JPH0591260A - Picture reader - Google Patents

Abstract

PURPOSE:To attain the response in the unit of a scanning line in response to an external output request or an interruption request by moving a picture read means and an original picture relatively in the subscanning direction for one scanning line each synchronously with a clock signal. CONSTITUTION:A scanner printer 1, a controller 2 and a data processing unit 3 as an external device form a picture read system. The controller 2 generates a horizontal synchronizing signal synchronously with a clock signal of a prescribed frequency and a clock. A scanner 1a of the printer 1 scans an original picture in the main scanning direction for each scanning line synchronously with the clock and converts the picture into a read picture signal. Moreover, the scanner 1a moves the picture read means and the original picture relatively in the subscanning direction for each scanning line synchronously with the clock. The controller 2 outputs a horizontal synchronizing signal and a picture signal to the external device 3 and controls the output of the picture signal or the stop of the output in the unit of scanning lines in response to the stop request from the device 3.

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 image, converting it into an image signal and outputting the image signal.

[0002]

2. Description of the Related Art Recently, image information such as characters and images printed or printed on paper is read by a scanner, converted into a digital image signal and output to a printer to output a hard copy thereof. , Or an image reading device for outputting the converted digital image signal to an external data processing device such as an image filing system, a host computer, or a microcomputer to display it on a display connected to the data processing device. Has been done. As an image reading device of this type, when operating in conjunction with an image output device such as a printer or when operating as an input device of an image filing system, a horizontal synchronizing signal or a vertical synchronizing signal of a digital image signal is transmitted to an external device. There has been proposed an image reading apparatus (hereinafter referred to as a first conventional example) capable of switching between receiving from the device or occurring inside the device (for example, JP-A-60-21671). See the bulletin.).

In the image information reading apparatus of the first conventional example, a horizontal synchronizing signal having a constant frequency is internally generated, and the horizontal synchronizing signal is used when the digital image signal is transferred to the host computer of the system. It is used as a synchronization signal or as a horizontal synchronization signal when image information is scanned and read in the main scanning direction using an image sensor.

[0004]

However, in the image reading apparatus of the first conventional example, as described above, the horizontal synchronizing signal having a constant frequency is internally generated, and the horizontal synchronizing signal is digital. Since it is used as a synchronizing signal when transferring the image signal to the host computer of the system, or as a horizontal synchronizing signal when the image information is scanned and read in the main scanning direction using the image sensor, the image from the data processing device is used. There is a problem that it is not possible to respond to an output request or an image output interruption request in units of horizontal scanning lines of an image signal.

In the image reading apparatus of the first conventional example, since the horizontal synchronizing signal is generated at a constant frequency, the output speed of the image signal from the scanner is preset to a predetermined value. Therefore, in the image reading apparatus of the first conventional example, there is also a problem that the usable data processing apparatus is limited depending on the output speed of the image signal from the scanner.

Further, in the image reading apparatus of the first conventional example, high resolution conversion processing for increasing one horizontal scanning line of the image data read by the scanner to several scanning lines is performed, or When the resolution conversion processing such as the low resolution conversion processing for reducing several scanning lines to one scanning line is performed, the frequency of the horizontal synchronizing signal changes from a predetermined frequency according to the resolution conversion processing. The image signal cannot be sent to the external device. Therefore, the image reading apparatus of the first conventional example has a problem in that the resolution conversion process cannot be performed on the image data read by the scanner.

As described above, although it is not a device that performs resolution conversion processing on image data read by a scanner, it drives a pulse signal that drives a reference signal supplied to a line image sensor and an optical system for reading an original. By synchronizing the timing and controlling the pulse applied to the pulse motor, the scaling in the sub-scanning direction perpendicular to the main scanning direction, which is the element array direction of the line image sensor, or the image density conversion processing is performed. An image reading apparatus (hereinafter referred to as a second conventional example) is well known (see, for example, Japanese Patent Laid-Open No. 62-92670). This second
In the conventional image reading apparatus of, the pulse motor is
It is driven at low speed during reduction, and at high speed during enlargement.

However, the image reading apparatus of the second conventional example has the same problem as the first conventional example that the resolution conversion process cannot be performed, and achieves a high zoom ratio. In order to achieve this, high-speed control of the pulse motor is required, and it is necessary to design the pulse motor in consideration of the torque at its maximum speed and its margin, which results in relatively high performance and high cost. A pulse motor has to be adopted, and as a result, there has been a problem that the cost of the image reading apparatus including the pulse motor increases.

By the way, in a general conventional image reading apparatus, an image signal in a predetermined area in the sub-scanning direction is sent to a data processing apparatus such as a printer or a computer in synchronization with only a vertical synchronizing signal generated internally. The data processing device, which has been sent out, takes in only the image signal of a predetermined area in the sub-scanning direction necessary for the device, and processes the image signal. Therefore, in the conventional image reading device, the image size and the resolution corresponding to the predetermined external device are preset, and the vertical synchronizing signal is internally generated.

In recent years, various external devices for image processing having various capabilities have been developed and connected to image reading devices. However, since the conventional image reading apparatus has the above-described configuration, it can be connected only to a specific data processing apparatus having a corresponding predetermined capability. Therefore, for example, even if the specifications of the data processing device are known, if the specifications of the image signal interface do not match and it is not possible to connect to the image reading device that has already been purchased, or the specifications of the data processing device are unknown, It may not be possible to determine whether or not the image reading device can be connected.

In such a case, the period of the image signal processed by the data processing device in the sub-scanning direction (the output size in the vertical direction of the screen) is longer than that of the image signal input from the image reading device. Even if the period of the image signal output from the image reading device in the sub-scanning direction matches that of the image signal processed by the data processing device, a problem occurs if the resolution of the image signal to be processed by the data processing device is large. Occurs. That is, even though the image signal output from the image reading apparatus has ended, the data processing apparatus cannot receive the image signal, and thus the reception processing stops in the state of capturing the image signal. was there.

A first object of the present invention is to provide an image reading apparatus which can respond to an image output request or an interruption request from an external data processing device in units of scanning lines, has a simple structure and is inexpensive. Especially.

A second object of the present invention is to provide an image reading apparatus capable of changing the output speed of the image signal from the scanner according to the image data processing capability of various data processing apparatuses. is there.

Further, a third object of the present invention is to provide an image reading apparatus capable of outputting an image signal suitable for resolution conversion processing of an external data processing apparatus.

Still further, a fourth object of the present invention is to provide an image which can be received by the data processing device without trouble regardless of the length of the period in the sub-scanning direction of the image signal processed by the external data processing device. An object is to provide an image reading device that can output a signal.

[0016]

An image reading apparatus according to a first aspect of the present invention is a signal generating means for generating a clock signal having a predetermined frequency and a horizontal synchronizing signal synchronized with the clock signal. An image reading unit that scans and reads an original image for each scanning line in the main scanning direction in synchronization with the clock signal, and converts the image into an image signal; and the image reading unit and the original image in synchronization with the clock signal. And a signal output means for outputting the horizontal synchronizing signal and the image signal to an external device, and a stop request signal input from the external device. And a control unit for stopping the operations of the moving unit and the signal output unit in response to the stop request signal received by the receiving unit. And it features.

An image reading apparatus according to a second aspect of the present invention is the image reading apparatus according to the first aspect, further comprising a resolution signal indicating the resolution of the image signal to be output from the external device. It is characterized by including a receiving means, and the signal output means thins out the horizontal synchronizing signal at a rate corresponding to the resolution signal and outputs the thinned-out horizontal synchronizing signal.

Further, in the image reading apparatus according to claim 3 of the present invention, there is provided a signal generating means for generating a plurality of clock signals each having a different frequency, and an external device inputting the plurality of clock signals. Of the plurality of clock signals generated by the signal generating means in response to the selection signal received by the receiving means. A signal selecting means for selecting and outputting, and an image reading means for scanning and reading an original image for each scanning line in the main scanning direction in synchronism with the clock signal output from the signal selecting means and converting it into an image signal. , Another signal generating means for generating a horizontal synchronizing signal in synchronization with the clock signal output from the signal selecting means, the horizontal synchronizing signal and the image signal. Characterized by comprising a signal output means for outputting the part device.

