JP4110033B2 - Image forming apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to an image forming apparatus such as a laser printer or an ink jet printer.In placeIn particular,ThatThe present invention relates to the type of recording medium (paper) and the discrimination of the surface state.
[0002]
[Prior art]
Conventionally, in an image forming apparatus such as a laser beam printer or an ink jet printer, a plurality of print modes are provided in order to obtain an optimum image corresponding to a large number of printer papers. The print mode is configured to be set by the user himself at the time of printing. For this reason, the user is required to have knowledge for discriminating the type of paper, and has the trouble of setting the paper type by himself. Furthermore, there is a problem that an optimal image cannot be obtained if the setting is wrong.
[0003]
In recent years, the difference in the amount of specular reflection light and diffuse reflection light reflected by the paper surface is detected, and the paper type is automatically discriminated to perform image formation control according to the detection result, so that an optimal image can be obtained. There is also an image forming apparatus that can be obtained. FIG. 19 shows a sectional view of a conventional printer gloss meter (see Patent Document 1 below). The gloss detector 200 has a block 210 attached to a printed circuit board 220 as usual. A light source tube 212 on the shaft 213 and a reflective tube 214 on the shaft 215 are formed in the block 210. The light source 216 is located in the light source tube 212. The optical sensor 222 is located in the reflection tube 214. At this time, the optical sensor 222 mainly reacts to the reflected spectrum light and discriminates between low gloss paper and high gloss paper.
[0004]
Also, a method has been invented for obtaining the paper roughness by capturing the surface image of the paper with a CCD area sensor and obtaining the fractal dimension. FIG. 20 shows a processing flowchart showing the basic operation of a conventional smoothness detector (see Patent Document 2 below). The surface of the recording medium is irradiated with light (step 2-1; expressed as S2-1 in the figure, the same applies to the following). Thereafter, the image detection means including the image reading means reads the shadow image formed by the reflected light of the area irradiation as a planar image, and detects the grayscale information as multivalued image data (step 2-2). That is, the irradiated light has a shadow on the reflected light due to the unevenness of the recording medium, the concave portion becomes dark and the convex portion becomes bright, and this shadow image is detected by the CCD of the image reading means. The surface roughness of the recording medium is measured and calculated by subjecting the grayscale information, which is the detected multivalued image data, to image processing by the information processing means (step 2-3). Thereafter, an image formation parameter value corresponding to the measured surface roughness is determined and controlled by the image formation control means (step 2-4). That is, in this conventional example, the surface roughness of the recording medium can be inferred by reading the density information from the CCD.
[0005]
[Patent Document 1]
JP-A-11-216938
[Patent Document 2]
Japanese Patent Laid-Open No. 11-271037
[0006]
[Problems to be solved by the invention]
However, when an imaging sensor such as an area sensor or a line sensor is used, the amount of calculation is enormous. Therefore, the circuit scale becomes large, the calculation time is prolonged, and the cost becomes expensive. In addition, when performing complex calculations, there is a problem that a large amount of memory is required, and space and cost increase.
[0007]
  The present invention has been made under such circumstances, and determines the type of recording medium.Image formation with image reading sensorIn the deviceImage reading sensorIt is an object of the present invention to reduce the circuit scale and the amount of memory.
[0008]
[Means for Solving the Problems]
  In order to solve the above-mentioned problem, in the present invention,Image formationNext (1) the equipmentOr (5)Configure as follows.
