JPH0575796A - Picture reader - Google Patents

Abstract

PURPOSE:To obtain the adjustment of an image sensor and its mount method in which the adjustment time is reduced without an error in adjustment in the picture reader and the cost is reduced. CONSTITUTION:An image sensor 1 is supported by an adjustment jig at assembling to make optical adjustment while keeping non-contact with a main body, a member 5 burying the image sensor 1 and the main body are inserted into the holes 3a, 3b of the support member 3 after the adjustment and fixed by soldering.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device structure of an image reading device.

[0002]

2. Description of the Related Art Generally, in an image reading section such as an image scanner, a so-called 1: 1/2 optical system in which a document placed on a platen glass is scanned by a light source and a mirror to expose it on an image sensor or a photoconductor. Has been adopted. As shown in FIG. 7, the 1: 1/2 optical system uses the original P on the fixed original glass 100 as the light source 1.
The image light reflected by the mirrors 102, 103, 104 is imaged on the image sensor 106 or the like by the imaging lens 105. A lamp unit 107 including a light source 101 and a mirror 102, and
Mirror unit 108 including mirrors 103 and 104
Along the guide rail provided on the base frame 109 is 1: 1 / by the power from a drive source (not shown).
The range of the platen glass 100 is scanned at a speed ratio of 2. The imaging lens 105 and the image sensor 10
6. The drive source is fixedly mounted on the base frame 109. The image read by the image sensor 106 is amplified by the amplifier 110, converted into a digital value by the A / D converter 111 and sent to the image processing circuit 112, where image processing such as binarization and γ conversion is performed. After that, it is transmitted to the external device 120 such as a personal computer through the interface circuit 113. (See Figure 8)

[0003]

FIG. 9 is a schematic drawing (developing folding by a mirror) of a state where an image on a line currently being read on a document surface is formed on an image sensor. It is a thing. In order to obtain the best image with the image sensor, it is necessary to precisely perform optical adjustment in the five directions as described below. That is, the image sensor light-receiving surface 106a is placed parallel to the document surface P (rotation in the θ direction in the drawing), the image sensor light-receiving surface 106a is arranged at the in-focus position of the lens 105, and the magnification is adjusted to a regular value. (Image sensor 10 in the figure
6 and movement of the lens 105 in the Y direction), and placing the image sensor light-receiving surface 106a on the plane formed by the reading line P1 and the optical axis 105a of the lens (rotation of the image sensor 106 in the ψ direction and movement in the Z direction). , Adjusting the reading start position in the main scanning direction (Image sensor 1 in the figure
06 movement in the X direction).

By the way, the pixel of the image sensor used in such an optical system has a side length of about 10 μm, and the depth of focus of the lens is a very small value of tens of μs to hundreds of μs. Will shift to. Therefore, each of the above adjustments is performed while holding the image sensor (the component equipped with it) with a jig and keeping it in non-contact with the device. Finally, the structural member on the device main body and the image sensor or its holding member are adjusted. The applicant is making the proposal of filling the gap with solder at the same time.

Although the number of parts can be greatly reduced by this proposal, a large amount of solder is required to fill the gap between the members with solder, or when the gap is large, the gap is filled with solder. Can't
Parts to be joined with solder (holding member for image sensor)
However, there is a new problem that the solder is badly glued and takes a long time because it is made of a metal having a large heat capacity such as a metal plate, and eventually contracts while the solder cools and misaligns.

[0006]

The present invention is intended to solve the above-mentioned problems, and an image light obtained by illuminating an original is imaged on an image sensor by an image forming means to form an image on the original. In an image reading apparatus for reading an image, optical adjustment is performed so that an image on a document can be correctly read while the image sensor is kept in non-contact with the apparatus main body, and after the adjustment, the image sensor or a member supporting the image sensor and the apparatus main body are provided. The member for filling the gap is fixed to the image sensor or the member for supporting the image sensor and the apparatus main body, thereby ensuring the mounting position of the image sensor to the apparatus main body.

[0007]

Embodiment 1 FIG. 1 shows a first embodiment of the present invention, in which an imaging lens, an image sensor and their surroundings are depicted. In the figure, 1 is an image sensor, 1a is a light receiving surface of the image sensor, 2 is a printed circuit board on which the image sensor and its peripheral circuits are mounted, and 3 is a holding member of the image sensor fixed on the main body 10. 2 can be supported at multiple locations. Since this member is soldered, it is made of a steel plate or the like plated with tin or the like, which is easy to solder. Between the printed circuit board 2 and the holding member 3, there is a gap necessary for adjustment. The portions 2a to 2d of the printed circuit board 2 facing the holding member 3 have the ground pattern of the circuit, and the resist is peeled off only from this portion to expose the copper foil. Further, holes 3a and 3b are provided at positions of the holding member 3 facing the printed circuit board 2. 4 is
This is a lens for forming the reflected light of the image on the document on the image sensor.

