JPH1070640A - Electronic blackboard equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic blackboard equipment having a practical recording speed in which multi-color print is also available. SOLUTION: In the relation between a pulse width of a strobe signal fed to a thermal head to form an image on multi-color thermosensing recording paper and coloring of the multi-color thermosensing recording paper, the multi- color thermosensing recording paper is colored in black in a range of pulse width of (a) to (b), and the multi-color thermosensing recording paper is colored in red in a range where the pulse width is (c) or over. Furthermore, a red coloring layer is not stimulated in the multi-color thermosensing recording paper to cause red color recognition in the range of the pulse width from (a) to (b) but the multi-color thermosensing recording paper is colored in an intermediate color between the red and black colors, that is, in brown. Thus, at first data resulting from ORing a black image and a red image are recorded and then data of the red image are recorded so as to record an image in three colors of white, black, red and the pulse width of the 2nd strobe signal is reduced in the case of recording the red image.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a method for optically identifying and reading contents written in a first color and a second color in the same writing screen area, respectively.
The content of the writing screen content is printed on the base layer by printing the discrete levels of heat corresponding to the color and the second color on a pixel-by-pixel basis. The present invention relates to an electronic blackboard device for recording on a multicolor recording thermosensitive recording paper in which B-color developing layers corresponding to a second color are sequentially laminated.

[0002]

2. Description of the Related Art In recent years, a multicolor thermosensitive recording apparatus capable of recording an image in a plurality of colors using a multicolor thermosensitive recording paper having a plurality of coloring layers laminated thereon has been put to practical use.

For example, if a multicolor thermal recording apparatus capable of recording a red image in addition to black and white is applied to a plotter of a facsimile apparatus, a red underline is added to an emphasized portion, or a red mark is added or emphasized. A document in which characters are written in red can be transmitted as it is, so that more effective image information transmission can be performed. Also, if such a multicolor thermal recording device is used for a so-called electronic blackboard device,
The minutes and the like can be recorded and output more effectively.

As shown in FIG. 26, a multi-color thermal recording paper for recording black-and-white and red images is a base paper PB as shown in FIG.
On S, a red coloring layer RYR for emitting red, black decoloring waste RYE for removing black, a black coloring layer RYB for emitting black,
Further, it is formed by laminating a protective layer RYP.

When a heating resistor HT having a contact surface having a size corresponding to a pixel is heated while being brought into contact with the protective layer RYP, a sufficient amount of heat is supplied to the protective layer RYP and the black coloring layer RYB. The black coloring layer RYB develops a color in the area corresponding to the pixel, and a black pixel is recorded. When the amount of heat is further supplied, the black color erasing layer RYE acts to erase the developed black color and further supply the amount of heat. The red coloring layer RY
R is colored and a red pixel is recorded.

In this manner, a black pixel or a red pixel is recorded. The amount of heat (energy) required to record a red pixel is several times (for example, about three times) the amount of heat required to record a black pixel.

As described above, an image recording apparatus that records an image of a different color (saturation, color tone) or density in units of pixels by applying different levels of energy is, as described above, a multi-color thermosensitive image. Various proposals have been made in addition to the multicolor thermal recording apparatus using recording paper. For example, there is one in which the area of a pixel is set according to the energy level.

In the above-described multi-color thermal recording apparatus, a thermal head having a configuration in which a predetermined number of heating elements (heating resistors) having dimensions corresponding to pixel dimensions, which are components of an image, are arranged in a straight line. Used as
By driving the heating resistor of the thermal head to generate heat corresponding to the image of one line and moving the multicolor thermal recording paper relative to the direction perpendicular to the arrangement direction of the thermal head,
Images are recorded on multicolor thermal recording paper.

If the recording density of the thermal recording apparatus is, for example, 8 dots / mm and the recording width is 216 mm of A4, the number of heating resistors required for the thermal head in this case is 1,728. . Further, the thermal head is usually configured as one element, and the wiring to each heating resistor is realized by printed wiring.

When such a thermal head is driven at a time, a large-capacity power supply capable of driving a maximum of 1,728 heating resistors at the same time is required. Since it is not possible to supply such a large amount of current at a time, the thermal head is usually divided into a plurality of blocks, and power is supplied to each of the blocks sequentially to reduce the power supply capacity and supply the power at once. The current can be reduced.

For example, the thermal head is divided into eight blocks so that an image can be recorded for each block, and an example is shown in FIG.

This thermal head has shift registers 1 and 1 for inputting recording data DT for one line.
A latch circuit 2 for storing the recording data DT for one line is provided, and the recording data DT for the next line can be input while recording the data for one line, so that the printing processing speed is increased. be able to. CK is a clock signal for inputting the recording data DT to the shift register 1.

The output of each digit of the latch circuit 2 is provided by k gate circuits GT for driving k heating resistors HT1 to HTk.
1 to GTk, respectively.

The strobe signals STB1 to STB8 are applied to the other input terminals of the gate circuits GT1 to GTk via m (= k / 8) inverters IN1 to IN8, respectively.

Here, similarly to the above-described example, the recording width is set to A4.
Assuming that the size and the recording density are 8 dots / mm, k is 172.
8, and m becomes 216.

Therefore, strobe signals STB1-SB
During the period when TB8 falls to the logical level L, the heating resistor HT1 of the bit of which the content of the recording data DT is "1" is set.
HTk are turned on, and an image is recorded.

The strobe signals STB1 to STB8
Are determined by the number of divisions of the thermal head, and one example is shown in FIGS. 28 (a) to (k).

In FIG. 1, a period T1 is a case where the thermal head is divided into eight, a period T2 is a case where the thermal head is divided into four, a period T3 is a case where the thermal head is divided into two, and a period T4 is a case where simultaneous printing is performed. The time required to record data is shown. Naturally, the smaller the number of divisions, the shorter the time required to record one line of data.

Therefore, when it is necessary to increase the recording speed as much as possible, the number of divisions is set to two.

The heat value J generated by the heating resistor is expressed by the following equation (I).

J = P · t (I)

Here, P is the amount of heat generated by one heating resistor per unit time, and t is the time during which the heating resistor is driven, that is, the pulse width of the strobe signal.

Therefore, as described above, when recording black and red pixels on multicolor thermal recording paper, the amount of heat required for recording red pixels is about three times that required for recording black pixels. For example, when recording a black-and-white red image, as shown in FIGS. 29A to 29D, the width of the strobe signal is changed to a black (black-and-white) image when a red (red / non-red) image is recorded. May be set to be about three times as large as when recording is performed.

Here, the width c of the strobe signal at the time of recording a red / non-red image corresponds to the minimum amount of heat required for the multicolor thermosensitive recording paper to develop a red color. The width a of the strobe signal at the time of recording corresponds to the minimum amount of heat required for the multicolor thermal recording paper to develop black (see FIG. 1).

On the other hand, the life N of the thermal head is expressed by the following equation (II).

N = A · exp (P, −i) · exp (t, −j) · exp (T, −k) (II)

Here, A is a coefficient, T is a repetition period of a strobe signal, i is 25 to 20, and j is 18
-12 and k are 6-2. These constants are determined depending on the type of the thermal head and the like. Also,
The operator exp (x, y) is an operator representing the radix x to the power y (power).

[0028]

As described above, the life of the thermal head increases as the heat generation amount per unit time of the heating resistor and the continuous driving time (ie, the pulse width of the strobe signal) increase. Functionally shorten.

Therefore, when a red image is recorded by a multi-color thermal recording apparatus, if the thermal head is continuously driven for a time three times as long as that of recording a black-and-white image as described above, the life of the thermal head becomes longer. Therefore, the thermal head cannot be directly driven directly for such a long time.

Therefore, conventionally, when a red image is recorded, a necessary amount of heat is applied by repeatedly heating the same line a plurality of times in a short time such that the life of the thermal head is maintained to some extent.

From the above, in the conventional electronic blackboard apparatus using such a multi-color thermal recording apparatus, the time for recording a red image is extremely long, and it has been difficult to put it to practical use. .

The present invention has been made in view of such circumstances, and it is an object of the present invention to provide an electronic blackboard apparatus capable of printing in multiple colors and having a practical recording speed.

