JP2000227505A - Lens array, lens array assembly equipped with plurality of the same, intermediate product of lens array and production of lens array - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently produce a lens array at a low cost and in an easy production operation by forming plural lenses and a holder part from a light- transmitting resin in a single body and optically separating plural lenses from one another. SOLUTION: The lens array (A) is composed of a resin molded part 5 as the main part obtd. by molding a light-transmitting synthetic resin, and the resin molded part 5 forms the holder part 1 and plural lenses 2. Moreover, the lens array (A) has plural light-shielding parts 3 and a light-shielding film 4 which covers the outer surface of the holder part 1. The resin molded part 5 is an almost rectangular parallelepiped three-dimensional body extended along one direction and having an upper face 5a and a lower face 5b facing each other through a space in the thickness direction. The upper face 5a and the lower 5b are partially formed into convex faces 20a, 20b. The plural light- shielding parts 3 are formed as plural gaps 30 between adjacent lenses 2, and each of plural walls which define the plural gaps 30 is coated with a black coating film 31.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to, for example, forming an image of a document to be read in an image reading apparatus, or forming an image displayed on a display such as a liquid crystal display at a position distant from the display surface. It relates to a lens array used for applications.

[0002]

2. Description of the Related Art As is well known, for example, in a line image sensor type image reading apparatus, a plurality of light receiving elements arranged in a line are used to read an image of a document one line at a time in a main scanning direction. I have. Therefore, it is necessary to use a lens array in which a plurality of lenses are arranged in the main scanning direction as an optical lens for forming an image of a document on the plurality of light receiving elements.

Therefore, conventionally, there is a lens array 9 as shown in FIG. This lens array 9 has a plurality of cylindrical Selfoc lenses 91 held in an elongated block-shaped holder portion 90 extending in a certain direction, and these plural Selfoc lenses 91 are attached to the holder portion 9.
0 are arranged in rows at regular intervals in the longitudinal direction. As shown in FIG. 36, each SELFOC lens 91 can form, for example, objects a and b as erect and equal-magnification images a ′ and b ′.

[0004] Each SELFOC lens 91 is formed such that its refractive index gradually changes as its distance from the center changes so as to meander the incident light inside. For this reason, conventionally, in order to manufacture the lens array 9, first, a plurality of Selfoc lenses 91 are individually manufactured, and then the plurality of Selfoc lenses 91 are placed in the holder unit 90 by using an insert molding method. Buried in the holder 9
0 was resin molded.

Conventionally, as a lens array having a different configuration from the above-described lens array 9, there is a lens array in which a plurality of lenses made of optical fibers cut to a certain size are held in a holder made of synthetic resin. Further, as a lens array capable of forming an inverted image, there is a lens array in which a plurality of glass convex lenses are held by a synthetic resin holder. However, also in the case of manufacturing such a lens array, similarly to the lens array 9 described above, a plurality of lenses manufactured in advance have been incorporated in the holder portion by an insert molding technique.

[0006]

However, in the above-described conventional manufacturing method, the operation of manufacturing the lens and the operation of molding the resin of the holder portion are separately performed, and the number of operation steps for manufacturing the lens array is large. . In addition, the lenses are generally of a small size, and the number of lenses is large, so that handling of a plurality of lenses after their manufacture is very troublesome. In particular, conventionally, when performing a resin molding operation of a holder portion, a plurality of lenses must be accurately positioned and arranged at predetermined positions in a mold, so that the operation has been extremely complicated. . Therefore, conventionally, the productivity of the lens array has been low, and the manufacturing cost has been high.

The present invention has been conceived under such circumstances, and it is an object of the present invention to make it possible to efficiently and inexpensively manufacture a lens array by an easy manufacturing operation.

[0008]

DISCLOSURE OF THE INVENTION In order to solve the above problems, the present invention employs the following technical means.

According to a first aspect of the present invention, there is provided a lens array. This lens array is a lens array having a plurality of lenses and a holder unit connecting the plurality of lenses, wherein the plurality of lenses and the holder unit are made of a synthetic resin having a light transmitting property. It is characterized in that it is integrally formed and has means for optically separating the plurality of lenses.

[0010] The lens array provided by the first aspect of the present invention has a structure in which a plurality of lenses and a holder are molded simultaneously and collectively. Therefore, when compared with a conventional lens in which a plurality of lenses are manufactured separately from the holder and then incorporated into the holder,
The productivity is high, and the manufacturing cost can be significantly reduced. Also, in order to be able to optically separate a plurality of lenses, for example, to prevent or suppress a phenomenon of so-called crosstalk in which light passing through one lens advances into another lens located adjacent thereto. Can also. Therefore, the optical function as the lens array does not become defective due to the translucency of the holder.

In a preferred embodiment of the present invention, a resin molding has an upper surface and a lower surface facing each other at an interval in a thickness direction, and at least one of the upper surface and the lower surface has a convex or concave surface. Portion is formed of the synthetic resin having a light-transmitting property, and, in the resin molded portion, a region where the convex or concave surface is formed is each of the lenses, and the remaining The region is the holder.

According to such a configuration, it is possible to form the entire resin molded portion including the plurality of lenses and the holder portion into a simple shape, and the molding can be further facilitated.

In another preferred embodiment of the present invention,
The means for optically separating the plurality of lenses is a light-absorbing light-shielding portion provided so as to block between the plurality of lenses.

According to such a configuration, for example, light that is going to travel from one lens to another lens adjacent thereto can be appropriately blocked by the light blocking portion, and a plurality of lenses can be optically properly connected to each other. Can be separated. Further, since the light-shielding portion has a light absorbing property, light that has passed through the lens and reached the light-shielding portion is not reflected at a high reflectance toward the original lens, and the characteristics of the lens are further improved. Can be something.

In another preferred embodiment of the present invention,
The light-shielding portion is formed by providing a gap between each of the plurality of lenses and applying a black color or a dark-colored paint near the wall defining the gap.

According to such a configuration, since the gap can be provided by the resin molding process of the lens array, the wall surface defining the gap is subjected to a coating process after the resin molding process of the lens array. The light-shielding portion can be provided by a simple operation. In addition, since the light-shielding portion has a black color or a dark color close thereto, the light absorption rate can be increased.

In another preferred embodiment of the present invention,
The light-shielding portion is formed by providing a gap between each of the plurality of lenses, and inserting a substance or member having a black color or a dark color near the gap in the gap.

According to such a configuration, the gap can be easily provided by the resin molding process of the lens array, and thereafter, only a substance or a member of a predetermined color is simply put into the gap. The light shielding portion can be provided by a simple operation.

