattern 7 for magnification correction attached to an original or a scanning surface which is not scanned, and a CCD having a constant period while the traveling unit 1 scans and transports the original or pattern 7 The CCD driving unit 2 which outputs the accumulation time signal a and is controlled by the correction signal g to vary the cycle of the accumulation time signal a, and the traveling unit 1 is controlled by the CCD accumulation time signal a from the CCD driving unit 2 to move the original. Alternatively, an image sensor that scans the original or the pattern 7 while scanning and transporting the pattern 7, converts the scanned optical signal into analog scan image information b, and outputs the analog image information b. CCD3, an AD converter 4 as an analog / digital converter for converting scan image information b from the CCD3 into digital multivalued data and outputting digital multivalued data c, and digital multivalued data from the AD converter 4 a binarizing unit 5 that binarizes c into a black-and-white binary signal and outputs binarized data d;
And the binary data d from the binarization unit 5 and the binary data f from the memory 8 are compared to each other to scan each sub-scan. When there is a difference in magnification, the comparison unit 9 outputs a correction signal g for correcting the sub-scanning magnification and supplies the signal to the CCD driving unit 2.

More specifically, FIG. 3 is a block diagram showing a main part of a scanner with a sub-scanning magnification correcting function according to a second embodiment of the present invention.

In this configuration, the traveling section 1 conveys the pattern 7 stuck on the scan surface at a constant speed in the direction of arrow A. Here, when the scanner is a flatbed scanner, an optical system may be conveyed instead of the original or the pattern 7.

The CCD 3 scans the original while being controlled by the constant period accumulation time signal a input from the CCD driving section 2 while the traveling system is transporting the pattern 7, and scans the scanned image information b Output as

The scan image information b output by the CCD 3 is A
The data is converted into digital multi-value data by the D converter 4,
The data is sent to the binarization unit 5 as digital multi-value data c. The comparing unit 9 compares the binarized data d as the scan data binarized by the binarizing unit 5 with the binarized data f of the pattern 7 stored in the memory 8 in advance, and compares the If there is a difference in the scanning magnification, a correction signal g is output and supplied to the CCD driver 2, and the period of the accumulation time signal a output from the CCD driver 2 is automatically varied.

As described above, in the second embodiment,
A pattern with high magnification accuracy, that is, a pattern 7 for magnification correction is pasted on the scan surface, scanning is performed, and magnification correction is performed by comparing the scan data with pattern data stored in advance.

Next, a specific magnification correction in the sub-scanning direction according to the second embodiment will be described.

Assuming that the accumulation time period of the CCD 3 is T and the traveling speed of the traveling unit 1 is V, the length per line at the time of scanning is represented by V × T.

When the image of the pattern 7 is composed of n lines, the length X3 of the sub-scan as a result of the binarization is expressed as follows: X3 = V × T × n Assuming that the length of the sub-scan of the pattern 7 is X4, the magnification error β of the sub-scan can be expressed as β = 3 ÷ X4.

Therefore, magnification correction in the sub-scan is performed by changing the accumulation time of the CCD 3 from T to T × (X2 ÷ X4).

This makes it possible to correct magnification in the sub-scanning direction.

Next, a third embodiment of the present invention is a case where the scanner in the above-described second embodiment is limited to a flatbed scanner which requires a prescan.
Other configurations are the same as those of the second embodiment.

That is, in the case of the flatbed scanner, the pattern 7 is scanned in the pre-scan, and the original is scanned in the return scan. That is, magnification correction in the sub-scanning direction is performed during pre-scanning, and the original is scanned based on the corrected CCD accumulation time.

Therefore, this magnification correction is performed for each scan.
That is, since the scanning is performed for each page, it is possible to correct the secular change of the sub-scanning magnification error.

[0055]

As described above, according to the present invention, the cycle of the CCD accumulation time signal output from the CCD driving unit is varied when the sub-scanning magnification of the print result is different from the sub-scanning magnification of the document. Thus, magnification correction in the sub-scanning direction can be performed.

A predetermined pattern having a high sub-scanning magnification accuracy is scanned, and when the sub-scanning magnification of the scanned result is different from the sub-scanning magnification of the pattern which is known in advance, the output of the CCD driving unit is output. The magnification correction in the sub-scanning direction can be performed by changing the cycle of the CCD accumulation time signal.

Further, when a pattern having a high sub-scanning magnification accuracy is pre-scanned, and the sub-scanning magnification as a result of the pre-scanning is different from the sub-scanning magnification of the pattern which is known in advance, the CCD output by the CCD driving unit is output. By changing the cycle of the accumulation time signal, magnification correction in the sub-scanning direction is performed in advance, and the original can be scanned at the cycle of the CCD accumulation time signal after the magnification correction. As a result, aging of the sub-scanning magnification error can be corrected.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a main part of a scanner with a sub-scanning magnification correction function according to a first embodiment of the present invention.