An image reading apparatus according to a fourth aspect of the present invention further includes a signal generating means for generating a clock signal having a predetermined frequency and a horizontal synchronizing signal synchronized with the clock signal, and An image reading unit that scans and reads an original image for each scanning line in the main scanning direction in synchronization with a clock signal and converts it into an image signal; and the image reading unit and the original image that are synchronized with the clock signal Moving means for moving the scanning lines relatively at a predetermined moving speed in the sub-scanning direction, signal output means for outputting the horizontal synchronizing signal and the image signal to an external device, and input from the external device, A high resolution signal indicating that the image signal to be output has a predetermined high resolution or a low resolution signal indicating that the image signal to be output has a predetermined low resolution is received. Receiving means, first control means for controlling the moving speed of the moving means in response to the high resolution signal received by the receiving means so that the image signal has a predetermined high resolution; In response to the low resolution signal received by the receiving means, the image signal has a predetermined low resolution, and the horizontal sync signal is thinned out at a rate corresponding to the low resolution signal and output. A second control means for controlling the means.

According to a fifth aspect of the present invention, the image reading apparatus includes a first signal generating means for generating a clock signal having a predetermined frequency and a horizontal synchronizing signal synchronized with the clock signal. An image reading unit that scans and reads an original image for each scanning line in the main scanning direction in synchronization with the clock signal and converts the image into an image signal; and the image reading unit and the original image in synchronization with the clock signal. Moving means for moving one scanning line relative to each other in the sub-scanning direction at a predetermined moving speed, signal output means for outputting the horizontal synchronizing signal and the image signal to an external device, and synchronizing with the clock signal. Second signal generating means for generating an internal sub-scanning effective signal indicating an effective area of the image signal in the sub-scanning direction, and input from the external device, and processable by the external device. Receiving means for receiving an external sub-scanning valid signal indicating an effective area of the image signal in the sub-scanning direction, the internal sub-scanning valid signal is generated by the second signal generating means, and the external sub-scanning valid signal is When being received by the receiving means, first control means for controlling the signal output means so as to output the image signal, and the internal sub-scanning valid signal are generated by the second signal generating means. The second sub-scanning effective signal is controlled by the receiving means so that a predetermined image signal is output when the external sub-scanning valid signal is received by the receiving means.
And a control means of.

Further, the image reading apparatus according to the sixth aspect is
The image reading apparatus according to claim 5, wherein the predetermined image signal is an image signal indicating a white or black pixel.

[0022]

In the image reading apparatus according to the present invention, the signal generating means generates a clock signal having a predetermined frequency and a horizontal synchronizing signal in synchronization with the clock signal, and the image reading means The original image is scanned and read in the main scanning direction for each scanning line in synchronization with the clock signal and converted into an image signal. Further, the moving means moves the image reading means and the original image relative to each other in the sub-scanning direction by one scanning line in synchronization with the clock signal, and the signal output means moves the horizontal synchronizing signal and the horizontal synchronizing signal. The image signal is output to an external device. Next, the receiving means receives a stop request signal input from the external device, and the control means responds to the stop request signal received by the receiving means by the moving means and the signal output means. Stop the operation.

Therefore, for example, even when the processing speed of the external device for receiving the image signal is slow and the processing cannot follow the image signal due to the difference in the capabilities of the image reading device and the external device, the scanning line unit is used. Since the output or stop of the output of the image signal can be controlled, any external device can receive the image signal normally without any loss of the image signal. It will be possible.

In the image reading device according to the second aspect,
The another receiving means receives a resolution signal indicating the resolution of an image signal to be output, which is input from the external device, and the signal output means thins out the horizontal synchronizing signal at a rate corresponding to the resolution signal. Output. Therefore, the image reading apparatus outputs the image signal after converting the resolution of the image signal to be output to the resolution of the image of the image signal corresponding to the resolution signal. An image signal can be normally output to an external device without depending on the resolution.

In the image reading apparatus according to claim 3,
The signal generating means generates a plurality of clock signals each having a frequency different from each other, and the receiving means receives a selection signal input from an external device and indicating selecting one of the plurality of clock signals. To receive. Also,
The signal selecting means selects and outputs one of the plurality of clock signals generated by the signal generating means in response to the selection signal received by the receiving means, and the image reading means, In synchronization with the clock signal output from the signal selecting means, the original image is scanned for each scanning line in the main scanning direction, read, and converted into an image signal.
Further, the another signal generating means generates a horizontal synchronizing signal in synchronization with the clock signal output from the signal selecting means, and the signal outputting means outputs the horizontal synchronizing signal and the image signal to an external device. Output to.

Therefore, the image signal can be normally output to the external device without depending on the frequency of the clock signal of the image signal processed by the external device.

In the image reading apparatus according to the fourth aspect,
The signal generating means generates a clock signal having a predetermined frequency and a horizontal synchronizing signal synchronized with the clock signal, and the image reading means synchronizes the original image with each scanning line in synchronization with the clock signal. Then, it is scanned in the main scanning direction, read, and converted into an image signal. Further, the moving means moves the image reading means and the original image relative to each other one scanning line at a predetermined moving speed and in the sub-scanning direction in synchronization with the clock signal, and the signal outputting means, The horizontal synchronizing signal and the image signal are output to an external device. Further, the receiving means is a high-resolution signal indicating that the image signal to be output has a predetermined high resolution and is input from the external device, or a low signal indicating that the image signal to be output has a predetermined low resolution. Receiving a resolution signal, the first control means responds to the high resolution signal received by the receiving means to control the moving speed of the moving means so that the image signal has a predetermined high resolution. And the second control means is responsive to the low resolution signal received by the receiving means, wherein the image signal has a predetermined low resolution and the horizontal sync signal corresponds to the low resolution signal. The signal output means is controlled so that the signal is thinned out and output at the ratio.

Therefore, the image reading apparatus outputs the image signal after converting the resolution of the image signal to be output to the resolution of the image of the image signal corresponding to the resolution signal, so that the external apparatus processes it. The image signal can be normally output to the external device without depending on the resolution of the image signal.

In the image reading apparatus according to the fifth aspect,
The first signal generating means generates a clock signal having a predetermined frequency and a horizontal synchronizing signal in synchronization with the clock signal, and the image reading means synchronizes the original image with the clock signal. Each scanning line is scanned and read in the main scanning direction and converted into an image signal. Further, the moving means moves the image reading means and the original image relative to each other one scanning line at a predetermined moving speed and in the sub-scanning direction in synchronization with the clock signal, and the signal outputting means, The horizontal synchronizing signal and the image signal are output to an external device. Further, the second signal generating means generates an internal sub-scanning effective signal indicating an effective area of the image signal in the sub-scanning direction in synchronization with the clock signal, and the receiving means inputs from the external device. The external sub-scanning valid signal indicating the effective area in the sub-scanning direction of the image signal that can be processed by the external device is received. Next, the first control means outputs the image signal when the internal sub-scanning valid signal is generated by the second signal generating means and the external sub-scanning valid signal is received by the receiving means. The second control means controls the signal output means such that the internal sub-scanning valid signal is not generated by the second signal generating means and the external sub-scanning valid signal is received by the second control means. The signal output means is controlled so that a predetermined image signal is output when being received by the means.

Therefore, when the external device is receiving an image signal, even if there is no image signal to be output from the image reading device, a predetermined image is generated in response to the external sub-scanning valid signal. Since the signal is output to the above external device,
All image signals, no matter what the external device,
It is possible to receive the image signal normally without the loss of the image signal.

In the image reading apparatus according to the sixth aspect,
The image reading apparatus according to claim 5, wherein the predetermined image signal is an image signal that preferably represents a white pixel in the case of a positive image signal, and preferably a black pixel in the case of a negative image signal. It is an image signal.

[0032]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment according to the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows the basic arrangement of an image reading system according to an embodiment of the present invention. As shown in FIG. 1, the image reading system of the present embodiment includes a scanner printer 1, a controller 2, and a data processing device 3 provided as an external device. The scanner printer 1 is
A scanner unit 1a that reads image information such as characters or an original image printed or printed on a sheet of paper, converts the image information into digital image data, and outputs the digital image data, and a laser printer unit 1b. The data processing device 3 is, for example, a device such as a word processor, a personal computer, or another host computer, and is connected to the scanner printer 1 via the controller 2 having a video interface circuit.

