JP2007124100A - Photoelectric conversion apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photoelectric conversion apparatus capable of eliminating an image noise out of an original without depending on an image processing circuit by executing original scanning while improving such a problem at the time of reading. <P>SOLUTION: The apparatus has a plurality of photoelectric conversion means; a plurality of optical signal holding means for holding each of the optical signals of the plurality of photoelectric conversion means; an optical signal output line for outputting optical signals from the optical signal holding means; a resetting means for resetting the optical signal output line to a fixed potential; a driving pulse control means; an electric charge transfer means for reading the signals of the photoelectric conversion means via the optical signal output means; and a comparator means for comparing the electric charge transfer signal level with a reference value for each pixel, and substituting the level by a predetermined luminous level. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a photoelectric conversion device, for example, a one-dimensional or two-dimensional photoelectric conversion device that reads an image such as a facsimile, an image scanner, a digital copying machine, and the like, and particularly, is unnecessary in image formation (image noise) when scanning a document. The present invention relates to a photoelectric conversion device that outputs a pixel signal level in a region outside a document with a specific luminance density level (white level).

  Conventionally, as an image reading system for a facsimile, an image scanner, a digital copying machine, etc., a reading system using a CCD of a reduction optical system has been used. The development of contact image sensors (CIS) is also remarkable.

  However, in an apparatus (hereinafter referred to as an image forming apparatus) that uses the above-described photoelectric conversion device such as a CCD or CIS as a scanning object (subject, original) reading means, it is really out of all image signals read by the CCD or CIS. The storage means for taking out only the image of the necessary scanning object and the dedicated image processing means are required, and the image processing circuit is enlarged.

  In addition, there are factors that impair the real-time property of image processing, such as the need to take measures such as line memory that interpolates the data delay for the processing time required for the image processing, thereby realizing simplification of the image processing circuit. This is most important from the viewpoint of image processing responsiveness and apparatus cost reduction.

  In the background described above, in an apparatus (image forming apparatus) using a photoelectric conversion device such as a CCD or CIS as a scanning object (subject, original) reading means, an output signal of the photoelectric conversion device is subjected to image processing in units of main scanning. Therefore, an image of [scan object + out of scan object] is read, and the area of the scan object is read from the read image as a detection result of the document (scan object) size detection unit of the image forming apparatus. Trimming (extraction of the document area) is performed, and an image forming process is executed for an area corresponding to the size of the scanning object.

  However, the conventional image forming apparatus has a problem that an image other than the original (scanning object) is formed in the following points.

  1) When reading an original (scanning object) other than the standard size, an output (recording) paper that is one size larger than the original size is selected, and the original plate of the pressure plate or the original feeding (conveying) device is pressed against the original area. The dirt on the members forms an image together. Further, when the pressure plate or the document feeding (conveying) device is in an open (open) state, the outside area of the document is completely black.

  2) In a state where the document is set obliquely, even if it is a standard-sized document, a region where the document is not set is generated in the assumed document region, and the platen and the document pressing member of the document feeding (conveying) device are dirty. Will be imaged together. Further, when the pressure plate or the document feeding (conveying) device is in an open (open) state, the outside area of the document is completely black.

In order to solve these problems, a latent image is formed in an area outside the original according to the original size as a device for improving toner adhesion caused by forming a latent image outside the original area due to the positional deviation of the original. As an image forming device that forms a white image outside the original area when there is no image forming device or when the original cover is opened during copying, the out-of-original signal component erases the signal component outside the original according to the detection result of the original size. An image forming apparatus having a means has been proposed.
Japanese Patent Publication No. 6-085099 JP-A-8-046786 Japanese Patent Laid-Open No. 10-098607

  However, the above-described conventional example performs processing on a document reading signal as processing for image formation, and does not eliminate the above-described problem at the time of document reading. For this reason, image processing means for the area outside the document is required.

  The present invention has been made in view of the above problems, and by scanning an original while improving such a problem at the time of reading an original, image noise in an area outside the original is removed without relying on an image processing circuit. An object of the present invention is to provide a photoelectric conversion device capable of performing the above.

  To achieve the above object, the present invention provides a plurality of photoelectric conversion means, a plurality of optical signal holding means for holding optical signals of the plurality of photoelectric conversion means, and an optical signal output from the optical signal holding means. An optical signal output line; a reset means for resetting the optical signal output line to a fixed potential; a drive pulse control means; a charge transfer means for reading out a signal of the photoelectric conversion means for each pixel via the optical signal output line; The charge transfer signal level is compared with a reference value for each pixel, and has a comparing means for replacing the level with a predetermined luminance level.

The present invention also provides a plurality of photoelectric conversion means, a plurality of optical signal holding means for holding the optical signals of the plurality of photoelectric conversion means, and an optical signal output line for outputting an optical signal from the optical signal holding means. A reset means for resetting the optical signal output line to a fixed potential; a drive pulse control means for controlling the drive mode of the photoelectric conversion means; and a signal from the photoelectric conversion means for each pixel via the optical signal output line. In a photoelectric conversion device having a charge transfer means for reading,
A special operation mode of the photoelectric conversion means controlled by the drive pulse control means, a comparator means for comparing the signal level in the special operation mode state with a reference value for each pixel, and a comparison result in the special operation mode state. Accordingly, there is provided means for setting an effective area of the photoelectric conversion means and means for replacing an output outside the effective area with a predetermined luminance level determined in advance.

Furthermore, the present invention provides a plurality of photoelectric conversion means, a plurality of optical signal holding means for holding optical signals of the plurality of photoelectric conversion means, and an optical signal output line for outputting an optical signal from the optical signal holding means, A reset means for resetting the optical signal output line to a fixed potential; a drive pulse control means for controlling the drive mode of the photoelectric conversion means; and a signal from the photoelectric conversion means for each pixel via the optical signal output line. In a photoelectric conversion device having a charge transfer means for reading,
Based on input information via the external interface of the photoelectric conversion device, the photoelectric conversion device includes an effective area setting unit, and a unit that replaces an output outside the effective area with a predetermined luminance level.

  According to the present invention, it is possible to provide a photoelectric conversion apparatus capable of performing image noise removal on an area outside a document that could not be processed during scanning in the conventional configuration in real time.

  By providing the photoelectric conversion device with a configuration for replacing the signal level outside the document area with a predetermined signal level, it is possible to suppress image noise in the area outside the document without depending on the image processing circuit.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

<Embodiment 1>
1 is a configuration diagram of a photoelectric conversion apparatus according to Embodiment 1 of the present invention, FIG. 2 is a block diagram of an image forming apparatus equipped with the photoelectric conversion apparatus of the present invention, and FIG. 3 is a diagram of a photoelectric conversion apparatus according to an embodiment of the present invention. It is a timing chart.

  The configuration and operation of the apparatus will be described below.

