JP2001116905A - Lens array optical device and manufacturing method of comb-tooth-shaped structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively remove the crosstalk of an image without increasing the number of components. SOLUTION: A linear image sensor unit comprises a lens array 7 which converges reflected light from a document 10, the comb-tooth-shaped structure 6 which is arranged on the light projection side of the lens array 7, a sensor array 13 which detects and converts a document image formed by the lens array 7 into an electric signal; and the comb-tooth-shaped structure 6 is arranged between a rear lens array 12 and the sensor array 13 and the rear lens array 12 and an unevenness groove 1 are matched to prevent light from traveling around from an imaging gap where projection parts 4 are adjacent, thereby crosstalk is effectively removed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is applicable to a scanner, a facsimile, and the like, and is a lens array optical apparatus for dividing a document image into a plurality of areas by using a lens array and individually forming an image, and crosstalk between lenses. The present invention relates to a method for producing a comb-shaped structure for preventing the occurrence of a comb-like structure.

[0002]

2. Description of the Related Art As an optical system of an original reading apparatus such as a scanner or a facsimile, a) a combination of a single imaging lens and a sensor array, b) a lens array and a sensor array in which a plurality of lenses are arranged in a line. Are known. In the latter method, a plurality of lenses individually form a plurality of images, share a region to be formed, and combine these images to obtain an entire image. Therefore, as compared with the former method, there is an advantage that the size of the entire optical system can be reduced and the angle of view of the lens can be reduced, so that the design of the lens is facilitated.

In the method using a lens array, the area where each lens forms an image is shared, and if the same area is formed by another lens different from the responsible lens, a crosstalk phenomenon in which the image forming areas overlap is performed. Occurs. When the crosstalk occurs, the contrast of the image is reduced or a ghost image is generated, thereby deteriorating the image quality.

As a method of removing such crosstalk, a method of arranging a cylindrical diaphragm for each lens, a method of arranging a plate-like diaphragm having a large number of through holes formed in a relatively thick plate, and a method of arranging an aperture in the middle of a lens. Is conceivable.

[0005]

In a general scanner or facsimile, the original reading width is set to A4 size or B4 size, and it is necessary to arrange several hundred lenses having a diameter of 0.1 mm to several mm corresponding to this width. There is.

[0006] If a large number of lenses are provided with individual cylindrical apertures, the cost of parts and assembly is increased, and the size of the cylindrical aperture is inevitably reduced due to the small size of the lenses. And handling becomes difficult.

On the other hand, in the case of a plate-shaped aperture, there is no need for a low-cost processing method because it is necessary to form many holes longer than the diameter of the through-hole.

In the method of arranging the aperture, the lens portion is manufactured separately in front and rear, and the aperture is mounted therein, so that the total number of parts increases and the cost increases.

As a related prior art, Japanese Patent Application Laid-Open No. 61-22 / 1986
No. 6,701, and describes a configuration in which a projecting partition plate is formed on the wall surface of a lens array. However, the rigidity of the partition plate is low, and the partition plate easily falls down, and it is difficult to realize the material processing method.

Another prior art is disclosed in Japanese Patent Laid-Open No. 3-15760.
No. 2 describes a method of forming a cylindrical through-hole by joining two substrates having grooves formed face to face. However, it is difficult to accurately join two long members each having a length of about 200 mm.

An object of the present invention is to provide a lens array optical device and a method for manufacturing a comb-like structure capable of effectively eliminating image crosstalk without increasing the number of parts.

[0012]

According to the present invention, a plurality of lenses are arranged in a line, and separate an original image into a plurality of areas and individually form an image. And a comb-shaped structure in which concave / convex grooves separated by are formed substantially parallel to the optical axis of the lens.

According to the present invention, a comb-shaped structure having concave and convex grooves having changed optical properties is arranged on the light incident side or the light output side of the lens, and the lens array is aligned with the concave and convex grooves so as to be adjacent to each other. Since it is possible to prevent the light from escaping from the imaging space, crosstalk can be effectively removed.

Also, while it is difficult to form a large number of thin and long through holes with the conventional plate-shaped diaphragm, the comb-tooth-like structure according to the present invention has an uneven groove. And can be realized at extremely low cost.

Further, the present invention is characterized in that the comb-shaped structure is formed by forming an uneven groove at an end of an opaque substrate.

