JPH1013621A - Optical system reader - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stop an optical reading means at a proper position without using another member such as a detection sensor. SOLUTION: This device has 1st image read control for reading the image of original placed on contact glass 8 by moving an optical reading means 11 and 2nd image read control for reading the image of original by moving the original at fixed speed through an automatic original conveying part to the optical reading means 11 stopped at the prescribed image read position. In this case, when reading the image of original under the 2nd image read control, a white member 16 which is to exist just above the position, where the optical reading means 11 is moved and stopped, is read, the provided image information is converted into the binary level of black and white by the prescribed threshold value and when the number of bits recognized as black is more than the previously set discriminative number, it is judged that the stop position is not the image read position so that the start of image read of the original can be regulated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a facsimile apparatus using plain paper as recording paper, and an optical reading apparatus applied to a copying machine.

[0002]

2. Description of the Related Art Conventionally, this kind of technology has been
There is a document feeding device described in Japanese Patent Application Laid-Open No. 2-53685. According to this device, the detection sensor is provided above the place where the optical reading unit is to be positioned.

[0003]

Conventionally, a mark such as black is provided within a readable area of the light receiving element of the optical reading means and a predetermined distance from the reading position, and is sent from the document feeder. When reading the original, the optical reading unit reads the black mark, advances by a predetermined distance therefrom and stops, thereby positioning the optical reading unit. However, when the optical reading means is advanced by a predetermined distance after reading the black mark, if the motor loses synchronization for some reason, the optical reading means is not at the correct position. Nevertheless, since the control unit of the image forming apparatus determines that the image is normal and starts the reading operation, an abnormal image such as a black image or a half black image may be generated.

In the document feeder described in Japanese Utility Model Laid-Open No. 2-53685, a detection sensor is provided at a stop position to confirm that the optical reading means is at a correct position. Requires a space for mounting the detection sensor, and thus the size of the device is increased. In addition, since an electrical port is also required, this leads to an increase in cost including the cost of the sensor alone.

[0005] The present invention solves such problems,
It is an object of the present invention to provide an optical reader that can position an optical reader at a correct position without using a detection sensor.

[0006]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a first image reading control for reading an image of a document placed on a contact glass by moving an optical reading means, A second image reading control for reading the image of the document by moving the document at a constant speed by the document feeding device with respect to the optical reading device stopped at the reading position; An index is provided within a light-receiving area of the element and at a position at a predetermined distance from the image reading position, and the first image reading control is switched to the second image reading control to move the optical reading unit to the image reading position. When causing the optical reading means to read the index, from the time when the optical reading means reads the index, advance the optical reading means by the predetermined distance and stop the optical reading means. In reading optical system device including a control unit, optically disposed a stable color member substantially directly above the position of the image reading position in the document feeder, the second
When switching to the image reading control, image information obtained by performing scanning at the position where the optical reading means stops is converted to a binary level of white and black at a predetermined threshold value, If the number of recognized bits is smaller than the predetermined number of determinations, the stop position is determined to be the image reading position and the image reading of the document is started, and the number of bits recognized as the black level is equal to or greater than the number of determinations. Is provided with a judging means for judging that the stop position is not the image reading position and restricting the start of the image reading of the document. With this configuration, it is confirmed that it is at the correct position using the light receiving element of the optical reading means.
A space for mounting the detection sensor is not required unlike the related art.

In addition, the determination means determines whether the stop position of the optical reading means is acceptable based on several bits obtained from image information on the near side and the back side of the optically stable color member. It is characterized by. With such a configuration, it is possible to reduce the data used for determining whether the position of the optical reading unit is acceptable or not.

Further, all the bits of the image information obtained by performing scanning at the position where the optical reading means is stopped are converted into binary levels, and all or some of these binary level bits are used. When the determining unit determines that the stop position of the optical reading unit is the image reading position, the image information of the document read by the optical reading unit is once stored in the storage unit, and then the storage unit For each line of the image information stored in the above, the optically stable color member is read and all the bits corresponding to the bits recognized as the black level are rewritten to white, or the optical reading unit reads the bits. For each line of image information
Image information is stored in the storage unit while the bit corresponding to the bit recognized as a black level by reading the optically stable color member is rewritten to white.
With such a configuration, black vertical stripes generated by dust or the like adhering to the image reading position can be rewritten to white.