In another preferred embodiment of the present invention,
The gap is provided so as not to penetrate the holder.

According to such a configuration, the cross-sectional area of the holder can be prevented from becoming extremely small in the portion where the gap is provided. Therefore, in the resin molding process of the lens array, it is possible to secure the fluidity of the raw material resin supplied into the mold, and it is possible to simplify the molding operation of the holder portion and the plurality of lenses. Also, if the gap is provided so as not to penetrate the holder,
The void will have a bottom. Therefore, by applying, for example, black paint to the bottom wall surface, this portion can be used as a light shielding portion.

In another preferred embodiment of the present invention,
The gap is provided so as to penetrate the holder.

According to such a configuration, the gap can be made large. Therefore, the size of the light-shielding portion formed by using the gap can be increased.

In another preferred embodiment of the present invention,
The gap portion extends linearly in a direction intersecting a direction in which the plurality of lenses are arranged.

According to such a configuration, as compared with the case where the void portion is formed in a curved shape, the production of the resin molding die becomes easier and the cost can be reduced. Further, since the gap extends in a direction intersecting with the direction in which the plurality of lenses are arranged, a plurality of lenses are provided using the gap without forming the gap with a very long dimension. The light-shielding portion enables efficient optical separation.

In another preferred embodiment of the present invention,
The gap portion is provided so as to separate a part of the outer periphery of each lens from the holder portion and form a substantially cylindrical shape.

According to such a configuration, it is possible to provide a configuration in which a light-shielding portion is provided directly on the outer periphery of each lens by, for example, applying black paint to a part of the outer periphery of each lens.

In another preferred embodiment of the present invention,
The gap is provided so that the diameter of each lens becomes smaller as the diameter of the lens becomes one end in the optical axis direction.

According to such a configuration, it becomes easy to manufacture a mold used for resin molding of the lens array. That is, in order to provide a void in the resin molding process of the lens array, it is necessary to provide a convex portion for forming the void in the resin molding die. In this case, in order to make each lens smaller in diameter toward one end in the optical axis direction, the shape of the convex portion is, conversely, a taper in which the thickness gradually increases toward one end in the optical axis direction. Must be Therefore, even when the gap portion needs to be formed with a small opening width, the processing of the convex portion is facilitated by the thickness of the one end side of the convex portion that can be formed. .

In another preferred embodiment of the present invention,
The light-shielding portion is formed of a member of a black color or a dark-colored color close to black embedded in the holder portion.

According to such a configuration, it is possible to easily provide the light shielding portion in the lens array. As a technique for embedding a member of a predetermined color in the holder portion, an insert molding technique can be used. However, unlike the conventional insert molding using a plurality of lenses as insert members, the insert molding in this case can reduce the number of insert members to, for example, one, so that the molding operation is simplified. it can.

In another preferred embodiment of the present invention,
The light-shielding portion is formed by processing a part of the holder portion to a black color or a dark color close thereto.

According to such a configuration, it is not necessary to provide a gap portion for forming a light shielding portion in the lens array, and the resin molding becomes easier as the shape of the lens array can be simplified.

In another preferred embodiment of the present invention,
The entire or substantially entire outer surface of the holder is covered with a light shielding film or a light shielding member.

According to such a configuration, light outside the lens array can be prevented from transmitting through the holder, and the optical function of the lens array can be further enhanced.

In another preferred embodiment of the present invention,
The plurality of lenses are arranged in a line at a predetermined interval, and the holder is formed in a block shape extending in the same direction as the row of the plurality of lenses.

According to such a configuration, it is most suitable for an application in which light traveling from a linear area is received and processed.

In another preferred embodiment of the present invention,
The plurality of lenses are arranged vertically and horizontally at a predetermined interval, and the holder portion has a plate shape extending in the arrangement direction of the plurality of lenses.

According to such a configuration, it is most suitable for an application in which light traveling from a planar area is received and processed.

According to a second aspect of the present invention, there is provided a lens array assembly. This lens array assembly
It has a plurality of lens arrays provided by the first aspect of the present invention, and these plurality of lens arrays
It is characterized in that these lenses are superimposed on each other so as to be aligned on the same optical axis.

In the lens array assembly provided by the second aspect of the present invention, an optical function which is difficult to obtain with only one lens array, for example, a function of forming an erect image of the same magnification is obtained. be able to. As described above, since the manufacturing cost of each of the plurality of lens arrays can be reduced, the cost of the entire lens array assembly can also be reduced. In particular, in the past, in order to form an erect equal-magnification image, it was necessary to use expensive Selfoc lenses or optical fiber lenses,
According to the second aspect of the present invention, such a necessity can be eliminated and the cost can be improved.

In a preferred embodiment of the present invention, the plurality of lens arrays are capable of forming an erect equal-magnification image.

According to such a configuration, it can be suitably used as a substitute for a conventional selfoc lens array or a lens array of optical fibers which has been used to form an erect equal-magnification image.

In another preferred embodiment of the present invention,
The plurality of lens arrays are provided with positioning means that fit or engage with each other so as to position the plurality of lens arrays.

According to such a configuration, each lens of the plurality of lens arrays can be appropriately arranged on the same optical axis.

In another preferred embodiment of the present invention,
All lenses of the plurality of lens arrays are spherical lenses.

According to such a configuration, the entire manufacturing cost can be further reduced because all the lenses are spherical lenses which can be easily formed.

In another preferred embodiment of the present invention,
Of the plurality of lens arrays, each lens of at least one or more lens arrays is an aspheric lens.

According to such a configuration, since the aspherical lens is used, the spherical aberration can be eliminated or reduced, and the image formed can be sharpened.

In another preferred embodiment of the present invention,
The number of the plurality of lens arrays is three or more.

According to such a configuration, the convex or concave curvature of the lens of each lens array can be reduced as much as the number of combined lens arrays is increased. Therefore, the aberration can be reduced by that much, and the formed image can be sharpened.

In another preferred embodiment of the present invention,
At least two or more convex lens arrays are combined with at least one or more concave lens arrays having different Abbe numbers.

According to such a configuration, it is possible to eliminate chromatic aberration, which is suitable for use in forming a color image.

According to a third aspect of the present invention, there is provided an intermediate product of a lens array. In the intermediate product of this lens array, a plurality of lenses and a holder unit connecting the plurality of lenses are integrally formed of a synthetic resin having a light-transmitting property, and a gap is provided between each of the plurality of lenses. Is provided.

