Optical receptacle and optical module

Abstract

To provide an optical receptacle capable of suppressing molding defect when an optical receptacle having a reflection surface is injection-molded.SOLUTION: An optical receptacle is disposed between photoelectric conversion elements placed on a base plate and optical transmission bodies, and is used for optically coupling the photoelectric conversion elements and end faces of the optical transmission bodies, the optical receptacle including: a bottom face coming into contact with the base plate when the optical receptacle is placed on the base plate; first optical surfaces; second optical surfaces; reflection surfaces; penetration holes which penetrate the optical receptacle in a direction perpendicular to the bottom face, and parts of inner surfaces of which are the reflection surfaces; and a rib that serves as a bridge in a direction along optical paths between the second optical surfaces and the reflection surfaces in the penetration holes.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to an optical receptacle and an optical module. [Background technology]

[0002] Conventionally, optical modules for optically connecting an optical fiber and a photoelectric conversion element arranged on a substrate are known. For example, Patent Document 1 discloses an optical component module for connecting an optical fiber and an electronic component. Patent Document 1 states that there is a demand for making such optical component modules thinner. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2004-87150 A Summary of the Invention [Problem to be solved by the invention]

[0004] 1A is a cross-sectional view showing an example of an optical module 20 for optically connecting an optical transmission body (optical fiber) such as the above and a photoelectric conversion element 10, which is a type of electronic component arranged on a substrate 10a. The optical module 20 may be used as an optical module 20 for transmission or as an optical module 20 for reception.

[0005] 1, when the optical module 20 is used as an optical module 20 for optical transmission, light emitted from the photoelectric conversion element 10 arranged on the substrate 10a enters the optical receptacle 30 at the first optical surface 31, is reflected by the reflecting surface 32, exits the optical receptacle 30 at the second optical surface 33, and reaches an optical transmission body (not shown). In this manner, in the optical module 20, the travel of the light is controlled by the optical receptacle 30, and the photoelectric conversion element 10 and the optical transmission body are optically connected.

[0006] 1A, when the surface of optical receptacle 30 that contacts substrate 10a is bottom surface 30a, first optical surface 31 is disposed on the inner surface of a recess that is recessed relative to bottom surface 30a, and reflective surface 32 is the inclined inner surface of a recess that is recessed from the top surface opposite the bottom surface. In this manner, the configuration for controlling light of optical receptacle 30 (first optical surface 31 and reflective surface 32) can be formed by forming a recess in optical receptacle 30.

[0007] When optical receptacle 30 is provided with a plurality of recesses in this manner, thin-walled portion 34 may be formed in optical receptacle 30 between two recesses (see FIG. 1B, a partially enlarged view of FIG. 1A). When optical receptacle 30 is manufactured by injection molding, the portion of the mold corresponding to thin-walled portion 34 is difficult to fill with material. Therefore, optical receptacle 30 having thin-walled portion 34 tends to have many molding defects. Note that, when optical receptacle 30 is thinned as described in the above-mentioned Patent Document 1, thin-walled portion 34 becomes thinner accordingly, and molding defects tend to become more pronounced.

[0008] An object of the present invention is to provide an optical receptacle having a reflective surface that can suppress molding defects when injection molding the optical receptacle, and to provide an optical module having the optical receptacle. [Means for solving the problem]

