Patent Publication Number: US-11639783-B2

Title: Light source device and lens structure

Description:
CROSS-REFERENCE TO RELATED PATENT APPLICATIONS 
     The present application claims priority under 35 U. S. C. § 119 to Japanese Patent Application No. 2020-186519, filed on Nov. 9, 2020, and Japanese Patent Application No. 2021-084692, filed on May 19, 2021, the contents of which are hereby incorporated by reference in their entireties. 
     BACKGROUND 
     The present disclosure relates to a light source device and a lens structure. 
     There have been disclosed a composite lens having a compression-molded lens part and a frame part surrounding the lens part that are solidly joined by injection molding. 
     SUMMARY 
     A mold for such a composite lens includes an upper mold and a lower mold, each of the upper mold and the lower mold includes a core for a lens portion, a core for a flange portion, and a core for a frame portion. Although each of the core portions can be moved independently in a method of manufacturing a composite lens, many steps are required in manufacturing composite lenses (for example, refer to JP 2013-202810 A). 
     An object of the present disclosure is to provide a light source device and a lens structure having good adhesion between a support part and a lens. 
     A light source device according to one embodiment of the present disclosure includes a light source having an upper surface including a light-emitting surface, the light source comprising a plurality of light-emitting parts arranged in a two-dimensional array; a lens located above and spaced apart from the light-emitting surface of the light source, the lens including an optically functional part and a flange part located along an outer periphery of the optically functional part; and a support part formed of a light-shielding material, the support part configured to support at least the flange part of the lens. The optically functional part includes a first surface and a second surface, the first surface being located at opposite side from the light source and the second surface being located at an opposite side from the first surface and facing the light source. The first surface has a surface area greater than a surface area of the second surface, and the first surface and the second surface each covers the plurality of light-emitting parts in a plan view. The flange part includes a third surface and a fourth surface, the third surface being located at a same side of the first surface and the fourth surface being located at the same side of the second surface. The flange part is formed with at least one first recess in the fourth surface. 
     A lens structure according to one embodiment of the present disclosure includes a lens including an optically functional part and a flange part located along an outer periphery of the optically functional part; and a support part formed of a light-shielding material and configured to support at least the flange part of the lens. The lens and the support part are molded in one body through double-shot molding, the optical functional part includes a first surface and a second surface located on a side opposite from the first surface, the first surface has a surface area greater than a surface area of the second surface, the flange part has a third surface located on a same side as the first surface, and a fourth surface located on a same side as the second surface, and the flange part defines at least one first recess in the fourth surface. 
     According to certain embodiments of the present disclosure, a light source device and a lens structure having good adhesion between a support part and a lens can be provided. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1 A  is a schematic top view showing a light source device according to certain embodiments of the present disclosure. 
         FIG.  1 B  is a schematic cross-sectional view taken along line  1 B- 1 B of  FIG.  1 A . 
         FIG.  2 A  is a schematic top view of a lens structure according to one embodiment. 
         FIG.  2 B  is a schematic bottom view of a lens structure according to one embodiment. 
         FIG.  2 C  is a schematic cross-sectional view taken along line  2 C- 2 C of  FIG.  2 A  and  FIG.  2 B . 
         FIG.  3 A  is a schematic bottom view of a lens according to one embodiment. 
         FIG.  3 B  is a schematic cross-sectional view taken along line  3 B- 3 B of  FIG.  3 A . 
         FIG.  4 A  is a schematic bottom view of another lens according to one embodiment. 
         FIG.  4 B  is a schematic bottom view showing still another lens according to one embodiment. 
         FIG.  5 A  is a schematic top view showing a light source according to one embodiment. 
         FIG.  5 B  is a schematic cross-sectional view taken along line  5 B- 5 B of  FIG.  5 A . 
         FIG.  5 C  is an enlarged schematic cross-sectional view of a portion of a light source. 
         FIG.  6 A  is a schematic cross-sectional view illustrating a step of manufacturing a light source device according to one embodiment. 
         FIG.  6 B  is a schematic cross-sectional view illustrating a step of manufacturing a light source device according to one embodiment. 
         FIG.  6 C  is a schematic cross-sectional view illustrating a step of manufacturing a light source device according to one embodiment. 
         FIG.  6 D  is a schematic cross-sectional view illustrating a step of manufacturing a light source device according to one embodiment. 
         FIG.  6 E  is a schematic cross-sectional view illustrating a step of manufacturing a light source device according to one embodiment. 
         FIG.  7 A  is an enlarged schematic cross-sectional view of a portion of a lens according to Variational Example 1. 
         FIG.  7 B  is an enlarged schematic cross-sectional view taken along line  7 B- 7 B of  FIG.  7 A . 
         FIG.  8 A  is an enlarged schematic cross-sectional view of a portion of a lens according to Variational Example 2. 
         FIG.  8 B  is an enlarged schematic cross-sectional view taken along line  8 B- 8 B of  FIG.  8 A . 
         FIG.  9 A  is an enlarged schematic cross-sectional view of a portion of a lens according to Variational Example 3. 
         FIG.  9 B  is an enlarged schematic cross-sectional view taken along line  9 B- 9 B of  FIG.  9 A . 
         FIG.  10 A  an enlarged schematic cross-sectional view of a portion of a lens according to Variational Example 4. 
         FIG.  10 B  is an enlarged schematic cross-sectional view taken along line  10 B- 10 B of  FIG.  10 A . 
         FIG.  11    is a schematic cross-sectional view illustrating another example of a light source device according to one embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Certain embodiments of the present invention will be described below with reference to the accompanying drawings. It is to be noted that the light source device described below is intended for implementing the technical concepts of the present invention, and the present invention is not limited to the described embodiments below unless otherwise specified. Description given in one embodiment can also be applied in other embodiments and variational examples. The sizes or positional relationships of the members shown in the drawings are occasionally shown exaggerated for the sake of clarity. 
     In the description below, the same designations or the same reference numerals denote the members having functions substantially the same and description thereof may be appropriately omitted. Components that are not referenced in the description may not be marked with a reference character. In the description below, terms that indicate specific directions or locations (for example, “up,” “down,” “right,” “left,” and other terms expressing such directions or locations) may be applied. Those terms are used to express relative directional relationship and positional relationship between the components in a drawing that is referred to for the ease of understanding. In the present specification, terms such as “upper” and “lower” are used to illustrate a relative locational relationship between the components in a drawing that is referred to, and unless specifically indicated, are not intended to show an absolute positional relationship. In the present specification, the term “parallel” indicates that the angle formed between two straight lines, two sides, two surfaces, etc., is in a range of about 0°+/−5°, unless otherwise indicated. In addition, the term “perpendicular” or “orthogonal” indicates that the angle formed between two straight lines, two sides, two surfaces, etc., is in a range of about 90°+/−5°. 
     In certain drawings shown below, x-axis, y-axis, and z-axis orthogonal to one another are indicated. The x direction along the x-axis indicates a predetermined direction in an arrangement plane where the light source of the light source device according to one embodiment is arranged (in other words, in an arrangement plane where the light-emitting parts are arranged). The y direction along the y-axis indicates a direction orthogonal to the x direction in the light source arrangement plane. The z direction along the z-axis indicates the direction orthogonal to the arrangement plane. In the x direction, the direction in which the arrow is pointing is represented as the +x direction and the direction opposite to the +x direction is represented as the −x direction. In the y direction, the direction in which the arrow is pointing is represented as the +y direction and the direction opposite to the +y direction is represented as the −y direction. In the z direction, the direction in which the arrow is pointing is represented as the +z direction and the direction opposite to the +z direction is represented as the −z direction. In the present embodiment, the light source is adapted to emit light in the +z direction, for example. However, this does not limit the orientation of the light source device and the lens structure when used, and the orientation of the light source device and of the lens structure can be appropriately determined. 
     Hereinafter, example embodiments will be described illustrating a flashlight for smartphone that includes a light source device and a lens structure according to the embodiments. 
     Embodiments 
       FIG.  1 A  and  FIG.  1 B  are diagrams illustrating a light source device  200  according to a first embodiment of the present disclosure.  FIG.  1 A  is a schematic top view showing a light source device  200 .  FIG.  1 B  is a schematic cross-sectional view of the light source device  200 , taken along line  1 B- 1 B of  FIG.  1 A . 
     The light source device  200  includes a light source  30 , a lens  10 , and a support part  20 . 
     The light source  30  includes a plurality of light-emitting parts  30 U arranged in a two dimensional array. The lens  10  is arranged above a light-emitting surface  30   a  of the light source  30  (in the +z direction), spaced apart from the light source  30 . The lens  10  includes an optically functional part  11  and a flange part  12  arranged along the outer periphery  11 P of the optically functional part  11 . The support part  20  is formed of a light-shielding material and is configured to support at least the flange part  12  of the lens  10 . In the present specification, a structure including the lens  10  and the support part  20  is referred to as a “lens structure.” 
     The optically functional part  11  includes a first surface  11   a  located on an opposite side from the light source  30 , and a second surface  11   b  located on an opposite side from the first surface  11   a  and facing the light source  30 . The first surface  11   a  and the second surface  11   b  each covers the plurality of light-emitting parts  30 U in a plan view. A surface area of the first surface  11   a  is greater than a surface area of the second surface  11   b.    
     The flange part  12  has a third surface  12   a  located on the same side as the first surface  11   a , and a fourth surface  12   b , located on the same side as the second surface  11   b . The flange part  12  is formed with at least one first recess  13  in the fourth surface  12   b.    
