JPH11261777A - Picture reader - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a device capable of reducing a manufacturing time and cost by fixing a positioning member with a reference plane becoming fixing reference so as to fix an image sensor chip and a filter glass so as to secure precision for practical use without adjustment of an image sensor or with minimum adjustment of it. SOLUTION: A positioning member with the reference plane becoming the fixing reference is fixed to the substrate so as to fix the image sensor chip and the filter glass. This device is constituted of a lens barrel component 5 mounting a lens 4, the substrate 8 adhered by superposing the filter glass 6 and the sensor chip 7 and the positioning member 10 fixed to the reference position of the substrate 8. Three projections are formed on the lower face of the member 10 and recessed holes corresponding to these projections are formed at the prescribed position of the substrate 8. Then, the blue colored belt 6a of the glass 6 is formed so as to cover a prescribed photodetective element just at the time of matching the reference planes of the glass 6 and the chip 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image reading apparatus having an optical system for reducing an image on a document surface by a reduction optical lens held by a housing and projecting the image on an image sensor fixed on a substrate. In particular, the present invention relates to an image reading device that is effective for a relatively low-resolution use such as a bill validating device and an image reading device for printing on paper.

[0002]

2. Description of the Related Art Conventionally, an image reading apparatus having an optical system for reducing an image on a document surface by a reduction optical lens and projecting the image on an image sensor has been used for an image scanner or a printed matter inspection apparatus.

FIG. 4 conceptually shows such a known image reading apparatus, in which characters written on a document 2 sent by a roller 1 are read by an image reading apparatus 3. As shown in FIG. 5, such an image reading device 3 includes a lens barrel component 5 on which a lens 4 is mounted, a filter glass 6 serving as an optical selection filter and a sensor chip 7 on an upper surface.
And a substrate 8 to which is adhered.

[0006] As shown in FIG.
A large number of light receiving elements 7a and 7b are formed in pairs,
A blue colored band 6 a is formed on the filter glass 6. And the filter glass 6 is, as shown in FIG.
The blue colored band 6a is overlaid so as to cover one of the light receiving elements 7b, and is bonded and integrated with the silicone resin adhesive 9.

In assembling the image reading apparatus having such a structure, first, the image sensor chip 7 is mounted on a reference position of the printed wiring board 8 using an adhesive, and then,
A colored band 6a is put on the image sensor chip 7 so as to cover the light receiving element 7b, and a silicone resin adhesive 9a
After that, the substrate 8 is fitted and adhered to the step inside the lens barrel component 5.

When reducing image data on a document surface and forming an image on the image sensor surface, strict accuracy is required to match the center of the optical axis of the lens with the center of the image sensor.

In such a conventional image reading apparatus, positioning when bonding the sensor chip 7 to the substrate 8 and positioning when bonding the filter glass onto the sensor chip 7 are difficult. In short,
There has been a problem that the displacement between the light receiving element and the colored portion of the filter glass often occurs.

On the other hand, in an image reading apparatus including an image sensor using a reduction optical lens, such as an image scanner or a printed matter inspection apparatus, when image data on a document surface is reduced to form an image on the image sensor surface. In order to match the center of the optical axis of the lens with the center of the image sensor and to support and fix each of the lens and the image sensor, strict accuracy is required.For this reason, conventionally, when fixing the image sensor chip to the substrate, It is necessary to fix while monitoring the image sensor pixel position with respect to the mounting reference position, or to adjust the image sensor position when mounting the image sensor to the housing that fixes the lens,
There has been a problem that the image reading device obtained due to the adjustment work and the use of the expensive adjustment device is expensive.

[0009]

As described above, in the conventional image reading apparatus, positioning for bonding the sensor chip to the substrate and positioning for bonding the filter glass on the sensor chip are difficult. In addition, it takes a long time, and there is a problem that a misalignment occurs between the light receiving element and the colored portion of the filter glass, resulting in a defective product, thereby increasing the manufacturing cost.

The present invention has been made in order to solve such a conventional problem, and it is easy to perform a positioning operation when fixing an image sensor chip to a substrate and a positioning operation when fixing a filter glass onto a sensor chip. It is an object of the present invention to provide an image reading apparatus in which there is no displacement between a light receiving element and a colored portion of a filter glass.