In the timing chart of FIG. 3, the start pulse SP301 (103) is supplied to the shift register SR129 in synchronization with the clock CLK (102) shown at 302, the reset pulse φCR303 (106) is set high, and the MOS transistors 123 and 124 are turned on. Then, the signal holding capacitors C _TS 121 and C _TN 122 are reset, and then the light quantity 153 by the image is accumulated in the base of the photoelectric conversion element 101. After the accumulation is completed, the transfer pulse φTS 306 (107) is transferred as high. The MOS transistor 119 is turned on, an optical signal including noise is read (Signal Read out), and transferred to the optical signal holding capacitor C _TS 121.

Subsequently, the reset pulse φBRS 304 (109) is set to low to turn on the MOS transistor 111, and then the reset pulse φE _RS 305 (110) is set to high to perform the reset operation of the sensor 101 of the photoelectric conversion element. The signal component when there is no optical signal of the photoelectric conversion element 101 is set as a noise component, the reset pulse φT _N 307 (108) is set high, the noise transfer MOS transistor 120 is turned on, and the noise signal is transferred to the noise signal holding capacitor CTN122. Again, the reset pulse φB _RS 304 (109) is set to low, the reset pulse φE _RS 305 (110) is set to high, and the reset MOS transistor 112 is turned on, so that the sensor is reset and the next storage operation is started.

  In the present embodiment, the operation of reading one photoelectric conversion element has been described. However, in the case of a one-line photoelectric conversion element, circuit elements similar to those in FIG. 1 corresponding to each photoelectric conversion element are the same. In operation, the optical signal charge and noise signal charge of the one-line sensor are transferred to each holding capacitor.

On the other hand, during the accumulation operation, scanning is started by the input pulses φ1 (308, 104) and φ2 (309, 105) whose phase is inverted by the shift register SR129. First, the optical signal common output line 130 and the noise signal common output line 131 are first reset by turning on the reset MOSs 134 and 135 by setting the reset pulse φC _HR 136 to high, and then the signal holding capacitors C _TS 121 and C _TN 122. The scanning MOS transistors 125 and 126 are turned on by setting the scanning pulse 152 from the shift register SR129 to high in the capacity division of each common output line and the capacitance, and are output to the common output lines 130 and 131.

Here, C _HS 128 and C _HN 127 are capacities of the respective common output lines. Hereinafter, the optical signal common output line is defined as C _HS 128 and the noise signal common output line is defined as C _HN 127. The signals output to the common output lines 130 and 131 are amplified by the preamplifiers 139 and 138, respectively, the difference between the optical signal component and the noise signal component is obtained by the differential amplifier 140, and the clamp circuit 141 increases the clamp pulse φC _L 142. When the clamp MOS 144 is turned on, the operation signal level and the signal level clamped at the V _REF 143 potential are alternately repeated as the potential at the output terminal of the capacitor 145. The difference signal clamped for each pixel is amplified by the amplifier 146 and output as an image signal.

Thereafter, the capacitances CHS128 and C _HN 127 of the common output line are set again, the reset pulse φC _HR 136 is set to high, the reset MOS transistors 134 and 135 are turned on, and the common output lines 130 and 131 are reset to the reference potential VC _HR 137. The data of the next bit signal holding capacitors C _TS 121 and C _TN 122 is read.

Next, the balance adjustment control of the capacitances C _HS and C _HN of the common output line will be described with reference to FIG. FIG. 4 is an enlarged timing chart of FIG. 3-310.

In synchronization with the clock signal CLK 401, pulses φ 1 (402) and φ 2 (403) are input to the shift register SR 29, and a reset pulse φC _HR 404 for resetting the common output lines 130 and 131 is output. Thereby, the capacitances C _HS and C _HN of the common output line are reset.

However, since the capacitances C _HS and C _HN of the common output lines actually have some variation, the switch MOS 132 that connects the common output lines 130 and 131 is turned on by the switch pulse φSW 405 to eliminate the variation, The potentials of the common output lines 130 and 131 are adjusted. First, this operation is repeated at a period T, and all bit signals are output. The output signals are input to the differential amplifier 140 via the voltage follower preamplifiers 139 and 138, respectively, and a photoelectric conversion element output for each pixel is obtained.

  The operation state of the photoelectric conversion device in the timing chart of FIG. 3 is as follows.

A: Reset period of the signal holding capacitors C _TS and C _TN B: Signal + noise signal readout period C: Reset period of the photoelectric conversion element D: Noise signal readout period E: Reset period of the photoelectric conversion element F: Document scanning and data output G: Accumulation time The configuration described above is the basic operation of photoelectric conversion of the photoelectric conversion device.

  In FIG. 1, the block configuration of the photoelectric conversion device is divided into a photoelectric conversion element block (Pixel Block) 151, charge storage means (Line Memory) 149, an output circuit (Output Line) 148, and a shift register (Shift Register) 129. However, the selector (SELECTOR) indicated by 160 can selectively switch the drive signal generated in synchronization with the external CLK158 by the pulse generator (PULSE GENERATOR) 155 by supplying the drive signal of the photoelectric conversion device from the outside. Device.

  In contrast to the general photoelectric conversion device described above, the present case realizes data processing different from that of the conventional photoelectric conversion device by providing the photoelectric conversion device with the following functions.

  Reference numerals 156 and 157 denote communication lines of the photoelectric conversion device. For example, reference numeral 157 denotes a reference value signal supplied as a comparison level of the comparator 154 via mode data for setting an operation mode from the outside to the photoelectric conversion device, or an approximate pulse generator (PULSE GENERATOR) 155. This is a supply line or a select control signal supply line capable of controlling the selector 161 for each pixel.

  Further, the signal of the photoelectric conversion device is guided to the comparator 154 through the buffer 146 by the operation mode setting data, and the original size detection operation (original area signal generation) is performed, and the outside area of the original is based on the approximate detection result. Is replaced with a predetermined level (white level), or the output of the approximate photoelectric conversion means led to the comparator 154 via the buffer 146 is compared with the approximate comparison level for each pixel, and the comparison level By replacing the area beyond the original area with a predetermined level (white level), it is possible to output an output signal of the photoelectric conversion device from 147.

  The predetermined level described here refers to a VTOP signal level (white level) that determines an input range of an A / D converter that is generally used as a means for converting an analog output of a sensor into a digital signal. Yes.

  Also, 156 outputs data from the photoelectric conversion device to the outside. For example, in the read data, an effective area signal (ENABLE-signal) corresponding to the document width or the above area signal is converted into pixel information. The pixel information from the x pixel to the y pixel can be output.

  As described above, the general outline of the photoelectric conversion device has been described, but the photoelectric conversion device is not normally used alone. Therefore, how the photoelectric conversion device is used in an actual apparatus (image forming apparatus) will be described below.

  The block diagram shown in FIG. 2 shows an example of an image forming apparatus.

  The image forming apparatus includes a reader unit 201, a printer unit 220, a document feeding device 215, a system controller 217, and an operation unit 218. The operation flow based on the block diagram will be described. When a document is set on the document feeder 215 by an operator (not shown), the document is detected by the document detection means 222 (not shown), and the ADF controller 216 and the reader controller are detected. Information is exchanged between 202.