     In the present embodiment, the lens  10  is formed using a light-transmissive material. The support part  20  can be formed of a light-shielding resin member. In order to mold different materials such as the lens  10  and the support part  20  into a single piece, a double-shot molding method described below can be employed. Through a double-shot molding method, the lens  10  and the support part  20  can be molded into a single piece without using an adhesive, even when the lens  10  is molded prior to molding the support part  20 . Note that the base material of the lens  10  and the base material of the support part  20  can be the same or different, and further, can contain different substances. According to the present embodiment, forming the at least one first recess  13  in the fourth surface  12   b  of the flange part  12  of the lens  10  can improve the adhesion between the lens  10  and a mold (lower mold) at a lower surface side of the lens  10 , when a primary molded lens  10  is formed in a double-shot molding process described below. As a result, after the lens  10  is molded and the mold is opened, the lens  10  can be separated from a mold (upper mold) on an upper surface side of the lens  10  while the lens  10  remains in the lower mold. It is therefore possible to form the support part  20  as a secondary molded article in succession after molding the lens  10 . 
     In the present embodiment, the at least one first recess  13  is formed in the flange part  12 , which is located outside the optically functional part  11 . This will reduce the effect of the at least one first recess  13  on the optical performance of the optically functional part  11 . 
     Each constituent member will be described in detail below. 
     1. Lens Structure 
       FIG.  2 A  is a schematic top view of the lens structure  100 .  FIG.  2 B  is a schematic bottom view of the lens structure  100 .  FIG.  2 C  is a schematic cross-sectional view taken along line  2 C- 2 C of  FIG.  2 A  and  FIG.  2 B . 
     The lens structure  100  includes the lens  10  and the support part  20  formed of a light-shielding material. The lens  10  and the support part  20  are preferably solidly joined. The lens  10  and the support part  20  can be molded in one body through double-shot molding. In the present embodiment, the term “molded in one body through double-shot molding” refers to a molded article made of different materials and/or different colors that are bonded together without using an adhesive. 
     As shown in  FIG.  1 A  and  FIG.  1 B , in the present embodiment, the support part  20  is oriented in the +z direction relative to the light-emitting surface  30   a  of the light source  30 , and holds the lens  10  at a position where the light from the light-emitting surface  30   a  enters the optically functional part  11 . The light source device  200  can also include a substrate  40  on which the light source  30  is arranged, where the end part of the support part  20  at the light source  30  side can be secured to the first surface  40   a  of the substrate  40 . This allows a stable holding of the lens  10  at a predetermined location in relation to the light-emitting surface  30   a.    
     The support part  20  can be formed with an opening  25  such that at least a portion of the optically functional part  11  of the lens  10  is exposed at an opposite side relative to the light source  30 . Light from the light source  30  incident on the lens  10  is emitted from the upper surface of the lens  10  through the opening  25 . 
     Lens  10   
       FIG.  3 A  is a schematic top view of the lens  10 , and  FIG.  3 B  is a schematic cross-sectional view taken along line  3 B- 3 B of  FIG.  3 A . 
     In the present embodiment, the outer shape of the lens  10  is an approximately circular shape in a plan view, with a diameter L 1  preferably in a range of 3.0 to 10.0 mm, for example, about 6.05 mm. The lens  10  has a thickness L 2  preferably in a range of 1.0 to 5.0 mm, for example, about 3.2 mm. The outer shape of the lens  10  in a plan view can be appropriately determined. For example, if the lens  10  includes a plurality of lens parts arranged in a two-dimensional array, the outer shape of the lens  10  in the plan view may be an approximately rectangle. 
     The lens  10  includes the optically functional part  11  and the flange part  12 , which is located on the outer side of the optically functional part  11  along the outer periphery  11 P of the optically functional part  11 . The optically functional part  11  has a first surface  11   a  and a second surface  11   b  located opposite side from the first surface  11   a . The first surface  11   a  is located opposite side form the light source and the second surface  11   b  is located facing the light source. The flange part  12  has a third surface  12   a , located on the same side as the first surface  11   a , and a fourth surface  12   b , located on the same side as the second surface  11   b . The flange part  12  is formed with at least one first recess in the fourth surface  12   b . The flange part  12  can further include an outer lateral surface  12   c  adjacent to the third surface  12   a  and to the fourth surface  12   b.    
     The lens  10  has an upper surface  10   a  and a lower surface  10   b . The upper surface  10   a  of the lens  10  includes the first surface  11   a  of the optically functional part  11  and the third surface  12   a  of the flange part  12 . The lower surface  10   b  of the lens  10  includes the second surface  11   b  of the optically functional part  11  and the fourth surface  12   b  of the flange part  12 . 
     In the present specification, “outer periphery  11 P of the optically functional part  11 ” is defined, for example, by the outer edge of the first surface  11   a  of the optically functional part  11  at the upper surface  10   a  of the lens  10 . In the example shown in  FIG.  3 A  and  FIG.  3 B , the convex portion of the upper surface  10   a  of the lens  10  is the first surface  11   a  of the optically functional part  11 , and the approximately flat portion of the upper surface of the lens  10  located outer side of the first surface  11   a  is the third surface  12   a  of the flange part  12 . Of the lower surface  10   b  of the lens  10 , the portion overlaps the first surface  11   a  in a plan view is the second surface  11   b  of the optically functional part  11 , and the portion located at an outer side of the second surface  11   b  is the fourth surface  12   b  of the flange part  12 . The fourth surface  12   b  contains an approximately flat surface. The fourth surface  12   b , may contain a curved surface continuous to the second surface  11   b  of the optically functional part  11 . 
     Optically Functional Part  11   
     The optically functional part  11  is configured to refract light passing through the optically functional part  11  from each of the light-emitting parts  30 U of the light source  30 , and to emit light in predetermined directions. The optically functional part  11  can function as a convex lens such as a biconvex lens, a flat convex lens, or a convex meniscus lens, as a concave lens such as a biconcave lens, a flat concave lens, or a concave meniscus lens, or as a Fresnel lens. 
     In the present embodiment, the optically functional part  11  functions as a convex lens having a single optical axis with respect to the light-emitting surface  30   a  of the light source  30 . This allows the light emitted from the light-emitting surface  30   a  to be projected into the area of irradiation that is point-symmetric with respect to a single point on the optical axis. For example, when the plurality of light-emitting parts  30 U of the light source  30  are individually turned on (hereinafter referred to as “partial drive”), illumination light having an intensity distribution corresponding to the light emission distribution of the light source  30  can be projected into the irradiation area as described below. 
     The optically functional part  11  can have a plurality of optical axes with respect to the light-emitting surface of  30   a  of the light source  30 . For example, the optically functional part  11  can include a plurality of lens parts that have different optical axes from one another. Each of the lens parts can be arranged to correspond to one or more of the light-emitting parts  30 U of the light source  30 . 
     The first surface  11   a  of the optically functional part  11  has surface area greater than the surface area of the second surface  11   b  of the optically functional part  11 . The first surface  11   a  preferably have a surface area in a range of two times to four times greater than a surface area of the second surface  11   b . In the present embodiment, the first surface  11   a  has a surface area preferably in a range of 15.0 to 40.0 mm 2 , for example, about 27.9 mm 2 . The second surface  11   b  preferably have a surface area in a range of 10.0 to 35.0 mm 2 , for example, about 22.1 mm 2 . 
     The shape of the first surface  11   a  and the second surface  11   b  can be appropriately determined. For example, the first surface  11   a  and the second surface  11   b  can each be a convex surface or a concave surface. In this case, the curvature radius of the first surface  11   a , which is a convex surface or a concave surface, can be smaller than the curvature radius of the second surface  11   b , which is a convex surface or a concave surface. The first and second surfaces  11   a  and  11   b  can be such that the first surface  11   a  includes a convex surface or a convex surface while the second surface  11   b  is a flat surface. For example, the first surface  11   a  includes concave and convex structures that acts as a Fresnel lens, while the second surface  11   b  is a flat surface. 
     In the example shown in the figures, the outer shape of the optically functional part  11  in the plan view is an approximately circular shape. The first surface  11   a  and the second surface  11   b  of the optically functional part  11  of the lens  10  are both convex surfaces, and the optically functional part  11  functions as a convex lens having a single optical axis. The optical axis of the convex lens can be in parallel to the z-axis. The optically functional part  11  preferably has a focus distance in a range of 3 to 5 mm. 
     In the example shown in the figures, the curvature radius of the first surface  11   a  is smaller than the curvature radius of the second surface  11   b . The first surface  11   a  has a curvature radius preferably in a range of 1.5 to 3.0 mm, for example, 2.4 mm. The second surface  11   b  has a curvature radius preferably in a range of 5.0 to 30.0 mm, for example, 10.0 mm. 
     The lens diameter of the first surface  11   a  (the diameter of the first surface  11   a  in a plan view) LD 1  is, for example, preferably in a range of 3.0 to 5.0 mm, for example about 4.21 mm. The first surface  11   a  has a maximum height HL, for example, preferably in a range of 1.0 to 4.0 mm, for example, about 2.34 mm. In the present embodiment, the term “maximum height HL” of the first surface  11   a  refers to a length along the z-axis between the third surface  12   a  and the vertex of the first surface  11   a.    
     As shown in the figures, the lower surface  10   b  of the lens  10  may have a convex surface with a lens diameter of LD 2  that is greater than a lens diameter of the first surface  11   a  LD 1 . In this case, a portion of the convex surface formed on the lower surface  10   b  serves as the second surface  11   b  of the optically functional part  11 . The lens diameter LD 2  is, for example, preferably in a range of 4.0 to 6.0 mm, for example, about 5.3 mm. 
     Flange Part  12   
     The flange part  12  can be positioned along the entire outer periphery  11 P of the optically functional part  11 . In the example shown in the figures, the outer lateral surface  12   c  of the flange part  12  is outward of the outer periphery  11 P of the optically functional part  11 , and extends approximately parallel to the outer periphery  11 P, in a plan view. The flange part  12  has a width w 1  preferably in a range of 0.7 to 1.1 mm, for example 0.92 mm. The flange part  12  has a thickness d 1  preferably in a range of 0.3 to 0.7 mm, for example 0.5 mm. The thickness d 1  of the flange part  12  refers to a shortest distance between the third surface  12   a  and a portion of the fourth surface adjacent to the outer lateral surface  12   c  of the flange part  12 , exclusive of the portion of the fourth surface defining the at least one first recess  13 . 
