JPS6348059A - Color picture processor - Google Patents

Abstract

PURPOSE:To improve the picture quality of a color picture by selecting the start time of a writing-in on an image forming body based on a drum index signal obtained being synchronized with the revolution of the image forming body. CONSTITUTION:A color picture information is read through the CCD, etc., of a picture reader 10, and is converted to a color picture signal, thereafter, is separated into plural chrominance signals, e.g., three kinds of color of red, blue and black by a chrominance signal generating means 20, and an electrostatic latent image is formed by the separated chrominance signals. The electrostatic latent image, that is the writing-in time of the color signal, is regulated based on the index signal obtained from the drum. Because the writing-in time is controlled at every time of the writing-in of the chrominance signal, a registration is not deteriorated even when the picture is registration-recorded, and it does not change even when a load for the drum fluctuates. Thus, the color picture record with a good registration and with a improved picture quality can be obtained. 30: binarization circuit, 40: interface, 99: system bus, 100: output device, 200: first control part (for main body control), 250: second control device (for optical and driving control), 301: color picture data, 302: chrominance signal, 303: binary data, 304: modulation signal, 305: serial information data, 306: scanning start signal.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is applicable to a simple electrophotographic color copying machine that records a desired color image through a plurality of exposure processes. The present invention relates to a suitable color image processing device.

[Background of the Invention] In order to record a color original in a color image processing device using an electronic copying machine, the color original is first separated into a plurality of color separation images, and each of the partially resolved color signals is Then, the color separated image is converted into an electrostatic latent image on the image forming body, and
When the development process corresponding to all colors is completed, a transfer/fixing process is performed to record (copy) a color image corresponding to the color original.

Therefore, in a color image processing apparatus that performs such color recording processing, in order to perform color recording, it is necessary to rotate the image forming member a plurality of times for at least a plurality of color numbers. In this case, mutual alignment is required between the previously developed latent image and the next developed latent image.

In other words, if the writing start position of the previously developed latent image differs from the writing start position of the next developed latent image, color misregistration will occur and the image quality of the recorded color image will deteriorate significantly. be.

For this reason, registration adjustment regarding recorded colors is very important.

The deterioration of registration is caused by the fact that the position of the leading edge of the document in the optical system and the initial rotational position of the drum are shifted each time an image signal is written. Therefore, in order to adjust the registration, it is sufficient to control the relationship between the writing timing and the drum rotational position so that they always have a predetermined relationship.

In order to adjust the registration, the following methods can be considered.

A color image processing apparatus is equipped with a drum drive circuit that is controlled by a PLL in order to drive a rotating drum that is an image forming body. A drum control command signal sent from a control section consisting of the following is supplied to an encoder in the drive circuit, and a drum drive motor (main motor) is controlled based on the output of this encoder.

Therefore, the clock signal of the encoder is used as an encoder for sequence control which is also used for registration control, and based on this clock signal, the drum
The above problem can be solved by counting the number of pulses per cycle and aligning the edges of the image based on this number of pulses ◇ [Problem to be solved by the invention] By the way, the encoder clock When determining one revolution of the drum using a signal, there is no particular problem if one revolution of the drum and the number of pulses of the encoder have an integer relationship.

However, since the clock frequency of the encoder is set to drive the main motor, there is often no integer relationship between one revolution of the drum and the number of pulses of the encoder.

If the encoder clock signal is used as a drum rotation detection signal in such a state where there is no integer relationship, one revolution of the drum cannot be counted with an integer number of encoder pulses. Therefore, if images are superimposed while rotating the drum several times as described above, errors in non-integer parts will accumulate, and the initial position of one revolution of the drum will gradually shift, resulting in the position of the leading edge of the image. becomes misaligned. That is, the registration deteriorates as the rotation of color recording increases.

Further, even if the main motor rotates at a constant speed, the load on the drum fluctuates greatly due to repeated press-on and release of the cleaning blade and cleaning roller. As a result of such load fluctuations, the rotational speed of the drum changes slightly.

It is clear that such load fluctuations also degrade registration.

Therefore, the present invention solves these problems and proposes a color image processing device that has good registration and, therefore, can improve the image quality of color images.

[Means for solving the problem 1 In order to solve the above-mentioned problem, in this invention,
Color image information is recorded by converting the color image signal formed by reading the color image information using an image reading means into an optical signal and electrostatically developing the color image information on the image forming body. In the image processing device, by rotating the image forming body once for each of a plurality of color signals separated from the color image signal, the electrostatic charge /J(i
The image forming apparatus is characterized in that it has a plurality of developing units that perform image forming and development, and the timing to start writing on the image forming body is selected based on a drum index signal obtained in synchronization with the rotation of the image forming body. It is.

[Operation The cocolor image information is read by an image reading means such as a CCD and converted into a color image signal. The color image signal is converted into IX number of color signals (
In the example, the colors are separated into three colors (red, blue, and black).

An electrostatic latent image is formed by the separated color No. 48. The writing timing of the electrostatic latent image, that is, the color signal, is regulated based on the index signal obtained from the drum. The writing timing shall be controlled each time the color signal is written;
Therefore, even if images are recorded overlapping each other, the registration will not deteriorate. Even if the load on the drum fluctuates, it does not change as well.

[Embodiment] Hereinafter, an example of a color image processing apparatus according to the present invention will be described in detail with reference to FIG. 1 and subsequent figures.

FIG. 1 shows a schematic configuration of a system in a color image processing apparatus according to the present invention.

Color image information such as a manuscript is read by an image reading device 10,
In addition to being converted into a color image signal, A/D conversion processing,
By performing other image processing, the image data is converted into image data with a predetermined number of pits, for example, image data with 16 gradations (◯ to p).

The image data can be separated into a plurality of color signals by the color signal forming means 20. In this example, as multiple color signals,
Although the case where three colors of red No. 43, green signal, and black signal are used is shown, it is easy to understand that other colors (separated into three colors) can also be used.

The separated color signals are sequentially binarized in a binarization circuit 30. In the embodiment, it is converted into binary dither using a dither matrix having a predetermined threshold value.

The dithered image can be supplied to the output device 100 via the interface circuit 40. The interface circuit 40 is used to control the output state of dithered images, the transmission of test patterns, and the like.

As the output device 100, a laser recording device or the like can be used. When a laser recording device is used, the dithered image is converted into a predetermined optical signal, and this is converted into a predetermined optical signal based on the binary data of the dithered image. Modulated. Therefore,
Although the signal modulation in this example is internal modulation, external modulation may equally well be used.

An electrostatic latent image is formed for each color by the light No. 18 obtained from the output device 100. After the electrostatic latent image, development processing is performed for each color, and then a fixing processing is performed, so that the desired image is formed on the recording paper. A color image will be recorded.

Processing from the image reading device 10 to the output device 100 described above is performed according to a predetermined algorithm based on command signals sent from the two control units 200 and 250. Therefore, microcomputers are used for both control sections 200 and 250.

The first control section 200 controls the main body of the image processing apparatus, and the second control section 250 mainly controls peripheral devices provided for image reading.

Note that 99 indicates a system bus through which these various command signals are exchanged.

Therefore, in addition to sending out the various command signals mentioned above, the first and second control sections 200 and 250 also control the various hardware for image reading and the color copying machine attached to the output device 100. are executed according to a defined sequence.

Next, a specific example of such a color image processing device will be explained.

First, an easy-to-understand color copying machine suitable for applying the present invention will be explained with reference to FIG. 2 and subsequent figures.

