JP2013007970A - Imaging lens, lens array, imaging lens producing method, and imaging module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an imaging lens or the like that can be downsized, with respect to a wafer level lens.SOLUTION: The cross-sectional shape of an outer peripheral region 184 provided on the outer periphery of an effective area 183 of a wafer level lens 110, which is perpendicular to an optical axis 110c, is similar to the shape of a light receiving part 144R.

Description

  The present invention relates to an imaging lens manufactured by a wafer level lens process (hereinafter referred to as “wafer level lens”) and the like.

  Due to the increase in sales of smartphones and the spread of mobile phones in emerging countries, in recent years, the demand for camera modules for portable devices (mobile devices) has increased significantly. On the other hand, price competition is intensifying for the camera module.

  Under these circumstances, a manufacturing process called a wafer level lens process has been developed as a method for mass-producing an imaging lens mounted on the camera module at a low cost.

  The wafer level lens process is a process in which a lens array in which a plurality of lenses are arranged on the same surface of one wafer is divided for each lens (wafer level lens singulation). It is a manufacturing process. In particular, the wafer level lens process is a lens in which a plurality of lens arrays each having a plurality of lenses arranged on the same surface of one wafer are bonded together, and each lens array includes this (lens array unit). This is a process for manufacturing a wafer level lens composed of a plurality of lenses through a process of dividing each combination (single wafer wafer lens).

  Patent Documents 1 to 3 disclose a method for manufacturing a wafer level lens by a wafer level lens process.

JP 2011-64873 A (published March 31, 2011) JP 2011-62879 A (published March 31, 2011) JP 2011-43605 A (published March 3, 2011)

  In the wafer level lens process, normally, with respect to each lens array, the arrangement of a plurality of lenses arranged in an array is a square shape in which the arrangement of a plurality of lenses is arranged at a constant pitch in the vertical and horizontal directions as disclosed in the example of Patent Document 3. It becomes the matrix of. When a plurality of lens arrays bonded together are divided and separated into individual wafer level lenses, the outer shape of the wafer level lens is an effective area having a lens function (the outer shape is circular). In addition, it was generally a square or a circle including the surrounding area.

  Here, the outer shape of the wafer level lens means a cross-sectional shape of the wafer level lens that is perpendicular to the optical axis of the wafer level lens. The same applies to the outer shape of the effective area.

  A wafer level lens having a square or circular outer shape has a problem that it is large.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide an imaging lens that can be miniaturized in a wafer level lens, a lens array including a lens constituting the imaging lens, and the imaging A lens manufacturing method and an imaging module including the imaging lens are realized.

  In order to solve the above problems, the imaging lens of the present invention is an imaging lens manufactured by cutting out one of the lenses from a lens array in which a plurality of lenses are arranged on the same surface of the wafer. The shape of the cross section perpendicular to the optical axis of the imaging lens in the outer peripheral area provided on the outer periphery of the effective area of the imaging lens is similar to the shape of the light receiving unit on which the imaging lens collects light. It is characterized by its shape.

  In addition, in order to solve the above-described problem, the imaging lens manufacturing method of the present invention is manufactured by cutting out one of the lenses from a lens array in which a plurality of lenses are arranged on the same surface of the wafer. An imaging lens manufacturing method according to claim 1, wherein a shape of a cross section perpendicular to an optical axis of the imaging lens in an outer peripheral area provided on an outer periphery of an effective area of the imaging lens is such that the imaging lens collects light. It is characterized by including a step of cutting out from the lens array so as to be similar to the shape of the light receiving portion that emits light.

  According to the above configuration, the wafer level lens can be reduced in size.

  That is, consider a case where a camera module is configured by combining an imaging lens and an imaging element, for example.

  The aspect ratio (ratio between the vertical dimension and the horizontal dimension) of the light receiving portion of the image sensor is usually 3: 4 or 9:16. That is, the light receiving part of the image sensor is generally rectangular. Therefore, if the shape of the cross section of the imaging lens (the outer shape of the imaging lens) perpendicular to the optical axis of the imaging lens is a square having the long side of the rectangle as the size of one side, imaging is performed. In the lens, an area unnecessary for the light receiving unit is generated in the direction of the short side of the rectangle. Conventionally, this unnecessary area has been a factor in increasing the size of the imaging lens.

  Usually, a lens is produced in rotational symmetry, and an image formed by the lens is circular, and this circle is expressed as, for example, an effective image circle. On the other hand, for example, the outer shape of the image sensor and the shape of the light receiving portion are generally quadrangular. Therefore, the portion of the effective image circle corresponding to the outside of the light receiving unit is unnecessary. Regarding the lens portion corresponding to this unnecessary portion, even if it is an effective region (also referred to as an optical effective region) that affects the effective image circle other than the portion necessary for the assembly configuration of the imaging lens, it is unnecessary.