(1) An image reading sensor that receives reflected light that is irradiated onto the storage medium from a light emitting element that irradiates the surface of the recording medium and reflected by the recording medium, and reads the image on the surface of the recording medium to perform photoelectric conversion The recording element based on the two-dimensional video information having the digital value converted by the A / D conversion circuit, the A / D conversion circuit for converting the video read by the reading element into a digital value, and the A / D conversion circuit. Equipped with an image reading sensor in which an arithmetic circuit for calculating a parameter relating to the smoothing characteristic of the recording medium for discriminating the type of the medium and an output unit for outputting an arithmetic result of the arithmetic circuit are integrated into a single chip as a monolithic semiconductor device In the image forming apparatus,
An image forming unit for forming an image on the recording medium;
A discriminator for discriminating the type of the recording material;
A setting unit for setting image forming conditions of the image forming unit,
The arithmetic circuit of the video reading sensor calculates a maximum value, a minimum value, and an average value of digital values for each line in a predetermined direction of the two-dimensional video information, and calculates the calculation result for each line. Output to the determination unit,
The determination unit obtains the amount of unevenness and the number of uneven edges on the surface of the recording medium using the calculation result output from the video reading sensor, and the recording medium based on the obtained amount of unevenness and the number of uneven edges The type of
The setting unit is an image forming apparatus that sets image forming conditions according to the determined type of the recording medium.
(2) The image forming apparatus according to (1), wherein a lens for collecting reflected light from the recording medium is provided between the recording medium and the reading element.
(3) The arithmetic circuit further calculates a difference value between the maximum value and the minimum value of the digital value and the number of edges obtained by binarizing the digital value for each line using the average value. The image forming apparatus according to (1), further including an arithmetic unit that performs the operation.
(4) The image forming apparatus according to (1), wherein the output unit adds a calculation result of the calculation circuit to video information A / D-converted by the A / D conversion circuit and outputs the video information.
(5) The image forming apparatus according to (1), wherein the arithmetic circuit calculates a maximum value, a minimum value, and an average value of digital values for each line in a direction orthogonal to the predetermined direction.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to examples of a video reading apparatus and an image forming apparatus.
[0011]
【Example】
Example 1
A “video reading apparatus” that is Embodiment 1 will be described with reference to FIGS. FIG. 1 shows a schematic configuration of the image reading apparatus. The image reading apparatus includes a light source 11, a lens 12, a CMOS area sensor 13, and a diaphragm 14. The CMOS area sensor 13 may be a line sensor. The diaphragm 14 may not be provided.
[0012]
Light is emitted from the light source 11 to the recording medium 15, and a surface image of the recording medium 15 at that time is formed on the CMOS area sensor 13 through the lens 12 and the diaphragm 14.
[0013]
Next, the circuit configuration of the CMOS area sensor 13 will be described with reference to FIG. The CMOS area sensor 13 is configured as a monolithic semiconductor chip by a CMOS process.
[0014]
In the figure, reference numeral 201 denotes a CMOS sensor portion, for example, sensors for 64 × 64 pixels are arranged in an area. 202 and 203 are vertical shift registers, 204 is an output buffer, 205 is a horizontal shift register, 206 is a system clock, and 207 is a timing generator. 208 is an A / D converter, 219 is an arithmetic unit for calculating various parameters relating to smoothing characteristics for discriminating the type of the recording medium, 209 is an output interface circuit, 210 is an arithmetic result of the arithmetic unit 219, and before calculation An output terminal and a signal line for outputting video information and the like.
[0015]
Next, the operation will be described. When the Sl_select signal 213 is active, the CMOS sensor unit 201 starts to accumulate charges based on the received light. Next, when the system clock 206 is supplied, the vertical shift registers 202 and 203 sequentially select pixel columns to be read out by the timing generator 207 and sequentially set data in the output buffer 204.
[0016]
The data set in the output buffer 204 is transferred to the A / D converter 208 by the horizontal shift register 205. Pixel data digitally converted by the A / D converter 208 is transferred to the calculation unit 219. The calculation unit 219 calculates the maximum value, the minimum value, and the average value for each scanning line. The calculated result and the image data are controlled at a predetermined timing by the output interface circuit 209, and are output to the S1_out signal 210 while the S1_select signal 213 is active.
