JPH0226469A - Reader - Google Patents

Abstract

PURPOSE:To attain low cast and high resolution reading by using the reading part of low density on reading an original normaly and using the reading part of high density on reading the original on purpose to enlarge. CONSTITUTION:On reading a non-transmissive original at low density, an output signal selecting circuit 23 is set to input the output signal a CCD 82 to a picture processing circuit 24, and the reading of a picture is executed by a low density reading part 8. On the other hand, on reading a reflected original at high density, a high density reading unit 90 is moved to the requested reading position of the non-transmissive original on original table glass 2 in a main scanning direction in advance. Then, the direction is set so that the aperture of a luminous source 70 may project to a position B, and after the output signal selecting circuit 23 sets the output signal of a CCD 92 to output, main scanning is executed with image-forming the image of the position B on a solid image pickup element 92 by a reading lens 91 by the irradiation of the light of the luminous source 70 and sub-scanning is executed by the driving of a motor. Thus, cost rising is suppressed, and the lowering of resolution is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a reading device for reading a document in an image forming apparatus such as a copying machine.

[Prior art]

In recent years, digital copying machines that can read originals with image readers and store and process the image information as electrical signals have become popular. As a result, devices have been developed that allow fairly large-sized copies to be obtained.

[Problem to be solved by the invention]

By the way, when obtaining a large-sized copy as mentioned above, it is enlarged by signal processing or read using an enlarging optical system, but when the enlargement ratio is large, the resolution of the image decreases. Put it away.

This is because the reading section only has a reading density that does not interfere with normal reading, and to prevent the resolution from decreasing when enlarged, use a reading section with a high reading density. There is a need. However, reading for the purpose of enlarging is not performed very often, and replacing the reading unit with one with a higher reading density just for that purpose may result in unnecessary cost increase, which is not preferable.

The present invention has been made in view of the above circumstances, and provides a reading system that suppresses unnecessary increases in costs by using existing equipment in combination, and enables reading that does not reduce the resolution for reading for the purpose of enlarging. The purpose is to provide equipment.

[Means for Solving the Problems] A reading device according to the present invention is a reading device that reads a document, and includes a plurality of reading sections having different reading densities, a selection means for selecting the reading sections, and a selection means for selecting the reading sections. The present invention is characterized by comprising a drive circuit that drives the reading section so that the document is read by the reading section.

[Effect]

The selected reading section is driven by the drive circuit, so that the document is read at the reading density of the reading section.

〔Example〕

The reading device according to the present invention (hereinafter referred to as the device of the present invention) includes:
Equipped with four reading modes depending on the type of document.
First, in mode 1, a normal opaque original is irradiated with light and an image is read using the reflected light. Mode 2 is a mode related to the main part of the present invention, and like mode 1, it reads an opaque original, but it reads at a higher density than mode 1, so when the read image is enlarged, This also prevents the image resolution from decreasing. Mode 3 is for reading a relatively large transparent original such as a transparent sheet for QHP, and its reading density is equivalent to mode 1. Mode 4 uses the method of mode 2 for reading opaque originals at high density to read small transparent originals, that is, photographic films at high density.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below based on drawings showing embodiments thereof. 1 and 2 are external perspective views of the apparatus of the present invention, in which the main body 1 of the reading apparatus is provided with a document table glass 2 on the upper surface, an operation panel 3 on the front side thereof, and a photograph of mode 4 on the left side. Opening 4 used when reading the film
(See FIG. 2), and the rectangular opening 4 has a longitudinal direction extending along the depth direction of the original platen glass 2.
That is, it is provided to match the depth direction of the reading device main body 1. In the opening 4, a seat plate 40 for mounting the film holder 5 and light box 6 shown in FIG. Holes 41 and 41 are formed in the vicinity of parts of both corners near the document table glass 2. Further, on the left side edge of the opening 4, a plurality of photo-interchangers 42 for detecting the position of the light box 6, which will be described later, are arranged side by side at equal intervals.

