JPH03258074A - Close contact type image sensor - Google Patents

Abstract

PURPOSE:To eliminate the need for the fixing after focus adjustment after assembling by adopting a shape of a fiber lens array to be focused in the case of assembling. CONSTITUTION:A slot 111 is formed as a recessed part to a side face of a fiber lens array 11 with respect to a line (a) as a center and a semi-circular projection 121 being a projection is formed to a position being a focus to an original placed to a sensor frame 12 being a read object on an optical axis of a photodetector. The fiber lens array 11 is skided, assembled and fixed in a direction from the front side to the rear side of this paper as shown in figure or in the reverse direction. Thus, the adjustment of the focus and its fixing are implemented simultaneously, the gap is decreased and the process of the lens array installation at the assembling is attained and the manufacture is simplified.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a close-contact image sensor, and particularly to a close-contact image sensor with improved focus adjustment of a converging fiber lens array and means for fixing the same. It is.

[Prior Art] Conventionally, as a document reading device such as a facsimile or a scanner, there is a contact type image sensor which integrates a light source and a lens into a semiconductor image sensor and reads the document in the same size as the document to be read.

FIG. 4 shows a sectional view of this conventional contact type image sensor, FIG. 5 is a partially enlarged view of the device shown in FIG. 4, and FIG. 6 is a top external view.

In FIG. 4, 11 is a convergent fiber lens array, 12 is an image sensor frame, 13 is a screw that fixes the convergent fiber lens array 11, and 14 is an LED array that is a light source, and the light from the 14 light sources is is incident on the document at point b, and the reflected light is focused and received by 15 light receiving sensors as a 1:1 erect image by 11 focusing fiber lens arrays.

Here, in order to combine the reflected light from the original at point b onto the light receiving sensor 15 as an erect image using the focusing fiber lens array 11, the focusing fiber lens array 11 is moved along the reflection optical axis, and the light is received by the focusing fiber lens array 11. It is necessary to adjust the focus of the lens to a position where the image can be formed on the sensor 15, and after adjusting the focus, it is necessary to tighten the focusing fiber lens array with the fixing screw 13 and fix it to the image sensor frame 12. .

[Problems to be Solved by the Invention] As explained above, in the case of the conventional contact type image sensor using a focusing fiber lens array, it is necessary to adjust the focus of the lens array, and furthermore, after the adjustment, There is a problem in that the lens array needs to be fixed, which increases the number of steps.

In addition, in this case, the fiber lens array itself is deformed and the fiber lens array is moved during focus adjustment, so a large gap 16 is created between the fiber lens array 11 and the sensor frame 12, as shown in FIG. 0.5-1. Omm exists, and as shown in FIG. 6, there is a drawback that stray light passes through areas other than those blocked by the fixing screws 13.

[Means and effects for solving the problems] The present invention, as a means for solving the above-mentioned problems, reads an image of an object by using a convergent fiber lens array fixed to an image sensor frame. In a contact type image sensor that reads an image by receiving light on a light receiving sensor, the convergent fiber lens array and the image sensor frame that fixes the convergent fiber lens array, when combined, the convergent fiber lens array The object of the present invention is to provide a contact type image sensor characterized in that the image sensor has a shape that is fixed at a preset position where the focusing fiber lens array is focused.

Further, in a contact image sensor using a focusing fiber lens array, the focusing fiber lens array has a concave portion on a side surface, and an image sensor frame has a convex portion on a side surface that holds the focusing fiber lens array. A contact type image sensor, wherein the convex portion is incorporated into the concave portion to adjust the focus of the convergent fiber lens array; A close-contact image sensor, characterized in that the convex portion is provided at the center of a side surface of the image sensor frame, and the convex portion is provided at a side surface position of the image sensor frame corresponding to a center position of an optical axis between an object to be read and a light receiving sensor. This is an attempt to solve the above problem.

According to the present invention, the shape of the combination is determined in advance so that when the fiber lens array and the sensor frame are combined, the lens array is fixed at a position where the lens array is in focus. Therefore, the focus of the lens array is automatically adjusted simply by combining and fixing the two, and at the same time, the fixing work that was required after adjustment becomes unnecessary.

In addition, with the shape of the above combination, by sliding the convex part of the frame into the concave part of the fiber lens array and fixing it, it is possible to correct the deformation of the fiber lens array itself and easily adjust the focus and fix it at the same time. Moreover, it is also possible to eliminate gaps caused by conventional fixing screws, and to prevent stray light from passing through.

In addition, design and processing can be made easier by creating a concave part in the center of the side surface of the lens array and a convex part in the sensor frame at a position corresponding to the middle of the optical axis of the document to be read and the light receiving sensor. .

[Example] FIG. 1 is a cross-sectional view of a contact type fiber lens array according to an example of the present invention. In the figure, 11 is a converging fiber lens array, and 12 is an image sensor.
is part of the frame.

If the center of the lens array is the a-line, the focal length of the convergent fiber lens array is constant from the a-line in the upper and lower directions in Figure 1, that is, the focal length is the same distance upward and downward from the a-line. A one-to-one erect image can be easily obtained by installing an original to be read and a light-receiving sensor for reading at the position.