Further, the optically stable member is a white member. With such a configuration, the binary level can be detected accurately.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is an external view of a facsimile apparatus to which the apparatus of the embodiment of the present invention is applied, and FIG. 2 is a side view showing a main part of the apparatus of the embodiment of the present invention. The automatic document feeder 2 separates and feeds each document, and reads an image of the document and records the read image or image information received via a telephone line on plain paper.
The recording unit 3 is a paper feed unit that stores paper to be fed to the image reading / recording unit 2. A facsimile apparatus to which the apparatus of the present embodiment is applied includes an automatic document feeder 1 and an image reading / recording section 2.
And a paper feed unit 3.

Reference numeral 4 denotes a document tray for placing a document to be set on the automatic document feeder 1, reference numeral 5 denotes a holding plate which opens and closes on the image reading / recording unit 2, and reference numeral 6 denotes an image reading / recording unit 2. And an operation panel 7 for sending various instructions to the apparatus, and a paper discharge tray on which image information is recorded and on which discharged paper is stacked. Here, for convenience of explanation, in the facsimile apparatus shown in FIG. 1, the side having the operation panel 6 is the near side, the opposite side is the back side, the side having the automatic document feeder 1 is the left side, and the opposite side is the right side. explain. That is, the holding plate 5 is rotatably installed at the back of the image reading / recording unit 2 and opens and closes from the near side.

In FIG. 2, reference numeral 8 denotes a contact glass provided on the uppermost portion of the image reading / recording unit 2, reference numeral 9 denotes a guide plate provided on the left side of the contact glass 8 and below the automatic document feeder 1, and reference numeral 10 denotes A reading glass 11 provided on the guide plate 9 indicates an optical reading means for reading an image of a document set on the contact glass 8 or a document passing through the reading glass 10. These contact glass 8, guide plate 9, reading glass 10, and optical reading means 11
Is a member related to the image reading / recording unit 2. Further, the optical reading means 11 includes a light source 11a for irradiating the original with light, a lens 11b for converging light reflected from the original, and a light receiving element 11c for receiving light passing through the lens 11b.

Reference numeral 12 denotes a pickup roller, 13 denotes a pair of separation / conveyance rollers for separating and conveying a document one by one, 14 and 15 denotes a pair of conveyance rollers, 16 denotes a white member that contacts the reading glass 10, and 17 denotes a white member. A pressing member for pressing the reading glass 10, a pair of discharge rollers 18 for discharging a document to the outside, and a reference numeral 19 a document guide plate.

When a plurality of documents are transported using the automatic document transporter 1, the documents are first set with the image surface facing upward. Then, the original is transported from the uppermost portion to the separation transport roller pair 13 by the pickup roller 12, where the original is separated one by one and sent to the transport roller pair 14. Further, the original is fed between the white member 16 and the reading glass 10 at a constant speed by the pair of conveying rollers 14 and 15. At this time, the image surface of the document comes into contact with reading glass 10. Then, the document that has passed between the white member 16 and the reading glass 10 is discharged to the outside by a discharge roller pair 18.

In FIG. 2, point A is a standby position of the optical reading means 11, point B is a position on the contact glass 8 where the leading edge of the original is set in an area where the original can be placed, and point C is the contact glass 8. , The position of the rear end of the document within the area where the document can be set, and the point D indicates the position immediately below the white member 16.

The optical reading means 11 usually stands by outside the area where the original can be placed on the contact glass 8 and on the right side of the contact glass 8 as shown at point A in the figure. Then, when reading the original set on the contact glass 8, as shown in FIG.
In step 11, the document is scanned and read while moving from point A to point B and further from point B to point C. When reading a document set on the automatic document feeder 1, the optical reading means 11 moves from point A to point D in the drawing and stops. Then, the originals sent one by one by the automatic original feeder 1 are scanned and read.

FIG. 3 is an enlarged view of a portion K in FIG. 2, and 9a indicates a hole. A hole 9a extending from the near side to the far side is formed on the surface of the guide section 9 located directly below the white member 16. A reading glass 10 is provided on the surface of the guide 9 so as to cover the hole 9a.

