JP3231838B2 - Image reading device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is capable of reading a transparent original such as a reflective original or a film with high accuracy by a single apparatus, and the reading density and reading area of each original can be adjusted to a commonly used original. The present invention relates to an image reading apparatus that can be conveniently set together.

[0002]

2. Description of the Related Art There have hitherto been proposed many image reading apparatuses capable of selecting a mode for reading a reflection original and a mode for reading a transparent original such as a film. A film projector is used to project and form a film image on the original reading table surface, and one reflection and transmission original that can select between a mode for reading the projected image and a mode for reading the original placed on the original surface. For example, there is an image reading apparatus that can be read by using the image reading apparatus disclosed in Japanese Patent Application Laid-Open No. 2-174462 under the title of "image reading apparatus". In this case, a mode in which the document placed on the document reading table is scanned by the reading optical system and read, and a film image is projected and formed on the document surface by a film projector, and the projected image is transmitted to the reading optical system. In a device provided with a selection mode in which a reading mode can be selected, in the film reading mode, the reading optical system is stopped in the scanning direction, and reading scanning is performed by moving the film. Accordingly, in the film reading mode, since the scanning is performed by moving the film while the reading optical system is fixed, the projection optical system includes a projection lens and a mirror as compared with a conventional apparatus that projects and reads the entire surface of the film at once. The optical system can be made compact, and only the slit-shaped region needs to be illuminated, so that the illumination system can be made compact.

[0003] In addition, a reflection and transmission type in which a mode in which a transparent original such as a film is read by illuminating the original from the side opposite to the imaging lens or the image sensor and a mode in which an original placed on the original surface is read can be selected. With respect to an image reading apparatus capable of reading an original on a single device, for example, Japanese Patent Application Laid-Open No. 3-46864 discloses an "image reading apparatus", Japanese Patent Application Laid-Open No. 3-55961, an "image reading apparatus", and Japanese Patent Application Laid-Open No. 3-58566. Under the title of "image reading device".

Japanese Patent Application Laid-Open No. 3-46864 discloses an "image reading apparatus" which scans an original placed on an original platen by a scanning optical system and reads a transparent original such as a film. It is possible to attach a device that illuminates the original from the side opposite to the image forming lens and image sensor, and to move the image forming lens in the reading optical system so that a transparent original such as a film can be enlarged and read. It was done. As a result, a mode for reading a reflection original and a mode for reading a transmission original can be selected, and a transmission original such as a film can be read with high accuracy.

Japanese Patent Application Laid-Open No. 3-55961 discloses an "image reading apparatus" which scans a document placed on a document table and reads the document.
A document table is provided for moving a transparent document such as a film across an optical path between an image forming lens of a reading optical system and a document surface. As a result, a mode for reading a reflection original and a mode for reading a transmission original can be selected, and the distance between the transmission original and the imaging lens can be shortened. High-precision reading can be performed.

In the "image reading apparatus" disclosed in Japanese Patent Application Laid-Open No. 3-58566, when reading an original such as a reflection original or a film with a single image reading apparatus, separate light sources and an original reading base are used for reflection reading and transmission reading. A mode in which a document placed on a document reading table is read by scanning an optical system,
A reading mode in which a transparent original such as a film is moved so as to cross the optical path between the image forming lens of the reading optical system and the original surface. Here, when reading a transparent original, one of the reflection mirrors of the reading optical system is movable. As a result, a mode for reading a reflective original and a mode for reading a transparent original can be selected, and the distance between the transparent original and the imaging lens is shortened. Reading can be performed.

Further, the applicant has filed an application having the following contents. First, as a first example, there is an application filed in Japanese Patent Application No. 3-182820 under the title of "document reading device". In this method, a mode for reading a reflection original and a mode for reading a transmission original such as a film can be selected. A separate light source and a document table are provided for the reflection reading and the transmission reading. In an apparatus having an optical system that also serves as a moving unit and forms an image on different photoelectric conversion elements with different imaging lenses, image signals from different photoelectric conversion elements read by a common sub-scanning system are electrically combined. Things. As a result, a combined image of the reflection document and the transmission document can be obtained with a simple configuration.