  The document set information is further transmitted to the system controller 217 via the reader interface unit 214, and some document set information (message) is displayed on the display unit 219 on the operation unit 218 to prompt the user to set copy conditions. Normally, the operator sets the number of copies, document conditions (single-sided, double-sided, etc.) and the like from the operation unit 218 as the next control.

  When the setting is completed and the operator presses the copy button 223, a document conveyance start request signal is sent to the ADF controller 216 via the system controller 217, the reader interface unit 214, and the reader controller 202. At the same time, the reader controller 202 controls the optical motor 213 via the motor driver 212 and moves a document illumination unit (not shown) including a document illumination light source 204 composed of a xenon tube or LED to a document reading standby position. Control.

  Further, the reader controller 202 transmits a control signal 210 to the photoelectric conversion device 205, and controls the drive of the pulse generator unit 207 inside the photoelectric conversion device 205 (or an external pulse generator) and the pulse via 211. The drive pulse from the generator unit 207 is supplied to the CMOS-SENSOR 206, and the drive control of the CMOS-SENSOR 206 is started. Usually, when starting the drive control of the device, it is necessary to wait for the rise time of the device. After a predetermined waiting time, the lighting control of the light source 204 is performed by the inverter 203, and the shading correction using the white reference plate 225 is performed. Done.

  When the preparation for reading the original is completed, the reader controller 202 controls the optical motor 213 via the optical motor driver 212, and sets the original illumination light source 204 composed of a xenon tube or LED or the like at an original reading position (not shown). The original illuminating means (not shown) is moved, the ADF controller 216 is requested to convey the original, and the original conveyance control is started by the original conveying motor 224. The original is controlled at a constant speed relative to the photoelectric conversion device 205. Is conveyed and image data is read. The read image signal can output an option signal 209 together with the video signal 208. For example, by sending a document area (width, position, etc.) signal to the controller 202, it is effective in image processing (not shown). It becomes possible to clarify the area (document area). Here, the video signal 208 is a signal obtained by replacing the area outside the document with a VTOP (white) 227 level that is a white reference level of the A / D converter 226, and the option signal 209 has a meaning of a document position signal.

  The original image read along the above flow is subjected to predetermined image processing by the reader controller 202 and then sent to the system controller 217 via the reader interface unit 214, and printed out by the printer contour roller 221 of the printer unit 220. Control is performed and a printed output can be obtained.

  Next, the contents of problems in the conventional image forming apparatus will be described with reference to FIG.

  FIGS. 5G and 5H show a pressure plate model and an ADF model, respectively. The detailed configuration of the model will be described below.

  First, the configuration of FIG. 5G is as follows. Reference numeral 501 denotes a leader portion. Reference numeral 502 denotes a pressure plate for pressing the original, and 503 is a white sheet having elasticity, and a function of pressing the original 504 against the original platen glass 505 and image noise suppression by reading the area outside the original of the irregular original white. It has a function.

  Reference numeral 507 denotes an original illuminating unit, which is used for an original size detecting operation in synchronization with the closing operation 506 of the pressure plate 502 together with the CCD type sensor 529 and the reflective original size detecting unit indicated by 513. Incidentally, reference numerals 511 and 512 denote document widths. Similarly, FIG. 5H is an ADF model having an ADF (auto document feeder) 527 and a document conveying belt 528, and a model in which a reflection document size detecting means 514 is mounted in the main scanning direction on the reader side. Show.

  The flowchart of FIG. 5 (i) is a flow chart of the simplest operator operation. When the original 504 is set on the original platen glass 505 and the original pressure plate 502 is closed, the unillustrated pressure plate SW is turned ON 517 via the flows 515 and 516. The time from when the pressure plate 502 starts to close until the pressure plate SW (not shown) is turned on has no detection means, and is in a standby state. When the pressure plate SW is turned ON at 517, a document size detection operation 518 is started. When the document size is confirmed 519, the result is displayed 520 on the display unit on the operation unit. When the document size is determined, the copy button standby state of 522 is entered via 521, and the flow of 523 and 521 is repeated until the copy button is pressed. During this time, if the copy button is not pressed within a predetermined time, a time-out 523 is reached, and an end 526 is reached via 525.

  If the copy button is pressed at 522, an image is formed at 524, and the process ends at 526 via 525.

  FIGS. 5A to 5E show the results of reading an original under each condition by this original size detection method.

  FIG. 5A is a diagram showing a state in which the standard size document 504a is correctly arranged at the document stacking position.

  FIG. 5B is a diagram showing a state where the standard-size document 504b is set obliquely and the printout result 504b '.

  FIG. 5C is a diagram showing a state where the standard-size document 504c is set so as to be shifted in the main scanning direction, and the printout result 504c ′.

  FIG. 5D is a diagram showing a state in which an irregular size original 504d smaller than the standard size is set, and a printout result 504 (d) ′.

  FIG. 5E is a diagram showing a state in which a non-standard size original 504e larger than the standard size is set, and a printout result 504e '.

  For example, in FIG. 5A, 504a indicates a document, L indicates a document width, and 511 and 512 indicate document edge positions. Reference numeral 529 denotes a photoelectric conversion device, which forms an image on the photoelectric conversion device via a light source and an optical system (not shown), and can obtain a photoelectric conversion device output as shown in FIG. Here, reference numeral 508 shows an example of light distribution when a light source (not shown) reads a white reference plate (not shown). Reference numeral 509 denotes an image tip (abutting position), and reference numeral 507 denotes an example of a light distribution of a document 504a. Reference numeral 510 denotes an original width L, and reference numerals 511 and 512 denote end positions of the original.

  Further, in the size detection method using the photoelectric conversion device as the document size detection means in the main scanning direction as shown in FIG. 5G, a document detection determination level as shown by 529 is set. The standard document size corresponding to the size in the main scanning direction from 512 main scanning pixel positions is output as a detection result.

  That is, since the standard size area is determined to be the original area, 504b ', 504c', 504d ', and 504e' are output as dotted line image images in which image noise is placed on the portion indicated by the white oblique line on the black background in the figure. . In addition, the conventional malfunction becomes remarkable under the following conditions.

  A. The pressure plate and ADF are open.

  B. The platen / ADF belt is very dirty.

Next, an example using the photoelectric conversion device of the present embodiment will be described for each configuration of the image forming apparatus.
<Structure 1> While reading a document with a photoelectric conversion device, a region outside the document is replaced with a predetermined density level in real time.

  FIG. 6 shows an operation image.

  6 (g), (h), and (i) show a pressure plate opening model, a pressure plate closing model, and an ADF model, respectively. The detailed configuration of the model will be described below.

  First, the configuration of FIG. 6G is as follows. Reference numeral 601 denotes a leader portion. Reference numeral 602 denotes a pressure plate for pressing the document, and reference numeral 603 denotes an elastic black sheet or specular sheet (which is possible by adjusting the threshold value even in white, but in order to reduce the misjudgment rate, Alternatively, a mirror sheet is preferable), and a function of pressing the original 604 against the original platen glass 605 and a function of suppressing image noise by causing the outside area of the non-standard original to be read in white are provided.