[0017]
On the other hand, the A / D conversion gain can be variably controlled by the control circuit 211 from the Sl_in signal 212. For example, if the contrast of the captured image cannot be obtained, the CPU can change the gain and always capture with the best contrast. Further, it is possible to switch between a mode in which the calculation result of the calculation unit 219 is added to the captured image data and output, and a mode in which only the calculation result is output.
[0018]
Next, a method of transferring data from the CMOS area sensor 13 to the control unit of the image forming apparatus, for example, for determining the type of recording medium and the surface state (also referred to as surface roughness) will be described.
[0019]
FIG. 3 shows the transfer timing of one pixel. Each light receiving element output is output at the falling timing of SYSCLK. Along with the falling edge of the SD_RD signal, 8 bits of each pixel are transmitted serially. At this time, the output method does not need to be serial and may be parallel.
[0020]
FIG. 4 shows the transfer timing of one line (64 pixels). The output for each line is first transmitted from the invalid pixel 401. Subsequently, 64 effective pixels 402 (for one line) are output. When the output of the 64th pixel is finished, a maximum value 403, a minimum value 404, and an average value 405 are output.
[0021]
FIG. 5 shows the transfer timing of one page (64 lines). After the invalid pixel line 501 is output, 64 effective pixel lines 502 are output.
Next, the calculation method of the maximum value, the minimum value, and the average value performed in the performance section 219 will be described with reference to FIGS.
[0022]
FIG. 6 is an image obtained by digitally processing the surface image of the recording material read by the 8 × 8 pixel CMOS sensor unit 201.
[0023]
Digital processing is performed by converting analog output output from the CMOS sensor unit 201 into 8-bit pixel data by A / D conversion.
[0024]
The recording material A of 40 is so-called rough paper in which the fibers of the paper on the surface are relatively sandwiched, the recording material B of 41 is commonly used, so-called plain paper, and the recording material C of 43 is called gloss paper. FIG. 3 is an enlarged image of the surface of a recording material in which paper fibers are sufficiently compressed. Images obtained by reading this image with the CMOS sensor unit 201 and performing digital processing are 43 to 45. Thus, the image on the surface varies depending on the type of recording material.
[0025]
This is a phenomenon that occurs mainly because the fiber state on the paper surface is different. In other words, when the fiber state of the paper is standing, the light irradiated obliquely onto the paper surface can be shaded by the fiber, and when the fiber is in a state of shadow, it cannot be shaded. Such a phenomenon results in 43 to 45 images.
[0026]
Next, a method for detecting the unevenness on the surface of the recording material will be described with reference to FIG. In FIG. 7, reference numeral 50 denotes an image obtained by digitally processing the image of the surface of the recording material.
[0027]
The analog output output from the CMOS sensor unit 201 is A / D converted to 8-bit pixel data, and 8-bit data is determined in proportion to the brightness of the image. At that time, 51 is the darkest part in the first line of 8 × 8 pixels, and in the example shown in the figure, “80” h, 52 is the brightest part in the first line of 8 × 8 pixels. In the example shown in the figure, it is “10” h. The values after A / D conversion are sequentially sent to the calculation unit 219 in the scanning direction.
[0028]
FIG. 8 shows a block diagram of the calculation unit 219. The calculation unit 219 includes a maximum value storage unit 2204 that stores a maximum value, a minimum value storage unit 2205 that stores a minimum value, and an average value storage unit 2206 that stores an average value. Written to the area. Subsequently, the next data is sent to the respective comparison units 2201, 2202, 2203.
[0029]
For example, first, data is sent to the maximum value comparison unit 2201 and compared with the data in the maximum value storage unit 2204. If the data is larger than the maximum value, the area for storing the maximum value is rewritten. The data sent to the maximum value comparison unit 2201 is subsequently sent to the minimum value comparison unit 2202, and similarly, if it is smaller than the minimum value, the area for storing the minimum value is rewritten. Thereafter, the data is sent to the average value addition unit 2203 and added to the value in the average value storage unit 2206. For example, in the case of the first line, 51 “80” h is written in the maximum value storage unit 2204, and 52 “10” h is written in the minimum value storage unit 2205. When one line is completed, the total value of the output data for one line is written in the average value storage unit 2203. Therefore, the value is divided by 1/8 and output to the outside of the CMOS area sensor as an average value. The At this time, it is possible to divide by 1/8 for each pixel and write it in the average value storage unit 2206.
