JPH09200465A - Image reading device - Google Patents

Abstract

(57) [Abstract] [Problem] To control the motor slew up / down curve at the start and end of reading, when you want to perform motor slew up / down at the fastest speed, and at the intermittent operation when you want to read accurate images even slowly. Provided is an image reading device capable of preventing image deterioration by making them different. Kind Code: A1 An image reading apparatus for reading an original while moving an original scanning unit by a motor, a means for controlling start and stop of the motor while performing slewing up and down, and the read image. Intermittent reading operation that has a memory for storing data and stops the image reading by slewing down the motor when the above memory becomes full, and starts image reading by slewing up the motor after the memory full is released. In the above, the through-up / down curve is different from that at the start and end of reading.

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 reading an original while moving an original scanning unit by a motor, and particularly, at the start and end of reading when it is desired to slew up and down the motor at the fastest speed. ,
The present invention relates to an image reading apparatus capable of preventing image deterioration by differentiating the slew-up / down curves of the motor during intermittent operation in which an accurate image can be read slowly.

[0002]

2. Description of the Related Art Generally, image scanners, fax machines, and P
The PC is provided with an image reading device that moves the document scanning unit with a stepping motor to read the document in line units from the main scanning direction. Among them, the stepping motor starts and stops through and up. What is achieved by down is known.

[0003]

In the conventional image reading apparatus as described above, the throughput (the number of sheets read per minute) is usually desired to be increased as much as possible, so that the slew-up / down time of the stepping motor is as short as possible and the fastest. It is supposed to be done in. However, when the image memory becomes full, the image reading is stopped by the motor slewing down, and when the memory full is released and the image reading is started by the motor slewing up, the throughput is ignored. Therefore, it is necessary to obtain an accurate read image even if it is slow (usually, the definition of throughput is defined without intermittent reading). On the other hand, there is a problem in that an image obtained by the intermittent reading operation deteriorates when the motor slews up and down as compared to the case of constant-speed reading, due to the influence of vibration and the like due to the slewing up and down.
That is, in the case of performing the intermittent reading operation, the influence on the read image due to the overshoot of the motor is greatest at the time of slewing up / down. The present invention has been made to solve the above conventional problems.
The purpose is to change the image of the motor slew up / down by differentiating the curve at the start and end of reading, when you want the motor to slew up / down at the fastest speed, and at the intermittent operation when you want to read an accurate image even slowly. An object is to provide an image reading device that can prevent deterioration.

[0004]

In order to achieve the above object, the invention according to claim 1 is an image reading apparatus for reading an original while moving an original scanning unit by the motor, and starting and stopping the motor. Has a means for controlling while performing slew-up and slew-down, and a memory for storing the read image data. It is characterized in that in the intermittent reading operation in which image reading is started by slewing up the motor after the full state is released, the slew up / down curve is different from that at the start and end of reading. According to the image reading apparatus of claim 1, the slew-up / down curve is divided at the start and end of reading for which slew-up / down is desired to be performed at the highest speed, and for the intermittent operation at which slower accurate image reading is desired. As a result, it is possible to provide an image reading apparatus that does not reduce the throughput when the intermittent operation does not occur, and does not cause image deterioration when the intermittent operation occurs.

According to a second aspect of the present invention, in the image reading apparatus according to the first aspect, there are several kinds of slew-up / down curves dedicated to the intermittent reading operation, and the slew-up during the intermittent reading operation depends on the reading density and the like.・
The feature is that the down curve is selected from several types. According to the image reading device of claim 2,
By optimizing the slew-up / down curve at the time of intermittent operation depending on the reading density, it is possible to provide an image reading apparatus with less image deterioration.

According to a third aspect of the present invention, in the image reading apparatus according to the first aspect, the user selects a slew up / down curve during the intermittent reading operation. According to the image reading apparatus of the third aspect, when the user wants to perform the reading operation in a short time, the user wants to obtain the image with the least image deterioration by using the through-up / down curve at the start and end of the reading. In this case, it is possible to provide an image reading apparatus suitable for the purpose of use of the user by using a through-up / down curve dedicated to intermittent reading.