The intermediate product of the lens array provided by the third aspect of the present invention can be suitably used for manufacturing the lens array provided by the first aspect of the present invention.

According to a fourth aspect of the present invention, there is provided a method of manufacturing a lens array. In the method of manufacturing the lens array, the plurality of lenses and the holder unit connecting the plurality of lenses are integrally formed of a synthetic resin having a light-transmitting property such that a gap is provided between each of the plurality of lenses. It is characterized by having a first step and a second step of processing at least a part of the gap into a part having a black color or a dark color close thereto.

According to the method for manufacturing a lens array provided by the fourth aspect of the present invention, it is possible to appropriately manufacture the lens array provided by the first aspect of the present invention.

In a preferred embodiment of the present invention, in the first step, resin molding operations for a plurality of lens arrays used in combination with each other are simultaneously performed by using a mold having a plurality of cavities. .

According to such a configuration, various conditions in the resin molding process of a plurality of lens arrays used in combination with each other can be made uniform. Therefore,
The lens arrays that are combined with each other can be made not to differ greatly in terms of dimensions, material, etc., and when these multiple lens arrays are used in combination, the lenses are accurately aligned on the same optical axis. It becomes possible.

In another preferred embodiment of the present invention,
The second step is a step of inserting a jig to which a paint of black color or a dark color close to this is adhered into the gap, and transferring the paint to a wall surface defining the gap.

According to such a configuration, a predetermined paint can be accurately and easily applied to the wall surface defining the void.

In another preferred embodiment of the present invention,
The method further comprises a step of masking the two surfaces for inputting and emitting light of the plurality of lenses, and then applying a black color or a similar dark color to the outer surface of the holder.

According to such a configuration, the outer surfaces of the holder portion can be covered with the light-shielding film made of a predetermined paint so that the two surfaces for inputting and emitting light of the plurality of lenses are not stained with the paint. .

[0063] Other features and advantages of the present invention will become more apparent from the following description of embodiments of the invention.

[0064]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be specifically described below with reference to the drawings.

FIG. 1 is a perspective view showing an example of a lens array according to the present invention. FIG. 2 is a sectional view taken along line X1-X1 of FIG. FIG. 3 is a sectional view taken along line X2-X2 of FIG. FIG. 4 is a bottom view of the lens array shown in FIG.

In FIG. 2, the lens array A of the present embodiment mainly includes a resin molded portion 5 obtained by molding a synthetic resin having a light transmitting property.
Constitute the holder portion 1 and the plurality of lenses 2. As the light-transmitting synthetic resin, for example, PMMA (polymethyl methacrylate (methacrylic resin)) or PC (polycarbonate) as an acrylic resin having high transparency is used. Also, this lens array A
Further includes a light-shielding film 4 that covers the outer surfaces of the plurality of light-shielding portions 3 and the holder portion 1. However, FIGS. 1 and 4
, The illustration of the light shielding film 4 is omitted.

The resin molded part 5 has a three-dimensional shape having a substantially rectangular parallelepiped portion extending in a certain direction and having an upper surface 5a and a lower surface 5b opposed to each other with an interval in the vertical thickness direction, and a plurality of the upper surface 5a and the lower surface 5b. The portions are partially convex surfaces 20a and 20b. The plurality of lenses 2 are formed in a region of the resin molded portion 5 where the convex surfaces 20a and 20b are formed, more strictly, these convex surfaces 20a and 20b.
A region having a predetermined height sandwiched between the upper and lower portions, and is a biconvex lens having the optical axis in the vertical thickness direction of the resin molded portion 4. Therefore, the surfaces 20a and 20b are portions corresponding to the light entrance / exit surfaces of each lens 2, and these may be spherical or aspherical.
The plurality of lenses 2 are arranged in a row at regular intervals in the longitudinal direction of the resin molded portion 5. On the other hand, the holder 1
Are the remaining portions of the resin molded portion 5 other than the regions of the plurality of lenses 2. Therefore, in the lens array A, there is no clear boundary line between the holder portion 1 and the plurality of lenses 2 as well shown in FIG. 1, the holder 1 surrounds the periphery of the plurality of lenses 2 so as to be integrally connected to the periphery of the plurality of lenses 2 and extends in the column direction of the plurality of lenses 2. It has a block shape.

As is clearly shown in FIG.
A convex portion 10a and a concave portion 10b are provided on the upper and lower surfaces of both ends in the longitudinal direction, respectively. These are parts used for positioning the lens array A when used in combination with another lens array. The protrusion 10a has a shape and a size that can be fitted into a recess formed in the same shape and size as the recess 10b.

The plurality of light shielding portions 3 are provided with a plurality of gaps 30 between the lenses 2 adjacent to each other, and a black coating film 31 is provided on each of a plurality of wall surfaces defining the plurality of gaps 30. It is constituted by that. Each gap portion 30 is provided so as not to penetrate in the thickness direction of the holder portion 1 by forming a concave groove of an appropriate depth on the lower surface 5b of the resin molded portion 5. As is clearly shown in FIG. 4, each gap portion 30 has a shape linearly extending by an appropriate dimension L in the lateral direction of the holder portion 1.

The light-shielding film 4 is provided by applying a black coating to a region other than the surfaces 20 a and 20 b of the lenses 2 on the outer surface of the resin molded portion 5. It is provided over the entire surface or almost the entire surface. The light-shielding film 4 and the coating film 31 constituting each light-shielding portion 3 can be provided by the same coating process as described later. However, these may be provided in a separate process.

Next, an example of a method for manufacturing the lens array A will be described with reference to FIGS.

FIGS. 5 and 6 are cross-sectional views of an essential part showing an example of a resin molding process of a lens array. 7 and 8
FIG. 3 is a sectional view of a main part showing an example of a coating process of a lens array. 9 and 10 are cross-sectional views of a main part showing another example of the coating process.

In order to manufacture the lens array A, the resin molded portion 5 as its original shape is first molded. This operation is performed, for example, by a pair of upper and lower molds 6a and 6b having a structure as shown in FIG.
This is performed using The molds 6a and 6b have a plurality of concave portions 20a 'and 20 corresponding to the convex surfaces 20a and 20b of each lens 2.
b ′, a plurality of wall surfaces 1 ′ for shaping the outer shape of the holder 1, and a plurality of convex portions 30 ′ for forming a plurality of voids 30. When a resin having translucency is filled into the cavity 61 from the supply path 60 of the molds 6a and 6b, and the resin is molded, as shown in FIG. Intermediate product can be obtained.