The scanner printer 1 has the following three basic operation modes. (A) Scanner mode: An original image is read by the scanner unit 1a of the scanner printer 1 and converted into image data, and then transmitted to the data processing device 3 via the video interface circuit of the controller 2. Then, the data processing device, for example, CRs the image of the received image data.
It is displayed on the T display 3a. (B) Printer mode: The image of the image data received from the data processing device 3 via the video interface circuit of the controller 2 is printed out by the laser type laser printer unit 1b of the scanner printer 1. (C) Copy mode: After the original image read by the scanner unit 1a is read and converted into image data, the laser printer unit 1b of the scanner printer 1 directly outputs the image of the image data based on the converted image data. ,
Print out.

The operation mode of the scanner printer 1 can be switched by an operation mode setting key (not shown) on the operation panel 4 which will be described later.
Based on the command signal from the data processing device 3, the above 3
It can be set to one of two operating modes.
That is, the scanner printer 1 is used as (a) a scanner, (b) as a printer, or
(C) Used as a copier, it can be set to any one. Therefore, in consideration of usability for operating in the copy mode, the scanner printer 1 is provided with a simple operation panel 4 as shown in FIG.

In FIG. 2, an exposure level key 5 is a key for changing over the exposure level in three steps, and the character / character
The photo key 6 is a key for switching between a character reading mode when the original image to be read is only characters and a photo reading mode when the original image to be read includes a photo. In the case of, the simple binary processing is performed on the image data, and in the photo reading mode, the error dispersion processing is performed on the image data. The number-of-copies key 7 is a key for setting the number of copies, and includes an up key 7a and a down key 7b, and the set number of copies is displayed on the light emitting diode display portion 7c. Further, the start key 8 is a key for starting the copy operation, and the light emitting diode (hereinafter referred to as LED) 8a is turned on during the copy operation. LED 9a
9 to 9c display the density set by the exposure level key 5, and the LEDs 9d, 9e display the reading mode (character reading mode or photo reading mode) set by the character / photo key 6. Further, the operation panel 4 includes an operation mode setting key (not shown) for switching the above three operation modes.

The structure of the scanner section 1a of the scanner printer 1 is shown in FIG. As shown in FIG. 3, the scanner unit 1a
Is mounted and fixed on the laser printer unit 1b of the scanner printer 1. The scanner unit 1a includes a document tray 11 for feeding a document and a contact-type line that scans a document image in a main scanning direction which is a direction perpendicular to a document feeding direction to read and convert the document image into digital image data. Type CCD image sensor 12, a conveyance roller 13 for conveying the document to a predetermined position of the CCD image sensor 12, and a resist for positioning the reading position of the document in the sub-scanning direction which is a direction perpendicular to the main scanning direction. A roller 14, a discharge roller 15 for discharging the document after reading the document image, a document conveyance path 16, and a discharge roller 17 are provided.

On the other hand, as shown in FIG. 3, the laser printer section 1b has the following structure below the scanner section 1a. In FIG. 3, the charging charger 22 applies a uniform charge to the photosensitive drum 21 before the irradiation of the laser beam in order to form an electrostatic latent image of a document image by the laser beam. Next, the electrostatic latent image of the original image is formed on the photosensitive drum 21 by the irradiation of the laser beam, and the developing device 23 develops the electrostatic latent image formed by the laser beam to form the toner image on the photosensitive drum 21. Let it form. Further, the transfer charger 24 transfers the toner image developed by the developing device 23 onto the sheet, and then separates the separation belt 25.
Means that the above-mentioned paper on which the toner image is transferred is set to the photosensitive drum
Separate from. The toner remaining after the transfer is collected by the cleaner blade 26. Eraser 2
7 is provided in order to remove the residual charge and make the charging by the charging charger 22 uniform. Then, the density of the toner image transferred onto the paper is read by the density reader 28 and automatically controlled to the exposure level set by the exposure level key 5 in FIG.

The laser printer unit 1b also serves as a paper cassette 29 for accommodating sheets, a half-moon type sheet feeding roller 31 for guiding the sheet to the conveying path, a conveying roller 32, and a sheet feeding roller for manually feeding the sheet. The transport roller 33 and the registration roller for positioning the recording position in the sub-scanning direction with respect to the sheet (hereinafter, the direction in which the laser beam scans the sheet is referred to as the main scanning direction, and the direction perpendicular thereto is the sub-scanning direction). 34, a fixing roller 35 for fixing the toner image transferred by the transfer charger 24 onto the paper, a main body discharge roller 36, a reversing unit 37 for discharging the paper so that the back surface of the paper is the top surface, and a discharge And a roller 38. The laser printer unit 1b further includes a magnet group 39 for identifying the paper size in the paper cassette 29, and the sensor 41 detects whether or not there is a magnet in the 3-bit storage frame to identify the paper size. .. The presence of the paper in the paper cassette 29 is detected by the paper empty sensor 42. Note that PS1 and PS2 are paper sensors for detecting the presence of paper, respectively.

The optical system of the laser printer section 1b is shown in FIG. In FIG. 4, reference numeral 45 denotes a laser diode (hereinafter, L
Called D. ), And is modulated and driven by an LD drive unit 66 (see FIG. 5) described later. Reference numerals 46 and 47 are so-called collimator lenses and cylindrical lenses for correcting the spread of the laser beam 50, respectively. Reference numeral 48 denotes a polygon mirror, which rotates to generate a laser beam 50.
Is configured to scan the photoconductor drum 21 to obtain scan light 49. Reference numeral 51 is an fθ lens for scanning the photosensitive drum 21 with a laser beam at a uniform speed, 52 and 53 are folding mirrors for guiding the laser beam to the photosensitive drum 21, and 54 is a printing position in the main scanning direction. The scanning light 49 is configured to scan the photosensitive drum 21 after passing through the beam detector 54.

As shown in FIG. 5, the scanner printer 1 includes an image sensor 12, an image processing section 62, a control section 63, a scanner mechanism section 64, and a printer mechanism section 65.
Laser drive unit 66, interface unit (I / F
Section) 67 and a horizontal synchronizing signal switching section 68. Each block has the following functions.

The image sensor 12 reads the information of the document image written or printed on the document sheet and converts it into digital image data, and the image processing section 62 converts the digital image data output by the image sensor 12. The image data is output to an output device such as the laser printer unit 1b of FIG. 1 and the display 3a of the data processing device 3. The control unit 63 includes the image processing unit 62 and the scanner mechanism unit 6.
4, controlling each operation of the printer mechanism unit 65, the laser drive unit 66, the interface unit 67, and the like. The scanner mechanism unit 64 drives the scanner unit 1a in FIG. 1, and the printer mechanism unit 65 drives the printer unit 1b.
The laser drive unit 66 modulates and drives the laser diode based on the input digital image data. The interface section 67 performs signal conversion of command signals and image data from the controller 2. The horizontal synchronization signal switching unit 68 selectively selects a plurality of horizontal synchronization signals for image data to be output to the controller 2 based on a command signal from the controller 2 input to the control unit 63 via the interface unit 67. Switch.

The structure of the control unit 63 is shown in FIG. As shown in FIG. 6, the control unit 63 includes a CPU 71 and a ROM 7
2 and a RAM 73. The CPU 71 is a processor for sequentially controlling the entire scanner printer 1, and the ROM 72 stores a control program to be executed by the CPU 71, data for executing the control program, and the like. Also, the RAM 73
Is used as a work area for temporarily storing the data required when the CPU 71 executes the control program. The CPU 71 has an LED drive signal for lighting an LED (not shown) for irradiating an original mounted on the scanner mechanism section 64, and a motor for driving a stepping motor (pulse motor) M64 for conveying the original. The drive signal is output to the scanner mechanism unit 64. On the other hand, the scanner mechanism unit 64 outputs to the CPU 71 a sensor output signal output from a plurality of sensors (not shown) provided to detect the document transport position.

