JP2006030722A - Lens array for optical reading and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lens array for optical reading 1 which can control the effect of stray light and is easily manufactured. <P>SOLUTION: The lens array for optical reading 1 is constituted of a block-shaped lens array body 10 on whose upper and lower surfaces a plurality of lens elements 11 and 12 are arrayed in a line, and a partition part 20 integrally provided on a middle part 17 in the up-and-down direction of the lens array body 10, wherein the partition part 20 is formed of light absorptive resin material. The lens array body 10 is equipped with a plurality of cylindrical optical openings 13 fit to the arrays of the lens elements 11 and 12 at the middle part 17, and the peripheral surfaces of the respective optical openings 13 are covered with the partition part 20, and the optical openings 13 and 13 have ribs 14 projecting over their almost entire length in a longitudinal direction in a direction almost orthogonal to the arraying directions of the lens elements 11 and 12 from the peripheral surfaces. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an optical reading lens array in which a plurality of lens elements are arranged in a row, and more specifically, a light-shielding portion and an optical element inside a block-shaped lens array body in which a plurality of lens elements are arranged in a row on the upper and lower surfaces. The present invention relates to an optical reading lens array having an opening.

Currently, in a facsimile, a scanner, a copying machine, and the like, a lens array is used as an optical component for forming an image to be read. This lens array is an optical component in which lens elements are arranged in a line so that a one-dimensional erecting real image is obtained as a whole.
As a method of manufacturing this lens array, for example, as described in Patent Document 1 and Patent Document 2, first, a plurality of lens elements made of a gradient index glass rod are formed, and this lens element is used as a holding frame. There is a method in which the lens elements are arranged in a row on the frame plate, the lens elements are sandwiched by another frame plate from the opposite side, and a resin is injected into the gap between the lens elements to be coupled and integrated.
JP-A-6-347608 JP-A-6-59101

  By the way, in such a conventional manufacturing method, since the lens element and the holding frame are separately formed and integrated later, the manufacturing process of the lens array and the configuration of the lens array become complicated, and the manufacturing cost increases. . In view of this, a method of manufacturing a lens array by integrally molding a portion constituting the lens and other portions with a transparent optical resin has been considered. Specifically, this is a method in which a lens array having convex lens surfaces bulging vertically is integrally formed on the upper and lower surfaces of a block-shaped lens array body by injection molding. With this method, the lens array can be formed in one step by injection molding using a mold, so the manufacturing process and the configuration of the lens array are simplified, and the manufacturing cost can be reduced.

  However, if the part that constitutes the lens and the other part are integrally molded in this way, the lens part and the other part are molded from the same optical resin, so that unnecessary light is transmitted or reflected as it is. However, there has been a problem of stray light entering the light receiving portion together with the light imaged by the lens portion. As described above, when stray light enters the light receiving unit together with light that should be incident, an image formed by the lens portion is blurred and an appropriate image cannot be obtained.

  In order to suppress the influence of stray light, it is necessary to provide an appropriate light-shielding part and optical aperture in the middle of the lens array body. In this case, the optical aperture has a small diameter. At the time of molding, the optical aperture was not sufficiently filled with the optical resin, and it was difficult to form a lens array body having the optical aperture.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an optical reading lens array which can suppress the influence of stray light and can be easily manufactured.

In order to solve the above problems, an optical reading lens array according to the present invention is integrated with a block-shaped lens array body in which a plurality of lens elements are arranged in a row on the upper and lower surfaces, and an intermediate portion in the vertical direction of the lens array body. A partition wall portion, and the partition wall portion is an optical reading lens array formed of a light-absorbing resin material,
The lens array body includes a plurality of columnar optical apertures that match the arrangement of the lens elements in the intermediate portion, and each optical aperture is covered with the partition wall and has a circumferential surface covered with the lens elements. Each of the ribs has a rib projecting over the entire length in the longitudinal direction in a direction substantially orthogonal to the arrangement direction.

  In order to solve the above problems, the optical reading lens array according to the present invention is characterized in that the ribs are provided in two directions substantially orthogonal to the arrangement direction of the lens elements from the peripheral surface of each optical aperture. Has been.

  Furthermore, in order to solve the above-described problems, the optical reading lens array according to the present invention is such that the surface of the partition wall covering the peripheral surface of each optical aperture is light-scattered so that light incident on each optical aperture is not specularly reflected. It is configured to be a surface.

  Furthermore, in order to solve the above-described problem, the lens array for optical reading according to the present invention has a plurality of groove portions on the upper surface of the lens array main body, and the groove portions provide an optical path of light incident on the upper surface of the lens element. It is characterized by having an inclined surface that is refracted in a direction away from the optical axis.

  In order to solve the above problems, the optical reading lens array according to the present invention is characterized in that the inclined surface of each groove is formed in an inwardly inclined shape.

Furthermore, an optical reading lens array according to the present invention includes a block-shaped lens array body in which a plurality of lens elements are arranged in a row on the upper and lower surfaces, and a light-absorbing lens provided in an intermediate portion in the vertical direction of the lens array body. A method of manufacturing a lens array for optical reading, in which a partition wall made of a resin material is integrally formed with a mold,
Forming a lens element surface molding portion for forming upper and lower surfaces of a lens array body in which the lens elements are arranged in the mold;
A plurality of optical aperture molding portions that form cylindrical optical apertures that match the arrangement of the lens elements are formed in an intermediate portion in the vertical direction of the mold, and the peripheral surface of the optical aperture is formed with respect to the optical aperture molding portions. A step of further forming a rib forming portion for forming a rib protruding substantially over the entire length in the longitudinal direction in a direction substantially perpendicular to the arrangement direction of the lens elements;
Filling the mold in which the lens element surface molding part and the optical aperture molding part are formed with a translucent resin material and curing the mold to form the lens array body;
A space formed in the middle of the lens array body in the vertical direction corresponding to the optical aperture molding part and the rib molding part is filled with a light-absorbing resin material, and the partition part is integrated with the lens array body. And a step of forming them automatically.

  Furthermore, in the optical reading lens array according to the present invention, optical aperture mold members having the optical aperture molding part and the rib molding part are formed on the inner wall surfaces facing each other in the middle part in the vertical direction of the mold. The optical aperture molding member and the rib molding portion are formed such that the optical aperture mold member can protrude from the inner wall surface to a position where the optical aperture mold members are joined to each other.

  In the optical reading lens array according to the present invention, the optical aperture mold members formed on the inner wall surfaces facing each other of the mold in which the lens element surface molding portion and the optical aperture molding portion are formed are joined to each other. The lens array body is placed at a position away from the position, filled with a translucent resin material, and protrudes to a position where the optical aperture mold members are joined to each other before the translucent resin material is cured. It is configured to form.

  According to the lens array for optical reading according to the present invention, the lens array main body includes a plurality of columnar optical apertures that match the arrangement of the lens elements in the intermediate portion, and each optical aperture is covered with the partition wall at the peripheral surface, Since it has ribs that project over the entire length in the longitudinal direction in a direction substantially orthogonal to the arrangement direction of the lens elements from the peripheral surface, it becomes easier to fill each optical aperture with a resin material in the formation of the lens array body, Since the lens array main body can be easily formed, manufacturing by integrally forming the lens array main body and the partition wall is facilitated.

  Further, according to the optical reading lens array of the present invention, since the ribs are provided in two directions substantially orthogonal to the arrangement direction of the lens elements from the peripheral surface of each optical opening, the resin material is more reliably filled into the optical opening. Can be.

  Further, according to the optical reading lens array according to the present invention, the surface of the partition wall covering the peripheral surface of each optical aperture is a light scattering surface so that the light incident on each optical aperture is not specularly reflected. The light incident on the interface between the opening and the partition wall can be absorbed by the partition wall, and the influence of stray light can be further reduced.

  Furthermore, according to the optical reading lens array of the present invention, the upper surface of the lens array body has a plurality of grooves, and the grooves refract the optical path of light incident on the upper surface away from the optical axis of the lens element. Since it has an inclined surface, light incident on a position other than the lens element on the upper surface of the lens array body can be absorbed by the partition wall, and the influence of stray light can be further reduced.

  In addition, according to the optical reading lens array of the present invention, the slopes of the groove portions on the upper surface of the lens array body are formed in an inwardly inclined shape, so that the optical path of light incident on the upper surface is made planar. Compared to the case, the distance from the optical axis of the lens element can be increased, and the light incident on the upper surface can be absorbed by the partition wall, and the influence of stray light can be further reduced.

  Furthermore, according to the method for manufacturing an optical reading lens array according to the present invention, an optical aperture mold member having an optical aperture molding portion and a rib molding portion at an intermediate portion in the vertical direction of the mold is disposed on the inner wall surfaces facing each other. By forming the optical aperture mold member and the rib molded portion so that the optical aperture mold member can protrude from the inner wall surface to the position where it is joined to each other, the optical aperture molded portion and the rib molded portion can be easily formed. The manufacturing cost of the mold can be reduced.

  Further, according to the method of manufacturing an optical reading lens array according to the present invention, each optical aperture mold member is disposed at a position away from a position where the optical aperture mold members are joined to each other, and is filled with a translucent resin material. Since the resin material is filled also from the space formed between the aperture molding portions, the filling into each optical aperture molding portion becomes more reliable, and the lens array body can be easily formed.

  Embodiments of the present invention will be described in detail with reference to the drawings. 1 is a perspective view of an optical reading unit using the optical reading lens array in the embodiment of the present invention, FIG. 2 is a top view of the optical reading lens array in the embodiment of the present invention, and FIG. A sectional view, FIG. 4 is a sectional view taken along line BB in FIG. 2, and FIG. 5 is a sectional view taken along line CC in FIG. As shown in these drawings, the optical reading lens array 1 according to the present embodiment is used for various optical reading devices such as a facsimile, a scanner, and a copying machine, and is provided above the line sensor 2 in the optical reading device. It is provided and serves to form an image of the upper reading medium 3 on the lower line sensor 2 as an erecting equal-magnification real image. The optical reading lens array 1 includes a lens array body 10 that functions as a lens, and a partition wall 20 that is provided integrally with an intermediate portion 17 in the vertical direction of the lens array body 10.

  As shown in FIGS. 2 and 3, the lens array body 10 is formed in a long and substantially block shape, and includes a plurality of lens elements 11 and 12 arranged in a line at regular intervals on the upper and lower surfaces. Have. The lens elements 11 and 12 are formed to have a one-to-one correspondence on the upper and lower surfaces, and the pair of lens elements 11 and 12 and the lens array body 10 therebetween serve as one lens body. These lens elements 11 and 12 are formed on a bent surface that bulges upward or downward from the upper surface or lower surface of the lens array body 10 to form a convex lens surface. The upper lens element 11 is a light incident surface, whereas the lower lens element 12 is a light emitting surface, and light incident on the upper lens element 11 is emitted from the corresponding lower lens element 12. The image is formed on the line sensor 2 as an erecting equal-magnification real image. Each lens element 11, 12 may be either spherical or aspherical. Such a lens array main body 10 is a resin material having translucency, and is specifically molded by PMMA (polymethyl methacrylate) or amorphous polyolefin resin.

  Further, as shown in FIG. 3, the lens array main body 10 has a plurality of columnar optical openings 13 in the intermediate portion 17 in the vertical direction. The optical apertures 13 are formed at the same pitch as the lens elements 11 and 12 so as to correspond to the arrangement of the lens elements 11 and 12, and the optical apertures 13 and 13 are arranged along the optical axis of the lens elements 11 and 12. It is formed to have a slightly smaller diameter than the lens elements 11 and 12. Therefore, light incident on the lens element 11 provided on the upper surface of the lens array body 10 can be emitted from the lower lens element 12 corresponding to the upper lens element 11 through the corresponding optical aperture 13.

  Moreover, as shown in FIG. 3, each optical opening 13 and 13 has the rib 14 which protrudes over the full length direction in the direction substantially orthogonal to the arrangement direction of the lens elements 11 and 12 from the surrounding surface, respectively. As shown in FIGS. 4 and 5, each rib 14, 14 is formed in a plate shape from the peripheral surface of each optical aperture 13, 13 and is configured integrally with each optical aperture 13, 13. , 13 and the same resin material. In the present embodiment, the ribs 14 are provided in two directions substantially orthogonal to the arrangement direction of the lens elements 11 and 12.

  Since each of the optical apertures 13 and 13 has a small diameter, it has been difficult to sufficiently fill the resin material in the conventional mold 30 formation. However, since each of the optical openings 13 in the present embodiment has the ribs 14, the optical resin can be reliably filled. Details of the method of manufacturing the optical reading lens array 1 in this embodiment will be described later.

  Further, since the rib 14 is formed integrally with the optical aperture 13 and is formed of the same resin material, a part of stray light in the vicinity of the optical aperture 13 is transmitted by the light incident on the lens array body 10. . However, since the influence of this stray light is very small compared to the stray light straddling between the lens elements, the ribs 14 can be provided without greatly affecting the optical characteristics.

  The partition wall 20 provided integrally with the intermediate portion 17 of the lens array body 10 is formed of black PPS (polyphenylene sulfide) or PBT (polybutylene terephthalate) filled with silica filler so as to have light absorption. . As shown in FIG. 5, the partition wall portion 20 is disposed so as to surround the optical apertures 13 and 13. Furthermore, since each optical opening 13 and 13 is formed in the middle vicinity in the thickness direction of the partition part 20, the peripheral surface of each optical opening 13 and 13 is covered with the partition part 20 over the whole surface. Here, the surface of the partition wall portion 20 that covers the peripheral surfaces of the optical apertures 13 and 13 is a light scattering surface so that light incident on the optical apertures 13 and 13 is not specularly reflected.

  FIG. 6 is a longitudinal sectional view of a reading unit using the optical reading lens array schematically showing a path of light incident on the optical reading lens array in the present embodiment. As shown in this figure, by arranging a plurality of optical apertures 13 that match the arrangement of the lens elements 11 and 12 in the intermediate portion 17 of the lens array body 10 where the partition wall portion 20 is disposed, An optical path from the lens element 11 to the lower lens element 12 is secured. Since the peripheral surfaces of the optical openings 13 and 13 are covered with the partition wall portion 20 made of a light-absorbing resin material, unnecessary light incident on the lens array body 10 can be absorbed by the partition wall portion 20 and stray light. The influence of can be suppressed.

  However, the partition wall portion 20 may be formed so as to surround not only the intermediate portion 17 of the lens array body 10 but also the entire side surface of the lens array body 10. Thereby, since the optical reading lens array 1 can further absorb unnecessary light incident from the outside by the partition wall portion 20, the influence of stray light can be further suppressed.

  FIG. 7 is an enlarged cross-sectional view of the upper part of FIG. As shown in this figure, in the lens array body 10 in which the lens elements 11 and 12 are arranged in a row, a plurality of grooves 15 and 15 are formed on the upper surface at regular intervals along the longitudinal direction of the lens array body 10. Has been. Each groove portion 15 is formed in a symmetrical shape with respect to the optical axis of the lens element 11, has an inwardly inclined slope 16, and has a serrated cross section continuously with each adjacent groove portion 15. Here, the groove portion 15 is formed along the longitudinal direction of the lens array body 10. However, the present invention is not limited to this, and the groove portion 15 is formed to have a certain angle with respect to the longitudinal direction of the lens array body 10. May be.

  In this way, by forming the groove portion 15 having the inwardly inclined slope 16 on the upper surface of the lens array body 10, light incident on the upper surface of the lens array body 10 moves away from the optical axes of the lens elements 11 and 12. Be refracted. That is, when the direction of light incident on the upper surface of the lens array body 10 from the outside is a direction approaching the optical axis of the lens elements 11 and 12 (L1 in FIG. 7), the light is incident on the inwardly inclined surface 16 of the upper surface. As a result, the incident angle of light becomes larger than when the upper surface is formed in a planar shape, and the refractive angle of light on the upper surface becomes larger. That is, the optical path of light is refracted in a direction away from the optical axes of the lens elements 11 and 12 as compared with the case where the upper surface is planar.

  Further, when the direction of light incident on the upper surface of the lens array body 10 from the outside is a direction away from the optical axis of the lens elements 11 and 12 (L2 in FIG. 7), the incident angle of light forms the upper surface in a planar shape. The refraction angle of the light on the upper surface becomes smaller than that in the case of the above. That is, also in this case, the optical path of the light is refracted in a direction away from the optical axes of the lens elements 11 and 12 as compared with the case where the upper surface is planar.

  For this reason, light incident from a position other than the lens elements 11 and 12 on the upper surface of the lens array body 10 is refracted in a direction away from the optical axis of the lens elements 11 and 12, and is not transmitted through the optical aperture 13, so that the partition wall It is absorbed by 20 and the influence of stray light can be further suppressed.

  A method for manufacturing the optical reading lens array 1 in the present embodiment will be described. In the optical reading lens array 1 according to the present embodiment, a lens array body 10 and a partition wall portion 20 provided at an intermediate portion in the vertical direction of the lens array body 10 are integrally formed by a mold 30.

 As shown in FIG. 8, the lens array main body 10 is formed by an injection molding method in which upper and lower molds 30 formed so as to correspond to the outer shape of the lens array body 10 are opposed to each other, molten material is injected into the space, and cooled and solidified. It is formed. Here, since the metal mold | die 30 needs the rigidity which does not deform | transform with the applied pressure at the time of inject | pouring material into the space part, generally steel materials are used. In addition, a copper alloy or an aluminum alloy may be used to increase the cooling efficiency.

  First, a lens element surface molding portion 31 that forms the upper and lower surfaces of the lens array body 10 in which the lens elements 11 and 12 are arranged on the mold 30 is formed. Next, a plurality of optical aperture forming portions 33 for forming the cylindrical optical apertures 13 that match the arrangement of the lens elements 11 and 12 are formed in the middle portion 35 in the vertical direction of the mold 30. And the rib shaping | molding part which forms the rib 14 which protrudes over the full length direction in the direction substantially orthogonal to the arrangement direction of the lens elements 11 and 12 from the surrounding surface of the optical opening 13 with respect to each optical aperture shaping | molding part 33,33 By further forming 34, the mold 30 for forming the lens array body 10 is formed.

  Here, FIG. 9 is a longitudinal sectional view in a direction orthogonal to the longitudinal direction of the mold 30 forming the optical reading lens array 1 in the present embodiment. In this embodiment, as shown in FIGS. Optical aperture mold members 32 having an optical aperture molding portion 33 and a rib molding portion 34 are formed on the inner wall surfaces 36 of the mold 30 facing each other, respectively, in an intermediate portion 35 in the vertical direction of the mold 30. The optical aperture forming portion 33 and the rib forming portion 34 are formed so that the protrusion 32 can be protruded from the inner wall surface 36 of the mold 30 to a position where they are joined to each other.

  The optical aperture mold members 32 are each formed in a comb-teeth shape as shown in FIG. 10, arranged in the middle part 35 in the vertical direction of the mold 30, and joined to each other from the inner wall surface 36 of the mold 30. It can be protruded to the position. The optical aperture mold member 32 having the optical aperture molding part 33 and the rib molding part 34 is formed integrally with the mold 30, but can be manufactured separately from the mold 30. 33 and the rib forming part 34 can be easily formed, and the manufacturing cost of the entire mold 30 can be reduced.

  An optical aperture mold member 32 in which an optical aperture molding portion 33 is formed on a mold 30 in which a lens element surface molding portion 31 is formed is disposed in an intermediate portion 35 in the vertical direction of the mold 30 and protrudes to a position where they are joined to each other. Then, the lens array main body 10 can be formed by filling and curing a light-transmitting resin material. The translucent resin material is filled from one end of the lens array body 10 in the longitudinal direction due to the structure of the mold 30. Since the optical aperture 13 has a small diameter and is orthogonal to the flow direction of the resin material, the conventional optical aperture molding portion 33 is not sufficiently filled with the resin material, and it is difficult to form the lens array body 10. However, since the optical aperture molding portion 33 in this embodiment has the rib molding portion 34, the optical aperture molding portion 33 is filled with the resin material also from the rib molding portion 34, so that the resin material is surely filled. Can do. Thereby, the lens array body 10 can be easily formed.

  Further, the optical aperture mold members 32 are arranged at positions separated from the positions where the optical aperture mold members 32 are bonded to each other, filled with a resin material, and the optical aperture mold members 32 are projected to a position where they are bonded to each other immediately before the resin material is cured. The filling of the resin material into the opening molding portion 33 can be further ensured. Since the optical aperture mold member 32 is disposed at a position away from the position where the optical aperture mold members 32 are joined to each other, the resin material can be filled into the optical aperture molding portion 33 also from the space formed between the optical aperture molding portions 33. In addition, the resin material is pushed into the optical aperture molding portion 32 by projecting the optical aperture mold members 32 to a position where they are bonded to each other immediately before the resin material is cured, and the optical aperture molding portion 33 is further filled with the resin material. Can be sure.

  After curing the filled resin material, the lens array main body 10 can be formed by releasing the mold 30. After the lens array body 10 is formed, light is absorbed in the space formed corresponding to the optical aperture molding portion 33 and the rib molding portion 34 included in the optical aperture mold member 32 at the intermediate portion 17 in the vertical direction of the lens array body 10. By filling and curing a functional resin material, the partition wall 20 is formed in close contact with the space of the lens array body 10.

  Here, when the optical aperture mold member 32 is released, each of the optical apertures 13 and 13 has a small diameter, and thus has a problem such as breakage or deformation of the molded body. However, the formed optical openings 13 and 13 are reinforced by having the ribs 14 respectively, and can be prevented from being damaged or deformed.

  Although the embodiment of the present invention has been described above, the application of the present invention is not limited to this embodiment, and can be variously applied within the scope of the technical idea. For example, the shape of the rib 14 provided in the optical aperture 13 is not limited to the present embodiment as long as it can ensure sufficient filling of the resin material into the optical aperture 13, and may be any shape.

It is a perspective view of the optical reading part of the lens array for optical reading in this embodiment. It is a top view of the lens array for optical reading in this embodiment. It is AA sectional drawing of FIG. It is BB sectional drawing of FIG. It is CC sectional drawing of FIG. It is a longitudinal cross-sectional view of the reading part using the optical reading lens array which shows schematically the path | route of the light which injects into the optical reading lens array in this embodiment. FIG. 5 is a cross-sectional view illustrating an optical path of light incident on an upper surface in an enlarged view of an upper part of FIG. 4. It is a longitudinal cross-sectional view of the longitudinal direction of the metal mold | die which forms the lens array for optical reading in this embodiment. It is a longitudinal cross-sectional view of the direction orthogonal to the longitudinal direction of the metal mold | die which forms the lens array for optical reading in this embodiment, and is a (a, b) figure which shows a structure with an optical aperture mold member. It is a top view of an optical aperture mold member.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Optical reading lens array 2 Line sensor 3 Reading medium 10 Lens array main body 11, 12 Lens element 13 Optical opening 14 Rib 15 Groove part 16 Slope 17 Middle part 20 Bulkhead part 30 Mold 31 Lens element surface molding part 32 Optical opening metal mold | die Member 33 Optical aperture forming part 34 Rib forming part 35 Intermediate part 36 Inner wall surface

Claims (8)

It consists of a block-shaped lens array body in which a plurality of lens elements are arranged in a row on the upper and lower surfaces, and a partition wall portion that is integrally provided in an intermediate portion in the vertical direction of the lens array body. An optical reading lens array formed of a resin material of
The lens array body includes a plurality of columnar optical apertures that match the arrangement of the lens elements in the intermediate portion, and each optical aperture is covered with the partition wall and has a circumferential surface covered with the lens elements. An optical reading lens array, comprising ribs protruding over substantially the entire length in the longitudinal direction in a direction substantially perpendicular to the arrangement direction.   2. The lens array for optical reading according to claim 1, wherein the ribs are provided in two directions substantially perpendicular to the arrangement direction of the lens elements from the peripheral surface of each optical aperture.   3. The optical reading lens array according to claim 1, wherein the surface of the partition wall covering the peripheral surface of each optical aperture is a light scattering surface so that light incident on each optical aperture is not specularly reflected. .   The upper surface of the lens array body has a plurality of grooves, and the grooves have slopes that refract the optical path of light incident on the upper surface in a direction away from the optical axis of the lens element. The lens array for optical reading according to any one of the above.   5. The lens array for optical reading according to claim 4, wherein the slope of each groove is formed in an inwardly inclined shape. A block-shaped lens array main body in which a plurality of lens elements are arranged in a row on the upper and lower surfaces, and a partition wall portion made of a light-absorbing resin material provided in an intermediate portion in the vertical direction of the lens array main body are integrated by a mold A method of manufacturing an optical reading lens array formed in
Forming a lens element surface molding portion for forming upper and lower surfaces of a lens array body in which the lens elements are arranged in the mold;
A plurality of optical aperture molding portions for forming cylindrical optical apertures that match the arrangement of the lens elements are formed in an intermediate portion in the vertical direction of the mold, and the peripheral surface of the optical aperture is formed with respect to the optical aperture molding portions. Further forming a rib molding portion for forming a rib protruding substantially over the entire length in the longitudinal direction in a direction substantially orthogonal to the lens element arrangement direction;
Filling the mold in which the lens element surface molding part and the optical aperture molding part are formed with a translucent resin material and curing the mold to form the lens array body;
A space formed in the middle of the lens array body in the vertical direction corresponding to the optical aperture molding part and the rib molding part is filled with a light-absorbing resin material, and the partition part is integrated with the lens array body. Forming the optical reading lens array.   Optical aperture mold members having the optical aperture molding part and the rib molding part at the middle part in the vertical direction of the mold are respectively formed on mutually opposing inner wall surfaces, and the optical aperture mold member is 7. The method of manufacturing an optical reading lens array according to claim 6, wherein the optical aperture forming portion and the rib forming portion are formed so as to be freely projectable from the wall surface to a position where they are joined to each other.   The optical aperture mold member formed on the inner wall surfaces facing each other of the mold in which the lens element surface molding part and the optical aperture molding part are formed is disposed at a position away from the position where the lens element surface molding part and the optical aperture molding part are joined to each other. 8. The optical system according to claim 7, wherein the lens array body is formed by filling a resin material and projecting the optical aperture mold members to a position where they are joined to each other before the light-transmitting resin material is cured. Manufacturing method of reading lens array.

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