Next, a black coating is applied to the resin molded portion 5.
In this coating, first, as shown in FIG. 7, masks 49a and 49b are provided on the surfaces 20a and 20b of each lens 2. These masks 49a and 49b can be manufactured by using a technique of providing a photoresist limited to a certain region on the substrate surface in the semiconductor manufacturing field, for example. After such masking, the resin molded part 5 is immersed in a black paint liquid 48 as shown in FIG. Accordingly, black coating can be applied to all portions of the outer surface of the resin molded portion 5 except for the surfaces 20a and 20b of the lenses 2, and the light shielding film 4 and the light shielding portions 3 shown in FIG.
Can be simultaneously formed. Therefore, if the masks 49a and 49b are subsequently removed,
The lens array A is completed. The removal of the masks 49a and 49b can be performed by, for example, a method of etching them using an etching solution, or a method of mechanically separating them.

In the above-mentioned coating method, the coating operation on each part of the resin molded part 5 can be performed at once. However, in the above-described coating method, for example, when each of the gaps 30 is formed to have a very small width, it may take a relatively long time to allow the paint to enter the portion. In addition, the light-shielding film 4 should originally have a light-shielding property to prevent external light from entering the holder portion 1, whereas the coating film 31 of each light-shielding portion 3 is In some cases, it is desirable to apply a relatively rough black coating to the light-shielding film 4 and a dense black coating to the coating film 31 because the light passing directly through the light-shielding film 4 is directly affected.

Therefore, in such a case, for example, using a coating jig 8 as shown in FIG.
Paint on the wall surface that defines The jig 8 has a plurality of convex portions 80 having the same shape and size as the respective convex portions 30 'of the mold 6b described above. After the black paint 47 is adhered to the surfaces of the plurality of convex portions 80, and these are fitted into the respective gaps 30 of the resin molded portion 5 and then removed, as shown in FIG. It can be transferred to the entire surface of the wall surface that defines each void portion 30,
A coating 31 can be provided. In the present invention, a coating film 31 may be provided in each void portion 30 by such a coating method.

Next, an example of the lens array assembly according to the present invention will be described.

FIG. 11 is a perspective view showing an example of a lens array assembly according to the present invention. FIG. 12 is a cross-sectional view of the lens array assembly shown in FIG. FIG.
FIG. 3 is an explanatory diagram showing an operation of a lens of the lens array assembly shown in FIG.

In FIGS. 11 and 12, the lens array assembly B of this embodiment is configured by superposing a lens array A and another lens array Aa.
The basic configuration of the lens array Aa is common to the lens array A. Therefore, each part of the lens array Aa is denoted by the same reference numeral as that of each part of the lens array A, and description thereof is omitted.

However, the lens array Aa is obtained by molding the resin molding portion 5 in the same resin process as that of the lens array A by using the dies 6a and 6b shown in FIGS. More specifically, the mold 6
In addition to the cavities 61 for molding the original shape of the lens array A, cavities (not shown) for molding the original shape of the lens array Aa are provided in the a and 6b. Are molded simultaneously using the same resin material and mold as the resin molded portion 5 of the lens array A. By doing so, the conditions such as the components of the raw materials of the two lens arrays A and Aa and the shrinkage ratio during resin molding can be made the same. Therefore, it is preferable to reduce the dimensional error between the two lens arrays A and Aa and to accurately position the plurality of lenses 2.

The lens arrays A and Aa
By fitting the convex portions 10a of the lens array Aa into the concave portions 10b, positioning in the longitudinal direction and the width direction thereof is achieved. As means for ensuring the assembling of the lens arrays A and Aa, they may be bonded using, for example, an adhesive. 12, the respective lenses 2 of the lens arrays A and Aa are positioned so as to be aligned on the same optical axis C. In FIG. 12, since the light-shielding film 4 of each holder portion 1 is thickly illustrated, a large gap is formed between the two lenses 2 arranged on the optical axis C. Are thin and the gap between them is so small that the two lenses 2 come into contact with each other.

The two lenses 2 arranged on the same optical axis C are
As shown in FIG. 13, light traveling from points P ₁ , P ₂ , and P ₃ on the object surface is converted into points P ₁ ′, P ₂ ′, Focus on P ₃ '
It is possible to form an erect image of the same magnification. Such an erecting equal-magnification imaging action can be obtained not only when the curvatures of the surfaces 20a and 20b of the two lenses 2 to be combined are the same but also when they are different from each other.
Therefore, in the present invention, when constructing a lens array assembly for performing erecting equal-magnification imaging, it is possible to combine lens arrays formed such that the curvatures of the lens surfaces are different from each other. Absent.

FIG. 14 is a schematic cross-sectional view showing an example of an image reading apparatus constituted by using the lens array assembly according to the present invention.

The image reading apparatus D shown in FIG. 14 includes a transparent cover 70, a synthetic resin case 71 having the transparent cover 70 mounted on the upper surface, a substrate 72 mounted on the bottom of the case 71, and a This substrate 7 on the surface
2, a plurality of light sources 73 composed of, for example, LEDs, which are mounted in a row in the longitudinal direction (in FIG. 14, a direction orthogonal to the plane of the paper) and are arranged in a row in the same direction as the plurality of light sources 73. It is provided with a plurality of light receiving elements 74 arranged and mounted on the surface of the substrate 71, and the lens array assembly B described above. The plurality of light receiving elements 74
It has a photoelectric conversion function, and when receiving light, outputs a signal (image signal) of an output level corresponding to the amount of received light. The lens array assembly B includes a case 71
Are arranged between the plurality of light receiving elements 74 and the transparent cover 70 by being fitted into the concave grooves 75 provided in the
The plurality of light receiving elements 74 extend in a direction in which the light receiving elements 74 are arranged. A portion of the surface of the transparent cover 70 that faces each lens 2 of the lens array assembly B is a linear image reading target area S, and light emitted from the plurality of light sources 73 is formed on the case 71. The image reading target area S is illuminated by traveling along the illumination optical path 76. On the image reading target area S, for example, a platen roller 7
Documents G are sequentially transported by.

In the image reading apparatus D, the light emitted from the plurality of light sources 73 irradiates the surface of the original G on the image reading target area S, and when the light is reflected by the surface of the original G, the light is reflected. Light is received by lens array assembly B. Then, the reflected light is converged by the plurality of lenses 2 of the lens array assembly B, and an image of one line of the original G is formed on the plurality of light receiving elements 74 at an erect equal magnification. As shown in FIG. 12, each holder 1 of the lens array assembly B has its outer surface covered with a light-shielding film 4 made of black paint.
The reflected light can be prevented from passing through the inside of each holder portion 1 and reaching the plurality of light receiving elements 74. Therefore, the plurality of light receiving elements 74 can receive only the light transmitted through each lens 2 of the lens array assembly B.