  Therefore, according to the above configuration, it is possible to realize a wafer level lens having a reduced outer shape by deleting a part of the imaging lens corresponding to the unnecessary area.

  Moreover, it becomes possible to reduce the stray light component which penetrates into the light receiving unit by deleting the unnecessary area.

  Note that the light receiving unit may have a configuration in which the light receiving unit is a surface of the image sensor facing the imaging lens itself (its shape corresponds to the outer shape of the image sensor), in addition to the configuration of the image sensor. It may be the composition with which members other than are provided. Here, the outer shape of the image sensor means the shape of the cross section of the image sensor that is parallel to the cross section that defines the outer shape of the image lens in an imaging module including the imaging lens and the image sensor.

  In the imaging lens of the present invention, it is preferable that a plurality of similar lenses are bonded to each other adjacent to the direction of the optical axis.

  The imaging lens manufacturing method of the present invention includes a step of manufacturing a lens array unit by bonding the lens arrays adjacent to each other in the direction of the optical axis using a plurality of the lens arrays, and the lens array unit. And cutting out one lens for each lens array.

  According to said structure, size reduction is realizable in the wafer level lens provided with the some lens cut out from the lens array unit which bonded the some lens array.

  In the imaging lens of the present invention, the effective area may not be circular in a cross section perpendicular to the optical axis of the imaging lens.

  That is, even if the effective area of the lens whose cross section of the imaging lens is perpendicular to the optical axis of the imaging lens and whose effective area is circular (a general lens having rotational symmetry) is partially deleted, It is possible to realize the imaging lens of the present invention.

  In the lens array of the present invention, in a plan view of the lens array, a plurality of lenses having an effective area in which the vertical edges are arcuate and the horizontal edges are linear, the vertical and horizontal directions are Each of the plurality of lenses has a ratio of the vertical dimension to the horizontal dimension of 3: 4 or 9:16. The effective areas of the lenses constituting one row are arranged in a row.

  According to said structure, the lens which comprises one image among the imaging lenses of this invention which can reduce in size of an imaging lens can be arrange | positioned in one wafer. Therefore, since the number of lenses provided on one wafer can be increased, more imaging lenses can be manufactured in a short time.

  Moreover, the imaging module of this invention is equipped with the imaging lens of this invention, and the image pick-up element provided with the said light-receiving part, It is characterized by the above-mentioned.

  According to said structure, since an imaging lens can be reduced in size, an imaging module can be reduced in size.

  As described above, the imaging lens of the present invention is an imaging lens manufactured by cutting out one of the lenses from a lens array in which a plurality of lenses are arranged on the same surface of the wafer. The shape of the cross section perpendicular to the optical axis of the imaging lens in the outer peripheral area provided on the outer periphery of the effective area of the lens is similar to the shape of the light receiving portion on which the imaging lens collects light.

  The imaging lens manufacturing method of the present invention is a manufacturing method of an imaging lens manufactured by cutting out one of the lenses from a lens array in which a plurality of lenses are arranged on the same surface of a wafer. The shape of the cross section perpendicular to the optical axis of the imaging lens in the outer peripheral area provided on the outer periphery of the effective area of the imaging lens is similar to the shape of the light receiving unit that collects light by the imaging lens. And a step of cutting out from the lens array.

  Therefore, there is an effect that the imaging lens can be reduced in size.

  In the lens array of the present invention, in a plan view of the lens array, a plurality of lenses having an effective area in which the vertical edges are arcuate and the horizontal edges are linear, the vertical and horizontal directions are Each of the plurality of lenses has a ratio of the vertical dimension to the horizontal dimension of 3: 4 or 9:16. The effective areas of the lenses constituting one row are arranged in series.

  Therefore, it is possible to produce more imaging lenses in a short time.

1A to 1D are perspective views showing a method for manufacturing an imaging lens of the present invention. In particular, FIG. 1D is a perspective view showing a configuration of the imaging lens of the present invention. FIG. 2A is a plan view showing the arrangement of a plurality of lenses in the lens array according to the prior art, and FIG. 2B is a perspective view showing the configuration of the imaging lens according to the prior art. It is a top view which shows arrangement | positioning of several lenses in the lens array which concerns on this invention. It is sectional drawing which shows an example of a structure of the camera module provided with the imaging lens shown in FIG.1 (d), and a top view which shows the structure of the imaging lens and imaging device corresponding to it.

[Arrangement of a plurality of lenses in a lens array according to the prior art]
FIG. 2A is a plan view showing the arrangement of a plurality of lenses in the lens array according to the prior art.

  A lens array 120 shown in FIG. 2A is provided with a plurality of lenses 122 on a wafer 121.

  The wafer 121 is made of, for example, a resin.

