JP2000349987A - Image reader, control method therefor and recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve resolution without changing optical path length by installing an image sensor freely inclinably and making the direction of a scanning line variable. SOLUTION: A scanning line 1 is set perpendicular to the vertical scanning direction, and horizontal scanning is performed with a reading width 1. Also, in scanning lines 2 and 3, and the scanning lines are inclined by appropriately varying an angle formed by the horizontal and vertical scanning lines. The line 2 is subjected to horizontal scanning with a reading width 2, while the angle of inclination is set to θ1 with respect to the line 1. The line 3 is further subjected to horizontal scanning with a reading width 3, while the angle of inclination is set to θ2 with respect to the line 1. A reading width is reduced in successively reading, by each pixel unit, by inclining a scanning line as the lines 2 and 3. For instance, for doubling the resolution with respect to resolution by the line 1, a scanning line is inclined so as to be 1/2 reading width with respect to the width 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image reading apparatus for realizing an increase in resolution by changing a reading width, a control method thereof, and a computer-readable recording medium for realizing the control.

[0002]

2. Description of the Related Art Image reading apparatuses can be roughly classified according to the application field.
document Imaging Management
nt) There are image reading devices used in the field. The image reading device is a flatbed type (fixed original type) and has an AD
Many have an F (automatic paper feeder) and are capable of manuscript sizes up to A3.

On the other hand, DTP (Desk) represented by a desktop simple electronic editing and printing system capable of creating a high print quality document
There are image reading devices used in the field of Top Publishing. DTP is an electronic editing system that can perform from document creation to editing and printing on a single desk, and has become feasible with the recent improvements in the performance of personal computers and the emergence of small laser printers. Image reading devices used in the DTP field often take in images such as photographs. As a reading medium, a print such as a film or a baked photograph is used, and the main types of the film are 4 inches x 5 inches, 8 inches x 10 inches, such as 35 mm, brownie, 60 mm x 60 mm, 60 mm x 45 mm. ing.

[0004] By the way, in the case of output with a high resolution in terms of the number of output lines and a large print such as a poster, a high resolution is required for the image reading apparatus. To realize high resolution, it is necessary to increase the number of bits of the CCD. However, at present, a CCD having about 10,000 pixels is realized in reading a color image, but the number of bits of the CCD tends to be limited.

Here, the following terms according to the present invention will be clarified by showing their definitions.

Scanning line: A virtual line that is sequentially read in pixel units in order to convert a two-dimensional image on a document into a one-dimensional electric signal. Main scanning: Scanning two-dimensional information on a document in the scanning line direction. That is, the scanning is performed by electronic scanning of the image sensor itself. Sub-scanning is performed by mechanical movement of a document, an image sensor, or a mirror. In the document transport type, the scanning is performed by scanning in the document transport direction.

FIG. 7 shows a diagram of the prior art. In the figure, a lens switching method will be described. A lens block 82 having a lens corresponding to the resolution is configured to be movable in the left-right direction so that each lens can be installed on the optical path. Further, it is configured to be vertically movable so that the distance between the image sensor and the lens can be changed. Further, the image sensor block 81 including the image sensor is configured to be vertically movable so that the distance between the image sensor and the lens can be changed. That is, in the lens switching method, the resolution is changed by changing the optical path length from the reading surface to the image sensor by selecting a lens corresponding to the resolution.

[0008]

As described above, the prior art has the following problems.

1) When changing the optical path length, it is necessary to drive the image sensor block and the lens block, which requires a large driving system, which leads to an increase in price and an increase in the size of the apparatus.

An object of the present invention is to realize a technique capable of increasing the resolution without changing the optical path length.

[0011]

In order to solve the above problems, the present invention takes the following measures.

In order to increase the resolution by changing the reading width, the image sensor is installed so as to be tiltable and the direction of the scanning line is changed.

By adopting the above means, the scanning width is inclined to reduce the reading width in pixel units, thereby realizing high resolution.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention adopts the following embodiments.

As shown in FIG. 1, the image reading apparatus is provided with an image sensor which is arranged so as to be tiltable by changing the direction of a scanning line.

By adopting the above-described embodiment, the reading width can be varied by appropriately changing the angle formed between the main scanning direction and the sub-scanning direction and inclining the scanning lines. Thereby, when reading is sequentially performed for each pixel, high resolution is realized by reducing the reading width.

