JP5796615B2 - Image input device - Google Patents

Description

  The present invention relates to an image input device.

  Various techniques related to the image input apparatus are known (for example, see Patent Document 1).

  For example, Patent Document 1 stores an illumination unit that emits illumination light that illuminates a document, an imaging unit that captures an image of a document illuminated by the illumination unit, and an imaging unit, and the document is placed on the upper surface. There is described an image input device having a casing having a document table and an optical system for guiding an image of the document to an imaging unit. More specifically, the document table of the image input apparatus is formed with a flat portion and a raised portion. In this way, depending on the image input device, it becomes possible to prevent the illumination light totally reflected on the document from entering the imaging unit, so that a clear image in which the illumination light is not directly reflected can be obtained. Can do.

  Further, for example, Patent Document 2 describes a document input device that prevents reflection when a document document or the like is captured. More specifically, the document input device includes an imaging unit that images a document. The document input device includes a document table having a placement surface on which a document is placed. The document input device includes a support member that is rotatably attached to the document table and that rotatably supports the imaging unit. The document input device includes an illumination device that is built in the support member and that illuminates the document placed on the placement surface. The document input device captures an image of the document placed on the placement surface by adjusting the rotation angle position of the support member with respect to the document table and the rotation angle position of the image pickup unit with respect to the support member. It is possible to prevent the lighting device from being reflected. Thus, depending on the document input device, the device can be reduced in size, simplified, reduced in cost, improved in operability, and the like.

  For example, Patent Document 3 describes an image input device including a light source that emits light that illuminates a document, and an imaging unit that captures an image of the document that is illuminated with light. More specifically, the image input apparatus includes a reflection preventing member including a transparent sheet which is subjected to a process for diffusing light or preventing reflection of light on at least one surface and used to overlap the surface of the document. . In this way, depending on the image input device, the reflection of the light source onto the document can be easily prevented, and the device can be downsized.

  Further, for example, Patent Document 4 describes a digital camera that can detect a region where a reflection occurs in an image related to a subject. More specifically, this digital camera acquires an image relating to a subject. And this digital camera detects the reflection area | region where the reflection has arisen among the images. And this digital camera sets the detected reflection area | region among 1st images as a to-be-replaced image part. Then, the digital camera extracts a replacement image portion that corresponds to the part of the subject appearing in the replacement image portion and is not detected as a reflection region in the second image. The digital camera replaces the replacement image portion in the first image based on the extracted replacement image portion. In this way, depending on the digital camera, it is possible to remove the reflection easily and quickly.

  Further, for example, Patent Document 5 discloses an inspection device that can confirm the presence of a watermark or the like on a paper medium that has been subjected to a watermark or special printing, such as a bill or traveler's check, and can prevent the use of a counterfeit bill or the like. Is described. More specifically, this inspection apparatus has a main body in which a gap into which a paper medium such as a bill is inserted is formed. In addition, this inspection apparatus has a gripping part for gripping a paper medium in the gap. In addition, this inspection apparatus has a fixing means for allowing the main body to stand up so that a paper medium can be inserted into the gap from above. The inspection apparatus includes a light emitting unit that is provided on the back surface of the gripping unit and that irradiates the paper medium gripped by the gripping unit. The inspection apparatus also includes a switch unit that detects a paper medium inserted in the gap and causes the light emitting unit to emit light based on the detection result. The main body is an internal hollow casing. The gripping portion is a transparent plate that is rotatably mounted by a transparent plate that covers the hollow opening inside the main body and a shaft portion in the lower portion of the gap, and is urged to be pressed against the transparent plate. It is comprised by the member. In this way, depending on this inspection device, there is no discomfort to customers even in face-to-face sales without registers, such as stalls and outdoor sales, and night sales in taxis and outdoor fields such as stalls. The presence of a watermark or the like can be confirmed and a counterfeit bill can be found efficiently without causing any trouble in the bill delivery operation.