As shown in FIG. 12, when the lens array assembly B receives light from above, the light actually enters each lens 2 of the lens array A from various directions.
For this reason, there is a case where light incident on one lens 2 of the lens array A travels as it is so as to cross the lens 2 in a direction intersecting the optical axis C. However, most of such light is blocked by the light shielding unit 3. Therefore, it is possible to prevent light that has entered one lens 2 from directly entering another lens 2 located next to the lens 2 as it is, so that so-called crosstalk between the plurality of lenses 2 can be prevented. The black coating film 31 of the light-shielding portion 3 absorbs most of the received light and does not scatter and reflect the received light toward the original lens 2. In addition, such an operation can be similarly obtained for the lens array Aa.

When the image reading device D is used, a change occurs in the temperature of the lens array assembly B and its surroundings. However, since the material of the resin molded portion 5 of each of the lens arrays A and Aa is the same and their linear expansion coefficients are the same, it is necessary to prevent the lens arrays A and Aa from being warped by the bimetal effect. it can. Further, the lens arrays A and Aa are in a state where displacement between the lens arrays A and Aa is unlikely to occur due to the fitting of the convex portions 10a and the concave portions 10b. Therefore, deviation of the optical axes of the lenses 2 of the lens arrays A and Aa can be avoided as much as possible. as a result,
The image of the original G can be clearly formed on the plurality of light receiving elements 74 using the lens array assembly B, and a high-resolution read image can be obtained.

Each of the lens arrays A and Aa constituting the lens array assembly B has a resin molded portion 5 in which the plurality of lenses 2 and the holder portion 1 are integrated by a resin molding process using dies 6a and 6b. Is manufactured by simply coating the resin molded portion 5 with the resin. Therefore, the manufacture of each of the lens arrays A and Aa, and the manufacture of the lens array assembly B combining these, are extremely simple, and the manufacturing cost can be reduced. For this reason,
The overall manufacturing cost of the image reading device D can be reduced.

FIG. 15 is a sectional view showing another example of the lens array assembly according to the present invention. Note that, in FIG. 15 and subsequent figures, the same portions as those in the previous embodiment or portions corresponding thereto are denoted by the same reference numerals, and description thereof is omitted.

The lens array assembly Ba shown in FIG.
It is configured by combining three lens arrays Ab, Ac, and Ad. These lens arrays Ab, Ac, Ad
Are basically the same as those of the lens array A. However, each lens 2 of the lens arrays Ab, Ac, Ad is a spherical lens whose convex surfaces 20a, 20b are spherical.

As described above, the present invention may be configured to combine three lens arrays Ab, Ac, and Ad. Even in such a configuration, it is possible to perform erecting equal-magnification imaging by three lenses 2 arranged on the same axis C. In addition, as compared with the case where only two lens arrays are combined, the curvature of the surfaces 20a and 20b of each lens 2 required for performing erecting equal-magnification imaging can be reduced. Therefore, by reducing the curvature, the aberration of each lens 2 can be reduced, and the formed image can be made clearer accordingly. Of course, in the present invention, a configuration in which four or more lens arrays are combined may be employed.

In the lens array assembly Ba, since all of the plurality of lenses 2 are spherical lenses, the overall manufacturing cost is reduced by the use of an aspherical lens which is more complicated to mold than a spherical lens. It can be cheaper.
However, the present invention is not limited to this. For example, all or any of the lenses 2 of the lens arrays Ab, Ac, and Ad may be aspherical lenses. By doing so, the spherical aberration of the lens can be eliminated or reduced, and the formed image can be made clearer.

FIG. 16 is a sectional view showing another example of the lens array according to the present invention. FIG. 17 is a sectional view showing an example of a lens array assembly using the lens array shown in FIG.

The lens array Ae shown in FIG. 16 is a lens array in which each lens 2A is a concave lens having concave surfaces 20c and 20d, and in this point, the configuration is different from the lens array described above. . The surfaces 20c and 20d are
It may be spherical or aspherical.

The lens array assembly Bb shown in FIG.
A lens array Ae between two lens arrays Af and Ag
Are sandwiched between them, and these are combined. Each of the two lens arrays Af and Ag has its lens 2 formed as a convex lens. In addition, 2
The material of each lens 2 of the two lens arrays Af and Ag is, for example, PMMA, whereas the material of each lens 2A of the lens array Ae is, for example, PC. The numbers (the reciprocals of the dispersibility) are also different.

In the lens array assembly Bb, the three lenses 2, 2A, 2 arranged on the same optical axis C are a combination of a convex lens and a concave lens having different Abbe numbers. Can be an achromatic lens. More specifically, chromatic aberration caused by the two lenses 2 serving as convex lenses can be removed by the lens 2A serving as a concave lens. Of course, even when a convex lens and a concave lens are combined, it is possible to perform erecting equal-magnification imaging. Therefore, the lens array assembly Bb is optimal for use in forming a color image.

As described above, in the lens array according to the present invention, the lens may be either a convex lens or a concave lens. Further, the lens array assembly according to the present invention is not limited to a combination of lens arrays of convex lenses, and may be a combination of a convex lens array and a concave lens array. Further, each lens of the lens array may be a one-convex lens or a one-concave lens in which one of the two surfaces for light input and output is a flat surface.

FIG. 18 is a perspective view showing another example of the lens array according to the present invention. FIG. 19 is a plan view of a main part of the lens array shown in FIG. FIG.
It is 3-X3 sectional drawing. FIG. 21 is a view showing the relationship between X4 and X4 in FIG.
It is sectional drawing.

The lens array A shown in FIGS.
h is a plurality of voids 3 provided in the resin molded part 5A.
0A each penetrates in the vertical thickness direction of the holder portion 1A. As shown in FIG. 19, each of the gaps 30A has a substantially arc shape in a plan view, and the gaps 30A adjacent to each other are connected to each other in a back-to-back manner. In the drawings, from the viewpoint of facilitating understanding of the structure of the lens array Ah, each gap 30A is drawn as having a relatively large opening width, but preferably each gap 30A is formed with the smallest possible opening width. Therefore, most of the light traveling from above or below the lens array Ah is unlikely to pass through each gap 30A.