  The lens surface of the wafer 121 is molded on both surfaces thereof by transferring a lens surface (whether spherical or aspherical) using a mold. One lens 122 includes a lens surface formed on one surface of the wafer 121 and a lens surface formed on the other surface of the wafer 121, which are arranged to face each other on the wafer 121. It is provided.

  The lens 122 includes an effective area 123 having a function as a lens on each lens surface.

  Here, in the plan view of the lens array 120, the effective area 123 of each lens 122 is circular as shown in FIG. In other words, when one surface or the other surface of the wafer 121, which is the surface of the lens array 120 perpendicular to the optical axis (details will be described later) of the imaging lens, is shown as a plan view, The effective area 123 looks circular. That is, it can be said that the lens surface of each lens 122 shown in FIG. 2A is rotationally symmetric.

  Here, in the lens array 120 shown in FIG. 2A, a plurality of lenses 122 are arranged on both surfaces of the wafer 121 so as to form a square matrix in which the lenses 122 are arranged at a constant pitch in the vertical and horizontal directions. Yes.

  That is, the plurality of lenses 122 constitute a plurality of lens rows (horizontal) 124a to 124e that are parallel to each other, and are arranged to constitute a plurality of lens rows (vertical) 125a to 125e that are parallel to each other. Yes.

  Further, the pitches of any two adjacent lenses 122 in the lens array (horizontal) 124a are all equal. The same applies to the lens rows (horizontal) 124b to 124e. In addition, the pitches of any two adjacent lenses 122 in the lens array (vertical) 125a are all equal. The same applies to the lens rows (vertical) 125b to 125e. When the pitch in the lens array (horizontal) 124a and the pitch in the lens array (vertical) 125a are compared, they have a right angle relationship, but the absolute value of the distance is the same. The same applies when the pitch in each lens array (horizontal) 124b to 124e is compared with the pitch in each corresponding lens array (vertical) 125b to 125e.

  FIG. 2A shows a configuration in which the lens array 120 further includes one lens 122 on each side of the lens array (horizontal) 124c and both sides of the lens array (vertical) 125c. Show.

  The lens array 120 is cut at a cutting edge 126 shown in FIG. Accordingly, the plurality of lenses 122 included in the lens array 120 are cut for each lens 122.

  Here, when a plurality of lenses 122 constituting the matrix are cut out from the lens array 120, particularly when a plurality of lenses 122 are cut out from the lens array 120 in a lump, the cutting margins 126 have a lattice shape in plan view. Preferably there is. Specifically, it is preferable that the margin 126 is determined in such a manner that one lens 122 is positioned in one of the areas that are in a lattice shape and have a gap in the lattice.

  By making the cutting edge 126 into a lattice shape as described above, the cutting edge 126 is configured only by a straight line extending either vertically or horizontally. As a result, when the lens 122 is cut out, it is not necessary to meander a device for cutting (not shown in FIG. 2A), so that a plurality of lenses 122 are cut out, that is, the lenses 122 are separated into individual pieces. Becomes easy.

  In addition, it is conceivable that the cutting edge 126 has a circular shape provided so as to surround each lens 122, but in this case, the cutting edge 126 meanders and it is difficult to separate the lens 122 into individual pieces.

[Configuration of Imaging Lens According to Prior Art]
FIG. 2B is a perspective view illustrating a configuration of an imaging lens according to the related art.

  It is possible to manufacture a wafer level lens composed of a plurality of lenses by bonding a plurality of lens arrays and dividing this (lens array unit) for each combination of lenses included in each lens array. .

  That is, the wafer level lens 127 shown in FIG. 2B is manufactured by three lens arrays, that is, the lens array 120, the lens array 120A, and the lens array 120B. The lens array 120A and the lens array 120B are lens arrays having the same configuration as the lens array 120 except for the shape of each lens surface, and are not shown for convenience.

  The wafer level lens 127 is composed of three types of three lenses: a lens 122 included in the lens array 120, a lens 122A included in the lens array 120A, and a lens 122B included in the lens array 120B.

  The procedure for manufacturing the wafer level lens 127 by the wafer level lens process is, for example, as follows.

  First, the lens array 120 and the lens array 120A are bonded together. At this time, the lens array 120 and the lens array 120A are arranged so that the plurality of lenses 122 included in the lens array 120 and the plurality of lenses 122A included in the lens array 120A are opposed to each other in a one-to-one correspondence relationship. Are pasted together.

  Further, the lens array 120A bonded to the lens array 120 and the lens array 120B are bonded together. At this time, the lens array 120A and the lens array 120B are arranged such that the plurality of lenses 122A included in the lens array 120A and the plurality of lenses 122B included in the lens array 120B are opposed to each other in a one-to-one correspondence relationship. Are pasted together.

  The lens array 120, the lens array 120A, and the lens array 120B are bonded to each other, and one set of one lens 122, one lens 122A, and one lens 122B that are opposed to each other. Disconnect as. A pair of the cut lens 122, lens 122A, and lens 122B corresponds to each lens constituting the wafer level lens 127.