As a second example, Japanese Patent Application No. Hei 4-336
There is an application filed in Japanese Patent Publication No. 16 under the title of "image reading apparatus". This allows the user to select between a mode for reading a reflection original and a mode for reading a transmission original, and separate light sources in the reflection reading optical system and the transmission original reading optical system, respectively.
In an apparatus having a document table, a document table for reading a transparent document is fixed to a first or second traveling body for reading a reflected document. Accordingly, the sub-scanning traveling system of the reflection original reading optical system and the transmission original reading optical system can be shared, so that the size of the entire apparatus can be reduced and the cost of the apparatus can be reduced. Further, in particular, by fixing the original platen for reading the transparent original on the second traveling body for reading the reflective original, it is possible to narrow the control range of the speed required for the common sub-scanning traveling system. Becomes

[0009]

SUMMARY OF THE INVENTION As described above,
174462, JP-A-3-46864, JP-A-35
5961, JP-A-3-58566, Japanese Patent Application 4-33
No. 616 describes that both reflection and transmission documents can be read by one apparatus, but in any case, both reflection and transmission documents cannot be read at the same time.

In the case of the apparatus disclosed in Japanese Patent Application No. 3-182820, a single apparatus can simultaneously read reflected and transmitted documents, but two photoelectric conversion elements are provided for reading each document. Therefore, a plurality of these signal processing systems are required, and memories for reflection and transmission are separately required. In addition, the entire apparatus becomes expensive.

[0011]

According to the first aspect of the present invention, a mode for reading a reflected original and a mode for reading a transparent original such as a film can be selected. An optical system, a light source for reading the transparent document, a transparent document reading optical system having a document table, by forming an image on the same photoelectric conversion element by different imaging lenses, the reflection document or the transparent document In the image reading apparatus capable of reading, a half mirror is installed at a position where an optical path of the reflection original reading optical system and an optical path of the transmission original reading optical system intersect, and the half mirror on the optical path synthesized by the half mirror is provided. reflective original and the transparent original is placed the photoelectric conversion element in a position for imaging simultaneously, the reflective original or of the transparent original Sukunakutomoi not a Re or the other Between the draft and the light source for illuminating the original, it is disposed an original light shielding plate for shielding the light emitted from the light source in at least part of the document.

According to a second aspect of the present invention, in the first aspect of the invention, the document light shielding plate is formed such that there is a boundary of light shielding of the document illumination light in the sub-scanning direction of document reading.

According to the third aspect of the present invention, the first or second aspect is provided.
In the invention described above, at least one of the imaging lenses for reading the reflection original or the transmission original is formed on the zoom lens.

According to a fourth aspect of the present invention, in the first, second or third aspect of the present invention, the half mirror disposed at a position where the optical path of the reflection original reading optical system and the optical path of the transmission original reading optical system intersect with each other. A half-mirror light-shielding plate is provided around the periphery.

[0015]

According to the first aspect of the present invention, illumination light from a light source corresponding to at least a part of at least one of the reflection and transmission documents is shielded by the document light-shielding plate, so that both documents are reflected. A complicated operation of reading and synthesizing into separate memories becomes unnecessary.

According to a second aspect of the present invention, the original light shielding plate of the first aspect of the present invention is formed so as to have a boundary between light shielding of the original illumination light in the sub-scanning direction of the original reading. The troublesome operation of reading and synthesizing in separate memories is not required.

According to the third aspect of the present invention, by forming at least one of the image forming elements on a zoom lens, it is possible to read a reflected or transmitted original by zooming at different magnifications.

According to the fourth aspect of the present invention, since the half-mirror light-shielding plate is disposed around the half-mirror, light that has passed through the half-mirror and is not directed toward the photoelectric conversion element does not illuminate the reflection original again. It is possible to do.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows a reflection original reading optical system 5 having a light source 3 for reading the reflection original 1 and a contact glass 4 as an original table, in which a mode for reading the reflection original 1 and a mode for reading the transparent original 2 such as a film can be selected. And a light source 6 for reading the transparent document 2 and a transparent document reading optical system 8 having a contact glass 7 as a document table. The same photoelectric conversion element 11 is formed by different imaging lenses 9 and 10 from each other.
1 shows an arrangement of an image reading apparatus capable of reading the reflection original 1 or the transmission original 2 by forming an image on the original. System.