  For example, Patent Document 6 describes a stand-type image reading apparatus that reads a document without closely contacting an image pickup unit. More specifically, this image reading apparatus comprises a document plate on which a document is placed, a placement plate on which the document is placed, and a deterrent plate for shielding light from the outside. An anti-reflection plate that is detachable from the original table and prevents the light from being reflected from the surface of the original placed on the original table and entering the imaging unit is provided. In this way, depending on the image reading apparatus, there is no need to find the document placement position where the so-called shine phenomenon does not occur on the glossy surface of the document.

  Further, for example, Patent Document 7 describes an image reading apparatus that captures an image of a subject placed on a placement unit using an imaging unit such as a camera. More specifically, the image reading apparatus includes an imaging unit that can image a subject. Further, this image reading apparatus is outside the range of the reflected image imaging range in which the imaging unit can capture the subject and at least the reflected image of the imaging unit reflected by the subject is reflected when the subject is captured by the imaging unit. In addition, a mounting unit for mounting the subject inclined with respect to the optical axis of the imaging unit until the imaging unit is positioned. Further, the image reading apparatus is made of a material having a high light diffusibility or a material having a high light absorption property, and includes a diffusing member that connects the image pickup unit and the placement unit and is disposed in the reflection image pickup range. Prepare. In addition, the image reading apparatus has an opening portion in which a predetermined range on the side of the mounting portion on the diffusing member where the inclination of the mounting portion is high is open to the mounting portion, and a subject can be placed on and removed from the mounting portion. Is provided. In this way, clear image information can be obtained more reliably depending on the image reading apparatus.

  For example, Patent Document 8 describes an image processing apparatus that processes an image obtained by reading a document such as a book. More specifically, the image processing apparatus includes a first photographed image in which a document is photographed and a second photographed image in which a shadow of an object moved by the user across the document is reflected on the document. get. The image processing apparatus sets a whiteout region based on the first captured image. Then, the image processing apparatus extracts a shadow area image in the whiteout area from the second captured image, and performs a whiteout correction process for synthesizing the shadow area image with the first captured image. In this way, depending on the image processing apparatus, it is possible to acquire an image without whiteout due to reflection of illumination light.

Japanese Patent Laid-Open No. 10-200792 Japanese Patent Laid-Open No. 11-187214 JP 2003-15238 A Japanese Patent No. 3758655 Japanese Patent No. 3722828 Japanese Patent No. 4756378 Japanese Patent No. 4898646 JP 2012-175166 A

  By the way, there is a type of image input device that captures an image of a document by an image input unit provided above the document placed horizontally. Depending on such an image input device, when a glossy document is imaged under ceiling illumination, light reflected from the illumination light without being diffused is incident on the image input unit. Jumping may occur.

  These problems cannot be solved by the inventions described in Patent Documents 1 to 8. The objective of this invention is providing the image input device which solves the subject mentioned above.

  In order to solve the above-described problems, according to a first aspect of the present invention, there is provided an image input device, an image input unit that captures an image of a document and inputs the image, and an image input unit that is inclined with respect to the optical axis of the image input unit. And a document surface that is formed of a transparent material that transmits light, and is opposed to the document table on which the document is placed on the document surface, inclined with respect to the optical axis of the image input unit. And a reflecting mirror having a mirror surface facing the surface opposite to the placement surface of the document table so that the light transmitted through the document placed on the placement surface is reflected to the image input unit.

  It should be noted that the above summary of the invention does not enumerate all the necessary features of the present invention. Also, a sub-combination of these feature groups can also be an invention.

  As is apparent from the above description, according to the present invention, an appropriate image without whiteout can be acquired even when a glossy document is imaged under illumination provided on the ceiling.

