Optical module and optical connector cable

Abstract

To provide an optical module capable of avoiding adhesion of dust to a mirror part.SOLUTION: The optical module includes an optical element, a lens component having therein an optical path between an optical fiber and the optical element, and a protective member. The lens component includes an optical-fiber-holding portion that holds the optical fiber, a lens portion that is formed on an optical path between the optical fiber and the optical element, and a mirror portion that forms a part of a surface of the lens component and bends the optical path between the optical fiber and the optical element. The protection member is attached to a surface of the lens component and configured to prevent the mirror part from being exposed.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to an optical module and an optical connector cable. [Background technology]

[0002] Patent Document 1 discloses an optical component and an optical connector cable. This optical component includes a substrate on which an optical element is mounted, and a lens component disposed on the mounting surface of the substrate. The lens component has a first surface located on the outside and a second surface located on the inside opposite the first surface and facing the mounting surface. A recess is formed in the first surface, and part of the inner surface of the recess serves as a light-reflecting surface.

[0003] Patent Document 2 discloses an optical module and an optical connector cable. This optical module includes an optical coupling module that optically couples an optical element mounted on a substrate with an optical fiber. The optical coupling module has a mirror that changes the propagation direction of light emitted from the optical fiber, and a lens that converges the light reflected by the mirror and makes it incident on the optical element. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2019-082508 [Patent Document 2] International Publication No. 2023 / 013348 Summary of the Invention [Problem to be solved by the invention]

[0005] For example, a lens component disclosed in Patent Document 1 is used to couple an optical fiber with an optical element arranged on a substrate. This lens component has a recess formed on the surface opposite the substrate. A part of the inner surface of the recess functions as a mirror (light-reflecting surface) that reflects light propagating inside the lens component. In such a configuration, if dust enters the recess and adheres to the mirror, the optical reflectivity of the mirror decreases, resulting in a decrease in the optical coupling efficiency between the optical element and the optical fiber. In particular, if the lens component is not covered by a housing or the like, surrounding dust is likely to adhere to the mirror.

[0006] The present disclosure aims to provide an optical module and an optical connector cable that can prevent dust from adhering to a mirror portion. [Means for solving the problem]

[0007] An optical module according to an embodiment of the present disclosure includes an optical element, a lens component having an optical path between an optical fiber and the optical element therein, and a protective member. The lens component has an optical fiber holding portion that holds the optical fiber, a lens portion formed on the optical path between the optical fiber and the optical element, and a mirror portion that forms part of the surface of the lens component and bends the optical path between the optical fiber and the optical element. The protective member is attached to the surface of the lens component and is configured to prevent the mirror portion from being exposed. [Effects of the Invention]

[0008] According to the present disclosure, an optical module and an optical connector cable that can prevent dust from adhering to a mirror portion can be provided. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a perspective view illustrating an optical connector cable according to an embodiment of the present disclosure. [Figure 2] FIG. 2 is a perspective view of the optical connector cable showing a state before the optical fiber cable is attached to the optical module. [Figure 3]FIG. 3 is a cross-sectional view of the optical module. [Figure 4] FIG. 4 is a cross-sectional view showing the configuration of an optical module according to a first modified example. [Figure 5] FIG. 5 is a cross-sectional view showing the configuration of an optical module according to a second modification. [Figure 6] FIG. 6 is a cross-sectional view showing the configuration of an optical module according to a third modification. DETAILED DESCRIPTION OF THE INVENTION

[0010] [Description of the embodiments of the present disclosure] First, the contents of the embodiments of the present disclosure will be listed and described. [1] An optical module according to one embodiment of the present disclosure includes an optical element, a lens component having an optical path between an optical fiber and the optical element therein, and a protective member. The lens component has an optical fiber holding portion that holds the optical fiber, a lens portion formed on the optical path between the optical fiber and the optical element, and a mirror portion that forms part of the surface of the lens component and bends the optical path between the optical fiber and the optical element. The protective member is attached to the surface of the lens component and is configured to prevent the mirror portion from being exposed.