[0009] [1] An optical receptacle for optically coupling a photoelectric conversion element and an end face of an optical transmission body when the optical receptacle is disposed between the photoelectric conversion element and the end face of the optical transmission body, the optical receptacle comprising: a bottom surface of the optical receptacle; a first optical surface that receives light emitted from the photoelectric conversion element or emits light that has passed through the inside of the optical receptacle toward the photoelectric conversion element; a second optical surface that emits light that has been incident on the first optical surface toward the end face of the optical transmission body or receives light that has been emitted from the end face of the optical transmission body; and a coupling between the first optical surface and the second optical surface. an optical receptacle having a reflective surface that is disposed on an optical path between the first optical surface and the reflective surface and that reflects light from the first optical surface toward the second optical surface or reflects light from the second optical surface toward the first optical surface; a through hole that penetrates the optical receptacle in a direction perpendicular to the bottom surface and a part of its inner surface is the reflective surface; a rib that bridges the through hole in a direction along the optical path between the second optical surface and the reflective surface; and a gate mark or gate remainder that is disposed on an extension of the rib in a plan view, wherein the rib is connected to the reflective surface at a position other than the optical path of the light. [2] The optical receptacle described in [1], wherein the reflective surface is part of a surface of a protrusion that protrudes from the second optical surface side toward the gate remnant or gate mark side inside the through hole, and a thickness of the rib in a direction perpendicular to the bottom surface is equal to or greater than a thickness of the protrusion. [3] The optical receptacle according to [1] or [2], having a weld line that does not overlap with the optical path. [4] The optical receptacle according to [1] or [2], further comprising a weld line, wherein the width and thickness of the rib are each designed so that the weld line is out of the optical path. [5] The optical receptacle according to any one of [1] to [4], wherein in a direction perpendicular to the bottom surface, a distance between the bottom surface and an intersection of the optical axis of the second optical surface and the second optical surface is 1.1 mm or less. [6] The optical receptacle according to any one of [1] to [5], which is symmetrical with respect to a plane that is perpendicular to the bottom surface and along the optical path between the second optical surface and the reflecting surface. [7] An optical module comprising a photoelectric conversion element and the optical receptacle according to any one of [1] to [6]. Effect of the Invention

[0010] According to the present invention, it is possible to provide an optical receptacle that can suppress molding defects when injection molding an optical receptacle having a reflective surface. Also, according to the present invention, it is possible to provide an optical module that includes the optical receptacle. [Brief description of the drawings]

[0011] [Figure 1] 1A and 1B are diagrams for explaining an optical module. [Diagram 2] 2A and 2B are diagrams showing a configuration of an optical module according to an embodiment. [Diagram 3] 3A to 3C are diagrams showing the configuration of an optical receptacle according to an embodiment. [Figure 4] 4A to 4C are diagrams showing the configuration of an optical receptacle according to an embodiment. [Diagram 5] 5A and 5B are diagrams illustrating the flow of material when molding an optical receptacle according to an embodiment. [Figure 6] 6A and 6B are diagrams showing positions where weld lines occur in an optical receptacle. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] [Optical module configuration] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an optical module according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

[0013] 2A and 2B are diagrams showing a configuration of an optical module 200 according to an embodiment of the present invention, Fig. 2A is a plan view of the optical module 200, and Fig. 2B is a cross-sectional view taken along the line BB shown in Fig. 2A.

[0014] As shown in FIG. 2B, optical module 200 includes photoelectric conversion element 100 disposed on substrate 100a, and optical receptacle 300.

[0015] The optical module 200 may be used as a transmitting optical module, or may be used as a receiving optical module.

[0016] When optical module 200 is used as optical module 200 for transmission, light emitted from photoelectric conversion element 100 enters optical receptacle 300 at first optical surface 310, is reflected by reflective surface 320, and is emitted from optical receptacle 300 at second optical surface 330 to reach an end face of an optical transmission body (not shown) (see FIG. 2B).

[0017] On the other hand, when optical module 200 is used as optical module 200 for receiving, light emitted from the end face of the optical transmission body enters optical receptacle 300 at second optical surface 330, is reflected by reflective surface 320, and is emitted from optical receptacle 300 at first optical surface 310 to reach photoelectric conversion element 100.

[0018] Substrate 100a supports photoelectric conversion element 100 and optical receptacle 300. Substrate 100a is, for example, a glass composite substrate, a glass epoxy substrate, or a flexible substrate.

[0019] Photoelectric conversion element 100 is a light emitting element or a light receiving element. Photoelectric conversion element 100 is, for example, a vertical cavity surface emitting laser (VCSEL). The number of photoelectric conversion elements 100 is not particularly limited and may be one or more depending on the configuration of optical receptacle 300. In the present embodiment, the number of photoelectric conversion elements 100 is more than one.

[0020] Optical receptacle 300 is disposed so that first optical surface 310 faces photoelectric conversion element 100 on substrate 100a. Optical receptacle 300 has a configuration that can suppress molding defects during injection molding, while having reflective surface 320. The configuration of optical receptacle 300 will be described in detail separately.