  Reference numeral 607 denotes a document illuminating unit, which is used for a document size detection operation synchronized with the closing operation 606 of the pressure plate 602 together with the CMOS sensor 629 and the reflective document size detection unit 613. Incidentally, reference numerals 611 and 612 indicate document widths.

  Reference numeral 614 denotes a reflection type document size detection means in the main scanning direction. FIG. 6 (h) is a diagram illustrating a pressure plate closed state of the model (g). Similarly, FIG. 6 (i) is an ADF model having an ADF (auto document feeder) 627 and a document conveying belt 628, and a reflection-type document size detecting means 614 in the main scanning direction on the reader side, a sub-side on the reader side. A model in which a reflection type document size detection means 613 in the scanning direction is mounted is shown.

  An actual operation image is shown as a block diagram in FIG. A block 621 represents a document size detection by a document size detection unit or a size input from an operation unit (not shown). The reason why this document size detection is necessary in advance is that if the print paper is not fixed in advance, the transport timing of the print paper will be delayed and the total time until printout will be longer. This is a necessary function to output the desired copy output in a short time without waiting.

  When the copy start button is pressed in 622, a paper feed cassette of the original size detected in 621 is selected, paper feeding is started 623, and scanning of the original by the reader is started 624 at the same time. When the scanning of the original is started, when the pressure plate 602 is in the closed state, the reading value of the CMOS sensor 629 is substantially “0” for the elastic black sheet or specular sheet portion indicated by 603, and the pressure plate 602 is also opened. Even in this state, the read value of the CMOS sensor 629 is “0”, which is lower than the document detection threshold level (not shown). Therefore, in the block 625, a document area signal is generated in a portion exceeding the threshold value, and the outside area of the document is replaced with a VTOP signal level shown in FIG. To do. 626 performs image processing on the approximate original area signal, prints it on a print sheet at 630, and outputs 631 from the printer.

  FIGS. 6A to 6E show the results of reading the document under each condition by the method described above.

  FIG. 6A is a diagram showing a state in which the standard size document 604a is correctly arranged at the document stacking position. Reference numerals 611 and 612 denote document edge positions.

  FIG. 6B is a diagram showing a state where the standard-size document 604b is set obliquely and the printout result 604b '.

  FIG. 6C is a diagram showing a state where the standard-size document 604c is set while being shifted in the main scanning direction, and the printout result 604c ′.

  FIG. 6D is a diagram showing a state in which a non-standard size original 604d smaller than the standard size is set, and a printout result 604d '.

  FIG. 6E is a diagram showing a state where a non-standard size original 604e larger than the standard size is set and printout results 604e 'and 604e ".

  (In practice, in the case of an irregular document, a paper size that is one size larger than the original document is selected).

  Here, the replacement control of the area data outside the document will be described using the CMOS sensor main scanning output area graph of FIG.

  Reference numeral 608 denotes the state of FIG. 6A, in which the range of the document end regions 611 and 612 is set as a document region, and the shaded portion indicated by 620 is replaced with a VTOP level (not shown) by a comparator means (not shown).

  Similarly, reference numeral 609 denotes the state shown in FIG. 6B. Since the document is inclined, the document occupation area varies depending on the document scanning position. For example, a vertical stripe line region γ ′, γ ″ section of 618 ′, 618 ″ in the drawing is a period in which image noise may occur, and is a section on which replacement processing is performed according to the data level. Therefore, a document outside replacement process using a CMOS sensor output comparator process is executed from the document abutting reference position, and image noise corresponding to the main scanning offset is removed. Incidentally, the state shown in FIG. 6C shown in FIG. 6C is also substantially the same processing, and the abutting offset of the α section indicated by 616 is replaced with a predetermined level of data as an area outside the document, and the offset from the abutting position. Thereafter, an image corresponding to the document width L ′ is read.

  Next, the case of an irregular size document will be described with reference to 632 and 633.

  Reference numeral 632 denotes an example when a document 604d smaller than the standard size 604d 'is read as shown in FIG. At this time, the document width is smaller than the standard-size paper width in the main scanning direction, and processing outside the document region is performed on the shaded portion 620. Similarly, for 633, as shown in FIG. 6E, a paper size that is one side larger than the other example and larger than the other examples is selected. Further, 615L ′ + 619θ obtained by adding θ indicated by 619 is recognized as the document area, and the area outside the 620 shaded area is processed.

  The above description will be supplemented with reference to FIG.

  Reference numeral 1301 denotes a state in which the document 1305 is set on the leader portion on the basis of abutment. At this time, if the light source 1306 set on the mirror base unit 1307 is controlled to be turned on, the image of the main scanning of the document is connected to the CMOS sensor 1309 via the first, second, and third mirrors (not shown) and the lens barrel 1308. Imaged.

  Here, since the image is rotated 180 degrees through the lens barrel, the document abutting position with reference to the CMOS sensor driving synchronization signal 1319 is assumed to be the Xc 1310 position, that is, the synchronization signal of 1319 is countered by “0”. The counter can be set to “200” 1321 when “1320” is set. Similarly, the document edge position can also be defined as a counter “3710” 1322, and the main scanning readable pixel last pixel can also be defined as a counter “4000” 1323.

  That is, the document area can be designated by a count value based on the counter.

Therefore, in the example 1302 in which the document is set with an offset, when the offset amount is D1304,
This represents a state in which the document 1311 is set on the reader unit on the basis of abutment. At this time, when the light source 1312 set on the mirror base unit 1313 is controlled to be turned on, first, second, third mirrors and lenses (not shown) are displayed. A document main scan image is formed on the CMOS sensor 1315 via the lens barrel 1314. Here, since the image is rotated 180 degrees through the lens barrel, the document abutting position with reference to the CMOS sensor driving synchronization signal 1330 is Xc 1316 on 1329, and the start position of the synchronization signal of 1330 is set to the counter “0”. When “1324” is set, the counter becomes “200” 1325. Further, the offset Dc 1317 described above becomes the counter “300” 1316. Hereinafter, the document edge position can also be defined as the counter “3810” 1327, and the last pixel capable of main scanning reading can also be defined as the counter “4000” 1328.

  As described above, in the CMOS sensor outside-document-area data replacement period 1331 and 1332, the document offset is automatically set by performing the outside-area replacement processing for the CMOS output from 1133 1333 and 1334 1 The replacement process will be performed.

  Next, a description will be given using the flowchart shown in FIG.

  First, an original is set in 1001, and it is detected whether a copy button is pressed in 1003 through 1002. If no, the flow goes to the timeout detection flow of 1023, and if there is no operation by the operator for a predetermined time, the control is terminated at 1024. If there is still time remaining until timeout, the flow proceeds to a flow for determining the opening / closing operation of the document feeder such as the pressure plate 1025 and the ADF. Here, if no, the copy button standby state is entered again via 1026 and 1002. If the platen is closed in the flow 1025, the original size detection operation 1027 is performed. At this time, the document width detection method in the main scanning direction does not particularly differ between the photoelectric conversion device and the reflective document size detection means.