     The flange part  12  is formed with at least one first recess  13  in the fourth surface  12   b . This arrangement will increase the contact area between the lower surface  10   b  of the lens  10  and the lower mold in the double-shot molding process described below, which can increase the adhesion between the lens  10  and the lower mold. This arrangement makes it possible to more reliably separate the lens  10  from the upper mold when the mold is opened to release the lens  10 , while holding the lens  10  held on the lower mold. Therefore, after molding the lens  10 , the support part  20 , that is a secondary molded article can be molded continuously. 
     The at least one first recess  13  is defined in the flange part  12  that is located outside of the optically functional part  11 , the effect of the at least one first recess  13  on the optical action of the optically functional part  11  can be reduced or prevented. The at least one first recess  13  is preferably formed spaced apart from the outer periphery  11 P of the optically functional part  11 . With this arrangement, the effect of the at least one first recess  13  on the optical action of the optically functional part  11  can be further reduced or prevented. 
     The at least one first recess  13  can be defined with an appropriate shape in a plan view. The at least one first recess  13  can be formed in a groove shape extending along the outer periphery  11 P of the optically functional part  11 . The first recess  13  can be formed in a circular shape, an elliptic shape, or a rectangular shape in a plan view. The lateral surface(s) defining the at least one first recess  13  can be approximately perpendicular to the third surface  12   a  of the flange part  12 , or can be inclined with respect to a plane that is perpendicular to the third surface  12   a . The corners of the at least one first recess  13  can be formed with a rounded corner or rounded corners (R-shaped) in a cross-sectional view, at a portion or portions opposite to the opening of the first recess  13 . 
     The flange part  12  can be formed with a plurality of the first recesses  13 . The arrangement, an arrangement pitch, etc., of the plurality of the first recesses  13  can be appropriately determined. For example, the plurality of the first recesses  13  can be arranged spaced apart from one another along the outer periphery  11 P of the optically functional part  11 . When the width w 1  of the Flange part  12  is large enough, two or more of the first recesses  13  can be arranged in the width direction of the flange part  12 . From the viewpoint of preventing occurrence of retention of the lens  10  in the upper mold when demolding the molded lens  10  to be described below, the plurality of the first recesses  13  are preferably arranged approximately evenly spaced apart from one another along the entire outer periphery of the flange part  12 . 
     In the example shown in  FIG.  3 A  and  FIG.  3 B , the first recess  13  is a groove that surrounds the optically functional part  11  in a plan view. The lateral surfaces defining the first recess  13  include, for example, a first lateral surface  13   s   1  along the outer periphery  11 P of the optically functional part  11 , and a second lateral surface  13   s   2  facing the first lateral surface  13   s   1  and located closer to the optically functional part than the first lateral surface  13   s   1 . Providing the first recess  13  in a form of a groove surrounding the optically functional part  11  can enhance adhesion of the entire flange part  12  of the lens  10  with the lower mold in a step of demolding a first molded article. 
     The first recess  13  is formed with a width w 2  that is preferably ½ or less, more preferably ⅓ or less with respect to a width w 1  of the flange part  12 . The width of the first recess  13  is, for example, preferably in a range of 0.25 to 0.60 mm, for example, about 0.30 mm. The first recess  13  is formed with a depth from the fourth surface  12   b  (i.e., a maximum length in the z-axis direction) d 2  that is preferably ½ or greater with respect to a thickness d 1  of the flange part  12 . From the perspective of the strength of lens  10 , the depth d 2  of the first recess  13  can be set to ⅘ or less with respect to the thickness d 1  of the flange part  12 . The depth d 2  of the first recess  13  is preferably in a range of 0.25 to 0.40 mm. 
       FIG.  4 A  and  FIG.  4 B  are each a bottom view of the lens  10 , to illustrate other examples of the first recess  13 . As shown in  FIG.  4 A  and  FIG.  4 B , a plurality of the first recesses  13  are arranged spaced apart from one another in the fourth surface  12   b  of the flange part  12 . The plurality of the first recesses  13  can be arranged with approximately equal spacing along the outer periphery  11 P. 
     In the example shown in  FIG.  4 A , each of the first recesses  13  is a groove that extends along a portion of the outer periphery  11 P of the optically functional part  11  in a plan view. The lateral surfaces defining each of the first recesses  13  includes include, for example, a first lateral surface  13   s   1  and a second lateral surface  13   s   2 , which are approximately in parallel to the outer periphery  11 P, and a third lateral surface  13   s   3  and a fourth lateral surface  13   s   4 , which extend in directions crossing the outer periphery  11 P in a plan view. The lateral surfaces defining each of the first recesses  13  containing a plurality of lateral surfaces extending in different directions in a plan view, can improve adhesion between the lower surface  10   b  of the lens  10  and the lower mold. As shown in  FIG.  4 B , each of the first recesses  13  can be formed in a circular shape in a plan view. 
     Other than the configurations illustrated in  FIG.  3 A ,  FIG.  3 B ,  FIG.  4 A , and  FIG.  4 B , the shape, the arrangement, and the number of the first recesses  13  can be appropriately determined. As described below, the at least one first recess  13  can be formed with at least one protrusion and/or at least one second recess in at least one of the lateral surfaces defining the at least one first recess. This arrangement can further improve the adhesion of the lower surface  10   b  of the lens  10  and the lower mold during mold opening after molding the lens  10  in a double-shot molding process to be described further below. Accordingly, occurrence of retention of the lens  10  in the upper mold can be efficiently reduced or prevented. 
     The fourth surface  12   b  of the flange part  12  can be formed with a plurality of the first recesses  13  defined by different shapes. For example, the plurality of the first recesses  13  can include the first recess (groove)  13  formed in an annular shape as shown in  FIG.  3 A  and  FIG.  3 B , and the first recess  13  formed in a circular shape (or a rectangular shape) as shown in  FIG.  4 B , in a planar view. 
     The lens  10  can be formed of a light-transmissive resin, for example, a thermoplastic resin. Examples of the thermoplastic resin include polycarbonate, acrylic, cyclic polyolefin, polyethylene terephthalate, and polyester. Thermoplastic resin materials are preferred because they can be manufactured efficiently by injection molding. Of those, it is preferable to use polycarbonate, which has high transparency and is inexpensive. Alternatively, the lens  10  can be formed of a thermosetting resin, such as silicone resin or epoxy resin. 
     Support Part  20   
     As shown in  FIG.  2 A  to  FIG.  2 C , the support part  20  is configured to support at least the flange part  12  of the lens  10 . The support part  20  can be in contact with at least a part of the third surface  12   a  and/or at least a part of the outer lateral surface  12   c  of the flange part  12 . 
     In the present embodiment, the support part  20  has a contact surface  20 S that is in contact with at least part of the third surface  12   a  of the flange part  12 . The support part  20  can be in contact with the entire third surface  12   a  of the flange part  12 . The support part  20  preferably covers an entirety of the third surface  12   a  and of the outer lateral surface  12   c  of the flange part  12 . This allows the support part  20  to support the lens  10  (in detail, the flange part  12  of the lens  10 ) in a stable manner. 
     The support part  20  can be positioned to at least partially overlapping the at least one first recess  13  of the flange part  12  of the lens  10  in a plan view. In other words, the contact surface  20 S of the support part  20  that is in contact with the third surface  12   a  of the flange part  12 , and at least one of the first recesses  13  of the flange part  12 , can at least partially overlap with each other. With this arrangement, the at least one first recesses  13  are at locations not to affect the optical action of the optically functional part  11 . As shown in the  FIG.  2 B , it is preferable that the contact surface  20 S of the support part  20  covers the entirety of the at least one first recess  13  in a plan view. 
     When the flange part  12  is formed with a plurality of the first recesses  13 , the contact surface  20 S of the support part  20  may at least partially cover the plurality of the first recesses  13  in a plan view, but preferably covers all the plurality of the first recesses  13  in a plan view. 
     In the example shown in the figures, the support part  20  includes a first hood portion  21 , a second food portion  22 , a first flange portion  23 , and a second flange portion  24 . 
     The first hood portion  21  and the second hood portion  22  have a cylindrical or other cylindrical outer shape that is tapered toward the direction in which light is emitted. In other words, the first hood portion  21  and the second hood portion  22  are tilted toward the optical axis of the convex lens along the +z direction. The first hood portion  21  extends from the third surface  12   a  of the flange part  12 , in an opposite direction to the light source. The first hood portion  21  preferably has a shape tapering in the +z direction. The second hood portion  22  extends from the outer lateral surface  12   c  of the flange part  12  to the light source side. The second hood portion  22  can be secured to the substrate where the light source is located. 
     It is preferable that the first hood portion  21  at least partially overlaps with at least one of the first recesses  13  of the flange part  12  in a plan view, and it is more preferable that the first hood portion overlaps with the entirety of the first recesses  13  in a plan view. The first recesses  13  are preferably arranged inward of the second hood portion  22  in a plan view. Further, it is preferable that the support part  20 , including the first hood portion  21  and the second hood portion  22 , is not in contact with a portion of the flange part defining at least one of the first recesses  13 . This allows the support part  20  to support the lens  10  (in detail, the flange part  12  of the lens  10 ) in a stable manner. It can also reduce or prevent light from the light source  30  from leaking outside the support part  20  (in detail, outer side of the +/−x direction or +/−y direction of the first and second hood portions  21 ,  22 ). 
     The outer surface of the first hood portion  21  can be located inward of the outer surface of the second hood portion  22  in a plan view. In this case, the support part  20  can include a first flange portion  23  located outer side with respect to the first hood portion  21  and also at an upper end (in the +z direction) of the second hood portion  22 . The first flange portion  23  surrounds the first hood portion  21  in a plan view. The first flange portion  23  has an approximately flat upper surface and a lateral surface continuous with the outer lateral surface of the second hood portion  22 . 