[0021] The type of optical transmission body is not particularly limited. Examples of the type of optical transmission body include optical fiber and optical waveguide. The number of optical transmission bodies is not particularly limited and is selected according to second optical surface 330 of optical receptacle 300, and may be one or more. In the present embodiment, the number of optical transmission bodies is more than one.

[0022] (Optical receptacle configuration) Fig. 3A is a plan view, Fig. 3B is a front view, and Fig. 3C is a rear view of optical receptacle 300. Fig. 4A is a side view of optical receptacle 300, Fig. 4B is a cross-sectional view along line BB in Fig. 3A, and Fig. 4C is a cross-sectional view along line CC in Fig. 3A.

[0023] Optical receptacle 300 has first optical surface 310, a reflective surface 320, and a second optical surface 330. Optical receptacle 300 also has a bottom surface 300a, a through hole 304, a rib 340, and a gate remainder 350.

[0024] By having through hole 304 instead of a thin-walled portion in optical receptacle 300, the material for molding optical receptacle 300 does not flow through the portion of the molding die that corresponds to the thin-walled portion, and molding defects are suppressed. This will be described below.

[0025] FIG. 5A shows a schematic image of the inflow of material when optical receptacle 300 is viewed in plan, and FIG. 5B shows a schematic image of the inflow of material when optical receptacle 300 is viewed in cross section through through hole 304.

[0026] 5A and 5B, in plan view, the material flows around the portion of the mold corresponding to through hole 304 of optical receptacle 300. That is, in the mold, the material flows from the portion corresponding to gate 351 through both the left and right ends of optical receptacle 300 around through hole 304 and the portion corresponding to rib 340, and then flows to the portion on the front side of optical receptacle 300 (the portion corresponding to the inner surface of through hole 304 on the second optical surface 330 side), and first optical surface 310, reflecting surface 320, second optical surface 330, and the like are molded. As a result, optically functional surfaces such as first optical surface 310, reflecting surface 320, and second optical surface 330 are not molded by the material that has passed through the portion corresponding to thin-walled portion 34 of the mold, and molding defects are suppressed (see comparison of FIGS. 5A and B with FIGS. 1A and B).

[0027] Optical receptacle 300 is symmetrical with respect to a plane perpendicular to bottom surface 300a and along (parallel to) the optical path between second optical surface 330 and reflecting surface 320. Here, "symmetrical" does not only mean complete symmetry with respect to the symmetrical plane, but also includes symmetry within a range in which the manner in which material flows can be regarded as substantially similar from the standpoint of suppressing molding defects.

[0028] The components of the optical receptacle will be described in detail below.

[0029] <First optical surface> First optical surface 310 receives light emitted from photoelectric conversion element 100 or emits light that has been emitted from an end face of the optical transmission body and passed through the inside of optical receptacle 300 toward photoelectric conversion element 100.

[0030] The first optical surface 310 is not particularly limited as long as it can exhibit the above-mentioned functions. The first optical surface may be a flat surface or a curved surface. In the present embodiment, the first optical surface is a curved surface, and more specifically, is a convex lens that is convex toward the photoelectric conversion element 100.

[0031] First optical surface 310 is disposed on the bottom surface side of optical receptacle 300. More specifically, in the present embodiment, first optical surface 310 is disposed on the inner surface of a recess formed on the bottom surface 300a side that contacts substrate 100a of optical receptacle 300. From another perspective, first optical surface 310 is disposed on the opposite side of reflective surface 320 to through-hole 304 in protruding portion 302 that protrudes from second optical surface 330 side to gate remainder 350 (or gate mark) side, as shown in FIG.

[0032] The number of first optical surfaces 310 is not particularly limited, and may be one or more depending on the number of photoelectric conversion elements 100. In the present embodiment, the number of first optical surfaces 310 is eight.

[0033] <Second optical surface> Second optical surface 330 outputs light that is incident on first optical surface 310 and reflected by reflecting surface 320 toward the end face of the optical transmission body, or receives light that is emitted from the end face of the optical transmission body.