According to a fourth aspect of the present invention, in the image reading apparatus according to the first aspect, the user selects a slew-up / down curve for intermittent reading operation from several types of curves. According to the image reading apparatus of the fourth aspect, it is possible to obtain a better image by selecting the through-up / down curve for intermittent reading from among several types, which makes it possible for the user to use the image. It is possible to provide the existing image reading device.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram of an image reading apparatus embodying the present invention. In FIG. 1, the image reading apparatus is divided into a case where a document is placed on the platen glass 1 for reading and a case where a document stacked on a document tray 3 is fed and read. First, a document placed on the platen glass 1 is illuminated by an illumination lamp 7'integrated with a first mirror 5 ', and reflected light thereof is reflected by the first mirror 5'and a second unit integrally formed. Mirror 9 ',
It is scanned by the third mirror 11 '. After that, the reflected light is converged by the lens 13 and irradiated on the CCD 15 to be photoelectrically converted. The first mirror 5 ', the illumination lamp 7', the second mirror 9'and the third mirror 11 'are the traveling body motor 1
It is possible to move in the direction A using 7 as a drive source. Next, the originals stacked on the original tray 3 are picked up by the pickup roller 19, the pair of registration rollers 21, and the conveying drum 2.
3. The sheet is conveyed to the pair of discharge rollers 27 and 29 through the reading position B by the transport roller 25, and is discharged onto the discharge tray 31. Then, when the document passes through the reading position B, the illumination lamp 7 is moved to the vicinity of the reading position B.
The reflected light is scanned by the first mirror 5, the second mirror 9 and the third mirror 11 which are integrally formed. After that, the reflected light is condensed by the lens 13,
The CCD 15 is irradiated and photoelectrically converted. The pickup roller 19 and the registration roller pair 21 are driven by a paper feed motor (not shown), and the transport drum 23, the transport roller 25, and the paper discharge roller pairs 27, 29 are driven by a transport motor 33.

FIG. 2 is a block diagram of the internal configuration of the image reading apparatus shown in FIG. In FIG. 2, the scanner driving unit (SDU) 35 is a traveling body motor 17
And has an inverter to turn on the illumination lamp 7. Then, the sensor board unit (SB
U) The reflected light of the original incident on the CCD 15 on the C 37 is C
It is converted into an analog signal having a voltage value according to the intensity of light in the CD 15, and the analog signal is divided into odd bits and even bits and output. A dark potential portion of the analog image signal is removed by an analog data handling peripheral device (AHP) 41 on the motherboard unit (MBU) 39, odd bits and even bits are combined, and the gain is adjusted to a predetermined amplitude. It is input to the D converter and converted into a digital signal.

The digitized image signal is binarized after being subjected to shading correction, gamma correction, MTF correction, etc. by the scanner imaging peripheral device (SIP3) 45 on the scanner control unit (SCU) 43. , A page sync signal, a line sync signal, and an image clock, and is output as a video signal. And SI
The video signal output from P345 is output to the connector 47.
Is output to the image enhance unit (IEU) 49 via. The video signal output to the IEU 49 is subjected to predetermined image processing in the IEU 49, and then SC again.
Input to U43. The video signal input to the SCU 43 again is input to the selector 51. The other input of the selector 51 is the video signal output from the SIP345, and the IEU 49 can select whether to perform image processing. The output of the selector 51 is input to the selector 53. The other input of the selector 53 is a video signal from the (RCU) 55, and the reading surface of the original is selected. The RCU 55 is a unit that controls the back side reading of the original when reading both sides of the original at the same time.
The RCU 55 is controlled by the CPU 57 in the SCU 43 by serial communication, and transfers the read back side image data to the SCU 43 via the MBU 39 as a video signal. The video signal output from the selector 53 is connected to the selector 59 and the connector 61, and the other input of the selector 59 is the video signal from the video adapter 63. With the above configuration, the video adapter 63 can be connected to the end of the connector 61. Also, the selector 59
The video signal output of the above is input to the scan buffer controller (SBC) 65.

