JPH0351351B2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a scanning copying machine, a facsimile machine,
The present invention relates to an image reading device used in an OCR device, an electronic filing device, etc.

[Technical background of the invention and its problems] Conventionally, image reading devices used in scanning copying machines, facsimile machines, etc. often use a combination of an IC sensor such as a CCD linear image sensor and a spherical lens system. are doing. Incidentally, in recent years, there has been a strong desire from consumers for devices to be smaller, mesotenance-free, and easier to adjust optical systems and the like. However, since a spherical lens system is used, no countermeasure has been found yet.

In order to meet these consumer demands, contact image sensors are attracting attention and are being actively developed. An image reading device using this contact type image sensor uses an optical system for 1-magnification imaging, such as a converging rod lens array, on a photoelectric conversion element array having an array length that is approximately the same as the original as the object to be image read. This is a device that forms an image of a document and reads image information on the surface of the document. Since this image reading device can shorten the optical path of the optical system, it not only makes the device more compact, but also integrates the photoelectric conversion section, optical system, and illumination light source. It can be handled as an image sensor module. Therefore, this image reading device has the advantage that the main adjustments of the optical system can be made on a module-by-module basis, and that it can be easily incorporated into the main body of the device, such as a scanning copying machine. In addition, when reading a document by fixing it and moving the image sensor, it is possible to move the entire module, which reduces the number of moving parts in the optical system, which is advantageous in terms of maintenance.

Next, the above-described image reading device will be explained with reference to FIGS. 2 and 3.

FIG. 2 is a schematic sectional view showing an example of an image reading device developed by the present inventor prior to the present invention.
In FIG. 2, a light source for illumination, such as an LED array light source 12, a focusing rod lens array 13, and
An image sensor 14 made of an alumina substrate or the like and equipped with a photoelectric conversion section made of a CCD is integrated by being fixed to a support member 15 made of aluminum.

Next, the support member 15 will be explained in detail with reference to FIG. FIG. 3 is a schematic perspective view of the support member 15 shown in FIG. 2.

In FIG. 3, this support member 15 is manufactured as an integral piece, for example, by using a method in which an extrusion molded material is machined only at the necessary portions. By the way, in this case, much depends on machining. For example, guide holes for attaching focusing rod lens arrays are made by milling, but not only is the process itself expensive, but the guide holes become barrel-shaped due to the recess of the blade. When a convergent rod lens array is installed in a device, there is a danger that the optical axis of the convergent rod lens array may bend or sag, making focusing difficult, and furthermore making it difficult to correct the curvature or sagging.

[Purpose of the invention]

In view of the above-mentioned problems, it is an object of the present invention to provide an image reading device which is small in size and whose optical system can be easily adjusted.

[Summary of the invention]

In order to achieve the above object, the present invention divides a support member that supports an illumination light source, a focusing rod lens array, and an image sensor consisting of a photoelectric conversion element into at least two parts, and combines the support members. It is characterized by being connected by a member.

To be more specific, a focusing rod lens array is sandwiched between at least two or more supporting members, and the focusing rod lens array is held by a holding jig such as a screw provided on the supporting members. Attach. On this support member, an illumination light source such as an LED array is bonded using epoxy resin or the like, facing the focusing rod lens array. This connection of the supporting members is performed by a connecting member having a thickness equal to or greater than the thickness of the focusing rod lens. This connecting member includes
There is an adjustment mechanism for focusing the focusing rod lens array. An image sensor made of a photoelectric conversion element is provided at a position on the support member that faces the LED array through the focusing rod lens array.

[Embodiments of the invention]

Next, an embodiment of the image reading apparatus of the present invention will be described with reference to FIG. Note that FIG. 1 is a partially cutaway simplified perspective view of the image reading device.