[0034] The second optical surface 330 is not particularly limited as long as it can exhibit the above-mentioned functions. The second optical surface 330 may be a flat surface or a curved surface. In the present embodiment, the second optical surface 330 is a curved surface, and more specifically, is a convex lens that is convex toward the optical transmission body.

[0035] Second optical surface 330 is disposed on the front side of optical receptacle 300. More specifically, in the present embodiment, second optical surface 330 is disposed on the inner surface of recess 303 disposed on the front side of optical receptacle 300. When optical receptacle 300 is thinned, second optical surface 330 approaches bottom surface 300a, and the distance between second optical surface 330 and bottom surface 300a becomes small. The distance between intersection O of optical axis OA of second optical surface 330 and second optical surface 330 and bottom surface 300a is, for example, 1.1 mm or less in a direction perpendicular to bottom surface 300a (a direction parallel to the optical path between the photoelectric conversion element and the first optical surface or a direction perpendicular to the substrate) (see 4B).

[0036] The number of second optical surfaces 330 is not particularly limited, and may be one or more depending on the number of optical transmission bodies. In the present embodiment, the number of second optical surfaces 330 is eight.

[0037] <Reflective surface> The reflective surface 320 is disposed on the optical path between the first optical surface 310 and the second optical surface 330, and reflects light from the first optical surface 310 toward the second optical surface 330, or reflects light from the second optical surface 330 toward the first optical surface 310.

[0038] The reflecting surface 320 is not particularly limited as long as it is a part of the inner surface of the through hole 304 and can perform the above-mentioned function. In this embodiment, the reflecting surface 320 is flat and inclined at an angle of 45° with respect to the bottom surface 300a. In this embodiment, the reflecting surface 320 is also a part of the surface of the protruding portion 302 protruding from the second optical surface 330 side to the gate remainder 350 (or gate mark) side inside the through hole 304 as shown in FIG. 4B. In this embodiment, the reflecting surface 320 is disposed on the opposite side of the protruding portion 302 from the first optical surface 310.

[0039] Through hole Through hole 304 penetrates optical receptacle 300 in a direction perpendicular to bottom surface 300a, and a part of the inner surface of through hole 304 functions as reflective surface 320. More specifically, reflective surface 320 is located on the inner surface of through hole 304 on the second optical surface 330 side. Through hole 304 is formed in place of the thin-walled portion at a position corresponding to the thin-walled portion described above. That is, through hole 304 is formed adjacent to reflective surface 320 on the rear side of reflective surface 320 so as to connect a recess on the bottom surface side of optical receptacle 300 in which first optical surface 310 is arranged and a recess on the top surface side of optical receptacle 300 in which reflective surface 320 is arranged.

[0040] By providing through hole 304 in optical receptacle 300, reflecting surface 320 and the like are not formed by the material flowing through the portion of the mold that forms the thin wall portion, but are formed by the material flowing around the portion of the mold that forms through hole 304 (see FIGS. 5A and 5B). This suppresses molding defects in optical receptacle 300. It is preferable that through hole 304 is disposed at a position where molding defects can be suppressed. In this embodiment, through hole 304 is disposed between gate remnant 350 or gate mark and second optical surface 330 when optical receptacle 300 is viewed in plan. Note that gate remnant 350 or gate mark is what is left in optical receptacle 300 after cutting gate 351, which is formed corresponding to the inlet passage of the material.

[0041] <rib> Rib 340 bridges the optical path between second optical surface 330 and reflecting surface 320 in through hole 304. As shown in FIG. 5A, rib 340 allows a passage of material from the rear side to the front side in the mold. The material that flows through the portion of the mold corresponding to rib 340 forms reflecting surface 320 and the like. As shown in FIG. 5B, the thickness of rib 340 is preferably equal to or greater than the thickness of protruding portion 302 on which reflecting surface 320 is formed, in a direction perpendicular to bottom surface 300a, from the viewpoint of improving the flow of material. Similarly, as shown in FIG. 5A, from the viewpoint of improving the flow of material, the width of the rear end of rib 340 is preferably wider than the width of the front end when optical receptacle 300 is viewed in plan. 5A, in the present embodiment, when optical receptacle 300 is viewed in plan, rib 340 has a portion on the rear side whose width gradually narrows from the rear side to the front side, and a portion on the front side whose width is constant from the rear side to the front side. That is, rib 340 has a funnel-like shape in plan view.