A color copying machine of this type attempts to record a color image by separating color information into approximately three types of color information. In this example, the three types of color information to be separated are black BK,
Red R and blue B are illustrated.

In FIG. 2, 60 is an example of a main part of a color copying machine, and 61 is a drum-shaped image forming body, on the surface of which a photoconductive photoreceptor surface layer such as OPC (organic photoconductor) is coated. It is possible to form an electrostatic image (electrostatic latent image) corresponding to the optical image.

The following members are sequentially arranged on the circumferential surface of the image forming body 61 in the direction of rotation thereof.

The surface of the image forming body 61 is charged in the - direction by the charger 62, and the surface of the image forming body 61 charged in the - direction is subjected to image exposure based on each color separation image (the optical image is 64). ) is carried out. After the image is exposed, it can be developed using a predetermined developing device. The developing devices are arranged in a number corresponding to the color separated images.

In this example, the developing device 6 filled with red toner developer
5, a developing device 66 filled with blue toner developer,
A developing device 67 filled with a black toner developer is sequentially disposed facing the surface of the image forming body 61 in this order toward the rotation direction of the image forming body 610.

The developing devices 65 to 67 are sequentially selected in synchronization with the rotation of the image forming body 61. For example, by selecting the developing device 67, toner adheres to an electrostatic image based on a black color separation image, thereby producing a black color. The separated images are developed.

A pre-transfer charger 69 and a pre-transfer exposure lamp 90 are provided on the developing device 67 side, and these make it easier to transfer the color image to the recording medium P and to make it easier to separate the recording medium P from the image forming body 61. ing.

However, these pre-transfer charger 69 and pre-transfer exposure lamp 90 are provided as necessary.

The color image completely developed on the image forming member 61 is transferred onto the recording member P by the transfer device 91. Transferred recording body P
A fixing process is performed by a fixing device 92 at a subsequent stage, and then the recording medium P is discharged.

Note that the static eliminator 93 can be one of a static elimination lamp and a corona discharger for static elimination, or a combination of both, as required.

The cleaning device 94 is composed of a cleaning blade, a magnetic brush, a fur brush, etc., and is used to remove residual toner adhering to the drum surface after the color image of the image forming member 61 has been transferred.

It is well known that this removal operation is completed by the time the developed surface is separated from the surface of the image forming member 61.

As the charger 62, a scorotron corona discharger or the like can be used. This is because stable charging can be applied to the image forming body 61 and a constant surface potential can be obtained, with little influence from previous charging.

As the image exposure 64, image exposure obtained by a laser beam scanner is used. In the case of a laser beam scanner, clear color images can be recorded, as will be described later. The image exposure means shown in FIG. 3 is an example of this laser beam scanner (optical scanning device) 80.

The laser beam scanner 80 has a laser 81 such as a semiconductor laser, and the laser 81 is controlled on and off based on a color separation image (for example, binary data). A laser beam emitted from the laser 81 enters a mirror scanner 85 made of an octahedral rotating polygon mirror via mirrors 82 and 83. A laser beam is deflected by this mirror scanner 85 and irradiated onto the surface of the image forming body 61 through an FE lens 87 for imaging.

88 and 89 are cylindrical lenses for correcting inclination angles.

The laser beam is directed to the image forming body 6 by the mirror scanner 85.
1 is scanned at a constant speed in a predetermined direction a, and such scanning results in image exposure corresponding to a color-separated image.

Note that the collimator lens 86 is used to adjust the beam diameter on the image forming body 61 to a predetermined diameter.

As the mirror scanner 85, a galvanometer mirror 1 optical crystal deflector or the like can be used instead of the rotating polygon mirror.

Since the developing units 65 to 67 have almost the same configuration, the configuration of the developing unit 65 will be explained.

FIG. 4 shows an example of the developing device 65.

In the figure, 70 is a housing, 71 is a toner replenisher, 72 is a sponge roller, 73a and 73b are toner stirring members, 74 is a scraper, 75 is a developing sleeve, and 76 is a magnet body (3! magnet). , 78 is an H-cut board, ? 9c is a resistor? 9b is AC power supply,? 9a is a DC power supply.

The toner supplied from the toner replenisher 71 is sent to a developing section consisting of a developing sleeve 75 and a magnet 76 by the action of a sponge roller 72 and stirring members 73a and 73b. A layer of developer 77 made of toner and carrier whose thickness is regulated to a constant level by a cut plate 78 is formed on the developing sleeve 75, whereby the latent image formed on the surface of the sex-forming body 61 is fully developed. .

After development, the developer on the surface of the sleeve 75 is removed by the scraper 7.
scraped off by 4.

Note that the clockwise arrow indicates the moving direction of the developer, and the counterclockwise arrow indicates the rotating direction of the magnet body 76.

Is there a resistor in the developing sleeve 75? An alternating current signal of a predetermined level superimposed on the direct current signal is applied via 9c, and thereby a predetermined developing bias is applied between the developing sleeve 75 and the image forming body 61.

In addition, regarding the phenomenon that is repeated at least from the second time onwards to superimpose color toner images, it is necessary to ensure that the toner that has adhered to the image forming body 61 due to the previous development is not shifted during the subsequent development. . In this sense, such development is preferably performed under non-contact jumping development conditions.

FIG. 4 shows a type of developing device that performs development based on such non-contact jumping developing conditions.

As the developer, it is preferable to use a so-called two-component developer in which a non-magnetic toner and a magnetic carrier are thoroughly mixed. This is because this two-component developer has a clear color and is easy to charge on the toner side (distribution).

As the image reading device 10, one having a configuration as shown in FIG. 5 can be used.

In the figure, color image information (optical image) of a document 1 placed on a mounting table IA is separated into two color separated images by a dichroic mirror 2.

In this example, the image is separated into a color-separated image of red R and a color-separated image of cyan Cy. Therefore, the cutoff of the dichroic mirror 2 used is about 600 nm. As a result, the red component becomes transmitted light, and the cyan component becomes reflected light.

The color separation images of red R and cyan Cy are respectively supplied to image reading means 3 and 4 such as CCD, and the red component
And image No. 43 containing only the cyan component cy can be output.

FIG. 6 shows the relationship between the image signals R, cy and various timing signals necessary for image output, and shows the horizontal effective area (3
No. (H-VALID) (C in the same figure) 4. tCCD3.4
The image signals R, Cy! shown in F and G of the same figure correspond to the maximum original reading radiation W of . , i' can be read out in synchronization with the synchronous clock CLK (E in the same figure).

These image signals R and cy are supplied to the A/D converter 5 via a normalizing amplifier (not shown), so that they can be converted into digital signals of a predetermined number of bits.

Shading correction is performed during A/D conversion. Therefore, a memory 6 for shading correction is prepared, and one line of white image data is extracted from outside the image reading area, stored in memory, and used as data for shading correction. For this reason, the memory 6 is read out in synchronization with the clock of the CCD drive pulse generation circuit 7. The generation circuit 7 is also provided with a clock generator 8 . The timing of the memory is determined by an index signal for starting scanning which can be supplied to the generation circuit 7 and the second control unit 250.
It can be regulated by the printing section signal from.

Digital color image No. 43 is supplied to the next stage color separation circuit 150, where it is separated into a plurality of color signals necessary for color image recording.

In the above example, it is a simple recording device that records a color image in three colors: red, R, blue, and black.
The color separation circuit 150 receives these three color signals R, B, and BK.
It can be separated into .

A specific example of color separation will be described later.