The video signal output from the SIP 345 through the above path is the SBC for managing the DRAM 64.
The data is input to 65 and stored in an image memory including a DRAM 64 including a single in-line memory module (SIMM) 67. The image data stored in the image memory is connected to the selector 69 and the connector 71. A data compression unit (DCU) 73 is connected to the connector 71.
3 compresses the input image data, the image data compressed by the DCU 73 becomes the other input of the selector 69, and it is possible to select whether the image data is compressed or not. The image data output of the selector 69 is sent to the host computer via the SCSI controller 75. CPU5 on the SCU43
7, ROM77, RAM79 are installed, SCS
It controls the I controller 75 to communicate with the host computer. The CPU 57 also includes a traveling body motor 17, which is a stepping motor, a paper feeding motor, and a conveyance motor 33.
The timing control is also performed. The ADU81 is
It has a function of relaying the power supply of the electrical components used in the automatic document feeder (ADF) unit.

Next, the traveling body motor 1 which is an essential part of the present invention.
The configuration operation for changing the slew-up / down curve at the time of slew-up / down of No. 7 during the intermittent reading operation will be described below. Here, the intermittent reading operation means an operation of stopping the image reading by slewing down the motor when the image memory is full, and starting the image reading by slewing up the motor after the memory full is released. FIG. 3 is a control block diagram of a main part for changing the slew-up / down curve. In FIG. 3, the main control unit is a CPU 57.
ROM 77, DRAM (image memory) 64,
The EEPROM 83, the image reading control unit 85, the conveyance motor control unit 87, the traveling body motor control unit 89, the conveyance sensor 91, and the operation unit 93 are connected to each other. A host computer 95 is connected to the CPU 57. In addition, the ROM 7
In FIG. 7, a plurality of through-up / down curves described later are stored.

FIG. 4 is a flow chart of the image reading operation when the motor is slewing up and down.
FIG. 6 is a diagram showing a slew-up / down curve in the image reading operation shown in FIG. 4, and FIG. 6 is a diagram showing a relationship between a step pulse of a motor and a line period at the time of slew-up. Next, with reference to FIGS. 4 and 5, the image reading operation when the motor slews up and down will be described. First, in step 101 of FIG. 4A, the motor is driven to start the original scanning unit, and in step 103, when the original scanning unit reaches the reading start position, reading is started. Here, the starting of the motor in step 101 is performed by the slow-up curve C shown in FIG.
Next, in step 105, the DRAM (image memory) 64 is read from the start of reading to the end of reading.
When the reading is completed without requiring the intermittent operation (step 107), the document is scanned along the curve C in FIG. The unit is returned to the initial position (step 109).

Next, the intermittent check operation of step 105 will be described in detail with reference to FIG. That is, in step 111 of FIG. 4B, it is determined whether or not the memory full flag indicating that the memory (DRAM 64) is full is ON. If the memory full flag is ON, in step 113, the memory Is determined to be empty (empty). If the memory is empty in step 113, the memory full flag is turned off in step 115.
Then, in step 117, the motor is slewed up along the intermittent exclusive curve D in FIG. Also,
If the memory full flag is not ON in step 111, it is determined in step 119 whether or not the memory is full. If the memory is full, in step 121, the memory full flag is turned ON. Then, in step 123, the motor is slewed down along the intermittent exclusive curve D in FIG.