Printed circuit board 2 on which an image sensor is mounted
Is held by the claw portion C of the adjusting jig. The claw portion of the adjustment jig is moved or rotated in a total of five directions in the X, Y, Z, θ, ψ directions by the stage provided on the main body (not shown) of the adjustment jig (see the conventional example). (See section) is possible.
The imaging lens 4 is supported by a lens holder 6 so as to be movable in the Y direction, and after adjustment, is fixed to the main body 10 by screwing or the like.

The image sensor and the lens are adjusted in each of the above directions while observing the image read by the image sensor on the adjustment chart provided on the adjustment jig at a position corresponding to the document surface of the apparatus. When the adjustment in all directions is completed, the wedge-shaped member 5 is attached to the hole 3a of the holding member 3 while the image sensor is held by the adjustment jig.
Insert in 3b. The member 5 falls by its own weight until the inclined surface 5a contacts the end surfaces of the holes 3a and 3b. At this time, the surface 5b opposite to the inclined surface of the member 5 is in contact with the copper foil portions 2a to 2d of the printed board 2 (see FIG. 2).

Subsequently, soldering work for fixing the printed circuit board 2 to the holding member 3 is performed. Joints between the printed circuit board 2 and the member 5, that is, 2a to 2d and 5b, and joints between the member 5 and the holding member 3, that is, 5a and 3a,
The printed circuit board 2 is securely fixed to the holding member 3 by soldering the printed circuit board 2 and 3b. At this time, since the gap between the printed circuit board 2 and the holding member 3 is filled with the member 5, there is no difference in adjustment due to contraction due to cooling of the solder unlike the conventional example. In addition, since the amount of solder used for joining is greatly reduced, there are advantages that work time is shortened and exhaust equipment can be simplified.

In this embodiment, the method of fixing the printed circuit board to the holding member has been described, but the image sensor itself may be fixed to the holding member.

Embodiment 2 As described in the previous embodiment, the time required for soldering after the adjustment affects the time required for assembling the apparatus, but this is largely influenced by the soldering of the parts to be joined. It is easy to climb. The factors that determine the ease of soldering are mainly the volume of parts and surface treatment. In this respect, electrical components, that is, components mounted on an electric circuit board, have a small volume and are often plated with gold or solder.
It can be said that it has an ideal shape.

The embodiment shown in FIGS. 3 and 4 uses a commercially available electric component in the portion to be joined by solder in the above-mentioned embodiment. In the figure, parts having the same functions as those of the previous embodiment are given the same numbers.

Reference numeral 11 in the drawing denotes a jumper pin used for short-circuiting a portion which cannot be connected by a pattern on the circuit board. A plurality of jumper pins 11 are soldered to the support member 3 in advance, and this is mounted on the main body 10. 12 is also a jumper pin,
It is soldered on the substrate 2 on which the image sensor 1 is mounted.

Reference numeral 13 is a component that replaces the member 5 used to fill the gap between the printed circuit board 2 and the holding member 3 in the previous embodiment, and uses a check terminal. Check terminal 13 has jumper pins 11 and
It depends on both twelve. Therefore, the printed circuit board 2
Has a degree of freedom corresponding to the inner diameter of the check terminal 13 with respect to the holding member 3, and this is an adjustment margin in five directions. The adjustment jig and the adjustment procedure are the same as those in the previous embodiment.

After the adjustment is completed, the check terminal 13 is soldered to each of the jumper pins 11 and 12. Since the check terminal 13 is in contact with both the jumper pins 11 and 12, the printed board 2 and the holding member 3 can be fixed to each other without misalignment by soldering these contacts.

By adopting this embodiment, workability can be improved and cost merit can be expected by using commercially available mass-produced parts.

In the present embodiment, for the sake of simplification of description, an electric component which is actually on the market is used. However, a component having a performance equivalent to this is prepared according to the form of the apparatus. Has the same effect.

Embodiment 3 In the above-mentioned two embodiments, the description has been made based on the apparatus configuration in which the optical adjustment is performed in the assembly process of the main body. By the way, some image reading apparatuses of this type have a configuration in which a lens and an image sensor are combined into a single unit, which is optically adjusted before being incorporated into the apparatus main body. Such a configuration has the advantage that the load on the main assembly line is reduced in the assembly process, and in terms of the service system, if the image sensor fails, it can be repaired simply by replacing the unit. is there.