  Consider a case where the margin 126 for cutting the one set of the lens 122, the lens 122A, and the lens 122B has the above-described lattice shape. In this case, the wafer level lens 127 manufactured by being cut at the cutting edge 126 has a cross-sectional shape perpendicular to the optical axis 127c of the wafer level lens 127, that is, the outer shape has an effective region 123 (the outer shape is circular). ) And a square including the surrounding area.

  The wafer level lens 127 having a square outer shape has a larger size than an imaging lens manufactured by injection molding or the like, which causes a problem of being large.

  The above problem also occurs when a wafer level lens is manufactured by cutting one lens array 120 and using one lens 122. The above problem occurs similarly even if the outer shape of the wafer level lens is circular.

[Arrangement of a plurality of lenses in the lens array according to the embodiment]
FIG. 3 is a plan view showing the arrangement of a plurality of lenses in the lens array according to the present embodiment.

  A lens array 130 shown in FIG. 3 is formed by arranging a plurality of lenses 132 on the same surface of a wafer 131.

  The wafer 131 is made of, for example, a resin, and is preferably made of a thermosetting resin or an ultraviolet curable resin.

  The lens surface of the wafer 131 is molded on both surfaces by transferring a lens surface (whether spherical or aspherical) using a mold. One lens 132 includes a lens surface formed on one surface of the wafer 131 and a lens surface formed on the other surface of the wafer 131, which are arranged to face each other on the wafer 131. It is provided.

  The lens 132 includes an effective area 133 having a function as a lens on each lens surface. The effective area 133 has a different shape from the effective area 123 shown in FIG. 2A, which will be described later.

  Of the configuration of the lens array 130, the configuration described above is substantially the same as the configuration of the lens array 120.

  In the lens array 130 shown in FIG. 3, a plurality of lenses 132 are arranged on both surfaces of the wafer 131.

  Here, the arrangement of the plurality of lenses 132 on both surfaces of the wafer 131 is different from that of the lens array 120, that is, the arrangement of the plurality of lenses 122 on both surfaces of the wafer 121.

  Hereinafter, the arrangement of the plurality of lenses 132 on both surfaces of the wafer 131 will be described.

  First, the plurality of lenses 132 are arranged to form a plurality of lens rows (lateral) 134a to 134g that are parallel to each other. The plurality of lenses 132 are arranged so as to constitute a plurality of lens rows (vertical) 135a to 135g that are parallel to each other.

  The lens rows (horizontal) 134 a to 134 g and the lens rows (vertical) 135 a to 135 g extend in directions perpendicular to each other in a plan view of the lens array 130. Hereinafter, in the plan view of the lens array 130, the right and left direction of the paper surface, which is the extending direction of the lens rows (horizontal) 134a to 134g, is referred to as "lateral direction", and the paper surface is the extending direction of the lens rows (vertical) 135a to 135g. The vertical direction is referred to as “vertical direction”.

  Hereinafter, “vertical direction” and “lateral direction” mean two directions orthogonal to each other on the same plane.

  That is, in the present embodiment, any one direction is set to one of the vertical direction and the horizontal direction, and the direction perpendicular to the one direction is the vertical direction and the horizontal direction on a certain plane. The other. In FIG. 3, the horizontal direction of the paper surface is the horizontal direction, and the vertical direction of the paper surface perpendicular to the horizontal direction of the paper surface is the vertical direction on the plane of the lens array 130 corresponding to the paper surface of FIG.

  A plurality of (here, seven) lenses 132 constituting the lens array (horizontal) 134a are arranged at equal intervals, that is, so that the pitch between two lenses 132 adjacent in the horizontal direction is constant. Has been. The pitch here refers to a distance of a straight line connecting the center of one lens 132 and the center of the other lens 132 with respect to two adjacent lenses 132. The lens rows (horizontal) 134b to 134g are the same as the lens rows (horizontal) 134a.

  That is, the plurality of lenses 132 constituting one row among the lens rows (horizontal) 134a to 134g are arranged so that the pitch between any two lenses 132 adjacent in the horizontal direction is constant. .

  A plurality of (in this case, seven) lenses 132 constituting the lens array (vertical) 135a are arranged at equal intervals, that is, such that the pitch between two lenses 132 adjacent in the vertical direction is constant. Has been. The lens rows (vertical) 135b to 135g are the same as the lens rows (vertical) 135a.

  That is, the plurality of lenses 132 constituting one row among the lens rows (vertical) 135a to 135g are arranged so that the pitch between any two lenses 132 adjacent in the vertical direction is constant. .

  Here, each of the effective regions 133 in the plurality of lenses 132 has a bow shape in the vertical direction edge 138v in the plan view of the lens array 130, and a linear shape in the horizontal direction edge 138t. It has become. The linear shape referred to here is a shape in which the edge is not rounded and the cross section of the edge along the optical axis of the corresponding lens is a plane.