     The second flange portion  24  of the support part  20  covers an edge portion of the first surface  11   a  of the optically functional part  11 . In the present embodiment, the opening  25  of the support part  20  is defined by an inner edge of the second flange portion  24  of the support part  20 . The second flange portion  24  of the support part  20  can be located between the first hood portion  21  and the optically functional part  11 . The second flange portion  24  of the support part  20  can serve as a diaphragm of the optically functional part  11 . 
     In the present embodiment, the support part  20  has a maximum width S 1  preferably in a range of 4.0 to 15.0 mm, for example about 6.9 mm, and a height S 2  preferably in a range of 1.5 to 7.0 mm, for example 4.03 mm. The “maximum width S 1 ” of the support part  20  refers to a maximum width of the outer shape of the second hood portion  22 . The “height S 2 ” of the support part  20  refers to a length between a lower end of the second hood portion  22  and an upper end of the first hood portion  21  along the z-axis direction. 
     The first hood portion  21  has a height H 1  that can be set to be, for example, approximately equal to the maximum height HL of the first surface  11   a  of the optically functional part  11 , or greater than the maximum height HL. The “height H 1  of the first hood portion  21 ” refers to a length along the z-axis direction between the third surface  12   a  and the upper end of the first hood portion  21 . The height H 1  of the first hood portion  21  is preferably in a range of 1.1 to 4.1 mm, for example 2.44 mm. 
     The second hood portion  22  has a height H 2  that is set so that a space is formed between the second surface  11   b  of optically functional part  11  and the light-emitting surface  30   a  of the light source  30 . The “height H 2  of the second hood portion  22 ” refers to a length along the z-axis direction between the third surface  12   a  and the lower end of the second hood portion  22 . The height H 2  of the second hood portion  22  is, for example, preferably in a range of 0.5 to 3.0 mm, for example 1.59 mm. 
     The second flange portion  24  of the support part  20  has a thickness H 3  from the third surface  12   a  of the flange part  12  is, for example, preferably in a range of 0.1 to 0.5 mm, for example, 0.3 mm. 
     Other than those described above, the support part  20  can have an appropriate structure. The support part  20  may not be formed with the first hood portion  21  or/and the second hood portion  22 . Depending on the shape of the outer surface of the support part  20 , the first flange portion  23  may not be formed. Further, the support part  20  may not formed with the second flange portion  24  of the support part  20 . 
     The support part  20  is formed of, for example, a dark-colored resin material. The support part  20  can contain a resin that is a base material and a colorant that is dispersed in the resin. As the base material, a thermoplastic resin can be used. Examples of the thermoplastic resin include polycarbonate, acrylic, cyclic polyolefin, polyethylene terephthalate, and polyester. It is preferable to use polycarbonate resin. The resin material used as the base material of the support part  20  and the resin material used for the lens  10  can be the same or different. By using the same resin material as the lens  10 , the adhesion between the lens  10  and the support part  20  can be improved. When the lens  10  is formed using thermosetting resin, the support part  20  may contain thermosetting resin as the base material. 
     Various kinds of dyes and/or pigments can be used appropriately as a colorant to be added to the resin that serves as the base material. Specific examples thereof include Cr 2 O 3 , MnO 2 , Fe 2 O 3 , and carbon black. 
     Positional Relation Between Lens Structure  100  and Light Source  30   
     As shown in  FIG.  1 A  and  FIG.  1 B , the opening  25  of the lens  10  is at least partially overlapped with the light-emitting surface  30   a  in a plan view. Preferably, the entire light-emitting surface  30   a  is located within the opening  25  of the lens  10  in a plan view. Accordingly, light emitted from the light-emitting surface  30   a  can be more efficiently emitted through the opening  25 . 
     The shortest distance between the light-emitting surface  30   a  of the light source  30  and the second surface  11   b  of optically functional part  11  of the lens  10  is preferably in a range of 0.1 to 0.7 mm, for example, 0.4 mm. Between the light-emitting surface  30   a  of the light source  30  and the lower surface of the lens  10  can be a hollow (air layer). Alternatively, a light-transmissive resin can be placed between the light-emitting surface  30   a  and the lower surface  10   b  of the lens  10 . 
     For flat-plane viewing, the size of opening  25  is set to be at least as large as the size of the light-emitting surface  30   a , for example. The area A1 of the opening  25  in a plan view can be in a range of 1.3 to 2.3 times of the area A2 of the light-emitting surface  30   a . In the present embodiment, the opening  25  is formed in a circular shape with a diameter of 4.21 mm, and the area A1 of the opening  25  is 13.92 mm 2 . The area A2 of the light-emitting surface  30   a  is 7.68 mm 2  (3.12 mm×2.46 mm). Therefore, the area ratio (A1/A2) of the opening  25  with respect to the light-emitting surface  30   a  in a plan view is 1.81. A preferable area ratio (A1/A2) can vary depending on the shortest distance D between the light-emitting surface  30   a  and the second surface  11   b  of the optically functional part  11 . 
     When the first surface  11   a  is a convex surface with a single optical axis, a portion of the first surface  11   a  of the lens  10  that is located in the opening  25  (i.e., portion not to covered by the support part  20 ) has a surface area A3 in a range of 2.5 to 4.5 times greater with respect to the area A2 of the light-emitting surface of the light source  30 . In the present embodiment, the surface area A3 of the first surface  11   a  located inside the opening  25  is 26.0 mm 2 , and the area A2 of the light-emitting surface  30   a  is 7.68 mm 2 . Therefore, the area ratio (A3/A2) of the surface area A3 of the first surface  11   a  with respect to the area A2 of the light-emitting surface  30   a  is 3.39. 
     2. Light Source 
       FIG.  5 A  is a schematic top view showing the light source  30  and  FIG.  5 B  is a schematic cross-sectional view taken along line  5 B- 5 B of  FIG.  5 A . 
     In the configurations shown in  FIG.  5 A  and  FIG.  5 B , the light source  30  has an approximately rectangular shape. Each side of the outer shape of the rectangular shape is in parallel to the x-axis or the y-axis shown in the figures. The outer shape of the light source  30  in a plan view does not have to be a rectangular shape. 
     The light source  30  is disposed, for example, on a first surface of the substrate  40  that includes wirings  42 . The substrate  40  has an outer shape of an approximately rectangular shape in a plan view. The substrate  40  can other shapes such as a circular shape. 
     The light source  30  has an upper surface including a light-emitting surface  30   a . The light source  30  includes a plurality of light-emitting parts  30 U arranged in a two dimensional array. In other words, the light-emitting surface  30   a  of the light source  30  is demarcated into a plurality of unit regions corresponding to the plurality of light-emitting parts  30 U. 
     The plurality of light-emitting parts  30 U are, for example, aligned in a two dimensional array along the x-axis direction and the y-axis direction, and the arrangement pitch along the x-axis direction is equal to the arrangement pitch along the y-axis direction. The alignment directions of the light-emitting parts  30 U can be appropriately determined. The arrangement pitch in the x-axis direction and the y-axis direction can be different, and the two directions of the alignment do not have to be orthogonal. Also, the arrangement pitch can be uneven other than equal spacing. 
     It is preferable that the number of the light-emitting parts  30 U, i.e., the number of demarcations of the light-emitting surface  30   a  is, for example, 16 or greater. This allows more precise control of the luminance distribution on the light-emitting surface  30   a . Meanwhile, when the number of the light-emitting parts  30 U is 15 or less, the need for an increase in the size of the light source  30  can be reduced. 
     When the light source device  200  is applied to a camera&#39;s flashlight, the light-emitting surface  30   a  can be demarcated in view of an aspect ratio of an image. When the aspect ratio is 4:3, the light-emitting surface  30   a  can be demarcated with a total of 63 light-emitting parts  30 U aligned 9 parts in the x-axis direction and 7 parts in the y-axis direction (represented as “9×7”), or can be demarcated with 7×5, a total of 35 light-emitting parts  30 U. 
     In the example shown in the figures, the light source  30  includes a total of 63 of the light-emitting parts  30 U arranged in a matrix of 9×7. For example, the light-emitting surface  30   a  of the light source  30  has a length LX of 3.12 mm along the x-axis direction and a length LY of 2.46 mm along the y-axis direction. The arrangement pitches Px and Py in the x-axis direction and the y-axis direction respectively, of the light-emitting parts  30 U are, for example, 330 μm. The thickness (length along the z-axis direction) of the light source  30  is, for example, 230 μm. 
     The plurality of light-emitting parts  30 U can be operated independently of each other. This allows only the selected light-emitting part(s) out of the plurality of light-emitting parts  30 U to be caused to emit light and the other light-emitting parts not to emit light (partial drive). By partially driving the plurality of light-emitting parts  30 U, it is possible to irradiate (project) light with a predetermined intensity distribution. Accordingly, for example, when using the light source device  200  of the present embodiment as a flashlight of a camera, the luminance distribution of the irradiating light is controlled according to the information of the area of the light being illuminated (position and distance of the subject, etc.), thereby reducing black crushing and halation, allowing to capture sharper photos. 
     Depending on the application of the light source device, some or all of the plurality of light-emitting parts  30 U can be operated in a state of continuously emitting light. 
     For the light source  30 , any appropriate surface light-emitting light source known in the art can be used. Preferably, the light source  30  has a structure in which a plurality of light-emitting elements  50 , such as light-emitting diodes, are arranged in a two dimensional array. The plurality of light-emitting elements  50  are arranged corresponding to the plurality of light-emitting parts  30 U. Each of the plurality of light-emitting parts  30 U includes one or more corresponding light-emitting elements among the plurality of light-emitting elements  50 . By individually causing one or more of the light-emitting elements  50  to emit light in each light-emitting part  30 U, a partial drive of the light-emitting parts  30 U can be achieved, and the intensity distribution in the light-emitting surface  30   a  can be controlled. 