It is a figure which shows an example of the form of the image input device 100 which concerns on 1st Embodiment. 2 is a diagram illustrating an example of a use environment of the image input apparatus 100. FIG. It is a figure which shows an example of the form of the principal part of the image input device 100 which concerns on 2nd Embodiment. It is a figure which shows an example of the relationship between the angle of the mounting surface 121, and the angle of the reflective mirror 150. It is a figure which shows an example of the form of the image input device 100 which concerns on 3rd Embodiment. It is a figure which shows an example of the form of the principal part of the image input device 100 which concerns on 3rd Embodiment. It is a figure which shows an example of the form of the principal part of the image input device 100 which concerns on 3rd Embodiment. It is a figure which shows an example of the relationship between the angle of the mounting surface 121, and the angle of the reflective mirror 150.

  Hereinafter, the present invention will be described through embodiments of the invention. However, the following embodiments do not limit the claimed invention, and all combinations of features described in the embodiments are described below. However, this is not always essential for the solution of the invention.

  FIG. 1 shows an example of an image input apparatus 100 according to the first embodiment. The image input device 100 is a machine that captures a document C. In this embodiment, a case where a glossy card is photographed as the document C will be described as an example.

  The image input apparatus 100 includes a support plate 110, a document table 120, a stand 130, and an image input unit 140.

  The support plate 110 is a plate-like member that supports the document table 120 and the stand 130. For example, the support plate 110 is provided with a member for supporting the document table 120 and a member for supporting the stand 130.

  The document table 120 is a member for placing the document C on the placement surface 121. The mounting surface 121 is inclined and opposed to the optical axis of the image input unit 140. For example, the mounting surface 121 is arranged to be inclined with respect to the optical axis of the image input unit 140 by being disposed so that the angle between the mounting surface 121 and the support plate 110 is an angle α.

  The stand 130 is a member that supports the image input unit 140 at a predetermined height from the document table 120. For example, the stand 130 is supported by the placement surface 121.

  The image input unit 140 is an apparatus that captures an image of the original C and inputs an image. For example, the image input unit 140 includes a lens and an image sensor. The light reflected by the placement surface 121 of the document table 120 is imaged on the image sensor via the lens. The image formed on the image sensor is converted into image data by photoelectric conversion. Then, the image input unit 140 outputs the image data to the computer P. Here, the computer P is an apparatus that performs image processing on image data.

  FIG. 2 shows an example of the usage environment of the image input apparatus 100. In the present embodiment, an example in which the image input apparatus 100 is used in an environment in which an illumination L is provided on a ceiling T will be described. In such an environment, when the light emitted from the illumination L is applied to the document C placed on the placement surface 121 of the document table 120, the light is directed in the direction of the reflection angle θ2 that is the same as the incident angle θ1. Reflects as strong reflected light. Also, some light is reflected as weak diffused light in various directions without having a specific direction. When the original C has a color that easily absorbs light, part of the light is absorbed by the original C.

  For example, when strong reflected light among the reflected light is incident on the image input unit 140, the obtained image may be overexposed. In the image input apparatus 100 according to the present embodiment, since the document C is placed on the inclined placement surface 121 of the document table 120, strong reflected light does not enter the image input unit 140 and weak diffusion is performed. Since light enters, whiteout does not occur in the obtained image.

  FIG. 3 shows an example of a configuration of a main part of the image input apparatus 100 according to the second embodiment. The image input apparatus 100 of this embodiment further includes a reflecting mirror 150.

  The reflecting mirror 150 is provided to be inclined and opposed to the optical axis of the image input unit 140 at an angle different from the placement surface 121 of the document table 120, and the document C placed on the document table 120. The light reflected at is further reflected to the image input unit 140.

  In order to prevent the light source of the illumination L that causes regular reflection among the reflected light, as shown in FIG. Only the size necessary for providing an image to the unit 140 is provided. Usually, since the image input unit 140 is smaller than the document C, the reflecting mirror 150 is smaller than the size of the document C. It should be noted that the range of the illumination L that causes regular reflection according to the present invention is blocked by the reflecting mirror 150 and becomes only the ranges A and B. For this reason, diffuse light, not total reflection light, is the main light reflected from the original C entering the image input unit 140 from the original C. Therefore, there is little occurrence of whiteout.