  In other words, each effective region 133 has a vertical edge 138t in a vertical direction in the original outer shape by providing a horizontal edge 138t from a circular original outer shape having all the vertical edges 138v as edges (circumference). It has an outer shape in which parts corresponding to both ends of the are deleted. In other words, each effective area 133 is formed by providing a lateral edge 138t from an original effective area that is a spherical surface or the like having all of the vertical edges 138v as edges (surfaces). A portion corresponding to both ends in the vertical direction in the region is deleted.

  Accordingly, each of the plurality of lenses 132 has an imaging element that is used when a ratio a: b between the vertical dimension aw and the horizontal dimension bw constitutes an imaging module including the lens 132. The aspect ratio of the light receiving unit (not shown) or the aspect ratio of the outer shape of the image sensor is typically set to a: b = 3: 4 or a: b = 9: 16. . Note that the letters a, b, and w indicating the dimensions are all positive numbers.

  Further, in each of the lens rows (vertical) 135a to 135g, a plurality of lenses 132 constituting the own row are integrated with each other at a horizontal edge 138t that is linear in the vertical direction. Accordingly, the plurality of lenses 132 constituting the row are arranged so as to be continuous in the vertical direction.

  In FIG. 3, the lens array 130 further includes one lens 132 on each side of each lens row (vertical) 135b and 135f, and each lens row (vertical) 135c to 135e. The configuration further includes two lenses 132 on each side on each side. These lenses 132 have the same configuration as the plurality of lenses 132 included in the lens rows (horizontal) 134a to 134g and the lens rows (vertical) 135a to 135g.

  The lens array 130 is cut at a cutting edge 136 shown in FIG. Accordingly, the plurality of lenses 132 included in the lens array 130 are cut for each lens 132.

  Here, when a plurality of lenses 132 are cut out from the lens array 130, particularly when a plurality of lenses 132 are cut out from the lens array 130 in a lump, the cutting margin 136 has a lattice shape in plan view of the lens array 130. . Specifically, the cutting margin 136 has a lattice shape, and is determined so that one lens 132 is positioned in one of the regions in the lattice.

  However, the margin 136 is determined so that the longitudinal dimension of each lens 132 is aw and the lateral dimension of each lens 132 is bw in a plan view of the lens array 130.

  Thereby, a large number of lenses 132 constituting one of the wafer level lenses can be arranged on one wafer 131. Therefore, since the number of lenses 132 provided on one wafer 131 can be increased, more wafer level lenses can be manufactured in a short time.

[Manufacturing Method and Configuration of Imaging Lens According to Embodiment]
1A to 1D are perspective views illustrating a method for manufacturing an imaging lens according to the present embodiment. In particular, FIG. 1D is a perspective view showing the configuration of the imaging lens according to the present embodiment.

  A wafer level lens (imaging lens) 110 shown in FIG. 1D is manufactured by a wafer level lens process. For this reason, mass production in a short time is possible, and manufacturing cost can be reduced. Further, the wafer level lens 110 may be one that can be reflowed as a result of each lens being made of a thermosetting resin or an ultraviolet curable resin.

  With reference to FIGS. 1A to 1D, a method of manufacturing the wafer level lens 110 by the wafer level lens process will be described.

  From here, the process shown to Fig.1 (a) is demonstrated.

  A wafer 181 made of a resin (preferably a thermosetting resin or an ultraviolet curable resin) is sandwiched between the upper mold 111a and the lower mold 111b, and the wafer 181 is heated and cured, and the wafer 181 is attached to the lens array 180. Mold.

  Here, the lens array 180 shown in FIG. 1A has a configuration close to that of the lens array 120 (see FIG. 2A), and the effective region 183 is circular in a plan view of the lens array 180. That is, the effective area 183 is not partially deleted from the original outer shape and is different from the lens array 130.

  However, the wafer level lens according to the present embodiment can be manufactured by the following wafer level lens process regardless of whether or not the effective area is deleted like the effective area 133. When the wafer level lens according to the present embodiment is realized, whether to use the lens array 180 shown in FIG. 1A or the lens array 130 shown in FIG. 3 is not particularly limited.

  The lens array 180 corresponds to the lens array 130, but the wafer 181 corresponds to the wafer 131, the lens 182 corresponds to the lens 132, the effective area 183 corresponds to the effective area 133, and the cut margin 186 is cut off. 136.

  Here, the mold top 111a has a shape opposite to the lens surface on the surface (transfer surface) sandwiching the wafer 181 so that a plurality of lens surfaces of the lens 182 can be formed on the wafer 181. A plurality of are formed.

  Similarly, a plurality of shapes opposite to the lens surface are formed on the surface sandwiching the wafer 181 so that the lower lens surface 111b can mold the other lens surface of the lens 182 to the wafer 181. ing.