[0033]

According to the present invention, the contents described in a first color and a second color are optically identified and read in the same writing screen area, and the first color and the first color are read. By printing the discrete level of heat corresponding to the second color in pixel units,
An electronic blackboard apparatus for recording on a multicolor recording thermosensitive recording paper in which an A-color coloring layer corresponding to the first color, a decoloring layer, and a B-color coloring layer corresponding to the second color are sequentially laminated on a base layer, Synthesizing means for synthesizing the description content of the first color corresponding to the high-level heat quantity with the description content of the second color corresponding to the low-level heat quantity; the synthesis content synthesized by the synthesis means; A storage means for storing the description contents described in colors is provided. When recording the contents described in the first color and the second color in the A color and the B color, respectively, Reading out the combined content and the description content described in the first color from the storage means, applying a low-level heat to the combined content to develop the B color, The above description is higher than the content described in color. From heat Le by applying the amount of heat corresponding to the difference between the low level of heat, after erasing the recorded contents that are colored by the B color, it is obtained so as to develop color by the A color.

[0034]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
An embodiment of the present invention will be described in detail.

First, the principle of the present invention will be described.

For example, when an attempt is made to record a black-and-white image using the above-described multicolor thermosensitive recording paper, the pulse width of the strobe signal applied to the thermal head for forming an image on the multicolor thermosensitive recording paper is determined by the following equation. The relationship with the color development of the multicolor thermal recording paper is as shown in FIG.

That is, when the pulse width is in the range of a to b, the multicolor thermosensitive recording paper is colored black, and when the pulse width is c or more, the multicolor thermosensitive recording paper is colored red. When the pulse width is in the range of b to c, the red coloring layer of the multi-color thermosensitive recording paper does not act until the color is recognized as red, and an intermediate color between black and red, that is, brown is developed.

Here, since the thermal conductivity of the multicolor thermal recording paper is not so high and the time from when a black pixel is recorded to when a red pixel is recorded is very short, the black pixel is recorded. During the time from when the black pixel is printed until the time when the red pixel is printed, the portion corresponding to the pixel heated when the black pixel is printed substantially holds the amount of heat for printing the black pixel.

Further, since the color forming process in the multicolor thermosensitive recording paper is based on the chemical reaction of each layer, it is not necessary to supply the heat once supplied again. That is, when a heat amount necessary for causing red color to be applied is applied to a black color portion, the portion is colored red.

From these facts, the present inventor records, for each line, first the data of the result of the logical OR of the black image and the red image, and then records the data of the red image, whereby the black and white and red images are recorded. It has been found that a three-color image can be recorded, and the pulse width of the second strobe signal for recording a red image can be reduced.

That is, in this case, the pulse width of the second strobe signal when recording the red image data is represented by the pulse width a when the data resulting from the logical OR of the black image and the red image is recorded. Then, (c−a) is obtained, which is much smaller than when the red image data is recorded alone,
Further, even if the voltage is applied at one time, the life of the thermal head can be obtained to a certain value or more.

Therefore, according to such a recording method,
The time required for recording black-and-white and red three-color images can be greatly reduced, and a practical multicolor thermal recording apparatus can be realized.

According to the above equation (II), the life of the thermal head decreases exponentially with respect to the pulse width of the strobe signal. If the pulse width of each strobe signal is set to c / 2 when recording the data as a result of the logical OR of the images and then when recording the data of the red image, the life of the thermal head becomes the longest.

However, the pulse width of the strobe signal is c
In the case of / 2, since this pulse width is larger than the limit pulse width b at which the color is developed as black, the black image is undesirably colored brown.

Therefore, the pulse width of the strobe signal when recording the data resulting from the logical sum of the black image and the red image is defined as
By setting the pulse width b at which the color develops as black as the limit and setting the pulse width of the strobe signal when recording data of only the red image to (c−b), the black image can be appropriately recorded and the thermal image can be recorded properly. The life of the head can be maximized.

FIG. 2A to FIG. 2C show the recording state when the recording by the thermal head is performed in two divisions under such conditions.
(D). The thermal head in this case has the same configuration as that shown in FIG.

As described above, the image corresponding to the lower level of heat is recorded sequentially from the image corresponding to the lower level of heat, and the image corresponding to the lower level of heat is added to the image corresponding to the lower level of heat. When the image corresponding to the calorific value is included in pixel units to form the recording data of the image corresponding to the lower calorific value, and when the image corresponding to the caloric value of the quotient level is to be recorded, the shortage may be reduced. By applying a corresponding amount of heat, the recording speed in an image recording apparatus that records an image composed of pixels of various levels can be remarkably improved.

In the above description, a multi-color thermal recording apparatus for recording images of a plurality of colors using multi-color thermal recording paper has been described. However, the present invention is applicable to other apparatuses. Can be applied to

For example, by applying a plurality of levels of heat, the size of a dot (or the size of a pixel) occupying the area of a pixel of a predetermined size is recorded in a size corresponding to each level. For recording devices,
Can be applied.

The present invention can be applied to a case where the applied energy is other than heat.

Now, FIGS. 3A to 3D and FIG.
1 shows an example of an electronic blackboard device according to an embodiment of the present invention. This electronic blackboard device can record and output three-color images of black and white and red.

In the figure, a sheet 1 for writing an image composed of characters, figures, and the like is wound at both ends around paper tubes 2 and 3 housed in the main body, and has a front board 4 on the back. The recording surface is flattened in contact with the recording medium.

The image recorded on the sheet 1 is illuminated by a fluorescent lamp 5 inside the main body, and the reflected light is transmitted through a mirror 6.
Images are formed on the line image sensors 9 and 10 by the lenses 7 and 8.

Both sides of the main body of the electronic blackboard device are provided with legs 1
And an operation display unit 13 for operating the electronic blackboard device.
Are arranged.

The printer 14 for recording and outputting the contents of the cardboard is attached to the back of the main body, and the recording paper on which the image is recorded is discharged to a tray 15.

At positions immediately before the lenses 11 and 12 for forming images on the line image sensors 9 and 10, a red filter 16 for transmitting a red component of the image and a cyan component for a complementary color component of red are transmitted. Cyan filter 1
7 are arranged, whereby the red component of the image is formed on the line image sensor 9 and the cyan component of the image is formed on the line image sensor 10. As a result, the image is output from the line image sensor 9. And the line image sensor 10 outputs an image signal corresponding to the cyan component of the image.

The outputs of the line image sensors 9 and 10 are processed for each of the same addresses in the main scanning as described later to identify black and white and red images. Note that, of course, the line image sensors 9 and 10
The optical system and the line image sensors 9 and 1 for equalizing the position of the reading width and the magnification (reduction ratio) of the lenses 11 and 12 so that the same image can be read.
The position of 0 is adjusted.

The red filter 16 has, for example, a spectral characteristic as shown by a broken line in FIG.
Has spectral characteristics as shown by the solid line in FIG. Thus, these red filter 16 and cyan filter 1
7 are not completely complementary to each other, but red can be identified by a method described later.

A component in a wavelength region where the characteristics of the red filter 16 and the characteristics of the cyan filter 17 shown in FIG. 4 intersect cannot be read as a so-called dropout color. If a ruled line (length and width) is drawn on the sheet 1 using the color serving as the dropout color, the convenience of the writer can be obtained. For example, in this case,
A ruled line is formed on the sheet 1 in yellow or orange.

FIGS. 5A to 5D show an example of the printer 14. FIG.

In the figure, a roll-shaped multicolor thermal recording paper 2
No. 0 has the same structure as that shown in FIG. 25, and can record black-and-white and red three-color images.

The multicolor thermal recording paper 20 is inserted into the gap between the thermal head 21 and the platen roller 22, and an image is recorded by the thermal head 21 while being conveyed at a constant speed by the platen roller 22, and the recording of the image is completed. Then, it is cut by the cutter 23, and the cut portion is guided to the tray 15 (not shown) via the guide plate 24.

The shaft of the platen roller 22 is connected to a pulley 25 via a one-way clutch which engages in the counterclockwise direction A and slides in the clockwise direction 8.
5 and a pulley 26 for driving the cutter 23 include:
Timing belt 2 for transmitting the power of motor 27
8 are installed.

A link 29 for driving the cutter 23 is attached to the pulley 26 via a one-way clutch that slides in a counterclockwise direction and engages in a clockwise direction B. One end of 29
The photo interrupter 30 is turned on and off.

Therefore, when the motor 27 is driven in the counterclockwise direction A, the platen roller 22 rotates and the multicolor thermosensitive recording paper 20 is conveyed. In this case, link 2
9 does not move, and therefore, the photo interrupter 30 remains off (see FIG. 4C).