The color signals R, B, and BK are supplied to a ghost canceller 9, where a ghost removal process is performed to cancel ghost signals generated in the main scanning direction and the sub-scanning direction.

As shown in FIG. 7, the main scanning direction for the original 1 is the line direction (horizontal scanning direction) of the CCDs 3 and 4, and the sub-scanning direction is the moving direction (vertical scanning direction) of the CCDs 3 and 4. direction).

Color No. 4g R, B, BK after ghost removal is color selection circuit 1
60, one color signal is selected per rotation of the image forming member 610.

This is because, as mentioned above, an image forming process is adopted in which one color image is developed per rotation of the image forming body 61, and the image forming process is synchronized with the rotation of the image forming body 61. The developing devices 65 to 67 are sequentially selected, and the color signals corresponding to the selected developing devices are sequentially sent to the color selection circuit 16.
0 will be selected.

Selection signals 01 to G3 for color signals are sent to the second control unit 25.
0 (second microcomputer). The output states of the selection signals G1 to G3 differ depending on the case of three-color recording, that is, the normal recording mode, and the case of monochrome recording, that is, the color-specified recording mode.

Note that color separation processing for separating color signals from a color original into three color signals is executed every rotation of the image forming body 61.

The above-mentioned color separation (color separation into three color signals from two colors) is performed based on the following idea.

Figure 8 schematically shows the spectral reflection characteristics of a color chart of color components, in which Figure A shows the spectral reflection characteristics of achromatic colors, Figure B shows the spectral reflection characteristics of blue, and Figure 8 shows the spectral reflection characteristics of blue. C shows red spectral reflection characteristics. The horizontal axis is the wavelength (nn
+), and the vertical axis is relative sensitivity (%).

Now, if the level of the red signal R normalized to white is VR, and the level of cyan No. 13 Cy is VC, then these signals V
By creating a coordinate system from R and VC, red, blue, and black colors can be separated based on the created color separation map.

When determining the coordinate axes, the following points need to be considered.

■In order to express halftones, the reflectance (reflection density) of original 1, which corresponds to the brightness signal of the television signal, is
Introduce the concept of

II. Introduce the concept of color difference (including hue, again) such as red and cyan.

Therefore, the following may be used as the luminance signal information (for example, a 5-bit digital signal) and the color difference signal information (also a 5-bit digital signal).

Luminance signal information = VR + VC (1) However, O≦VR≦1.0 (2) O≦VC≦1
．． 0 (3) 0≦VR+VC≦2.0
(4) The sum of VR and VC (VR+VC) corresponds to the black level (=0) to the white level (=2.0), and all colors exist in the range from 0 to 2.0.

Color difference signal information = VR/ (VR+VC) or VC/
(VR+VC) (5)j:I Tj E
In this case, the proportion of the red color VR1 cyan level VC included in the overall level (VR+VC) is constant. Therefore, VR/ (VR+VC)=VC/ (VR+VC)=0
．． 5 (6) becomes.

On the other hand, in the case of chromatic colors, 0.5<
VR/ (VR+VC) ≦1.0 (7) 0≦V
C/ (VR+VC)<0.5 (8) For cyan colors, 0≦VR/ (VR+VC)<0.5 (9) 0.
It can be expressed as 5<VC/(VR+VC)≦1.0 (10).

Therefore, the coordinate axes are (VR+VC) and VR/(VR
+VC), MoL < C (VR+VC) VC/
By using a coordinate system having two axes (VR+VC), chromatic colors (red and cyan) and achromatic colors can be clearly separated just by level comparison processing.

In FIG. 9, the vertical axis shows the luminance signal component (VR+VC), and the horizontal axis shows the color difference signal component VC/(
The coordinate system when VR + VC) is taken is shown.

If VC/(VR+VC) is used as the color difference signal component, areas smaller than 0.5 will be red R, and areas larger than 0,5 will be cyan Cy. Achromatic colors exist in the vicinity of color difference A3 information=0.5 and in areas with little luminance signal information.

FIG. 10 shows a specific example of a color separation map in which colors are classified according to such a color separation method.

A ROM table is used for the color separation map, and the illustrated example shows an example in which the map is divided into 32×32 blocks. Therefore, as the number of address bits for this ROM table, 5 bits are used for the row address and 5 pits are used for the column address. This ROM table stores quantized density corresponding values obtained from the reflection density of the original.

FIG. 11 shows the color separation circuit 150 (A in the figure) and the color selection circuit 160 (B in the figure) for realizing such color separation.
It is a system diagram showing an example.

To explain from A in the figure, terminals 150a and 150b have 3 terminals.
A red signal R and a cyan signal cy before color separation are supplied, and processing such as gradation conversion and γ correction is executed in an arithmetic processing circuit 151.

The data after the arithmetic processing can be used as an address signal for the memory 152 where the arithmetic result of (VR+VC) for obtaining luminance signal data is stored, and also as an address signal for the memory 152 where the arithmetic result of the color difference signal data VC/(VR+VC) is stored. It is used as an address signal for 153.

Each output of these memories 152 and 153 is a separate memory (
ROM configuration) is used as an address signal for 154 to 156. The memories 154 to 156 can be used to store a data table in which data of the color separation map shown in FIG. 10 is stored for each color.

The memory 154 is for the black signal BK, the memory 155 is for the red signal R, and the memory 156 is for the blue signal B.

As is clear from the color separation map shown in FIG. 10, by detecting the levels of the red signal R and cyan No. 48 Cy, the three color signals R of red, blue, and black are extracted from the color information signal of the color document. ,B.

It is possible to separate and output BK.

Each of the memories 154 to 156 outputs density data (4-bit configuration) regarding each color signal and color code data of 2-bit configuration at the same time.

Density data and color code data are each sent to synthesizer 1 in the latter stage.
57,158. The combined density data and color code data are supplied to the ghost canceller 9, where ghost No. 48 is removed.

Each data after ghost removal is supplied to a color selection circuit 160 shown in the 11th [IB].

The color code data supplied to the terminal 161 is supplied to a decoder 164 to decode the color code, and the decoded output is supplied to OR circuits 166-169. Similarly, color selection signal 0 supplied to terminal 163
The data contents of 1 to G3 are decoded by the decoder 165, and the decoded outputs are supplied to the plurality of OR circuits 166 to 169 described above to generate signals ranging from red to black and including all of these colors (all colors). It is possible to select any color signal among them.

The select signal for color No. 43 outputted from each OR circuit 166 to 169 is supplied to the density signal separation circuit 170 as a density selection signal. The above-mentioned density data is supplied to the density signal separation circuit 170 through the terminal 162, and this density data is selected in response to the above-mentioned select signal.

The selected density data is supplied to the binarization circuit 30.

The color selection signals 01 to G3 correspond to the separated color signals, and in the normal color recording mode, three-phase gates 13 Nos. 01 to 03 synchronized with the rotation of the image forming body 61 are formed (12th Figure G~■). At the same time, developing biases shown in FIGS. 12C to 67 are also applied to the image forming body 61.
The toner is supplied to each of the developing units 65 to 67 in synchronization with the rotation of the developer.

As a result, exposure and development processing steps are sequentially performed with exposure processes I to 11 ((FIG. F) for each color.

On the other hand, in the case of color specification recording mode, there is a single image forming process that has been completely specified. Therefore, the three selection signals G1 to G3 are obtained in phase regardless of the designated color signals (G to I in the figure). The example shown in No. 13 [21] is a case where red is specified.

At the same time, a developing bias is supplied only to the corresponding developing device 65 (D in the figure), and this becomes in operation. Therefore, since only the developing device 65 containing red toner (developer) is driven, an image can be recorded in red regardless of the color information of the color original 1.