[0030]
Thereafter, the calculation result is converted into serial data by the serial signal generation unit 2207 and transmitted to the outside of the chip. Thereby, the control unit outside the sensor chip can calculate the size of the surface irregularities by calculating the difference between the transmitted maximum value and minimum value, and can determine the type of the recording material.
[0031]
Thus, by providing a mechanism for calculating the maximum value, minimum value, and average value inside the sensor chip, it is not necessary to have a large logic circuit outside the CMOS area sensor. Therefore, there is an advantage that the sensor can be used even when the entire system does not have a logic circuit. That is, by providing the logic circuit inside the sensor and making it into one chip, it is possible to reduce the size and reduce the cost.
[0032]
Further, when the mode for sending only the calculation result is selected, the transfer speed can be increased.
[0033]
The control unit of the image forming apparatus determines the type and surface state of the recording medium by determining the type and surface state of the recording medium based on the size and width of the unevenness on the surface and controlling the image forming conditions. Regardless, good image formation can be performed.
[0034]
As described above, according to the present embodiment, in the video reading apparatus that determines the type of recording medium and the like, the circuit scale can be reduced and the memory can be reduced. Further, since the CMOS area sensor itself is provided with a mechanism for calculating the maximum value, the minimum value, and the average value, it is possible to reduce the amount of communication to the control unit of the image forming apparatus, and further reduce the calculation circuit of the control unit. be able to. As a result, the amount of calculation in the control unit is reduced, and the speed, size, and cost can be reduced.
[0035]
(Example 2)
A “video reading apparatus” according to the second embodiment will be described with reference to FIGS. 9, 10, and 11. Since the basic configuration is the same as that of the first embodiment, the description of the first embodiment is used for portions having the same configuration as the first embodiment, and only portions having a configuration different from that of the first embodiment will be described.
[0036]
If the state of FIG. 9 is a normal state, FIG. 10 shows a case where the image is dark as a whole because the amount of light or the accumulation time is insufficient. In such a case, the portion 91 that is too dark has fallen below a predetermined lower limit value. When there is a value below the lower limit, it is possible to detect that the image is too dark and an accurate amount of contrast cannot be obtained by providing a mechanism for raising the underflow bit.
[0037]
On the other hand, FIG. 11 shows a case where the image is too bright as a whole because the light amount or the accumulation time is too much compared to the normal state of FIG. In such a case, the too bright portion 101 has exceeded a predetermined upper limit value. When there is a value exceeding the upper limit, it is possible to detect that the image is too bright and an accurate contrast cannot be obtained by providing a mechanism for setting an overflow bit.
[0038]
When re-shooting, if the underflow bit is set, the light amount or the accumulation time may be increased, and if the overflow bit is set, the light amount or the accumulation time may be decreased. You can also decide whether to drop or raise.
[0039]
FIG. 5 shows the transfer timing of one page (64 lines). After outputting the invalid pixel line, 64 valid pixel lines 502 are outputted, and after the 64th line is outputted, an overflow bit and an underflow bit are outputted in the overflow / underflow bit area 503.
[0040]
As described above, according to the present embodiment, it is possible to immediately determine from the signal from the video reading apparatus whether or not the light amount at the time of shooting is appropriate and whether the light amount should be increased or decreased at the time of re-shooting. The configuration of the control unit of the image forming apparatus (not shown) can be simplified.
