CN1410939A - Automatic paper feeding device and method for adjusting depth of field - Google Patents

Abstract

An automatic paper feeder and its field depth adjusting method, the device has a guide slot for feeding in the file to be scanned, a scanning window for the image pickup unit to pick up the image of the object to be scanned is opened at a certain position of the guide slot; the device also comprises a depth of field adjusting device; the depth of field adjusting device includes: and the adjustable pressing device is used for adjusting the depth of field height and is arranged at the position of the guide groove corresponding to the scanning window. The method comprises the following steps: a. providing an automatic paper feeder having an adjustable pressing device; b. feeding a pre-scanning object between the adjustable pressing device and the scanning window; c. adjusting the depth of field with an adjustable pressing device; d. scanning the pre-scanned object by using an image pickup unit and storing an image signal of the pre-scanned object; e. comparing the pre-scanned object image with a pre-stored image and determining an optimal depth of field; f. fixing the adjustable pressing device to the position with the optimal depth of field height. The invention can obtain the clearest image of the scanned object.

Description

Automatic paper feeding device and method for adjusting depth of field

(1) Technical field:

The invention relates to an automatic paper feeding device, in particular to an automatic paper feeding device for a scanner and a depth-of-field adjustment method thereof.

(two) background technology:

With the rapid development of high technology and the rapid development of microelectronics technology, computers have penetrated into every family and enterprise and become an indispensable electronic product in modern life. Due to the prevalence of computer multimedia, more peripheral products are needed as Input and output devices, which are also related to optoelectronic semiconductor technology, especially scanners, have become a must-have product in computer peripheral devices.

The scanner mainly uses a light source device to provide a light source to illuminate an object to be scanned, and then uses an optical path device to receive the image of the object to be scanned reflected by the light source device during scanning, and uses a charge-coupled device to pick up the image of the object to be scanned. The photoelectric signal is converted to form a digital signal, which is finally sent to the computer for image signal processing.

Please refer to FIG. 1A and FIG. 1B , which are schematic diagrams of a conventional flatbed scanner. It is mainly that an original supporting glass 12 is provided on the upper surface of the housing 11 of an optical scanner 1 to accommodate an object 80 to be scanned, and a power source group 13 is provided in the housing 11, which is connected to a transmission device 14, so that The power output by the power source group 13 can drive an image pickup unit 15 through the transmission device 14, so that the image pickup unit 15 can move linearly along the direction of the guide rod 16 in the hollow casing 11, so as to pick up the object to be scanned on the original supporting glass 12 80 image signal. The image pickup unit 15 has a hollow housing 151, a light source 152, which is positioned at an appropriate position on the upper surface of the housing 151, several reflective mirrors 153, a lens group 154 and a charge-coupled device 155; The light beam directed at the object to be scanned 80, after the reflected light enters the casing 151, is refracted by several reflective mirrors 153 to increase the optical path distance to an appropriate length, and is then focused by the lens group 154 to form an image on the charge-coupled on the element 155, and convert the scanned image data into electrical signals.

Please refer to FIG. 2A and FIG. 2B , which show a schematic diagram of a scanning device of an automatic document feeding device of a conventional flatbed scanner. When the flatbed scanner performs paper-feed scanning, an automatic paper feeder 2 is mounted on the flatbed scanner 1, and after the image pickup unit 15 is moved to the scanning section of the automatic paper feeder 2, the image pickup unit 15 is fixed , the automatic paper feeding device 2 is provided with a guide groove 21, and a scanning window 22 is provided at an appropriate position of the guide groove 21, and the scanning window 22 is used for the image pickup unit 15 to pick up the image signal of the object to be scanned 80 passing through the guide groove 21, the image signal It is produced by using the light source 152 to be reflected or transmitted by the object 80 to be scanned; wherein, after the reflected light enters the housing 151 of the image pickup unit 15, it is reflected by several reflective mirrors 153, and then focused by the lens group 154 to form an image on the charge-coupled device 155, and convert the scanned image data into electrical signals.