According to the present invention, since the concave and convex grooves at the end of the substrate have a structure suitable for a molding method such as resin injection molding or metal die casting, they can be mass-processed with high accuracy and at low cost. Further, since the opaque substrate is light absorbing, noise light can be reliably cut.

Further, the present invention is characterized in that the comb-shaped structure is formed by forming a concave and convex groove at an end of a transparent substrate and forming a light absorbing film on the surface of the concave and convex groove. I do.

According to the present invention, the concave / convex grooves at the end of the substrate have a structure suitable for a molding method such as resin injection molding or metal die casting, and can be mass-processed with high accuracy and at low cost. Further, by forming a light absorbing film on the surface of the uneven groove, noise light can be reliably cut.

Further, the present invention is characterized in that the pitch of the concave and convex grooves of the comb-shaped structure is equal to the lens arrangement pitch, the lens optical axis passes through the convex portion, and the concave portion is located between adjacent lenses. I do.

According to the present invention, since the lens optical axis passes through the convex portion of the concave / convex groove and the concave portion is formed so as to divide the lens optical axis, light from the adjacent image forming space is prevented from wrapping around the convex / concave groove. It can be reliably prevented by the light absorbing film on the surface. Also,
Compared with a conventional structure having a protruding partition plate, the rigidity is remarkably increased, and the production becomes easy.

Also, in the present invention, the pitch of the concave and convex grooves of the comb-shaped structure is equal to twice the lens arrangement pitch, the concave portion is filled with a transparent material, and the convex and concave portions are adjacent to the optical axis of the lens. Are respectively passed.

According to the present invention, the projections and the depressions are formed of a transparent material, and the light absorbing film is interposed between the projections and the depressions. Therefore, it is possible to surely prevent the light from entering from the adjacent imaging space. In addition, since the optical path lengths of the convex portion and the concave portion match, optical characteristics can be made uniform. In addition, the rigidity is significantly higher than that of a conventional structure having a protruding partition plate, which facilitates manufacturing.

Further, the present invention is characterized in that a plurality of lenses and a comb-like structure are integrally formed.

According to the present invention, the number of parts can be reduced and the assembling process can be simplified by integrally forming the plurality of lenses and the comb-like structure. Such integral formation of the lens and the comb-like structure can be easily realized by a molding method such as resin molding.

Further, the present invention is characterized in that the convex portion is covered with the same material as the transparent material filled in the concave portion.

According to the present invention, by covering the convex portion with the same material as the transparent material of the concave portion, burrs are less likely to occur at the time of molding, and even if burrs occur, they become far from the lens optical axis. The effect on the optical system is reduced.
An ultraviolet curable resin or the like can be used as such a transparent material.

Further, the present invention is characterized in that the transparent material and the convex portions filled in the concave portions are fixed by a reinforcing substrate.

According to the present invention, when a curable resin such as an ultraviolet curable resin is used as a filling material for the concave portion, if a tensile stress remains during curing shrinkage, the comb-shaped structure may be warped. By fixing the reinforcing substrate, warpage deformation can be prevented.

According to the present invention, there is further provided a step of forming a transparent substrate having an uneven groove on the surface, a step of forming a light absorbing film on the surface of the uneven groove, and a step of cutting the substrate along a direction perpendicular to the uneven groove. And producing a comb-shaped structure.

According to the present invention, a large number of comb-tooth-like structures having the same cross-sectional shape can be produced, and the cost can be reduced.

Further, the present invention is characterized in that it includes a step of integrally forming a plurality of lenses on a cut surface of the substrate.

According to the present invention, the number of parts can be reduced and the assembling process can be simplified by integrally forming the plurality of lenses and the comb-like structure.

[0033]

1 to 4 show a first embodiment of the present invention. FIG. 1 (a) is a plan view of a comb-like structure, and FIG.
2B is a front view of the comb-shaped structure, FIG. 2 is a perspective view of a lens array optical system, FIG. 3 is a configuration diagram of a one-dimensional image sensor unit, and FIG.

