JP3109096B2 - Image scanner - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an image scanner used as an image input device provided in a personal computer, a word processor, or the like.

[Conventional technology]

Image scanners provided as image input devices installed in personal computers and word processors usually scan light from a light source onto a non-transparent document placed on a platen glass, and read reflected light with a line sensor or the like. ing. As a method of reading a transparent original such as a photographic film with such a device, a method of enlarging and projecting a film image on a platen glass by a projector and reading the image with a sensor, as in a conventional copying machine, is known. there were. Alternatively, by providing a reflection plate on the document holding plate, the image is read by a line sensor similarly to a normal opaque document, and the read image is enlarged by signal processing.

[Problems to be solved by the invention]

However, of the above-mentioned conventional methods, the former requires the use of a projector, which requires a large space for the optical path from the projector and the transparent document to the platen, and has a problem that the apparatus becomes large. .

The latter is small and simple as a device, but has a problem that the resolution is reduced when the image read by the sensor is enlarged by signal processing because the film image is usually small.

The present invention has been made in view of the above points, and can easily switch between an opaque document and a transparent document to read at a high resolution. An object of the present invention is to provide an image scanner having a small size and a simple structure.

[Means for solving the problem]

An image scanner according to the present invention includes a document table on which an opaque document is placed, a light source that moves along the lower surface of the document table to illuminate the document, and a first imaging lens that guides reflected light from the document to a reading unit. An image scanner having a first optical system having: a support unit provided on a part of a document table for mounting a transparent original; a light source for illuminating the transparent original; and a reading unit for transmitting transmitted light from the transparent original A second optical system disposed on the same side of the platen as the first optical system, the second optical system having a second imaging lens different from the first imaging lens leading to the first optical system; Switching means for switching between the optical path of the reflected light and the optical path of the transmission system of the second optical system, and guiding one of the optical paths to a reading unit common to the reflected light and the transmitted light. Image scanner. The image scanner according to claim 1, wherein the second optical system enlarges the transparent original and forms an image on a reading unit.

[Action]

In the image scanner having the above configuration, the image of the transparent original is guided to the reading unit via the second optical system by light transmitted from the light source through the transparent original. Therefore, by the high-density optical lens provided in the second optical system, a reduction in resolution can be prevented, and a small transparent original can be enlarged and projected on the reading unit.

Further, since the optical paths of the respective optical systems of the opaque document and the transparent document are switched by the switching unit and guided to the reading unit, a projector or the like is not required, and the apparatus can be reduced in size and can have a simple structure. .

〔Example〕

Hereinafter, embodiments of the image scanner of the present invention will be described with reference to the drawings.

FIG. 7 is an external perspective view of each embodiment of the present invention.
FIG. 1 is a schematic configuration diagram showing a first embodiment of the present invention. In FIG. 7, a document table 2 on the upper surface of the image sensor main body 1 is shown.
Has a rectangular opening, and a document table glass 3 on which an opaque document is placed is mounted on the opening. Further, a supporting portion 5 on which the photographic film 4 is placed is provided on the side of the platen glass 3 on the platen 2.

In FIG. 1, along the lower surface of the platen glass 3, 1
A pair of carriages 11 and 12 are provided so as to be able to travel. A first lamp, which is a first light source, is provided in the first carriage 11.
13 and a first mirror 14 are attached. Also the second
A second mirror 15 and a third mirror 16
And are attached. Light emitted from the first lamp 13 is radiated linearly toward the platen glass 3 through a slit (not shown). Then, the light irradiates the opaque document 17 placed on the platen glass 3, and the reflected light thereof is reflected by mirrors 14, 15,
The light is reflected by 16 and travels in a direction parallel to the platen glass 3.

A lens 19, a half mirror 20, and a line sensor 21 serving as a reading unit are provided on an optical path 18 of the light reflected by the third mirror 16.
Is provided in a fixed position. Lens 19 is manuscript 17
Is formed on the light receiving surface of the line sensor 21. The traveling speed of the first carriage 11 is twice as fast as the traveling speed of the second carriage 12, and the first ramp 13
The optical path length from the line sensor 21 to the line sensor 21 is always constant.