[0011] In the optical module [1] above, a protective member is attached to the surface of the lens component to prevent the mirror from being exposed. This prevents dust from adhering to the mirror. This prevents a decrease in the optical reflectance of the mirror and a decrease in the optical coupling efficiency between the optical element and the optical fiber.

[0012] [2] In the optical module of [1] above, the surface may have a recess, the lens portion may form part of the inner surface of the recess, and the protective member may close the opening of the recess. In this case, the lens portion is housed and protected in a space surrounded by the recess and the protective member. This prevents dust from entering the recess and preventing dust from adhering to the mirror portion.

[0013] [3] In the optical module of [2] above, the protective member may be an adhesive film attached to the surface, which allows the opening of the recess to be closed with a simple structure.

[0014] [4] In the optical module of [2] above, the protective member may be a resin adhered to the surface. In this case, too, the opening of the recess can be closed with a simple structure.

[0015] [5] In the optical module of [1] above, the protective member may be in contact with the surface of the mirror around the periphery, with a gap between the protective member and the mirror. In this case, it is possible to prevent dust from adhering to the mirror and to prevent a decrease in the light reflectance of the mirror due to the installation of the protective member.

[0016] [6] In the optical module of [1] above, the protective member may include a fibrous or porous material that covers the mirror portion. In this case, the protective member can have a simple structure.

[0017] [7] An optical connector cable according to an embodiment of the present disclosure includes an optical module according to any one of [1] to [6] above, and an optical fiber cable having an optical fiber, the tip of which is held by the optical module. This optical connector cable can prevent dust from adhering to the mirror portion. This prevents a decrease in the optical reflectivity of the mirror portion and a decrease in the optical coupling efficiency between the optical element and the optical fiber.

[0018] [Details of the embodiments of the present disclosure] Specific examples of the present disclosure will be described below with reference to the drawings. Note that the present invention is not limited to these examples, but is defined by the claims, and is intended to include all modifications within the meaning and scope equivalent to the claims. In the following description, the same elements in the description of the drawings will be given the same reference numerals, and duplicate explanations will be omitted.

[0019] Fig. 1 is a perspective view showing an optical connector cable 2 according to an embodiment of the present disclosure. Fig. 2 is a perspective view showing the optical connector cable 2 in a state before an optical fiber cable 30 is attached to an optical module 1. As shown in Figs. 1 and 2, the optical connector cable 2 includes an optical module 1 and an optical fiber cable 30. The optical module 1 includes a circuit board 10 and a lens component 20. The lens component 20 is disposed on a flat main surface 10a (mounting surface) of the circuit board 10 and fixed to the main surface 10a.

[0020] Fig. 3 is a cross-sectional view of the optical module 1. As shown in Fig. 3, the optical module 1 further includes an optical element 41. The optical element 41 is mounted on the main surface 10a of the circuit board 10 and is located between the circuit board 10 and the lens component 20. The lens component 20 is disposed so as to cover the optical element 41. The optical element 41 is, for example, a photoelectric conversion element such as a light receiving element such as a photodiode (PD) or a light emitting element such as a vertical cavity surface emitting laser (VCSEL), and has an optical axis along a direction intersecting the main surface 10a (for example, a normal direction to the main surface 10a).

[0021] 1 and 2 again, the optical fiber cable 30 has a plurality of optical fibers 31 and a holding member 32. Most of each optical fiber 31 is housed inside a coating, and a tip portion of each optical fiber 31 is exposed to the outside from the coating. Each optical fiber 31 is optically coupled to an optical element 41 by a lens component 20. The holding member 32 determines the fiber pitch and extension direction between the tip portions of the plurality of optical fibers 31. The holding member 32 aligns the tip portions of the plurality of optical fibers 31 so that they are, for example, parallel to each other.