When the motor 27 is driven in the clockwise direction B, the multicolor thermosensitive recording paper 20 stops because the platen roller 22 stops. At this time, the link 29 moves and the cutter 23 operates, whereby the multicolor thermal recording paper 20 is cut. Further, the photo interrupter 30 is turned on while the link 29 is moving and the cutter 23 is operating, and when the pulley 26 makes one rotation and the link 29 returns to the original position, the photo interrupter 30 is turned off (FIG. 3). (D)).

Accordingly, the motor 27 is moved in the clockwise direction B
When the multicolor thermosensitive recording paper 20 is cut, the photointerrupter 30 is turned on. When the cutter 23 completes cutting the multicolor thermosensitive recording paper 20, the photointerrupter 30 is turned off again.
By monitoring the output of 0, the end of the process can be determined.

The sheet sensor SS is for detecting that the multi-color thermal recording paper 20 is sufficient, and the feed switch FD is for manually operating the multi-color thermal recording paper 20 when the roll is replaced. It is for moving with.

FIG. 6 shows an example of the operation display section 13.

In the figure, the current screen display 31
Displays the screen number of the sheet 1 currently set on the plate surface, and the target screen display 32
The screen number of the target to be moved is displayed.
Can be changed by a feed key 33 for moving the sheet 1 in the forward direction and a return key 34 for moving the sheet 1 in the reverse direction. In this embodiment, the number of readable screens is set to four.

The lamps 35, 36, 37, and 38 operate in a screen memory mode for recording and outputting stored images, a two-page mode for recording and outputting an image of two pages (screen) to one page, and a four-page mode. Display that the four-page mode for reducing and printing the image of one minute into one page and the long mode for continuously recording and outputting the image of four pages without reducing the size are selected. The mode is selected by the screen continuous shooting key 39. Each time the screen continuous shooting key 39 is turned on, the lamps 35, 36, 37, and 38 are cyclically lit, and the lit lamps 35 and 3 are turned on.
Modes corresponding to 6, 37 and 38 are selected.

When the two-page mode and the four-page mode are selected, the image is reduced when reading the image. When the long mode is selected, the image is read and the printer 14
To record and output.

A lamp 40 indicates that a date copy mode for adding a date to an image and recording and outputting the selected image is selected. A lamp 41 is a date set mode for setting a clock circuit in the electronic blackboard device. Indicates that is selected. The date key 42 is for selecting a date copy mode or a date set mode. That is, when the date key 42 is turned on for a predetermined time or more, the date set mode is selected.
When the ON state of No. 2 is stopped within a predetermined time, the date copy mode is selected by toggle.

The lamps 43, 44, 45 and 46 are a black / red mode for recording and outputting black / red images in respective colors, and an all black mode for recording and outputting all images in black (ie, red images are also black). This mode indicates that the red-erase mode, in which the image is recorded and output with the red part deleted, and the black-erase mode, in which the image is recorded and output with the black part deleted, are selected. is there. These recording color modes are selected by the copy color key 47. Each time the copy color key 47 is turned on, the lamps 43, 44, 45, 46 are cyclically lit, and the lit lamps 43, 44, 45 are lit. , 46
Is selected.

When the date setting mode is selected, the lamps 43, 44, 45, and 46 indicate items to be corrected, that is, "month", "day", "hour", and "minute".
If none of the lamps 43, 44, 45, 46 is lit, "year" is selected as the item to be corrected.

A lamp 48 indicates that a mode for increasing the copy density is selected, and this mode is toggled every time the key 49 is turned on.

The display 50 indicates the number of recording papers (multicolor thermal recording green paper) to be recorded and output. Every time the plus key 51 is turned on, the display content of the display 50 increases by one. Each time the minus key 52 is turned on, the display 5
The display contents of "0" decrease by one.

When the date setting mode is selected, the contents of the item to be corrected (numerical value) are displayed on the display 50.
Is displayed, and can be similarly changed by the plus key 51 and the minus key 52.

The clear / stop key 53 is used as a clear key for clearing data displayed on the display 50 when the electronic blackboard device is not operating, and when the electronic blackboard device is operating. Act as a stop key to stop each.

A start key 54 is for starting the operation of the electronic blackboard device, and a power switch 55 is for turning on or off the power of the electronic blackboard device.

The error indicator 56 indicates that the key counter has not been set, and the error indicator 57 indicates that the multicolor thermal recording paper 20 has run out. The display 58 indicates that the copying operation cannot be performed for some reason, and the status display 59 indicates that the copying operation is possible.

FIG. 7 shows an example of a control system of the electronic blackboard device.

In the figure, the sensor driving / image signal processing units 61 and 62 include line image sensors 9 and 10, respectively.
And receives an image signal RA corresponding to the red component of the image output from the line image sensor 9 and an image signal BA corresponding to the cyan component of the image of the image output from the line image sensor 10, and Are converted into digital image signals RD and BD having a predetermined number of bits and output to the color recognition circuit 63.

The color recognition circuit 63 calculates the sum and difference of the received digital image signals RD and BD for each main scanning address, determines the brightness of the pixel based on the sum data, and determines the brightness based on the difference data. The color saturation of the pixel is determined, and based on a combination of the lightness determination result and the saturation determination result, it is determined whether the pixel is a black pixel, a white pixel, or a red pixel. In the case of a pixel, the black signal SB and the red signal SR are set to 1, 0, respectively, in the case of a white pixel, both the black signal SB and the red signal SR are set to 0, and in the case of a red pixel, the black signal SB and the red signal SR are set. Are set to 0 and 1, respectively, and these black signal SB and red signal SR are output to the color combining / erasing circuit 64.

The color synthesizing / erasing circuit 64 is for forming black recording data BV and red recording data RV for recording an image corresponding to the color mode of the recorded image. That is, as described above, when recording an image in three colors of black and white and red, data of the logical sum of the black and white image and the red / non-red image (that is, black recording data BV) is first recorded on the same line. Second, since the data of the red / non-blush image (ie, the red recording data RV) is recorded for the second time, the black signal SB and the red signal SR input from the color recognition circuit 63 in the pixel order correspond to the black signal. Recording data BV and red recording data RV are formed for each pixel. These black recording data BV and red recording data RV are output to the erasing circuits 65 and 66, respectively.

As described above, the color synthesizing / erasing circuit 64
Is provided immediately before the recording data is stored in the memory (described later) because the recording data is stored in the data memory 65 and the logic operation of the microprocessor used as the CPU (central processing unit) 66 is performed. This is because if the black recording data BV and the red recording data RV are formed, it takes a long processing time, and it is difficult to realize high-speed image recording.

The erasing circuits 67 and 68 are used to cut the images at both ends of the recording width by a predetermined number of pixels and convert the portions to white images. That is, in consideration of the finished copy, it is easier to see a blank portion formed around the image than to form an image over the entire recording width.
Further, since black streaks and the like may appear in the image at the end of the reading width, it is preferable to cut the images at both ends of the recording width.

The black recording data BVc and the red recording data RVc output from the erasing circuits 67 and 68 are output to the serial / parallel converters 69 and 70, respectively.

The serial / parallel converters 69 and 70
This is for converting the black recording data BVc and the red recording data RVc into parallel signals of a predetermined number of bits (bit width of a data bus in a system bus (described later)) for storage in the data memory 65. The black recording data BVc and the red recording data RVc are stored in the data memory 65.
A DMA (direct memory access) controller 71 is used to transfer the output data of the serial / parallel converters 69 and 70 to the data memory 65 in order to execute the process of storing the data in real time. It is realized without intervention.

The data memory 65 stores black recording data BVc.
And red recording data RVc for each page of an image (one screen). Note that the black recording data BVc and the red recording data RVc are collectively accumulated in different areas.

The CPU 66 has a program memory 72 storing a program for the control processing to be executed and a work memory 73 used for a work area.
Each unit is connected via a system bus 74 including a data bus, an address bus, and a control bus.

Further, a sheet motor for exchanging various data with the operation display unit 13, inputting output data of various sensors and switches (sensor / switch group 75), and moving the sheet 1 in the forward and reverse directions. 76,7
7 and the output of the drive signal to the motor 27 of the printer 14 are
This is performed via the input / output circuit 78. The sensor switch group 75 includes a sheet sensor for detecting the movement of the sheet 1. The CPU 66 determines the screen number of the sheet being used by referring to the output of the sheet sensor. You.

The pulse generating section 79 includes a line synchronizing signal LNSYN indicating the start of a read cycle of one line, and clock signals ELCK and ELC for setting read timing for each pixel from the line image sensors 9 and 10.
K2, and a line synchronization signal LNSYN
Are connected to the sensor driving / image signal processing units 61 and 62 and the simultaneous reading / thermal head interface unit (described later) 80,
The clock signal ELCK is supplied to the sensor driving / image signal processing unit 6
Clock signals ELCK2 are applied to sensor drive / image signal processing units 61 and 62, respectively.

The input / output circuit 81 outputs a control signal from the CPU 66 to the pulse generator 79, and
6 for generating a control signal output by the control unit 6, that is, mode signals MD0 and MD1 for setting a color mode and a data valid signal DTEN indicating an effective pixel section of a reading width. The mode signals MD0 and MD1 are color signals. The data valid signal DTEN is supplied to the combining / erasing circuit 64 by the erasing circuits 67 and 68 and the serial / parallel converter 6.
9,70.

The pulse generator 82 generates the clock signal CLK
2 and a clock signal 2ELCK obtained by dividing the frequency of the clock signal CLK2 by 2 at its falling timing.
CK is added to a parallel / serial conversion / memory access unit (described later) 83.

The input / output circuit 84 outputs a control signal from the CPU 66 to the pulse generator 82,
6, a control signal output from the DMA controller 71, that is, a print enable signal EP indicating an effective period of image recording, a reset signal RST1 for initializing the system, and a load signal LD indicating that data transfer of the first line has been completed. , A mode signal MODE1 representing a color mode, and a signal THWR representing that one byte of data has been prepared. The print enable signal EP is a simultaneous reading / thermal head interface unit 80, a parallel / serial conversion. The reset signal RST1 is supplied to the memory access unit 83 and the thermal head print control unit 85. The load signal LD and the mode signal MODE1 are supplied to the memory access unit 83 and the thermal head print control unit 85 (described later). A thermal head print controller 85, the signal THWR are applied respectively to the parallel / serial conversion memory access unit 83.

The simultaneous reading / thermal head interface section 80 is for realizing a direct recording mode in which the read image is directly recorded and output by the printer 14.
In this case, only a monochrome image is recorded due to the processing speed.

Therefore, the black recording data BVc output from the erasing circuit 67 is used as the recording data DT1 to be transferred to the thermal head 21, and the shift clock signal SFTCK internally generated by the serial / parallel converter 69 is used as the clock signal CK1. Is input and output as it is. When the transfer of the black recording data 8Vc for one line is completed, the latch signal LT1 is output. Also, since the thermal head 21 is driven in two parts, the thermal head 2
Strobe signal S for turning on the first four blocks of 1
TB1-4 (1) and strobe signals STB5-8 for turning on the last four blocks of thermal head 21
(1) is formed. The processing for one line is executed in synchronization with the line synchronization signal LNSVII. Further, strobe signals STB1 to STB4 are output from CPU 66.
(1) and pulse width data DP1 for setting pulse widths of the strobe signals STB5 to STB8 (1) are added.

The latch signal LD1 and the recording data D
T1, clock signals STB1-4 (1), STB5-8
(1) is added to one input side A of the selector 86.

The parallel / serial conversion / memory access section 83 alternately reads out the black recording data BVc and the red recording data RVc stored in the data memory 65 line by line and converts them into serial data. 21 and outputs the recording data DT2 to the thermal head 2.
The clock signal CK2 to be input to the counter 1 is formed and output. The operation of one line is started in synchronization with the one-line write end signal LDG output from the thermal head print control unit 85.

When reading data from the data memory 65, the parallel / serial conversion / memory access section 83 causes the DMA controller 71 to transfer data at high speed.

The thermal head print controller 85 outputs a latch signal LT2, strobe signals STB1 to STB4 (2) and a strobe signal STB5 to be output to the thermal head 21.
-8 (2). When the processing for one line is completed, a one-line write end signal LDG is generated, and this signal is output to the parallel / serial conversion / memory access unit 83.
Output to Further, pulse width data DP2 for setting pulse widths of the strobe signals STB1 to 4 (2) and STB5 to 8 (2) is added from the CPU 66. Note that the one-line write end signal LDG is also used inside the thermal head print control unit 85.

Then, the latch signal LT2 and the recording data D
T2, clock signal CK2, strobe signal STB1
4 (2) and STB5-8 (2) are added to the other input terminal B of the selector 86.

Since the operations of the parallel / serial conversion / memory access unit 83 and the thermal head print control unit 85 are synchronized by the one-line write end signal LDG, the latch signal LT2, the recording data DT2, the clock signal CK2, Strobe signals STB1 to STB4
(2) and STBs 5 to 8 (2) are output to the thermal head 21 at a predetermined timing.

The selector 86 selects the input terminal A when the selection signal SL output from the CPU 66 via the input / output circuit 84 is 1, and selects the input terminal B when the selection signal SL is 0. The signals applied to the input terminals A and B are output to the thermal head 21.

That is, when the input terminal A is selected, the latch signal LT1, the recording data DT1, the clock signal CK1, the strobe signals STB1 to 4 (1), STB
5 to 8 (1), when the input terminal B is selected,
Latch signal LT2, recording data DT2, clock signal C
K2, strobe signals STB1 to STB4 (2), STB5
8 (2) are output to the thermal head 21 as the latch signal LT, the recording data DT, the clock signal CK, and the strobe signals STB1 to STB4 and STB5 to STB8.

The heat storage data reading unit 87 counts the number of driven heating resistors for each predetermined number of blocks from the contents of the recording data DT applied to the thermal head 21, and interrupts each time the counting is completed. The signal INT is output to the CPU 66, and the CPU 66 takes in the count value. Thereby, the CPU 66 identifies the heating state (heat storage state) of the thermal head 21 and sets the pulse width of the next strobe signal to be given. A reset signal RST1 'internally inverted by the thermal head print controller 85 is applied to the heat storage data reader 87.

The thermal head 21 has a built-in thermistor (not shown), and the output signal SJ of the thermistor is converted into a digital signal by an analog / digital converter 88 and read by the CPU 66 at an arbitrary timing. As a result, the temperature information of the thermal head 21 is directly input to the CPU 66 and is referred to for setting the pulse width of the strobe signal.

With the above configuration, when the operator selects the black / red mode and sets the number of copies to 1, and turns on the start key 54, the CPU 66 moves the sheet 1 in the forward direction by the sheet motor 76. Along with
The image recorded on the sheet 1 is read by operating the line image sensors 9 and 10.

At this time, since the black / red mode is selected, the black / red mode is set in the color synthesizing / erasing circuit 64, and the serial / parallel converters 69 and 70 are set in that state.
Black recording data BVc and red recording data RVc
Is converted into a parallel signal, and is stored in a predetermined storage area of the data memory 65 by the DMA controller 71.

In this manner, when the reading of the image for one screen is completed and stored in the data memory 65,
The CPU 66 then causes the printer 14 to record and output the stored image.

That is, the CPU 66 first causes the selector 86 to select the input terminal B, and sets the mode data MO
With the black / red mode set in DE1, the operations of the parallel / serial conversion / memory access unit 83 and the thermal head print control unit 85 are started, and at the same time, the motor 27 of the printer 14 is rotated in the counterclockwise direction A. Let it.

Thus, the black recording data BVc and the red recording data BVc stored in the data memory 65 are converted into a parallel / serial conversion / memory access unit 83 for each line.
The recording data DT2 and the clock signal CK2 are formed alternately, and are output to the thermal head 21 via the selector 86 as the recording data DT and the clock signal CK.

As a result, the recording data DT is stored in the shift register SRG (see FIG. 27) of the thermal head 21.

At the timing immediately after the recording data DT for one line is output, the latch signal LT2 is output from the thermal head print control unit 85 and the selector 8 outputs the latch signal LT2.
6, the signal is applied to the thermal head 21 as a latch signal LT, whereby the data of the shift register SRG of the thermal head 21 is stored in the latch circuit LCT (see FIG. 27).

The strobe signal S having a pulse width corresponding to the pulse width data DP2 output from the CPU 66.
TB1 to 4 (2) and STB5 to 8 (2) are sequentially output, and these strobe signals STB1 to 4 (2), STB
B5 to 8 (2) are transferred to the thermal head 2 as strobe signals STB1 to STB4 and STB5 to STB8 via the selector 86.
In addition, the thermal head 21 operates to record an image for one line.