Therefore, in this embodiment, a groove 111 is formed as a concave part in the side surface of the fiber lens array 11 with the a-line as the center, and a focal point corresponding to the middle of the original to be read by the sensor frame 12 and the optical axis of the light receiving sensor is set in advance. A semicircular protrusion 121 is formed as a convex portion at a position where the two are aligned. In this example, by sliding the fiber lens array from the front to the back of the paper in FIG. This is what I did. Furthermore, this allows the lens array to be thrown into the assembly process, thereby simplifying the manufacturing process.

In this embodiment, when the length of the convergent fiber lens array 11 is Z as shown in FIG. , width 0. A square groove 111 of 5 mm and depth of 0.5 mm was machined. On the other hand, image sensor frame 1
2, set r≧0.25m at a position that takes into account the focal length in advance.
A semicircular protrusion 121 of m is formed, and during assembly, the fiber lens array 11 is slid in and assembled, and the rectangular groove 111 and the protrusion 121 are pressed and fixed, thereby eliminating focus adjustment work. At the same time, the accompanying work to fix the fiber lens array is no longer necessary.

Furthermore, since the convergent fiber lens array 11 and the image sensor frame 12 are in close contact with each other, there is no gap and it is possible to prevent stray light from passing through.

(Example 2) FIG. 2 is a cross-sectional view of a focusing fiber lens array 11 and a sensor frame 12 showing a second example. In this example, r A semicircular groove 112 of ≧0.25 mm is formed, while a groove 112 with a width of 0.5 mm and a height of 0.5 mm is formed on the frame side 12.
A rectangular protrusion 122 with a diameter of mm is provided, and by combining the two, focus adjustment is not required, and at the same time, the work of fixing the lens is not required.

(Embodiment 3) FIG. 3 is a diagram showing a third embodiment of the present invention, in which the fiber lens array 11 and the sensor frame 12 are similarly
In this embodiment, a V-shaped il! of 90 degrees or more is placed on the same center all of the fiber lens array 11. 113 is processed, and on the frame side 12,
V-shaped protrusion 123 with a sharper angle of 90 degrees or less than the V-shaped 1113
By providing and combining these, focus adjustment work and associated fixing work can be similarly eliminated.

Also in this example, the convergent fiber lens array and the image sensor frame were brought into close contact with each other, thereby making it possible to prevent stray light from passing through.

In the above embodiment, a recess was created at the center of the side of the fiber lens array, but this is not limited to the center of the side, and it can be fixed at a position where the focus is achieved when combined with the frame, and it does not affect the optical axis. It may be at the top or bottom as long as it is not affected.

The same effect can also be obtained by a combination in which a convex portion is formed on the side surface of the fiber lens array and a concave portion is formed on the frame side.

Furthermore, the same effect can be obtained even if the fiber lens array 11 is combined with a frame shaped to wrap around the top and bottom of the fiber lens array 11 within a range that does not affect the optical axis of the fiber lens array 11, without creating special convex and concave parts. be able to.

[Effects of the Invention] As explained above, the contact image sensor of the present invention
The focusing fiber lens array and the sensor frame that fixedly supports it have a shape that, when combined, is fixed at a position where the focal length of the fiber lens array matches. Therefore, the focal length can be adjusted simply by combining and fixing the two, and there is no need to perform focus adjustment and fixing after assembly as in the past.

Therefore, according to the present invention, focus adjustment work can be omitted;
Furthermore, it is possible to simplify the structure by eliminating fixing parts such as screws that are required after adjustment.

Furthermore, the gap that occurs with conventional adjustment work can be eliminated, the deformation of the fiber lens array itself can be corrected, and stray light can be easily prevented.

[Brief explanation of drawings]

FIG. 1 is a sectional view of Example 1 of the present invention. FIG. 2 is a sectional view of Example 2 of the present invention. FIG. 3 is a sectional view of Embodiment 3 of the present invention. FIG. 4 is a cross-sectional configuration diagram of a conventional contact type image sensor. FIG. 5 is a cross-sectional view of a conventional focusing fiber lens array. FIG. 6 is a top external view of a conventional focusing fiber lens array. Figure 111. 12゜13゜14゜15゜11 Focusing fiber lens array image sensor - Frame fixing screw LED array light source light receiving sensor ~ 113. Concave portion (groove) of the focusing fiber lens array Convex portion of the image sensor frame 121~123° Fig. 2 Fig. 3 Fig. 1':)

Claims (3)

[Claims] (1) A contact type image sensor that reads an image of an object by receiving light on a light receiving sensor using a focusing fiber lens array fixed to an image sensor frame, comprising: the focusing fiber lens array and the focusing fiber lens array; an image sensor frame fixing the focusing fiber lens array, when assembled, the image sensor frame fixes the focusing fiber lens array;
A contact image sensor characterized by having a shape that is fixed at a preset position. (2) In a contact image sensor using a focusing fiber lens array, the focusing fiber lens array has a concave portion on a side surface, and an image sensor frame has a convex portion on a side surface that sandwiches the focusing fiber lens array. A close-contact image sensor, comprising: incorporating the convex portion into the concave portion to adjust the focus of the focusing fiber lens array. (3) The concave portion is provided at the center of the side surface of the focusing fiber lens array, and the convex portion is located at a side surface position of the image sensor frame corresponding to the center position of the optical axis between the object to be read and the light receiving sensor. The contact type image sensor according to claim 2, further comprising a contact type image sensor.