Please refer to FIG. 3A and FIG. 3B , which are side views of the objects to be scanned in the existing automatic paper feeding device. Since the automatic paper feeding device 2 is provided with a guide groove 21, it has an appropriate accommodating space for For objects 80 of various thicknesses to be scanned to pass through. When the thinner object to be scanned 80a is fed into the scanning window 22 with one feeding roller 23, the distance between the thinner object to be scanned 80a and the scanning window 22 is higher than that of the thicker object to be scanned 80b. When the depth of field height h' is long, it will cause an error in the optical path when the image pickup unit 15 (not shown in the figure) picks up the object 80 to be scanned, so that the object to be scanned that is imaged on the charge-coupled device (not shown in the figure) The image of the scanned object 80 is sometimes not clear enough.

(3) Contents of the invention:

The main purpose of the present invention is to provide an automatic paper feeding device with adjustable depth of field.

Another object of the present invention is to provide a method for adjusting the depth of field of an automatic paper feeding device that can adapt to different paper qualities.

To achieve the above object, the present invention takes the following technical measures:

An automatic paper feeding device of the present invention is provided with a guide groove for feeding documents to be scanned, and a scanning window for the image pickup unit to pick up the image of the object to be scanned is provided at a certain position of the guide groove; it also includes a depth of field adjustment device;

Depth of field adjustment devices include:

An adjustable pressing device for adjusting the height of the depth of field is arranged at a certain position of the guide groove corresponding to the scanning window.

A method for adjusting the depth of field of an automatic paper feeding device of the present invention comprises the following steps:

(a) Provide an automatic paper feeding device with an adjustable pressing device, the automatic paper feeding device has a guide groove for placing objects to be scanned, the guide groove is provided with a scanning window, and the adjustable pressing device is located on the guide The position corresponding to the scanning window on the slot;

(b) feeding a pre-scan object between said adjustable hold-down device and the scan window;

(c) adjusting the depth of field height with the adjustable pressing device;

(d) using the image pickup unit to scan the pre-scanned object and store its image signal;

(e) comparing the pre-scan object image with a pre-stored image, and determining an optimal depth of field height;

(f) Fix the adjustable pressing device to the optimal depth of field height position.

Compared with the prior art, the present invention has the following effects:

The above-mentioned device and method of the present invention can adjust the depth of field of the automatic paper feeding device to be suitable for various paper qualities, and can provide clearer scanning images.

(4) Description of drawings:

Figure 1A: A perspective view of an existing flatbed scanner.

Figure 1B: Side cutaway view of an existing flatbed scanner.

FIG. 2A : a three-dimensional schematic diagram of a scanning device in which a conventional flatbed scanner is combined with an automatic paper feeding device.

FIG. 2B : a schematic side view of a scanning device of a conventional flatbed scanner with an automatic document feeding device.

Figure 3A: A side view of a thin object to be scanned fed by an existing automatic document feeder.

Fig. 3B: A side view sectional view of feeding a thicker object to be scanned by an existing automatic document feeding device.

4A and 4B : schematic diagrams of an embodiment of a flatbed scanner configured with an automatic paper feeding device according to the present invention.

FIG. 5A is a schematic side view of the first embodiment of the depth-of-field adjusting device in the automatic paper feeding device of the present invention.

FIG. 5B is a schematic side view of the second embodiment of the depth-of-field adjusting device in the automatic paper feeding device of the present invention.

FIG. 5C : a schematic side view of the third embodiment of the depth-of-field adjusting device in the automatic paper feeding device of the present invention.

FIG. 5D is a schematic side view of the fourth embodiment of the depth-of-field adjusting device in the automatic paper feeding device of the present invention.

Fig. 6: A schematic diagram of an embodiment of the object to be scanned in the present invention.

Fig. 7: A flow chart of an embodiment of the method for adjusting the depth of field of the automatic paper feeding device of the present invention.

(5) Specific implementation methods

Structural features of the present invention are described in detail as follows in conjunction with accompanying drawing and embodiment:

The main feature of the present invention is that the depth of field adjustment device in the automatic paper feeding device is provided with an adjustable pressing device corresponding to a guide groove at an appropriate position of the scanning window, so as to use the adjustable pressing device to adjust the object to be scanned to pass through the scanning A depth-of-field height of the viewport.