[0041]
(Example 3)
A “video reading apparatus” that is Embodiment 3 will be described with reference to FIGS. Since the basic configuration is the same as that of the first embodiment, the description of the first embodiment is used for portions having the same configuration as the first embodiment, and only portions having a configuration different from that of the first embodiment will be described.
[0042]
FIG. 12 shows the case where the output overflows only one pixel and outputs the upper limit value due to the defective pixel 111. Even when the amount of light is sufficiently reduced, if there is an overflowing pixel, it can be determined that there is a defective pixel.
[0043]
FIG. 13 shows a case where the output of only one pixel underflows due to the defective pixel 121 to indicate the lower limit value. If there is a pixel underflowing even when the amount of light is sufficiently increased, it is determined that there is a defective pixel.
[0044]
As described above, according to the present embodiment, it is possible to determine whether or not there is a defective pixel with a small amount of calculation by calculating the overflow bit and the underflow bit in the CMOS area sensor.
[0045]
Example 4
With reference to FIG. 4, a “video reading apparatus” that is Embodiment 4 will be described. Since the basic configuration is the same as that of the first embodiment, the description of the first embodiment is used for portions having the same configuration as the first embodiment, and only portions having a configuration different from that of the first embodiment will be described.
[0046]
In the first embodiment, the CMOS area sensor 13 is provided with computing means for computing the number of edges when binarized using the maximum value and the minimum value of the sensor, or the difference between them, and the average value as a threshold value. The unit 401 and the effective pixel unit 402 do not transmit, and only the calculated data is transmitted to the control unit, so that the amount of communication to the control unit can be greatly reduced.
[0047]
Therefore, it is possible to increase the speed, size, and cost of a control unit of an image forming apparatus (not shown).
[0048]
(Example 5)
A “video reading apparatus” that is Embodiment 5 will be described with reference to FIGS. Since the basic configuration is the same as that of the first embodiment, the description of the first embodiment is used for portions having the same configuration as the first embodiment, and only portions having a configuration different from that of the first embodiment will be described.
[0049]
FIG. 14 shows a surface image in the case where the paper fiber has directionality. In FIG. 14, the difference between the maximum value and the minimum value in the predetermined region 132 that is long in the same direction as the fiber direction and the difference between the maximum value and the minimum value in the predetermined region 131 that is long in the direction perpendicular to the fiber direction. In the case of viewing, the calculation result is larger when viewed in the direction perpendicular to the fiber direction. In addition, the number of edges in the case of binarization in FIG. 15 is calculated in a predetermined region 141 that is longer in the direction perpendicular to the fiber direction than in the case where the predetermined region 142 is longer in the same direction as the fiber direction. In this case, the number of edges becomes larger. By giving the area to be calculated the direction of the vertical direction and the horizontal direction and performing the averaging, the calculation result can be averaged even when the fiber orientation is measured vertically or horizontally. The structure which is not influenced by the directionality of a fiber can be taken.
[0050]
That is, setting means for arbitrarily setting areas for calculating the maximum value, the minimum value, and the average value is provided in the image reading apparatus, and the area can be changed as necessary to suppress variations in detection results. By doing so, it is possible to measure the smoothness of the paper even when a paper of a different type is used.
[0051]
(Example 6)
FIG. 16 is a cross-sectional view illustrating a schematic configuration of an “image forming apparatus” according to the sixth embodiment. Since the basic configuration of the video reading apparatus is the same as that of the first embodiment, the description of the first embodiment is cited, and only the portions that are different from the first embodiment will be described.
[0052]
In the figure, 1501 is an image forming apparatus, 1502 is a paper cassette, 1503 is a paper feed roller, 1504 is a transfer belt drive roller, 1505 is a transfer belt, 1506 to 1509 are yellow, magenta, cyan and black photosensitive drums, and 1510 to 1513 are Transfer rollers 1514 to 1517 are yellow, magenta, cyan, and black cartridges, 1518 to 1521 are yellow, magenta, cyan, and black optical units, and 1522 is a fixing unit.