FIG. 4 is a block diagram showing a control system of the facsimile apparatus shown in FIG. 1. Reference numeral 20 denotes a reading unit for reading an original, 21 a recording unit for recording a received image or report,
22, an encoding / decoding unit for encoding / decoding image information; 23, a system control unit for controlling the entire system;
Is a system memory which is a work area used for system control, 25 is an image information memory for accumulating and storing image information as needed, and 26 is a key, L
An operation display unit provided with an ED, an LCD, etc. to allow an input operation;
Is a communication control unit that controls transmission, 28 is a modem that modulates / demodulates an analog signal between the telephone line and the communication control unit 27,
Reference numeral 29 denotes a DTMF detector sent from the line.

In FIG. 2, if the maximum size that can be loaded on the contact glass 8 is the distance between the points B and C in FIG.
An area from which an image is not read is between the points C and D. A black point is provided between the points C to D. As shown in FIG. 2, the black point is provided on the leftmost side of the contact glass 8 (the black point at this position is referred to as a black point E1) or the guide plate 9 (the black point at this position is referred to as a black point E2). In this embodiment, an apparatus provided with the black point E2 will be described.

FIG. 5 is a plan view showing the arrangement of the black spots E2. The black point E2 has a size of, for example, about 2 mm × 2 mm, is arranged on the positioning sheet 30 on a white background, and is positioned such that the black point E2 is located at a position that is almost exactly L2 away from the point D. 30 sticks to the guide plate 9. Here, the length of the positioning sheet 30 in the main scanning direction is set to L4 larger than the black point E2. The position of the black point E2 in the main scanning direction may be within the range of the maximum readable size of the document as shown in FIG. 5, or may be within the range of dummy bits outside the range of the maximum readable size. good.

Next, a description will be given of a movement control for moving the optical reading means 11 to the point D in order to read a document set in the automatic document feeder 1.

First, in FIG. 5, the optical reading means 11
Reading starts from the point F which is the start of the positioning sheet 30 and the point G which is the start of the black point E2, and from the obtained image information in the positioning sheet 30, the point G at which the optical reading means 11 becomes the reference position. A few bits are extracted to determine whether or not the The number of bits for determination is a bit number corresponding to a range L3 (for example, 8 mm) that does not deviate from the size L4 of the width of the positioning sheet 30. In the case of a resolution of 16 lines / mm, as shown in FIG. 6, 128 bits (16 × 8
= 128) is detected as a white level. Further, when the optical reading means 11 advances in the direction of point D and reaches point G, a bit indicating a black level appears as shown in FIG. Here, since the size of the black point E2 is 2 mm, 32 bits (16 × 2 = 32)
It represents the black level. In the present embodiment, in consideration of the reading and the error of the size of the black point E2, 19 to 45
When the bit black level is represented, the system control unit 23 determines that the black point E2 has been detected. After determining that the black point E2 has been detected, the optical reading means 11 advances by the distance L2 and stops.

Next, in order to determine whether or not the stop position of the optical reading means 11 coincides with the point D, the optical reading means 11 is used.
Is a white member 16 that should be located directly above
Read. Then, a predetermined threshold value is set to the white member 16.
Is converted into a monochrome binary level. If, after the conversion, the number of bits recognized as black is smaller than the determined number (for example, 2), the stop position is determined to be correct and the document reading mode is entered, and the number of bits recognized as black is determined as the determined number (for example, 2). If so, it is determined that the stop position is not correct, and the flow proceeds to the next flow without reading. It is better to determine the number of bits as a criterion for determining whether or not the stop position is acceptable by assuming a level at which erroneous determination is not made when dust is attached. When the system control unit 26 determines that the stop position is not correct, for example, the process returns to the point H, performs the detection processing of the black point E2 again, further proceeds by L2, stops, and stops the white member 16. After reading, the pass / fail of the stop position is determined again. If it is still determined to be abnormal, a method of notifying the user of the machine abnormality and prompting a service technician to request repairs, or displaying the abnormality to the user when the abnormality is first determined to be service. There is a method to ask a man for repair.

With such a configuration, the optical reading means 11
Since the correct position is confirmed using the light receiving element 11c, the space for mounting the detection sensor as in the related art is not required, and the size can be reduced accordingly.
Further, an electric port for analyzing the detection result of the detection sensor is not required, and the cost of the detection sensor alone is unnecessary. Further, only by detecting the black point E2, it is possible to reliably detect the correct position as compared with a method in which the optical reading unit 11 is moved by a predetermined distance to the reading position after the detection.