As shown in FIG. 1, the comb-shaped structure 6 has the concave and convex grooves 1 including the convex portions 4 and the concave portions 3 formed at a constant pitch along the longitudinal end face 2 of the elongated substrate. The concave portion 3 has an arc-shaped contour, and secures an imaging space of the lens. In addition,
The contour shape of the concave portion 3 may be square, and can be changed as appropriate according to the manufacturing method. The convex portions 4 protrude between the adjacent concave portions 3 and partition the imaging space of the adjacent lenses. The end of the convex portion 4 is preferably square, but may be slightly rounded at the corner from the viewpoint of preventing crosstalk, provided that the radius of curvature R is about ３ of the thickness of the convex portion 4. no problem.

As shown in FIG. 2, the comb-shaped structure 6 is arranged on a light incident side or a light emitting side of a lens array 7 in which a plurality of microlenses 5 are arranged in a line shape. Is set substantially parallel to the optical axis of the lens, and the optical axis of each microlens 5 passes near the center of the recess 3.

The pitch of the concave and convex grooves 1 is equal to the arrangement pitch of the microlenses 5, and the gap size of the concave portion 3 is substantially equal to the diameter of the microlens 5. As the gap between the recesses 3 is larger, the lens imaging space is wider, so that the light use efficiency is higher. However, when the thickness of the protrusions 4 is smaller, manufacturing becomes difficult in terms of strength reduction. Practically, the thickness of the projection 4 is preferably about 1/4 to 1/5 of the diameter of the microlens 5, and the gap between the depressions 3 is preferably about 3/4 to 4/5 of the diameter of the microlens 5. .

The gap and length of the recess 3 (thickness of the comb-shaped structure 6) correspond to the diameter and length of the cylindrical diaphragm, and the aspect ratio, which is the ratio of gap to length, is 4 to 4. It is preferable to set it to about 5 from the viewpoint of ease of manufacturing and prevention of crosstalk.

With respect to the method of manufacturing the comb-shaped structure 6, a method of cutting a substrate made of metal, synthetic resin, or the like with a blade, grinding with a grindstone, or laser processing with laser light is considered. It can be appropriately selected from the viewpoint of manufacturing cost.
Practically, a resin molding method of injecting a resin into a mold corresponding to the concave and convex grooves 1 of the comb-shaped structure 6 and molding the resin is preferable. Examples of the resin molding method include injection molding and injection compression molding. As the resin material, those having high precision of the molded article and little warping or distortion after molding are preferable, and for example, acrylic resin, polycarbonate resin, liquid crystal polymer resin (LCP), polyphenylsulfone resin (PPS) and the like are preferable. When the comb-shaped structure 6 is molded, it is preferable that the shape change is not abrupt, and the contour of the concave portion 3 is preferably an arc.

The optical characteristics of the comb-shaped structure 6 may be any as long as the imaging space of the adjacent lens can be divided by a change in optical properties, and a light-absorbing material is preferable, and furthermore, surface scattering of light is prevented. It is preferable that the surface is rough in order to perform the treatment.

As shown in FIG. 3, the one-dimensional image sensor unit includes a lens array 7 for condensing the reflected light from the original 10 and a comb-shaped structure 6 arranged on the light emitting side of the lens array 7. A sensor array 13 for detecting an original image formed by the lens array 7 and converting the image into an electric signal;
It is composed of a housing (not shown) for holding them.

The lens array 7 includes a front lens array 11
The rear lens array 12 is arranged at a fixed distance, and separates the image of the document 10 into a plurality of regions to form individual images. The lens array 7 includes a front lens array 11
An optical system that forms an intermediate image of the document 10 between the lens array and the rear lens array 12 is employed, so that the numerical aperture is reduced and crosstalk can be prevented. It can handle changes.

The comb-shaped structure 6 includes a rear lens array 12
And the sensor array 13, the rear lens array 12 and the concave / convex groove 1 are aligned,
Since the convex portion 4 functions as a light shielding member for preventing light from entering from the adjacent imaging space, crosstalk can be effectively removed.

The sensor array 13 includes a linear CCD sensor having a plurality of light receiving pixels and the like.
Detects the divided image of the original and converts it to an electrical signal.
It is output as a reading signal of a document image.

Next, the function of the comb-shaped structure 6 will be described. Referring to FIG. 4, the lens Pn of the front lens array 11 forms an intermediate image Ic by forming an image Ia of the original 10, and the rear lens array 1 which is coaxial with the lens Pn.
The second lens Qn forms the final image Ib on the sensor array 13. At this time, the light Rn traveling at a large angle with respect to the intermediate image Ic enters the adjacent lens Qn-1 and becomes noise light. As a countermeasure, by disposing the comb-shaped structure 6 on the light emission side of the rear lens array 12, the projections 4 block the light Rn, so that the incidence on the sensor array 13 can be prevented.