Please refer to FIG. 4A and FIG. 4B , which are schematic diagrams of an embodiment of the automatic paper feeding device of the present invention. Wherein, the automatic paper feeding device 2 of the present invention is arranged on a flatbed scanner, and the automatic paper feeding device 2 is provided with a guide groove 21, and a scanning window 22 is opened at the appropriate position of the guide groove 21, and the guide groove 21 is opposite to each other. An adjustable pressing device 3 is provided at an appropriate position corresponding to the scanning window 2. When an object to be scanned 80 is placed, the guide groove 21 provides a feed-in roller 23 to screw the object to be scanned 80, so that the object to be scanned 80 When moving along the guide groove 21 at the scanning window 22, use the adjustable pressing device 3 to lightly press the object 80 to be scanned so that when it passes through the scanning window 22, the depth of field remains unchanged. After an image pickup unit 15 moves to the scanning section of the automatic document feeding device 2 , the image pickup unit 15 is fixed. The image pickup unit 15 provides a light source 152, and illuminates the object 80 to be scanned, and generates an image signal after reflection or transmission. After the reflected light enters the housing 151 of the image pickup unit 15, it is reflected and folded by several reflectors 53, After lengthening the optical path distance to an appropriate length, the lens group 154 focuses and forms an image on the charge-coupled device 155, and converts the data of the scanned image into an electrical signal, and then uses a feed-out roller 24 to rotate the object 80 to be scanned. out to release the guide groove 21.

As shown in Figure 5A to Figure 5D, it is a side view of an embodiment of the depth of field adjustment device in the automatic paper feeding device of the present invention, wherein the adjustable pressing device 3 includes: a power source 31, a transmission unit 32 and a Adjustment unit 33. In the embodiment of Fig. 5A and Fig. 5B, power source 31 comprises a motor 311, and it supplies output power, and motor 311 can provide the power of feed-out roller 24 simultaneously, so transmission unit 32 is to link with feed-out roller 24, and The transmission unit 32 includes a transmission belt 321 to properly transmit the power. The adjustment unit 33 cooperates with the transmission belt 321 and can be a cam 331 or an eccentric wheel 332. The transmission belt 321 transmits the power output by the power source 31 and can drive the cam 331. Or the eccentric wheel 332 rotates to form various angular positions corresponding to different lengths to change the depth of field h, so the depth of field h when the object 80 to be scanned passes through the scanning window 22 can be adjusted.

In another embodiment of the present invention, as shown in FIG. 5C , the power source 31 is an electric motor 311a that provides power alone, and can provide forward and reverse bidirectional rotation, and is different from the above-mentioned embodiment in that the feed-out roller 24 is used to connect In this embodiment, the transmission unit 32 includes a gear set 322, the adjustment unit 33 cooperates with the gear set 322 to form a rack 333, the gear set 322 transmits the power output by the power source 31, and can drive the rack 333 to generate linear displacement , to change the depth of field height h. In another embodiment of the present invention, as shown in FIG. 5D , wherein the transmission unit 32 includes a connecting rod group 323, the adjusting unit 33 cooperates with the connecting rod group 323 to form a slider 334, and the connecting rod group 323 transmits the power source 31 The output power converts the rotational displacement into a linear displacement of the slider 334 to change the height h of the depth of field. Certainly, the adjustment unit 33 and the transmission unit 32 above can be replaced with each other, and the deformation of this type of device can be understood and implemented according to the above description, so no more details are given here.

When scanning, the thickness of the fed object 80 to be scanned will affect the depth of field height h, causing the optical path error in the process of the image pickup unit 15 picking up the object 80 to be scanned. A pre-scanned object 81 with the same thickness as the scanned object 80 is used to fix the adjustable position of the adjustable pressing device 3 according to the pre-scanned object 81, and then scan the object 80 to be scanned.

As shown in FIG. 6, it is a schematic diagram of a pre-scan object 81 used in the present invention. Wherein, the pre-scanned object 81 is a calibration manuscript, which is provided with a pattern 82 that can provide a pick-up judgment signal. The pattern 82 can be a black and white stripe pattern, which can be designed to be parallel to a feeding direction 83 ( Or vertical) stripe pattern, of course, the pattern 82 can be set at the central part of the feeding front end of the pre-scanning object 81, and can also be located at other positions, as long as the image pickup unit (not shown in the figure) is available when the pre-scanning object 81 is feeding. Shown) to pick up the image of pattern 82.