When the film holder 5 and light box 6 are not attached, that is, when mode 4 reading is not performed, the opening 4 is sealed with a lid (not shown) to prevent operations in other reading modes. It is configured so that it does not become

FIG. 3 is a perspective view showing the internal structure of the reader main body 1. At the inner bottom of this, a pair of rails 10a having a length slightly shorter than the width of the reader main body 1 are provided.

10b are disposed facing each other with their longitudinal directions aligned with the width direction of the reading device main body 1, and the rails IQa.

A rectangular parallelepiped-shaped reading rail 7 having a depth slightly shorter than the depth of the reading device main body 1 is placed on the reading rail 10b so that the longitudinal direction thereof is orthogonal to the extending direction of each rail. A pulley l is mounted on the rails 10a and 10b and driven by a motor 13, respectively.
la, llb and the wire 12a stretched between them,
12b, it moves on the rails 10a, 10b in the width direction of the reader main body 1, that is, in the horizontal direction.

FIG. 4 is a longitudinal cross-sectional view of the reading head 7 taken in a direction perpendicular to the depth direction and viewed from the front, and FIG. 5 is a perspective view showing the internal structure of the reading head 7. The reading head 7 has an opening 9 formed in the center of its upper surface over the entire length in the depth direction, and a glass plate 74 is sealed in the opening. low density reading section 8,
Furthermore, a high-density reading section 9 used in modes 2 and 4 is provided respectively, and is made of, for example, an aperture-type fluorescent lamp located near the glass plate 74 with its axial length direction being the depth direction of the reading head 7. A light source 70 is arranged. The light source 7
0 has a length substantially equal to the length in the depth direction of the original platen glass 2, and is mounted so as to face the lower surface of the original platen glass 2 through a glass plate 74, as shown in FIG. 6, which will be described later. It can be rotated in the circumferential direction by a drive mechanism.

The low-density reading section 8 is disposed on the right side of the light source 70, and the low-density reading section 8 includes an imaging element (lens) 81 and a solid-state imaging element, each having approximately the same length as the light source 70.
For example, it is composed of a CCD 82, and an imaging element 81.
The incident side of the light is placed facing the glass plate 74, and the CCD 82 is placed oppositely below the exit side. In other words, the low-density reading section 8 is configured so that its longitudinal direction coincides with the depth direction of the document table glass 2 to perform main scanning on the document.

The left side of the light #70 has a reading width in the main scanning direction of 115 to 1/10 of the reading width in the main scanning direction of the low-density reading section 8, and this is the reading width in the main scanning direction of the low-density reading section 8. A high-density reading section 9 is disposed parallel to the scanning direction, that is, in the main scanning direction of the document table glass 2.The high-density reading section 9 is composed of a reading lens 91 and a solid-state image sensor 92, The entrance side of the reading lens 91 is placed facing the glass plate 74, and the CCD 92 is placed facing below the exit side. As the reading lens 91, for example, a convergent rod lens is used, which is a solid ↑ for high-density reading in boat fishing.
This is to obtain a sufficient S/N ratio during high-density reading, since the most image element has lower sensitivity than those for low-density reading. The high-density reading unit 9 is a rectangular box-shaped high-density reading unit 9 whose one end is inserted through a shaft 73 that is disposed parallel to the axial direction of the light source 70 over the entire length of the reading head 7 in the depth direction.
The high-density reading unit 1-90 is equipped with a roller 93 on the side opposite to the insertion portion of the shaft 73, and the rotation axis of the roller 93 is perpendicular to the longitudinal direction of the shaft 73. Yes, there is a stepping motor 72 installed in the reading head 7.
The device is configured to move in the longitudinal direction of the shaft 73, that is, in the depth direction of the reading head 7, by the pulleys 71a and 71b driven by the pulleys 71a and 71b and the wire 75 stretched between them.

FIG. 6 is a longitudinal sectional view showing an example of a drive mechanism that rotates the light source 70 in the circumferential direction.
The rack teeth of the light source 70 are meshed with the teeth 76 formed on a part of the peripheral surface of the light source 70, and the aperture 0a of the light source 70 is moved in the direction of the position A when the rack 77 is protruded, and when it is retracted. In this case, the irradiation direction can be switched to either of the two directions A and B.