On the other hand, the half mirror 20 is at an angle of 45 degrees with respect to the optical path 18, and the original is a transparent original on the original table 2 on the optical path 22 which is symmetrical to the optical path 18 with respect to the normal of the half mirror 20. A support section 5 on which the photographic film 4 is placed is provided. The supporting portion 5 has a box shape as shown in FIG. 7, and a portion of the document table 2 facing the bottom surface is open, and a glass plate 23 is attached to the opening. In the support portion 5, a second lamp 24, which is a second light source having a center on the optical path 22, and a reflector 25 are provided. Further, the supporting portion 5 is provided with a roller 26 for feeding the photographic film 4 on the glass plate 23. A high-density reading lens 27 is provided on the optical path 22.

 Next, the operation of the present embodiment will be described.

When reading a normal opaque original 17, the original 17 is placed on the original platen glass 3, and the first lamp 13 is turned on.
The second lamp 24 is turned off. Then, the carriages 11 and 12 are moved in the direction shown by the arrow A, and the original 17 is scanned by the light emitted from the first lamp 13. Then, the reflected light from the original 17 is reflected by the mirrors 14, 15, and 16, the reflected light is advanced along the optical path 18, and the image is formed on the light receiving surface of the line sensor 21 by the lens 19 for reading. At this time, since the mirror 20 is a half mirror, the reflected light travels straight on the optical path 18.

When reading a transparent original such as the photographic film 4, the photographic film 4 is inserted into the support portion 5 by the roller 26 and the photographic film 4 is set. Then, the first lamp 13 is turned off and the second lamp 24 is turned on to illuminate the photographic film 4 linearly. The light transmitted through the photographic film 4 is enlarged while maintaining high resolution by the high-density reading lens 27, reflected by the half mirror 20, focused on the light receiving surface of the line sensor 21, and read. The reflection plate 25 is for collecting the light of the second lamp 24 on the photographic film 4.

The sub-scanning of the photographic film 4 is performed by the rollers 26.
This is performed by moving the photographic film 4.

According to this embodiment, the high-density reading lens 27 prevents the photographic film 4 that is a transparent original from lowering in resolution,
Since the image can be enlarged and formed on the light receiving surface of the line sensor 21, the information on the small photographic film 4 can be accurately read. Further, since a projector or the like is not required, the structure of the apparatus can be simplified and the apparatus can be reduced in size. Furthermore, since the half mirror 20 is provided on the optical path 18,
By simply switching the lighting of the light sources 13 and 24, the reading of the opaque original 17 and the photographic film 4 can be easily switched.

 2 to 6 show another embodiment of the present invention.

In these figures, parts corresponding to the parts of the first embodiment shown in FIG. 1 are denoted by the same reference numerals, and their remarks are omitted as appropriate.

FIG. 2 shows a second embodiment of the present invention. In this embodiment, the mirror 20 provided between the lens 19 and the line sensor 21 on the optical path 18 is rotatable. In this case, the mirror 20 may be a normal reflecting mirror having a reflecting surface formed only on the line sensor 21 side, and is parallel to the position a at an angle of 45 degrees with respect to the optical axis 18 about the support shaft 31. It is rotatable between the position b. When the opaque document 17 is read, the mirror 20 is set at the position b, and when the photographic film 4 is read, the mirror 20 is set at the position a.

FIG. 3 shows a third embodiment of the present invention. In this embodiment, the mirror 20 shown in FIG. 2 can be moved up and down. When reading the opaque document 17, the mirror 20 is moved up and down to remove it from the optical axis 18 and set to a position c, for example. When reading the photographic film 4, the mirror 20 is moved 45 degrees to the optical axis 18.
The position a is an angle of degrees.

FIG. 4 shows a fourth embodiment of the present invention. In the present embodiment, a fifth mirror 41 is provided on the optical path 22 shown in FIG. 1 at an angle of 45 degrees with respect to the optical path 22 separately from the half mirror 20 as the fourth mirror. The lens 19 and the line sensor 21 are provided on the reflection optical path. The fourth mirror 20 may be a fixedly provided half mirror,
As shown in FIG. 2 or FIG. 3, a normal mirror that can rotate or move may be used. When reading the opaque document 17, the light is reflected by the mirrors 20 and 41 and is imaged on the light receiving surface of the line sensor 21 by the lens 19. When reading the photographic film 4, the light passes through the lens 27, passes or passes through the mirror 20, is reflected by the mirror 41, and is similarly imaged on the light receiving surface of the line sensor 21.