  The detected document size is stored in 1028, displayed in 1029 as a detection result on the display unit on the operation unit, and the process returns to the copy button standby flow of 1003. Next, when the copy button is pressed, the flow proceeds to an open / close operation determination flow of the document feeder such as ADF 1004. Here, if yes, the middle flow is skipped and the process moves to 1009. If no, the operation mode of the photoelectric conversion device is controlled as a document size detection mode in 1005, and the document size is detected in 1006.

  When the document size is detected, the document size is stored by 1007 and displayed on the display means on the operation unit by 1008. Subsequently, in 1010, the operation mode of the photoelectric conversion device is started as a document reading setting, shading correction is performed in 1011, a scanning area is determined from the detected document size, and document scanning is started 1012.

  When document scanning is started, the process proceeds to a sub-scanning area determination flow 1014 through 1013. If document scanning is completed, the process proceeds to 1015 as no, and the control is terminated. In the case of yes, via 1016, in 1017, if it is determined that the area is outside the document based on the determination result of the comparator (not shown), the flow moves to 1019 as no and the data is set to the VTOP level. Replace and return to 1020.

  If it is determined in 1017 that the document area is present, scanning is performed in 1018 while the flow is performed, and output is sequentially performed in units of one pixel as an output from the photoelectric conversion device 1021 through 1020. If a main scanning synchronization signal (substitute with a data shift signal of a photoelectric conversion device) is detected in the determination flow of 1022, the result is fed back to the flow of 1013 as yes, and the next sub scanning line is moved. Scan the data. If no in 1022, the flow is fed back to the flow 1016, and the determination control is repeated for each main scanning pixel.

  As described above, by comparing the data outside the original area with the VTOP level in real time while determining the original area mainly using the comparator function of the CMOS sensor, the image noise of the original area is changed from the image data. It becomes possible to eliminate.

<Embodiment 2>
<< Configuration 2 >> Based on the document size detection result detected outside the photoelectric conversion device, the area outside the document is replaced with a predetermined density level.

  Next, a brief description will be given of a case where the outside data area replacement process is performed on the area corresponding to the original area detected by the external device by the photoelectric conversion apparatus.

  FIG. 7 shows an operation image. FIGS. 7 (g), (h), and (i) show a pressure plate opening model, a pressure plate closing model, and an ADF model, respectively. The detailed configuration of the model will be described below.

  First, the configuration of FIG. 7G is as follows. Reference numeral 701 denotes a leader portion. Reference numeral 702 denotes a pressure plate for pressing down the original, and reference numeral 703 denotes an elastic black sheet or specular sheet (which can be adjusted by adjusting the threshold value even in white, but in order to reduce the misjudgment rate, Alternatively, a mirror sheet is preferable), and a function of pressing the original 704 against the original platen glass 705 and an image noise suppressing function by reading the outside area of the non-standard original in white are provided.

  Reference numeral 707 denotes a document illuminating unit, which is used for a document size detection operation synchronized with the closing operation 706 of the pressure plate 702 together with the CMOS sensor 729 and the reflection type document size detection unit 713. Incidentally, reference numerals 711 and 712 indicate document widths. Reference numeral 714 denotes a reflection type document size detection means in the main scanning direction. FIG. 7 (h) is a diagram showing the pressure plate closed state of the model (g). Similarly, FIG. 7 (i) shows an ADF model having an ADF (auto document feeder) 727 shown in 727 and a document transport belt 728, a reflection-type document size detecting means 714 in the main scanning direction on the reader side, and the reader side. This shows a model equipped with a reflection type document size detecting means 713 in the sub-scanning direction.

  The outline of the operation will be described with reference to the block diagram of FIG.

  Reference numeral 721 denotes a document size detection by a document size detection unit or a size input from an operation unit (not shown). The reason why this document size detection is necessary in advance is that if the print paper is not fixed in advance, the transport timing of the print paper will be delayed and the total time until printout will be longer. This is a necessary function to output the desired copy output in a short time without waiting. The next block 732 sets a pixel area corresponding to the determined document size to the CMOS sensor 729.

  When the copy start button is pressed at 722, a paper feed cassette of the original size detected at 721 is selected, paper feed is started 723, and at the same time, scanning of the original by the reader is started 724. When the scanning of the original is started, when the pressure plate 702 is in the closed state, the reading value of the CMOS sensor 729 is substantially “0” in the elastic black sheet or mirror surface portion indicated by 703, and the pressure plate 702 is also opened. Even in this state, the read value of the CMOS sensor 729 is “0”, which is lower than the document detection threshold level (not shown). Therefore, in the block 725, a document area signal is generated in the part exceeding the threshold value, and the outside area of the document is replaced with the VTOP signal level shown in FIG. To do. 726 performs image processing on the approximate original area signal, prints it on the print paper at 730, and outputs 731 from the printer.

  FIGS. 7A to 7E show the results of reading the document under each condition by the method described above.

  FIG. 7A is a diagram showing a state in which the standard size document 704a is correctly arranged at the document stacking position. Reference numerals 711 and 712 denote document edge positions.

  FIG. 7B is a diagram showing a state where the standard-size document 704b is set obliquely and a printout result 704b '.

  FIG. 7C is a diagram showing a state where the standard-size document 704c is set so as to be shifted in the main scanning direction, and the printout result 704c ′.

  FIG. 7D is a diagram showing a state in which an irregular size original 704d smaller than the standard size is set, and a printout result 704d '.

  FIG. 7E is a diagram showing a state where an irregular-size original 704e larger than the standard size is set, and printout results 704e 'and 704e ".

  (In practice, in the case of an irregular document, a paper size that is one size larger than the original document is selected).

  Here, the replacement control of the area data outside the document will be described using the CMOS sensor main scan output area graph of FIG. First, as the basis of the concept, only the data processing result of the CMOS sensor pixel area is reflected in the printout by performing the out-of-original area replacement process for the CMOS sensor pixel area corresponding to the preselected original size area. Shall be allowed to.

  Reference numeral 708 denotes the state of FIG. 7A, where the document end areas 711 and 712 are set as the document area, and the document is set in the same area as the pre-detection area. Since there is no data outside the document area, the replacement process itself is not executed.

  Next, reference numeral 709 denotes the state shown in FIG. 7B. Since the document is inclined, the document occupation area varies depending on the document scanning position. That is, image noise outside the document area may be generated depending on the main scanning reading position inside the document area, and therefore, CMOS output data replacement processing is performed in an area such as a hatched portion 709, for example. Similarly, reference numeral 710 indicates the state of FIG. 7C, and the replacement process is executed for the hatched portion α 716 of 710. An irregular document 719 is in the state of FIG. 7D, and a replacement process is executed for the hatched portion β717 of 719.

  Similarly, reference numeral 720 denotes the state of FIG. 7E, where the document size of 04e ′ is selected to be larger than the other document sizes, and 718 of the document region that exceeds L ′ of 715. The replacement process is executed with only the .gamma.

  In FIG. 7, as an example of using the reflection type document size detection sensor as the document width detection means in the main scanning direction as in the sub-scanning direction, the main scanning width will be described. A method for detecting the image with a sensor such as a CCD will be briefly described.