Please refer to FIG. 7 , which is a flow chart of an embodiment of the method for adjusting the depth of field of the automatic paper feeding device of the present invention. The depth of field adjustment method of the automatic paper feeding device of the present invention comprises the following steps:

Step 51: Provide an automatic paper feeding device with an adjustable pressing device, the automatic paper feeding device is provided with a guide groove, and the guide groove is provided with a scanning window for providing an image pickup unit for image pickup, and the pressure can be adjusted The control device is located on the guide groove corresponding to the scanning window.

Step 52: When scanning, a pre-scanned object with the same thickness as the object to be scanned needs to be fed in first, so that the pre-scanned object is fed along its guide groove and can be located between the scanning window and the adjustable pressing device, wherein , the pre-scanned object is a corrected draft, and the corrected draft is provided with a pattern of black and white stripe patterns that can provide picking judgment.

Step 53: Using an adjustable pressing device to adjust and change the depth of field h when the pre-scanned object passes through the scanning window.

Step 54: Use the image pickup unit to pick up the image of the pre-scanned object. The image pickup unit picks up the pattern image on the pre-scanned object, and then converts the data of the scanned pre-scanned object image processed by the image pickup unit into electrical signals. be stored.

Step 55: Comparing the image of the pre-scanned object with the pre-stored image, the image data of the pre-scanned object that is most similar to the pre-stored image can be compared to determine an optimal depth of field.

Step 56: Adjust the adjustable pressing device to the optimum depth of field height where the pre-scanned object passes through the scanning window, and fix the adjustable pressing device. If it is determined that the depth-of-field height position is not optimal, then step 53 to step 55 are repeated.

Step 57: Rotate the scanned object out with the feed-out roller to release the guide groove to feed out the pre-scanned object, and then scan the to-be-scanned object with the same thickness.

The above content is to use the embodiment to illustrate the technical characteristics of the present invention, and is not used to limit the protection scope of the present invention. Even if someone makes a slight change on the basis of the concept of the present invention, it should still belong to the protection scope of the present invention.

Claims (8)

1. An automatic paper feeding device, which is provided with a guide groove for feeding the documents to be scanned, and a certain position of the guide groove is provided with a scanning window for the image pickup unit to pick up the image of the object to be scanned; it is characterized in that Including a depth of field adjustment device; Depth of field adjustment devices include: An adjustable pressing device for adjusting the height of the depth of field is arranged at a certain position of the guide groove corresponding to the scanning window. 2. The automatic paper feeding device according to claim 1, wherein the adjustable pressing device comprises: a power source available for output power; a transmission unit capable of transmitting power, which is connected to the power source; An adjusting unit is connected with the transmission unit, so as to adjust the height of the depth of field by using the displacement of the adjusting unit. 3. The automatic paper feeding device according to claim 2, characterized in that: The power source is an electric motor; The transmission unit is a transmission belt; The adjustment unit is an eccentric wheel driven by a transmission belt. 4. A method for adjusting the depth of field of the automatic paper feeding device according to claims 1 to 3, comprising the following steps: (a) Provide an automatic paper feeding device with an adjustable pressing device, the automatic paper feeding device has a guide groove for placing objects to be scanned, the guide groove is provided with a scanning window, and the adjustable pressing device is located on the guide The position corresponding to the scanning window on the slot; (b) feeding a pre-scanned object having the same thickness as the object to be scanned, and placing it between the adjustable pressing device and the scanning window; (c) Adjust the height of the depth of field with an adjustable pressing device; (d) using the image pickup unit to scan the pre-scanned object and store its image signal; (e) comparing the pre-scan object image with a pre-stored image, and determining an optimal depth of field height; (f) Fix the adjustable pressing device to the optimal depth of field height position. 5 . The method for adjusting the depth of field of the automatic paper feeding device according to claim 4 , wherein the pre-scanned object is a corrected draft, and the corrected draft is provided with patterns that can be picked up and judged. 6. The method for adjusting the depth of field of the automatic paper feeding device according to claim 5, wherein the pattern is a black and white stripe pattern. 7. The method for adjusting the depth of field of the automatic paper feeding device according to claim 5, wherein in the step (d), the image signal picked up and stored by the image pickup unit is the pattern image on the pre-scanned object. 8. The method for adjusting the depth of field of the automatic paper feeding device according to claim 4, further comprising the following steps after the step (f): (g) Feed out the pre-scan.

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