[0053]
The image forming apparatus transfers an image of yellow, magenta, cyan, and black on a recording sheet by using an electrophotographic process, and heat-fixes the toner image by a fixing unit 1522 based on temperature control.
[0054]
Each color optical unit is configured to form a latent image by exposing and scanning the surface of each photosensitive drum with a laser beam, and a series of these image forming operations is performed from a predetermined position on the conveyed recording paper. Scan control is performed in synchronization with the transfer.
[0055]
Further, the image forming apparatus includes a paper feed motor that feeds and conveys recording paper as a recording material, a transfer belt drive motor that drives a transfer belt drive roller, and a photosensitive drum that drives each color photosensitive drum and transfer roller. A drum driving motor and a fixing driving motor for driving the fixing roller are provided.
[0056]
Reference numeral 1523 denotes an image reading apparatus (see Examples 1 to 5), which irradiates light onto the surface of the recording paper to be fed and conveyed, condenses the reflected light to form an image, and identifies the recording material. Detect area image.
[0057]
A control CPU (not shown) provided in the image forming apparatus fuses and fixes the toner image on the recording paper by applying a desired amount of heat to the recording paper by the fixing unit 1522.
[0058]
Next, the operation of the control CPU will be described with reference to FIG. FIG. 17 is a diagram illustrating the configuration of each unit controlled by the control CPU.
[0059]
In the figure, 1610 is a CPU, 13 is a CMOS area sensor, 1612 to 1615 are provided with polygon mirrors, motors, and lasers, an optical unit for scanning the surface of the photosensitive drum to draw a desired latent image, and 1616 is a recording unit. A paper feed motor for conveying the material, 1617 is a paper feed solenoid used to start driving the paper feed roller for feeding the recording material, and a paper for detecting whether or not the 1618 recording material is set at a predetermined position. Presence sensor 1619 is a high-voltage power source that controls primary charging, development, primary transfer, and secondary transfer bias necessary for the electrophotographic process, 1620 is a drum drive motor that drives the photosensitive drum and the transfer roller, and 1621 is a transfer belt and A belt driving motor 1622 for driving the rollers of the fixing unit is a fixing unit and a low-voltage power supply unit. Monitoring the temperature by a thermistor (not shown) by CPU 1610, control is performed to keep the fusing temperature constant.
[0060]
Reference numeral 1623 denotes an ASIC, which controls the speed of the motor in the CMOS area sensor 13 and the optical units 1612 to 1615 and the speed of the paper feed motor 1616 based on an instruction from the control CPU 1610.
[0061]
The speed control of the motor is performed by detecting a tack signal from a motor (not shown) and outputting an acceleration or deceleration signal to the motor so that the interval between the tack signals becomes a predetermined time. For this reason, if the control circuit is configured by a hardware circuit of the ASIC 1623, there is an advantage that the control load of the CPU 1610 can be reduced.
[0062]
When receiving a print command in response to an instruction from a host computer (not shown), the control CPU 1610 determines the presence / absence of a recording material by a paper presence sensor 1618. If there is paper, the control CPU 1610 feeds a paper feed motor 1616, drum drive motor 1620, belt drive. The motor 1621 is driven and the paper feed solenoid 1617 is driven to convey the recording material to a predetermined position.
[0063]
When the recording material is conveyed to the position of the CMOS area sensor 13, the control CPU 1610 instructs the ASIC 1623 to image the CMOS area sensor 13, and the CMOS area sensor 13 captures a surface image of the recording material.
[0064]
At this time, the ASIC 1623 activates Sl_select, outputs SYSCLK of a predetermined pulse at a predetermined timing, and captures imaging data output from the CMOS sensor unit 201 via Sl_out.
[0065]
On the other hand, the gain setting of the CMOS area sensor 13 is performed by setting a value determined in advance by the control CPU 1610 to a register in the ASIC 1623 so that the ASIC 1623 activates Sl_select and then outputs SYSCLK of a predetermined pulse at a predetermined timing. The gain is set for the CMOS area sensor 13 via Sl_in.