In this embodiment, the white member is set at point D.
In all bits of the image information obtained by reading 16,
The number of bits used to determine the pass / fail of the position of the optical reading means 11 is not specified. When the maximum readable size is B4, 16 × 257 = 4112 bits may be read, or the center portion or the like may be read. You may read several bits (16 bits). Further, when there are dummy bits other than the maximum reading size, the reading may be performed by adding the dummy bits to 4112 bits. Further, the position of the black point may be set to the position indicated by E1 in FIG. In this case, the moving distance is L1.
Furthermore, the position of the black point may be set to a position indicated by E0 between point A and point B.

FIG. 8 shows a case in which some abnormality occurs between the time when the optical reading means 11 reads the black point E2 and the time when the optical reading means 11 reaches the point D, and the white portion of the white member 16 cannot be read. The cases shown in (a) to (c) can be considered. That is, FIG. 8A shows a case where the front side of the optical reading unit 11 hits an obstacle and stops, but the back side enters the white member readable range L5, and FIG. FIG. 8C shows a case where the back side of the reading unit 11 has hit the obstacle, but the front side has entered the white member readable range L5. FIG. 8C shows that the center of the optical reading unit 11 hits the obstacle. This shows a case where the entirety did not fall within the white member readable range L5 due to the error.

As described above, considering the case where the white portion of the white member 16 cannot be read, it can be seen that the level of the bit read by at least one of the front side and the back side of the optical reading means 11 becomes the black level.

As a data processing method at this time, the reading range L5 of the white member 16 is read in the main scanning direction, binarization is performed on all bits of the obtained image information, A method in which a black level bit is extracted from several bits of a portion corresponding to the back side and used as data for determining the position of the optical reading unit 11, or the front side and the back side of the reading range L5 of the white member 16 are used. reading,
There is a method in which binarization is performed on several bits of the obtained two pieces of image information, and a black level is detected and used as data for determining the position of the optical reading unit 11.

In the former case, since the binarization is performed for all bits, the black level data obtained therefrom can be applied to image processing described later with reference to FIG. In the latter case, the white member 16 is determined by making a determination at two positions on the near side and the far side in the optical reading means 11.
The reading range can be reduced as much as possible, and the optical reading means 11 can be reliably determined to be at the correct position.

In the state shown in FIG. 8C, when the stopped position is at the point M shown in FIG. 3, that is, in the vicinity of the readable range, it is desirable to make the determination over the entire read bit range.

When reading the white member 16, FIG.
As shown in (2), when the number of bits smaller than the number of determinations becomes the black level, it is determined that the stop position is correct, and reading of the document is started. However, the black level is
If the image is caused by dust or the like attached to the image, the device cannot recognize the dust and, as shown in FIG. Will appear as vertical stripes, causing user complaints.

Therefore, a bit recognized as a black level when the white member 16 is read is stored in advance, and all the image information of the read original is once stored in the image information memory 25.
Then, all the bits of the image information of the document stored in the image information memory 25 corresponding to the bits recognized as the black level by reading the white member 16 are rewritten to white as shown in FIG. By performing such processing, the vertical black stripes are eliminated, and the impression when the image is viewed is not lost. It should be noted that while reading the image of the original, processing is performed such that the bits of the image information of the original corresponding to the bits previously recognized as the black level by reading the white member 16 are converted to white and then stored in the image information memory 25. The same effect can be obtained by performing the above.

[0034]

According to the present invention configured as described above, the following effects can be obtained.

According to the first aspect of the present invention, since the correct position is confirmed using the light receiving element of the optical reading means, a space for mounting the detection sensor as in the related art is not required. The size can be reduced accordingly.
Further, an electric port for analyzing the detection result of the detection sensor is not required, and the cost of the detection sensor alone is unnecessary. In addition, only by detecting the index, it is possible to reliably detect that the optical reading unit is at the correct position, as compared with a method in which the optical reading unit is moved by a predetermined distance to the reading position after the detection.

According to the second aspect of the present invention, the data used for judging the pass / fail of the position of the optical reading means is reduced, so that the judgment time can be shortened.

According to the third aspect of the present invention, the data of all bits of the optically stable color member detected for judging whether the position of the optical reading means is right or wrong is utilized to set the image reading position. By rewriting the black vertical stripes generated by the attached dust to white, the black vertical stripes can be erased.