Even when specifying another color (black or blue), the image forming process is the same, so a detailed explanation thereof will be omitted.

FIG. 14 is a system diagram showing an example of the binarization circuit 30.

In the figure, the threshold table 32 includes a main scanning counter 33 that counts write clocks, a sub-scanning counter 34 that counts horizontal synchronization signals, and outputs predetermined threshold data based on the count values of these counters 33 and 34. It has a matrix (ROM configuration) 35.

If the document to be read is a line drawing, the threshold data is
Data of a constant threshold value corresponding to the concentration is used. On the other hand, when the original is a photographic image, binarization using the dither method is preferable, and in that case, the dither matrix is used as threshold data. About three types of dither matrices are prepared depending on the density of the original, and these are selected depending on the density of the original.

The image data output from the color selection circuit 160 is compared with predetermined threshold data obtained from the threshold value table 32 in the comparison circuit 37 for binarization processing, and is binarized for each pixel.

Note that it is also possible to perform enlargement/reduction processing on the original image data before performing the binarization processing.

Enlargement/reduction processing in the main scanning direction is performed by electrical signal processing, and enlargement/reduction processing in the sub-scanning direction is performed by changing the moving speed of the CCD 3.4 or the image information while keeping the exposure time of the CCD 3.4 constant. Let's do it.

An image processing circuit is provided for enlarging/reducing processing in the main scanning direction. Although detailed explanation thereof will be omitted, an interpolation method can be used for enlarging/reducing.

Interpolation is an image processing method that attempts to obtain enlarged or reduced images by increasing or thinning data related to a pair of adjacent original image data based on the levels of the adjacent pair of original image data. .

For example, when enlarging an original image by two times, as shown in FIG. , D2 are used as image data after enlargement processing, that is, interpolation data S.

Enlargement/reduction is processed in real time. Therefore, the interpolation data mentioned above is stored in advance in a ROM or the like, and the interpolation data S can be addressed using a pair of original image data or the like.

Furthermore, in color separation, color ghost processing, and the like, these data are processed without being stored in a RAM or the like, so real-time processing is possible, which allows speeding up and downsizing.

FIG. 16 shows the interface circuit 40.

The interface circuit 40 is composed of a first interface 41 that receives binary data, and a second interface 42 that receives binary data sent therefrom.

The first interface 41 includes a timing circuit 43
Horizontal and vertical valid area signals (H-VALI()) and (V-VALID) are supplied from the counter clock circuit 44, and a clock of a predetermined frequency (6Ml+2 in this example) is supplied from the counter clock circuit 44.

Generally, a CCD drive clock is supplied.

As a result, binary data is sent to the second interface 42 in synchronization with the CCD drive clock only during the period when the horizontal and vertical effective area signals are generated.

The counter clock circuit 44 generates a main scanning side timing clock synchronized with the optical index signal.

The second interface 42 is an interface for selecting the binary data that has been sent out from the first interface 41 and other image data and sending it to the output device 100 side.

Other image data refers to the following image data.

The first is test pattern image data obtained from the test pattern generation circuit 46, and the second is test pattern image data obtained from the test pattern generation circuit 46.
Thirdly, it is control data obtained from the printer control circuit 45.

The test pattern image data is used when inspecting image processing, and the batch image data for toner density detection is used during batch processing.

Both the test pattern generation circuit 46 and the batch circuit 47 are driven based on the clock of the counter clock circuit 44, thereby adjusting the timing with the binary data sent from the first interface 41.

The binary data output from the second interface 42 will be used by the output device 100 as a modulation signal for the Lebe beam.

FIG. 17 shows a peripheral circuit of the output device 100. The semiconductor laser 81 is provided with a drive circuit 101, and the above-mentioned binary data is supplied to this drive circuit 101 as a modulation signal. The laser beam is internally modulated. The timing circuit 111 is set so that the laser driving circuit 101 is in the driving state only in the horizontal and vertical effective area sections.
It is controlled by a control signal from 02. Further, a signal indicating the amount of light of the laser beam is fed back to the laser drive circuit 101, and the driving of the laser is controlled II so that the amount of light of the beam is constant.

The mirror scanner 85 is driven by a polygon motor 104, and the scanning start point of the laser beam deflected by the mirror scanner 85 is detected by an index sensor 105, and the index signal is converted into a voltage signal by an I/V amplifier 106. Afterwards, this index signal is supplied to the counter clock circuit 44, etc., and the timing of optical main scanning can be adjusted.

Note that 103 is a polygon motor drive circuit, and its on/off signals are supplied from the timing circuit 102.

The various devices or circuits described above are
All are controlled by control units 200 and 250. The explanation will start from the second control unit 250.

As shown in FIG. 18, the second control unit 250 mainly controls the image reading system and its peripheral equipment, and 251 is a microcomputer (second microcomputer) for controlling the optical drive. Various information signals are exchanged with the main body control microcomputer (first microcomputer) 201 through serial communication. Further, the optical scanning start signal sent from the first microcomputer 201 is directly supplied to the interrupt terminal of the second microcomputer 251.

The second microcomputer 251 generates various command signals in synchronization with a clock of a predetermined frequency (12Mflz) obtained from a reference clock circuit 258.

The second microcomputer 251 detects data for shading correction and sends a command signal for storing this to the shading correction memory 6, as well as a selection signal for density selection to the threshold table 32. The color selection signal for color recording is sent to the color selection circuit 16.
0.

The second microcomputer 251 further outputs the following control number 48.

First, a control signal for turning on and off the drive circuits of the CCDs 3 and 4 is supplied to their power supply control circuits (not shown). Second, a predetermined control signal can be supplied to a lighting control circuit 254 for a light source (such as a fluorescent lamp) 255 for irradiating the document 1 with necessary light. Third, image reading device 1
A drive circuit 252 that drives a stepping motor 253 for moving the movable mirror unit provided on the 0 side.
Control No. 43 is also supplied to Fourth, heater 257
A control signal is also supplied to a control circuit 256 for the control circuit 256 .

Note that the second microcomputer 251 receives data indicating the light amount information of a light source 255 such as a fluorescent lamp and the home position.

The first microcomputer 201 is mainly used to control the color copying machine. FIG. 19 shows an example of an input system and an output system from a color copying machine.

The operation/display unit 202 receives input data such as magnification designation, recording position designation, and recording color designation, and displays the contents thereof.

As the display means, an element such as an LED is used.

The paper size detection circuit 203 can be used to detect and display the size of the cassette paper fully loaded in the tray, or to automatically select the paper size according to the size of the document.

The rotational position of the drum 610, which is an image forming member, can be detected by the drum index sensor (detection means) 22 degrees, and the timing of the electrostatic processing process is controlled by the index signal. Details of the drum index detection system will be described later.

The cassette zero sheet detection sensor 221 detects whether there are no sheets in the cassette. Similarly, the manual feed zero sheet detection sensor 222 can detect the presence or absence of paper for manual feed in the manual feed mode.

The toner density detection sensor 223 detects the density of toner on the drum 61 or after fixing.

Further, the remaining amount of toner in each of the developing units 65 to 67 is individually detected by three remaining toner amount detection sensors 224 to 226, and when toner replenishment is required, a toner replenishment display provided on the operation unit is displayed. It can be controlled so that the element lights up.

- The time stop sensor 227 is for detecting whether or not paper is correctly fed from the cassette to the second paper feed roller (not shown) side during use of the color copying machine.