FIG. 5 is a perspective view showing a second embodiment of the present invention. In the comb-tooth-like structure 17, concave and convex grooves including the convex portions 14 and the concave portions 15 are formed at a constant pitch along the longitudinal end surface of the elongated substrate. The substrate is formed of a transparent material, a light absorbing film 18 is formed on the surface of the concave and convex grooves, and the transparent material is filled on the film 18 of the concave portion 15.

The comb-shaped structure 17 is disposed on the light incident side or the light emitting side of a lens array in which a plurality of microlenses 16 are arranged in a line, and the generatrix of the concave and convex grooves is substantially parallel to the optical axis of the lens. The optical axis of each micro lens 16 is set near the center of the convex portion 14 and the concave portion 15 respectively.

The pitch of the concavo-convex grooves is equal to twice the arrangement pitch of the microlenses 16, and the widths of the convex portions 14 and the concave portions 15 are almost the same in order to ensure an even imaging space for each microlens 16.

The width and length of the convex portion 14 and the concave portion 15 (thickness of the comb-like structure 17) correspond to the diameter and length of the cylindrical diaphragm. It is preferable to set it to about 4 to 5 in terms of ease of manufacturing and prevention of crosstalk.

Regarding the method of manufacturing the comb-shaped structure 17, a method of cutting a transparent substrate made of a synthetic resin or the like with a blade, grinding with a grindstone, or laser processing with a laser beam is considered. It can be appropriately selected from the viewpoint of cost.
As the transparent resin material, a material having high precision of a molded product and little warpage or distortion after molding is preferable, and for example, an acrylic resin, a polycarbonate resin, a styrene resin, a polyolefin resin and the like are preferable.

As a method of manufacturing the light absorbing film 18, for example, there is a method of spray-coating a black paint in which a pigment such as carbon black is dispersed in a resin material.

As a transparent material to be filled in the concave portion 15, for example, an ultraviolet curable resin can be used. After the light-absorbing film 18 is formed on the surface of the concave and convex grooves, a liquid ultraviolet curable resin is dropped and filled in the concave portion 15, and then the resin is cured by irradiation with ultraviolet light. The transparent material of the convex portion 14 and the transparent material of the concave portion 15 are formed such that the optical characteristics become uniform.
The same material or a material having the same refractive index is preferable, whereby the optical path lengths of the convex portion and the concave portion match, and the optical characteristics of the adjacent lens imaging space can be made uniform.

After the ultraviolet curable resin is dropped into the concave portion 15,
By scraping off excess resin on the surface with a blade or the like, it is possible to suppress the influence of residual tensile stress generated during resin curing.

Further, with respect to the mass production method of the comb-shaped structure 17, a method such as a so-called Kintaro candy can be considered. That is, after forming a transparent substrate having an uneven groove on the surface by a resin molding method or the like, a light-absorbing film 18 is formed on the surface of the uneven groove by painting a black paint or the like, and then the concave portion is filled with an ultraviolet curable resin. After hardening, the substrate is cut at a constant pitch along the direction perpendicular to the concave and convex grooves by mechanical processing, laser processing, or the like. By such a manufacturing method, a large number of comb-tooth-like structures 17 having the same cross-sectional shape can be produced, and the cost can be reduced.

Such a comb-like structure 17 can be used as an alternative to the comb-like structure 6 of FIG. 3, and the one-dimensional image sensor unit condenses the reflected light from the original 10 similarly to the structure of FIG. A lens array 7, a comb-like structure 17 disposed on the light emission side of the lens array 7,
The sensor array 13 detects an original image formed by the sensor array and converts it into an electric signal, and a housing (not shown) for holding the sensor array.

The comb-shaped structure 17 is provided on the rear lens array 1.
The light-absorbing film 18 prevents light from escaping from the adjacent imaging space by aligning the rear lens array 12 with the projections 14 and the depressions 15 at an intermediate position between the lens array 2 and the sensor array 13. Since it functions as a light shielding member, crosstalk can be effectively removed.