In this embodiment, a structure corresponding to such unitization will be described with reference to FIG. In the figure, parts having the same functions as those of the previous embodiment are given the same numbers.

In the above embodiment, the holding member 3 of the image sensor has a shape in which the front side thereof is extended and the lens 4 can be held. Reference numeral 3c is a guide groove for slidably supporting the lens 4 in the optical axis (Y-axis) direction, 3d is a screw for fixing the lens, 3e and 3f are positioning holes for setting on the main body and the jig.

This unit is placed on the unit adjusting jig, and adjustment in five directions and attachment of the image sensor substrate 2 to the holding member 3 are performed. An adjustment chart is provided at a position of the unit adjustment jig corresponding to the document surface of the apparatus, and the image is read by an image sensor to perform optical adjustment. The holding part of the image sensor board 2 of the adjustment jig,
The stage in five directions, the adjusting method, and the fixing of the image sensor substrate 2 and the holding member 3 are the same as those in the above-described embodiment.

After the adjustment and installation are completed, this unit is mounted on the unit mounting portion of the main body with reference to the positioning holes 3e and 3f.

According to this configuration, in addition to the advantages on the assembly line and the service system as described above, it is possible to avoid an increase in the number of parts that tends to occur when unitizing.

Embodiment 4 A color reading device is a development of the image reading device. Although there are various methods of color separation in a color reading device, there is a method using an image sensor in which a plurality of line sensors each having a color filter on the surface are housed in one package.

FIG. 6 shows a sensor of a color document reading apparatus using such an image sensor and its peripheral portion.
As shown in the figure, this apparatus requires rotation adjustment in the η direction in order to make the plane formed by the plurality of image sensors (1a to 1c) parallel to the document surface, in addition to the adjustment described above. Become.

When the present invention is applied to this reading device,
It is possible to deal with this by simply adding a new rotating stage in the η direction on the adjusting jig in addition to the above-described embodiments without causing any change such as addition of parts to the apparatus main body.

The present invention can be implemented not only in the above-mentioned line sensor but also in an apparatus using an area sensor.

Furthermore, in the above description of the embodiments, soldering is used to fix the members, but
A fixing means such as adhesion or welding can also be adopted.

[0030]

By implementing the present invention, the assembly and adjustment time of the image sensor can be greatly shortened and the adjustment error due to soldering, which has been a problem in the past, can be completely eliminated.

[Brief description of drawings]

FIG. 1 is a diagram for explaining a first embodiment of the present invention.

FIG. 2 is a detailed view of a joint portion according to the first embodiment of the present invention.

FIG. 3 is a diagram for explaining a second embodiment of the present invention.

FIG. 4 is a detailed view of a joint portion according to the second embodiment of the present invention.

FIG. 5 is a diagram for explaining a third embodiment of the present invention.

FIG. 6 is a diagram for explaining a fourth embodiment of the present invention.

FIG. 7 is a schematic configuration diagram of a conventional image reading apparatus.

FIG. 8 is a processing block diagram of the image reading apparatus.

FIG. 9 is an optical path development view of the image reading apparatus.

[Explanation of symbols]

 1 image sensor 2 printed circuit board 3 image sensor holding member 4 lens

Claims (6)

[Claims] 1. An image reading device for reading an image on a document by forming an image light obtained by illuminating a document on the image sensor by an image forming means, the image sensor being brought into non-contact with the device body. Optical adjustment is performed so that the image on the original can be read correctly, and after the adjustment, the image sensor or the member that fills the gap between the member supporting the image sensor and the main body of the device is the image sensor or the member supporting the device. An image reading device, which secures an attachment position of an image sensor to a device body by fixing the image sensor to each of the body. 2. The image reading apparatus according to claim 1, wherein the image sensor or a member for filling a gap between the apparatus supporting the image sensor and the apparatus main body has a shape capable of filling the gap by its own weight. .. 3. The image reading apparatus according to claim 1, wherein the image sensor or a member that fills a gap between the apparatus supporting the image sensor and the apparatus main body is fixed by soldering. 4. The image reading apparatus according to claim 1, wherein the image sensor or a member that fills a gap between the image sensor or a member supporting the image sensor and the apparatus main body is fixed by adhesion. 5. The image reading apparatus according to claim 1, wherein the image sensor or a member that supports the image sensor and a member that fills a gap between the apparatus main body are fixed by welding. 6. The joint between the image sensor or a member that supports the image sensor and a member that fills a gap between the apparatus main body and a member that fills the gap are members having a small volume and subjected to surface treatment. The image reading device according to claim 3.