In the resin molded portion 5A, a plurality of substantially circular portions in plan view surrounded by gaps 30A adjacent to each other are individual lenses 2B, and the other portions are holder portions 1A. ing. A part of each lens 2B has a part of its outer periphery formed by a gap 30A, and is separated from the holder 1 via the gap 30A. However, each lens 2B is provided on the outer periphery of each lens 2B.
Two narrow rib-shaped connecting portions 21 for connecting B to the holder portion 1A are provided continuously, and each lens 2B is integrated with the holder portion 1A via these connecting portions 21. , And is supported by the holder 1A. As is clearly shown in FIG. 20, the outer peripheral surface 22 of each lens 2B except for the connecting portion 21 is formed as a tapered surface.
Has a smaller diameter toward one end in the optical axis direction, that is, toward the lower end in FIG.

A black coating film 31A is provided on the wall surface defining each void portion 30A, and this portion is
It has become. Since the outer peripheral surface 22 of each lens 2B corresponds to a part of the wall surface defining each gap 30A, the outer peripheral surface 22 of each lens 2B is directly provided with the coating film 31A. As shown in FIG. 18, a plurality of recesses 10 c are formed on the bottom of the holder 1 </ b> A.
Are provided at appropriate intervals in the longitudinal and width directions. These concave portions 10c are portions used for positioning the lens array Ah when the lens array Ah is used in combination with another lens array. 20 and 21
, A black light-shielding film 4 is also provided on the entire or substantially entire outer surface of the holder portion 1A. The light-shielding film 4 and the coating film 31A of the light-shielding portion 3A can be provided by the same operation as the above-described operation of providing the light-shielding film 4 and the coating film 31 of the lens array A.

FIG. 22 and FIG. 23 are cross-sectional views of essential parts showing another example of the resin molding process of the lens array.

As shown in these figures, the lens array A
The resin molded portion 5A serving as the original shape of h can be molded using a pair of dies 6c and 6d. That is,
As the molds 6c and 6d, the surfaces 20a and 20
0b, a plurality of recesses 20a ', 20b',
What has a plurality of wall surfaces 1A 'defining the outer shape of A and a plurality of convex portions 30A' for forming a plurality of void portions 30A may be used. Since each lens 2B has a tapered shape having a smaller diameter toward the lower end, the convex portion 30A 'that defines the outer peripheral shape of each lens 2B should be tapered such that the thickness t increases toward the lower end. Can be. Therefore, in order to form each of the gaps 30A with a narrow width, it is necessary to form each of the convex portions 30A ′ thin.
If the thickness t of the lower end portion of 0A 'can be increased, each convex portion 30
A 'can be given strength, which facilitates die production.

FIG. 24 is a perspective view showing another example of the lens array assembly according to the present invention. FIG. 25 is an exploded perspective view of the lens array assembly shown in FIG. FIG.
FIG. 25 is a sectional view of the lens array assembly shown in FIG. 24.

The lens array assembly Bc shown in these figures
Is constructed by superposing another lens array Ai under the lens array Ah. The basic configuration of the lens array Ai is common to the lens array Ah. For this reason, each part of the lens array Ai is denoted by the same reference numeral as that of the lens array Ah. However, the lens array Ai has a plurality of concave portions 10 of the lens array Ah.
c, a plurality of projections 10d which can be engaged or fitted into
0c is provided instead. Two lens arrays A
As shown in FIG. 26, h and Ai are combined such that their respective lenses 2B are aligned on the same optical axis C by the positioning operation of the concave portions 10c and the convex portions 10d.

Each of the lenses 2B of the two lens arrays Ah and Ai has a single lens 2B because its outer peripheral surface 22 is surrounded by a light shielding portion 3A made of a black coating film 31A.
Even if the light incident on B reaches the outer peripheral surface 22, this light is absorbed by the light shielding portion 3A. Therefore, it is possible to prevent light scattering and reflection from occurring in each lens 2B. Further, the light-shielding portion 3A also has a function of preventing light traveling into each lens 2B from being incident on another lens 2B located next to the lens 2B. Therefore, the so-called crosstalk between the lenses can be prevented.

As described above, according to the present invention, the gap 30A
Is provided so as to penetrate through the holder 1A, crosstalk between lenses can be prevented. Therefore, in the present invention, it is possible to adopt any configuration of the case where the gap portion penetrates the holder portion and the case where the gap portion does not penetrate the holder portion. However, in the case where the gap does not penetrate through the holder, as can be understood from the shapes of the dies 6a and 6b shown in FIG.
0 can be prevented from being blocked at a large rate by the convex portion 30 ′, and the entire area of the cavity 61 can be easily filled with the raw material resin. on the other hand,
If the gap portion penetrates the holder portion, the area of the wall surface defining the gap portion, and the area of the light-shielding portion formed by coating the wall surface can be increased, and the distance between the lenses is wide. Can be blocked by area. However, even when the gap does not penetrate through the holder, the width of the light shielding portion is reduced by painting the wall surface (for example, the surface indicated by reference numeral 3a in FIG. 2) that defines the bottom or upper portion of the gap. In this case, it is possible to precisely optically separate the lenses from each other.

FIGS. 27 to 29 are plan views showing the principal parts of another example of the lens array according to the present invention.

In the lens array Aj shown in FIG. 27, gaps 30A adjacent to each other are formed separately. In the lens array Ah of the above embodiment, since the gaps 30A adjacent to each other are connected, an advantage that the arrangement pitch of the plurality of lenses 2B can be extremely reduced is obtained. On the other hand, when the arrangement pitch of the lenses 2B does not need to be very small, a configuration like the lens array Aj may be used.

In the lens array Ak shown in FIG. 28, each lens 2B is connected to the holder 1A via only one connecting portion 21.
Is connected to. As described above, in the present invention, when the outer periphery of the lens 2B is formed by the gap 30A penetrating the holder 1A, at least one or more connecting portions 21 are connected to each lens 2B and the holder 1A. What is necessary is just to be connected to each other through. In the present invention, each lens 2
As long as the support of B is not hindered, as the number of connecting portions 21 is reduced and the width of connecting portion 21 is reduced, the area of outer peripheral surface 22 of each lens 2B separated from holder 1A and the outer peripheral surface are reduced. It is possible to increase the area of the light shielding portion provided in the lens 22, and to improve the optical characteristics of each lens 2B.