  Each of the shapes opposite to the one lens surface of the lens 182 formed on the mold 111a and each of the shapes opposite to the other lens surface of the lens 182 formed on the bottom of the mold 111b When the wafer 181 is sandwiched between the upper mold 111a and the lower mold 111b, the wafers 181 are arranged so as to correspond one-to-one and the corresponding shapes face each other.

  A combination of lens surfaces facing each other formed in the lens array 180 is a single lens 182.

  Further, in the same manner as in this example, a wafer different from the wafer 181 is formed into a lens array different from the lens array 180 by a mold. Hereinafter, the lens array different from the lens array 180 is referred to as a lens array 180A. The lens array 180A is a lens array having the same configuration as the lens array 180 except for the shape of each lens surface.

  From here, the process shown in FIG.1 (b) is demonstrated.

  The lens array 180 and the lens array 180A obtained by molding in the process shown in FIG. The lens array 180 and the lens array 180A that are adjacent to each other in the direction of the optical axis 110c of the wafer level lens 110 are referred to as a lens array unit 112.

  At this time, the above bonding is performed so that the lens 182 formed in the lens array 180 and the corresponding lens 182A including the effective region 183A formed in the lens array 180A are arranged to face each other. Done. More preferably, each lens 182 formed in the lens array 180 adjacent to the direction of the optical axis 110c of the wafer level lens 110 and each lens 182A formed in the lens array 180A have a one-to-one correspondence. In addition, the above-described bonding is performed so as to face each other.

  More specifically, in the lens 182 and the lens 182A that are arranged to face each other, it is ideal that the optical axes of the lens 182 and the lens 182A are positioned on the same straight line after the above bonding.

  Note that the shape of the effective region 183A of the lens 182A is not particularly limited, and may be different for each lens surface of the lens 182A. Therefore, in FIG. 1B and FIG. 1D, the effective region 183A is illustrated with a dotted line for convenience of illustration. The same applies to the effective region 183 of the lens 182 that the shape of the effective region is not limited.

  From here, the process shown in FIG.1 (c) is demonstrated.

  The lens array unit 112 is cut by the cutting device 113.

  Here, the cutting device 113 performs the above-described cutting in units of the lens combination 114, which is one set of the lens 182 and the lens 182A that are in a facing arrangement. Further, the above-described cutting is performed at the margin 186 determined in the lens array 180 and the lens array 180A corresponding to the margin 136.

  The lens combination 114 after being cut by the cutting device 113 is shown in FIG.

  One lens combination 114 shown in FIG. 1D corresponds to the wafer level lens 110.

  The wafer level lens 110 manufactured by cutting at the cutting margin 186 has a cross section perpendicular to the optical axis 110c of the wafer level lens 110 (a cross section of the imaging lens perpendicular to the optical axis of the imaging lens). ), That is, the outer shape is as follows. However, since the cross section is a surface that defines the outer shape of the wafer level lens 110, the cross section of the outer peripheral region 184 corresponding to the outermost side of the lens 182 (the outer periphery of the effective region 183) and the outermost side of the lens 182A (the effective region 183A). The outer periphery of the outer peripheral region 184A. That is, the “cross section of the wafer level lens 110” referred to here is both the outer peripheral area 184 and the outer peripheral area 184A.

  That is, the lens 182 constituting the wafer level lens 110 is a center 144Rc of a light receiving unit 144R (see FIG. 4 corresponding to the light receiving unit of the image sensor or the outer shape of the image sensor) on which the wafer level lens 110 collects light. A part of the effective area 183c corresponding to is the center. The same applies to the lens 182A.

  Further, the cross-sectional shape of the wafer level lens 110 that is perpendicular to the optical axis 110c of the wafer level lens 110, that is, the outer shape of the wafer level lens 110 is the same as the aspect ratio of the light receiving unit 144R. That is, when the ratio of the vertical dimension to the horizontal dimension in the light receiving unit 144R is a: b, the wafer level lens 110 has a ratio of the vertical dimension to the horizontal dimension of a: b. Become. Here, the vertical dimension is az, and the horizontal dimension is bz. Note that the letter z indicating the dimension is a positive number.

  In other words, in the wafer level lens 110, the cross-sectional shape perpendicular to the optical axis 110c of the outer peripheral regions 184 and 184A provided on the outer periphery of the effective regions 183 and 183A is similar to the shape of the light receiving unit 144R. It is a shape.

  It should be noted that the wafer level lens according to the present embodiment only needs to have the above-described outer shape described for wafer level lens 110. On the other hand, the configuration itself such as the lens 132 of the lens array 130 that deletes the effective area is not an essential configuration in the wafer level lens according to the present embodiment. This is why the lens array 180 shown in FIG. 1A or the lens array 130 shown in FIG. 3 is not particularly limited when the wafer level lens according to the present embodiment is realized. I can say that.