FIG. 6 is a perspective view showing a third embodiment of the present invention. In the comb-shaped structure 29, concave and convex grooves including a convex portion 27 and a concave portion 28 are formed at a constant pitch along the longitudinal end surface of the elongated substrate. The substrate is formed of a transparent material, and a light-absorbing film 30 is formed on the surface of the uneven groove.

As shown in FIG. 5, the comb-shaped structure 29 is arranged on the light incident side or the light emitting side of a lens array in which a plurality of microlenses are arranged in a line. The microlenses are set substantially parallel to the axes, and the optical axes of the microlenses pass through the vicinity of the center of the convex portion 27, respectively.

The pitch of the concave and convex grooves is equal to the arrangement pitch of the microlenses, and the width of the convex portion 27 is long and the concave portion 28 is narrow and wedge-shaped in order to secure a wide imaging space for the microlenses.

The width and length of the convex portion 27 (thickness of the comb-like structure 29) correspond to the diameter and length of the cylindrical diaphragm, and the aspect ratio, which is the ratio of width to length, is 4 to 5. It is preferable to set it to such a degree in terms of ease of manufacturing and prevention of crosstalk.

Regarding the method of manufacturing the comb-shaped structure 29, a method of cutting a transparent substrate made of a synthetic resin or the like with a blade, grinding with a grindstone, or laser processing with a laser beam is considered. It can be appropriately selected from the viewpoint of cost.
As the transparent resin material, a material having high precision of a molded product and little warpage or distortion after molding is preferable, and for example, an acrylic resin, a polycarbonate resin, a styrene resin, a polyolefin resin and the like are preferable.

As a method of manufacturing the light absorbing film 30, for example, there is a method of spray coating a black paint in which a pigment such as carbon black is dispersed in a resin material.

Such a comb-like structure 29 can be used as an alternative to the comb-like structure 6 of FIG. 3, and the one-dimensional image sensor unit condenses the reflected light from the original 10 similarly to the structure of FIG. A lens array 7, a comb-shaped structure 29 arranged on the light emission side of the lens array 7, and a lens array 7
The sensor array 13 detects an original image formed by the sensor array and converts it into an electric signal, and a housing (not shown) for holding the sensor array.

The comb-like structure 29 is provided on the rear lens array 1
2 and the sensor array 13, and by aligning the rear lens array 12 with the concave and convex grooves,
Since the light-absorbing film 30 functions as a light shielding member for preventing light from entering from the adjacent imaging space, crosstalk can be effectively removed.

FIG. 7 is a perspective view showing a fourth embodiment of the present invention. The overall shape and function of the comb-shaped structure 29 are the same as those in FIG. 6, but differ in that the microlenses 31 are integrally formed near the center of the end face of each projection 27. The micro lens 31 can be formed on one end surface or both end surfaces of the convex portion 27.

The plurality of microlenses 31 and the comb-like structure 29 can be integrally formed by using a molding method such as resin molding, so that the number of parts can be reduced, the assembly process can be simplified,
Cost can be reduced.

FIG. 8 is a perspective view showing a fifth embodiment of the present invention. The overall shape and function of the comb-like structure 19 are the same as those in FIG. 5 except that the microlenses 23 are integrally formed near the centers of both end surfaces of the convex portion 22 and the concave portion 21, respectively. I do.

In the comb-like structure 19, concave and convex grooves formed of convex portions 22 and concave portions 21 are formed at a constant pitch along the longitudinal end face of the elongated substrate. The substrate is formed of a transparent material, a light absorbing film 20 is formed on the surface of the concave and convex grooves,
Is filled with a transparent material. In order to uniformly secure the imaging space of each microlens 23,
And the width of the concave portion 21 is substantially the same. The generatrix direction of the concave and convex grooves is set substantially parallel to the optical axis of the lens, and the optical axis of each microlens 23 passes near the center of the convex portion 22 and the concave portion 21 respectively.

Regarding the method of manufacturing the comb-shaped structure 19, a method of cutting a transparent substrate made of a synthetic resin or the like with a cutting tool, grinding with a grindstone, or laser processing with laser light is considered. It can be appropriately selected from the viewpoint of cost.
As the transparent resin material, a material having high precision of a molded product and little warpage or distortion after molding is preferable, and for example, an acrylic resin, a polycarbonate resin, a styrene resin, a polyolefin resin and the like are preferable.