In the lens array Al shown in FIG. 29, the gap 30A surrounding the outer peripheral surface 22 of each lens 2B is formed to have a considerably large opening width. The present invention may be formed in this manner. However, if the lens array Al is used while the gap 30A is largely opened, a large amount of light may pass through the gap 30A, which may cause a problem. In order to solve such a problem, when the lens array Al is used, for example, the opening of the gap 30A may be closed by using an appropriate member to prevent light from passing through the gap 30A. .

FIGS. 30, 31, and 33 are sectional views showing other examples of the lens array according to the present invention. FIG. 32 is a fragmentary cross-sectional view showing a step for manufacturing the lens array shown in FIG.

The lens array Am shown in FIG. 30 has a structure in which a light shielding portion 3B is provided by filling or inserting a black substance or member 32 into a gap portion 30 provided between each of a plurality of lenses 2. It has been. Even with such a configuration, the light-shielding portion 3B absorbs much of the received light and prevents or suppresses crosstalk between the plurality of lenses 2 as in the case where the wall surface of the gap portion 30 is painted black. Can be achieved. In order to enhance the light absorbing effect of the light-shielding portion, it is most preferable that the color of the light-shielding portion be black, and then it is preferable that the color of the light-shielding portion be close to that, but the specific color of the light-shielding portion referred to in the present invention is It is not particularly limited.

In the lens array An shown in FIG. 31, no gap is formed between each of the plurality of lenses 2, and the whole or a part of the black member 33 is embedded in the resin molded part 5B. The member 33 has a structure in which a plurality of light shielding portions 3C located between the respective lenses 2 are configured. As shown in FIG. 32, the resin molded portion 5B is molded by insert molding in which the member 33 is disposed in the cavity of the pair of dies 6e and 6f. The member 33 includes a plurality of upright portions 3 arranged in a row at regular intervals.
3a are connected in series via a connecting portion 33b,
The connecting portion 33b is provided with a plurality of holes 33c so as not to hinder the molding of the lens 2. According to such a resin molding process, it is possible to easily obtain a lens array An in which the plurality of upright portions 33a are the light-shielding portions 3C located between the plurality of lenses 2, and after molding the resin molded portion 5B. It is possible to eliminate the necessity of performing a coating process, a member inserting operation, and the like for providing the light shielding portion. Although the resin molded portion 5B is molded by insert molding,
In this molding operation, the member 33 which has been made into a single part is
Since it can be easily set and set in the 6f, it is much easier than the conventional molding operation in which a plurality of lenses are arranged in a mold, and also achieves the object of the present invention. Can be.

In the lens array Ao shown in FIG. 33, in the holder portion 1B, an area corresponding to each space between the plurality of lenses 2 is processed as an opaque area having a black color or a dark color close thereto, and this area is shielded from light. It has a configuration that is a part 3D. As a method of treating a part of the holder portion 1B as opaque, for example, a method of molding the lens array Ao with a photosensitive resin and applying a light beam of a specific wavelength to the resin to make the part opaque is adopted. Is possible.

As described above, in the present invention, it is possible to provide the light shielding portion between each of the plurality of lenses by various means, and the specific means is not limited. Further, in the present invention, as a means for optically separating a plurality of lenses, it is preferable to use a light-absorbing light-shielding portion. However, the means is not limited to this. The case where the present invention is merely included is included in the technical scope of the present invention. Furthermore, in the lens array according to the present invention, the optical separation between the plurality of lenses does not have to be completely performed. In short, the lens array includes means for optically separating the plurality of lenses. It is only necessary that the configuration be such that crosstalk between a plurality of lenses can be prevented or suppressed.

FIG. 34 is a partially omitted schematic perspective view showing another example of the lens array according to the present invention.

In the lens array Ap shown in FIG. 19, a holder 1C is formed in a rectangular plate shape in a plan view, and a plurality of lenses 2 are arranged at predetermined intervals in the vertical and horizontal directions of the holder 1C. I have. According to such a configuration, a function of forming an image of a planar area having a fixed area can be provided. When two or more lens arrays Ap are combined, the assembly is used to form an image displayed on a display such as a CRT or a liquid crystal display on an area in front of the display at an erect magnification of 1: 1. Can be used. As described above, in the present invention, the specific shape of the holder portion, the specific arrangement of the plurality of lenses, and the like can be variously changed, and the specific use of the lens array and the lens array assembly can be changed. These items can be arbitrarily selected accordingly.

The specific configuration of each part of the lens array, the lens array assembly, and the intermediate product of the lens array according to the present invention is not limited to the above-described embodiment, and various design changes can be made. Similarly, the specific configuration of the lens array manufacturing method according to the present invention can be variously changed. The lens array assembly is not capable of forming an erect 1: 1 image,
It may be configured with different characteristics. Further, the entire or substantially entire outer surface of the holder portion of the lens array is covered with a light-shielding member having a light-shielding function, such as a black sheet, instead of a light-shielding layer made of black or a dark-colored paint near it. It may be configured. However, the holder portion of the lens array may be configured so as not to be covered by the light shielding member or the light shielding layer.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of a lens array according to the present invention.

FIG. 2 is a sectional view taken along line X1-X1 of FIG.

FIG. 3 is a sectional view taken along line X2-X2 of FIG.

FIG. 4 is a bottom view of the lens array shown in FIG.

FIG. 5 is a sectional view of a main part showing an example of a resin molding process of a lens array.

FIG. 6 is a cross-sectional view of a main part showing an example of a resin molding step of a lens array.

FIG. 7 is a cross-sectional view of an essential part showing an example of a coating process of a lens array.

FIG. 8 is a cross-sectional view of a main part showing an example of a coating process of a lens array.

FIG. 9 is a cross-sectional view of a main part showing another example of a coating process.

FIG. 10 is a cross-sectional view of a main part showing another example of the coating process.

FIG. 11 is a perspective view showing an example of a lens array assembly according to the present invention.

FIG. 12 is a sectional view of the lens array assembly shown in FIG. 11;

FIG. 13 is an explanatory diagram showing an operation of the lens of the lens array assembly shown in FIG. 11;

FIG. 14 is a schematic cross-sectional view illustrating an example of an image reading device configured using the lens array assembly according to the present invention.

FIG. 15 is a sectional view showing another example of the lens array assembly according to the present invention.

FIG. 16 is a sectional view showing another example of the lens array according to the present invention.

FIG. 17 is a sectional view showing an example of a lens array assembly using the lens array shown in FIG.

FIG. 18 is a perspective view showing another example of the lens array according to the present invention.

FIG. 19 is a plan view of a main part of the lens array shown in FIG. 18;

20 is a sectional view taken along line X3-X3 of FIG.