Further, the image sensor is rotatably installed so that an angle formed between the main scanning direction and the sub-scanning direction is appropriately set. In addition, as shown in FIG. 2, the image sensor is rotatably installed around a center of the image sensor in the scanning line direction. Alternatively, as shown in FIG. 3, the image sensor is rotatably installed around a pixel constituting one end of the image sensor.

According to the above-described embodiment, the direction of the scanning line can be changed in accordance with the reading medium to be read by the image reading apparatus. Further, the direction of the scanning line is changed according to the resolution of the image reading device. If the image sensor is configured to be rotatable around the center in the scanning line direction, the deflection width of the mirror can be reduced.

In the control method of the image reading apparatus, the reading width is set by changing the direction of the scanning line according to the resolution, reading is started, and the reading boundary area at one end of the image sensor is detected. The storage of the read data is started when one end reaches the leading end of the original, and the read data is stored and aligned until the other end of the image sensor reaches the rear end of the original to generate image data.

By adopting the above-described embodiment, control of an image reading apparatus which realizes high resolution by inclining scanning lines is realized.

A recording medium for realizing control of the image reading apparatus includes a procedure for setting a reading width by changing a direction of a scanning line corresponding to a resolution, and a step of starting reading and setting one end of an image sensor. A procedure for detecting a read boundary area, a procedure for starting storage of read data from a point in time when one end of the image sensor reaches the leading end of the document, and a procedure for storing read data until the other end of the image sensor reaches a trailing end of the document. And a computer-readable program for executing the steps of performing alignment and generating image data. This program is stored in various appropriate recording media such as FDD and CD for recording the program.

According to the above-described embodiment, the present invention can be realized by using a program for operating a computer, and this program is an FD for recording the program.
Since it is stored in various suitable recording media such as D and CD, it is installed in an arbitrary processing device when necessary to perform processing.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A typical embodiment according to the present invention will be described with reference to FIGS. In the following, the same portions are denoted by the same reference numerals, and detailed description may be omitted.

FIG. 1 shows the principle of the present invention.

In FIG. 1A, the scanning line 1 is set in a direction perpendicular to the sub-scanning direction, and the main scanning is performed with a reading width of 1. In addition, the scanning lines 2 and 3 show a case where the angle formed between the main scanning direction and the sub-scanning direction is appropriately changed to incline the scanning lines. To set the tilt angle to θ1,
Main scanning is performed with a reading width of 2. Further, the scanning line 3 is set to have an inclination angle of θ2 with respect to the scanning line 1,
Main scanning is performed with a reading width of 3.

By inclining the scanning lines like the scanning line 2 and the scanning line 3, when reading is sequentially performed for each pixel, the reading width is reduced, so that high resolution is realized. For example, when the resolution is doubled with respect to the resolution of the scanning line 1, the scanning line is inclined so that the reading width becomes 1/2 of the reading width 1. That is, scan line 1
Is set to 60 degrees.

FIG. 3B shows a case where the optical path is folded by a mirror. When the image sensor 1 sequentially reads each pixel, the position where the pixel at the center of the sensor reads is the reading position a, the position where the pixel at one end of the sensor reads is the reading position b, and the position where the pixel at the other end of the sensor reads is the reading position. This is position c.

That is, in the main scanning, the sub-scanning position where the image sensor 1 sequentially reads each pixel differs depending on each pixel (bit). Therefore, it is necessary to correct the data to be read by storing the data in the sub-scanning direction.

Next, an example will be described in which the image sensor is rotatably installed so that the angle formed between the main scanning direction and the sub-scanning direction can be changed in order to tilt the scanning line.

FIG. 2 shows a diagram of an embodiment of the present invention.

In FIG. 1, a substrate 11 on which the image sensor 1 is mounted is mounted on a substrate frame 12.
The substrate frame 12 has a pulley 13 provided on a scanning line of the image sensor 1 and at a position corresponding to the center of the scanning line. The position of the substrate frame 12 is detected by a sensor 14 that detects one end corresponding to the scanning line of the image sensor 1.