FIG. 7 is a block diagram showing the configuration of the drive circuit when an image is read by the low-density reading section 8 and the high-density reading section 9. The output of the drive pulse generation circuit 21 is sent to a CCD for low density reading via a drive pulse on-off circuit 22.
When the driving pulse on-off circuit 22 is turned on, the reference clock pulse generated by the driving pulse generating circuit 21 is applied to the CCD 82 and the CCD 92, respectively. .

Each output signal of the CCD 82 and CCD 92 is input to an output signal selection circuit 23, and the output signal selection circuit 23 outputs either one of the output signals photoelectrically converted by the CCD 82 or the CCD 92 to the image processing circuit 24. Please input it to . That is, CCD 82 and CCD 92
The drive pulse generation circuit 21 and the image processing circuit 24 are shared by using the same clock pulse, that is, by making the accumulation time of the optical signal of the CCD the same.

Now, in the above configuration, reading operations in modes 1.2 and 3 will be explained. First, when reading an opaque original in mode I at low density, the aperture 0a of the light source 70 is
The direction is set so that the light is projected to the position A, and the output signal selection circuit 23 is set so that the output signal of the CCD 82 is input to the image processing circuit 24. Then, the light from the light source 70 is irradiated onto the lower surface of the non-transparent original placed on the original platen glass 2, and this diffusely reflected light is imaged on the CCD 82 by the imaging element 81 of the low-density reading section 8. Main scanning is performed by scanning the main line, and one line of image information is obtained.

Further, by driving the motor 13, the scanning radar 7 is moved in the width direction of the main body 1 of the reading apparatus, thereby performing sub-scanning of the original image. Here, the image reading density by the low-density reading section 8 is 10 to 20 pixels/I.

Next, when reading a reflective original in mode 2 at high density, first drive the high-density reading unit in advance by driving the stepping motor 72 so that the original platen glass 2 in the main scanning direction
Move the upper opaque document to the desired reading position. Then, the direction of the aperture 70a of the light source 70 is set to project light to the position B, and the output signal selection circuit 23 is set to output the output signal of the CCD 92. By irradiating the light, an image at the position B is formed by the reading lens 91 onto the solid-state imaging element 92 to perform main scanning, and by driving the motor 13, sub-scanning is performed.

The reading density of the image by this high-density reading section 9 is 50~
200 pixels/ll11, and when compared with the low-density reading section 8, the resolution does not decrease even if the read image is enlarged.

When reading a large transparent original at low density in mode 3, a light hood shown in FIG. 8 is used. Figure 8 shows
FIG. 3 is a longitudinal cross-sectional view showing a state in which the light hood is attached to the reading device main body 1. FIG. The light hood 10 placed on the document table glass 2 of the reading device main body 1 has a square pyramid shape, and is equipped with a light source 11 at the top of the light hood 10, and a heat-insulating filter arranged below the light hood 10 to direct the light from the light source 11. 12 to diffuse irradiation to the bottom side. A Fresnel lens 13 and a transmission diffusion plate 14 are arranged in a laminated manner at the bottom, and the lower surface side of the transmission diffusion plate 14 is placed opposite to a transmission original (not shown) placed on the original platen glass 2. be. The transmission diffuser plate 14 is provided to alleviate illumination unevenness such as an annular shadow of the Fresnel lens 13. Reading of the transparent original is performed by the low-density reading section 8 in the same manner as in mode 1.

As described above, in all modes 1 to 3, an original is placed on the original platen glass 2 and the original image is scanned.

Next, the structure of the film holder 5 and light box 6 for reading photographic film in mode 4 will be explained. 9 and 10 are external perspective views showing the structure of the film holder 5. The long plate-shaped film holder 5, which is fitted into the opening 4 of the reader main body 1, has an image of the film in the center. It is constructed by integrally bonding a holding plate 5a and a substrate 5b, each having rectangular openings 50a and 50b whose short sides are approximately equal in length to the width, and by changing the way these are bonded, a slide film can be formed. or ordinary negative film can be interposed and held between both members.