The CPU 71 includes an external data processing device 3
A scan request signal that becomes active when a scan request is issued from the scanner mechanism unit 64 is input from the scanner mechanism unit 64 when it is desired to stop the operation of the scanner mechanism unit 64 during scanning. An image output stop request signal for stopping the motor for the CPU is sent from the external data processing device 3 to the CPU via the controller 2.
71 is input. Further, the data processing device 3 outputs the following command signal to the CPU 71. This command signal contains the resolution of the image data to be output (setting dp
The information specifying i), the frequency of each synchronization signal of the data processing device 3, the information indicating the data processing speed, and the like are included. On the other hand, the CPU 71, which will be described later in detail, sends image data to the external data processing device 3,
Image clock, horizontal sync signal HSYNC- (hereinafter, HS
It is called a YNC signal. ) And a main scanning valid signal HD- (hereinafter referred to as HD signal) and the like, and outputs an external device output control signal for controlling the output of each signal to the interface gate circuit 77 of the image processing unit 62. The CPU 71 also supplies a control signal for inputting and outputting necessary data to the image processing unit 62. In addition, in the specification and drawings of the present application, a signal having "-" after the symbol of the signal is a low active signal.

As shown in FIG. 6, the image processor 62 includes a clock generator 74, a resolution converter 75, and a binarizer 7.
6, an input / output unit (I / O unit) 78, and an interface gate circuit 77. The basic functions of these blocks will be described below.

The clock generating section 74 generates and outputs a pixel clock required for each processing section of the image processing section 62 and the image sensor 12. Also, the resolution conversion unit 75
Performs edge enhancement processing of 3 × 3 on the input image data, creates line data required for edge processing and resolution conversion, and sets the resolution of the output image data to the resolution from an external device. The image data having a predetermined resolution is converted according to the designated command signal, and the image data having the converted resolution is output. Further, the binarization unit 76
The multi-valued image data is binarized to output binary image data, and the input / output unit 78 sets the input / output of each processing unit of the image processing unit 62 while the interface unit gate circuit 7 is set.
Reference numeral 7 performs a predetermined signal conversion on the input image data to be processed and each signal so as to have a format suitable for an external data processing device, and outputs the data to the data processing device.

The structure of the clock generator 74 is shown in FIG.
As shown in FIG. 7, the clock generating section 74 includes a signal generator 81, a counter 82, a selector 83, an SH generating section 84, and an HD generating section 85. The signal oscillator 81 generates a clock signal having a predetermined frequency and outputs it to the counter 82. The counter 82 counts the input clock signal, generates a first clock signal having a first frequency for each predetermined first count value, and outputs the first clock signal to the first input terminal of the selector 83. While outputting as the clock 1 to the resolution conversion unit 75, a second frequency having a second frequency lower than the first frequency is output for each predetermined second count value.
And outputs it to the second input terminal of the selector 83. The CPU 71 is an external data processing device 3
From the first clock signal and the second clock signal based on the device capability of the device 3 such as the resolution included in the command signal from And outputs the clock select signal including the signal to the control signal terminal of the selector 83. Selector 8
3 selects one of the first clock signal and the second clock signal based on the input clock select signal and outputs it as clock 2.

Further, the SH generator 84 has two counters, and the shift signal SH- (hereinafter referred to as SH signal) required by the CCD image sensor 12 is C respectively.
Low-level period T of the SH signal input from the PU 71
After the data indicating shl and the data indicating the period Psh of the SH signal are set as the respective counter values in the respective counters in the SH generating section 84, the clock 1 is counted to generate the data as shown in FIG. And output.

The HD generation section 85 has two counters and indicates the effective width of the document in the horizontal direction (main scanning direction).
Generate a signal. Similar to the SH generation unit 84, the HD generation unit 85 also sets data indicating the period Ttr from the rising edge of the SH signal to the falling edge of the HD signal and the period Tle from the rising edge of the SH signal to the rising edge of the HD signal. After the data shown is set in each counter in the HD generation unit 85 as each counter value, the clock 2
, The HD signal is generated and output as shown in FIG. The counter included in the HD generation unit 85 is cleared by the low level of the SH signal when the HD signal is at the high level, and is not cleared during the output period of the HD signal.

Next, the resolution converter 75 will be described. The resolution converter 75, as shown in FIG.
A 3-line buffer memory including IFO memories 91 to 93 is provided. The FIFO memories 91 to 93 have the following features as compared with a normal static RAM.

(1) No input of an address is required in the write cycle and the read cycle, and the memory is accessed at each rising edge of the write clock WCK and the read clock RCK. (2) The write operation and the read operation are completely asynchronous, and data input / output DIN (0-7) and DOUT (0-
Since 7) is a dual port, it is possible to perform write cycle and read cycle operations independently. (3) Since the address cannot be specified, input / output can always perform only the first-in first-out operation. (4) The internal address pointer has a write reset terminal (bar WRES) and a read reset terminal (bar RRE).
The write address and the read address can be reset to zero by activating S).

Next, the block diagrams of FIGS. 9 and 10 and FIG.
Using the operation timing chart of No. 1, the resolution conversion unit 7
The operation of No. 5 will be described.

First, the three FIFO memories 91,
The 3-line buffer memory including 92 and 93 converts the input image data into each line data of three horizontal scanning lines. Then, the converted three line data are transferred to the FIFO by the latches 101, 102 and 103 in FIG.
The read clock RCK of the O memories 91 to 93 is set to 1/4.
The divided clock (1/4 RCK) is latched, and the image data of one identical pixel is divided into four in the time axis direction and output. Next, a weighting coefficient having the effect of the smoothing process and the edge enhancement process is recorded for each image data of the three line data divided into four.
The weighting coefficient data read from M104 is multiplied by the multiplication circuits 111 to 119, and the data of the multiplication results are all added by the addition circuit 105 to obtain weighted addition data. Finally, based on the clock MAGCK generated by the clock generator 74 according to the output resolution, the weighted addition data calculated as above is latched by the latch 106, whereby image data having a resolution corresponding to the output resolution is obtained. obtain.

The structure of the binarization unit 76 is shown in FIG. The binarization unit 76 binarizes all input image data.
An entire surface binarization unit 96 that performs binarization processing, an entire surface middle top portion 97 that performs predetermined pseudo halftone binarization processing on all input image data, and an error with respect to input image data. An error distribution binarization unit 98 that performs binarization processing by the dispersion method, and output from each binarization unit 96, 97, 98 based on a selection signal input from the input / output unit (I / O unit) 78. A selector 99 which selects and outputs one of the binarized image data.

The structure of the interface gate circuit 77 is shown in FIG. The interface gate circuit 77 has four
Two NAND gates G2, G3, G4 and G5 are provided. The control signal output from the CPU 71 of FIG. 6 is input to the first input terminal of the NAND gate G2, the second input terminal of the NAND gate G3, the second input terminal of the NAND gate G4, and the first input terminal of the NAND gate G5. .. Also, CPU
The valid signal output from the output terminal 71 and described later in detail is input to the second input terminal of the NAND gate G2, and the image data is input to the third inverting input terminal of the NAND gate G2. Further, the clock 2 generated by the clock generator 74
Is input to the first inverting input terminal of the NAND gate G3. Furthermore, the S generated by the SH generation unit 84
The H signal is input to the first inverting input terminal of the NAND gate G4, and the HD signal generated by the HD generator 85 is input to the third input terminal of the NAND gate G4 and the NAND gate G5.
Is input to the second inverting input terminal of the. At this time, the NAND gates G2, G3, G4 and G5 respectively output the image data, the image clock, the HSYNC signal and the main scanning enable signal HDD- (hereinafter referred to as the HDD signal). Here, the HDD signal is a signal indicating the valid period of the image data in one scanning line in the image data output from the scanner printer 1.

Next, each of the signals such as the image data, the image clock, the HD signal, the HSYNC signal and the like appearing in the above description will be described more specifically.

<Clock 1, Clock 2> Clock 2
Is one clock signal selected from a first clock signal having the same frequency as clock 1 and a second clock signal having a frequency lower than clock 1. The reason why the frequency of the clock is made selectable in this way is because it is considered that the image data cannot be read by the data processing device 3 according to the clock 1.