  FIG. 5 shows a third embodiment. The inclined document table 120 of the present embodiment is formed of a transparent material that transmits light. As shown in FIG. 6, since the document table 120 is transmitted, the image on the back side of the document C is reflected by the reflecting mirror 150 and the image is input to the image input unit 140.

  Further, since the document table 120 is transparent, as shown in FIG. 7, an image obtained by irradiating light from the back side and watermarking the document C with light like the document C placed on the document table 120 is input. Can do.

As shown in FIG. 8, the distance from the center of the inclination angle between the document table 120 and the reflecting mirror 150 to the document C is M, the length from the upper end to the lower end of the document C is N, and the document table 120 is inclined with respect to the horizontal plane. Is set to be α, and the inclination of the reflecting mirror 150 with respect to the horizontal plane is β, M × tan (β) = N / tan (2 × β) and γ = β = α / 2.

  In this embodiment, the reflected light from the document table 120 is reflected by the reflecting mirror 150 to irradiate the image input unit 140 with the reflected light. When the document C is projected on the image input unit 140, the rectangular document C becomes rectangular, and the focal length of the document C is constant from the surface of the document C, so that the document C is projected on the image sensor without blurring. However, since it is a mirror image by the reflecting mirror 150, conversion to return the mirror image is required.

  In this way, light from the back side of the image of the original C can be transmitted, and light that has passed through a watermark or the like can be input to the image input unit 140.

  Further, if the document table 120 is made detachable, it can also input a paper-type document C that does not cause normal reflection.

  According to this embodiment, when the document C having a glossy surface is converted into electronic data by the image input device 100, the use of the illumination L of the ceiling T that is generally provided is not changed. Appropriate images can be acquired by eliminating reflections. At this time, the image input unit 140 is not moved, the original platen 120 is not moved, and the original C is set on the original platen 120, and the image is captured by an operation using a normal stand-type image input. You can get images without.

  Further, by changing the use of the illumination L on the ceiling T without changing the use of the illumination L on the ceiling T, a watermark pattern such as a banknote is also converted into electronic data by a normal operation of the image input apparatus 100. it can.

  Further, since the document table 120 is detachable, it is not glossy, and when it is not necessary to input a watermark, it can be removed from the field of view of the image input unit 140. An image can be input even for a document C having no image without changing the apparatus.

  As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. It will be apparent to those skilled in the art that various modifications or improvements can be added to the above embodiment. It is apparent from the scope of the claims that the embodiments added with such changes or improvements can be included in the technical scope of the present invention.

  The execution order of each process such as operations, procedures, steps, and stages in the system, method, apparatus, program, and recording medium shown in the claims, the description, and the drawings is particularly “before” and “prior to It should be noted that it can be realized in any order unless the output of the previous process is used in the subsequent process. Regarding the operation flow in the claims, the description, and the drawings, even if it is described using “first”, “next”, etc. for the sake of convenience, it means that it is essential to carry out in this order. is not.

DESCRIPTION OF SYMBOLS 100 Image input device 110 Support plate 120 Document stand 121 Placement surface 130 Stand 140 Image input part 150 Reflector C Document L Illumination P Computer

Claims (2)

An image input unit for capturing an image of a document and inputting the image;
An original table on which the original is placed on the mounting surface, comprising a mounting surface that is inclined and opposed to the optical axis of the image input unit and is formed of a transparent material that transmits light;
A document mounting surface of the document table so as to be inclined and opposed to the optical axis of the image input unit and to reflect light transmitted through the document mounted on the mounting surface to the image input unit; Is a reflection mirror having a mirror surface facing the opposite surface. The image input apparatus according to claim 1, wherein the document table is detachably provided.

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