Next, a second embodiment of the image reading apparatus according to the present invention will be described. In the second embodiment, in intermittent operation, one curve is selected from two kinds of intermittent exclusive curves depending on the read density and the like to perform slew up / down of the motor. That is, as shown in FIG. 7 for the intermittent check in step 105 of FIG. 4A, in step 125, the memory (DR
AM64) indicates that the memory full flag is O
Whether it is N or not is determined, and the memory full flag is ON.
If so, in step 127, it is determined whether or not the memory is empty. If the memory is empty in step 127, the memory full flag is turned off in step 129, the intermittent exclusive curve is selected in step 131, and the intermittent exclusive curve D in FIG. 5 is selected in step 133. The motor is slewed up, and in step 135, the motor is slewed up along the intermittent curve E shown in FIG. If the memory full flag is not ON in step 125, it is determined in step 137 whether or not the memory is full. If the memory is full, step 139 is performed.
At, the memory full flag is turned on, and an intermittent curve is selected in step 141.
In step 143, the motor is slewed down along the intermittent curve D shown in FIG.
In FIG. 5, the motor is slewed down along the intermittent curve E shown in FIG. Other operations are similar to those of the above-described first embodiment. According to the second embodiment, it is possible to provide an image reading apparatus with less image deterioration by optimizing the through-up / down curve of the intermittent operation according to the reading density and the like.

Next, a third embodiment of the image reading apparatus according to the present invention will be described. In the third embodiment, the through-up / down curve at the time of intermittent operation is selected by the user's selection. That is, FIG.
As shown in (a), in step 147, a curve for through-up / down in the intermittent operation by the user is selected, in step 149, the motor is driven to start the original scanning unit, and in step 151, the above-mentioned When the document scanning unit reaches the reading start position, reading is started. Here, in step 14 above.
The starting of the motor in 9 is performed by the slow-up curve C shown in FIG. Next, in step 153, the above DR is performed between the start of reading and the end of reading.
When the AM (image memory) 64 is in a full state and an intermittent operation is required to perform an intermittent check, and the reading is completed without the intermittent operation (step 1).
55), the document scanning unit is returned to the initial position along the curve C in FIG. 5 (step 157). Next, FIG.
The curve user selecting operation during the intermittent operation in step 147 will be described with reference to FIG.
5, the user selects the intermittent operation curve. In step 161, the curve C in FIG. 5 is selected, and in step 163, the intermittent dedicated curve D in FIG. 5 is selected.

Next, referring to FIG. 9, the above step 153
The intermittent check operation will be described. That is, FIG.
In step 165 of the above, the memory (DRAM6
In step 4167, it is determined whether the memory full flag indicating that the memory is full is ON. If the memory full flag is ON, it is determined in step 167 whether the memory is empty. If the memory is empty in step 167, the memory full flag is turned off in step 169, and in step 171, the motor is slewed up along the user selection curve selected in step 147. If the memory full flag is not ON in step 165, it is determined in step 173 whether the memory is full (full). If the memory is full, in step 175, the memory full flag is set. It is turned ON, and in step 177, the motor is slewed down along the user selection curve selected in step 147. The third above
According to the embodiment, when the user wants to perform the reading operation in a short time, the through-up / down curve C at the time of starting and ending the reading is used, and when the user wants to obtain an image with little image deterioration, the through-reading-only through is used. By using the up / down curve D, it is possible to provide an image reading apparatus that is suitable for the user's purpose of use. Other operations are similar to those of the above-described first embodiment. In addition, in FIG.
The curve user selection operation during the intermittent operation of step 147 of (a) is not limited to that of FIG.
As shown in (c), the curves C, D, and E may be selected.

[0018]

According to the present invention, the slew-up / down curve is divided by the start and end of reading for which the slew up / down is desired to be performed at the fastest speed and the intermittent operation for the purpose of slowly and accurately reading an image. It is possible to provide an image reading apparatus that does not reduce the throughput when the operation does not occur and does not cause image deterioration when the intermittent operation occurs. In addition, as the reading speed changes depending on the image reading density and the like, the vibration component that affects the image during intermittent reading also changes. In addition, the influence of the above components on the image due to the type of slew up / down curves also varies. Therefore, it is possible to provide an image reading apparatus with less image deterioration by optimizing the through-up / down curve at the time of intermittent operation according to the reading density. If the user wants to perform the reading operation in a short time, use the slew up / down curve at the start and end of reading, and if you want to obtain an image with minimal image deterioration, use the slew up / down curve for intermittent reading only. By using it, it becomes possible to provide an image reading apparatus that suits the purpose of use of the user. Further, by making it possible to select from among several types of through-up / down curves for intermittent reading, it is possible to obtain a better image, and it is possible to provide an image reading apparatus that is suitable for the user's purpose. Become.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an image reading apparatus embodying the present invention.

