JPH03225318A - Image forming device - Google Patents

Abstract

PURPOSE:To eliminate the warpage and stray light of an optical member and to facilitate the assembly by partitioning a holder into plural opening parts, inserting an image forming element, abutting its roof part on an internal end wall and fixing the element. CONSTITUTION:The image forming element 12 of a copying machine, etc., is formed integrally with optical components such as an object-side lens part 16, an image-side lens part 18, reflecting surfaces 24 and 26. Then the holder 14 where the image forming element 12 is stored is partitioned by a partition wall 40 into the opening parts 42, which are respectively formed of a main hole part 42a and a subordinate hole part 42b. In this constitution, the roof part 28 of the image forming element 12 is inserted into the subordinate hole part 42b of the holder 14 and the tip end surface of the roof part 28 is made to abut on the internal wall end 44 of the holder 14, thereby fixing the element 12 to the holder 14. Therefore, no unreasonable force is applied to the image forming element 14 where no warpage is generated. Further, the stray light and flare are precluded and the assembly is facilitated.

Description

[Detailed Description of the Invention] [Summary] Regarding an imaging device for image reading and image formation in copying machines, optical printers, facsimiles, etc., there is no warping of optical members and the generation of stray light and flare light is prevented. However, the purpose is to provide an imaging device that is easy to assemble and does not impose undue stress on the imaging element. further comprising: an integrally structured imaging element configured to reflect the reflected light from the roof part toward the image-side lens part on a second reflecting surface; and a holder accommodating a plurality of the imaging elements; The holder has a plurality of openings partitioned by partition walls, and each opening has a main hole having a cross-sectional shape that matches the contours of the object-side lens part and the image-side lens part, and a cross-section capable of accommodating a roof part. The image forming element is fixed to the holder by bringing the tip end surface of the roof portion of the imaging element into contact with the inner end wall of the sub hole.

[Industrial application field]

The present invention relates to an imaging device for reading images in copying machines, facsimiles, etc., and forming images in optical printers, etc.

Copying machines and optical printers are capable of reading and forming images on the entire surface of a paper by scanning. In scanning, light from a document, an LED chip, etc. is read and an image thereof is formed on a copy paper or the like. Each imaging element is composed of a combination of lenses and prisms to obtain a Royal life-size image. The lenses and prisms used in such an imaging device are very small, and the number of lenses and prisms as a whole is quite large, so it is advantageous to form such lenses and prisms as integrally as possible.

[Conventional technology]

As a proposal to integrate lenses and prisms as much as possible, Japanese Patent Application Laid-Open No. 58-44416 proposes, for example, a lens array formed by integrally arranging only lenses with the same function of each imaging element, and a lens array with the same function. This disclosure discloses forming a prism array by arranging prisms having a similar shape integrally in a row, and inserting the prisms into a holder. Furthermore, JP-A No. 61-210319 goes one step further by arranging only lenses and prisms with the same function in a row, and using a two-dimensional distribution in which such arrays are arranged in rows. It discloses that the prisms and prisms are integrally formed.

[Problem to be solved by the invention]

As mentioned above, lens arrays and prism arrays formed by integrally arranging components with the same function of each imaging element using resin materials, as well as integral structures in which all lenses and prisms are distributed two-dimensionally, Although it has the advantage of being easy to handle and assemble, it has a plate-like structure, with thick and thin parts appearing within the plate-like shape, so it is difficult to use resin materials. There was a problem in that warpage was likely to occur after molding. For this reason,
It is necessary to correct warpage during assembly and use, which puts stress on the structure and causes cracks to occur. Moreover, if the assembly is performed while correcting the warpage, minute positional deviations are likely to occur, making the assembly work troublesome. Furthermore, in the structure in which all lenses and prisms are integrally formed as described in JP-A-61-210319, light leaks between one imaging element and an adjacent imaging element. It is necessary to block the light so that it does not occur, and for this purpose, unnecessary material parts between one imaging element and the adjacent imaging element are removed. As the thickness changes greatly, warping becomes more likely to occur during molding. In a structure in which all lenses and prisms are integrally formed, not only will warpage occur, but simply removing unnecessary material will generate a considerable amount of stray light and flare light, causing ghosts and image distortion. There was a problem in that the contrast of the image was reduced.

SUMMARY OF THE INVENTION An object of the present invention is to provide an imaging device that does not warp an imaging element, does not apply unreasonable stress to the imaging element, prevents the generation of stray light or flare light, and is easy to assemble. .