<HD signal> The HD signal is the horizontal direction of the original,
That is, it is a signal indicating the effective area in the main scanning direction, and CP
The generation period of the HD signal generated by each data of the periods Ttr and Tle set by U71 is changed depending on the output size of the image data in the main scanning direction (output period in the main scanning direction), output resolution, and the like. It

<CPU horizontal sync signal CPUHSYNC- input to CPU 71> CPU horizontal sync signal C generated by NAND gate G1 and input to CPU 71
PUHSYNC- (hereinafter, referred to as CPUHSYNC signal) will be described below. As shown in FIG. 6, the SH signal generated by the clock generator 74 is input to the first inverting input terminal of the NAND gate G1, and the HD signal generated by the clock generator 74 is the second input terminal of the NAND gate G1. Entered in the CP
The UHSYNC signal is input to the CPU 71 from the NAND gate G1.

FIG. 14A shows clock 1 when the frequency of clock 1 matches the frequency of clock 2.
14B is a timing chart showing the relationship between the clock 2, the SH signal, the HD signal, and the HSYNC signal, and FIG.
Is the clock 1, clock 2, SH signal when the frequency of clock 1 does not match the frequency of clock 2,
6 is a timing chart showing the relationship between the HD signal and the HSYNC signal.

When the external data processing device 3 is operable with the image clock having the same frequency as the frequency of the clock 1, as shown in FIG. 14A, the SH signal is directly used as the HSYNC signal. Is output to.
On the other hand, when the external data processing device 3 cannot operate with the image clock having the same frequency as the frequency of the clock 1, the SH signal is thinned out by the NAND gate G4 of FIG. 13 as shown in FIG. It is output to the data processing device 3 as an HSYNC signal. That is, FIG. 14B
As indicated by the dotted line pulse, the low level SH signal is not output when the HD signal is low level.

The CPU 71, as will be described later in detail,
The stepping motor M64 is driven in synchronization with the CPUHSYNC signal. Therefore, when the clock 2 having a frequency different from the frequency of the clock 1 is selected, the driving speed of the stepping motor M64 can be slowed down, and the external data processing device 3 which is slow in the receiving process when receiving the image data can be dealt with.

<Image data, image clock, HSYNC
Signal, HDD signal> When a high-level control signal generated by being controlled by the main routine of the control unit 63 described later is input to the NAND gates G2 to G5, as shown in FIG. The output of image data, image clock, HSYNC signal, and HDD signal output to the external data processing device 3 is prohibited. The valid signal input to the NAND gate G2 indicates whether the image data is directly output from the image sensor 12 to the external data processing device 3 or fixed to the image data of the "white" pixel. Used to control.

<H output to the external data processing device 3
SYNC signal> This HSYNC signal is generated by the NAND gate G4 based on the SH signal and the HD signal generated by the clock generator 74 and the control signal output from the CPU 71, as shown in FIG. It is a horizontal synchronization signal. As described above, in the case of FIG. 14B, the HSYNC signal is thinned out and output.

Next, each of the three operation modes of the scanner printer 1 having the above-described configuration, that is, the scanner mode, the printer mode, and the copy mode will be described.

<Scanner Mode> FIG. 15 shows the main routine of the scanner mode executed by the CPU 71 in the control unit 63 of the scanner printer 1 of this embodiment. In step S1, initial setting is performed based on information necessary for the scanner operation such as output size, output resolution, external device capability, exposure level, etc. included in the command signal sent from the external data processing device 3. Then, in this initial setting, a status answer “normal reception” is sent to those that can be accepted, and a status answer “abnormal” is sent to those that cannot be accepted to the data processing device 3.

When the initial setting is completed, the presence or absence of the next command signal from the data processing device 3 is determined in step S2, and when there is a command signal (step S2).
(YES in step S3), the command signal is analyzed in step S3, information necessary for the scanner operation is fetched based on the analysis result, and the necessary processing is executed. It is determined based on the scan request signal whether or not a scan request is made. If it is determined that there is no command signal in step S2 (NO in step S2), the process proceeds to step S4 without executing step S3, and it is determined whether or not a scan request is made.

If it is determined in step S4 that the scan is requested (YES in step S4), the scan process is executed in step S5, and then the process returns to step S2. When it is determined in step S4 that the scan process is not required (NO in step S4),
Returning to the execution of step S2.

FIG. 16 is a flow chart showing details of the scan processing in step S5. As shown in FIG. 16, in step S11, based on the external device capability received by the command signal from the external data processing device 3, the clock generation unit 74 having the configuration shown in FIG.
Determines the frequency of clock 2 generated by. In this embodiment, the frequency of the clock 1 is set to 10 MHz, and the frequency of the clock 2 can be selected from 10 MHz and 2.5 MHz, and the CPU 71 selects either one by the command signal and the selected clock. The clock select signal indicating the frequency of 2 is output to the selector 83 of the clock generator 74. This gives 10
The image data is output based on the 2.5 MHz clock to the external data processing device 3 that cannot be received by the image clock of MHz. It should be noted that in the present embodiment, one of the two types of clocks having different frequencies is used.
Although only the selection of the type of clock is disclosed, one type of clock may be selected from three or more types of clocks each having a different frequency. Next, in step S12, the pulse width of the HD signal, that is, the set value T of the counter of the HD generation unit 85, according to the output size of the image, that is, the effective period of the image in the main scanning direction.
tr and Tle are set, and these data are stored in the HD generation unit 85.
After outputting to the
Turn on the ED.

Then, in this state, in step S14A, the stepping motor M64 is driven to start conveying the original placed on the original tray 11 to the CCD sensor 12, and in step S14B, the original is imaged. It is determined whether or not it has been conveyed to the sensor 12. When it is determined in step S14 that the leading edge of the document has been conveyed to the image sensor 12 (step S1).
4B, YES), in step S15, the front end of the document is conveyed to the image sensor 12 and the image can be read out and output, and the effective range of the image data,
That is, the signal V indicating the effective period in the sub-scanning direction
After outputting SREQ to the data processing device 3, step S
Proceed to 16. On the other hand, the leading edge of the document is the image sensor 12
If not conveyed (N in step S14B)
O), the process returns to step S14A, and the document conveyance is continued.

In step S16 of FIG. 17, the process waits for an image output request and a VSYNC signal indicating that the external data processing device 3 is capturing or receiving an image.
When it is determined in step S16 that the VSYNC signal is input (YES in step S16).
S), step S17 is executed. Next, in step S17, the input of the CPUHSYNC signal is awaited.
When the CPUHSYNC signal is input to the CPU 71, the HSYNC interrupt process shown in FIG. 20 is executed, and the interrupt flag INTF is set to 1 in step S41. Then, the process returns to the scan processing routine of FIG. 17 again, and if it is determined in step S17 that the CPUHSYNC signal is input by the interrupt flag INTF (YES in step S17), step S18.
Then, the interrupt flag INTF is cleared to 0, and it is checked in step S20 whether the image output stop request signal is received from the data processing device 3.

If the image output stop request signal is received from the external data device 3 in step S20 (YES in step S20), the output of the image data is stopped in step S19 and the motor drive signal is turned off. After the rotation of the stepping motor M64 is stopped, the process returns to step S17. Here, the image output stop request signal indicates that the external data processing device 3 cannot receive the image data, and thus requests the scanner printer 1 to stop its operation. When the image output stop request signal is not received in step S20 (NO in step S20), step S21
Based on the output resolution of the image data to be output, it is checked whether the read image data for one horizontal scanning line should be output. That is, the resolution in the sub-scanning direction is 4
When it is lower than 00 dpi, the resolution in the sub-scanning direction is lowered by thinning out the horizontal scanning lines. The determination process of step S21 will be described in detail later.

In the resolution conversion processing, high resolution processing for converting into image data having a higher resolution (for example, 800 dpi in this embodiment) and image data having a lower resolution (for example, 200 dpi in this embodiment) are performed. In the low resolution processing for conversion, the following processing is performed. (1) High resolution processing: The image data of three consecutive lines on the original document are converted into the three FIFO memories 91, 92, 93 of FIG.
23, the image data of three lines are generated at the same time, and the generated image data of each one run is further divided into four lines as shown in FIG. The image data of is processed and output according to the line signal. Therefore, at this time, the operation of the stepping motor M64 is stopped until the image data processing of each divided line is completed. (2) Low resolution processing: At this time, three consecutive documents on the original
The image data of the line is transferred to the FIFO memories 91, 92, 93.
Is written to, but basically HSY in line units
The stepping motor M64 is driven in order to perform the processing by thinning out the NC signal and the image data, but the output of the image data of the lines to be thinned out and removed is prohibited.