  As a result, the wafer level lens can be miniaturized.

  That is, consider a case where a camera module is configured by combining, for example, a wafer level lens and an image sensor.

  The aspect ratio of the light receiving portion of the image sensor is usually 3: 4 or 9:16. That is, the light receiving part of the image sensor is generally rectangular. For this reason, the cross-sectional shape of the wafer level lens (outer shape of the wafer level lens) perpendicular to the optical axis of the wafer level lens is the dimension of the long side of the rectangle (the lateral dimension in the wafer level lens 110). ) As a dimension of one side, the wafer level lens generates an area unnecessary for the light receiving unit in the direction of the short side of the rectangle (vertical direction in the wafer level lens 110). Conventionally, this unnecessary area has been a factor in increasing the size of the wafer level lens.

  Accordingly, the shape of the cross section perpendicular to the optical axis 110c of the outer peripheral regions 184 and 184A is made similar to the shape of the light receiving portion 144R, and the wafer level lens portion corresponding to the unnecessary region is deleted. Thus, it is possible to realize the wafer level lens 110 whose outer shape is miniaturized.

  Moreover, it becomes possible to reduce the stray light component which penetrates into the light receiving unit by deleting the unnecessary area.

  Note that the light receiving unit may have a configuration in which the light receiving unit is a surface of the image sensor facing the imaging lens itself (its shape corresponds to the outer shape of the image sensor), in addition to the configuration of the image sensor. It may be the composition with which members other than are provided.

  Usually, a lens is produced in rotational symmetry, and an image formed by the lens is circular, and this circle is expressed as, for example, an effective image circle. On the other hand, for example, the outer shape of the image sensor and the shape of the light receiving portion are generally quadrangular. Therefore, the portion of the effective image circle corresponding to the outside of the light receiving unit is unnecessary. Regarding the lens portion corresponding to this unnecessary portion, even if it is an effective region (also referred to as an optical effective region) that affects the effective image circle other than the portion necessary for the assembly configuration of the imaging lens, it is unnecessary.

  An actual wafer level lens is generally configured by mounting parts such as an aperture stop and a cover glass for protecting the image plane of the wafer level lens on the wafer level lens 110.

  Further, the number of lenses included in the wafer level lens according to the present invention is not limited to two, and may be one or three or more.

  When the number of lenses is one, no lens array unit is formed, and instead of the lens array unit, one lens array is cut to manufacture the wafer level lens.

  On the other hand, when the number of lenses is three or more, three or more lens arrays are used, but adjacent lens arrays are bonded together to form one lens array unit, and the lens array unit is cut. Thus, the wafer level lens is manufactured.

  It is also possible to configure the wafer level lens 110 using the lens array 130 according to the procedure shown in FIGS. 1A to 1D. In this case, the wafer is perpendicular to the optical axis 110c. In the cross section of the level lens 110, the effective area 133 is not circular.

  That is, even when the effective area of a lens whose effective area is circular (a general lens having rotational symmetry) in the cross section of the wafer level lens 110 that is perpendicular to the optical axis 110c is partially deleted, It is possible to realize the wafer level lens according to the present embodiment.

[Configuration of Camera Module Having Imaging Lens According to Embodiment]
FIG. 4 is a cross-sectional view illustrating an example of the configuration of a camera module including the imaging lens illustrated in FIG. 1D, and a plan view illustrating the configurations of an imaging lens and an imaging element corresponding thereto.

  A camera module (imaging module) 140 shown in FIG. 4 is configured by incorporating a wafer level lens 110 shown in FIG. 1D into a lens barrel 141.

  The lens barrel 141 incorporates the wafer level lens 110 and is, for example, a cylindrical member.

  The wafer level lens 110 is incorporated in the lens barrel 141 so that all lens surfaces face the length direction of the lens barrel 141. On the other hand, the side surface of the wafer level lens 110 incorporated in the lens barrel 141 is fixed by the side surface of the lens barrel 141.

  The camera module 140 shown in FIG. 4 further includes a lens holder 142, a mechanism system 143 such as an AF (autofocus), an image sensor 144, and a base material 145.

  The lens holder 142 is a housing that houses the wafer level lens 110 and the lens barrel 141.

  The AF system 143 has an autofocus function in the camera module 140. The AF system 143 has various functions in addition to the autofocus function.

  The imaging device 144 is configured by a solid-state imaging device such as a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor). The image sensor 144 receives an image formed by the wafer level lens 110 as light.

  The base material 145 is one on which the image sensor 144 is mounted.

  The imaging device 144 includes a light receiving unit 144R that is a target on which the wafer level lens 110 collects light. The light receiving unit 144R performs the light reception in the image sensor 144.

  When the light receiving unit 144R is viewed as a flat member facing the wafer level lens 110 side, the vertical dimension is ax and the horizontal dimension is bx. That is, the aspect ratio of the light receiving unit 144R is a: b.