FIG. 9 shows a case where a slide mount on which a slide film is mounted is held, and the substrate 5b has a recess 5H+ on the upper surface of which the slide mount is inserted and placed.
, 51b are formed at two locations on each side edge portion in the length direction of the opening 50b, that is, two recesses, for a total of four locations. The depth of the recess 51b is determined so that the height of the top surface is lower than the top surface of the substrate 5b.
There are pins 58.5 near both corners on the front side of the top surface of this.
8, and also pins 59 near both corners on the back side of the bottom surface.
．． 59 (see Figure 1O) are provided in a protruding manner. The holding plate 5a has four convex portions 51a on its lower surface that fit into the concave portions 51b of the substrate 5b (see FIG. 10).
It is formed at the side edge in the length direction of the opening 50a, and the protrusion height of this protrusion 51a from the lower surface of the holding plate 5a is the same as when the slide mount is inserted and placed in the recess 51b of the board 5b. The length is set to be approximately equal to the length from the top surface of the slide mount to the top surface of the substrate 5b. At the positions between the convex portion 51a and both edges in the longitudinal direction of the presser plate 5a, there are provided lengths that are slightly shorter than the length of the presser plate 5a (and whose longitudinal direction coincides with the lengthwise direction of the presser plate 5a). Hole-shaped guide holes 52, 5
2 is formed by penetrating it in the thickness direction. A groove 550 whose longitudinal direction coincides with the longitudinal direction of the holding plate 5a is formed on the front side surface in the longitudinal direction of the holding plate 5a, and the liquid groove 550 has recessed holes 55, 55 having a hole diameter larger than the groove width. ．． ... are drilled at equal intervals. Near both corners on the front side are holes 53.53 into which the pins 58.58 of the board 5b are inserted.
is formed by penetrating it in the thickness direction.

When holding a slide mount with the film holder 5 configured as described above, first, the slide mount (not shown) is inserted and placed in the four parts 51b, 51b of the substrate 5b. The parts 51a, 51a are fitted into the recesses 51b, 51b, and the pins 58, 58 of the board 5b are fitted into the holes 53,53 of the holding plate 5a, thereby joining the holding plates 5a, l!: to the board 5b. As a result, the side edges of the slide mount are sandwiched, and the openings 50a and 50b are located in a direction perpendicular to the screen of the image portion of the slide film, so that both sides of the image are exposed to the outside.

Figure 10 shows a case in which a negative film, that is, a film piece cut into a predetermined number (usually 5 frames) of a single film to be stored in a storage case, is held. 5a and the substrate 5b, the surfaces opposite to the surfaces shown in FIG. 9 are used. The upper surface of the substrate 5b (9th
Opening 5 in the center part in the width direction on the lower surface in the figure
A recessed portion 57b having a bottom portion wider than the width of the substrate 5b and approximately equal to the width of the film is formed over the entire length of the substrate 5b in the longitudinal direction.

Also, as mentioned above, pins 59 and 59 are protruded near both corners on the front side of the top surface. Pressing plate 5a
A convex portion 56a, which is fitted into the recess 57b, is formed on the lower surface (upper surface in FIG. 9) of the holding plate 5a, extending along the entire length of the holding plate 5a. A groove 560 having exactly the same structure is provided on the front side surface of the presser foot Fi5a, that is, on the side surface opposite to the side surface where the groove 550 and the recessed holes 55, 55, etc. are formed.
and recessed holes 56, 56. ...is formed.

Holes 54, 54 into which the pins 59, 59 of the board 5h are inserted are located near a portion of both corners on the front side, that is, near a portion of the corner where the holes 53, 53 are formed and a portion of the corner on the opposite side.
is formed by penetrating it in the thickness direction.