21 is a sectional view taken along line X4-X4 of FIG.

FIG. 22 is a fragmentary cross-sectional view showing another example of the lens array resin molding step.

FIG. 23 is a fragmentary cross-sectional view showing another example of the resin molding process of the lens array.

FIG. 24 is a perspective view showing another example of the lens array assembly according to the present invention.

FIG. 25 is an exploded perspective view of the lens array assembly shown in FIG. 24.

FIG. 26 is a cross-sectional view of the lens array assembly shown in FIG.

FIG. 27 is a main part plan view showing another example of the lens array according to the present invention.

FIG. 28 is a plan view of relevant parts showing another example of the lens array according to the present invention.

FIG. 29 is a plan view of relevant parts showing another example of the lens array according to the present invention.

FIG. 30 is a sectional view showing another example of the lens array according to the present invention.

FIG. 31 is a sectional view showing another example of the lens array according to the present invention.

32 is a fragmentary cross-sectional view showing a step for manufacturing the lens array shown in FIG. 31.

FIG. 33 is a sectional view showing another example of the lens array according to the present invention.

FIG. 34 is a partially omitted schematic perspective view showing another example of the lens array according to the present invention.

FIG. 35 is a perspective view showing an example of a conventional lens array.

FIG. 36 is a sectional view of a main part of the conventional lens array shown in FIG.

[Explanation of symbols]

 A, Aa to Ao Lens array B, Ba to c Lens array assembly C Optical axis 1, 1A to 1C Holder 2, 2A, 2B Lens 3, 3A to 3C Light shield 4 Light shield layer 5, 5A to B Resin molding 5a Upper surface 5b Lower surface 6a-6f Mold 10a Convex part (positioning means) 10b Concave part (positioning means) 10c Concave part (positioning means) 10d Convex part (positioning means) 20a-20d Both sides (of lens) 22 Outer peripheral surface (of lens) 30, 30A gap

Claims (27)

[Claims] 1. A lens array comprising a plurality of lenses and a holder for connecting the plurality of lenses, wherein the plurality of lenses and the holder are made of a synthetic resin having a light-transmitting property. A lens array, which is integrally formed and has means for optically separating the plurality of lenses. 2. A resin molded part having an upper surface and a lower surface facing each other at an interval in a thickness direction and having a plurality of convex or concave surfaces on at least one of the upper surface and the lower surface, In the resin molded portion, regions where the convex or concave surface is formed are the respective lenses, and
The remaining area is the holder section.
2. The lens array according to 1. 3. The light-absorbing light-shielding portion provided so as to block between the plurality of lenses, wherein the means for optically separating the plurality of lenses is provided. 2. The lens array according to 1. 4. The light-shielding portion is formed by providing a gap between each of the plurality of lenses and applying a black color or a near-dark color to the wall surface that defines the gap. The lens array according to claim 3. 5. The light-shielding portion is formed by providing a gap between each of the plurality of lenses, and by inserting a substance or a member having a black color or a dark color near the gap in the gap. The lens array according to claim 3. 6. The lens array according to claim 4, wherein the gap is provided so as not to penetrate the holder. 7. The lens array according to claim 4, wherein the gap is provided so as to penetrate the holder. 8. The lens array according to claim 4, wherein the gap extends linearly in a direction intersecting a direction in which the plurality of lenses are arranged. 9. The air gap according to claim 4, wherein the gap is provided so as to separate a part of the outer periphery of each lens from the holder and form a substantially cylindrical shape. Lens array. 10. The lens array according to claim 9, wherein the gap is provided such that the diameter of each lens becomes smaller as the diameter of the lens becomes one end in the optical axis direction. 11. The lens array according to claim 3, wherein the light-shielding portion is formed of a member of a black color or a color of a dark color similar to black embedded in the holder portion. 12. The lens array according to claim 3, wherein the light-shielding portion is formed by processing a part of the holder portion to a black color or a dark color close thereto. 13. An entire or substantially entire outer surface of the holder portion is covered with a light shielding film or a light shielding member.
The lens array according to claim 1. 14. The apparatus according to claim 1, wherein the plurality of lenses are arranged in a line at a predetermined interval, and the holder is formed as a block extending in the same direction as the rows of the plurality of lenses. 14. The lens array according to any one of 13. 15. The method according to claim 1, wherein the plurality of lenses are arranged vertically and horizontally at a predetermined interval, and the holder is formed in a plate shape extending in an arrangement direction of the plurality of lenses. The lens array according to any one of the above. 16. A plurality of lens arrays according to claim 1, wherein the plurality of lens arrays are overlapped with each other such that the lenses are arranged on the same optical axis. Characterized by
Lens array assembly. 17. The lens array assembly according to claim 16, wherein said plurality of lens arrays are capable of forming an erect image of equal magnification. 18. The lens array assembly according to claim 16, wherein said plurality of lens arrays are provided with positioning means for fitting or engaging with each other so as to position said plurality of lens arrays. Goods. 19. The lens array assembly according to claim 16, wherein all lenses of said plurality of lens arrays are spherical lenses. 20. The lens array assembly according to claim 16, wherein at least one lens of the plurality of lens arrays is an aspheric lens. 21. The lens array assembly according to claim 16, wherein the number of the plurality of lens arrays is three or more. 22. The lens array assembly according to claim 16, wherein at least two or more convex lens arrays are combined with at least one or more concave lens arrays having different Abbe numbers. 23. A plurality of lenses and a holder connecting the plurality of lenses are integrally formed of a synthetic resin having a light-transmitting property, and a gap is provided between each of the plurality of lenses. An intermediate product of a lens array. 24. A first method in which a gap is provided between each of a plurality of lenses, and the plurality of lenses and a holder portion connecting the plurality of lenses are integrally formed of a synthetic resin having a light-transmitting property. A method of manufacturing a lens array, comprising: a step of processing at least a part of the gap into a part having a black color or a dark color close thereto. 25. The method according to claim 24, wherein in the first step, a resin molding operation is performed on a plurality of lens arrays used in combination with each other by using a mold having a plurality of cavities. A method for manufacturing a lens array. 26. A step of inserting a jig to which a paint of black color or a dark color close to the black is adhered into the gap, and transferring the paint to a wall surface defining the gap. The method for manufacturing a lens array according to claim 24 or 25, wherein 27. A step of applying masking to two surfaces for inputting and outputting light of the plurality of lenses, and then applying black or a dark color similar to the outer surface of the holder. A method for manufacturing a lens array according to any one of claims 24 to 26.