At the same time, the multicolor thermosensitive recording paper 20 is conveyed at a predetermined speed by the motor 27, so that the image read at this time is recorded on the multicolor thermosensitive recording paper 20 in three colors of black and white and red. Is done.

The CPU 66 is provided with a heat storage data reading unit 87.
When an interrupt signal INT is applied from the controller, the heat storage data reading unit 8
7, the pulse width data DP2 is set based on the input data and the temperature information output from the analog / digital converter 88. When the pulse width data DP2 is set, it is determined whether the data to be recorded at that time is the black recording data BVc or the red recording data RVc. With the pulse width b as the center, and in the case of red recording data RVc, the pulse width (c−
The pulse width is set based on each data described above, centering on b).

The pulse width data DP2 is switched immediately before the output of the strobe signals STB1 to STB4 or the strobe signals STB5 to STB8, and the thermal head print control unit 85 is switched.
Output to

When such a process is executed until an image for one page is recorded, the CPU 66 rotates the motor 27 in the clockwise direction B, and cuts the multicolor heat-sensitive recording paper 20 by the cutter 23, whereby One copy of the contents of the board written on the screen is formed and output.

If two or more copies have been set by the operator at this time, the above-described processing is repeatedly executed for the set number of copies to form and output the set number of copies.

Next, when the operator selects the long mode, when the start key 54 is turned on, the CPU 66 starts reading an image in the same manner as described above, and at this time, the selector 86 selects the input terminal A. Let it.

Then, the motor 27 is driven in the counterclockwise direction A in order to start reading and start recording by the printer 14 at the same time.

Accordingly, in this case, the recording data DT1 and the clock signal CK1 output from the simultaneous reading / thermal head interface unit 80 are output to the thermal head 21 as the recording data DT and the clock signal CK via the selector 86, and When the recording data DT for one line is input to the shift register SRG to the thermal head 21, a latch signal LT 1 is output from the simultaneous reading / thermal head interface section 80, and the latch signal LT 1 is output via the selector 86 as the latch signal LT. 21 so that the recording data D for one line input to the shift register SRG
T is stored in the latch circuit LCT.

Next, the strobe signals STB1 to STB4 are output from the simultaneous reading / thermal head interface unit 80.
(1), STB5-8 (1) are sequentially output, and these are output via a selector 86 to strobe signals STB1-4, STB4
B5 to B8 are output to the thermal head 21, and as a result, the thermal head 21 is driven and a monochrome image of one line is recorded on the multicolor thermal recording paper 20.

In this case, the CPU 66 sets only the pulse width at the time of recording the black recording data BVc as the pulse width data DP1 in the same manner as described above.

In this case, since the mode is the long mode, the above processing is executed until all the screen images of four pages are read and recorded, or until the clear / stop key 53 is turned on.

When the recording of the image is completed, the multicolor heat-sensitive recording paper 20 is cut in the same manner as described above. As described above, in this embodiment, when the long mode is selected, the image is recorded as a black and white image, so that “all black” and “red erase” can be set as copy colors. In this case, since the read image is not stored in the data memory 65, the number of copies is always one.

Note that the CPU 66 sets the strobe signal ST
The pulse width is set for each of B1 to B8, whereby the drive time of each block of the thermal head 21 is controlled by the contents of the print data immediately before.

In this manner, the set number of copies of the board contents can be formed in the mode set by the operator.

When the date copy mode is selected, the CPU 66 stores the date display data previously formed in the predetermined area of the data memory 65 at the time when the recording of the image of one page is completed. Is transferred to the writing system as the recording data, thereby incorporating the date at the end of the recording image.

Further, when “all black” or “red erase” is selected as the copy color and the image is recorded and output as a black and white image, the CPU 66 operates the simultaneous reading / thermal head interface unit 80 when reading the image. At the same time, the image data read by the serial / parallel converters 69 and 70 and the DMA controller 71 are stored in the data memory 65.

When the reading is completed, the parallel / serial conversion / memory access unit 83 and the thermal head print control unit 85 are operated for the remaining number of the set number of copies, and the images stored in the data memory 65 are stored. The data is read and an image is recorded.

As a result, when recording and outputting a monochrome image, the first copy is output immediately after the start key 54 is turned on, so that the recording waiting time until the first copy is output is reduced. I do.

FIG. 8 shows an example of the sensor drive / image signal processing section 61. The sensor driving / image signal processing unit 6
2 is the same as the sensor drive / image signal processing unit 61.

In the figure, the image signal RA (analog signal) output from the line image sensor 9 is inverted by an inverting amplifier 101, and
2, the impedance of the capacitor 103 is changed.
After the DC component is removed, the reference level is set by the DC regeneration amplifier 104, and is applied to the peak hold circuit 106 and the analog / digital converter 107 via the variable gain amplifier 105.

The peak hold circuit 106 detects the peak value of each line and applies the detected value to the reference level input terminal of the analog / digital converter 107, whereby the background level of the image is changed for each line. Is converted to a digital image signal RD having a predetermined number of bits and output.

The output signal of the analog / digital converter 107 is output to the color recognition circuit 63 and the multiplexer 108 and the tristate buffer circuit 109
Via the white waveform memory 110.

Thus, at the start of image reading, the digital image signal RD obtained when a reference white image is read
Are stored in the white waveform memory 110 as reference white waveform data. When the image on the sheet 1 is actually read, the data stored in the white waveform memory 110 is stored in the latch circuit 111.
Variable gain amplifier 105
, Whereby shading correction of the read image is performed.

The line synchronizing signal LNSYN output from the pulse generator 79 is applied to the main scanning counter 112, and the clock signal ELCK is supplied to the main scanning counter 112.
The clock signal ELCK2 is applied to the timing decoder 113 and the gate circuit 114, and is applied to the gate circuit 114.

The main scanning counter 112 has the white waveform memory 11
Address data for accessing 0 is generated, and the operation timing of the timing decoder 113 is set. Thus, the reference white waveform data is read out from the white waveform memory 110 bit by bit, and the read image is subjected to shading correction bit by bit.

The timing decoder 113 generates a pulse signal PTG and a transfer clock signal PS1 for setting the start of image reading of the line image sensor 9, and generates a pulse signal PT6, a transfer clock signal PS1, and a transfer clock. A signal obtained by inverting signal PS1 by inverter 115 is applied to level conversion circuit 116.

From the gate circuit 114, a reset signal PR1 for resetting the output of the line image sensor 9 for each bit is applied to the level conversion circuit 116.

The level conversion circuit 116 converts each input signal to an input level of the line image sensor 9 and outputs this to the line image sensor 9, whereby the line image sensor 9 is driven. You.

FIG. 9 shows an example of the color recognition circuit 63.

In the figure, the digital image signal RD is applied to the input terminal A of the full adder 121 and the full subtractor 112, and the digital image signal BD is applied to the input terminal B of the full adder 121 and the full subtractor 112. Have been added.

The full adder 121 forms the result of the full addition of the digital image signal RD and the digital image signal 8D. The output data is applied to the input terminal A of the comparator 123. Is to completely subtract the digital image signal BD from the digital image signal RD, and the output data is applied to the input terminal A of the comparator 124.

The reference value input terminal B of the comparator 123 is supplied with lightness data DDL for identifying black and white (lightness) of an image from the lightness data setting unit 125, and the data of the input terminal A is input to the input terminal B. Output signal SDL rises to 1 when the data is larger than the data of the AND circuit 127 and the AND circuit 12 via the inverter 126.
8 is applied to one input terminal.

The saturation data DDM for identifying the saturation (red) of the image is added to the reference value input terminal 8 of the comparator 124 from the saturation data setting unit 129. When the data is larger than the data at the input terminal B, the output signal SDM rises to 1, and the signal SDM is applied to the other input terminal of the AND circuit 127 and the inverter 1
The signal is applied to the other input terminal of the AND circuit 128 via 30.

As a result, the black signal SB is output from the AND circuit 127, and the red signal SR is output from the AND circuit 128.
Is output.

Note that the brightness data setting unit 125 has a CPU
66, a circuit that can change the set value, for example, a latch circuit or the like. In this way, when the mode for increasing the copy density is selected, the value of the lightness data DDL can be increased, whereby the copy density can be increased. Also,
The brightness data DDL and the saturation data DDM are directly
It can also be set from U66.