[0011]

According to the present invention, there is provided an image reading apparatus having an optical system for reducing an image on a document surface by a reduction optical lens held by a housing and projecting the image on an image sensor fixed on a substrate. In the apparatus, the substrate has a positioning member having at least one reference surface serving as an attachment reference for attaching an image sensor chip to a reference position on an optical axis of the reduction optical lens, and the image sensor chip has the reference member. At least one side of the positioning member is abutted against a reference surface of the positioning member when the positioning member is attached to the position, and is fixed to a reference position on the substrate.

According to the present invention, there is provided an image reading apparatus having an optical system for reducing an image on a document surface by a reduction optical lens held by a housing and projecting the reduced image onto an image sensor fixed on a substrate via a filter. In the apparatus, the substrate has a positioning member having at least one reference surface serving as an attachment reference for attaching an image sensor chip and a filter at a reference position on an optical axis of the reduction optical lens, and the image sensor chip and When the filter is attached to the reference position, at least one side thereof is abutted against a reference surface of the positioning member and is fixed so as to overlap the reference position on the substrate.

The positioning member has an L-shape or a U-shape, and is fixed at a predetermined position on the substrate or detachably fixed at a predetermined position on the substrate.

By appropriately setting the thickness of these positioning members, the inside of the L-shaped or U-shaped positioning member is used as a reference surface for positioning the image sensor chip and the filter. In addition, a reference surface is formed by a rib or the like at an appropriate position inside the lens barrel component, and the reference surface is brought into contact with the outside of the L-shaped or U-shaped positioning member so that the lens barrel component and the substrate Positioning may be performed.

[0015]

[Operation] After the positioning member is fixed at the reference position of the substrate, the sensor chip is inserted from the front of the opening of the positioning member to the back of the positioning member so that the front edge slides on the substrate, and then presses down on the substrate when it stops. And fix it.

The filter glass is also inserted into the positioning member so that the front edge slides over the sensor chip from just before the opening of the positioning member, and is fixed when it stops.

According to the present invention, since the positioning member having the reference surface serving as the mounting reference is attached to the substrate to fix the image sensor chip and the filter glass, an adjusting operation and an expensive adjusting device are not required.

[0018]

Embodiments of the present invention will be described below in detail with reference to the drawings. In the drawings, the same portions are denoted by the same reference numerals. Further, the present invention may be modified in the following embodiments without departing from the gist thereof.

In this embodiment, as shown in FIG. 1, a lens-barrel component 5 having a lens 4 mounted thereon, a substrate 8 on which a filter glass 6 and a sensor chip 7 are laminated and bonded,
The positioning member 10 is attached to the reference position.

As shown in FIG. 2, three projections 11, 11, 11 are formed on the lower surface of the positioning member 10, and concave holes corresponding to these projections 11,. 12, 12, 12 are formed.

The lens barrel part 5 is entirely made of a plastic injection-molded product, and comprises a lens barrel part 5a and a housing part 5b. A slit through which light passes is formed at the top of the lens barrel 5a, and the lens 4 is inserted into the rear side of the slit and fixed by a holding component. The back side of the edge of the housing 5b is a flat surface and serves as a reference surface for positioning.

The front edges and both side surfaces of the filter glass 6 and the sensor chip 7 are also flat surfaces and serve as reference surfaces for positioning. Then, the filter glass 6 and the sensor chip 7
When the reference planes are matched, the blue colored band 6a of the filter glass 6 is formed so as to cover the predetermined light receiving element 7b.

The projection 11 of the positioning member 10 is fitted and fixed in the concave hole 12 of the substrate 8, and the positioning member 1
When the image sensor chip 7 is brought into contact with the inside of the lens 0, the lens 4 forms an image on the light receiving element of the image sensor chip.

Although not shown, the wiring pattern terminals are formed on the substrate 8 at positions where the sensor chip 7 can be bonded when the sensor chip 7 is positioned by the positioning member 10.

In the drawing, A indicates a reference plane for positioning with respect to the image sensor chip, and B indicates a reference plane for positioning the lens barrel component.