[0022] As shown in Fig. 3, lens component 20 has an optical path L1 therein between optical fiber 31 and optical element 41. To allow light to propagate therethrough, at least the region of lens component 20 that includes optical path L1 is made of a transparent material through which light can propagate, such as glass or transparent resin. The transparent resin is, for example, a polyetherimide resin. In one example, lens component 20 is a plate-like member having a rectangular planar shape, and the entire lens component 20 is made of a light-transmitting material.

[0023] The lens component 20 has a plurality of grooves 21, a mirror portion 22, and a lens portion 29. The plurality of grooves 21 are formed in an area of ​​the surface 20a of the lens component 20 closer to the optical fiber cable 30. The tip portion of each aligned optical fiber 31 is placed in each of the plurality of grooves 21 and fixed to each of the plurality of grooves 21 by an adhesive (not shown). The plurality of grooves 21 are optical fiber holding portions that hold the plurality of optical fibers 31.

[0024] The mirror section 22 is optically coupled to a plurality of optical fibers 31. As shown in Fig. 3, the mirror section 22 bends the optical path L1 between the optical fibers 31 and the optical element 41 by changing the propagation direction of the light. The mirror section 22 changes the propagation direction of the light propagating from the optical fibers 31 in the horizontal direction (the direction along the main surface 10a of the circuit board 10) to the vertical direction (the direction intersecting with the main surface 10a). Alternatively, the mirror section 22 changes the propagation direction of the light propagating in the vertical direction from the optical element 41 to the horizontal direction.

[0025] The mirror portion 22 forms part of the surface 20a of the lens component 20. In this embodiment, the lens component 20 has a recess 20b formed in the surface 20a, and the mirror portion 22 forms part of the inner surface of the recess 20b. The recess 20b is recessed on the surface 20a toward the circuit board 10. Of the multiple inner surfaces that make up the recess 20b, the inner surface that is closer to the optical fiber 31 is inclined with respect to the optical path L1. The mirror portion 22 is formed by this inclined inner surface. The inner surface that makes up the mirror portion 22 reflects light due to the difference in refractive index between the material that makes up the lens component 20 and the air present in the recess 20b.

[0026] The lens portion 29 is formed on the optical path between the optical fiber 31 and the optical element 41. In one example, as shown in FIG. 3, the lens portion 29 is formed in a convex shape on the surface of the lens component 20 that faces the circuit board 10. In this case, the lens portion 29 is located on the optical path L1 between the optical element 41 and the mirror portion 22. The mirror portion 22 is optically coupled to the optical element 41 via the lens portion 29.

[0027] The protective member 23 is attached to the surface 20a of the lens component 20 and is configured to prevent the mirror portion 22 from being exposed without coming into contact with the mirror portion 22. The protective member 23 of this embodiment is an adhesive film attached to the surface 20a, and seals the opening of the recess 20b by adhering to the periphery of the opening. The adhesive film is made of a resin film with an adhesive applied to one side thereof. The recess 20b and the protective member 23 form a space that holds air in contact with the mirror portion 22. The opening of the recess 20b may be airtightly sealed by the protective member 23. The film may be made of a material such as polyimide, cellophane, polyester, polypropylene, or polyolefin.

[0028] The effects obtained by the optical module 1 and optical connector cable 2 according to the present embodiment described above will now be described. In a conventional optical module not provided with a protective member 23, if dust enters and adheres to the mirror portion 22, the optical reflectivity of the mirror portion 22 decreases, resulting in a decrease in the optical coupling efficiency between the optical element 4 and the optical fiber 31. In particular, if the optical module is not covered by a housing or the like, surrounding dust is likely to adhere to the mirror portion 22. In general-purpose electronic devices such as personal computers, the provision of a housing or the like that covers the optical module is sometimes omitted in order to reduce size and weight. Furthermore, such electronic devices are sometimes provided with ventilation holes to release heat generated inside. In such cases, for example, dust entering through the ventilation holes is likely to cause the above-mentioned problems.