FIG. 2 is a waveform chart for explaining magnification correction of the scanner with a sub-scanning magnification correction function of the embodiment.

FIG. 3 is a block diagram illustrating a main part of a scanner with a sub-scanning magnification correction function according to a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Running part 2 CCD drive part 3 CCD 4 A / D converter 5 Binarization part 6 Printing part 7 Pattern 8 Memory 9 Comparison part a CCD accumulation time signal a-1 Storage time signal before magnification correction a-2 After magnification correction at magnification Accumulation time signal a-3 accumulation time signal after magnification correction at reduction b scan image information c digital multi-valued data d binarized data e motor drive signal f binarized data g correction signal

Claims (6)

[Claims] In a scanner with a magnification correction function in the sub-scanning direction, if a sub-scanning magnification of a print result obtained by scanning an original is different from an original sub-scanning magnification of the original, the scanner responds to the difference. A magnification correction in the sub-scanning direction by varying a CCD accumulation time outputted by a CCD driving unit for driving a CCD which is a one-dimensional photoelectric conversion device. 2. A scanner with a magnification correction function in the sub-scanning direction, wherein a pattern for magnification correction with high sub-scanning magnification accuracy is scanned prior to scanning of an original, and the sub-scanning magnification as a result of the scanning is obtained. If there is a difference compared with the previously known sub-scanning magnification of the pattern, a CCD that drives a CCD that is a one-dimensional photoelectric conversion device according to the difference
A scanner with a sub-scanning magnification correcting function, wherein the magnification of the sub-scanning direction is corrected by automatically changing a CCD accumulation time outputted by a driving unit, and then the original is scanned. 3. A scanner having a magnification correction function in the sub-scanning direction, wherein a first scan is performed before a pattern for magnification correction having high sub-scanning magnification accuracy is scanned on a document, and a second return is performed. If the sub-scanning magnification of the first scan result is different from the previously-known sub-scanning magnification of the pattern before scanning, if the sub-scanning magnification of the pattern is different, CCD which is a one-dimensional photoelectric conversion device is used in accordance with the difference. The magnification correction in the sub-scanning direction is performed by automatically varying the CCD accumulation time output by the CCD driving unit that drives the CCD.
A scanner with a sub-scanning magnification correction function, wherein scanning is performed with the original as the second scan according to a CD accumulation time. 4. A traveling section for scanning and transporting a document at a constant constant speed when scanning within one page, and a CCD accumulation time of a constant cycle while the traveling section scans and transports the document. A CCD driving unit that outputs a signal, and scanning the original while the traveling unit scans and conveys the original under the control of the CCD accumulation time signal from the CCD driving unit. A CCD as a one-dimensional photoelectric conversion device for converting a scan image information signal into an analog signal and outputting a scan image information signal; and converting the scan image information signal from the CCD into digital multi-value data and outputting digital multi-value scan data An AD converter as analog / digital conversion means for converting the digital multi-valued scan data from the AD converter into a black-and-white binary signal. 2. The sub-scan according to claim 1, further comprising: a binarization unit configured to output the binarized scan data from the binarization unit; and a printing unit configured to print the binarized scan data from the binarization unit. 3. Scanner with magnification correction function. 5. A scanning section for scanning and transporting a document or a predetermined pattern for magnification correction with high sub-scanning magnification accuracy at a constant constant speed when scanning within one page; A CCD driving unit that outputs a CCD accumulation time signal of a fixed period while scanning and transporting the document or the pattern and that is controlled by a correction signal to vary the period of the CCD accumulation time signal; The scanning unit scans the original or the pattern while the traveling unit scans and transports the original or the pattern under the control of the CCD accumulation time signal, and converts the scanned optical signal into an analog signal to scan the image. A CCD as a one-dimensional photoelectric conversion device for outputting an information signal; and a digital multi-valued data converting the scanned image information signal from the CCD. As analog / digital conversion means for converting digital data into digital multi-valued scan data.
A binarization unit for binarizing the digital multi-level scan data from the AD converter into a black-and-white binary signal and outputting binarized scan data; and a binarized binarization of the pattern. A memory in which reference pattern data is stored in advance; and a comparison between the binary scan data from the binarization unit and the binary reference pattern data from the memory. 4. The sub-scanning magnification correcting function according to claim 2, further comprising: a comparing unit that outputs the correction signal for correcting the sub-scanning magnification and supplies the correction signal to the CCD driving unit when there is a sub-scanning magnification. Attached scanner. 6. A scanner for scanning the original or the pattern is a flatbed scanner, and performs magnification correction in the sub-scanning direction for each scan of each page of the flatbed scanner to change the sub-scanning magnification error over time. 6. The scanner with a sub-scanning magnification correction function according to claim 3, wherein the scanner is also configured to correct the vertical scanning magnification.