  FIG. 8 shows a schematic configuration. In the figure, reference numerals 801 and 802 denote reflection type document size detection sensors. The size detection point on the main scanning side is detection of the presence / absence of the document ★ 0 (803), detection point ★ 1 (804) located inside the STMT_R document width, detection point ★ 2 (A5R located inside the document width ★) 805), detection point * 3 (806) located inside the document width of B5, detection point * 4 (807) located inside the document width of A5, A4R, and inside the document width of STMT, LETTER_R, LEGAL Detection point ★ 5 (808), detection point ★ 6 (809) located inside the document width of B5, B4, detection point ★ 7 (810), A4 located inside the document width of LETTER, LEDGER This is composed of detection points * 8 (811) positioned inside the A3 document width, and basically the document size is detected as a combination of the detection results of the main / sub document size detection means.

  That is, the document size detected from the above-mentioned points is only a standard size, and even when the reflection-type document size detection means is used for both main scanning and sub-scanning, the main scanning side is determined from specific pixel data of the CCD and CMOS sensors. Even if judged, there will be no difference in the results.

  Next, the operation will be described with reference to the flowchart of FIG.

  First, an original is set in 1101, and it is detected whether a copy button is pressed in 1103 through 1102. If no, the process moves to the time-out detection flow in 1125, and if there is no operation by the operator for a predetermined time, the control is terminated in 1126. If there is still time left until timeout, the flow proceeds to a flow 1127 for determining the opening / closing operation of the document feeder such as the pressure plate and ADF. If no, the copy button standby state is entered again via 1128 and 1102. If the platen is closed in the flow 1127, the document size detection operation 1129 is performed. At this time, the document width detection method in the main scanning direction does not particularly differ between the photoelectric conversion device and the reflective document size detection means.

  The detected document size is stored in 1130, and is displayed as a detection result on the display unit on the operation unit in 1131, and the process returns to the copy button standby flow in 1103. Next, when the copy button is pressed, the flow proceeds to an open / close operation determination flow of the document feeder such as ADF 1104. Here, if yes, the intermediate flow is skipped and the process moves to 1109. If no, 1105 controls the operation mode of the photoelectric conversion apparatus as the document size detection mode, and 1106 detects the document size.

  When the document size is detected, the document size is stored in 1107 and displayed on the display means on the operation unit by 1108. Subsequently, in 1110, the operation mode of the photoelectric conversion device is started as a document reading setting, shading correction is performed in 1111, a scanning area is determined from the detected document size, and document scanning is started 1112. When document scanning is started, the process proceeds to a sub-scanning area determination flow 1114 via 1113. If document scanning is completed, the process proceeds to 1115 as no, and the control is terminated. In the case of yes, it is determined in 1117 via 1116 whether the main scanning document area is detected in the document size detection operation. If it is the detection region, the flow moves to 1123 as no. If yes in the flow 1117, the process proceeds to 118 to scan the document.

  Next, in the flow of 1119, it is determined from the signal level of the CMOS sensor whether the document area is further within the area detected by the size detection means. It moves to a flow and is replaced with VTOP data by a comparator (VTOP data is converted to FF Hex by an 8-bit A / D converter).

  In the case of yes in the flow of 1119, the pixel is output to the outside of the device pixel by pixel as the output of the photoelectric conversion device 1122 via 1121 without performing the replacement process. When one pixel is output, if a main scanning synchronization signal (shift signal or the like) is detected by 1124 through the flow of 1123, it is fed back to the flow of 1113 as yes. In the case of no, it is fed back to the flow 1116 and the determination control is repeated for each main scanning pixel.

  As described above, by comparing the data outside the original area with the VTOP level in real time while determining the original area mainly using the comparator function of the CMOS sensor, the image noise of the original area is changed from the image data. It becomes possible to eliminate.

<Embodiment 3>
<< Configuration 3 >> Based on the result of detection in the document size detection mode using the photoelectric conversion device, the area outside the document is replaced with a predetermined density level in real time while reading the document.

  Next, a brief description will be given of a case where the photoelectric conversion apparatus is operated in the special mode, that is, the document width detection mode, and the document area outside data replacement processing is performed on the necessary area based on the result.

  FIG. 9 shows an operation image. FIGS. 9G, 9H, and 9I show a pressure plate opening model, a pressure plate closing model, and an ADF model, respectively. The detailed configuration of the model will be described below.

  First, the configuration of FIG. 9G is as follows. Reference numeral 901 denotes a leader portion. Reference numeral 902 denotes a pressure plate for pressing the document, and reference numeral 903 denotes an elastic black sheet or mirror sheet (even if white, it is possible if the threshold value is set to an appropriate value, but in order to reduce the misjudgment rate, Black or a mirror sheet is preferable), and a function of pressing an original 904 against the original platen glass 905 and an image noise suppression function by reading an outside area of an irregular original in white are provided.

  Reference numeral 907 denotes a document illumination unit, which is used for a document size detection operation in synchronization with the closing operation 906 of the pressure plate 902 together with the CMOS sensor 929 and the reflective document size detection unit 913. Incidentally, reference numerals 911 and 912 denote document widths. Reference numeral 930 denotes an end position of another size larger than the standard size.

  Similarly, FIG. 9 (h) is a diagram showing the pressure plate closed state of the model (g). FIG. 9 (i) shows an ADF model having an ADF (auto document feeder) 927 and a document conveying belt 928. The document size detecting means in the main scanning direction of the reader is a CMOS sensor, and the document in the sub-scanning direction. As the size detection means, a model equipped with a reflection type document size detection means 913 is shown.

  The outline of the operation will be described with reference to the block diagram of FIG.

  A block 921 indicates a document size detection mode. A document illumination unit (not shown) arranged at a position where the document width can be read is turned on, and a pixel area of the document reflected light actually input to the CMOS sensor 929 is detected. It shows the operation to do. The document width detection operation 933 of the CMOS sensor can detect an almost accurate document width as long as the document is not tilted. When the copy start button is pressed in 922 in conjunction with the copy start in 922, the document detected in 921 is detected. A paper feed cassette of a size is selected, paper feed is started 923, and document scanning by the reader is started 924 at the same time.

  When the scanning of the original is started, in the closed state of the pressure plate 902, the black sheet or the specular sheet portion having elasticity shown in 903 is practically the reading value of the CMOS sensor 929 is "0", and the pressure plate 902 is also opened. Even in this state, the read value of the CMOS sensor 929 is “0”, which is lower than the document detection threshold level (not shown). Therefore, in the block 925, a document area signal is generated in a portion exceeding the threshold value, and the outside area of the document is replaced with a VTOP signal level shown in FIG. To do. 926 performs image processing on the approximate original area signal, prints on the print paper at 930, and outputs 931 from the printer.

  9A to 9E show the results of reading the document under each condition by the method described above.

  FIG. 9A is a diagram illustrating a state in which the standard size document 904a is correctly arranged at the document stacking position. Reference numerals 911 and 912 denote document edge positions.

  FIG. 9B is a diagram showing a state where the standard-size document 904b is set obliquely and a printout result 904b '.