As a method for producing the light absorbing film 20, for example, there is a method of spray coating a black paint in which a pigment such as carbon black is dispersed in a resin material.

As the transparent material to be filled in the recess 21, for example, an ultraviolet curable resin can be used. After the light-absorbing film 20 is formed on the surface of the concave and convex grooves, a liquid ultraviolet curable resin is dropped and filled in the concave portion 21, and then the resin is cured by irradiation with ultraviolet light. The transparent material of the convex portion 22 and the transparent material of the concave portion 21 are formed such that optical characteristics are uniform.
The same material or a material having the same refractive index is preferable, whereby the optical path lengths of the convex portion and the concave portion match, and the optical characteristics of the adjacent lens imaging space can be made uniform.

Regarding the method of mass-producing the comb-shaped structure 19, a method such as a so-called Kintaro candy can be considered. That is, after forming a transparent substrate having an uneven groove on the surface by a resin molding method or the like, a light-absorbing film 20 is formed on the surface of the uneven groove by applying a black paint or the like, and then the concave portion is filled with an ultraviolet curable resin. After hardening, the substrate is cut at a constant pitch along the direction perpendicular to the concave and convex grooves by mechanical processing, laser processing, or the like. Next, the microlenses 23 are integrally formed near the centers of the convex portions 22 and the concave portions 21 on the cut surface of the substrate. Comb-like structure 1 having the same cross-sectional shape by such a manufacturing method
9 can be produced in large quantities, and the cost can be reduced.

Regarding the method of integrally forming the microlenses 23, a method using an ultraviolet curing resin and a mold is possible. For example, after an appropriate amount of an ultraviolet curable resin is dropped on a mold on which an array of microlenses 23 is formed or on the substrate side, the mold is pressed against the substrate to transfer the mold shape, and the resin is cured by ultraviolet irradiation.

The plurality of microlenses 23 and the comb-like structures 19 can be integrally formed by using a molding method such as resin molding, so that the number of parts can be reduced, and the assembling process can be simplified.
Cost can be reduced.

FIG. 9 is a perspective view showing a sixth embodiment of the present invention, and FIG. 10 is a front view thereof. The overall shape and function of the comb-like structure 19 are the same as those in FIG. 8, but differ in that the additional layer 25 is formed on the concave and convex grooves.

The additional layer 25 is made of the same material as the transparent material filled in the concave portion, for example, an ultraviolet curable resin. As a manufacturing method of the additional layer 25, 1) a batch curing method in which an ultraviolet curable resin is dripped excessively when filling the concave portion to cover both the concave portion and the convex portion, and then the resin is cured by irradiation with ultraviolet light; A two-step curing method is possible, in which the cured resin is filled only in the concave portions, the resin is cured by ultraviolet irradiation, and then the ultraviolet curable resin is dropped on both the concave portions and the convex portions, and then the resin is cured by ultraviolet irradiation. It is.
Thereafter, as described above, the substrate is cut at a constant pitch along the direction perpendicular to the concave and convex grooves by mechanical processing or laser processing, and then the microlens 23 is placed near the center of the convex and concave portions on the cut surface of the substrate. It is formed integrally by die pressing.

At this time, if the additional layer 25 does not exist, the ultraviolet curable resin which becomes the microlenses 23 in the press-contact of the mold leaches between the mold and the substrate. It will appear as. When burrs come out, they cause dust and defects when released from the mold, which adversely affects the product defect rate and yield.

On the other hand, when the thick additional layer 25 is formed,
Even if the ultraviolet curable resin that becomes the microlenses 23 oozes between the mold and the substrate during the mold pressing, the resin hardly protrudes from the substrate, and the occurrence of burrs can be prevented, so that the yield can be improved.

FIG. 11 is a perspective view showing a seventh embodiment of the present invention. The overall shape and function of the comb-like structure 19 are the same as those in FIG.
6 is fixed by an adhesive or the like.

The reinforcing substrate 26 has a function similar to that of the additional layer 25 shown in FIG.
Even if the ultraviolet curable resin that becomes the microlenses 23 oozes between the mold and the substrate during the mold pressing, the resin hardly protrudes from the substrate, and the occurrence of burrs can be prevented, so that the yield can be improved.