     In the present embodiment, the light source  30  includes a plurality of light-emitting elements  50 , a plurality of wavelength converting layers  60 , a plurality of light-diffusing layers  70 , and a light-reflecting member  80 . Each component of the light source  30  will be described below. 
     Light-Emitting Element  50   
     The plurality of light-emitting elements  50  are arranged in a two dimensional array in a plan view. In the present embodiment, each of the light-emitting parts  30 U has a corresponding one of the light-emitting elements  50 . Two or more light-emitting elements  50  can be disposed to each of the light-emitting parts  30 U. 
     In the example shown in the figures, a plurality ( 63  in the example) of light-emitting elements  50  are aligned in two directions perpendicular to each other, i.e., in the x-axis direction and the y-axis direction, and are spaced apart from each other. The “arrangement pitch” of the light-emitting elements  50  refers to a distance between centers of two adjacent light-emitting elements in a plan view. In this example, the arrangement pitches of the light-emitting elements  50  is the same as the arrangement pitches Px and Py, for example, 330 μm, of the light-emitting parts described above. 
     The arrangement pitches of the light-emitting elements  50  in the x-axis direction and in the y-axis direction can be the same or different, or the two directions of the arrangement do not have to be orthogonal. Also, the arrangement pitches can be in equal spacing or in uneven spacing. For example, the plurality of light-emitting elements  50  can be arranged with increasing distance to adjacent light-emitting elements  50  from the center toward the periphery of the substrate  40 . 
       FIG.  5 C  shows an enlarged cross-sectional view showing a portion of the light source  30 , in which a portion illustrated includes three light-emitting elements of the plurality of light-emitting elements  50 . 
     As shown in  FIG.  5 C , each light-emitting element  50  includes a light emission surface  50   a  from which light is mainly extracted, an electrode forming surface  50   b  located opposite side from the light emission surface  50   a , and lateral surfaces  50   c  located between the light emission surface  50   a  and the electrode forming surface  50   b , and at least has a positive and a negative electrodes  51  on the electrode forming surface  50   b . The electrodes  51  are electrically connected to respective portions of the wirings  42  exposed on the substrate  40 . For example, a wavelength converting layer  60  is disposed on the light emission surface  50   a  of each of the light-emitting elements  50 . 
     For the light-emitting element  50 , various types of light-emitting elements such as a semiconductor laser element, a light-emitting diode, or the like can be employed. In the present embodiment, a light-emitting diode is employed as a light-emitting element  50 . The wavelength of the light emitted by the light-emitting element  50  can be appropriately determined. For example, a light-emitting element configured to emit light of a blue color or a green color, a light-emitting element having a nitride-based semiconductor (In x Al y Ga 1-x-y N, 0≤x, 0≤y, x+y≤1), ZnSe, or GaP can be employed. For example, for a red-light-emitting element, a light-emitting element having a semiconductor such as GaAlAs, AlInGaP, or the like can be employed. Semiconductor light-emitting elements made of materials other than those described above can also be used. The composition, the color of emitting light, the size and the number of the light-emitting elements to be employed can be selected appropriately. The light-emitting layer of the light-emitting element  50  preferably includes a nitride-based semiconductor (In x Al y Ga 1-x-y N, 0≤x, 0≤y, x+y≤1) configured to emit light having a short-wavelength that can efficiently excite a wavelength converting material contained in the wavelength converting layer  60 . The emission wavelength can be variously set by the materials and/or mixed crystal ratio of the semiconductor layer. The positive and negative electrodes can be disposed on the same side, or the positive and negative electrodes can be disposed on different surfaces. 
     The light-emitting element  50  includes, for example, a light-transmissive substrate such as sapphire, and a semiconductor layered structure layered on the light-transmissive substrate. The semiconductor layered structure includes a light-emitting layer, an n-type semiconductor layer, and a p-type semiconductor layer, the light-emitting layer being located between the n-type and the p-type semiconductor layers. A positive electrode is electrically connected to the n-type semiconductor layer and a negative electrode is electrically connected to the p-type semiconductor layer. The lower surfaces of the positive and negative electrodes  51  are respectively electrically connected to corresponding wirings  42  provided to the substrate  40 . 
     The electrodes  51  are formed of a known metal material that can be electrically connected to the semiconductor layered structure. Examples of the material of the electrodes  51  include metal such as Ni, Pt, Cu, Au, Ag, and AuSn. Preferably Cu is used. The electrodes  51  can have a single layer structure or a layered structure. A terminal protective film can be formed to cover the electrodes  51 . For example, as the terminal protective film, a Ni film (thickness: e.g., 5 nm) may be formed on the surface of the electrodes  51  made of Cu, and an Au film (thickness: e.g., 25 nm) may be formed on the Ni film. 
     The light-emitting elements  50  have a rectangular shape in a plan view, for example. The size of the light-emitting elements  50  can be appropriately determined. Each of the light-emitting elements  50  has a longitudinal length and a lateral length of, for example, 1,000 μm or less, preferably 500 μm or less, further preferably 300 μm or less. With this size of light-emitting elements  50 , it is possible to increase the number of demarcations of the light-emitting surface  30   a  while reliably obtaining the light intensity of each of the light-emitting elements  50 . Therefore, when the light source  30  is partially driven, a sufficient light-dark contrast can be created with a smaller unit in the irradiated area. 
     In the present embodiment, each of the light-emitting elements  50  has a square shape with a side of 220 μm. In each of the light-emitting elements  50 , the light-transmissive substrate and the semiconductor layered structure have a thickness of, for example, 120 μm, and the electrodes  51  have a thickness of, for example, 40 μm. The arrangement pitches of the light-emitting elements  50  in the x-axis direction and the y-axis direction are, for example, 330 μm, as described above. 
     Wavelength Converting Layer  60   
     The wavelength converting layer  60  is located above the light emission surface  50   a  of each of the light-emitting elements  50  (in the +z direction) and covers the light emission surface  50   a  of the light-emitting element  50 . The wavelength converting layer  60  absorbs at least a portion of the light emitted from the light-emitting element  50  and emit light of a different wavelength. 
     The wavelength converting layer  60  has an upper surface  60   a , a lower surface  60   b  located opposite side from the upper surface  60   a  and facing the light-emitting element  50 . The lower surface  60   b  of the wavelength converting layer  60 , can be bonded or adhered to the light emission surface  50   a  of the light-emitting element  50 . 
     The wavelength converting layer  60  can have an approximately rectangular shape in a plan view. It is preferable that the wavelength converting layer  60  is larger than the light emission surface  50   a  of the light-emitting element  50  and covers the entire light emission surface  50   a . With this arrangement, light emitted from the light-emitting element  50  can be efficiently incident on the wavelength converting layer  60 , facilitating emission of wavelength-converted light from the wavelength converting layer  60  can be obtained. Further, it is possible to reduce a decrease in brightness at portions of the light-emitting surface  30   a  corresponding to the portions between the light-emitting elements. 
     In the present embodiment, the wavelength converting layer  60  has, for example, a square shape in a plan view, with a side of 305 μm. The wavelength converting layer  60  has a thickness of, for example, 40 μm in the z-axis direction. 
     In the present embodiment, the wavelength converting layer  60  is provided for each of the light-emitting elements  50 , but a single wavelength converting layer common to the plurality of light-emitting elements  50  can be provided. 
     The wavelength converting layer  60  includes, for example, a resin as a base material, and a wavelength converting material dispersed in the resin. Examples of the base material include light-transmissive materials such as epoxy resin, silicone resin, resins that are mixtures of those, and glass. In view of light-resisting properties and ease of molding, silicone resin is preferably be selected for the base material of the wavelength converting layer  60 . In particular, it is preferable to use phenyl silicone resin as a main component of the base material. The wavelength converting layer  60  having ceramic or glass as the main material and containing a wavelength converting material can be employed. 
     The wavelength converting material is configured to be excited by light emitted from the light-emitting element  50  and emit light having a wavelength different from that of light emitted from the light-emitting element  50 . Examples of the wavelength converting material include yttrium aluminum garnet (YAG)-based fluorescent materials activated with cerium (for example, Y 3 (Al, Ga) 5 O 12 :Ce), lutetium aluminum garnet (LAG)-based fluorescent materials activated with cerium (for example, Lu 3 (Al, Ga) 5 O 12 :Ce), terbium aluminum garnet-based fluorescent materials (for example, Tb 3 (Al, Ga) 5 O 12 : Ce), nitrogen-containing calcium aluminosilicate (CaO—Al 2 O 3 —SiO 2 )-based fluorescent materials activated with europium and/or chromium, silicate ((Sr, Ba) 2 SiO 4 )-based fluorescent materials activated with europium, β-sialon fluorescent materials (for example, (Si, Al) 3 (O, N) 4 :Eu), α-sialon fluorescent materials (for example, M z (Si, Al) 12 (O, N) 16  (in which 0&lt;Z≤2, M is at least one element selected from the group consisting of Li, Mg, Ca, Y, and lanthanoid elements except for La and Ce), nitride-based fluorescent materials such as CASN-based fluorescent materials (for example, CaAlSiN 3 :Eu) or SCASN-based fluorescent materials (for example, (Sr, Ca) AlSiN 3 :Eu), fluoride-based fluorescent materials such as KSF-based fluorescent materials (for example, K 2 SiF 6 :Mn 4+ ) or MGF-based fluorescent materials (for example, 3.5 MgO.0.5 MgF 2 .GeO 2 :Mn), sulfide-based fluorescent materials, perovskite, chalcopyrite, and quantum dots. Fluorescent materials other than those shown above that can exert similar performance, action, and/or effect can also be employed. The wavelength converting layer  60  containing one wavelength converting material of one of the types of wavelength converting substances shown above can be employed, but the wavelength converting layer  60  containing two or more types of wavelength converting substances is preferable. For example, the wavelength converting layer  60  preferably contain an LAG-based fluorescent material configured to produce light in green region, and a CASN-based fluorescent material configured to produce light in red region. Accordingly, the light source  30  to emit a white light can be realized. Further, the inclusion of two or more types of wavelength converting materials can broaden the wavelength band and reduce generation of wavelength regions with weak luminance intensity. The content of a wavelength converting material (fluorescent material) in the wavelength converting layer  60  can be, for example, in a range of 10 to 80 weight %. In the present specification, the term “weight %” refers to a ratio of the weight of the contained substance(s) to a total weight that includes the weight of the base material and the weight of the contained substance(s) (in this case, the wavelength converting material(s)). 