[Means for Solving the Problems] An imaging device according to the present invention includes an object-side lens section and an image-side lens section that face each other with an interval between them, and an integrated structure between the object-side lens section and the image-side lens section. a first optical path portion and a second optical path portion each having a first reflective surface and a second reflective surface;
an optical path section, and a roof section formed along the first optical path section and the second optical path section, and reflects incident light from the object-side lens section toward the roof section at the first reflecting surface. an integrally structured imaging element configured to further reflect the reflected light from the roof part toward the image-side lens part on the second reflective surface, and a holder that accommodates a plurality of the imaging elements. An imaging device, wherein the holder has a plurality of openings partitioned by a partition wall for individually inserting the imaging elements, and each opening has a plurality of openings separated by the object-side lens part and the image-side lens part. The main hole has a cross-sectional shape that matches the contour of the roof part, and a sub-hole has a cross-sectional shape that can accommodate the roof part, and the tip of the sub-hole is closed by an inner end wall, and the imaging element The image forming element is fixed to the holder by bringing the tip end surface of the roof portion into contact with the inner end wall.

[For production]

In the above configuration, each imaging element includes an object-side lens section, an image-side lens section, a first optical path section, a second optical path section, and a roof section in an integrated structure, and forms a royal life-size image. I'm starting to get it. This integrated imaging element has less variation between thick and thin parts than one in which parts are connected in an array, so warping is less likely to occur. Each imaging element is inserted into each opening of the holder, and its position is determined in the vertical and horizontal directions within the main hole, which has a cross-sectional shape that matches the contours of at least the object side lens part and the image side lens part, and the tip of the roof part. Since the imaging element is fixed to the holder by bringing the surface into contact with the inner end wall of the sub-hole, the imaging element can be easily positioned and assembled. Further, since the opening into which each imaging element is inserted is separated from the adjacent opening by a partition wall, there is no generation of stray light or flare light.

〔Example〕

Referring to FIGS. 1 to 3, an imaging device 10 according to a first embodiment of the present invention includes a plurality of imaging elements 12 and a holder 14 that accommodates the plurality of imaging elements 12. . Each imaging element 12 is integrally molded from a transparent resin material and has the following structure. That is, each imaging element 12 is molded from transparent resin and includes an object-side lens section 16 and an image-side lens section 18 that face each other with an interval on a predetermined axis. The object side lens section 16 is directed toward the object to be read, and the image side lens section 18 is directed toward the image forming section, and the object side lens section 16 and the image side lens section 18 are formed symmetrically with respect to each other. Therefore, it can also be used in reverse. The object side lens section 16 and the image side lens section 18 are convex lenses, and when the object to be read is positioned at the focal point, the light passing through the lenses becomes parallel rays.

The first optical path section 20 and the second optical path section 22 are the object side lens section 1
The first optical path section 20 and the second optical path section 22 have a first reflecting surface 24 and a second reflecting surface 26 that are V-shaped. Further, the roof section 28 is connected to the first optical path section 20 and the second optical path section 22.
It is formed on the opposite side of the first reflective surface 24 and the second reflective surface 26 along. The roof portion 28 includes a downward roof-like prism, and this prism has reflective surfaces 32 and 34 on both sides of a peak 30 at the lower center end.

Both end surfaces 36 and 38 of the roof section 28 are flat surfaces perpendicular to the axis thereof, and the length between the both end surfaces 36 and 38 of the roof section 28 is longer than the total length of the first optical path section 20 and the second optical path section 22. It's shorter.

The optical path of light in such an imaging element 12 is as shown by arrows in FIGS. 2 and 3. For example, light that enters the object-side lens section 16 through its optical axis is reflected toward the roof section 28 at the first reflecting surface 24, and further reflected light from the roof section 28 is reflected at the second reflecting surface 26. The light then moves toward the image side lens section 18. If the object S to be read stands on the optical axis as shown by the solid line, then the image I also stands in the same orientation as shown by the broken line. Furthermore, the light incident from the left and right directions of the optical axis is reflected twice by the opposite surfaces 32 and 34 of the roof portion 28, as shown in FIG.
The left and right direction of is reversed. In this way, a royal life-size image is obtained.

The holder 14 has a plurality of openings 42 separated by a partition wall 40 for individually inserting a plurality of imaging elements 12 . Although holder 14 is shown in FIG. 1 as housing five imaging elements 12, more imaging elements 1 may be used.
Of course, it is possible to accommodate 2. In the embodiment, the partition wall 40 is molded at the same time as the holder 14 is molded;
It is also possible to leave the part open and press-fit a black plate member corresponding to the partition wall 40 after molding.