When holding a film piece with the film holder 5 configured as described above, the film piece is held in the recess 5 of the substrate 5b.
7b and place it there. And a convex portion 56a of the presser plate 5a
is fitted into the recess 57b, and the pin 59 of the board 5b is fitted into the recess 57b.
．． 59 are fitted into the holes 54 and 54 of the presser plate 5a to connect the presser plate 5a and the substrate 5b. As a result, the film piece is sandwiched at its winding hole portion and both ends in the length direction, and the openings 50a and 50b are located in the direction perpendicular to the screen of the image portion of the film, so that both sides of each image are exposed to the outside. Let them come to you.

FIG. 11 is an external perspective view showing the state in which the light box 6 is attached to the film holder 5, and FIG. 12 is a longitudinal section of the main body 1 of the reading device including a longitudinal section taken along the line x-xn showing its internal structure.
FIG. 2 is a vertical cross-sectional view of a main part showing a state in which the film holder 5 is attached to the camera, and shows a state in which the film holder 5 holds a slide mount.

The light box 6 has a rectangular parallelepiped shape with a bottom that is approximately the same size as the slide mount 100 held by the film holder 5, and has pedestals 68a and 68b extending from both ends of the bottom in the depth direction. Each pedestal 68a,
Guide holes 52.5 formed in the holding plate 5a of the film holder 5 are connected to protrusions 68c and 68d provided on the lower surface of the film holder 5.
2 and is movable in the longitudinal direction of the film holder 5. Further, when holding a slide film or a piece of film, a recess 69 that engages with the projection 57a or both of the projection 51a located on the upper surface of the presser plate 5a is provided at the bottom for the entire length in the width direction, that is, in the moving direction. It was formed over a period of time.

A positioning plate 66 for selecting a film image to be illuminated and a light shielding plate 67 used for detecting the position of the light box 6 on the film holder 5 are attached to the pedestal 68a. The positioning plate 66 is bent like a leaf spring from the upper surface of the pedestal 68a to the lower side of the light box 6, and a hemispherical protrusion provided at the center of the positioning plate 66 is engaged with a groove 550 formed on the side surface of the holding plate 5a. Let's match and lie [
- It is designed to slide as the box 6 moves, and is placed in a recessed hole 55 that is formed based on the longitudinal arrangement position of the film holder 5 of the slide mount 100 and the arrangement interval of each frame of the negative film. By fitting, the film image is positioned. The light shielding plate 67 protrudes forward from the upper surface of the pedestal 68a, and when the light box 6 and the film holder 5 are installed in the opening 4 of the reading device main body 1, the light shielding plate 67 is inserted into each of the photointerrupters 42. The light box 6 is interposed in the vertically provided optical path and blocks light.
The position on the film holder 5 is detected.

As shown in FIG. 11, the inside of the light box 6 includes a light source 61 for film illumination on the top thereof, a heat shielding filter 62 on the bottom thereof, and a cooling fan 65 on the negative side. A collimator lens 63 and a transmission diffusion plate 64 are arranged in a laminated manner at the bottom, and the lower surface of the transmission diffusion plate 64 is configured to face the film of the film holder 5.

The operation of reading an image on a photographic film using the film holder 5 and light box 6 constructed as described above will now be described. First, the operator holds either the slide mount or the film piece with the film holder 5 as described above, attaches the light box 6 to this, and then
Or, if you want to install it later, please use the reader body 1 as is.
It is installed in the opening 4 of the This attachment is carried out using bins 58 and 58 located on the lower surface side of the substrate 5b, depending on the film held.
or 59.59 by fitting into the hole 41.41 provided in the seat plate 40 in the opening 4.

Then, by moving the light box 6 attached to the film holder 5 in the longitudinal direction of the film holder, the light box 6 is positioned over a desired image. Here, it is also possible to confirm the image more clearly by turning on the light *7o of the reading head 7.