According to the configuration of the fourth aspect, it is possible to accurately detect the binary level.

[Brief description of the drawings]

FIG. 1 is an external view of a facsimile apparatus to which an apparatus according to an embodiment of the present invention is applied.

FIG. 2 is a side view showing a main part of the device according to the embodiment of the present invention.

FIG. 3 is an enlarged view of a portion K in FIG. 2;

FIG. 4 is a block diagram showing a control system of the facsimile apparatus shown in FIG.

FIG. 5 is a plan view showing an arrangement state of black spots E2.

FIG. 6 is a graph showing a binarization level at a point H which is a reading start point.

FIG. 7 is a graph showing a binarization level at a point G where a black point E2 is located.

FIG. 8 is an explanatory diagram showing a state when the optical reading unit has hit an obstacle and stops.

FIG. 9 is a graph showing an example of a case where when reading a white member, the number of bits smaller than the number of determinations becomes a black level, and it is determined that the stop position is correct.

FIG. 10 is a graph showing image information when an image of a document is read in the state of FIG. 9;

11 is a graph showing image information after performing image processing in the state of FIG. 9;

[Explanation of symbols]

1: Automatic document feeder, 2: Image reading / recording unit, 3:
Document feeder, 4 Document tray, 5 Holding plate, 6 Operation panel, 7 Output tray, 8 Contact glass, 9 Guide plate, 9a Hole, 10 Reading glass, 11 Optical reading Means, 11a: light source, 11b: lens, 11c: light receiving element, 12: pickup roller, 1
3… Separated transport roller pair, 14, 15… Transport roller pair, 16
... white member, 17 ... pressing member, 18 ... discharge roller pair, 19
... Document guide plate, 20 ... Reading unit, 21 ... Recording unit, 22 ... Encoding / decoding unit, 23 ... System control unit, 24 ... System memory, 25 ... Image information memory, 26 ... Operation display unit,
27: Communication control unit, 28: Modem, 29: DTMF detector, 30: Positioning sheet.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical indication location H04N 1/107 H04N 1/12 Z

Claims (4)

[Claims] A first image reading control for reading an image of a document placed on a contact glass by moving an optical reading means; and a document feeding control for the optical reading means stopped at a predetermined image reading position. A second method for reading an image of a document by moving the document at a constant speed by a paper device
Image reading control, within the light-receiving area of the light-receiving element of the optical reading means,
An index is provided at a position at a predetermined distance from the image reading position, and when switching from the first image reading control to the second image reading control to move the optical reading unit to the image reading position, the optical reading unit An optical system reading device comprising: a control unit that causes the optical reading unit to advance by the predetermined distance and stop after the optical reading unit reads the index. A member of an optically stable color is provided at a position substantially directly above the image reading position in the apparatus, and reading scanning is performed at a position where the optical reading means stops when switching to the second image reading control. The converted image information is converted into a binary level of black and white with a predetermined threshold value. If the number of bits recognized as a black level is smaller than a predetermined number of determinations, the stop position is set to the image reading level. When the number of bits recognized as the black level is equal to or greater than the determined number, it is determined that the stop position is not the image reading position, and the image reading of the document is started. An optical system reading device, further comprising a determination means for restricting the optical system. 2. The method according to claim 1, wherein the determination unit determines whether or not the stop position of the optical reading unit is acceptable based on several bits obtained from image information on the front side and the back side of the optically stable color member. The optical system reader according to claim 1, wherein: 3. Converting all bits of image information obtained by performing scanning at a position where the optical reading means stops at a binary level, and using all or a part of these binary level bits. When the determining unit determines that the stop position of the optical reading unit is the image reading position, the image information of the document read by the optical reading unit is once stored in the storage unit, and then the storage unit For each line of the image information stored in the above, the optically stable color member is read and all the bits corresponding to the bits recognized as the black level are rewritten to white, or the optical reading unit reads the bits. For each line of the read image information, read the optically stable color member and rewrite the bit corresponding to the bit recognized as the black level to white while storing the image information in the storage means. The optical system reading device according to claim 1, wherein the optical system reading device is stored. 4. The optical system reading device according to claim 1, wherein said optically stable color member is a white member.