Here, the overall configuration of the present apparatus will be described. On the upper surface of the contact glass 4, there is provided a document light-shielding plate 12 for blocking illumination light from the light source 3 to the document, and on the upper portion of the document light-shielding plate 12, the reflection document 1 for reading is placed. ing. The reflected light from the reflection original 1 illuminated by the light source 3 is reflected by the reflection mirrors 13, 14, 15 constituting the reflection original reading optical system 5,
The light sequentially passes through a zoom lens 9 as an image forming lens and a half mirror 16, whereby an image is formed on a surface of a photoelectric conversion element (for example, a CCD sensor) 11 and detected. The photoelectric conversion element 11 is fixed to an electrical system circuit board 17 for performing an electrical reading process of the detected signal. In this case, the half mirror 16 is fixed at a position making an angle of 45 ° with the optical axis for reading the reflected original.

On the other hand, on the left side of the reflection original reading optical system 5,
A transparent original reading optical system 8 is provided. The transparent original 2 such as a film is placed on the contact glass 7.
A document light-shielding plate 18 for blocking the illumination light from the light source 6 that illuminates the transparent document 2 is placed above the transparent document 2. The light emitted from the light source 6 is reflected by the reflector 19.
Is reflected and condensed, is reflected by the mirror 20, and is diffused by the diffusion plate 21, whereby uniform illumination is provided on the surface of the transmission original 2. The transmitted light of the transmission original 2 is reflected by the reflection mirror 22, transmitted through the zoom lens 10 as an imaging lens, reflected by the reflection mirror 23, and guided to the half mirror 16. And this half mirror 1
The light is reflected by 6 and forms an image on the photoelectric conversion element 11 and is detected.

In such a configuration, at the time of reading a reflection original, the first traveling body 24 on which the reflection mirror 13 and the light source 3 are mounted and the second traveling body (not shown) on which the reflection mirrors 14 and 15 are mounted are two-to-one. By moving at the speed, the entire surface of the reflection original 1 is read. And the subsequent processing is
Following the optical path of the reflection original reading optical system 5 as described above, the light passes through the half mirror 16 and is detected by the photoelectric conversion element 11. On the other hand, when reading the transparent original, the transparent original 2 and the contact glass 7 are driven in the arrow direction Y (sub-scanning direction), whereby the entire surface of the transparent original 2 is read. At this time, the driving method of the sub-scanning traveling system for reading the reflection and transmission documents is, for example, a direct drive using a linear motor or a rotation to linear conversion using a rotation motor and a transmission system for converting rotation to linear. A drive system or the like can be used. The subsequent processing follows the transparent original reading optical system 8 as described above, and is reflected by the half mirror 16 and detected by the photoelectric conversion element 11.

Next, was disposed a reflective original reading optical system 5 of the optical path between the transparent original reading half mirror for the light shielding plate 28 around the half-mirror 16 and the optical path is located where the optical system 8, The reason why the half-mirror light-shielding plate 28 is provided is that the transmission component of the reflected light from the reflection mirror 23 in the reading of the transmission original in the half mirror 16 and the reflection of the reflection light from the reflection mirror 15 in the reading of the reflection original 15 are used. This is to eliminate the possibility that the reflection component of the light source illuminates the reflection original 1 again and degrades the reading accuracy.

As described above, the reflection original 1 and the transmission original 2
Are scanned by separate optical systems to form an image on the same photoelectric conversion element 11 via the half mirror 16, so that the reflection original 1 and the transmission original 2 can be read at the same time and in a combined form as an image. it can. Further, since the zoom lenses 9 and 10 are used, enlargement and reduction by an arbitrary optical system are possible. However, the imaging lens does not necessarily have to be a zoom lens.