     The wavelength converting material can be disposed in the wavelength converting layer  60  in any appropriate manner. For example, the wavelength converting material can be distributed evenly within the wavelength converting layer  60 , or can be distributed in only a portion of the wavelength converting layer  60 . The expression “distributed in a portion of the wavelength converting layer  60 ” includes, for example, a distribution of a wavelength converting material with its concentration higher in a portion near the upper surface  60   a  or the lower surface  60   b  in the wavelength converting layer  60 . Or, in a plan view, a distribution of a wavelength converting material with its concentration higher near the center or periphery of the wavelength converting layer  60 . The wavelength converting layer  60  can be formed by layering a plurality of layers, each containing a wavelength converting substance. 
     The wavelength converting layer  60  can also include a material other than the wavelength converting material(s). For example, a material having a refractive index different than a refractive index of the base material can be dispersed in the wavelength converting layer  60 . For example, light-diffusing particles such as titanium oxide or silicon oxide can be dispersed in the base material of the wavelength converting layer  60 . 
     Light-Diffusing Layer  70   
     The light-diffusing layer  70  is disposed over (in the +z direction) the wavelength converting layer  60 . The light-diffusing layer  70  is configured to diffuse the light emitted from the light-emitting element(s)  50 . 
     The light-diffusing layer  70  includes an upper surface  70   a  and a lower surface  70   b  is located on the  60  side of the wavelength converting layer of the upper surface  70   a . In the present embodiment, the upper surface  70   a  of the light-diffusing layer  70  corresponds to the upper surface of the light source  30  and serves as the light-emitting surface  30  of the light source  30 . 
     The light-diffusing layer  70  can have an approximately rectangular shape in a plan view. It is preferable that the light-diffusing layer  70  is larger than the light emission surface  50   a  of a corresponding one of the light-emitting elements  50  and entirely covers the light emission surface  50   a  in a plan view. The size of the light-diffusing layer  70  can be approximately the same as the size of the wavelength converting layer  60 . The light source  30  tends to experience luminance unevenness: brighter regions over the light emission surface  50   a  of each of the light-emitting elements  50 , and darker regions over the portions between the light emission surfaces  50   a  of adjacent two light-emitting elements  50  (in the example shown in the figures, a light-reflecting member  80  is disposed corresponding to the (darker) regions). There is also a concern that when blue light-emitting elements  50  are used in a white light emitting light source  30 , the emission may be viewed as blue glow from the light emission surfaces  50   a  while yellow light leaking from a region between two adjacent light emission surfaces  50   a  (color unevenness). By arranging the light-diffusing layer  70  above the wavelength converting layer  60  (in the +z direction), the light emitted from the light emission surface  50   a  of the light-emitting element  50  can be diffused to suppress such luminance and color variations. 
     In the present embodiment, the light-diffusing layer  70  has, for example, a square shape in a plan view with a side of 305 μm. The thickness of the light-diffusing layer  70  in the z-axis direction is, for example, 30 μm. 
     In the present embodiment, the light-diffusing layer  70  is provided for each of the light-emitting elements  50 , but it is possible to provide a single light-diffusing layer  70  common to the plurality of light-emitting elements  50 . When a common light-diffusing layer  70  is provided for the plurality of light-emitting elements  50 , the light-diffusing layer  70  may have uneven thickness in the z-axis direction. As shown in  FIG.  11   , for example, portions of the light-diffusing layer  70  located between the adjacent light-emitting elements  50  in a plan view may have a thickness smaller than a thickness of portions overlap with the light-emitting elements  50 . In other words, it is possible to provide grooves  71  in the lower surface  70   b  of the light-diffusing layer  70  at locations between adjacent light-emitting elements  50 . The light-diffusing layer  70  has a thickness in the z-axis direction (i.e., a thickness between the upper surface  70   a  to the lower surface  70   b  of the light-diffusing layer  70 ) of, for example, 30 μm, and a depth of the grooves  71  in the z-axis direction (i.e. a depth of the grooves from the lower surface  70   b  of the light-diffusing layer  70 ) is greater than 0 μm, for example, less than ⅔ of the thickness of the light-diffusing layer  70  in the z-axis direction. 
     The light-diffusing layer  70  contains a resin serves as a base material and a light-diffusing material dispersed in the resin. Examples of the base material include light-transmissive materials such as epoxy resin, silicone resin, resins that are mixtures of those, and glass. In view of light-resisting properties and ease of molding, it is preferable to employ silicone resin as the base material of the light-diffusing layer  70 . In particular, it is preferable to use phenyl silicone resin as a main component of the base material. In addition, by using the same resin as the wavelength converting layer  60  as the base material of the light-diffusing layer  70 , adhesion between the wavelength converting layer  60  and the light-diffusing layer  70  can be improved. The light-diffusing layer  70  can be made of ceramic or glass as its main material in which a light-diffusing material is contained. 
     The light-diffusing materials have high light reflectance, examples thereof include white fillers such as titanium oxide, silicon oxide, alumina, and zinc oxide. The content of the light-diffusing material in the light-diffusing layer  70  is preferably in a range of 0.1 to 3.0 mass %. The light-diffusing layer  70  can contain glass filler, etc., to reduce or prevent expansion and contraction caused by the heat generated in the resin of the base material. The content of glass filler in the light-diffusing layer  70  is preferably in a range of 50 to 80 mass %. Other than those, the content of the light-diffusing material, glass filler, etc. can be appropriately determined. The light-diffusing layer  70  preferably contains titanium oxide and glass filler. 
     Light-Reflecting Member  80   
     The light-reflecting member  80  is disposed on the first surface  40   a  of the substrate  40 , and covers the first surface  40   a  of the substrate  40  and the lateral surfaces  50   c  of the plurality of light-emitting elements  50 . The light-reflecting member  80  can further cover the lateral surfaces of the wavelength converting layer  60  and the lateral surfaces of the light-diffusing layer  70 . In addition, the light-reflecting member  80  can be disposed covering the lateral surfaces of the electrodes  51  and filling the gap between the electrode forming surface  50   b  of the plurality of light-emitting elements  50  and the first surface  40   a  of the substrate  40 . Alternatively, an underfill resin can be filled in gaps between the electrode forming surfaces  50   b  of the light-emitting elements  50  and the first surface  40   a  of the substrate  40 . With the underfill resin, stress caused by a difference in the coefficient of thermal expansion between the light-emitting elements  50  and the substrate  40  can be reduced, or heat dissipation can be increased. 
     The light-reflecting member  80  exposes the lower surface of the electrodes  51  of each light-emitting element  50  and the upper surface  70   a  of each light-diffusing layer  70 . The lower surfaces of the electrodes  51  are electrically connected to wirings  42  of the substrate  40 , respectively. When the light-diffusing layer  70  is not provided, the upper surface  60   a  of the wavelength converting layer  60  can serve as the light-emitting surface  30   a  of the light source  30 . 
     By arranging the light-reflecting member  80  between the light-emitting parts  30 U, propagation of light between the light-emitting parts  30 U can be reduced or prevented, and accordingly can reduce the uneven color. Further, when the partial drive described above is performed, the contrast between the light-emitting parts  30 U in operation and the light-emitting part  30 U not in operation can be improved. 
     In the present embodiment, the light-reflecting member  80  seals the plurality of light-emitting elements  50  and holds them together. The light-reflecting member  80  can be separately disposed corresponding to each of the light-emitting elements  50 . 
     The light-reflecting member  80  protects the plurality of light-emitting elements  50 . Also, the light-reflecting member  80  reflects the light emitted from the lateral surfaces  50   c  of corresponding one or more of the light-emitting elements  50  and directs the light upwards (in the +z direction) of the light-emitting element(s)  50 . Further, by disposing the light-reflecting member  80  also between the electrode forming surfaces  50   b  of the light-emitting elements  50  and the substrate  40 , the light propagating from the electrode forming surfaces  50   b  of the light-emitting elements  50  toward the substrate  40  can be reflected by the light-reflecting member  80  and is directed upward (in the +z direction) of the light-emitting elements  50 . Accordingly, utilization efficiency of light emitted from each of one or more light-emitting elements  50  can be improved. 
     The light-reflecting member  80  includes, for example, a resin that serves as the base material and a light-reflecting material dispersed in the resin. Examples of the base material include light-transmissive materials such as epoxy resin, silicone resin, resins that are mixtures of those, and glass. In view of light-resisting properties and ease of molding, silicone resin is preferably employed for the base material of the light-reflecting member  80 . In particular, dimethyl silicone resin or phenyl silicone resin is preferably employed as a main composition of the base material. Further, by using the same resin as the wavelength converting layer  60  and the light-diffusing layer  70  for the base material of the light-reflecting member  80 , adhesion to the wavelength converting layer  60  and to the light-diffusing layer  70  can be improved. 