FIG. 10 shows an example of the color combining / erasing circuit 64.

In the figure, the red signal SR is supplied to the selector 13
5 are applied to one input terminal of the OR circuit 136 in addition to the input terminals 1D, 2A and 2D. The black signal SB is applied to the input terminal 1C of the selector 135 and to the other input terminal of the OR circuit 136.

The output signal SBR of the OR circuit 136 is applied to the input terminals 1A and 18 of the selector 135.
The input terminals 28 and 2C of the selector 135 are connected to the ground level, and therefore, 0 is input to the input terminals 2B and 2C.

The selector 135 has control input terminals MA and MB.
(1A, 2A), (1B, 2B), (1C, 2) depending on the values of mode signals MD0 and MD1 applied to
C), (1D, 2D) input terminals are selected, and input terminals 1A,
1B, 1C, 1D and input terminals 2A, 2B, 2C, 2D
Are connected to the output terminal 1Y and the output terminal 2Y, respectively.

As a result, the contents of the black recording data BV and the red recording data RV output from the output terminals 1Y and 2Y according to the values of the mode signals MD0 and MD1 are as shown in Table 1 below.

[0157]

[Table 1]

In this manner, black / red, all black, red eraser,
Print data in each of the black-out color modes is formed.
Note that print data in other color modes can also be formed.

Next, the erasing circuits 67 and 68 will be described.

For example, as shown in FIG.
Is full width LL1, only the image of the width of the central portion LL2 is recorded on the multi-color thermal recording paper 20, and the images of the lengths LL3 and LL4 at both ends are masked by first using the recording data. The data of the number of pixels NB3 corresponding to the part of the length LL3 and the data of the number of pixels N84 corresponding to the part of the last length LL4 may be converted into white images.

FIG. 12 shows an example of the rimming circuit 67.
The configuration of the rimming circuit 68 is the same as that of the rimming circuit 6.
Same as 7.

In the figure, a clock signal ELCK (see FIG. 13B) is applied to clock input terminals of counters 141 and 142, and a data valid signal DTEN (FIG. 13).
(See (b)) is applied to the enable inputs of the counters 141 and 142, whereby the data valid signal DTE
The counters 141 and 142 start from the timing when N is added.
Is started.

The counter 141 has a data setter 143
, Data DN1 corresponding to the number of pixels NB3, and data DN2 corresponding to the number of pixels obtained by subtracting the number of pixels BN4 from the number of pixels for one line from the data setter 144 are added to the counter 142.

As a result, the counter 141 raises the output signal SDN1 (see FIG. 13C) to the logical level H immediately after the start of counting, and when the count value becomes a value corresponding to the data DN1, the signal 141 falls. . The counter 142 outputs the output signal SDN2 (FIG. 13) immediately after the start of counting.
(See (d)) to a logic level H, and when the count value reaches a value corresponding to the data DNI, the signal SDNI falls.

This signal SDNI is applied to one input terminal of an AND circuit 146 via an inverter 145.
Signal SDN2 is applied to the pond input of AND circuit 146. The output signal of the AND circuit 146 (see FIG. 13E) is supplied to one input of an AND circuit 147 and an AND circuit 148 that respectively gate the black recording data BV and the red recording data RV (see FIG. 13F). The black recording data BVc and the red recording data RVc from which the data at both ends of one line have been removed are formed, thereby forming a serial / parallel converter 69 and a simultaneous reading / thermal head interface unit. 80 and to the serial / parallel converter 70.

FIG. 14 shows the serial / parallel converter 6
9 and 70 are shown as examples. In this example, it is assumed that the serial / parallel converters 69 and 70 are integrally formed, and that the width of the data bus in the system bus 74 is 8 bits.

In the figure, black recording data BVc and red recording data RVc are input to 8-bit shift registers 151 and 152, respectively.

The clock signal ELCK (FIG. 15)
(A) and a data valid signal DTEN (see FIG. 15).
(See (b)) are respectively applied to two input terminals of an AND circuit 153, and the output of the AND circuit 152 is
As shift clock signal SFTCK (see FIG. 15C), shift registers 151 and 152 and counter 1
54 and output to the simultaneous reading / thermal head interface unit 80.

As a result, shift registers 151 and 15
In the state where the black recording data BVc and the red recording data RVc are transferred to each other by 8 bits, the output QD of the counter 154 rises, whereby the flip-flop 155 is set, and the output signal of the flip-flop 155 becomes the data request signal. DRQ0 (see FIG. 15 (f))
Is output to the DMA controller 71 as
At the rising edge of the signal, the data of the shift registers 151 and 152 are latched by the latch circuits 156 and 157, and the flip-flop 158 is set, and the output is set to the data request signal DRQ1 (see FIG. 15 (h)).
Output to MA controller 71.

Thus, first, data request signal DR
After QO is activated, flip-flop 158
Since the data request signal DRQ1 rises after a delay of the operation time, the DMA controller 71 first raises the data acceptance signal DACK0 (see FIG. 15 (g)) in response to the data request signal DRQO having a higher priority. At the same time, after receiving the address of the transfer destination of the 8-bit black recording data BVc in the data memory 65 from the CPU 66 and setting it, the data read signal R
D (see FIG. 15 (j)) is output for a predetermined time.

As a result, the data read signal RD is applied to the output control input terminal of the latch circuit 156 via the AND circuit 159 which has been enabled by the data reception signal DACKO (see FIG. 15 (k)). As a result, 8-bit black recording data BVc is stored in a predetermined area of the data memory 65 (see FIG. 15 (m)).

Next, DMA controller 71 responds to data request signal DRQ1 by receiving data acceptance signal DACK1.
(See FIG. 15 (i)) and the CPU 6
6, the address of the transfer destination of the 8-bit red recording data RVc at that time is received, and after setting it, the data read signal RD is output for a predetermined time.

As a result, the data read signal RD is applied to the output control input terminal of the latch circuit 157 via the AND circuit 160 enabled by the data reception signal DACK1 (see FIG. 15 (l)). , 8 bits of red recording data RVc are stored in the data memory 6.
5 in a predetermined area.

Further, data acceptance signals DACK0, DACK
K1 allows flip-flops 155, 15 respectively.
8 is cleared, and the counter 154 is cleared by the signal obtained by delaying the output of the flip-flop 155 by the delay circuit 161, thereby starting the operation in the next cycle.

FIG. 16 shows an example of the simultaneous reading / thermal head interface section 80.

In the figure, the logical level H at the start of recording
Enable signal EP (see FIG. 17)
17A is applied to the data input terminal of the flip-flop 171 and is generated at the timing when the processing of one line is started.
) Is applied to the clock input terminal of the flip-flop 171 via the inverter 172, and the output of the flip-flop 171 and the output of the inverter 172 are applied to two input terminals of the AND circuit 173.

Therefore, the second and subsequent line synchronization signals LNSYN from the start of recording are output from the AND circuit 173 (see FIG. 17C), and the mono-multi circuit 174 is output at the falling edge of the output signal of the AND circuit 173. Operates, the output signal of the mono-multi circuit 174 is output as a latch signal LT1 of negative logic (see FIG. 17D), and at the rising edge of the latch signal LT1, one cycle of the line synchronization signal LNSYN is output. A counter / timer circuit 175 in which a time slightly shorter than / 2 is set, and four circuits in which the pulse widths of the strobe signals STB1 to 4 (1) (see FIG. 17 (f)) are respectively set. The counter / timer circuit 176 starts operating.

As a result, first, strobe signals STB1 to STB4 (1) are output from counter / timer circuit 176.

Next, when the output of the counter / timer circuit 175 falls (see FIG. 17 (e)), the pulse widths of the strobe signals STB5-8 (1) (see FIG. 17 (g)) are set respectively. Counter consisting of four circuits /
The timer circuit 177 starts operating.

Thus, strobe signals STB1 to STB4
Subsequent to (1), strobe signals 5 to 8 (1) are output.

The shift clock signal SFTCK and the black recording data BVc correspond to the clock signal CK1 respectively.
(See FIG. 17H) and the recording data DT1 (FIG.
(See (i)).

The strobe signals STB1 to STB4
(1), pulse width data DP1 for setting pulse widths of STBs 5 to 8 (1) are set in counter / timer circuits 175 and 177 at appropriate timing.

FIG. 18 shows an example of the parallel / serial conversion / memory access unit 83.