[0042] In the present embodiment, rib 340 is located at the center of the longitudinal direction of through-hole 304, which is the direction perpendicular to the direction in which the gate extends (left-right direction) when optical receptacle 300 is viewed in a plan view.

[0043] 6A and 6B respectively show the positions where weld lines L occur in optical receptacle 300 when such ribs 340 are not present and when they are present.

[0044] 6A and 6B, without rib 340, weld line L would be located at the center of optical receptacle 300 when viewed in plan, but with rib 340, it is not located at the center. An optically functional surface is often located at the center of optical receptacle 300 when viewed in plan. Therefore, if the weld line is located at the center as shown in FIG. 6A, it may interfere with optical coupling between photoelectric conversion element 100 and the end face of the optical transmission body. In other words, it is preferable that optical receptacle 300 has weld line L that does not overlap with the optical path. In contrast, an off-center weld line, as shown in FIG. 6B, is less disruptive.

[0045] As shown in FIG. 6B, optical receptacle 300 has guide pin 360 for positioning optical transmission body with respect to second optical surface 330, but it is preferable that weld line L and guide pin 360 do not overlap. Guide pin 360 is a convex portion that fits into a concave portion provided in a ferrule that holds the ends of multiple optical transmission bodies (optical fibers), and the optical transmission body is positioned with respect to optical receptacle 300 (second optical surface 330) by the fitting. If weld line L overlaps such guide pin 360, the shape of guide pin 360 becomes insufficient, and the positioning accuracy when fitted into the concave portion provided in the ferrule may be insufficient. Also, the strength of guide pin 360 may be insufficient to fit into the concave portion. Therefore, it is preferable that guide pin 360 and weld line L do not overlap. In the present embodiment, the number of guide pins 360 is two, and when optical receptacle 300 is viewed in plan, they are arranged on the front side, one on each side, spaced apart.

[0046] The detailed position, shape, size, etc. of rib 340 may be appropriately adjusted in relation to the position of an optically functional surface for controlling light in optical receptacle 300 and / or the position of guide pin 360, and the position where a weld line occurs. Specifically, for example, the width and thickness of rib 340 are preferably designed so that weld line L is off the optical path. Examples of optically functional surfaces include first optical surface 310, second optical surface 330, reflecting surface 320, etc.

[0047] From the viewpoint of adjusting the position where the weld line L occurs, the rib 340 is preferably as follows.

[0048] That is, when optical receptacle 300 is viewed in plan, and the length in a direction perpendicular to the direction in which rib 340 extends to bridge through hole 304 (left-right direction) is taken as the width, minimum width W1 of rib 340 is preferably larger than minimum width W2 from side wall 300b of optical receptacle 300 to inner surface 304b on the side wall side of through hole 304 on both sides of optical receptacle 300 (see FIG. 5A). This allows the resin flowing from the portion corresponding to rib 340 in the molding die to flow around to the portions corresponding to first optical surface 310 and reflecting surface 320 of the molding die more quickly than the resin flowing from the portions corresponding to both sides of optical receptacle 300, and the weld lines are less likely to interfere with the control of light on the optical function surface.

[0049] Alternatively, it is preferable that the minimum width W1 is the same as the minimum width W2, which reduces overlap between the weld line L and the first optical surface 310, the second optical surface 330, and the guide pin 360.

[0050] Moreover, the thickness of rib 340 is preferably equal to or greater than half the thickness of optical receptacle 300. Here, the thickness refers to the length in a direction perpendicular to bottom surface 300a of optical receptacle 300. Moreover, the thickness of rib 340 is preferably equal to or greater than the distance from the top surface of optical receptacle 300 to first optical surface 310 in a direction perpendicular to bottom surface 300a of the optical receptacle.