     Examples of the light-reflecting materials include titanium oxide, silicon oxide, zirconium oxide, yttrium oxide, yttria-stabilized zirconia, potassium titanate, alumina, aluminum nitride, boron nitride, and mullite. This allows for more effective reduction of light leakage in the +/−x direction, +/−y direction and −z direction of each light-emitting part  30 U. The content of the light-reflecting material and other materials in the light-reflecting member  80  is preferably in a range of 10 to 70 mass %. In addition, the light-reflecting member  80  can contain glass filler, etc. to reduce or prevent expansion and contraction caused by the heat of the resin in the base material. The content of the glass filler is preferably in a range of 0 to 30 mass %, more preferably in a range of 5 to 20 mass %. Other than illustrated above, the content of the light-reflective material, glass filler, etc. can be appropriately determined. The light-reflecting member  80  preferably contains titanium oxide and glass filler. 
     3. Substrate  40   
     The light source  30  including the plurality of light-emitting elements  50  is disposed on the substrate  40 . The substrate  40  includes a first surface  40   a  and a second surface  40   b  located opposite side from the first surface  40   a.    
     In the example shown in  FIG.  5 C , the substrate  40  has a plate-shaped base  41 , wirings  42  disposed on the first surface  40   a  of the base  41 , and external terminals  43  disposed on the second surface  40   b  of the base  41 . The first surface  40   a  of the base  41  can serve as the first surface  40   a  of the substrate  40 , and the second surface  40   b  of the base  41  can serve as the second surface  40   b  of the substrate  40 . The wirings  42  are electrically connected to the respective electrodes  51  of a corresponding one of the light-emitting elements  50 . The wirings  42  are electrically connected to the external terminals  43  via, for example, beer holes and via conductors provided to the base  41 . 
     Examples of the material of the base  41  include insulating materials such as glass epoxy, resin, and ceramics, metal member having surfaces covered by an insulating material. Of those, a ceramic that has high heat resistant property and high weather resistant property can be preferably used for the material of the base  41 . Examples of the ceramics material include alumina, aluminum nitride, mullite. Such a ceramics material can be used in combination with an insulating material such as a bismaleimide triazine resin (BT resin), a glass epoxy, an epoxy-based resin, or the like. 
     The wirings  42  and the external terminals  43  can be made of, for example, one or more metals such as Cu, Al, Au Ag, Pt, Ti, W, Pd, Fe, and Ni, or an alloy containing one or more such metals. 
     The substrate  40  can be a substrate having wirings (wiring substrate), which allows for mounting of light-emitting elements such as LEDs and various electric elements. A wiring substrate can be formed with a wiring pattern, allowing for more complex wirings, which is necessary for the drive (partial drive) of the plurality of light-emitting parts  30 U to emit light independently of each other. 
     Method of Manufacturing Lens Structure  100   
     One example of a method of manufacturing the lens structure  100  using a double-shot molding technique will be illustrated below with reference to the drawings. 
     In the present embodiment, a lens is molded as a primary molded article, and a support part is molded as a secondary molded article. In molding a lens, that is a primary molded article, a lower mold corresponding to a lower surface of the lens (hereinafter referred to as “common mold”), and an upper mold corresponding to an upper surface of the lens (hereinafter referred to as “primary mold.” The common mold is used in common when molding the primary molded article and when molding the secondary molded article. In molding a support part, that is a secondary molded article, the common mold and a mold having a different shape than the primary mold (hereinafter referred to as “secondary mold”). 
       FIG.  6 A  to  FIG.  6 E  are schematic cross-sectional views, illustrating steps of a method of manufacturing the lens structure  100 . 
     As shown in  FIG.  6 A , a common mold  110  having a fifth surface  110   a  and a primary mold  120  having a sixth surface  120   a  are provided. 
     The fifth surface  110   a  of the common mold  110  is the surface to form the lower surface of the lens, and the fifth surface  110   a  includes surfaces corresponding to the second surface of the optically functional part and the fourth surface of the flange part. The fifth surface  110   a  includes at least one protruding portion  112  to form the at least one first recess of the flange part. The sixth surface  120   a  of the primary mold  120  is the surface to form the upper surface and the lateral surfaces of the lens, and the sixth surface  120   a  includes surfaces corresponding to the third surface of the flange part and the outer lateral surfaces of the flange part. 
     The common mold  110  and the primary mold  120  are held such that the fifth surface  110   a  of the common mold  110  and the sixth surface  120   a  of the primary mold  120  are held to face each other (clamping). This forms a first cavity  121  between the common mold  110  and the primary mold  120 . The first cavity  121  is the space used to form the lens that is the primary molded article. 
     Then, as shown in  FIG.  6 B , the lens  10  is molded as the primary molding article (primary molding step). A first resin is injected into the first cavity  121  from a first resin injection port  122 , which is formed in the primary mold  120  at a location to form the flange part of the lens. For the first resin, for example, a thermoplastic transparent resin material with polycarbonate as the base material is used. Then, the first resin in the first cavity  121  is cooled and solidified. When a thermosetting resin is used as the first resin, the first resin is cured by heating. With this, the lens  10  is formed with the first resin. The lens  10  has an optically functional part  11  and a flange part  12 . On the lower surface of the flange part  12 , the at least one first recess  13  corresponding to the surface shape of the at least one protruding portion  112  of the common mold  110  is formed. 
     A step of first mold opening process is then performed by moving one of the common mold  110  and primary mold  120  away from the other, as shown in  FIG.  6 C . In this case, as illustrated, the lens  10  that is the primary molded article is demolded from the primary mold  120  and remains on the common mold  110 . In the present embodiment, because the at least one first recess  13  is formed in the lower surface  10   b  of the lens  10 , a contact area between the lower surface  10   b  of the lens  10  and the fifth surface  110   a  of the common mold  110  is greater, compared to a case in which the at least one first recess  13  is not provided in the lower surface  10   b  of the lens  10 , allowing higher adhesion between the lens  10  and the common mold  110 . Therefore, the lens  10  can be demolded from the primary mold  120  while the lens  10  is held on the common mold  110 . 
     Then, as shown in  FIG.  6 D , a secondary mold  130  having a seventh surface  130   a  is provided. The secondary mold  130  is placed on the common mold  110 , which holds the lens  10 , and the mold is clamped. This creates a second cavity  131  between the common mold  110 , the lens  10 , and the secondary mold  130 . The second cavity  131  is the space used to form the support part that is the secondary molded article. A portion of the upper surface  10   a  of the lens  10  is in contact with a seventh surface  130   a  of the secondary mold  130 . In the example shown in the figure, the space between the edge portion of the first surface  11   a  of the optically functional part  11  of the lens  10 , the third surface  12   a  and the outer lateral surfaces  12   c  of the flange part  12 , the seventh surface  130   a  of the secondary mold  130 , and the lateral surfaces  110   b  of the common mold  110  create the second cavity  131 . 
     Subsequently, as shown in  FIG.  6 E , the support part  20  is molded as the secondary molded article (a step of secondary molding). A second resin is injected into the second cavity  131  from a second resin injection port  132 , which is formed in the secondary mold  130  at a location to form the first flange portion of the support part  20 . For the second resin, for example, a dark-colored thermoplastic resin material is used as the second resin. Then, the second resin in the second cavity  131  is cooled and solidified. When a thermosetting resin is used as the second resin, the second resin is cured by heating. With this, the support part  20  is formed with the second resin. The support part  20  and the lens  10  are solidly joined by the contacting of the support part  20  with the edge portion of the first surface  11   a  of the optically functional part  11  of the lens  10 , the third surface  12   a  and the outer lateral surfaces  12   c  of the flange part  12 . As described above, the lens structure  100  can be obtained. In  FIG.  6 D  and  FIG.  6 E , the second resin injection port  132  is formed in the secondary mold  130  at the location to form the first flange portion of the support part  20 , but the second resin injection port  132  can be formed at an appropriate location. For example, the second resin injection port  132  can be formed in the secondary mold  130  at a location to form the second hood portion. 
     The support part  20  is in contact with at least a portion of the upper surface  10   a  of the lens  10 . As shown in the figure, the support part  20  can cover the outer lateral surfaces of the lens  10  (i.e. the outer lateral surfaces  12   c  of the flange part  12 ). In the present embodiment, the support part  20  is molded while the lower surface  10   b  of the lens  10  is in contact with the common mold  110 , such that the support part  20  and the lower surface  10   b  of the lens  10  are not in contact with each other. 
     Subsequently, the secondary mold  130  and the common mold  110  is opened (hereinafter referred to as “a step of second mold opening”). Thus, the lens structure  100  is separated from the secondary mold  130  while held on the common mold  110 . The lens structure  100  is then removed from the common mold  110  by demolding the lens structure  100  from the common mold  110 . In the present embodiment, as described above, the first hood portion  21  and the second hood portion  22  of the support part  20  inclined toward the optical axis of the lens  10  along the +z direction, and the first hood portion  21  has a tapered shape in the +z direction, which can facilitate opening of the secondary mold  130  and the common mold  110 . 
     In the present embodiment, after the lens  10  is molded as the primary molded article, the support part  20  is molded as the secondary molded article. If the support part  20  is molded (the support part  20  is the primary molded article) before molding the lens  10  (the lens  10  is the secondary molded article), because of the presence of the support part  20 , the resin material of the lens cannot be injected from the lateral surface of the mold. If the resin material is injected from a location other than a lateral surface of the mold, the resin injection port is needed to be located in a region of the optically functional part  11  of the lens  10 , which may affect the optical action of the optically functional part  11 . Therefore, it is preferable to form lens  10  in the step of primary molding and to form the support part  20  in the step of secondary molding. 
     When manufacturing a lens structure using a conventional double-shot molding technique, if a contact area between the upper surface of the lens and the upper mold is greater than a contact area between the lower surface of the lens and the lower mold, the lower surface of the lens may be separated from the lower mold, resulting in the lens retained in the upper mold. In contrast, according to the present embodiment, forming the at least one first recess  13  in the lower surface  10   b  of the lend  10  increase a contact area between the lens  10  and the common mold  110 , such that adhesion between the lower surface  10   b  of the lens  10  and the fifth surface  110   a  of the common mold  110  can be improved. Therefore, occurrence of retention of the molded product in the primary mold in the step of first mold opening can be reduced or prevented, and the primary mold  120  and lens  10  can be more easily separated. As a result, the support part  20  that is the secondary molded article, can be molded continuously on the lens  10  after the step of first mold opening. According to the present embodiment, the molding of the lens structure  100  does not require the use of complex molds, and with the use of only three types of molds: common mold  110 , primary mold  120 , and secondary mold  130 , occurrence of retention of the molded article in a mold can be reduced or prevented. 