  The imaging element 144 has a cross-sectional shape perpendicular to the optical axis 110c of the wafer level lens 110, that is, the vertical dimension in the outer shape of the imaging element 144 is ay, and the horizontal dimension is by. . In other words, the aspect ratio of the outer shape of the image sensor 144 is a: b.

  On the other hand, the wafer level lens 110 has a vertical dimension of az and a horizontal dimension of bz. That is, in the outer shape of the wafer level lens 110, the ratio of the vertical dimension to the horizontal dimension is a: b. The ratio a: b is equal to the aspect ratio of the light receiving unit 144R and the external aspect ratio of the imaging element 144. Therefore, the wafer level lens 110 has an outer shape (a shape of a cross section perpendicular to the optical axis 110c of the outer peripheral regions 184 and 184A) similar to the outer shapes of the light receiving unit 144R and the imaging device 144. .

  Note that the letters x and y indicating the dimensions are both positive numbers.

  When the ratio of the vertical dimension to the horizontal dimension in the outer shape of the wafer level lens 110 is a: b, the aspect ratio of the light receiving unit 144R and the aspect ratio of the outer shape of the imaging element 144 are the same. Of these, at least one may be a: b. It is not essential that both the aspect ratio of the light receiving unit 144R and the aspect ratio of the outer shape of the imaging element 144 be a: b.

  Further, the wafer level lens 110 is centered on each part of the effective areas 183 and 183A corresponding to the center 144Rc of the light receiving unit 144R with respect to the outer shape of the wafer level lens 110 and the shape of the light receiving unit 144R. And / or the wafer level lens 110 is related to the outer shape of the wafer level lens 110 and the imaging device 144, and is centered on each part of the effective areas 183 and 183A corresponding to the center 144c in the outer shape of the imaging device 144.

  In FIG. 4, the wafer level lens 110 is centered on each part of the effective areas 183 and 183A corresponding to the center 144Rc, and is centered on each part of the effective areas 183 and 183A corresponding to the center 144c. . In FIG. 4, the center in the effective region 183 is illustrated as a center 183c, and the center in the effective region 183A is illustrated as a center 183Ac.

  The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope shown in the claims, and embodiments obtained by appropriately combining technical means disclosed in different embodiments. Is also included in the technical scope of the present invention.

  The present invention can be used for a wafer level lens.

110 Wafer level lens (imaging lens)
110c Optical axis 112 Lens array unit 130 Lens array 131 Wafer 132 Lens 133 Effective area 134a-134g Lens row (horizontal)
135a to 135g Lens array (vertical)
136 Cutting margin 138t Horizontal edge 138v Vertical edge 140 Camera module (imaging module)
144 Image sensor 144R Light-receiving part 180 Lens array 180A Lens array 181 Wafer 182 Lens 182A Lens 183 Effective area 183A Effective area 184 Outer area 184A Outer area aw Vertical dimension bw Horizontal dimension

Claims (7)

An imaging lens manufactured by cutting out one of the lenses from a lens array in which a plurality of lenses are arranged on the same surface of the wafer,
The shape of the cross section perpendicular to the optical axis of the imaging lens in the outer peripheral area provided in the outer periphery of the effective area of the imaging lens is similar to the shape of the light receiving unit that collects light by the imaging lens. An imaging lens characterized by the above.   The imaging lens according to claim 1, wherein a plurality of similar lenses are bonded adjacent to each other in the direction of the optical axis.   The imaging lens according to claim 1, wherein the effective area is not circular in a cross section perpendicular to the optical axis of the imaging lens. In a plan view of the lens array, a plurality of lenses having an effective area in which the vertical edges are arcuate and the horizontal edges are linear are arranged on the wafer so as to be aligned in the vertical and horizontal directions. And
Each of the plurality of lenses has a ratio of the vertical dimension to the horizontal dimension of 3: 4 or 9:16,
A lens array, wherein the effective areas of the lenses constituting one column in the vertical direction are arranged in series. An imaging lens manufacturing method manufactured by cutting out one of the lenses from a lens array in which a plurality of lenses are arranged on the same surface of a wafer,
The shape of the cross section perpendicular to the optical axis of the imaging lens in the outer peripheral area provided in the outer periphery of the effective area of the imaging lens is similar to the shape of the light receiving unit that collects light by the imaging lens. Thus, the manufacturing method of the imaging lens characterized by including the process of cutting out from the said lens array. A step of manufacturing a lens array unit by bonding the lens arrays adjacent to each other in the direction of the optical axis using a plurality of the lens arrays;
6. The method of manufacturing an imaging lens according to claim 5, further comprising: cutting out one lens for each lens array from the lens array unit. The imaging lens according to any one of claims 1 to 3,
An imaging module comprising: an imaging device comprising the light receiving unit.

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