Next, the operation of the document light shielding plates 12 and 18 will be described with reference to FIGS. FIG. 1A shows a document light-shielding plate 12 for blocking illumination light from the light source 3 for reading the reflection document 1 to the reflection document 1.
(B) shows a document light-shielding plate 18 for blocking illumination light from the light source unit (light source 6) for reading the transparent document 2 onto the transparent document 2. The document light shielding plates 12 and 18 of (a) and (b) are made of a transparent material (for example, transparent cellophane), and a non-transparent material (for example, black Paper) is adhered or installed. At this time, the arrangement relationship of the document, the non-transparent part portion of the reflective original 1 corresponding to the portion of the transparent original 2 corresponding to the transparent portions of the original light shielding plate 18 of the original light shielding plate 12, the original
The portion of the reflection document 1 corresponding to the transparent portion of the light shielding plate 12 corresponds to the portion of the transparent document 2 corresponding to the non-transparent portion of the document light shielding plate 18, respectively.

In this case, when the reflection original 1 and the transmission original 2 are read simultaneously, the reflection original 1
The transparent original 2 and the imaging position of both the document when reading simultaneously separated and, (c), the light-shielding original portion of the reflective original 1 corresponding to the non-transparent portion of the original light shielding plate 12 Board 1
8 are formed in such a manner that the portion of the transparent document 2 corresponding to the transparent portion 8 is fitted.
Therefore, from such a situation, the reflection original 1 and the transmission original 2
(In this case, when the fitting is performed as shown in (c)), the two originals are separately read into the memory, and
Then, the troublesome operation of combining is not required. Therefore, by providing the document light shielding plates 12 and 18, the image forming positions on the photoelectric conversion element 11 when reading both the reflection and transmission documents at the same time are separated, and the subsequent work is made more efficient and memory is saved. Can be achieved.

Next, in the document light shielding plates 12 and 18,
The reason for forming the boundary 26 for shielding the original illumination light along the sub-scanning direction Y (main scanning direction X) of the original reading will be described with reference to FIGS. (A) shows a document light-shielding plate 12 for blocking illumination light from the light source 3 for reading the reflective document 1 to the reflective document 1, and (b) shows a light source unit (light source 6) for reading the transparent document 2. original light shielding plate 18 for shielding the illumination light to the transparent original 2 from)
It shows. (A) and (b) the document light shielding plate 12,
Reference numeral 18 denotes a transparent material (for example, transparent cellophane), and a hatched portion is made of a non-transparent material (for example, black paper) so that there is a light-shielding boundary in the sub-scanning direction Y of the document. Adhered or installed. In this case, part of the reflective original 1 corresponding to the non-transparent portion of the document for <br/> light shielding plate 12, the portion of the transparent original 2 corresponding to the transparent portions of the original light shielding plate 18, the original light shielding plate The portions of the reflection document 1 corresponding to the 12 transparent portions correspond to the portions of the transmission document 2 corresponding to the non-transparent portions of the document light shielding plate 18, respectively.

When the reflection original 1 and the transmission original 2 are read at the same time, the image forming positions of both the originals when the reflection original 1 and the transmission original 2 are simultaneously read on the photoelectric conversion element 11 are separated. As shown in c), the portion of the transparent document 2 corresponding to the transparent portion of the document light shielding plate 18 is fitted into the portion of the reflective document 1 corresponding to the non-transparent portion of the document light shielding plate 12. The two originals are combined to form one image 27. For this reason, when the reflection original 1 and the transmission original 2 are combined (in the case where either the length or width of the original is long or the combination is performed), the two originals are read into separate memories and then combined. This eliminates the need for complicated operations.
Therefore, by forming the boundary 26 along the sub-scanning direction Y, as in the case described above, the image forming position on the photoelectric conversion element 11 when reading both the reflection and transmission originals at the same time is separated. It is possible to improve the efficiency of the operation and save the memory.

Although the hatched portions are non-transparent portions, conversely, the hatched portions may be transparent portions. The non-transparent portion of the document light-shielding plate 12 for reading the reflection document and the transparent portion of the document light-shielding plate 18 for reading the transparent document do not completely correspond to each other. There may be many parts. The document light shielding plate 18 for reading the transparent document is provided with a light source unit for light transmission (the light source 6).
Etc.) and the transparent original 2, but also between the transparent original 2 and the transparent contact glass 7, or on the side opposite to the transparent original 2 of the transparent contact glass 7.