In FIG. 1, supporting members 1a and 1b made of aluminum sandwich connecting members 2a and 2b made of iron at both ends thereof.
2b (the connecting members are made by welding each part, etc.) using screws 3, and are connected. Pins 4 provided on these coupling members 2a, 2b
is positioning the support members 1a and 1b. A light source for illumination, such as the LED array 5, is adhesively fixed to the supporting members 1a and 1b via an epoxy resin or the like (not shown). Further, the image sensor 6 in which a photoelectric conversion element such as a CCD is attached to a ceramic substrate is constructed by screwing a thin iron plate 7 to the supporting members 1a and 1b so as to face the LED array 5. , 1b. The thickness of the coupling members 2a and 2b is greater than or slightly thicker than that of the focusing rod lens array 8, and the light is focused in the gap between the supporting members 1a and 1b caused by the thickness. A rod lens array 8 is installed. After this focusing rod lens array 8 is focused by means of focusing, for example, a screw 9 and a spring 10, the focusing rod lens array 8 is attached to the coupling members 2a and 2b. It is pressed and fixed against the support member 1a at several locations in the longitudinal direction by set screws 11.

With the above structure, the guide hole of the focusing rod lens array 8 is formed by the gap between the supporting members 1a and 1b created by the thickness of the connecting members 2a and 2b without machining. . Therefore, by controlling the thickness of the coupling members 2a, 2b and the surfaces of the supporting members 1a, 1b, the shape of the guide hole can be formed with high precision. Furthermore, by matching the thickness of the coupling members 2a and 2b to the thickness of the focusing rod lens array 8, discontinuities between the guide hole and the focusing rod lens array 8 can be prevented.
can be reduced. Therefore, the focusing rod lens array 8 is less likely to bend or sag, making focusing easier. In addition, when fixing with the set screw 11, bending or sagging can be corrected. Furthermore, by making the supporting members 1a and 1b from extruded material, most of the machined parts are hole-machined, which has the effect of making it possible to manufacture them at low cost.

In the embodiment, the connecting members 2a and 2b were fixed with screws 3, but it goes without saying that the connecting members 2a and 2b themselves may be clamp members, or that they may be connected using clamp members instead of screws. stomach.

〔Effect of the invention〕

In the image reading device of the present invention, at least two supporting members are connected by a connecting member, and a guide hole for installing a focusing rod lens array is formed so as to eliminate a gap between the supporting members caused by the thickness of the connecting member. It was used. Therefore, the shape of the hole can be formed with higher accuracy than a hole formed by machining. On top of that,
Even with variations in the thickness of the focusing rod lens array, by using a connecting member with a thickness that matches the thickness of the focusing rod lens array to be mounted, the focusing rod lens array can be attached to the guide hole. It is possible to reduce the play when inserting. Therefore, the focusing rod lens array is less likely to bend or collapse, and since the shape of the guide hole is formed with high precision, correction can be easily performed, and the optical system can be easily adjusted.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway simplified perspective view showing an embodiment of the image reading device of the present invention, FIG. 2 is a schematic sectional view showing a conventional image reading device, and FIG. 3 is a schematic cross-sectional view of the support member shown in FIG. FIG. 1a, 1b...Supporting member, 2a, 2b...Coupling member, 5...LED array (light source for illumination), 6...
Image sensor, 8... focusing rod lens array.

Claims (1)

[Scope of Claims] 1. An illumination light source for irradiating light onto a document; a convergent light transmitter that focuses the light reflected by the document; and at least one of the light transmitters that supports the convergent light transmitter. a coupling member thicker than the thickness of the convergent light transmission body; at least two or more supporting members that sandwich the coupling member; and an optical axis or an optical axis of the reflected light focused by the convergence light transmission body. 1. An image reading device comprising: a plurality of photoelectric conversion elements arranged on a line segment connecting . 2. Claim 1, wherein the coupling member includes an elastic body and a pressing member that movably holds the convergent light transmission body in a direction parallel to the optical axis of the reflected light. The image reading device described. 3. The supporting member includes a movable member that presses the focusing light transmitting member through the supporting member for moving the focusing light transmitting member in a direction perpendicular to the optical axis of the reflected light. An image reading device according to claim 1, characterized in that: