JP2000316069A - Manufacture of lens array and lens array - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently and inexpensively provide lens arrays superior in an optical characteristic by forming a resin molded good where plural lenses are arranged in plural columns and are integrally connected with synthetic resin having translucency and dividing the resin molded good as plural lens arrays where the plural lenses are arranged in columnar forms. SOLUTION: A resin molded good 1' is made into a plate form or a sheet form whose outline form is rectangular and it is formed by synthetic resin having translucency. Plural lenses 11 are constituted so that confronted concave curve faces are formed in plural parts on the surface and the rear face of the resin molded good 1' and are the double convex lenses where the concave curve faces are set to be faces for light incident/ejection. The cutting work of such resin molded good 1' is executed. The cutting work can be executed by sequentially or simultaneously cutting the resin molded good 1' along the virtual lines of codes Nb-Nb, which are equivalent to the band-like areas 1e of plural rows between lens columns. The plural lens arrays 1 of long block forms can be obtained with such cutting work.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a lens array and a lens array.
For example, in an optical device such as a contact type image sensor, a method of manufacturing a lens array for manufacturing a lens array used for forming an image of a document on light receiving elements arranged in a line and a method of manufacturing the same The present invention relates to a lens array manufactured by the method.

[0002]

2. Description of the Related Art As is well known, in a line image sensor, 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 the main scanning direction. 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. The lens array 9 has a plurality of cylindrical SELFOC lenses (rod lenses) 91 held in an elongated block-like holder 90 extending in a certain direction.
Numerals 1 are arranged in a row at regular intervals in the longitudinal direction of the holder portion 90. As shown in FIG. 18, each SELFOC lens 91 is, for example, an erect equal-magnification image a ′ → b ′ of an object a → b.
It is possible to obtain

[0004] Each SELFOC lens 91 has a different internal refractive index such that the refractive index inside the SELFOC lens increases radially outward so as to meander the incident light. 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. The holder part 90 is formed by resin molding so as to be embedded in the holder.

[0005]

However, in the above-described conventional manufacturing method, the steps of manufacturing the lens and the step of molding the resin of the holder are performed separately, so that the operations are very complicated. Had become. In particular, the individual lenses are generally of a very small size, and the total number of lenses used in one lens array is large. The operation of positioning and arranging a large number of lenses at predetermined positions in a mold has been extremely troublesome. Therefore, conventionally, the productivity of the lens array is low and the manufacturing cost is high.

Conventionally, there is also a lens array in which a lens different from a SELFOC lens, for example, a plurality of convex lenses made of glass or a lens made of optical fibers cut to a certain size is embedded in a resin holder. is there.
However, even in such a lens array, similarly to the above-described Selfoc lens, after manufacturing a large number of lenses individually, the lens array is manufactured so as to be buried in the holder portion using an insert molding technique. Therefore, there is a problem that the manufacturing cost is high, as in the case described above.

The present invention has been conceived under such circumstances, and it is an object of the present invention to manufacture a lens array having excellent optical characteristics with good production efficiency and at low cost.

[0008]

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

A method for manufacturing a lens array provided by a first aspect of the present invention is a resin molding method in which a plurality of lenses having a convex or concave surface for light input / output are arranged in a plurality of rows and connected integrally. A resin molding step of molding the article with a translucent synthetic resin, and a dividing step of dividing the resin molded article into a plurality of lens arrays in which a plurality of lenses are arranged in a row. Features.

According to the lens array manufacturing method provided by the first aspect of the present invention, the following effects can be obtained.

First, a resin molded product in which a plurality of lenses are arranged in a plurality of rows can be easily manufactured by a normal resin molding process using a mold, and the resin molded product is divided. Thereby, a plurality of lens arrays can be obtained from one resin molded product. Therefore, according to the present invention, a plurality of lenses are manufactured separately from the holder portion and then incorporated in the holder portion, so that the lens array has a smaller size than the conventional manufacturing method in which the lens arrays are manufactured one by one. The productivity can be dramatically improved, and the manufacturing cost of the lens array can be reduced.

Second, in the present invention, since the entire volume of the resin molded product is larger than the volume of each lens array finally obtained, the molten resin is supplied into the mold to perform the resin molding. It is possible to improve the flow of the resin when molding the product. Therefore, the light input / output surface of the lens of the lens array and other densely shaped portions can be appropriately formed, and the lens array can be made thinner and narrower.

Third, when it is desired to perform a desired process such as a coating process or a machining process on each of a plurality of lens arrays, if the process is performed at the stage of a resin molded product, a plurality of lens arrays are substantially formed. This is the same as performing a predetermined process collectively on each of the lens arrays. Therefore, it is possible to further increase the productivity of the lens array.

Fourth, a plurality of lens arrays obtained by separating one resin molded product are resin molded under the same or substantially the same conditions by using the same mold. Thus, for example, it is possible to manufacture the lens arrays so that the lens pitches of the plurality of lens arrays do not significantly shift from each other. Therefore,
For example, by combining a plurality of lens arrays, it is possible to obtain an effect that the optical axes of the lenses can be accurately aligned when used to form an erect life-size image of an object. Become.

In a preferred embodiment of the present invention, at least one side edge of the outer periphery of the resin molded product is thicker than a portion where a plurality of lenses are arranged in a row.

According to such a configuration, when the resin molded product is molded using a mold, the flow of the resin in the portion where the thickness of the outer peripheral edge of the resin molded product is large is improved. Therefore, it becomes easy to spread the resin around the entire area in the mold, and it is possible to more appropriately mold the resin molded product.

In another preferred embodiment of the present invention, the resin molded product has a concave groove for blocking between adjacent lenses in the column direction of the lenses.

According to such a configuration, the plurality of lenses of the lens array can be optically separated from each other by using the concave grooves. That is, for example, it is possible to prevent the light incident on one lens from being mixed (crosstalk) into the adjacent lens by the concave portion. Therefore, it is possible to prevent the optical function of the lens array from being deficient due to the lens array being formed of a translucent synthetic resin.

In another preferred embodiment of the present invention, the concave groove is provided on each of a front surface and a rear surface of the resin molded product.

According to such a configuration, when the groove serves as a means for preventing crosstalk between lenses adjacent to each other, individual grooves are formed in comparison with the case where grooves are formed only on one surface of a resin molded product. The depth of the concave groove can be reduced. Therefore, when the concave groove of the resin molded product is formed using a mold, the protrusion dimension of the convex portion of the mold for forming the concave groove can be reduced. This is preferable in facilitating the manufacture of the mold and facilitating the flow of the resin in the mold.

In another preferred embodiment of the present invention, prior to the dividing step, the whole or a part of the area of the resin molded product excluding the light input / output surface of each of the lenses is made black or nearly black. There is a coating step of coating with a dark-colored light shielding material.

According to such a configuration, in the manufactured lens array, light enters into each lens from a region other than the light input / output surface of the plurality of lenses, or travels through each lens. It is possible to appropriately prevent the light from being emitted to the outside from a region other than the light input / output surface of each lens.

In another preferred embodiment of the present invention, the coating step comprises applying a black or near dark paint to the entire surface or substantially the entire surface of the resin molded product, and then entering and exiting the light of each lens. This is a step of removing the paint applied to the working surface before drying and curing.

According to such a configuration, the coating step is simplified, and the workability can be improved.

In another preferred embodiment of the present invention, each lens of the resin molded article has an outer peripheral surface rising from a peripheral portion of each lens.

According to such a configuration, a step is formed between the entire light input / output surface of each lens and the peripheral portion of each lens. Therefore, after the paint is applied to the entire surface or almost the entire surface of the resin molded product, for example, when the paint applied to the light input / output surface of each lens is removed using an appropriate wiping member, the portion of the portion is removed. The operation of removing only the paint is facilitated.

According to a second aspect of the present invention, there is provided a lens array. This lens array is characterized by being manufactured by the method for manufacturing a lens array provided by the first aspect of the present invention. According to the lens array having such a configuration, the same effect as obtained by the first aspect of the present invention can be expected.

The other features and advantages of the present invention will become more apparent from the following description of embodiments of the present invention.

[0029]

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

FIG. 1A is a plan view showing an example of a resin molded product as an intermediate product of the lens array, and FIG.
Is a sectional view taken along the line II. FIG. 2 is a sectional perspective view of a main part of the resin molded product shown in FIG. FIG. 3 is an enlarged sectional view of a main part of the resin molded product shown in FIG.

To manufacture a lens array, first, FIGS.
A resin molded product 1 'having a configuration as shown in FIG. 3 is manufactured. The resin molded product 1 'has a rectangular plate-like or sheet-like shape as a whole, and is made of a light-transmitting synthetic resin. As a specific material, PMMA (polymethyl methacrylate (methacrylic resin)) or PC (polycarbonate) having excellent transparency and mechanical strength is suitably adopted. The resin molded product 1 'has a configuration including a plurality of lenses 11, a plurality of concave grooves 14, a plurality of convex portions 12, and a plurality of concave portions 13.

The plurality of lenses 11 are formed on a plurality of convex and concave surfaces 11 opposing each other at a number of locations on the front and back surfaces of the resin molded product 1 ′.
a, 11b, and is a biconvex lens having these convex curved surfaces 11a, 11b as light input / output surfaces (hereinafter abbreviated as “lens surfaces”). The lens surfaces 11a and 11b may be spherical or aspherical, and if they are spherical, their manufacture is facilitated. On the other hand, if the lens surfaces 11a and 11b are made aspherical, it is possible to reduce aberration and form an image with less out-of-focus. The plurality of lenses 11 are arranged in a row at a constant pitch in the longitudinal direction (horizontal direction in FIG. 1A) of the resin molded product 1 ′. For example, a total of 10
They are arranged in multiple columns. The diameter of each lens surface 11a, 11b is, for example, 0.6 mm, and the pitch of the lenses 11 in the lens row direction is, for example, 0.75 mm. The total length of each lens row is set to be slightly longer than 210 mm so as to correspond to, for example, an A4 size document width.

As is best seen in FIGS. 2 and 3,
Each lens 11 has an appropriate size Lb from its peripheral surface.
(E.g., about several tenths of a millimeter)
c, 11d. Accordingly, there is a step having the above-mentioned dimension Lb between the peripheral edge of the lens surfaces 11a and 11b of each lens 11 and the surface of the resin molded product 1 'in the region surrounding the periphery of each lens 11.

The plurality of concave grooves 14 are located between the lenses 11 adjacent to each other in the lens row direction, and are provided on both the front and back surfaces of the resin molded product 1 ′. Each of the grooves 14 is, for example, a bottomed groove that is opened in a slender rectangular shape extending in a direction intersecting with the row direction of the plurality of lenses 11.

The plurality of convex portions 12 and concave portions 13 are portions used for assembling a plurality of lens arrays manufactured from the resin molded product 1 ', as described later. The plurality of convex portions 12 are formed on the surface of the resin molded product 1 ′.
It is provided on both sides of each lens row. Multiple recesses 13
Are provided on the back surface of the resin molded product 1 ′ at positions facing the plurality of projections 12.

In FIG. 1A, a resin molded product 1 'is
A region other than the region of the total of ten lens rows in which the plurality of lenses 11 are arranged in a row is a thick portion having a larger thickness than the region of the lens rows. More specifically, in addition to the side edges 1a and 1b at both ends in the longitudinal direction of the resin molded product 1 'provided with the plurality of convex portions 12 and the concave portions 13, the lateral edges of the resin molded product 1' are arranged in the lateral direction. The thickness of the plurality of strip-like regions 1e provided between the portions 1c and 1d and the plurality of lens rows is formed to be thicker than the region where the plurality of lenses 11 are arranged.

The production of the resin molded product 1 'having the above-described structure is as follows.
For example, as shown in FIG. 4 and FIG.
a, 6b. The dies 6a and 6b are configured by combining the dies main portions 60a and 60b and the auxiliary dies 61a and 61b. More specifically, the mold body portions 60a and 60b have a plurality of concave portions 11a 'and 11b' corresponding to each lens surface 11a and 11b of the resin molded product 1 'on the surface for forming the cavity 65. It is provided in a row and has a concave portion 12 'and a convex portion 13' for forming the convex portion 12 and the concave portion 13 of the resin molded product 1 '. As shown in FIG. 6, the auxiliary dies 61a and 61b are provided with a plurality of convex portions 64 on the surface of a band-shaped member 63 having a large number of through holes 62 formed therein. is there. The plurality of convex portions 64 are members for forming the concave grooves 14 of the resin molded product 1 '. These auxiliary dies 61a, 6
1b has a plurality of through holes 62 formed of a plurality of recesses 11a ', 11b'.
Are attached to the mold body portions 60a and 60b so as to overlap with.

The cavities 6 of the dies 6a and 6b having the above-described structure.
When a resin having translucency is filled in the mold 5 and the molding is performed, a resin molded product 1 ′ having the above-described configuration can be obtained. The through-holes 62 of the auxiliary dies 61a and 61b correspond to the outer peripheral surfaces 11c and 11d of each lens 11 shown in FIGS.
And serves to conveniently form a short cylindrical portion surrounded by The resin molded product 1 'has a larger overall size and a larger volume of the cavity 65 of the molds 6a and 6b than the individual lens array finally obtained. Therefore, when the resin is poured into the cavity 65,
The flow of the resin in the cavity 65 becomes good, and fine parts such as the wall surfaces defining the lens surfaces 11a and 11b and the concave grooves 14 can be appropriately molded. In particular,
As described above, since the area other than the lens row area is thick in the resin molded product 1 ′, it is appropriate to allow the resin supplied into the cavity 65 to spread over the entire area in the cavity 65. Can be done. Cavity 65
It is preferable that the supply direction of the resin with respect to the direction in which the protrusions 64 extend as shown by an arrow Na in FIG. 6, for example. By doing so, it is possible to prevent the flow of the resin from being largely hindered by the convex portions 64.

After the production of the resin molded product 1 ', a coating treatment is performed. This coating process is performed, for example, by immersing the resin molded product 1 'in a black coating liquid 15', as shown in FIG. In this manner, the entire outer surface of the resin molded product 1 ', including the bottom surface and the side wall surface of each groove 14 of the resin molded product 1', is covered with the black coating film as a light shielding material. Thereafter, as shown in FIG. 8, a process of removing portions of the light shielding material 15 covering the resin molded product 1 ', which are attached to the lens surfaces 11a and 11b, is performed. This process is performed by wiping off the light shielding material 15 using a roller 80 made of a water absorbing member, for example, before the light shielding material 15 is dried and hardened. Of course, instead of the roller 80,
The light-blocking material 15 can be wiped off using a sponge-like or felt-like member of other forms. Since there is a step of dimension Lb between the peripheral edge of each lens surface 11a, 11b and the peripheral surface of each lens 11,
The light-shielding members 15 a and 11 b can be appropriately removed while being distinguished from the peripheral surface of each lens 11. Lens surface 11
a between the a and between the lens surfaces 11b.
Since the opening 4 is provided, the light shielding material 15 on the lens surfaces 11a and 11b can be more easily wiped off. By such a series of operations, as shown in FIG. 9, each lens surface 11a, 11
A resin molded product 1 'in which the region excluding b is covered with the light shielding material 15 made of a black coating film is obtained.

Next, as shown in FIG. 10, a cutting operation of the resin molded product 1 'is performed. This cutting operation is performed by the reference numerals Nb-Nb in FIG.
The resin molded product 1 'may be cut sequentially or simultaneously along the imaginary line. As the cutting means, various means such as mechanical processing using a cutter and laser processing can be adopted. By the above cutting operation, a plurality of elongated block-shaped lens arrays 1 are obtained. As shown in FIG. 11, each lens array 1 is composed of a plurality of lenses 11 arranged in a row so as to sandwich a plurality of concave grooves 14. The longitudinal cross-sectional shape is shown in FIG. It is the same as the cross-sectional shape. In addition, the side surface parts 1f and 1g which became the cut end surfaces are not covered with the light shielding material. Therefore, if necessary, these side portions 1f, 1g are thereafter formed.
Should be painted black.

According to the above-described manufacturing method, since a plurality of lens arrays 1 can be obtained from one resin molded product 1 ', the production efficiency of the lens array 1 is improved. In particular, in the intermediate processing (such as coating processing) until the resin molded product 1 ′ is divided into the plurality of lens arrays 1, the processing corresponding to the plurality of lens arrays 1 can be performed collectively, so that the production efficiency is increased. Will be further enhanced.

Next, one row of the plurality of lens arrays 1 manufactured by the above method will be described.

The above-described plurality of lens arrays 1 correspond to FIG.
As shown in (1), by combining two lens arrays 1A (1) and 1B (1) selected from them, it is used to construct a lens array assembly A. The lens array assembly A can obtain an erect equal-magnification image as described later.

The lens array assembly A includes the concave portions 13 of the lens array 1A and the convex portions 12 of the lens array 1B.
Are fitted to each other so that the two lens arrays 1A, 1
B are stacked, and the optical axes C of the plurality of lenses 11 are aligned. The two lens arrays 1A and 1B are manufactured from the same resin molded product 1 ', and the resin molding is performed under the same or substantially the same conditions using the same mold. The lenses 11 can be manufactured so as to eliminate the displacement between the lenses 11 corresponding to each other, and the optical axes C of the lenses 11 can be accurately aligned with each other.

In the above-described lens array assembly A, as shown in FIG. 13, light starting from the starting point S passes through the lens 11 of the lens array 1A and then passes through the lens 11 of the lens array 1B. The image point R is reached. In this case, the two lenses 11 as convex lenses arranged on the common optical axis C provide a phenomenon equivalent to the meandering phenomenon of light observed in the selfoc lens, and the object (a → b → c) at the starting point S Erect 1: 1 image (a '→ b' → c ')
Can be formed at the imaging point R. In other words, in the optical system shown in FIG.
A lens surface 11a is the lens surface 1a of the lens array 1A.
1b and a lens surface 11a of the lens array 1B, and plays a role of forming an inverted reduced image of the object (a → b → c), and the inverted reduced image is formed by a plurality of convex lens surfaces located downstream of the inverted reduced image. As a result of being enlarged and inverted,
An erect equal-size image of the object is formed at the image forming point R.

Therefore, the above-described lens array assembly A is suitable for use in forming an erect equal-magnification image of a document on a linear light-receiving element, for example, in a contact type sensor or another line image sensor. Further, since the lens array assembly A is an elongated one in which the narrow block-shaped lens arrays 1A and 1B are stacked, it is preferable in terms of space efficiency.

In the lens array assembly A, the light that has traveled from the starting point S toward the lens array 1A enters the lens 11 from a region other than the lens surface 11a. Is appropriately prevented by the light shielding material 15. Further, the light entering the lens 11 of the lens array 1A may enter the lens 11 adjacent to the lens 11 or the lens 11 adjacent to the lens 11 in the lens array 1B. Is prevented by As described above, the light shielding material 15 of the concave groove 14 is
1. It has the function of optically separating the two. Therefore, light crosstalk between the plurality of lenses 11 can be effectively prevented, and a clear erect equal-magnification image can be obtained.