Next, was disposed a reflective original reading optical system 5 of the optical path between the transparent original reading half mirror for the light shielding plate 28 around the half-mirror 16 and the optical path is located where the optical system 8, The reason why the half-mirror light-shielding plate 28 is provided is that the transmission component of the reflected light from the reflection mirror 23 in the reading of the transmission original in the half mirror 16 and the reflection of the reflection light from the reflection mirror 15 in the reading of the reflection original 15 are used. This is to eliminate the possibility that the reflection component of the light source illuminates the reflection original 1 again and degrades the reading accuracy.

Next, a second embodiment of the present invention will be described with reference to FIG. The description of the same parts as in the first embodiment (see FIG. 1) is omitted, and the same reference numerals are used for the same parts.

In this embodiment, the sub-scanning optical system for reflection and transmission reading is shared. That is, in the configuration of FIG. 1 described above, the sub-scanning traveling systems for reading the reflection original and for reading the transmission original are separate driving systems, however, here, the contact glass 7 for reading the transmission original is a reflection original. The sub-scanning first traveling body 29 is newly configured by being fixed to the first traveling body 24 for reading. Thus, the traveling body for reading the transparent document, which is required in the first embodiment, can be omitted, so that the size and cost of the apparatus can be reduced.

At the time of reading a transparent original, the first
The sub-scanning traveling system for reading the reflection original is driven so that the moving speed of the traveling body 29 becomes the speed at the time of reading the transmission original.
At this time, the first traveling body 24 for reading the reflection original is driven as a traveling body for reading the transparent original. The scanning method in the sub-scanning direction Y at the time of reading the reflection original can be performed in the same manner as in the first embodiment.

As described above, by sharing the sub-scanning traveling body of the reflection original reading system and the transmission original reading system, it is possible to reduce the configuration of the entire apparatus and reduce the cost. Further, by simultaneously moving the sub-scanning traveling system for reading reflection and transmission, and performing reading, the reflection original 1
And the transparent original 2 can be read at the same time and in a form synthesized as an image. Further, the imaging lenses 9 and 10
Since a zoom lens is used, enlargement and reduction by an arbitrary optical system are possible. However, the imaging lenses 9 and 10 need not necessarily be zoom lenses.

Next, a third embodiment of the present invention will be described with reference to FIG. The description of the same parts as in the first embodiment (see FIG. 1) is omitted, and the same reference numerals are used for the same parts.

In this embodiment, as in the second embodiment described above, the sub-scanning traveling system for reading the reflected and transmitted originals is shared. That is, the contact glass 7 for reading the transparent original is moved to the sub-scanning second traveling body 3 for reading the reflective original.
By fixing to 0, a sub-scanning second traveling body 31 for reading a reflection original is newly formed. Thus, as in the second embodiment, the traveling body for reading the transparent original can be omitted. When reading a transparent original, the second
The sub-scanning traveling system for reading the reflection original is driven so that the moving speed of the traveling body 31 becomes the speed at the time of reading the transmission original.
At this time, the sub-scanning second traveling body 30 for reading the reflected original is
Functions as a traveling body for reading a transparent original.

As described above, by sharing the sub-scanning traveling system between the reflection original reading system and the transmission original reading system,
As in the above-described second embodiment, it is possible to reduce the configuration of the entire apparatus and reduce the cost. Further, by simultaneously moving the sub-scanning traveling system for reading the reflection and transmission, and performing the reading, it is possible to read the reflection original 1 and the transmission original 2 at the same time and in a form synthesized as an image.

Furthermore, since zoom lenses are used for the imaging lenses 9 and 10, enlargement and reduction by an arbitrary optical system are possible. However, the imaging lenses 9 and 10 need not necessarily be zoom lenses.