[0066]
The ASIC 1623 receives the maximum value and the minimum value output from the CMOS area sensor chip 13 for each scanning line. For example, in the case of FIG. 7, after reading one line, the difference between the two values, '80 'h-'10'h =' 70'h is calculated and stored in the region for storing the unevenness calculation result value.
[0067]
For example, in FIG. 7, the difference between the maximum contrast value and the minimum contrast value in the first line is' 70'h.
[0068]
Similarly, 53 is the value of the darkest part of the second line, '80'h, 54 is the value of the brightest part of the second line,' 20'b, and the difference is' 80'h-'20. 'h =' 60'h is obtained, and this value ('60'h) is added to the region for storing the unevenness calculation result.
[0069]
55 is the value of the darkest part of the eighth line, '80'h, 56 is the value of the brightest part of the eighth line,' 10'h, and the difference is' 80'h-'10'h = '70'h.
[0070]
In this way, a value obtained by adding the difference between the maximum value and the minimum value for all lines for each line is defined as the unevenness calculation result value on the surface of the recording material.
[0071]
Next, a method in which the ASIC 1632 detects the uneven edge amount on the surface of the recording material will be described with reference to FIG.
[0072]
Reference numeral 50 denotes an image obtained by digitally processing the surface of the recording material. 60 is a result of binarizing an 8 × 8 image picked up at the next sampling timing with the total value of the average values output for each line as a threshold in advance at the previous sampling timing of the CMOS sensor unit 201. FIG. At this time, a similar thumbtack can be obtained even if the average value of the previous line is read for each line and the value is used as the dark value.
[0073]
61 is the number of edges in the first line as a result of binarization, and in this example is' 05'h. 62 is the number of edges in the second line, which is' 03'h in this example.
[0074]
Similarly, 63 is the number of edges in the eighth line, which is' 03'h in this example.
[0075]
A value obtained by counting the number of edges for each line and adding all the lines is defined as a calculation result value of the uneven edge amount on the recording surface.
[0076]
As described above, the ASIC 1623 writes the two values of the unevenness calculation result on the surface of the recording material and the number of uneven edges on the surface of the recording material into the internal register.
[0077]
The CPU 1610 reads the register in the ASIC 1623, determines the type of the fed recording material, and variably controls the developing bias condition of the high voltage power supply 1619 according to the result.
[0078]
For example, in the case of so-called rough paper where the surface fibers of the recording material are rough, control is performed to prevent toner scattering by lowering the developing bias than plain paper and suppressing the amount of toner adhering to the surface of the recording material. This is because the amount of toner adhering to the surface of the recording material is large especially in the case of rough paper, so that the problem that the image quality deteriorates due to the scattering of the toner due to the paper fibers is solved.
[0079]
Further, the CPU 1610 discriminates the type of the fed recording material, and variably controls the temperature condition of the fixing unit 1622 according to the result. This is particularly effective in the case of OHT, when the fixing property of the toner adhering to the surface of the recording material is poor, the OHT permeability is deteriorated.
[0080]
Further, the CPU 1610 determines the type of the fed recording material, and variably controls the recording material conveyance speed according to the result. The variable control of the conveyance speed is realized by the CPU 1610 setting the speed control register value of the ASIC 1623 that controls the speed control. In particular, in the case of OHT or gloss paper, it is possible to improve the fixability of the toner adhering to the surface of the recording material and improve the gloss to improve the image quality.
[0081]
As described above, in this embodiment, the difference between the maximum value and the minimum value is calculated from the surface image of the recording material imaged by the CMOS area sensor by the ASIC hardware circuit as described in Embodiment 1, and the image is By binarizing and counting the number of edges, the CPU can improve the image quality by variably controlling the developing conditions, the control temperature conditions of the fixing unit, the conveyance speed of the recording material, and the like.