On the reading device side, the position of the light box 6, that is, the position of the image to be read, is detected by the photointerabutter 42, so that the high-density reading unit 9 of the high-density reading unit 90 reads the image as shown in FIG. It moves in the main scanning direction to set it to the reading start position. When this is finished, if the light source 70 of the reading head 7 is lit,
After turning off this light, the light #61 of the light box 6 is turned on to illuminate the image, and the high-density reading section 9 starts reading the transmitted light image. Here, the output signal selection circuit 23 is set in advance to input the output signal of the CCD 92 to the image processing circuit 24 as in mode 2.

In this embodiment, the film holder is configured to be mounted with an opening provided on the left side of the top surface of the reader with the longitudinal direction of the film holder aligned with the main scanning direction of the reader. It is also possible to configure the sensor to be mounted, for example, on the front portion of the upper surface of the reading device so as to match the sub-scanning direction. In other words, the direction in which the film images are arranged side by side is the main scanning direction of the document table.
Alternatively, by matching the sub-scanning direction, if a high-density reading section is installed, the drive system and operation system for moving it can be shared with the existing low-density reading section, and the increase in parts can be minimized. , it is possible to suppress cost increases. In this embodiment, an aperture-type fluorescent lamp is used as the light source when reading a reflective original, but instead of this, a structure may be used in which the direction of the reflective shade of a halogen lamp is changed, and a reflective original can be read at a high density. If the illuminance of the light source is insufficient for reading, an auxiliary light source may be provided. Further, in this embodiment, a convergent rod lens is used in the high-density reading section, but if the amount of light is sufficient, a through lens may be used to configure the zoom optical system.

In addition, a photo-interchanger is used to detect the position of the light box on the film holder, but it is not limited to this (a micro switch, etc. may also be used. In addition, in this embodiment, Although the number of slide mounts that can be held in parallel on the film holder is two, it goes without saying that a configuration that can hold two or more sheets may also be used.

〔effect〕

As described above, in the reading device according to the present invention, when reading a document normally, a low-density reading section is used, and when reading a document for the purpose of enlarging, a high-density reading section is used. As a result, even if an image read by a high-density reading unit is enlarged, the resolution does not decrease, and a high-resolution read image can be obtained. In addition, one of the reading sections can be an existing one in the conventional device, so it is only necessary to provide the conventional device with a high-density reading section with high reading density, and its drive circuit can be either low-density or high-density. By sharing the existing one for the reader instead of providing one for each,
Unnecessary cost increases can be suppressed. Furthermore, the high-density reading unit can read small transparent originals such as photographic film with high density by using a small light box, etc., and as a result, it is possible to read film images with high density using a projector etc. The present invention has excellent effects such as eliminating the need to secure a large space for the optical path for enlarging and projecting the film when reading it by enlarging it, and allowing easy high-resolution reading even in a limited space. play.

[Brief explanation of the drawing]

1 and 2 are external perspective views of a reading device according to the present invention, FIG. 3 is a perspective view showing its internal structure, FIG. 4 is a vertical sectional view of the reading head, and FIG. 5 is a perspective view of its internal structure. A perspective view showing,
Fig. 6 is a longitudinal sectional view showing the drive mechanism for switching the irradiation direction of the light source, Fig. 7 is a block diagram showing the configuration of the drive circuit of the reading section, and Fig. 8 is a longitudinal sectional view showing the state in which the light hood is attached. , FIG. 9 and FIG. 10 are external perspective views of the film holder, FIG. 11 is an external perspective view showing how the light box is attached to the film holder, and FIG. 12 is an external perspective view showing how the light box and film holder are attached to the reading device main body. FIG. 3 is a vertical cross-sectional view of the main part showing the installed state. 1...Reading device main body 2...Original table glass 4...
・Opening portion 5...Film holder 6...Light box 7...Reading head 8...Low density reading section 9
... High-density reading section 21 ... Drive pulse generation circuit
23... Output signal selection circuit

Claims (1)

[Scope of Claims] 1. A reading device for reading a document, comprising: a plurality of reading sections having different reading densities, a selection means for selecting the reading sections, and a reading section selected by the selection means reading the document. A reading device comprising: a drive circuit for driving the reading section.