Since the plurality of grooves 14 of the lens array 1A and the light shielding material 15 on the inner surface thereof are formed on both the front and back surfaces of the lens array 1A, the depth of each of the grooves 14 is relatively small. Also, a sufficient crosstalk prevention effect can be obtained. If the depth of each concave groove 14 can be reduced in this way, the projecting dimension of each convex portion 64 of the molds 6a and 6b used for resin molding of each concave groove 14 can be reduced accordingly. Therefore, the manufacture of the mold becomes easy, which is advantageous for forming the concave groove 14 to have a narrow width. Groove 1
If the width of the lens 4 can be reduced, the pitch of the lens 11 in the column direction can be reduced and the density of the lens 11 can be increased, which is advantageous for brightening an erect equal-magnification image.
In addition, since large-sized convex portions can be prevented from being present in the cavities 65 of the molds 6a and 6b, the flow of the resin in the cavities 65 becomes smooth, and furthermore, the deep concaves are formed in the resin molded product. Compared to the case where grooves are formed, it is possible to suppress the occurrence of residual stress when molding a resin molded product, and for example, it is possible to make the resin molded product less likely to be warped when the mold is opened. It becomes possible.

FIG. 14 is a sectional view showing another example of a lens array manufactured according to the present invention. FIG.
In the following drawings, the same or similar elements as those of the above embodiment are denoted by the same reference numerals as those of the above embodiment.

The two lens arrays 1C and 1 shown in FIG.
D constitutes a lens array assembly Aa capable of obtaining an erect equal-magnification image of the object. The lens array 1C is provided with a concave groove 14 located between the plurality of lenses 11 only on the surface (upper surface) side thereof, and a flat portion 19 between the lens surfaces 11b has a light shielding material 1
5 are provided. On the other hand, the lens array 1D
Has a configuration in which the concave groove 14 and the light shielding material 15 are not provided at all. The lens surface 11e of each lens 11 of the lens array 1D has a diameter equal to or larger than the lens surface 11b of the lens array 1C, and the lens surface 11f has a larger diameter than the lens surface 11e. The lens surfaces 11f are connected to each other. Of course, each of the lens arrays 1C and 1D is formed by dividing a substantially plate-shaped or substantially sheet-shaped resin molded product formed in a form in which a plurality of them are integrally connected.

By the combination of the lens arrays 1C and 1D, as shown in FIG. 15, an erect equal-magnification image (a ′ → b ′ → c ′) of the object (a → b → c) at the starting point S is obtained. Can be formed at the imaging point R. Although the concave groove 14 is provided only on the light incident side of the lens array 1C, the concave groove 14 is provided in the lens array 1 (1A) of the previous embodiment.
By forming the groove deeper than the concave groove 14, light crosstalk between the plurality of lenses 11 can be appropriately prevented. The lens array 1D is not provided with the concave groove 14 or the light shielding material 15, but light that may cause crosstalk in the lens array 1D is prevented from traveling from the lens array 1C toward the lens array 1D. It has been confirmed that the crosstalk can be prevented between the plurality of lenses 11 of the lens array 1D. Further, the lens array 1C,
In 1D, since the lens surface from which light is emitted has a larger diameter than the lens surface onto which light is incident, light incident on the lens 11a is guided from the final lens surface 11f to the image forming point R without waste. And the image formed can be made brighter.

As understood from the lens arrays 1C and 1D described above, the lens array manufactured by the manufacturing method of the present invention has a structure in which a concave groove for preventing crosstalk is formed only on one side of the front and back surfaces. Needless to say, it is also possible to adopt a configuration in which no concave groove is formed and no light shielding material is provided. Further, when forming a concave groove in the lens array, instead of means for forming the concave groove by a resin molding process, for example, after molding a resin molded product, by machining using a tool such as an end mill, or It may be formed by laser processing using an excimer laser, a pulsed carbon dioxide laser, or the like.

FIG. 16 is a plan view showing another example of the method for manufacturing a lens array according to the present invention.

In the manufacturing method shown in the figure, when dividing the resin molded product 1 ″ into a plurality of lens arrays 1E, the number of rows of the lenses 11 of each lens array 1E is set to a plurality of rows, for example, two rows. In the resin molding stage, the resin molded product 1 ″
The two lens rows are formed so as to approach each other in pairs. According to the lens array 1E manufactured by the above method, the same image can be formed by each of the two lenses 11 arranged in a direction intersecting with the column direction of the lenses.
The advantage that the formed image can be made brighter than the case where are provided in one line is obtained. Thus, in the present invention, the number of rows of lenses of the finally obtained lens array may be plural.