[0107]
【The invention's effect】
As described above, according to the present invention, it is possible to provide an image reading apparatus that is suitable for determining the type and surface state of a recording medium and has a small circuit scale and a small memory.
[Brief description of the drawings]
FIG. 1 is a diagram showing a schematic configuration of a first embodiment.
FIG. 2 is a block diagram showing the configuration of a CMOS area sensor
FIG. 3 is a diagram showing transfer timing of one pixel (8 bits)
FIG. 4 is a diagram showing transfer timing of one line (64 pixels)
FIG. 5 is a diagram showing transfer timing of one page (64 lines)
FIG. 6 is an explanatory diagram of the first embodiment.
7 is an explanatory diagram of Example 1. FIG.
FIG. 8 is a block diagram showing a configuration of a calculation unit
FIG. 9 is an explanatory diagram of the second embodiment.
FIG. 10 is an explanatory diagram of the second embodiment.
FIG. 11 is an explanatory diagram of the second embodiment.
FIG. 12 is an explanatory diagram of Example 3
FIG. 13 is an explanatory diagram of the third embodiment.
FIG. 14 is an explanatory diagram of the fifth embodiment.
FIG. 15 is an explanatory diagram of the fifth embodiment.
FIG. 16 is a sectional view showing a schematic configuration of Example 6;
FIG. 17 is a diagram showing each unit controlled by a CPU.
18 is an explanatory diagram of Example 6. FIG.
FIG. 19 is a sectional view of a printer gloss meter disclosed in Japanese Patent Application Laid-Open No. 11-216938.
FIG. 20 is a flowchart showing the basic operation of the smoothness detector disclosed in Japanese Patent Laid-Open No. 11-271037.
[Explanation of symbols]
13 CMOS area sensor
15 Recording media
201 CMOS sensor
208 A / D converter
209 Output interface circuit
219 Calculation unit

Claims (5)

Emitted from the light emitting element for irradiating the surface of the recording medium to the storage medium, a video reading sensor for receiving the reflected light reflected by said recording medium, reading photoelectrically converted by reading the image of the surface of the record medium element and the a / D conversion circuit for converting a digital value movies image read by the reading device, said recording medium based on the two-dimensional image information having a digital value converted by the a / D converter circuit types and arithmetic circuit for calculating a parameter related to the smooth characteristics of the recording medium to determine the video reading sensor and an output unit is a single chip as monolithic semiconductors device for outputting an operation result of the arithmetic circuit In the installed image forming apparatus,
An image forming unit for forming an image on the recording medium;
A discriminator for discriminating the type of the recording material;
A setting unit for setting image forming conditions of the image forming unit,
The arithmetic circuit of the video reading sensor calculates a maximum value, a minimum value, and an average value of digital values for each line in a predetermined direction of the two-dimensional video information, and calculates the calculation result for each line. Output to the determination unit,
The determination unit obtains the amount of unevenness and the number of uneven edges on the surface of the recording medium using the calculation result output from the video reading sensor, and the recording medium based on the obtained amount of unevenness and the number of uneven edges The type of
The image forming apparatus , wherein the setting unit sets image forming conditions according to the determined type of the recording medium . Before SL lens for condensing the reflected light from the recording medium, the image forming apparatus according to claim 1, characterized in that provided between the recording medium and the reading device.   The arithmetic circuit further calculates a difference value between the maximum value and the minimum value of the digital value and the number of edges obtained by binarizing the digital value for each line using the average value. The image forming apparatus according to claim 1, further comprising: The image forming apparatus according to claim 1, wherein the output unit adds the calculation result of the calculation circuit to the video information that has been A / D converted by the A / D conversion circuit, and outputs the image information.   The image forming apparatus according to claim 1, wherein the arithmetic circuit calculates a maximum value, a minimum value, and an average value of digital values for each line in a direction orthogonal to the predetermined direction.

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