As described above, when the image data of the line read in step S21 should not be output (NO in step S21), the control signal is set to low level in step S22 to stop the output of image data. On the other hand, when the image data of the line should be output (YES in step 21), the control signal is set to the high level in step S23 to permit the output of the image data, and then the process proceeds to step S24 in FIG.

In step S24 of FIG. 18, it is determined whether to drive the stepping motor M64 based on the output resolution of the image data to be output. That is, when the resolution specified by the external data processing device 3 (hereinafter referred to as the set resolution or the set dpi) is higher than 400 dpi, the image data of the same line is output a plurality of times with the stepping motor M64 stopped. , Increase the amount of image data. This step S
Details of 24 will be described later. When it is determined in step S24 that the stepping motor M64 is not driven (NO in step S25), step S24
When it is determined that the stepping motor M64 is driven while the motor driving signal is turned off in 25, the stepping motor M64 is driven (YES in step S24), the motor driving signal is turned on and output in step S26. By doing so, the stepping motor M64 is rotated by one step to advance the document by one line in the sub-scanning direction.

After the execution of step S25 or step S26, it is checked in step S27 whether the document has been conveyed to the trailing edge. If not conveyed (NO in step S27), the process returns to step S17 in FIG.

On the other hand, if it is determined in step S27 that the document has been conveyed to the trailing edge (YES in step S27), the output of the VSREQ signal is stopped in step S28, and "white" is output in step S29 in FIG. After outputting the image data of the pixel "," the process proceeds to step S32. This allows the external data processing device 3 to check whether or not the image data is being captured, and if it is, the image data of the "white" pixel can be transmitted. This is because the data amount of the image data output by the scanner printer 1 and the data amount of the image data requested by the external data processing device 3 are different and the image reading system goes down. A process of avoiding a phenomenon such as waiting for data forever, or generating image data corresponding to the amount of image data requested by an external data processing device 3 in the device 3 itself and adding image data of a lacking part This is to avoid doing this. In this embodiment, since the image to be output is a positive image, the image data of the "white" pixel is output in step S29, but the present invention is not limited to this and should be output. When the image is a negative image, preferably
In step S29, the image data of the "black" pixel may be output.

After the execution of step S29, VSYNC
It is determined whether or not the signal input is completed, and if the completion is confirmed (YES in step S32), the output of the image data is stopped, and then the process proceeds to step S30. VSYN
When the input of the C signal is not completed (step S32
In NO), the process of step S29 is continued. Figure 1
In step S30 of 9, after the output of the image data is stopped, it is checked in step S30 whether or not the original document is ejected. If the original document is ejected (YES in step S30), the document irradiation L is performed in step S31.
The ED is turned off, and the processing in the scanner mode is completed.

Next, the resolution conversion processing described in the above-mentioned scanner mode processing will be described in more detail below.

In step S20 of FIG. 17, the image output stop request signal is received from the external data processing device 3. When the process proceeds to step S21, the first read image data of one line is processed as what line. Decide what to do. The image processing method is changed according to the number of lines. As shown in FIG. 23, a method of feeding back the image data of one line to be output to the external data processing device 3 in the process for the image data of the read Nth line out of the image data of the actually read three lines, for example. Is changed to change the image processing method for the image data of the 0th line to the 3rd line of the read Nth line, for example. That is, the weighting coefficient for the (N−1) th line and the Nth line to be added to the image data of the 0th line is set to a value larger than the weighting coefficient for the (N + 1) th line and added to the image data of the 3rd line. The weighting coefficient for the (N + 1) line and the N line to be set is set to a value larger than the weighting coefficient for the (N-1) line.

Further, a specific method of the resolution conversion processing will be described with reference to FIG. Here, the output line outp is used as a variable of the line number to be processed and output.
utline is used, and dpinum is used as a resolution parameter for determining whether to output. The reading resolution of the scanner 1a of the scanner printer 1 of the present embodiment is 400 dpi, which is the reading resolution of 40.
It has a maximum output resolution of 1600 dpi, which is four times the resolution of 0 dpi. Therefore, the scanner printer 1
Is configured so that the image data of one line of read image data can be repeatedly output four times, and the resolution parameter dpinum can be changed in units of 1 dpi.
Is used as follows.

In step S211 of FIG. 21, the processing parameter a is reset to 0 and the output line out
After setting the initial value of putline to 0, step S
In step 212, the setting parameter dpi specified by the command signal from the external data processing device 3 is added to the resolution parameter dpinum for each read line, and this process is performed up to four times (steps S215 and S216). Here, in step S214, the resolution parameter dpi
When num becomes 1600 or more (step S21
YES in step 4), permitting image output, and step S2
In step 17, 1600 is subtracted from the resolution parameter dpinum, and the difference value of the subtraction result is used as the resolution parameter dpinum.
After setting as um, the process proceeds to step S23, and the process related to the image data of the reading line ends. When the processing from step S212 to step S214 is performed four times, the process proceeds to step S22. Note that step S
Resolution parameter dpinu used in 212
m is initialized to 0 in step S1 of FIG.

The stop of the stepping motor M64 is determined as follows. In step 211, the initial value of the output line outputline is reset to 0, and in step S213, the output line outputp
utline is incremented by 1 each time step S212 is executed.

Further, the step S24 of FIG.
, The output line out in step S241.
If it is determined that putline ≧ 4, 4 is subtracted from the current output line outputline in step S242, and the difference value of the subtraction result is output line outputline.
After setting as ne, in step S26 of FIG. 18, the stepping motor M64 is driven and rotated.
In step S241, the output line outputpu is output.
If it is determined that tline <4, step S in FIG.
At 25, the stepping motor N64 is stopped.
The CPU 71 determines whether or not the steps S21 and S28 are performed.
Is performed in synchronization with the CPUHSYNC signal input to the. Next, a concrete example will be given.

(1) When the set resolution is 400 dpi (standard reading resolution), the output line outputline is used in processing the image data of one line of reading.
Changes from 0 → 1 → 2 → 3 → 4 (= 0), the resolution parameter dpinum becomes 0 → 400 → 800 → 1200.
→ 1600 (= 0) and the resolution parameter dpi
When num is 1600 or more, output of image data is permitted. On the other hand, the output line outputline is 4
When the above is reached, the stepping motor M64 is rotated. Thus, when the image output stop request signal from the external data processing device 3 is off, the driving of the stepping motor M64 is always on and the image data is also output.

(2) When the set resolution is 200 dpi,
In the processing of the image data of the first read line (first output line), the output line outputline
Changes from 0 → 1 → 2 → 3 → 4 (= 0), the resolution parameter dpinum becomes 0 → 200 → 400 → 600 →
Since the output line outputline becomes 4 or more in the processing of the image data of the first line to be read, the stepping motor M64 is rotated, but the resolution parameter dpinum does not become 1600 or more and the image data is not output. Next, in the processing of the image data of the second read line (the second output line), the output line outputline is 0 → 1 → 2 → 3.
→ When it changes to 4, the resolution parameter dpinum becomes 8
00 → 1000 → 1200 → 1400 → 1600 (=
It changes to 0). Where the output line outputli
Since ne is 4 or more, the stepping motor M64 is rotated, and the resolution parameter dpinum is 1600 or more, so that image data is output. The above process is repeated in the same manner, and the stepping motor M64 is always turned on, while the image data output is turned off, turned on, ...

(3) When the set resolution is 800 dpi,
In the processing of the image data of the first read line (first output line), the output line outputline changes from 0 → 1 → 2, and the resolution parameter dpinum changes from 0 → 800 → 1600 (= 0), Since the parameter dpinum is 1600 or more, the image data of the current reading line is output, but the output line o
Since the output line does not exceed 4, the driving of the stepping motor M64 is stopped. Next, in the processing of the image data of the second read line (the second output line), the output line outputline is changed from 2 → 3.
→ Changes to 4 (= 0), resolution parameter dpinum
Changes from 0 → 800 → 1600 (= 0) and the resolution parameter dpinum becomes 1600 or more, so that image data is output. Also, the output line outputli
Since ne becomes 4 or more, the stepping motor M64 is driven. The above process is repeated in the same manner, and the driving of the stepping motor M64 is turned off, on, ...
The image data is always output.