In FIG. 19, when a reset signal RST1 (see FIG. 19C) for initializing the system is output, the counter 181 is cleared by the output of the OR circuit 180, and the output of the NOR circuit 182 is output. As a result, the flip-flops 183 and 184 are cleared (FIG. 19)
(H) and (i)) together with the flip-flop 185
Is preset to a set state (see FIG. 19G),
Further, a counter 187 is output by the output of the OR circuit 186.
Is cleared, and the output of the OR circuit 186 is
8 to the flip-flop 189 to clear the flip-flop 189 (see FIG. 19 (f)), whereby the parallel / serial conversion / memory access unit 83 is initialized.

Next, a print enable signal EP (FIG. 1)
9 (d)), the flip-flop 18
3 attains a logic level H, and at this time, a one-line write end signal LDG of negative logic (FIG. 1)
9 (e) is at the logic level H, the output of the AND circuit 190 rises, whereby the flip-flop 189 is set, and the output of the flip-flop 189 becomes the output of the flip-flop 185. The data request signal DRQ is output to the DMA controller 71 via the AND circuit 191 applied to the input terminal (see FIG. 19 (j)). The data request signal DRQ is counted by the counter 187.

As a result, the DMA controller 71
The PU 66 is notified that data has been requested, whereby the CPU 66 determines the data to be output at that time and notifies the DMA controller 71 of the address.

Then, the DMA controller 71 raises the data acceptance signal DACK, reads the data of the address notified at that time from the data memory 65, outputs the signal THRW, and sends the data to the shift register 192. Latch.

The data accept signal DACK is inverted by the signal DACK ′ by the inverter 193 (FIG. 19).
(K), and the flip-flop 185 is cleared at the falling edge of the signal DACK ', whereby the data request signal DRQ falls and the signal DACK' falls.
The flip-flop 183 is set at the rising edge of ACK '.

On the other hand, clock signal CLK2 (FIG. 19)
(See FIG. 19A) is applied to the negative input terminal of the AND circuit 194 and the clock input terminal of the flip-flop 195, and the clock signal 2ELCK (see FIG.
One input terminal of the AND circuit 196 to which the output of the flip-flop 184 is added to the other input terminal and the inverter 1
97 is applied to the other input terminal of the AND circuit 194.

The output of the AND circuit 194 is applied to one input terminal of the AND circuit 198 to which the output of the flip-flop 183 is added to another input terminal. Therefore, after the flip-flop 183 is set, Is
The output of the AND circuit 194 is output via the AND circuit 198.
The signal is applied to the clock input terminal of the flip-flop 184 (see FIG. 19 (l)), whereby the flip-flop 184 is set.

When flip-flop 184 is set in this manner, AND circuit 196 becomes operable. Therefore, thereafter, clock signal 2ELCK is supplied to shift circuit signal PSCLK via AND circuit 196 (FIG. 19 (m)). (See Reference) is applied to the clock input terminals of the counter 181, the flip-flop 195 and the shift register 192.

As a result, the flip-flop 195 outputs the clock signal CLK2 as shown in FIG.
Is output from the shift register 192, as shown in FIG.
The recording data DT2 as shown in FIG. 9 (p) is output.

When one 8-bit data is output from the shift register 192 and the output terminal QD of the counter 181 rises (see FIG. 18 (n)), this signal is output to the flip-flop via the NOR circuit 182. Step 18
Clear 3,184 and flip-flop 18
5, the parallel / serial conversion / memory access unit 83 sets the reset signal RST1
Is returned to the state at the time when the print enable signal EP is output.

Thereafter, this operation is repeated, whereby the data of 8 bits is converted into the serial recording data DT2.
, And the count value of the counter 187 increases (see FIGS. 20A to 20I).

When the processing for one line is completed, the count value of the counter 187 becomes a predetermined value (for example, 216 in this case because the data for one line is composed of 1728 bits under the above-described conditions). , The output of the gate circuit 199 of the counter 187 rises, and the one-shot circuit 200 is triggered by the rising timing of the output to output the one-line end signal EOL.

As a result, the flip-flop 189 is cleared, the data request signal DRQ is not generated, and the flip-flops 183 and 184 are kept cleared when the output of the 8-bit data at that time is completed. Therefore, the shift clock signal PSCLK
Will not be output.

Thereafter, the one-line write end signal LD
When G is output, the flip-flop 189 is set, whereby the parallel / serial conversion / data access unit 83 repeatedly executes the processing for one line as described above. This processing is performed by the print enable signal E
It is repeatedly executed until P falls.

FIG. 21 shows a thermal head print controller 85.
An example is shown.

Referring to FIG. 22, first, a reset signal RST1 (FIG. 22) output to initialize the system is provided.
(Refer to (a)), the flip-flop 212 is cleared after being inverted by the inverter 211, and is output to the thermal storage data reading unit 87 as the reset signal RST1.

On the other hand, if the color mode of “black / red” or “black erase” is selected at this time, the mode signal MODE1 is at the logic level H, and the inverted output of the flip-flop 212 is turned on. 22, the output of the AND circuit 213 whose mode signal MODE1 is applied to another input terminal, that is, the selection signal SLCT (FIG. 22).
(See (g)) rises to the logic level H.

The selection signal SLCT is supplied to the AND circuit 21.
4 is connected to one input terminal and the inverter 215
Is applied to one input terminal of the AND circuit 216.

The print enable signal EP (FIG. 22)
(B) is output, and when the load signal LD (see FIG. 22 (c)) is output from the CPU 66 when the data transfer for one line by the parallel / serial conversion / memory access unit 83 is completed. This load signal LD
Triggers the one-shot circuit 218 via the OR circuit 217, whereby the one-shot circuit 218 outputs a negative logic latch signal LT2 (see FIG. 22 (e)), whereby the shift register of the thermal head 21 is shifted. The recording data transferred to the SRG is stored in the latch circuit LCT. Further, the output of the OR circuit 217 triggers the flip-flop 212 to invert its output,
The selection signal SLCT falls.

Further, the one-shot circuit 219 is triggered at the rising edge of the latch signal LT2, whereby a one-line write end signal LDG of negative logic (see FIG. 22 (f)) is output, and the one-line write end is output. The flip-flop 220 is set at the rising edge of the signal LDG, thereby enabling the AND circuits 214 and 216 to operate.

At this time, since the output of AND circuit 216 attains logical level H, counter / timer circuit 2
21 gate A and gates 1-4 are selected, whereby the counter / timer circuit 221 first outputs 1
A negative logic synchronizing signal BLSYN which falls for the same time when 1/2 of the maximum time required for black recording of the line has elapsed.
(See FIG. 22 (k)) and strobe signals STB1 to STB4 (2) of negative logic (see FIG. 22 (n)).

When the synchronizing signal BLSYN falls, the output of the AND circuit 222 falls, whereby the output of the AND circuit 222 is inverted via the inverter 223 and applied to the gates 5 to 8 of the counter / timer circuit 221. The synchronizing signal THSYN (see FIG. 22 (m)) rises, so that the counter / timer circuit 221 outputs negative logic strobe signals STB5 to STB8.
(2) (see FIG. 22 (o)) is output.

When the synchronizing signal BLSYN rises, the flip-flop 224 is set, whereby the signal LTRQ (see FIG. 22D) rises.

The signal LTRQ is applied to the other input terminal of the OR circuit 217, whereby the load signal L
As in the case where D is applied, latch signal LT2 and one-line write end signal LDG are output. When the one-line write end signal LDG is output, the flip-flop 224 is cleared, so that the signal LTRQ falls at that time.

When the signal LTRQ first occurs, the flip-flop 212 is triggered and inverted.
Thereby, the logic state of the selection signal SLCT is switched to select the gate B of the counter / timer circuit 221. In this case, instead of the synchronization signal BLSYN,
A negative logic synchronizing signal RDSY that falls for the same time when half of the maximum time required for red recording of one line has elapsed.
N (see FIG. 22 (l)) is output.

Thereafter, the above operation is repeated every time the signal LTRQ is generated until the print enable signal EP falls, whereby the operation for black recording and the operation for red recording are performed. Executed alternately.

The strobe signals STB1 to STB4
(2), pulse width data DP2 for setting pulse widths of STBs 5 to 8 (2) are set in the counter / timer circuit 221 at appropriate timing.

When the color mode of "all black" or "red erase" is selected and the mode signal MODE1 is at the logic level L, the gate A is always selected, so that only the operation during black recording is performed. It is executed repeatedly.