  FIG. 9C is a diagram showing a state where the standard-size document 904c is set while being shifted in the main scanning direction, and a printout result 904c '.

  FIG. 9D is a diagram showing a state in which an irregular size original 904d smaller than the standard size is set, and a printout result 904d '.

  FIG. 9E is a diagram showing a state where an irregular size original 904e larger than the standard size is set, and printout results 904e 'and 904e ".

  (In actuality, in the case of an irregular document, a paper size 904e 'that is one size larger than the original document is selected).

  Here, the replacement control of the area data outside the document will be described using the CMOS sensor main scan output area graph of FIG.

  Reference numeral 908 denotes the state of FIG. 9A, in which the range of the document edge areas 911 and 912 is a document area, and the document is set in the same area as the previously detected area. Since there is no data outside the document area, the replacement process itself is not executed.

  Reference numeral 909 denotes the state shown in FIG. 9B. Since the document is inclined, the document occupation area varies depending on the document scanning position. That is, image noise outside the document area may occur depending on the main scanning reading position inside the document area. If the document width is detected based on the main scanning data on the sub-scanning point indicated by the document width detection position 932, 933 is detected as the document width from the CMOS sensor output for the document 904b.

  Here, since the document width detection using the CMOS sensor output is performed, strictly speaking, the document width can be detected in units of 42.3 μm when read at a resolution of 600 dpi. Therefore, it is detected from the original detection width corresponding to the original inclination that it protrudes from the set area of the original standard original size. Therefore, the document size selected under this circumstance is not 904b 'but 904b "is selected. Therefore, the replacement processing is performed on the entire hatched portion with respect to the width of L" of 909.

  Similarly, reference numeral 910 denotes the state of FIG. 9C. The document width of the standard document 904c is as indicated by 935 with respect to the document width detection position 934, but from the document abutment reference position to the back of the document. The length to the end is as shown at 936. For this reason, in order to copy the document description without omission, it is necessary to select a standard size that is one size larger than 904c '. Therefore, the replacement process is performed on the α916 offset region and the γ918 region. Further, 931 handling an irregular document shows the state shown in FIG. 9D, and a replacement process is executed for a portion that is insufficient with respect to the standard size and a hatched portion β917 portion of 931.

  Similarly, 932 shows the state of FIG. 9 (e). Since the original size of 904e is larger in the main scanning direction than the standard size 904e ′, a large paper size 904e ″ that contains the original main scanning width is obtained. Accordingly, the document width is an area from 911 to 930, and the hatched area of γ918 is replaced.

  Next, a description will be given using the flowchart shown in FIG.

  First, a document is set in 1201, and it is detected whether a copy button is pressed in 1203 through 1202. If no, the flow goes to the timeout detection flow of 1223, and if there is no operation by the operator for a predetermined time, the control is terminated at 1224. If there is still time remaining until timeout, the flow proceeds to a flow for determining the opening / closing operation of the original conveying apparatus such as the pressure plate 1225 and the ADF. If “no” here, the copy button standby state is entered again via 1226 and 1202. If the platen is closed in the flow 1225, the document size detection operation 1227 is performed. At this time, the document width detection method in the main scanning direction does not particularly differ between the photoelectric conversion device and the reflective document size detection means.

  The detected document size is stored in 1228, displayed as a detection result on the display unit on the operation unit by 1229, and the process returns to the copy button standby flow in 1203. The document size detected by the flow described above is used as output paper (recording paper) of the printer as a main purpose.

  Next, when the copy button is pressed, the flow proceeds to an open / close operation determination flow of the document feeder such as 1204 ADF. If yes, since the output paper (recording paper) of the printer has already been determined, the flow on the way is skipped and the process moves to 1209. If NO, the position information of the document is obtained as pixel information of the CMOS sensor in 1205, the document size is determined in 1206, and the document size and CMOS sensor pixel data are stored in 1207. Also, 1208 displays the detection result on the display means on the operation unit.

  Subsequently, in 1210, the operation mode of the photoelectric conversion device is started as a document reading setting, shading correction is performed in 1211, a scanning area is determined from the detected document size, and document scanning is started 1212.

  When document scanning is started, the process proceeds to a sub-scanning area determination flow 1214 via 1213. If document scanning is completed, the process proceeds to 1215 as no and the control is terminated. In the case of yes, the stored CMOS pixel information is compared with the detected document size at 1217 through 1216, and the document area and the document area outside the selected size are determined. In other words, if it is determined that the area is outside the original, the flow moves to step 1219 as “no”, replaces the data with the VTOP level, and returns to 1220.

  If it is determined in 1217 that the area is the document area, scanning is performed in 1218 while the flow is performed, and output is sequentially performed in units of one pixel as a photoelectric conversion device output from 1221 through 1220. If the main scanning synchronization signal (substitute with the data shift signal of the photoelectric conversion device, etc.) is detected in the determination flow of 1222, the result is fed back to the flow of 1213 as yes, and the process proceeds to the next sub-scanning line. Scan the data. If no in 1222, the process is fed back to the flow 1216, and the determination control is repeated for each main scanning pixel.

  As described above, by comparing the data outside the original area with the VTOP level in real time while determining the original area mainly using the comparator function of the CMOS sensor, the image noise of the original area is changed from the image data. It becomes possible to eliminate.

  As described above, by using the configuration of the present invention, in the conventional image forming apparatus, when an irregular-size original is selected, an output paper (recording paper) larger than the original size is selected. There is a problem that the pressure plate existing in the area outside the non-standard document or the document pressing member of the document feeding (conveying) device is stained, or the pressure plate or the document feeding (conveying) device is open. In the case of the state, it is possible to improve the problem that the outside area of the document becomes black, or the problem that the image noise similar to the above is formed even on the document placed obliquely or offset. .

  In addition, in order to remove the image noise outside the original area, image processing technology such as original area separation processing must be used for video data obtained by A / D converting the output of a photoelectric conversion device such as a CCD. Although real-time image processing could not be performed due to the increase in image processing and delay in image processing, this issue can greatly improve the problem by implementing real-time processing on the photoelectric conversion device side. It becomes.

In particular, the effects listed below are expected. By performing data processing on the photoelectric conversion device side,
I. Since the total time for reading the scan object and outputting the image of the scan object does not change, real-time processing is possible.

  II. It is possible to simplify the image processing circuit and reduce the apparatus cost by reducing the memory of the image processing circuit.

It is a figure explaining the circuit structure of the photoelectric conversion apparatus of this invention. 1 is a block diagram of an image forming apparatus equipped with a photoelectric conversion device of the present invention. 3 is a timing chart of the photoelectric conversion device of the present invention. It is a timing chart which supplements the drive sequence of the photoelectric conversion apparatus of this invention. It is explanatory drawing explaining the phenomenon which is a problem in the conventional image forming apparatus. It is a figure explaining Embodiment 1 of this invention. It is a figure explaining Embodiment 2 of this invention. It is a figure explaining the reference method of the photoelectric conversion apparatus data at the time of main scanning size detection. It is a figure explaining Embodiment 3 of this invention. It is a flowchart explaining the operation | movement of Embodiment 1 of this invention. It is a flowchart explaining the operation | movement of Embodiment 2 of this invention. It is a flowchart explaining the operation | movement of Embodiment 3 of this invention. It is supplementary explanatory drawing of this invention.