5 and 6 show a fifth embodiment of the present invention. In this embodiment, the second lamp 24 in the support portion 5 shown in FIG. 1 is omitted, and the photographic film 4 is illuminated by the first lamp 13 in the first carriage 11. A reflection plate 51 for reflecting light emitted from the first lamp 13 toward the photographic film 4 is provided in the support portion 5. Further, a shielding plate 52 for preventing unnecessary light from entering the reflecting plate 51 is provided on the lower surface of the document table glass 23 in the supporting portion 5 on the first carriage 11 side. Further, the lamp 13 irradiates the opaque document on the platen glass 3 and the lamp 13 and the document when the first carriage 11 comes closest to the supporting portion 5 so that the reflected light does not enter the mirror 20. Base glass 3
A shielding plate 53 is provided between the first and second ends.

In the above configuration, when reading the opaque document 17, the reflected light from the document 17 is imaged on the light receiving surface of the line sensor 21, as in the first embodiment. When reading the photographic film 4, the first carriage 11 is
The light emitted from the lamp 13 is reflected by the reflector 51, and the light transmitted through the photographic film 4 is imaged on the light receiving surface of the line sensor 21 as in the first embodiment.

According to the second to fifth embodiments, the same effects as those of the first embodiment can be obtained.

In each of the above embodiments, the case where the transparent original is the photographic film 4 has been described. However, the transparent original is not limited to the photographic film 4.

〔The invention's effect〕

As described above, according to the image scanner of the present invention, an optical system that reads an opaque document and a transparent document is separately provided, a means for switching the optical path of each optical system is provided, and an optical system that reads a transparent document is provided. Since the high-density optical lens is provided, the transmission original can be enlarged and read accurately without lowering the resolution. In addition, the structure of the apparatus can be simplified and the size can be reduced, and it is possible to easily switch between reading a transparent document and a non-transparent document.

[Brief description of the drawings]

1 to 5 are side views showing a schematic configuration of the first to fifth embodiments of the present invention, FIG. 6 is a perspective view of a main part of FIG. 5, and FIG. 7 is a configuration of each embodiment. FIG. 1 image scanner body, 2 platen, 4 photographic film (transparent original), 5 support, 13 lamp, 1st lamp, 14, 15, 16, 20, 41 mirror 17: opaque original, 18, 22, 42 ... optical path, 19, 27 ... lens, 21 ... line sensor (reading unit), 24 ... second lamp.

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yasuhiro Okada 10 Ohana Dodocho, Ukyo-ku, Kyoto-shi, Kyoto (56) References JP-A-63-102457 (JP, A) JP-A-3-3 58566 (JP, A) JP-A-1-284067 (JP, A) JP-A-2-112375 (JP, A) JP-A-1-311763 (JP, A) Japanese Utility Model Application Sho 62-58957 (JP, U) (58) Field surveyed (Int.Cl. ⁷ , DB name) H04N 1/04-1/207

Claims (2)

(57) [Claims] A first platen on which an opaque document is placed; a light source which moves along a lower surface of the platen to illuminate the document; and a first light guide for guiding reflected light from the opaque document to a reading unit. An image scanner comprising: a first optical system having an imaging lens; a support provided on a part of the document table for mounting a transparent document; a light source for illuminating the transparent document; A second imaging lens different from the first imaging lens that guides the transmitted light to the reading unit, the second imaging lens being disposed on the same side as the first optical system with respect to the document table. And an optical path of reflected light of the first optical system;
An image scanner provided with switching means for switching an optical path of a transmission system of the second optical system and guiding one of the optical paths to the reading section common to the reflected light and the transmitted light. . 2. The apparatus according to claim 1, wherein the second optical system enlarges the transparent original and forms an image on the reading unit.
The image scanner according to 1.