Contrary to the above, the paper ejection sensor 228 is used to determine whether or not the fixed paper is correctly ejected to the outside.

The manual feed sensor 229 is used to detect whether a manual feed tray is set. If it is set, it will automatically switch to manual feed mode.

The sensor output obtained from each sensor as described above is taken into the first microcomputer 201, and the necessary data is displayed on the operation/display unit 202, and the driving state of the color copying machine is controlled as desired. Ru.

In the case of color copying, in addition to the red and blue developing motors 230, an existing motor 231 is provided, both of which are controlled by command signals from the first microcomputer 201. I? i], the driving state of the main motor (drum motor) 204 is controlled by a drive circuit 205 having a PLL configuration, but this drive circuit 205 also has its driving state controlled by a control signal from the first microcomputer 201. It will be controlled.

During color development, it is necessary to apply a predetermined high voltage to a developing device during development. Therefore, a high voltage power supply 232 for charging, a high voltage power supply 233 for development, a high voltage power supply 234 for transfer and separation, and a high voltage power supply 2 for the toner receiver.
35 are respectively provided, and a predetermined high voltage can be applied to them when necessary.

Note that 237 is a cleaning roller drive unit, 238 is a first paper feed roller drive unit, 239 is a second paper feed roller drive unit, and 236 is a cleaning pressure release motor. Roughly speaking, 240 is a drive unit for the separation claw.

The second paper feed roller is used to transport the paper transported by the first paper feed roller to the electronic calendar image formed on the drum 61.

The fixing heater 208 is controlled by a fixing heater on/off circuit 207 according to a control signal from the first microcomputer 201 .

The fixing temperature is read by the thermistor 209, and the first microcomputer 2
Regulated by 01 (distributed).

206 is a clock circuit (approximately 12 Mtlz).

A nonvolatile memory 210 attached to the first microcomputer 201 is used to store data that should be saved even when the power is turned off. for example,
This includes total counter data and initial setting values.

In this way, the first and second microcomputers 20
1.251, various controls necessary for color image processing are executed according to a predetermined sequence.

FIG. 20 is a diagram showing an example of a drum index signal detection system, in which an index element 95 shaped like a disc is attached to one end of the rotating shaft 61A of the drum 61 so as to be rotationally integrated with the drum 61. It will be done. In this example, a U-shaped cut 97 is formed in a part of the circumferential surface of the index element 95 with a predetermined depth and radius (FIG. 21).
.

On the other hand, an index sensor (detection means) 96 is provided opposite to the circumferential surface of the index element 95, in this example, so as to straddle a part of the circumferential surface.

As a result, a pulse-like index signal (FIG. 34A) is obtained from the index sensor 96 every time the notch 97 of the index element 95 passes, so that the rotational position of the drum 61 can be detected by this index No. can.

It should be noted that such a drum index element 95 can be placed on the drum 6 as long as it does not interfere with the conveyance of the recording paper.
It may be provided on a part of the circumferential surface of 1.

Next, a series of processes in color recording will be explained in detail with reference to FIGS. 22 to 24. In this embodiment, in addition to multicolor recording (three colors of blue, red, and black), it is also possible to record in a specified color (single color) in a predetermined image pad readout area from the outside. Multicolor recording will be explained with reference to FIGS. 22 and 23.

However, the explanation thereof partially overlaps with the explanation of FIGS. 12 and 13.

In FIGS. 22 and 23, section F1 indicates the section from when the main power of the apparatus is turned on until when the copy button is operated. Section F2 is a section for pre-rotation processing of the image forming body (hereinafter referred to as drum).

Section I is a blue development section, section II is a red development section, and section I11 is a black development section. In other words, section ■ is the section for post-rotation processing.

Further, the numbers shown in the figure indicate the count value of a drum counter or the count value of another counter such as a pre-rotation counter which will be described later.

When the main power is turned on, the main motor such as the drum motor 204 rotates for a predetermined period of time, and when the copy button is operated, the main motor rotates (FIG. 22C), and the index element 95 attached to the drum 61 is rotated. When the index sensor detects, the drum counter is cleared (
Figures A and B).

Subsequent processing operations are executed based on the count value of this drum counter.

The lengths (times) of sections 1 to (2) are the same, and in this example, the count value is 778 and the drum 61 completes one rotation.

When the pre-rotation section F2 is reached, charging of the drum 61 is started (D in the figure). Drum charging continues until the first exposure is completed (see section IV).

In the pre-rotation section F2, the pre-transfer lamp is turned on for a certain period of time (up to the middle of the blue development section I) from approximately the middle of the pre-rotation section F2, and pre-processing for color development is executed.

When entering the current development section from blue to black, the magnet bodies 76 and the developing sleeve 75 provided in the current stand 65 to 67 are rotated in the corresponding sections, and the development bias is adjusted in synchronization with the timing of these rotations. (Figure F-
K).

The cleaning blade 94 is pressed in synchronization with the rise of the drum index signal in the previous rotation section F2, and
The toner adhering to the drum 61 is removed (L in the same figure), and the removal is carried out when the drum 61 rotates once after the pressure bonding (M in the same figure), but even after this toner removal, some toner remains on the drum. In some cases, the toner may scatter when the blade is released, so the cleaning roller starts operating slightly after the blade is released to remove the remaining toner (see figure 1). N).

Immediately before the blue development period I, the first paper feed roller rotates and the recording paper is completely conveyed to the second paper feed roller side (FIG. 0). 1st
The paper feed roller is provided to convey the paper in the cassette, and the paper conveyed by the first paper feed roller is conveyed to the drum 61 side by driving the second paper feed roller. Ru.

The transport timing is the final exposure process section (the exposure process 111 in the figure). (Figure P).

The paper feeding operation by the first paper feeding roller stops when the recording paper reaches a temporary stop sensor provided just before the second paper feeding roller, and when the second paper feeding roller is fully driven and the recording paper passes,
The sensor output becomes zero (S in the figure).

The transfer process is executed a little later than the drive of the second paper feed roller, and in synchronization with this, the drum 61 is
In order to prevent the paper from wrapping around the paper, a predetermined AC voltage is applied to the paper separation electrode (Q in the same figure).

After the temporary stop sensor 227 falls to zero, the development and fixing processes are completed, and the paper ejection sensor 228 then detects the ejection state of the sheet after fixing (see the drawing).

In the case of color recording, toner density detection can be accomplished for each development process. The density detection timing is determined by the count value of each detection counter for blue to black (U2 to U4 in the same figure)
. All of these counters are reset based on the timing when writing the density detection patch starts, and the blue counter is reset when the count value of the drum counter is 706, and the toner density can be detected when the count value after reset is 602. .

Similarly, the red counter is reset at 707, and the black counter is also reset at 707.

Here, the toner density is detected with reference to a certain specific image area. Therefore, the patch signal for density application shown in FIG. 2 (for example, an image signal corresponding to an image area of 8 x 16 mIII size) can be used, and after a predetermined period has elapsed since the patch signal is obtained, a signal for toner density detection is sent. (R in the same figure) is completely output, and the image density of that specific area is detected.

The pre-rotation counter is set to Clearance 1 at the timing when the first drum index signal is input after copy-on.
When the count value reaches 1266, the pre-rotation process ends (Ul in the figure).

When the main power is turned on, the polygon motor 104 that drives the mirror gunner 85 is also driven at the same time, so that the mirror gunner 85 can be rotated at a constant speed at all times ((2) in the figure).