Thus, latch signal LT2 and strobe signals STB1-4 (2), STB5-8
(2) is generated, and the one-line write end signal L
DG is output.

Here, FIGS. 23A to 23H and FIGS. 24A to 24H show the output status of each signal at the time of data recording. Note that the ones shown in FIGS.
When the “black / red” color mode is selected,
When the “black erase” color mode is selected, the same timing is obtained and the recording data DT2
Are all "red". Also, FIGS.
(H) shows the case where the “red erase” color mode is selected. When the “all black” color mode is selected, the same timing is obtained, and the recording data is recorded. The content of DT2 becomes "black and red".

FIG. 25 shows an example of the heat storage data reading section 87.

In the figure, the recording data DT is applied to one input terminal of an AND circuit 231, and the clock signal CK is applied to the pond input terminal of the AND circuit 231 and the clock input terminal of the counter 232.

Therefore, the clock signal CK when the content of the recording data DT is 1 is output from the AND circuit 231, and this is counted by the counter 233.

When the count value of the counter 232 reaches a predetermined value, in this case, the number of heating resistors in each block of the thermal head 21, that is, 216, the output of the gate circuit 234 rises, whereby the count value of the counter 233 is latched. It is stored in the circuit 235.

The output of the gate circuit 234 is applied via a delay circuit 236 to the other input terminal of the AND circuit 237 having one input terminal to which the print enable signal EP is applied. Is output to the CPU 66 as an interrupt signal INT. by this,
The CPU 66 reads the data stored in the latch circuit 235.

Further, the latch signal LT and the reset signal RS
A signal obtained by inverting the output of T1 and the delay circuit 236 by the inverter 238 is applied to the NOR circuit 239. The output of the NOR circuit 239 resets the counters 232 and 233.

When the heat storage data for one block is counted in this manner, an interrupt signal INT is generated, and the heat storage data is taken into the CPU 66.

In the above-described embodiment, the data of the logical sum of the black image and the blush image is recorded first, and then the data of the blush image are recorded. However, the order can be reversed. . Further, as the color mode, a color mode other than those described above, for example, color inversion or the like can be provided.

Incidentally, the composition of each layer of the multicolor thermal recording paper 21 described above is, for example, the one disclosed in JP-A-606891 / 1985 and that disclosed in JP-A-105586 / 1985. is there.

In the former, the red coloring layer contains a leuco dye and a phenolic compound, and the black erasing layer has the general formula (A)
The black coloring layer contains a leuco dye and a thiourea derivative represented by the general formula (B).
(Refer to the gazette for the general formulas (A) and (B).)

In the latter, the red coloring layer contains a leuco dye and a phenolic compound, and the black erasing layer contains at least one decoloring agent selected from a morpholine compound and an aliphatic amine. The color-forming layer contains a leuco dye and a thiourea derivative represented by the general formula (A), and contains a heat-fusible substance and a water-soluble polymer binder between the black color-forming layer and the black erasing layer as main components. Layers are provided. (Note that
See the gazette for formula (A). )

[0225]

As described above, according to the present invention,
The contents described in the first color and the second color in the same writing screen area are optically identified and read, respectively, and the calorie at discrete levels corresponding to the first color and the second color is calculated. By printing in pixel units, the content of the writing screen content is formed by sequentially laminating an A-color coloring layer corresponding to the first color, a decoloring layer, and a B-color coloring layer corresponding to the second color on a base layer. Means for synthesizing the description of the first color corresponding to the high-level heat quantity with the description content of the second color corresponding to the low-level heat quantity in an electronic blackboard apparatus for recording on multicolor recording thermosensitive recording paper. Storage means for storing the combined content combined by the combining means and the description content described in the first color, and the content described in each of the first color and the second color. In the above-mentioned A color and B color, respectively. When reading the combined contents and the description contents described in the first color from the storage means, applying a low level of heat to the combined contents to develop the color in the B color By applying a heat quantity corresponding to a difference between the high-level heat quantity and the low-level heat quantity to the content described in the first color,
After erasing the recorded content that is colored in color, the color is developed in color A, so that the first color pixels that require a high level of heat can be recorded more quickly.
An effect that an image composed of the pixels of the first color and the second color can be recorded in a short time can be obtained.

[Brief description of the drawings]

FIG. 1 is a graph for explaining the principle of the present invention.

FIG. 2 is a waveform diagram showing a driving example of a multicolor thermal recording apparatus according to the principle of the present invention.

FIG. 3 is a schematic diagram showing a configuration example of an electronic blackboard device according to one embodiment of the present invention.

FIG. 4 is a graph showing an example of spectral characteristics of a red filter and a cyan filter.

FIG. 5 is a schematic configuration diagram illustrating an example of a printer.

FIG. 6 is a plan view showing an example of an operation display unit.

FIG. 7 is a block diagram showing an example of a control system.

FIG. 8 is a block diagram illustrating an example of a sensor driving / image signal processing unit.

FIG. 9 is a block diagram illustrating an example of a color recognition circuit.

FIG. 10 is a block diagram illustrating an example of a color combining / erasing circuit.

FIG. 11 is a schematic diagram for explaining the principle of a border erase circuit.

FIG. 12 is a block diagram illustrating an example of a border erase circuit.

FIG. 13 is a waveform chart for explaining the operation of the rimming circuit.

FIG. 14 is a block diagram illustrating an example of a serial / parallel conversion unit.

FIG. 15 is a waveform chart for explaining the operation of the serial / parallel converter.

FIG. 16 is a block diagram showing an example of a simultaneous reading / thermal head interface unit.

FIG. 17 is a waveform chart for explaining the operation of the simultaneous reading / thermal head interface unit.

FIG. 18 is a block diagram showing an example of a parallel / serial conversion / memory access unit.

FIG. 19 is a waveform chart for explaining an example of the operation of the parallel / serial conversion / memory access unit.

FIG. 20 is a waveform chart for explaining an example of the operation of the parallel / serial conversion / memory access unit.

FIG. 21 is a block diagram showing an example of a thermal head print control unit.

FIG. 22 is a waveform chart for explaining the operation of the thermal head print control unit.

FIG. 23 is a waveform chart for explaining the operation of the thermal head print control unit.

FIG. 24 is a waveform chart for explaining the operation of the thermal head print control unit.

FIG. 25 is a block diagram showing an example of a heat storage data reading unit.

FIG. 26 is a schematic cross-sectional view showing an example of a multicolor thermal recording paper.

FIG. 27 is an operation principle diagram of the multicolor thermal recording apparatus.

FIG. 28 is a circuit diagram showing an example of a thermal head.

FIG. 29 is a waveform diagram showing a driving example of a conventional device.

[Explanation of symbols]

 9, 10 Line image sensor 21 Thermal head 61, 62 Sensor drive / surface signal processing unit 63 Color recognition circuit 64 Color synthesis / erase circuit 65 Data memory 66 CPU (Central processing unit) 67, 68 Border erasure circuit 69, 70 Serial / Parallel conversion unit 71 DMA (direct memory access) controller 72 Program memory 73 Work memory 80 Simultaneous reading / thermal head interface unit 83 Parallel / serial conversion / memory access unit 85 Thermal head print control unit 86 Selector 87 Thermal storage data reading unit 88 Analog / Digital converter

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification number Agency reference number FI Technical display location H04N 1/028 B41J 3/00 B 1/032 3/20 115C

Claims (1)

[Claims] 1. A method according to claim 1, wherein the contents written in the first color and the second color are optically identified and read in the same writing screen area, and discrete contents corresponding to the first color and the second color are read. By printing the calorific value of each level on a pixel-by-pixel basis, the contents of the writing screen content can be displayed on the base layer in the A color forming layer corresponding to the first color, the decoloring layer, and the B color forming layer corresponding to the second color. In a multi-color recording thermosensitive recording paper, which is formed by sequentially laminating the first color corresponding to a lower level of heat and the first color corresponding to a higher level of heat. A synthesizing unit for synthesizing; and a storage unit for storing the synthesizing content synthesized by the synthesizing unit and the description content described in the first color. Write the contents described above in A color And when recording in B color,
The combined content and the description content described in the first color are read out from the storage means, and a low-level heat is applied to the combined content to develop the B color, and then the first color After applying the heat amount corresponding to the difference between the high-level heat amount and the low-level heat amount to the description content described in the above, the recorded content colored in the B color is erased, and then the A content is erased. An electronic blackboard device characterized by being colored in a color.