     The adhesion between the lens  10  and the common mold  110  can be adjusted by the contact area between the lower surface  10   b  of the lens  10  and the fifth surface  110   a  of the common mold  110 , and in addition thereto, the shape of the at least one first recess  13  in a plan view, the inclination angles of the lateral surfaces defining the at least one first recess  13 , the location and the number of the first recesses, etc. 
     Variational Examples 
     Variational examples of the lens according to the present disclosure will be described below. Each of the lenses of the variational examples is formed with a protrusion or a second recess in a lateral surface defining each of the first recesses, which differs from the lens shown in  FIG.  3 A  and  FIG.  3 B . In the description below, differences from the first recess shown in  FIG.  3 A  and  FIG.  3 B  will be mainly illustrated, and repetitive description of the similar structure will be appropriately omitted. In each drawing showing variational examples, components similar to those shown in  FIG.  3 A  and  FIG.  3 B  are indicated with the same reference characters for clarity. 
     In Variational Examples 1 to 4, the first recess defined in a circular groove in a plan view will be illustrated. But other than a circular shape, the shape of to the first recess in a plan view can be appropriately defined. 
       FIG.  7 A  is a schematic enlarged plan view of a portion of the flange part  12  of the lens  10  of Variational Example 1, and  FIG.  7 B  is a schematic enlarged cross-sectional view taken along line  7 B- 7 B of  FIG.  7 A .  FIG.  8 A  is a schematic enlarged view of a portion of the flange part  12  of the lens  10  of Variational Example 2, and  FIG.  8 B  is a schematic enlarged cross-sectional view taken along line  8 B- 8 B of  FIG.  8 A . 
     As shown in the figures, the lateral surfaces defining the first recess  13  include a first lateral surface  13   s   1  along the outer periphery of the optically functional part, and a second lateral surface  13   s   2  facing the first lateral surface  13   s   1  and is located closer to the optically functional part than the first lateral surface  13   s   1  to the optically functional part. 
     In Variational Example 1, the first recess  13  is formed with one second recess  14  formed in the first lateral surface  13   s   1  and extending along the first lateral surface  13   s   1 . Providing the second recess  14  allows for more effective adhesion between the lower surface of lens  10  and the common mold during the step of first mold opening. The second recess  14  can, for example, extend along the entire length of the first lateral surface  13   s   1 , to surround the optically functional part in a plan view. The formation of the second recess  14  along the entire circumference of the first lateral surface  13   s   1  can facilitate efficient reduction or prevention of the occurrence of retention of the lens  10 . 
     In Variational Example 2, a plurality of second recesses  14  are formed in the first lateral surface  13   s   1 . The plurality of second recess  14  are arranged spaced apart from each other in a plan view. For example, as shown in Variational Example 1, when one circular ring-shaped second recess  14  extending along the first lateral surface  13   s   1  in a plan view is formed in the first lateral surface  13   s   1 , an excess degree of adhesion may result between the lower surface of the lens  10  and the common mold depending on the material(s) of the lens  10 . In such a case, the degree of adhesion can be adjusted by selecting the size, the number, and the arrangement pitch of the second recesses  14 . This allows easy separation of the lens structure  100  from the common mold  110  after the step of second molding, while reducing or preventing the occurrence of retention in the mold in the step of first mold opening. 
     In Variational Example 1 and Variational Example 2, the depth of the second recesses  14  (i.e., a maximum width in the x-y plane) w 3  is, for example, preferably in a range of ⅓ to ½ of the width w 2  of the first recess  13 , for example, 0.1 mm. The length d 3  of the second recess  14  in the z-axis direction is, for example, in a range of ⅓ to ⅔ of the depth d 2  of the first recess  13 , for example, 0.2 mm. 
       FIG.  9 A  is a schematic enlarged plan view of a portion of the flange part  12  of the lens  10  of Variational Example 3, and  FIG.  9 B  is a schematic enlarged cross-sectional view taken along line  9 B- 9 B of  FIG.  9 A .  FIG.  10 A  is a schematic enlarged plan view of a portion of the flange part  12  of the lens  10  of Variational Example 4, and  FIG.  10 B  is a schematic enlarged cross-sectional view taken along line  10 B- 10 B of  FIG.  10 A . 
     In Variational Example 3, the first recess  13  is formed with a protrusion  15  extending along the first lateral surface  13   s   1 . This makes it possible to more efficiently increase the adhesion between the lower surface of the lens  10  and the common mold during the step of mold opening. The protrusion  15  can be, for example, extended along the entire length of the first lateral surface  13   s   1  surrounding the optically functional part in a plan view. Forming the protrusion  15  along the entire circumference of the first lateral surface  13   s   1  can be more effective in reducing or preventing occurrence of retention in the mold. 
     In Variational Example 4, the first recess  13  is formed with a plurality of protrusions  15  on the first lateral surface  13   s   1 . The plurality of protrusions  15  are arranged spaced apart from one another in a plan view. For example, as shown in Variational Example 3, when one circular protrusion  15  extending along the first lateral surface  13   s   1  in a plan view is formed on the first lateral surface  13   s   1 , an excess degree of adhesion between the lower surface of the lens  10  and the common mold may results depending on the material(s) of the lens  10 . In such a case, the degree of adhesion between the lower surface of the lens  10  and the common mold can be adjusted by selecting the size, the number, and the arrangement pitch etc., of the protrusion  15 . This allows easy separation of the lens structure  100  from the common mold  110  after the step of second molding, while reducing or preventing occurrence of retention in the mold in the step of first mold opening. 
     In Variational Example 3 and Variational Example 4, the height of the protrusion  15  (i.e. the maximum width in the x-y plane) w 4  is, for example, preferably in a range of ⅓ to ½ of the width w 2  of the first recess  13 , e.g. 0.1 mm. The length d 4  of the protrusion  15  in the z-axis direction is, for example, preferably in a range of ⅓ to ⅔ of the depth d 2  of the first recess  13 , for example 0.2 mm. 
     The second recess  14  or the protrusion  15  preferably has a rounded shape in a cross-sectional view. With this arrangement, demolding of the double-shot molded article (lens structure  100 ) from the common mold after the step of secondary molding can be facilitated. As a result, occurrence of deformation or the like of the secondary molded article in demolding can be reduced or prevented. 
     Other than that illustrated in the figures, the size, number, and shape of the second recess  14  or the protrusion  15  formed in the first recess  13  can be appropriately determined. The cross-sectional shape of the second recess  14  and the protrusion  15  in the x-y plane can be a rectangular shape. Both the protrusion and the second recess can be formed in a single first recess  13 . 
     In Variational Example 1 to 4, the one or more second recesses  14  or the one or more protrusions  15  are formed in or on the first lateral surface  13   s   1  that is located farther from the optically functional part  11  of the first lateral surface  13   s   1  and the second lateral surface  13   s   2  of the first recess  13 . This arrangement can further reliably reduce or prevent the effect of the second recess  14  or the protrusion  15  on the optical action of the optically functional part  11 . 
     It is also desirable that the one or more second recesses  14  or the one or more protrusions  15  are located on the first lateral surface  13   s   1  of the first recess  13 . In the present embodiment, forming the one or more first recesses  13  in the flange part  12  allows a portion of the flange part  12  located closer to the outer lateral surface than the first recess  13  to the outer lateral surface easily deform by external forces or the like. In more details, after the step of secondary molding, when the lens structure  100  is removed from the common mold, the part of the flange part  12  by warping the lens structure  100 , portions of the flange part  12  located closer to the optically functional part  11  than the first recess  13  to the optically functional part  11  are difficult to deform because being located adjacent to the optically functional part  11 , but the portions of the flange part  12  described above have room for deformation (i.e., space), which makes them more easily deformed. Therefore, forming the one or more second recesses  14  or one or more protrusions  15  in or on the first lateral surface  13   s   1  of the one or more first recesses  13  respectively, that is, forming the one or more second recesses  14  or one or more protrusions at portions of the flange part  12  that are more easily deformed, the lens structure  100  obtained after the step of secondary molding can be demolded easily than the one or more second recesses  14  or one or more protrusions are arranged in or on the second lateral surface  13   s   2 . 
     Note that the one or more second recesses  14  or the one or more protrusions  15  can be located on the second lateral surface  13   s   2  of the first recess  13 . In such a case, the one or more second recesses  14  or the one or more protrusions  15  are preferably formed not to be overlapped with the optically functional part  11  in a plan view. With this arrangement, the effect on the optical action of the optically functional part  11  can be reduced or prevented. 
     When a plurality of second recesses  14  or a plurality of protrusions  15  are formed in or on a single first recess  13 , some of the second recesses  14  or some of the protrusions  15  can be formed in or on the first lateral surface  13   s   1  of the first recess  13 , while some of the second recesses  14  or some of the protrusions  15  may be formed in or on the second lateral surface  13   s   2  of the first recess  13 . 
     The light source devices and the lens structures of the present disclosure can be used suitably to the light source devices in various applications, for example, lighting, camera flash lights, vehicular headlights, etc. In particular, the light source devices and the lens structures of the present disclosure can be used suitably for flash lights of small cameras mounted on mobile phones and other devices. 
     It is to be understood that although the present invention has been described with regard to preferred embodiments thereof, various other embodiments and variants may occur to those skilled in the art, which are within the scope and spirit of the invention, and such other embodiments and variants are intended to be covered by the following claims.