Also, by providing the reinforcing substrate 26 with strength, when a curable resin such as an ultraviolet curable resin is used as a filling material for the concave portions, if a tensile stress remains during curing shrinkage, the warp deformation of the comb-tooth-like structure 19. However, warpage can be prevented by fixing the reinforcing substrate.

As described above, the resin molding method has mainly been described as a method for producing the comb-shaped structure. However, other methods such as die casting of a metal material and bending of a sheet metal can be applied.

[0082]

As described above in detail, according to the present invention, a comb-shaped structure having concave and convex grooves having changed optical properties is arranged on the light incident side or light output side of the lens, and the lens array and the concave and convex grooves are formed. Are matched, it is possible to prevent the sneak of light from the adjacent imaging space, so that the crosstalk can be effectively removed.

Further, while it is difficult to form a large number of thin and long through holes with the conventional plate-shaped diaphragm, the comb-shaped structure according to the present invention has concave and convex grooves. By applying a molding method or the like, manufacturing becomes easy, and cost can be reduced.

[Brief description of the drawings]

1A and 1B show a first embodiment of the present invention, wherein FIG. 1A is a plan view of a comb-like structure, and FIG. 1B is a front view of the comb-like structure.

FIG. 2 is a perspective view of a lens array optical system.

FIG. 3 is a configuration diagram of a one-dimensional image sensor unit.

FIG. 4 is an explanatory diagram of crosstalk prevention.

FIG. 5 is a perspective view showing a second embodiment of the present invention.

FIG. 6 is a perspective view showing a third embodiment of the present invention.

FIG. 7 is a perspective view showing a fourth embodiment of the present invention.

FIG. 8 is a perspective view showing a fifth embodiment of the present invention.

FIG. 9 is a perspective view showing a sixth embodiment of the present invention.

FIG. 10 is a front view showing a sixth embodiment of the present invention.

FIG. 11 is a perspective view showing a seventh embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Concavo-convex groove 2 End surface 3,15,28,21 Concave part 4,14,27,22 Convex part 5,16,23 Micro lens 6,17,19,29 Comb-like structure 7 Lens array 10 Document 11 Front lens array 12 back lens array 13 sensor array 18, 20, 30 film 25 additional layer 26 reinforcing substrate

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H044 AD01 2H108 EA08 EA25 EA56 GA04 GA09 5C051 AA01 BA03 DA03 DB01 DB22 DC02 DC04 DC07 DD04 5C072 AA01 BA02 BA11 DA03 DA15 DA18 DA21 EA05 FA07

Claims (10)

[Claims] 1. A plurality of lenses arranged in a line and dividing a document image into a plurality of regions to individually form images, and concave and convex grooves for dividing an image forming space of an adjacent lens by a change in optical properties. A lens array optical device, comprising: a comb-shaped structure formed substantially parallel to an optical axis. 2. The lens array optical device according to claim 1, wherein the comb-shaped structure is formed by forming an uneven groove at an end of an opaque substrate. 3. The comb-shaped structure is formed by forming an uneven groove at an end of a transparent substrate and forming a light absorbing film on a surface of the uneven groove. 2. The lens array optical device according to 1. 4. The comb-shaped structure according to claim 1, wherein the pitch of the concave and convex grooves is equal to the lens arrangement pitch, the lens optical axis passes through the convex portion, and the concave portion is located between adjacent lenses. 4. The lens array optical device according to 3. 5. The pitch of the concave-convex grooves of the comb-shaped structure is equal to twice the lens arrangement pitch, the concave portion is filled with a transparent material, and the convex portion and the concave portion are respectively passed by the adjacent lens optical axes. The lens array optical device according to claim 3, wherein: 6. The lens array optical device according to claim 3, wherein the plurality of lenses and the comb-shaped structure are formed integrally. 7. The lens array optical device according to claim 6, wherein the convex portion is covered with the same material as the transparent material filled in the concave portion. 8. The lens array optical device according to claim 7, wherein the transparent material filled in the concave portion and the convex portion are fixed by a reinforcing substrate. 9. A step of forming a transparent substrate having an uneven groove on the surface, a step of forming a light-absorbing film on the surface of the uneven groove, and a step of cutting the substrate along a direction perpendicular to the uneven groove. A method for producing a comb-shaped structure, comprising: 10. The method according to claim 9, further comprising the step of integrally forming a plurality of lenses on a cut surface of the substrate.