That is, the state where the scanning line 1 shown in FIG. 1A is set in a direction perpendicular to the sub-scanning direction is detected. The pulley 13 is connected to a pulley 16 of a motor 17 by a timing belt 15. In this manner, by driving the motor 17, the scanning lines can be inclined like the scanning lines 2 and 3 shown in FIG. 1A.

FIG. 3 shows a diagram of an embodiment of the present invention.

In FIG. 1, a board 11 on which the image sensor 1 is mounted is mounted on a board frame 12.
The substrate frame 12 is provided with a gear 21 on a scanning line of the image sensor 1 and at a position corresponding to a pixel at one end of the scanning line. The position of the substrate frame 12 is detected by a sensor 14 that detects the other end corresponding to the scanning line of the image sensor 1. The gear 21 is connected to a gear 22 provided in a motor (not shown). As described above, by driving the motor, the scanning line 2 shown in FIG.
And the scanning line can be inclined like the scanning line 3.

Next, control of the image reading apparatus will be described.

FIG. 4 shows a diagram of an embodiment of the present invention.

Referring to FIG. 3, the image reading device 30 includes an optical unit 32, an arithmetic control unit 36, and a reading moving unit 3.
8 is a main configuration, and the reading medium 31 is mounted at a predetermined position to execute image reading. The optical unit 32 includes a light source lamp 33 for irradiating the reading medium 31 and a reading medium 31.
And a CCD tilt moving section 35 that rotates the CCD element 34 when necessary to tilt the scanning line. The reading moving unit 38 performs sub-scanning by moving the optical unit 32 or the reading medium 31.

The arithmetic control unit 36 controls the image reading device 30 in accordance with an instruction from the host device 41 connected to the image reading device 30, and transfers the read image data to the host device 41. The arithmetic control unit 36 includes an image data generating unit 37, and the image data generating unit 37 arranges the read data to generate regular image data.

The host device 41 comprises an arithmetic control unit 42, a driver program 43, a display unit 44, and an input unit 45. The arithmetic control unit 42 controls the host device 41. The driver program 43 exchanges data with the image reading device 30. The display unit 44 displays necessary data and operations in the image reading process. The input unit 45 inputs an instruction necessary for the image reading processing.

FIG. 5 is an explanatory view of an embodiment of the present invention.

Referring to FIG. 3A, an example in which the scanning line is inclined at an angle θ from a direction perpendicular to the sub-scanning direction will be described. When the image sensor 1 sequentially reads each pixel, the read data is stored from the time when the pixel at one end of the sensor reaches the leading end of the reading medium (point A). At this time, the position at which the other pixels including the other end of the sensor read out has not yet reached the leading end of the reading medium.

Therefore, when reading an image, in the main scanning, the sub-scanning position where the image sensor 1 sequentially reads each pixel is different depending on each pixel (bit).
The sub-scanning range is the distance d. That is, when reading an image, a range X indicated by a hatched portion is set as read data.

An example of detecting a point (point A) when the pixel at one end of the sensor reaches the leading end of the reading medium will be described with reference to FIG. The optical unit 32 (not shown) is moved from the home position located on the left side in FIG.
Reading is started in the sub-scanning direction, and after the pixel at one end of the sensor detects the boundary area B between the black portion and the white portion, the optical unit 32 is moved to the document abutting position, so that the pixel at one end of the sensor is positioned on the reading medium. You will reach the tip.

FIG. 6 shows a diagram of an embodiment of the present invention.

Referring to FIG. 5, a description will be given of a reading procedure in which the scanning line shown in FIG.
Note that the reference numerals refer to FIG.

In step S01, the CCD tilt moving section 35 confirms the reference position state in which the scanning line 1 shown in FIG. 1A is set in a direction perpendicular to the sub-scanning direction.

In step S02, the CCD tilt moving unit 35 tilts and drives the CCD element based on the resolution instruction in the image reading process transferred from the host device 41, and changes the tilt angle of the CCD element from the reference position to the angle θ.
(See FIG. 5A).

In step S03, the reading medium 31
Is mounted, and reading start is instructed.

In step S04, the optical unit 3
2 is driven, and reading is started by the reading moving unit 38 from the home position in the sub-scanning direction.

In step S05, it is determined whether the pixel at one end of the sensor (portion A in FIG. 5) is black in the main scanning direction.
If black, the process returns to step S05. If not black, the process proceeds to step S06.