Image data necessary for image recording is transmitted at the following timing. In other words, the video gate is set to "1" in synchronization with the blue counter, and is set to "0°" at the same time as the black laser writing ends (W in the same figure), and the video gate is set only during the period of "1°". The image data can now be sent to the output device 100 side.

The vertical valid area signal (V-VALID) is sent out in each development processing step so that it remains valid for a certain period (if the recording paper is A4 size, the period until the count value reaches 528) (see figure Y).

Note that a copy signal is sent from the first microcomputer 201 on the main body side to the second microcomputer 251 for controlling the optical system (AA in the same figure).
, a start signal for optical scanning is output. This optical scanning signal enters the start state at the falling edge from 1'' to 0'' (FIG. BB).

Furthermore, in the case where the image reading device 10 is configured to move a movable mirror unit to which a light source, which is part of the image reading means, is attached, a home position signal indicating the home position of this optical system is used for each development process. For each step, the data is sent from the second microcomputer 251 to the first microcomputer 201 (
Same figure CC).

The first microcomputer 201 receives the home position signal, performs the next exposure process, and then sends copy R45 (AA in the figure) to the second microcomputer 251 (DD in the figure). .

The above is a timing chart showing an outline of multi-color recording.

When recording the original image with externally specified colors, use the second
The timing chart is as shown in FIG. 4, and only the image processing related to the designated color is executed, and none of the other image processing steps are completed.

Therefore, a detailed explanation of each operation of this monochromatic image processing step will be omitted.

However, the image processing steps shown in FIG. 24 are for a case where an image is recorded in black (normal black and white copy).

The series of color image processing as described above is performed by the first and second microcomputers 201 and 25 described above.
The old H is sold out by 1.

Next, the system (wholesale program) for executing such processing will be explained in detail with reference to FIG. 25 and subsequent figures.

For convenience of explanation, a flowchart for realizing the general processing operation of color recording in the entire apparatus will be described with reference to FIG. 25.

In FIG. 25, 300 is a flowchart showing an example of a control program stored in a ROM memory (not shown) of the first microcomputer 201. In FIG.

First, when the main power is turned on, this control (wholesale program operates and transitions to a mode in which the initial state of device processing operation is achieved. 61 is performed (step 302).This cueing process is performed so that the drum 61 reaches a predetermined rotational position by using the index number 48 obtained from the index element provided on the drum. This refers to rotation control processing.

Next, warm-up processing such as fixing processing and lighting of the light source (step 303), input data processing such as color specification input from the scanning/display unit and number of copies specification (step 304), and temperature control in the heater for fixing. Processing (step 305) and idling jam processing such as copy waiting and paper jam processing (step 306) are executed in this order.

Whether or not these warm-up processes are completed is determined in the next step 307. If the warm-up processes are not completed, the process returns to step 303 and the same process is executed again, and the warm-up processes are completed. Occasionally, a check is made to see if a copy button provided on the operation/display section has been operated, and if no copy operation has been performed, the process returns to step 304 and enters a standby state for input data (step 308).

When the copy button is operated, various input information such as color specification, density specification, paper size specification, etc. input on the operation/display side is serially transmitted from the first microcomputer 201 side to the second microcomputer 251 side. At the same time (step 309), it is determined whether the copy mode is single color specification (hereinafter referred to as 1 scan copy), all three colors, that is, multicolor specification (hereinafter referred to as 3 scan copy), or 2 color specification (hereinafter referred to as 2 scan copy). is determined (step 310).

When performing 1 scan copy, the 1 scan copy processing routine (subroutine configuration) of step 320 is called, and when performing 2 or 3 scan copy, the 2 or 3 scan copy processing routine configured as a subroutine is called (step 320). 360).

When the processing of these subroutines is executed and the process returns to the main routine again, the paper size, (0 degree processing, fixing heater processing and operator, and jam processing) are performed.
Step 311. ~313), it is determined whether or not the copying has been completed in Q7a (step 314). If the copying has not been completed, the process returns to step 310; if the copying has been completed, the process returns to the input data processing step 304; Similar processing steps will be performed.

FIG. 26 is a flowchart showing an example of one-scan copy processing.

When the 1 scan copy routine is called, a flag indicating the number of copies is checked (step 321). This flag is set each time the recording paper is fed inward to the second paper feed roller. If the number of copies flag is not set, the process moves to step 325. When the flag is set, data on the number of copies is processed (step 3).
22).

When the number of copies does not reach the preset number of copies (set number), the process moves to step 325, a paper feeding and conveyance processing step, but when the number of copies matches the set number, the end flag for the number of copies is set. (Step 324).

When the paper feeding and conveying process is completed, the laser 81 is used for the laser 81 injecting process and the developing units 65 to 65 . High voltage power supply 232 to 2 applied to 67
35 processing is executed (steps 326 and 327).

After determining the presence or absence of such processing, development processing can be completed (steps 328 to 336). In the development processing step, the timing of each development start is detected.

In the case of one scan copy, development processing is executed only for the designated color, but for convenience of explanation, the case where the color red is designated will be explained. In this case, the start timing of each development process is determined regardless of the color designation.

For this reason, first, the red development processing start timing can be determined, and when it matches the red development processing start timing, the presence or absence of the red copy flag (actually, the input specification on the operation/display section is checked) is checked. When the red copy flag is set, red development starts (steps 328 to 330).

When this development process is completed, the next step is to start the blue and black development process, but since the specified color is only red, the blue and black development process steps are skipped in this example, and step 337 is started. The development off timing can be clearly determined.

If it is time to turn off development, the development processing is turned off (steps 337 and 338), and the presence or absence of a reverse copy is determined. If a reverse copy is specified, a reverse bit is set in the register, and if no reverse copy is specified, the reverse bit is set in the register. If so, reset the invert bit of the register (step 340).
, 341).

Next, if the number of copies does not match the number of set copies,
Since the end flag is not set to 1, in this case, it is determined whether the optical scanning system is at the home position (step 345), and if it is at the home position, the start flag for the next copy sequence is set at step 346. is set.

Then, the scan start output timing of the optical system is detected (step 347), and when it is the output timing, the scan start signal is sent to the second microcombi and user 251 side, and the writing timing of the laser beam is adjusted. a timer (in this example,
10m5ec timer) is restarted (step 3
48,349).

When the optical system scans from the home position to the end of the document (the loading start position), a writing start state is entered.

On the other hand, if the timer restarts, the vertical effective area signal (
V-VALID) is set, and the corresponding counter is cleared (steps 350 and 351). As a result, the image based on the red signal becomes the write mode, and based on this, the red color separation image is completely converted into an electrostatic latent image, and development processing is executed.

When the counter is cleared, it is then determined whether the end flag is 1 (step 352).

Then, as soon as the end flag is 1 (step 35
2), the post-rotation process is executed, and the drum 61
After the cue processing is performed (step 354), the process returns to the main routine.

Similar processing is performed when a color other than red is specified. If blue is specified, steps 331 to 333
When the process of steps 334 to 336 is executed, and when black, that is, the normal monochrome recording mode is specified, the processes of steps 334 to 336 are executed.

Then, until the copying operation is completed, the above-mentioned 1 scan copy processing routine 320, paper size and copy density processing routine 311, and fixing heater correction processing routine 312 are performed.
and each step of the operating jam processing routine 313 are repeatedly executed.

FIG. 27 shows an example of a control program when a 2 or 3 scan copy sequence is called.