Explanation of symbols

129 Shift register 148 Output circuit 149 Charge storage means 151 Photoelectric conversion element block 154 Comparator 155 Pulse generator 158 External CLK
161 selector 201 reader unit 202 reader controller 203 inverter 204 document illumination light source 205 photoelectric conversion device 206 CMOS-SENSOR
212 motor driver 213 optical motor 214 reader interface unit 217 system controller 218 operation unit 219 display means 220 printer unit

Claims (31)

  A plurality of photoelectric conversion means, a plurality of optical signal holding means for holding optical signals of the plurality of photoelectric conversion means, an optical signal output line for outputting an optical signal from the optical signal holding means, and the optical signal output line Reset means for resetting the signal to a fixed potential, drive pulse control means, charge transfer means for reading out the signal of the photoelectric conversion means for each pixel via the optical signal output line, and referencing the charge transfer signal level for each pixel A photoelectric conversion device comprising a comparing means for comparing with a value and replacing with a predetermined luminance level.   The photoelectric conversion device according to claim 1, wherein the drive pulse control unit generates a drive control signal for the photoelectric conversion device.   2. The photoelectric conversion apparatus according to claim 1, wherein the drive pulse control means controls the operation of the comparing means.   2. The reference value is a predetermined criterion level, and an output signal of the photoelectric conversion means is set to a signal level capable of detecting a scanning object (subject, document). The photoelectric conversion device described.   2. The photoelectric conversion device according to claim 1, wherein the predetermined luminance level is an input upper limit potential (VTOP) when the charge transfer signal is guided to the video conversion means.   2. The photoelectric conversion apparatus according to claim 1, wherein the video conversion means is an analog / digital conversion means (A / D converter).   The photoelectric conversion means replaces a signal level outside the scanning object with the predetermined luminance level while performing a scanning operation on the scanning object (subject, original). Photoelectric conversion device.   The special operation mode is characterized in that the reading level of a document support member having a predetermined density located outside the scanning object (subject, original) is used as an auxiliary means for detecting the size of the scanning object (subject, original). The photoelectric conversion device according to claim 1.   The photoelectric conversion device according to claim 1, wherein the photoelectric conversion means is a CMOS sensor. A plurality of photoelectric conversion means, a plurality of optical signal holding means for holding optical signals of the plurality of photoelectric conversion means, an optical signal output line for outputting an optical signal from the optical signal holding means, and the optical signal output line A reset means for resetting the signal to a fixed potential, a drive pulse control means for controlling the drive mode of the photoelectric conversion means, and a charge transfer means for reading out the signal of the photoelectric conversion means for each pixel via the optical signal output line. In the photoelectric conversion device
A special operation mode of the photoelectric conversion means controlled by the drive pulse control means, a comparator means for comparing the signal level in the special operation mode state with a reference value for each pixel, and a comparison result in the special operation mode state. Accordingly, a photoelectric conversion apparatus comprising: means for setting an effective area of the photoelectric conversion means; and means for replacing an output outside the effective area with a predetermined luminance level determined in advance.   The photoelectric conversion apparatus according to claim 10, wherein the drive pulse control unit controls generation of a drive control signal of the photoelectric conversion apparatus.   11. The photoelectric conversion apparatus according to claim 10, wherein the drive pulse control means controls the operation of the comparing means.   11. The photoelectric operation mode according to claim 10, wherein the special operation mode is an operation mode for detecting a relative position where a scanning object (subject, original) is set from a read signal level of the photoelectric conversion means. Conversion device.   11. The photoelectric conversion apparatus according to claim 10, wherein the special operation mode is an operation mode for detecting a size of a scanning object (subject, original) from a read signal level of the photoelectric conversion means.   The special operation mode is characterized in that the reading level of a document supporting member having a predetermined density located outside the scanning object (subject, original) is used as an auxiliary means for detecting the size of the scanning object (subject, original). The photoelectric conversion device according to claim 10.   11. The reference value is a predetermined criterion level, and an output signal of the photoelectric conversion means is set to a signal level capable of detecting a scanning object (subject, document). The photoelectric conversion device described.   11. The photoelectric conversion device according to claim 10, wherein the predetermined luminance level is an input upper limit potential (VTOP) when the charge transfer signal is guided to the video conversion means.   11. The photoelectric conversion apparatus according to claim 10, wherein the video conversion means is an analog / digital conversion means (A / D converter).   The photoelectric conversion unit replaces a signal level outside the effective area of the photoelectric conversion unit with the predetermined luminance level while performing a scanning operation on a scanning object (subject, original). 10. The photoelectric conversion device according to 10.   The photoelectric conversion device according to claim 10, wherein the photoelectric conversion means is a CMOS sensor. A plurality of photoelectric conversion means, a plurality of optical signal holding means for holding optical signals of the plurality of photoelectric conversion means, an optical signal output line for outputting an optical signal from the optical signal holding means, and the optical signal output line A reset means for resetting the signal to a fixed potential, a drive pulse control means for controlling the drive mode of the photoelectric conversion means, and a charge transfer means for reading out the signal of the photoelectric conversion means for each pixel via the optical signal output line. In the photoelectric conversion device
A photoelectric conversion apparatus comprising: effective area setting means of the photoelectric conversion means based on input information via an external interface of the photoelectric conversion apparatus; and means for replacing an output outside the effective area with a predetermined luminance level .   The photoelectric conversion apparatus according to claim 21, wherein the drive pulse control means controls generation of a drive control signal of the photoelectric conversion apparatus.   The photoelectric conversion apparatus according to claim 21, wherein the drive pulse control means controls the operation of the comparing means.   The photoelectric conversion device according to claim 21, wherein the external interface includes a read signal output in the photoelectric conversion device and a control signal input from an external system.   The photoelectric conversion apparatus according to claim 21, wherein the input information is size information of a scanning object (subject, document) detected or set by an external system.   The photoelectric conversion apparatus according to claim 21, wherein the effective area setting unit sets a scanning object (subject, document) reading area of the photoelectric conversion unit and a reading area outside the scanning object.   The photoelectric conversion apparatus according to claim 21, wherein the predetermined luminance level is an input upper limit potential (VTOP) when the charge transfer signal is guided to the video conversion means.   The photoelectric conversion apparatus according to claim 21, wherein the video conversion means is an analog / digital conversion means.   The photoelectric conversion unit replaces a signal level outside the effective area of the photoelectric conversion unit with the predetermined luminance level while performing a scanning operation on a scanning object (subject, original). 21. The photoelectric conversion device according to item 21.   The special operation mode is characterized in that the reading level of a document support member having a predetermined density located outside the scanning object (subject, original) is used as an auxiliary means for detecting the size of the scanning object (subject, original). The photoelectric conversion device according to claim 21.   The photoelectric conversion device according to claim 21, wherein the photoelectric conversion means is a CMOS sensor.

Images