In step S06, it is determined whether white is continuous in the prescribed number of scanning lines. If the white color is continuous, the process proceeds to step S07. If the white color is not continuous, the process returns to step S06.

In step S07, the optical unit 3
2 is moved by a predetermined amount in the sub-scanning direction and moved to the original abutment position, and then storage of read data is started.

In step S08, the image data generator 37 executes storage and alignment of the read data X (see FIG. 5A).

In step S09, the optical unit 3
It is determined whether or not the range for driving in the sub-scanning direction has moved to a distance d (see FIG. 5A). If it has moved, the process proceeds to step S10. If not, the process returns to step S08.

In step S10, the reading operation is completed, the optical unit 32 is stopped, and in step S11, the optical unit 32 is moved to the home position and stands by, and the process is terminated.

[0056]

As described above, according to the present invention, the following effects can be expected.

By providing an image sensor which can be tilted by changing the direction of the scanning line, the scanning line can be inclined by changing the angle formed between the main scanning direction and the sub-scanning direction appropriately. Can be varied. As a result, the reading width can be reduced when reading is sequentially performed for each pixel unit, and the resolution can be increased without changing the optical path length.

Further, the image sensor is rotatably installed so that an angle formed between the main scanning direction and the sub-scanning direction is appropriately set, so that the image sensor can correspond to a reading medium to be read by the image reading apparatus. Thus, the direction of the scanning line can be changed. Further, the scanning lines can be changed according to the resolution of the image reading device. In addition,
When the image sensor is configured to be rotatable around the center in the scanning line direction, the deflection width of the mirror can be reduced.

Further, the scanning width is set by changing the direction of the scanning line in accordance with the resolution, reading is started, the reading boundary area at one end of the image sensor is detected, and one end of the image sensor reaches the leading end of the document. The reading data storage is started from the time when the scanning is performed, and the reading data is stored and aligned until the other end of the image sensor reaches the rear end of the document to generate image data. A control of an image reading device that realizes high resolution without changing is realized.

Further, the present invention can be realized by using a program for operating a computer. This program is stored in various suitable recording media such as an FDD and a CD for recording the program. Can be installed in the processing device of (1) to perform processing.

[Brief description of the drawings]

FIG. 1 is a principle diagram of the present invention.

FIG. 2 is a diagram of an embodiment of the present invention.

FIG. 3 is a diagram of an embodiment of the present invention.

FIG. 4 is a block diagram of an embodiment of the present invention.

FIG. 5 is an explanatory diagram of an embodiment of the present invention.

FIG. 6 is a flowchart of an embodiment of the present invention.

FIG. 7 is a diagram of the prior art.

[Explanation of symbols]

 1: Image sensor 2: Lens 12: Substrate frame 13, 16: Pulley 14: Sensor 15: Timing belt 17: Motor 21, 22: Gear 30: Image reader 32: Optical unit 35: CCD tilt moving unit 36: Operation control Unit 37: image data generating unit 38: reading and moving unit

Claims (6)

[Claims] 1. An image reading apparatus, comprising: an image sensor which is arranged so as to be freely tilted by changing the direction of a scanning line. 2. An image reading apparatus according to claim 1, wherein said image sensor is rotatably installed so that an angle formed between a main scanning direction and a sub-scanning direction is appropriately set. 3. The image reading apparatus according to claim 2, wherein the image sensor is rotatably mounted around a center of the image sensor in a scanning line direction as a base point. 4. The image reading apparatus according to claim 2, wherein said image sensor is rotatably mounted around a pixel formed at one end of said image sensor as a base point. 5. A reading width is set by changing a direction of a scanning line in accordance with a resolution, reading is started, a reading boundary area at one end of an image sensor is detected, and one end of the image sensor reaches a leading end of a document. Storing the read data from the point of time when the image data is read, and storing and aligning the read data until the other end of the image sensor reaches the rear end of the document to generate image data. . 6. A computer, comprising: changing a direction of a scanning line according to a resolution to set a reading width; starting reading and detecting a reading boundary area at one end of an image sensor; The procedure for starting the storage of the read data from when the document reaches the leading edge of the document, and the procedure for storing and aligning the read data until the other end of the image sensor reaches the trailing edge of the document to generate image data. A recording medium that records a computer-readable program to be executed.