[0029] In this embodiment, protective member 23 is attached to surface 20a of lens component 20 to prevent mirror portion 22 from being exposed. This prevents dust from adhering to mirror portion 22. This prevents a decrease in the optical reflectance of mirror portion 22 and a decrease in the optical coupling efficiency between optical element 41 and optical fiber 31.

[0030] As in this embodiment, the surface 20a may have a recess 20b, the mirror portion 22 may form part of the inner surface of the recess 20b, and the protective member 23 may close the opening of the recess 20b. In this case, the lens portion 29 is housed and protected in the space surrounded by the recess 20b and the protective member 23. This prevents dust from entering the recess 20b and preventing dust from adhering to the mirror portion 22.

[0031] As in this embodiment, the protective member 23 may be an adhesive film attached to the surface 20a, which allows the opening of the recess 20b to be closed with a simple structure.

[0032] [First Modification] 4 is a cross-sectional view showing the configuration of an optical module 1A according to a first modification of the present disclosure. The optical connector cable 2 may include the optical module 1A of this modification instead of the optical module 1 of the above embodiment. As shown in FIG. 4, the optical module 1A of this modification includes a protective member 26 instead of the protective member 23 of the above embodiment.

[0033] The protective member 26 is attached to the surface 20a of the lens component 20 and is configured to prevent the mirror portion 22 from being exposed without coming into contact with the mirror portion 22. The protective member 26 of this modified example is a resin adhered to the surface 20a, and adheres to the periphery of the opening of the recess 20b, thereby blocking the opening of the recess 20b. As a result, the recess 20b and the protective member 26 form a space that retains air in contact with the mirror portion 22. The opening of the recess 20b may be airtightly sealed by the protective member 26. Examples of resins used for the protective member 26 include acrylic and epoxy resins. The resin preferably has high viscosity before hardening to prevent contact with the mirror portion 22. In one example, the material of the protective member 26 is resin putty.

[0034] As in this modification, the protective member 26 may be made of resin and fixed to the surface 20a. In this case, the same effects as in the above embodiment can be obtained, and the opening of the recess 20b can be closed with a simple structure.

[0035] [Second Modification] 5 is a cross-sectional view showing the configuration of an optical module 1B according to a second modification of the present disclosure. The optical connector cable 2 may include the optical module 1B of this modification instead of the optical module 1 of the above embodiment. As shown in FIG. 5, the optical module 1B of this modification includes a protective member 26 and a protective member 27 instead of the protective member 23 of the above embodiment.

[0036] The protective member 27 contacts the surface 20a around the mirror portion 22, but does not contact the mirror portion 22 due to a gap between the protective member 27 and the mirror portion 22. In the illustrated example, the protective member 27 is housed in the recess 20b and contacts the inner surface of the recess 20b around the mirror portion 22. The protective member 27 may be held in the recess 20b by the protective member 26 of the first modified example (or the protective member 23 of the above embodiment), or may be fixed to the lens component 20 by being adhered to the surface 20a (for example, to the inner surface of the recess 20b). In the illustrated example, the protective member 27 has an L-shape in a cross section including the optical path L1, but the shape of the protective member 27 is not limited to this. The material of the protective member 27 is, for example, resin. The material of the protective member 27 may be the same as or different from the material of the lens component 20. If the material of the protective member 27 is the same as the material of the lens component 20, adhesion between the protective member 27 and the lens component 20 is facilitated.

[0037] As in this modification, protective member 27 may be in contact with surface 20a around mirror portion 22, with a gap between it and mirror portion 22. In this case, it is possible to prevent dust from adhering to mirror portion 22 and to avoid a decrease in the light reflectance of mirror portion 22 due to the installation of protective member 27. Furthermore, by providing protective member 27 in addition to protective member 26 (or protective member 23), it is possible to more effectively prevent dust from adhering to mirror portion 22.