Each opening 42 has a cross-sectional shape adapted to the shape of the imaging element 12 for longitudinal insertion of each imaging element 12, and consists of two generally rectangular holes 42a, 42b. That is,
Each opening 42 has an object side lens section 16 and an image side lens section 1.
The main hole 42a has a cross-sectional shape that conforms to the contour of the roof portion 28, and the sub-hole portion 42b has a cross-sectional shape that conforms to the contour of the roof portion 28. In the embodiment, since the object side lens section 16 and the image side lens section 18 are approximately rectangular, the main hole section 42
The cross-sectional shape of a is also rectangular. If the object side lens part 16 and the image side lens part 1B are circular,
The cross-sectional shape of the main hole 42a is also circular. First optical path section 2
0 and the second optical path section 22 are continuous at their respective roots with the same cross-sectional shape as the object side lens section 16 and the image side lens section 1B, and the first reflecting surface 2 on the upper surface side extends from the root to the center.
4 and the second reflecting surface 26 are narrow, but the lower surface side has a constant planar shape. Therefore, if the object side lens section 16 and the image side lens section 18 can be inserted into the main hole 42a, the first optical path section 20 and the second optical path section 22 can also be inserted into the main hole 42a,
In addition, the object side lens section 16 and the image side lens section 18 are held in predetermined postures within the main hole 42a.

As shown in FIG. 3, the sub-hole 42b is the main hole 42a.
These main holes 42 have a rectangular cross-sectional shape smaller than
A step 42C is formed between a and the sub-hole 42b. Therefore, when inserting each imaging element 12 into each opening 42,
Both edges of the first optical path section 20 and the second optical path section 22 are stepped 42c.
The roof part 28 is supported by the roof part 28 so that the peak 30 at the lower center end thereof floats above the bottom wall of the sub-hole part 42b.

Furthermore, the main hole 42a is formed to penetrate between the front and back surfaces of the holder 14, but the sub-hole 42b is open only on the front side of the holder 14, and the tip side in the insertion direction is closed by the inner end wall 44. has been done. When each imaging element 12 is inserted into each opening 42 , the front end surface 36 of the roof portion 28 of each imaging element 12 in the insertion direction comes into contact with this inner end wall 44 . In this way, the tip end surface 36 of the roof portion 28 is connected to the inner end wall 44 of the sub-hole portion 42b.
By bringing the holder 1 of each imaging element 12 into contact with the
4 can be positioned.

In the embodiment shown in FIGS. 1 and 2, the secondary hole 42
A part of the region including b is a groove 46 depressed from the surface of the holder 14. In addition, deeper small grooves 48 are formed at both ends of this groove 46. An elastic plate 5 is provided in the groove 46.
0 and a holding plate 52 can be fitted into each other, and the claws 54 at both ends of the holding plate 52 are frictionally fitted into the small grooves 48. Therefore, the tip end surface 36 of the roof section 28 is brought into contact with the inner end wall 44 of the sub-hole section 42b, and the rear end surface 38 of the roof section 28 is held down by the pressing plate 52 via the elastic plate 50, whereby each imaging element 12 is fixed to the holder 14. As a result, the object-side lens section 16 and the image-side lens section 18 come to fit within the main hole 42a, as shown in FIG. In addition, the holding plate 52
The pawls 54 at both ends of the hole 48 may not only be a friction fit in the small hole 48, but may also be a snap fit.

Further, as shown in FIG. 4, the object side lens section 16 and the image side lens section 18 are accommodated within the main hole 42a, and the object side lens section 16 and the image side lens section 18 are accommodated within the main hole 42a. A transparent protective cover 56 may be attached to the outside.

Further, instead of fixing each imaging element 12 to the holder 14 by pressing the rear end surface 38 of the roof portion 28 with the pressing plate 52 via the elastic plate 50, other fixing means may be employed. For example, as shown in FIG.
4, and these abutting surfaces can also be fixed to each other with an adhesive 58.

Furthermore, as shown in FIG.
Reflective surface 24, second reflective surface 26, reflective surface 32 of roof portion 28
, 34 is preferably provided with a reflective film to increase reflection efficiency. In FIG. 6, reflective films 60 made of aluminum or silver are provided on the first reflective surface 24 and the second reflective surface 26, respectively.
A protective film 62 of 5 in 2 is further provided thereon. A similar reflective film 60 and protective film 62 are also provided on the reflective surfaces 32 and 34 of the roof portion 28.