2 or 3 When the scan copy routine is called,
The processing steps from determining the flag state of the number of copies to setting the end flag are the same as the one-scan copy sequence (steps 361 to 364).
. Next, the presence or absence of copy mode cannot be determined (Step 3
65), in the copy mode, when the optical scanning system is at the home position, the color signal to be scanned next is transmitted to the 20th microcomputer 251 side (steps 366 and 367), and the color ffl image processing routine is executed. The state of the start timing is checked, and if it is the color development processing routine start timing, the processing routine flag is set (steps 368 and 369).

If the copy mode is not in effect or if the optical scanning system is not in the home position, the process moves to the decision step of step 368.

When the processing routine flag is set, the state of the pre-rotation flag is checked, and if the flag is 1, the pre-rotation process is executed (step 37o).

371), and then shifts to a processing routine corresponding to each color. Therefore, first, the blue routine flag is checked, and if the flag is 1, blue sequence processing is performed (steps 372 and 373). Similarly below,
The red and black color processing routines can be sequentially determined while checking the respective flags (steps 374 to 377).

Therefore, in the case of multi-color, each of these color processing routines are used, but in the case of 2-scan copy,
Only color processing routines that have been specified will not be processed.

When the color processing sequence is completed, the transfer flag is checked, and if the transfer flag is set, the state of the end flag is determined after the transfer and the cleaning process of the genital organs 65 to 67 are performed, and the copy end flag is set. When the post-rotation flag is 1, post-rotation processing of the drum and cue processing of the drum, which are copy post-processing, are executed (steps 378 to 382).

By the way, when the color processing routine flag is set,
A color processing identification routine 400 shown in FIG. 28 is called.

Therefore, first, the color being scanned is determined (step 401). Initially, a scan related to blue is executed, so in that case, if the red flag is out of state and the red flag is on, and the black flag is also on, the flag for the red processing routine is set. (steps 402, 403, 405). If the black flag has not been set, a blue transfer flag is set (step 404).

If the red flag is not set, the black processing routine flag is set, and then the transfer flag is set (steps 408, 409).

When the color being scanned changes to red, the presence or absence of a black flag is checked, and if the flag is set, the process moves to step 408, but if the flag is not set, it is determined whether there is an end flag. , if that flag is not set, a flag for the next color processing routine, the blue processing routine, is set (steps 410, 411).
).

If black is being scanned and the end flag is set, the process returns to the 2nd or 3rd scan processing routine, but if not, the flag for blue processing, which is the next processing scan, is checked, and if that flag is present, At step 411, a flag for the blue processing routine is set.

When the flag is not raised, return to step 405 and
The flag for red processing Luzhin is now set.

The reason why the color identification processing routine was designed this way is because there may be two or three colors specified, so that it can be processed no matter how many colors are specified. This is because it is necessary to execute color processing while checking the specified color each time.

By the way, in the 2- or 3-scan copy mode, by rotating the drum two or three times, electrostatic images corresponding to each color are overwritten to form a predetermined color image into an electrostatic latent image, and then the fixing process is performed. will be done.

Therefore, in such a copy mode, the registration relationship between the previously developed image and the electrostatic image to be overwritten this time is very important. This is because if the registration storage controller is bad, the quality of the recorded color image will deteriorate significantly.

The quality of the registration depends on whether the scan start position of the drum for each color is always at a predetermined position.

Therefore, in the present invention, a drum scan control routine is provided to constantly monitor the drum scan start position.

FIG. 29 shows an example of such a control routine.

The rotational position of the drum 61 is determined by detecting a notch 97 of an index drum 95 which functions as an index element provided in association with the drum 61.

By detecting passage of the cut portion 97 of the index drum 95 using an optical or electromagnetic detection means 96, and by associating this detection position with an optical write start position, etc. in advance, an index signal can be detected. By simply doing this, the relationship between the writing start position and the rotational position of the drum can be regulated as desired.

This index 4 obtained once per revolution of the drum 61
When No. 8 (FIG. 34A) is successfully detected, the above-mentioned control routine, which is an index interrupt routine, is called and the control program is started. When the index interrupt starts, interrupts other than the index signal are prohibited, and the presence or absence of an optical scan prohibition flag is checked (steps 501 and 502).

This flag is set to 1 in the following cases:

In the embodiment, in the case of 1-scan copy, a sequence that starts optical scanning in synchronization with the index signal is not selected, so a flag is set in 1-scan copy mode.

In addition, in the case of pre-rotation processing and post-rotation processing, there is no need to perform processing using index signals, so even in such processing, the flag is raised. . For this reason, the flag is reset only in the 2 or 3 scan copy mode.

In the case of the 2 or 3 scan copy mode, the copy mode is checked in the next step, and if the copy mode is selected, a scan start signal for starting optical scanning is sent from the first microcomputer 201 to the second microcomputer 251. The data is sent to (steps 503 and 504). As a result, the optical system immediately starts optical scanning (FIG. 34B).

When the optical scan starts, a timer used to synchronize the writing timing is started (step 505).13 The distance from the optical scan start point to the original flii1 hidden on the mounting table IA is started. For counting, the above-mentioned timer which outputs a pulse every 10 m5ec can be used (FIG. 34C).

Synchronize the timer with the index signal like this and start!・If possible, by setting the optical system scanter 1 timing based on the timer value, the drum 6
It is possible to always match the initial rotational position of 1 and the 1-mm rotation of the optical system.

When the timer is restarted, the vertical effective area signal (V
-VALID) is set, and at the same time, the start counter of the vertical valid area signal (V-VALID) is cleared (steps 506, 507).

This start counter is used to set the laser writing start point and to set the effective reading area in the sub-scanning direction, and is incremented by pulses obtained from the above-mentioned timer.

When these processes are completed, the presence or absence of 2 or 3 scan copy mode is checked, and if this copy mode is selected, the start of pre-rotation processing is checked, and if it is pre-rotation processing, the flag is set, and then the drum counter is set. is cleared, and the inhibited state of interrupts other than index interrupts is released, and the index interrupt processing routine ends (steps 508 to 512).

In addition, when the optical scan prohibition flag is set,
The process proceeds to step 508, but since optical scanning is not performed in this state, the process proceeds to step 511.

FIG. 30 shows an example of a timer interrupt processing routine 530 for adjusting write timing.

When this interrupt processing starts, the vertical effective area signal (
Vertical effective area signal (V-VALID) is checked, and when this flag is set, the vertical effective area signal (V-VALID) is checked.
It is possible to check whether the count value of the counter ID) matches the scan start count value indicating the start point of laser writing (steps 531 and 532).
.

That is, when the index signal is obtained, the vertical effective area signal (V-VALID) start counter starts, and when the count value reaches a predetermined value (input start count value) (FIG. 34C), the laser starts. Writing of image data starts (D in the same figure). Second, if the count value of the counter matches the scan start count value, then the vertical effective area (No. 3 (V-
After VALID) has been output to the timing circuit 102, the flag of the vertical valid area signal (V-VALID) is reset (steps 533 and 534), and the process proceeds to the next step.

When the vertical valid area signal (V-VALID) flag is not set and vertical valid area No. 18 (V-VALID)
If the count value of the counter does not match the scan start count value, the process immediately proceeds to step 535.

In step 535, the count value of the prohibition counter is checked. In step 535, a signal other than the index signal is input to prevent the laser writing start point from malfunctioning due to noise generated during the time up to the start of laser writing (corresponding to period T in FIG. 34). This is also a step for prohibiting the input of (g). Therefore, the set count value of this prohibition counter is set to a count value corresponding to the period T or more.

After the count value of the vertical valid area signal (V-VALID) start counter matches the count value of the prohibition counter, the optical system can be started, so in this state, the index interrupt flag can be reset and the index interrupt flag can be reset. The interrupt prohibition is canceled (steps 536 and 537).