[0038] [Third Modification] 6 is a cross-sectional view showing the configuration of an optical module 1C according to a third modification of the present disclosure. The optical connector cable 2 may include the optical module 1C of this modification instead of the optical module 1 of the above embodiment. As shown in FIG. 6, the optical module 1C of this modification includes a protective member 26 and a protective member 28 instead of the protective member 23 of the above embodiment.

[0039] The protective member 28 includes a fibrous or porous material that covers the mirror portion 22. The fibrous material is, for example, cotton. The porous material is, for example, foamed resin. Unlike the above-described embodiment and modifications, the protective member 28 of this modification may contact the mirror portion 22. The protective member 28 is arranged to cover the mirror portion 22. In the illustrated example, the protective member 28 is housed in the recess 20b. The protective member 28 may be held in the recess 20b by the protective member 26 of the first modification (or the protective member 23 of the above-described embodiment), or may be fixed to the lens component 20 by being adhered to the surface 20a (for example, to the inner surface of the recess 20b). When the protective member 28 is adhered to the surface 20a, the adhesive used is applied so as not to come into contact with the mirror portion 22.

[0040] As in this modification, the protective member 28 may include a fibrous body or a porous body that covers the mirror portion 22. The fibrous body and the porous body have only a small effect on the light reflectance even when they come into contact with the mirror portion 22. This modification not only achieves the same effects as the above embodiment, but also allows the protective member 28 to have a simple structure. Additionally, in many cases, the fibrous body and the porous body are lightweight, which contributes to reducing the weight of the optical module 1C. Additionally, in many cases, the fibrous body and the porous body are flexible, which reduces the risk of damaging the mirror portion 22 during the assembly of the optical module 1C.

[0041] The optical module and optical connector cable according to the present disclosure are not limited to the above-described embodiment, and various other modifications are possible. For example, in the above-described embodiment and each modification, the lens component 20 has a recess 20b, and the mirror portion 22 is formed as the inner surface of the recess 20b. However, this is not limiting, and the mirror portion 22 may be a part of the surface 20a of the lens component 20 that is not a recess. Even in this case, the same effect as the above-described embodiment can be obtained by attaching a protective member to the surface 20a of the lens component 20 and configuring the protective member to prevent the mirror portion 22 from being exposed. [Explanation of symbols]

[0042] 1, 1A, 1B, 1C...Optical module 2...Optical connector cable 4...Optical element 10...Circuit board 10a…main surface 20...Lens parts 20a…Surface 20b...recess 21...Groove 22...Mirror section 23, 26, 27, 28...Protective members 29...Lens section 30...Fiber optic cable 31...Optical fiber 32...Retaining member 41...Optical element L1…light path

Claims

1. an optical element; a lens component having an optical path therein between the optical fiber and the optical element; A protective member; Equipped with The lens component includes: an optical fiber holding portion that holds the optical fiber; a lens portion formed on an optical path between the optical fiber and the optical element; a mirror portion that forms a part of the surface of the lens component and bends the optical path between the optical fiber and the optical element; and The protective member is attached to the surface of the lens component and is configured to prevent the mirror portion from being exposed.

2. the surface has a recess; the mirror portion forms a part of the inner surface of the recess; The optical module according to claim 1 , wherein the protective member covers an opening of the recess.

3. The optical module according to claim 2 , wherein the protective member is an adhesive film attached to the surface.

4. 3. The optical module according to claim 2, wherein the protective member is a resin adhered to the surface.

5. The optical module according to claim 1 , wherein the protection member is in contact with the surface around the periphery of the mirror portion, and has a gap between the protection member and the mirror portion.

6. The optical module according to claim 1 , wherein the protective member includes a fibrous or porous material that covers the mirror portion.

7. an optical module according to any one of claims 1 to 6; an optical fiber cable having an optical fiber, the tip of the optical fiber being held in the optical module; An optical connector cable comprising:

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