Of course, the scope of the present invention is not limited to the above embodiment. The lens array obtained by the present invention can be used for forming an inverted reduced image of an object by using the lens array alone, for example, like a conventional convex lens array. Also,
In the present invention, each lens of the lens array may be formed as a biconvex lens instead of a biconvex lens, and may be formed as a biconcave lens or a monoconcave lens. By using a concave lens array in combination with a convex lens array, it can be suitably used to eliminate chromatic aberration.

[Brief description of the drawings]

FIG. 1A is a plan view showing an example of a resin molded product as an intermediate product of a lens array, and FIG.
It is I sectional drawing.

FIG. 2 is a sectional perspective view of a main part of the resin molded product shown in FIG.

FIG. 3 is an enlarged sectional view of a main part of the resin molded product shown in FIG.

FIG. 4 is a sectional view showing a molding step of the resin molded article shown in FIGS. 1 to 3;

FIG. 5 is a sectional view showing a molding step of the resin molded article shown in FIGS. 1 to 3;

FIG. 6 is a sectional perspective view of a main part showing an example of a mold used for resin molding.

FIG. 7 is a cross-sectional view showing a step of performing a coating process on a resin molded product.

FIG. 8 is a cross-sectional view showing a step of removing a part of the coating of the resin molded product.

FIG. 9 is a cross-sectional view showing a state in which a step of removing a part of the coating of the resin molded product has been completed.

FIG. 10 is a plan view showing a step of dividing a resin molded product into a plurality of lens arrays.

FIG. 11 is a perspective view of an essential part showing an example of a manufactured lens array.

FIG. 12 is a sectional view showing an example of use of the manufactured lens array.

FIG. 13 is an operation explanatory view.

FIG. 14 is a sectional view showing another example of the lens array manufactured according to the present invention.

FIG. 15 is an operation explanatory view.

FIG. 16 is a plan view showing another example of the method for manufacturing a lens array according to the present invention.

FIG. 17 is a perspective view showing an example of a conventional lens array.

FIG. 18 is a sectional view of a main part of the lens array shown in FIG. 17;

[Explanation of symbols]

 1, 1A to 1E Lens array 1 ', 1 "Resin molded product 11 Lens 11a, 11b Lens surface (light input / output surface) 11c, 11d Outer peripheral surface 11e, 11f Lens surface (light input / output surface) 14 concave Groove 15 Light shielding material

Claims (8)

[Claims] 1. A resin molding step of molding a resin molded product in which a plurality of lenses having a convex or concave light input / output surface are arranged in a plurality of rows and are integrally connected, using a synthetic resin having a light transmitting property. And a dividing step of dividing the resin molded product into a plurality of lens arrays in which a plurality of lenses are arranged in a row. A method of manufacturing a lens array, comprising: 2. The method for manufacturing a lens array according to claim 1, wherein at least one side edge of the outer periphery of the resin molded product is thicker than a portion where a plurality of lenses are arranged in a row. 3. The resin molded article includes a concave groove that blocks between adjacent lenses in a row direction of the lenses.
A method for manufacturing the lens array according to claim 1. 4. The method for manufacturing a lens array according to claim 3, wherein the concave groove is provided on each of a front surface and a rear surface of the resin molded product. 5. A covering step of covering the whole or a part of a region of the resin molded product except for a light incident / exit surface of each lens of the resin molded product with a black or near-dark type light shielding material prior to the dividing step. The method for manufacturing a lens array according to claim 1, comprising: 6. The coating step comprises applying a black or near dark paint to the entire surface or substantially the entire surface of the resin molded product, and then drying the paint applied to the light input / output surface of each lens. It is a process to remove this before curing,
A method for manufacturing the lens array according to claim 5. 7. The method for manufacturing a lens array according to claim 1, wherein each lens of the resin molded article has an outer peripheral surface rising from a peripheral portion of each lens. 8. A lens array manufactured by the method for manufacturing a lens array according to claim 1.