Thereafter, the vertical valid area signal (V-VALID) start counter is incremented, processing other than registration is executed, and the process returns to the main routine (steps 538, 539).

The control program described above relates to the first microcomputer 201. .

Next, the control program for the second microcomputer 251 will be explained in detail with reference to FIG. 31 and subsequent figures. The second microcomputer 251 is mainly used to drive the optical system f5fl.

Figure 31 is a flowchart of the main routine of the optical system.
When this control i11 program is started, first the CP installed in the second microcomputer 251 is
When U is initialized, the memory is cleared, and then the optical system's home position reset can be started.
Immediately thereafter, a timer for measuring warm-up is started, and warm-up can be started (steps 601 to 604).

When warming up has started, you can check whether the warming up has been completed, and if not, you can check whether the warming up time has arrived or not, and if the warming up is not completed even after the time is up, it will be displayed as a trouble. (Steps 605-6
07).

When the warming-up is completed, the warming-up timer is stopped, and at the same time, the light source (such as a fluorescent light) that illuminates the original is turned off (step 608).
, 609).

Next, the presence or absence of copy mode is checked, and if it is in copy mode, the light source is turned on, and the amount of light reflected from document 1 is monitored. If the amount of light is unstable, a trouble message is displayed, indicating that there is an abnormality on the monitor. If not, the ready flag is set, a ready signal is transmitted to the second microcomputer 251 side, and optical scanning is initialized (steps 6i0 to 615).

When the initialization of optical scanning is completed, the pulse count check flag is checked, and if the flag is set, the forward movement of the optical system is checked, and when the optical system is in forward movement, it is determined whether the optical system has advanced the predetermined distance t. The determination is made based on the counted value of the pulse count (steps 616 to 618).

If the above-mentioned count value is not reached, the pulse interval time is set, then the excitation pattern is set, and the current value is set to a predetermined value. Thereafter, the pulse count check flag is reset and the process returns to step 616 (steps 619 to 622).

When a predetermined number of pulses are counted, the optical system has moved forward to the maximum movement position in the sub-scanning direction, so in this case, the movement of the optical system is completed and the forward movement flag is reset (step 623). .624).

Retraction of the optical system can be determined in step 617, and when in the retraction mode, the set pulse number is checked in the same way as described above, and if not, the pulse interval time and excitation pattern are set. The process then proceeds to step 622 (steps 630 to 632).

When the set number of pulses is reached, the retraction (return) of the optical system is completed, a home position signal is transmitted to the first microcomputer 201, and then the copy mode is determined again. This copy mode determination is a step of determining whether or not continuous copying is to be performed; in the case of single copying, the light source is turned off and the process returns to step 610. In the case of continuous copying, the process returns to step 612 (steps 633 to 636).

FIG. 32 is an example of an optical system drive-side i wholesale program 650. When the write start timer interrupt processing routine starts, an excitation pattern is sent to the drive circuit 252 of the pulse motor 253 that drives the optical system. At the same time as the switching signal is sent out, the current value to the pulse motor 253 is switched (steps 651, 652), and after L7, a timer is set, the pulse count value is incremented, and then the pulse count check flag is set. By being set, the control routine returns to the main routine (step 653).
~655).

Furthermore, FIG. 33 shows an example of a scan start interrupt processing program 660 that is executed when a start signal for scanning start is sent from the first microcomputer 201 side and the scan start interrupt processing routine is called. When the scan start interrupt process starts, the ready state is determined, and if it is not in the ready state, a display indicating trouble is displayed, and when it is in the ready state, the excitation pattern and current are After the value is output (steps 661 to 665), the ready flag and the parnukka 1 count check flag are set (steps 666 and 667).When the pulse count flag is fully set, the process exits from this processing routine and returns to the main routine. Return.

[Effects of the Invention] As explained above, according to the present invention, since the writing timing of image data is controlled according to the rotation of the drum, the writing of image data can be performed according to the rotational position of the drum. It is possible to always match the timing. Therefore, even when recording a color image by overwriting images several times, images corresponding to each color can be recorded from the leading edge of the document, and color image recording with good registration can be achieved. Therefore, it has the feature that color image recording with improved image quality can be easily achieved.

In this case, since the start of writing is controlled based on the rotation of the drum, the registration storage controller will not deteriorate even if the load on the drum fluctuates.

Therefore, the present invention is extremely suitable for application to a color copying machine that records a desired color image by overwriting several times as described above.

[Brief explanation of drawings]

FIG. 1 is a block diagram of the entire color image processing device according to the present invention, providing a general explanation of the device, FIG. 2 is a sectional view of essential parts showing an example of a color copying machine applicable to the present invention, and FIG.
The figure is a configuration diagram of a suitable output device using this, FIG. 4 is a sectional view showing an example of a developing machine, FIG. 5 is a block diagram showing an example of an image reading device, and FIG. 6 is an image reading device. Figure 7 is an explanatory diagram of the optical scanning system, Figure 8 is a spectrum diagram of color signals, Figure 9 is a diagram used to explain color separation, and Figure 10 is a diagram of color signals. FIG. 11A is a block diagram showing an example of a color separation circuit, FIG. 11B is a block diagram showing an example of a color proximity selection circuit, and FIGS. 12 and 13 are diagrams showing color signals and 14 is a block diagram of the binarization circuit, ζ is a diagram for explaining the interpolation method, FIG. 16 is a diagram showing an example of the interface, and FIG. 17 is a block diagram of the binarization circuit. No J
Block diagrams showing peripheral circuits of the device, FIGS. 18 and 19
The figure is a block diagram of a circuit associated with the first and second microcomputers, FIG. 20 is a schematic configuration diagram showing the relationship between the image forming body and the drum index, FIG. 21 is a plan view thereof, and FIGS. FIG. 24 is a waveform diagram for explaining the color recording processing operation, FIGS. 25 to 33 are flowcharts showing an example of a control program controlled by the first and second microcomputers, and FIG. 342 is a registration relationship. FIG. 10... Image reading device 20... Color signal selection means 30... Binarization circuit 40... Interface circuit 61... Image forming body (drum) 95... Index register 96... Index detection Means 100...Output device 200.250...First and second control unit Patent applicant Konishi Roku Photo Industry Co., Ltd. Fig. 8 A [3 Fig. 17 B Yu Ω 2 Color selection rotation μ To etc. Fig. 14 so: 2 D a Ut 2 Do: ji; ... Fig. 15 B Fig. 21 Fig. 32 Fig. 33

Claims (4)

[Claims] (1) The image reading means reads color image information, photoelectrically converts this into a color image signal, further converts this into an optical signal to form an electrostatic latent image on the image forming body, and converts this into a color image signal. In a color image processing device that records color image information by developing the image, the image forming member is rotated once for each of a plurality of color signals separated from the color image signals, thereby sequentially converting the image into an electrostatic latent image. A color having a plurality of developing devices for developing the image, and a timing for starting writing on the image forming member is selected based on a drum index signal obtained in synchronization with the rotation of the image forming member. Image processing device. (2) The color image processing apparatus according to claim 1, wherein a beam scanner using a laser is used as the electrostatic latent image optical means. (3) The color image processing apparatus according to claims 1 and 2, wherein scanning of the optical means is started in synchronization with the drum index signal. (4) The color image processing apparatus according to any one of claims 1 to 3, wherein the writing timing is selected after a predetermined period of time has elapsed from the start of optical scanning.