[0051] Examples of the manner in which the weld line L deviates from the optical path include the following. That is, when optical receptacle 300 is viewed in plan, weld line L is present between guide pin 360 and an optical path formed by first optical surface 310, reflective surface 320, and second optical surface 330. When optical receptacle 300 is viewed in plan, weld line L is present between two optical paths formed by two adjacent sets of first optical surface 310, reflective surface 320, and second optical surface 330. When optical receptacle 300 is viewed in plan, weld line L is present between side wall 300b of optical receptacle 300 and guide pin 360.

[0052] <Gate remains, gate marks> Gate 351 corresponds to the passage of material when optical receptacle 300 is injection molded, and is left in optical receptacle 300 after molding (see FIGS. 5A and 5B). Optical receptacle 300 may have gate remainder 350 in which a part of gate 351 remains in optical receptacle 300 after gate 351 is cut, or may have a gate mark which is a cut mark left in optical receptacle 300 after gate 351 is cut so that it does not remain in optical receptacle 300. In this embodiment, gate 351 is present on the surface (back surface) opposite second optical surface 330 of optical receptacle 300. As a result, gate remainder 350 or gate mark is also present on the surface (back surface) opposite second optical surface 330. Furthermore, optical receptacle 300 has gate mark or gate remainder 350 arranged at a position on an extension line of rib 340 when viewed in a plan view.

[0053] (effect) The optical receptacle according to the embodiment of the present invention has a through hole that penetrates the optical receptacle and has a part of its inner surface that is a reflective surface, and a rib, which makes it possible to suppress molding defects when the optical receptacle is injection molded. [Industrial Applicability]

[0054] The optical receptacle and optical module according to the present invention are useful, for example, in optical communications using an optical transmission medium. [Explanation of symbols]

[0055] 10, 100 Photoelectric conversion element 10a, 100a board 20, 200 Optical Module 30, 300 Optical Receptacle 30a, 300a bottom 31, 310 1st optical surface 32, 320 reflective surface 33, 330 Second optical surface 34 Thin section 302 Protrusion 303 Recess 304 Through hole 340 Rib 350 gates remaining Gate 351 360 Guide Pin L Weld line

Claims

1. An optical receptacle for optically coupling an end face of an optical transmission body and a photoelectric conversion element disposed on a substrate, the optical receptacle comprising: A bottom surface of the optical receptacle; a first optical surface that receives light emitted from the photoelectric conversion element or that outputs light that has been emitted from an end face of the optical transmission body and passed through an interior of the optical receptacle toward the photoelectric conversion element; a second optical surface that outputs the light incident on the first optical surface toward the end surface of the optical transmission body or that receives the light output from the end surface of the optical transmission body; a reflecting surface disposed on an optical path between the first optical surface and the second optical surface, the reflecting surface reflecting light from the first optical surface toward the second optical surface or reflecting light from the second optical surface toward the first optical surface; a through hole that penetrates the optical receptacle in a direction perpendicular to the bottom surface, and a part of an inner surface of the through hole is the reflective surface; a rib that bridges the through hole in a direction along an optical path between the second optical surface and the reflecting surface; A gate mark or gate residue disposed on an extension line of the rib when viewed in a plan view; having The rib is connected to the reflecting surface at a position other than the optical path of the light. Optical receptacle.

2. the reflecting surface is a part of a surface of a protruding portion inside the through hole, the protruding portion protruding from the second optical surface side to the gate remainder or gate mark side, The optical receptacle according to claim 1 , wherein a thickness of the rib is equal to or greater than a thickness of the protrusion in a direction perpendicular to the bottom surface.

3. The optical receptacle of claim 1 having a weld line that does not overlap the optical path.

4. Further having a weld line, The width of the rib and the thickness of the rib are each designed so that the weld line is out of the optical path. The optical receptacle of claim 1 .

5. 2 . The optical receptacle according to claim 1 , wherein a distance between an intersection of an optical axis of the second optical surface and the second optical surface and the bottom surface in a direction perpendicular to the bottom surface is 1.1 mm or less.

6. The optical receptacle of claim 1 , wherein the optical receptacle is symmetrical about a plane perpendicular to the bottom surface and along an optical path between the second optical surface and the reflective surface.

7. A photoelectric conversion element; An optical receptacle according to any one of claims 1 to 6; An optical module comprising:

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