FIGS. 7 and 8 are diagrams showing still other embodiments of the present invention. Although this embodiment is shown upside down from the embodiment of FIG. 1, the components are quite similar. for example,
The imaging element 12 includes an object side lens section 16 and an image side lens section 1.
8. A first optical path section 20 having a first reflective surface 24, a second optical path section 22 having a second reflective surface 26, and reflective surfaces 32, 3
4 and both end surfaces 3 of the roof portion 28.
The length between 6 and 38 is the length between the first optical path section 20 and the second optical path section 2.
It is shorter than the total length of 2.

In FIGS. 7 and 8, the holder for accommodating the imaging element 12 includes a holder main body 14a and a holder cover 14b.
After the imaging element 12 is inserted into the holder body 14a, the holder cover 14b is fixed to the holder body 14a. Furthermore, an elastic plate 50 and a pressing plate 5
2 can be fitted. A partition wall 40 is provided in the holder main body 14a, and the opening 42 is partitioned off by the partition wall 40. Similarly, the opening 42 includes a main hole 42a having a cross-sectional shape that matches the contours of the object-side lens section 16 and the image-side lens section 18, and a sub-hole 4 that can accommodate the roof section 28.
2b. By bringing the tip end surface 36 of the roof portion 28 into contact with the inner end wall 44 of the sub-hole portion 42b,
Each imaging element 12 can be positioned with respect to the holders 14a, 14b.

〔Effect of the invention〕

As explained above, in the imaging device according to the present invention, an imaging element in which various optical components having a lens portion and a reflective surface are integrally formed is adapted to a holder, and in this case, the holder The main hole has a plurality of openings partitioned by partition walls for individually inserting the image elements, and each opening has a cross-sectional shape that matches the contours of the object-side lens part and the image-side lens part. , a sub-hole having a cross-sectional shape capable of accommodating the roof part, a tip end of the sub-hole being closed by an inner end wall, and a front end surface of the roof part of the imaging element facing the inner end wall. Since the imaging elements are fixed to the holder by making contact with each other, the imaging elements are less likely to warp, and each imaging element can be easily positioned and assembled in the holder. Since each imaging element is separated by a partition wall within the holder, it is possible to eliminate the generation of stray light and flare light.

[Brief explanation of drawings]

FIG. 1 is an exploded perspective view showing a first embodiment of the imaging device of the present invention, FIG. 2 is a cross-sectional view of the imaging device shown in FIG. 1 in an assembled state, and FIG. 3 is a line drawn along the line 4 is a sectional view showing the second embodiment of the present invention, FIG. 5 is a sectional view showing the third embodiment of the present invention, and FIG. 6 is a sectional view taken along the reflecting surface. FIG. 7 is an exploded perspective view showing a fourth embodiment of the present invention, and FIG. 8 is a sectional view of the imaging device shown in FIG. 7 in an assembled state. DESCRIPTION OF SYMBOLS 12... Imaging element, 16... Object side lens part, 20, 22... Optical path part, 28... Roof part, 40... Partition wall, 42a... Main hole part, 44. ...Inner end wall. DESCRIPTION OF SYMBOLS 14... Holder, 18... Image side lens part, 24, 26... Reflective surface, 36... Tip surface, 42... Opening part, 42b... Sub-hole part,

Claims (1)

[Claims] A first reflective surface ( 24) and a second reflective surface (26), a first optical path section (20) and a second optical path section (22), and a roof section (28) formed along the first optical path section and the second optical path section. ), the incident light from the object-side lens portion (16) is reflected toward the roof portion (28) at the first reflecting surface (24), and the reflected light from the roof portion (28) is further reflected from the roof portion (28). an integrally structured imaging element (12) configured to reflect light toward the image-side lens part (18) at the second reflecting surface (26); and a holder that accommodates a plurality of the imaging elements (12). (14), wherein the holder (14) has a plurality of openings (42) partitioned by partition walls (40) for individually inserting the imaging elements (12). and each opening (42) is connected to the object side lens section (16) and the image side lens section (18).
a main hole (42a) with a cross-sectional shape that matches the contour of the roof, and a sub-hole (42b) with a cross-sectional shape that can accommodate the roof part (28).
), the tip of the sub-hole (42b) is closed by the inner end wall (44), and the tip surface (36) of the roof portion (28) of the imaging element (12) is closed by the inner end. Wall (44
) to bring the imaging element (12) into contact with the holder (1).
4) An imaging device fixed to.