Next, the operation of rotating / stopping the stepping motor M64 described above will be described. The image reading apparatus of the present embodiment uses the pulse motor as described above for controlling the document conveyance. In this embodiment, the stepping motor M64 is controlled by a two-phase excitation method as shown in FIGS. CPU71
In response to the drive signal from, the drive signal of each phase is turned on and off at every time t0, so that the speed 1 / t0
At (pps), the stepping motor M64 rotates, and the document is advanced by one line in the sub-scanning direction. Here, the time t0 is the CPUHSYN input to the CPU 71.
It matches the cycle of the C signal.

Further, the driving stop of the stepping motor M64 will be described below. As described above, the CPU 71 controls the rotation / stop operation of the stepping motor M64 in synchronization with the CPUHSYNC signal. That is, when the motor drive signal output from the CPU 71 is in the off state, as shown in FIG.
Reference numeral 4 holds the current phase drive signal but does not output the next phase drive signal to the stepping motor M64. Also,
Similarly, when the CPU 71 receives an image output stop request signal from the external data processing device 3, the rotation of the stepping motor M64 is stopped by not outputting the drive signal of the new phase. At this time, if the image output stop request signal is ON for a certain fixed time such as 50 msec, the drive signals of all the phases are turned OFF.

In this embodiment, the stepping motor M6 is directly based on the motor drive signal from the CPU 71.
4 rotation / stop operation is controlled. However,
The present invention is not limited to this, and the CPU 71 to the resolution conversion unit 7 is used.
5 outputs a control signal such as a line signal to the resolution conversion unit 7
Stepping motor M64 based on the response signal from
The on / off of the drive of may be controlled.

28 to 32 are time charts of each signal in each case in the above-mentioned scanner mode. In FIG. 28, the processing speed of the image data in the data processing device 3 is slow, and every other line, the data processing device 3 is processed.
This is a case where the image output stop request signal is input to the CPU 71 from. Further, in FIG. 29, the selector 83 has a counter 8
This is a case where the second clock signal having a frequency lower than the frequency of the clock 1 is selected as the clock 2 from the first and the second clock signals output from the second clock, and the output resolution is 400 dpi. . Furthermore, FIG.
And 31 are cases where the same clock 2 as the clock 1 is used and the output resolution is 200d respectively.
This is the case for pi and 800 dpi. Furthermore,
FIG. 32 shows the case where the output resolution is 200 dpi,
This is the case where an image output stop request signal is input from the external data processing device 3.

<Printer Mode> When a print request signal is generated in the data processing device 3 as in the scanner mode, a command signal for determining the specifications of the print operation in the laser printer section 1b and print data PVIDEO for determining the actual print content. Is the controller 2 and the control unit 63
It is transmitted to the CPU 71 via the interface unit 67 of. In response to this, the CPU 71 activates the laser printer unit 1b, and sends the synchronization signal HS from the laser printer unit 1b to the horizontal synchronization signal switching unit 68.
The YNCK2 is selected and controlled to be output to the data processing device 3 via the interface section 67 and the controller 2, whereby the print data PVIDEO is synchronized with the synchronization signal HSYNC2 as shown in FIG.
Is sent from the data processing device 3 to the laser drive unit 66 via the controller 2 and the interface unit 67, and the image of the image data PVVIDEO is printed out.

<Copy Mode> In the data processing device 3, as described above, the operation panel 4 is used to set the exposure level and the reading mode for setting one of the character reading mode or the photo reading mode. After making settings in various copy modes of the scanner unit 1a and the laser printer unit 1b, the laser printer unit 1 is activated.
image data read by the scanner unit 1a in synchronization with the horizontal synchronizing signal HSYNCK2 from the laser printer unit 1b.
It is output to b and printed, and the copy process is performed.

[0094]

As described in detail above, according to the image reading apparatus of the first aspect of the present invention, a clock signal having a predetermined frequency is generated and a horizontal synchronizing signal synchronized with the clock signal is generated. A signal generating means for generating, an image reading means for scanning an original image for each scanning line in the main scanning direction in synchronization with the clock signal to read the image and converting the image signal into an image signal, and the image reading in synchronization with the clock signal. Moving means for moving the scanning means and the original image relative to each other in the sub-scanning direction one scanning line at a time, signal output means for outputting the horizontal synchronizing signal and the image signal to an external device, and input from the external device. Receiving means for receiving a stop request signal, and control means for stopping the operation of the moving means and the signal output means in response to the stop request signal received by the receiving means. Provided. Therefore, for example, even when the processing speed of the external device that receives the image signal is slow and the processing cannot follow the image signal due to the difference in the capabilities of the image reading device and the external device, the image signal of the scanning line is changed. Since the output or the stop of the output can be controlled, it becomes possible to receive all the image signals normally without any loss of the image signals by any external device. .

According to the third aspect of the present invention, there are provided the signal generating means for generating a plurality of clock signals each having a different frequency, and the plurality of clock signals input from an external device. Receiving means for receiving a selection signal indicative of selecting one of the:
In response to the selection signal received by the receiving means,
A signal selecting means for selecting and outputting one of a plurality of clock signals generated by the signal generating means, and an original image for each scanning line in synchronization with the clock signal output from the signal selecting means. Image reading means for scanning and reading in the main scanning direction to convert into an image signal, another signal generating means for generating a horizontal synchronizing signal in synchronization with the clock signal output from the signal selecting means, and the horizontal synchronizing And a signal output unit for outputting the signal and the image signal to an external device. Therefore, the image signal can be normally output to the external device without depending on the frequency of the clock signal of the image signal processed by the external device.

Further, according to the image reading apparatus of the fourth aspect of the present invention, signal generating means for generating a clock signal having a predetermined frequency and a horizontal synchronizing signal synchronized with the clock signal, An image reading unit that scans and reads an original image in the main scanning direction for each scanning line in synchronization with the clock signal and converts the image into an image signal; and the image reading unit and the original image that are synchronized with each other in synchronization with the clock signal. A moving means for moving one scanning line at a predetermined moving speed relatively in the sub-scanning direction, a signal output means for outputting the horizontal synchronizing signal and the image signal to an external device, and an input from the external device. Receiving a high resolution signal indicating that the image signal to be output has a predetermined high resolution or a low resolution signal indicating that the image signal to be output has a predetermined low resolution Receiving means, first control means for controlling the moving speed of the moving means in response to the high resolution signal received by the receiving means so that the image signal has a predetermined high resolution; In response to the low resolution signal received by the receiving means, the image signal has a predetermined low resolution, and the horizontal sync signal is thinned out at a rate corresponding to the low resolution signal and output. Second control means for controlling the means. Therefore, the image reading apparatus outputs the image signal after converting the resolution of the image signal to be output to the resolution of the image of the image signal corresponding to the resolution signal. An image signal can be normally output to an external device without depending on the resolution.

Further, according to the image reading apparatus of the fifth aspect of the present invention, the first signal for generating a clock signal having a predetermined frequency and a horizontal synchronizing signal synchronized with the clock signal. Generating means, image reading means for scanning an original image in the main scanning direction for each scanning line in synchronization with the clock signal, reading the converted image into an image signal, and the image reading means and the original in synchronization with the clock signal. Moving means for moving the image relative to each other one scanning line at a predetermined moving speed and in the sub-scanning direction, signal output means for outputting the horizontal synchronizing signal and the image signal to an external device, and the clock signal. In synchronization with the second signal generating means for generating an internal sub-scanning effective signal indicating an effective area of the image signal in the sub-scanning direction, and input from the external device to the external device. Receiving means for receiving an external sub-scanning valid signal indicating an effective area in the sub-scanning direction of a processable image signal, the internal sub-scanning valid signal being generated by the second signal generating means, and the external sub-scanning. First control means for controlling the signal output means so that the image signal is output when the valid signal is received by the receiving means; and the internal sub-scanning valid signal for the second signal generating means. Is not generated by the external sub-scanning valid signal and is being received by the receiving means,
Second control means for controlling the signal output means so that a predetermined image signal is output. Therefore, when the external device is receiving an image signal, even if there is no image signal to be output from the image reading device, a predetermined image signal is transmitted in response to the external sub-scanning valid signal. Since the image signal is output to the external device, it is possible to receive the image signal normally in any external device without loss of the image signal.

