JPH05145698A - Image sensor - Google Patents

Abstract

(57) [Summary] (Correction) [Purpose] In an image sensor including a first frame and a second frame, the force of deforming outward in the first frame that presses and fixes the optical system is supported to prevent the deformation. To prevent. In an image sensor including a first frame 1 and a second frame 2, a deformation of the first frame is prevented on a side that is located on the second frame and at least presses and fixes the optical system 5 of the first frame. Protrusions A are provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image sensor suitable for use in an image information processing device or the like.

[0002]

2. Description of the Related Art A conventional so-called contact type image sensor has a structure as shown in FIGS.
The first frame 1 and the second frame 2 are divided. A space is provided in the first frame 1 so as to be divided into two in the longitudinal direction of the side surface, and the original surface 9 on the cover glass 3 is imaged on the light receiving element array 6 in the first space (recess) 1A. The optical system (imaging element array, for example, a short focus gradient index rod lens array) 5 for
It is fixed by. The first space 1A is formed in a recess, the optical system 5 is pressed and fixed in the X direction by the set screw 11, and the tip of the set screw 11 (hence,
A predetermined set width t is provided on the side surface of the optical system 5) and the space forming surface of the first frame 1.

A second space 1B is provided next to the first space 1A (on the left side in FIG. 6), and a light source 4 for illuminating a document is held therein. The light from the light source 4 must accurately illuminate the position on the image for reading provided on the document surface 9 on the cover glass 3, and therefore, the second space 1B is provided with an inclined portion, and this inclination is By utilizing it, the light source 4 can be fixed to the second space 1B in the first frame to irradiate a predetermined position.

Further, a slit 12 which is an optical path is formed between the optical system 5 and the light receiving element array 6 so as to hollow out the first frame. Therefore, an image of the original surface 9 illuminated by the light from the light source 4 is formed. Through the optical system 5 through the slit 12
An image is formed on the light-receiving element array 6 through the optical path, and photoelectric conversion is performed here.

On the other hand, the light receiving element array 6 is provided at a position on the substrate 7 for transmitting an electric signal so that the image of the original surface 9 is accurately formed through the slit 12, and the array 6 and the substrate 7 are slit. While being held in the third space (recess) 1C of the first frame 1 provided on the lower side of the second frame 12,
It is supported by the frame 2 via the rubber 8 for preventing the positional displacement utilizing the cushioning action.

A second frame is attached to the first frame 1 by a connecting screw 10.

[0007]

However, in the image sensor having such a conventional structure, the first frame 1
The second frame 2 and the second frame 2 are fixed by a plurality of coupling screws 10 at positions in two rows in the longitudinal direction, and the optical system (imaging element array) 5 that is pressed and fixed to the first frame 1 includes the first frame 1 and the second frame 2. It is fastened and fixed in a plurality of positions from the side in the X direction shown in FIG. Therefore, a force in the direction opposite to the X direction acts on the tightening side surface of the first frame 1, and when the force in the opposite direction cannot be supported by the tightening side surface of the first frame 1, the side surface bulges. Therefore, there is a problem that the gap between the optical system 5 and the first frame 1 becomes larger than the set value t. As a result, (1) light (stray light) from the gap t enters the light-receiving element array 6 and adversely affects the read image. That is, when a document is read with multiple gradations, it is not possible to correctly read the light and shade due to the effect of stray light, and the information that should be read as black is determined to be gray.

(2) As a result of the set value t becoming large, it becomes difficult to standardize the external dimensions of the side surface of the first frame 1, and adjustment is required to determine the mounting space for the image sensor.

(3) The deformation of the side surface of the first frame 1 makes the positioning of the light receiving element array 6 unstable and the reading position of the original 9 also unstable, so that the area where the original 9 is brought into close contact with the cover glass 3 is long. If you do not take it, "document floating" will occur.

An object of the present invention is to solve the problem caused by such a conventional structure, and even if the optical system is clamped and fixed on the frame, the outer dimensions of the frame are not deformed, and an accurate image can be read, and An object of the present invention is to provide an image sensor whose mounting space can be easily determined.

[0011]

In order to achieve such an object, the present invention provides a light receiving element for performing photoelectric conversion, an optical system for forming an image of an original surface on the light receiving element, and a light source for illuminating an original. And at least a first frame to which the optical system is pressed and fixed, and a second frame attached to the first frame, which is located on the second frame,
It is characterized in that at least a side of the first frame where the optical system is pressed and fixed is provided with a protruding portion for preventing deformation of the first frame.

[0012]

According to the present invention, by providing the protrusion on the second frame 2 at least on the side for pressing and fixing the optical system to prevent the deformation of the frame, the force in the opposite direction for tightening and fixing the optical system, That is, it is possible to support the force that deforms the frame outward by this protruding portion.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. The same members as those of the conventional example are designated by the same numbers,
A duplicate description will be omitted.