[0039]

According to the first aspect of the present invention, there is provided a reflective original reading optical system having a light source for reading the reflective original and a mode for reading a transparent original such as a film, and a reflective original reading optical system having an original platen. It is possible to read the reflective original or the transparent original by forming a light source for reading the transparent original, and a transparent original reading optical system having an original table, and forming an image on the same photoelectric conversion element by different imaging lenses. A half mirror is installed at a position where an optical path of the reflection original reading optical system and an optical path of the transmission original reading optical system intersect, and the reflection original and the reflection original on the optical path synthesized by the half mirror are provided. the photoelectric conversion element disposed at a position transparent original is imaged simultaneously, illuminates the original document and Sukunakutomoi not a Re or the other document reflecting original or transparent original Between the source, since the disposed at least in some of the original barrier for document shields the irradiated light from the light source <br/> optical plate, when synthesizing a transmissive original and a reflection original, both of the original The need for the troublesome operation of reading and synthesizing the data into separate memories is eliminated, thereby partially separating the image-forming position on the photoelectric conversion element when reading both the reflection and transmission originals at the same time. Efficiency and memory saving can be achieved.

According to a second aspect of the present invention, in the first aspect of the present invention, the document light shielding plate is formed so as to have a boundary of light shielding of the document illumination light in the sub-scanning direction of document reading.
When combining a transmissive original and a reflective original, the troublesome operation of reading and synthesizing both originals in separate memories is not required. The image forming position of the original document on the photoelectric element can be separated, and the reading operation can be made more efficient and memory can be saved.

According to a third aspect of the present invention, in the first or second aspect of the present invention, at least one of the image forming lenses for reading a reflection original or a transmission original is formed on a zoom lens. This makes it possible to read a transparent original by zooming at different magnifications, thereby expanding its application range.

According to a fourth aspect of the present invention, there is provided the half mirror according to the first, second or third aspect, wherein the half mirror is disposed at a position where the optical path of the reflection original reading optical system and the optical path of the transmission original reading optical system intersect. Since the half mirror light-shielding plate is provided in the periphery, it is possible to prevent light that has passed through or reflected from the half mirror and is not directed to the photoelectric conversion element from illuminating the reflection original again, thereby deteriorating the reading accuracy. Can be prevented.

[Brief description of the drawings]

FIG. 1 is a vertical sectional side view showing a configuration of an image reading apparatus according to a first embodiment of the present invention.

FIG. 2 is a plan view showing a state of a document light shielding plate.

FIG. 3 is a plan view illustrating a state in which a boundary is formed on a document light-shielding plate.

FIG. 4 is a vertical sectional side view showing a configuration of an image reading apparatus according to a second embodiment of the present invention.

FIG. 5 is a vertical sectional side view showing a configuration of an image reading apparatus according to a third embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Reflective original 2 Transparent original 3 Light source 4 Original table 5 Reflective original reading optical system 6 Light source 7 Original table 8 Transparent original reading optical system 9, 10 Imaging lens 11 Photoelectric conversion element 12 Original light shielding plate 16 Half mirror 18 Original light shielding Plate 26 Boundary 28 Shield plate for half mirror Y Y Operation direction

Continued on the front page (51) Int.Cl. ⁷ Identification code FI H04N 1/10 G02B 27/00 G 1/107 H04N 1/10 1/19

Claims (4)

(57) [Claims] A light source for reading the reflection document; a reflection document reading optical system having a document table; a light source for reading the transmission document; and a document. An image reading apparatus that is capable of reading the reflective original or the transparent original by forming an image on the same photoelectric conversion element by using different image forming lenses from each other. A half mirror is installed at a position where the optical path of the original reading optical system and the optical path of the transparent original reading optical system intersect, and the reflective original and the transparent original on the optical path combined by the half mirror are imaged simultaneously. the photoelectric conversion elements arranged at a position, between the Re not a Sukunakutomoi the reflective original or the transparent original or the one document with the light source for illuminating the original An image reading apparatus, wherein a document light blocking plate for blocking light emitted from the light source is provided on at least a part of the document . 2. A document for shielding plate, the image reading apparatus according to claim 1, characterized by forming to be a boundary between the light shielding of the document illumination light in the sub-scanning direction of the original reading. 3. The image reading apparatus according to claim 1, wherein at least one of the imaging lens for reading the reflection original or the transmission original is formed in a zoom lens. 4. A claim, characterized in that disposed a light-shielding plate half mirror around a half mirror and the optical path is located where the optical path between the transparent original reading optical system of a reflection original reading optical system The image reading device according to 1, 2, or 3.