FIG. 2 is a block diagram of the internal configuration of the image reading apparatus shown in FIG.

FIG. 3 is a main-part control block diagram for changing a slew-up / down curve.

FIG. 4A is a flowchart of an image reading operation when the motor is slewing up / down, and FIG. 4B is an operation flowchart of step 105 of FIG. 4A.

5 is a diagram showing a through-up / down curve in the image reading operation shown in FIG.

FIG. 6 is a diagram showing a relationship between a step pulse of a motor and a line cycle during slew-up.

FIG. 7 is an operation flowchart of main parts of the second embodiment of the image reading apparatus according to the present invention.

FIG. 8A is a third image reading apparatus according to the present invention.
It is an operation | movement flowchart of embodiment, (b) is an operation | movement flowchart of step 147 of said (a).

9 is an operation flowchart of step 153 in FIG. 8 (a).

FIG. 10 is a main part operation flowchart of a fourth embodiment of an image reading apparatus according to the present invention.

[Explanation of symbols]

1 ... Original platen glass, 3 ... Original tray, 5 ... First mirror, 7 ...
Lighting lamp, 9 ... Second mirror,
11 ... Third mirror, 13 ... Lens,
15 ... CCD, 17 ... traveling body motor,
19 ... Pickup roller, 21 ... Registration roller pair, 23 ... Conveying drum,
25 ... conveying rollers, 27, 29
... Paper ejection roller pair, 31 ... Paper ejection tray,
33 ... Transport motor, 35 ... Scanner driving unit (SDU), 37 ... Sensor board unit (SBU), 39 ... Motherboard unit (MBU),
41 ... Analog data handling peripherals (AH
P), 43 ... Scanner control unit (SC
U), 45 ... Scanner imaging peripheral equipment (SIP
3), 47, 61, 71 ... Connector, 49 ... Image enhance unit (IEU), 51, 53, 59, 69
... selector, 55 ... RCU, 57 ... CPU,
63 ... video adapter, 64 ...
DRAM, 65 ... Scan buffer controller (SB
C), 67 ... Single in-line memory module (S
IMM), 73 ... Data compression unit (D
CU), 75 ... SCSI controller, 7
7 ... ROM, 79 ... RAM,
81 ... ADU, 83 ... EEPROM,
85 ... Image reading control section, 87 ... Conveyor motor control section, 89 ... Traveling body motor control section, 9
DESCRIPTION OF SYMBOLS 1 ... Conveyance sensor, 93 ... Operation part, 95 ... Host computer, 101
~ 177 ... each step,

Claims (4)

[Claims] 1. An image reading apparatus for reading a document while moving a document scanning unit by a motor, and means for controlling start and stop of the motor while performing slewing up and down, and reading the document. When the memory is full and the memory is full, the image reading is stopped by slewing down the motor, and after the memory full is released, the image reading is started by slewing up the motor. An image reading apparatus characterized in that the slew-up / down curve in reading operation is different from that at the start and end of reading. 2. The method according to claim 1, wherein there are several kinds of through-up / down curves for exclusive use in the intermittent reading operation, and the through-up / down curves for the intermittent reading operation are selected from several kinds according to the reading density and the like. The image reading device described. 3. The image reading apparatus according to claim 1, wherein the user selects a through-up / down curve during the intermittent reading operation. 4. The image reading apparatus according to claim 1, wherein the user selects a through-up / down curve for intermittent reading operation from among several types of curves.