FIG. 1 shows a first embodiment of the present invention, in which a protrusion A for supporting the force of the first frame 1 attempting to deform outward is provided with an optical system 5 on the second frame 2. Is provided only on the side of the first frame 1 that is pressed and fixed to the first frame 1. In addition, the protruding portion A has an L shape and is provided in the longitudinal direction on the pressing and fixing side.

In this embodiment, the first frame 1 and the second frame 2 are fixed on the opposite side to the side where the optical system 5 is pressed and fixed by a plurality of coupling screws 10 in the longitudinal direction as in the conventional example. .

FIG. 2 shows a second embodiment of the present invention, in which the protruding portion A is formed in a U shape and the second
It is provided on both sides of the frame 2, and the connecting screw is abolished. This is because the protruding portion A of the second frame 2 has a U-shape, and the protruding portion A has a function of preventing the protruding portion A from being deformed to the outside of the first frame 1 and combines the first frame 1 and the second frame 2 with each other. This is because it has become possible to add the function to do. Further, FIG. 3 shows a third embodiment of the present invention, in which the protruding portion A is formed in a dovetail groove shape. Also in this embodiment, as in the case of the second embodiment, the protruding portion A has the second
It is provided on both sides of the frame 2, and the connecting screw is abolished. This is because, like the second embodiment, the protrusion A in this embodiment also has the above-mentioned two functions.

Further, FIG. 4 shows a fourth embodiment of the present invention, in which the protruding portion A is formed in an uneven shape and is provided on both sides of the second frame 2 and the first frame 1 A coupling screw 10 is also used to fix the second frame 2 and the second frame 2. This is nothing but the fact that the screw 10 compensates for the insufficient engagement of both frames, as in the first embodiment.

In the above-described four embodiments, the optical system 5 is provided by providing the second frame 2 with the protrusion A.
Even if is fixed by pressing it against the first frame 1 with the set screw 11, the tightening and fixing direction (X
Direction), the force that tends to deform outward is supported by the protrusion A, and the first frame 1 does not deform outward, so it is provided between the first frame 1 and the optical system 5. The set value t of the gap is always kept constant.

In the present invention, the second frame 2
It is not always necessary to provide the protrusions A provided on the both sides of the second frame 2, but it is sufficient to provide the protrusions A on at least the side surface where the optical system 5 is pressed and fixed to the first frame 1 with the set screw 11. Of course, the first frame 1 and the second frame 2
Depending on the shape of the protruding portion A, the connecting screw 10 may not be used together for fixing.

Further, the protruding portion A in the second frame 2
May be formed on the entire surface in the longitudinal direction, or may be formed by selecting a plurality of places (at least both ends in the longitudinal direction).

Further, here, the shape of the protruding portion A is shown in FIGS. 1 to 4, but the shape is not limited to these shapes, and is generated by the first frame 1 pressing and fixing the optical system 5. It goes without saying that all that support the force that deforms outward (force in the direction opposite to the X direction) are included.

[0022]

As is apparent from the above description, according to the present invention, the projection portion A provided on at least the side on which the optical system 5 is pressed and fixed on the second frame 2 allows the first frame 1 to be optically coupled. A force (X) in the opposite direction to the force (X) for pressing and fixing the system 5 can be supported, and the gap between the optical system 5 and the first frame 1 can be set to a predetermined value. It is possible to hold the value t.

Therefore, stray light does not enter the light receiving element array 6 and does not adversely affect the read image, so that the image quality can be maintained.

Further, the external dimensions of the image sensor can be standardized and the mounting on the apparatus becomes easy.

Further, since the external dimensions of the image sensor are not deformed, the optical path length between the image reading position and the light receiving element array 6 can be kept constant, and the quality of the image sensor can be stabilized and the reliability can be improved. .

It is needless to say that the number of man-hours and the cost can be reduced in manufacturing the image sensor because the connecting screw 10 can be reduced or eliminated for fixing the first frame 1 and the second frame 2.

[Brief description of drawings]

FIG. 1 is a side sectional view showing a first embodiment of the present invention.

FIG. 2 is a side sectional view showing a second embodiment of the present invention.

FIG. 3 is a side sectional view showing a third embodiment of the present invention.

FIG. 4 is a side sectional view showing a fourth embodiment of the present invention.

FIG. 5 is an overall perspective view showing the internal structure of a conventional image sensor.

FIG. 6 is a side sectional view showing a conventional image sensor.

[Explanation of symbols]

 1 1st frame 2 2nd frame 4 Light source 5 Optical system (imaging element array) 6 Light receiving element array A Projection part

Claims (1)

[Claims] 1. A light receiving element for performing photoelectric conversion, an optical system for forming an image of an original surface on the light receiving element, a light source for illuminating an original, and a first frame at least to which the optical system is pressed and fixed. A second frame attached to the first frame, the protrusion being located on the second frame and preventing deformation of the first frame at least on a side of the first frame where the optical system is pressed and fixed. An image sensor characterized by having a section.