The image reading apparatus of this embodiment is assembled as shown in FIG.

First, the projection 11 of the positioning member 10 is inserted into the concave hole 12 of the substrate 8 to fix the positioning member 10 on the substrate 8 (a).

Next, a thermosetting adhesive 9 is applied to the back surface of the sensor chip 7 in a dot-like manner, and the front edge of the sensor chip 7 is slid on the substrate 8 from just before the opening of the positioning member 10. The sensor chip 7 is adhered to the substrate 8 so that the sensor chip 7 is pressed down onto the substrate 8 when the positioning member 10 is stopped until the sensor chip 7 comes into contact with the inside of the positioning member 10 (b). A thermosetting adhesive is applied to the back surface of the driving IC chip 13 in a dot-like manner and fixed at a predetermined position on the substrate (c). Bonding connection is performed (d).

Further, a silicone resin adhesive 9a is attached to the back surface of the filter glass 6 in a dot-like manner,
0 is inserted from the front side to the back side of the opening portion of the opening until it comes into contact with the inside, and when it stops, it is pressed down onto the sensor chip 7 and adhered. Finally, resin potting 14 is applied on the bonding wire to complete the image reading apparatus ( e).

In the above embodiment, an example in which a U-shaped positioning member is used has been described. However, an L-shaped positioning member may be used.

It is also possible to position the lens barrel component by using the outside of these positioning members.

[0032]

According to the present invention, practical accuracy can be secured with no adjustment or minimum adjustment of the image sensor chip, and a reduction in manufacturing time and cost can be realized. This is effective as a low-resolution image reading device such as a printing paper device.

[Brief description of the drawings]

FIG. 1 is an exploded view of an embodiment of the present invention.

FIG. 2 is an exploded view of a main part of one embodiment of the present invention.

FIG. 3 is a view showing an assembling state of one embodiment of the present invention.

FIG. 4 is a diagram conceptually showing an image reading apparatus.

FIG. 5 is an exploded view of a conventional image reading apparatus.

FIG. 6 is a diagram illustrating a positional relationship between a light receiving element and a filter glass of the image reading apparatus.

FIG. 7 is a cross-sectional view illustrating a configuration of the image reading apparatus.

[Explanation of symbols]

1 ... roller, 2 ... original, 3 ... image reading device, 5 ...
... lens barrel parts, 6 ... filter glass, 6a ... colored band,
7 ... Sensor chip, 7a, 7b ... Light receiving element, 8 ...
Substrate, 9: thermosetting adhesive, 9a: silicone resin adhesive, 10: positioning member, 11: protrusion, 12 ...
Hollow

Claims (4)

[Claims] 1. An image reading apparatus having an optical system for reducing an image on a document surface by a reduction optical lens held by a housing and projecting the image on an image sensor fixed on the substrate, wherein the substrate is A positioning member having at least one reference surface serving as an attachment reference for attaching the image sensor chip to a reference position on the optical axis of the reduction optical lens,
The image reading device according to claim 1, wherein the image sensor chip is fixed to a reference position on a substrate by attaching at least one side thereof to a reference surface of the positioning member when attaching the image sensor chip to the reference position. 2. An image reading apparatus having an optical system for reducing an image on a document surface by a reduction optical lens held by a housing and projecting the reduced image on an image sensor fixed on a substrate through a filter. A substrate having a positioning member having at least one reference surface serving as a mounting reference for mounting an image sensor chip and a filter at a reference position on the optical axis of the reduction optical lens, wherein the image sensor chip and the filter have the reference position; An image reading device, wherein at least one side of the positioning member is abutted against a reference surface of the positioning member when the positioning member is attached to the position, and is superposed and fixed at a reference position on a substrate. 3. The image reading apparatus according to claim 1, wherein the positioning member has an L-shape or a U-shape. 4. The housing has at least one reference surface serving as an attachment reference for attaching to the substrate, and the housing projects the reference surface outward from the positioning member when the housing is attached to a reference position of the substrate. 4. The image reading device according to claim 3, wherein the image reading device is fixed at a reference position on the substrate.