[Brief description of drawings]

FIG. 1 is a block diagram of an image reading system including a scanner printer, a controller, and a data processing device, which is an embodiment according to the invention.

FIG. 2 is a plan view of an operation panel of the scanner printer of FIG.

FIG. 3 is a vertical sectional view showing the structure of the scanner printer of FIG.

FIG. 4 is a perspective view showing a structure of an optical system of the scanner printer of FIG.

5 is a block diagram showing a configuration of the image reading system in FIG. 1. FIG.

6 is a block diagram showing a configuration of an electric circuit of the scanner printer of FIG.

7 is a block diagram of the clock generator of FIG.

8 is a timing chart showing the relationship between the SH signal and the HD signal generated by the clock generator of FIG.

9 is a block diagram of a 3-line buffer memory which is a part of the resolution conversion unit of FIG.

10 is a block diagram of a resolution conversion processing unit that is a part of the resolution conversion unit in FIG.

11 is a timing chart showing the operation of the resolution conversion processing unit of FIG.

12 is a block diagram showing a configuration of a binarizing unit in FIG.

13 is a block diagram of the interface gate circuit of FIG.

FIG. 14 (a) shows that the frequency of clock 1 is clock 2
6B is a timing chart showing the relationship among the clock 1, the clock 2, the SH signal, the HD signal, and the HSYNC signal when they match the frequency of FIG.
6 is a timing chart showing the relationship among the clock 1, the clock 2, the SH signal, the HD signal, and the HSYNC signal when the frequency of 1 does not match the frequency of the clock 2.

15 is a flowchart showing a scanner mode main routine executed by the control unit 63 of FIG.

16 is the first part of the flowchart of the scan processing subroutine in FIG. 15. FIG.

FIG. 17 is the second part of the flowchart of the scan processing subroutine shown in FIG. 15;

FIG. 18 is a third part of the flowchart of the scan processing subroutine shown in FIG. 15;

FIG. 19 is a fourth part of the flowchart of the scan processing subroutine in FIG. 15;

20 is an HS executed by the control unit 63 of FIG. 6;
9 is a flowchart of YNC interrupt processing.

FIG. 21 is a flowchart showing details of the process of step S21 of FIG.

FIG. 22 is a flowchart showing details of the process of step S24 of FIG.

23 is a plan view showing each reading scanning line and each pixel on the scanning line after conversion, which shows a resolution converting process in the resolution converting unit of FIG. 6. FIG.

FIG. 24 is a circuit diagram showing a drive circuit of the stepping motor of FIG.

FIG. 25 is a timing chart showing each control signal when performing two-phase excitation of the stepping motor of FIG. 24.

FIG. 26 is a timing chart showing each control signal when the rotation of the stepping motor is stopped in response to the image output stop request signal.

FIG. 27 is a timing chart showing the relationship between the HSYNCK2 signal and image data in the printer mode.

FIG. 28 is a timing chart showing the relationship between signals at random stop in the scanner mode.

FIG. 29 is a timing chart showing the relationship between signals in the scanner mode when the clock has a low frequency.

FIG. 30 is a timing chart showing the relationship of each signal when converting to a low resolution in the scanner mode.

FIG. 31 is a timing chart showing the relationship of each signal when converting to high resolution in the scanner mode.

FIG. 32 is a timing chart showing a relationship between signals when a low resolution is converted in the scanner mode and an image output stop request signal is input.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Scanner printer, 1a ... Scanner part, 1b ... Laser printer part, 2 ... Controller, 3 ... Data processing device, 3a ... Display, 4 ... Operation panel, 12 ... Line type CCD image sensor, 62 ... Image processing part, 63 ... control unit, 64 ... scanner mechanism unit, 65 ... printer mechanism unit, 66 ... laser drive unit, 67 ... interface unit, 71 ... CPU, 72 ... ROM, 73 ... RAM, 74 ... clock generation unit, 75 ... resolution conversion unit , 76 ... Binarizing unit, 77 ... Interface gate circuit, 78 ... Input / output unit, 81 ... Signal generator, 82 ... Counter, 83 ... Selector, 84 ... SH generating unit, 85 ... HD generating unit, G1 to G5 ... Nand gate, M64 ... Stepping motor.

Continuation of the front page (31) Priority claim number Japanese Patent Application No. 3-77622 (32) Priority date 3 (1991) April 10 (33) Priority claim country Japan (JP)

Claims (6)

[Claims] 1. A signal generating means for generating a clock signal having a predetermined frequency and a horizontal synchronizing signal synchronized with the clock signal, and a main scanning of an original image for each scanning line in synchronization with the clock signal. Image reading means for scanning and reading in a direction and converting into an image signal, and moving means for moving the image reading means and the original image relative to each other in the sub-scanning direction by one scanning line in synchronization with the clock signal. Signal output means for outputting the horizontal synchronizing signal and the image signal to an external device, receiving means for receiving a stop request signal input from the external device, and the stop request signal received by the receiving means. An image reading apparatus comprising: a control unit that responds to stop the operations of the moving unit and the signal output unit. 2. The image reading device further comprises another receiving means for receiving a resolution signal input from the external device and indicating a resolution of an image signal to be output, wherein the signal output means is the horizontal synchronizing signal. The image reading apparatus according to claim 1, wherein the image is read out by thinning out at a rate corresponding to the resolution signal. 3. A signal generating means for generating a plurality of clock signals each having a frequency different from each other, and a selection signal inputted from an external device and indicative of selecting one of the plurality of clock signals. Receiving means, and in response to the selection signal received by the receiving means,
A signal selecting means for selecting and outputting one of a plurality of clock signals generated by the signal generating means, and an original image for each scanning line in synchronization with the clock signal output from the signal selecting means. An image reading means for scanning and reading in the main scanning direction to convert into an image signal, another signal generating means for generating a horizontal synchronizing signal in synchronization with the clock signal output from the signal selecting means, and the horizontal synchronizing An image reading apparatus comprising: a signal and a signal output unit that outputs the image signal to an external device. 4. A signal generating means for generating a clock signal having a predetermined frequency and a horizontal synchronizing signal in synchronism with the clock signal, and an original image in main scanning for each scanning line in synchronism with the clock signal. Image scanning means for scanning and reading in the direction to convert the image signal into an image signal, and the image scanning means and the document image in synchronization with the clock signal, one scanning line at a predetermined moving speed and in the sub-scanning direction. And a signal output means for outputting the horizontal synchronizing signal and the image signal to an external device, and showing that the image signal to be output inputted from the external device has a predetermined high resolution. Receiving means for receiving a high resolution signal or a low resolution signal indicating that the image signal to be output has a predetermined low resolution, and the high resolution received by the receiving means. In response to the degree signal, the first control means for controlling the moving speed of the moving means so that the image signal has a predetermined high resolution, and the low resolution signal received by the receiving means. And a second control means for controlling the signal output means so that the image signal has a predetermined low resolution and the horizontal synchronizing signal is thinned out and output at a rate corresponding to the low resolution signal. An image reading device characterized by the above. 5. A first signal generating means for generating a clock signal having a predetermined frequency and a horizontal synchronizing signal synchronized with the clock signal, and an original image for each scanning line in synchronization with the clock signal. An image reading means for scanning and reading in the main scanning direction and converting it into an image signal; and the image reading means and the original image in synchronization with the clock signal at a predetermined moving speed relative to each other one scanning line at a time. Moving means for moving in the sub-scanning direction, signal output means for outputting the horizontal synchronizing signal and the image signal to an external device, and an effective area in the sub-scanning direction of the image signal in synchronization with the clock signal are shown. Second for generating internal sub-scanning valid signal
Signal receiving means for receiving an external sub-scanning valid signal indicating an effective area in the sub-scanning direction of an image signal which is input from the external device and can be processed by the external device, and the internal sub-scanning valid signal. First control means for controlling the signal output means so as to output the image signal when the external sub-scanning valid signal generated by the second signal generating means and the external sub-scanning valid signal is received by the receiving means. A predetermined image signal is output when the internal sub-scanning valid signal is not generated by the second signal generating means and the external sub-scanning valid signal is received by the receiving means. An image reading apparatus comprising: a second control unit that controls a signal output unit. 6. The image reading apparatus according to claim 5, wherein the predetermined image signal is an image signal indicating a white or black pixel.