Optical coupler, photoelectric conversion circuit module, and optical transceiver

Abstract

This optical coupler (1) comprises: an optical fiber fixing part (4); a reflection part (3) that changes the traveling direction of light (L) from a first direction (DIR1) to a second direction (DIR2) orthogonal to the first direction; and a holding part (2) that holds each of the optical fiber fixing part (4) and the reflection part (3). The holding part (2) includes a first side wall part (21), a second side wall part (22), and a third side wall part (23) that, when viewed in the second direction, is positioned on the opposite side of the second side wall part (22) in a third direction (DIR3) so as to sandwich the optical fiber fixing part (4) and the reflection part (3). The optical fiber fixing part (4) and the reflection part (3) are both connected to the second side wall part (22) and the third side wall part (23). At least one among the width (D1) of the first side wall part (21) in the first direction, the width (D2) of the second side wall part (22) in the third direction, and the width (D3) of the third side wall part (23) in the third direction increases continuously in the second direction.

Description

[Technical Field]

[0001] The present invention relates to an optical coupler, an optoelectronic conversion circuit module, and an optical transceiver. [Background technology]

[0002] An example of a conventional invention related to an optical coupler is the optical module described in Patent Document 1. The optical module described in Patent Document 1 includes a package, a microlens, an optical fiber connector, a positioning means, and a fixing means. The package mounts at least one of a light-emitting element and a light-receiving element. The microlens is fixed to the package so as to be positioned on the optical path of light emitted from the light-emitting element and / or light incident on the light-receiving element. The optical fiber connector has an optical path changing section that changes the direction of the optical path so that the light-emitting element and / or the light-receiving element and the optical fiber are optically coupled via the microlens. The optical fiber connector also has a V-groove array formed therein for mounting the optical fiber. The positioning means mechanically positions the package and the optical fiber connector so that the light-emitting element and / or the light-receiving element and the optical fiber are optically coupled via the microlens and the optical path changing section. The fixing means detachably fixes the optical fiber connector to the package. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-65358 Summary of the Invention [Problem to be solved by the invention]

[0004] In the optical module described in Patent Document 1, the microlens, the optical path changing section, and the V-groove array are each separate members fixed by fixing means, which makes it difficult to maintain positioning accuracy and may result in a decrease in coupling efficiency between the light emitting element and / or light receiving element, the microlens, the optical path changing section, and the optical fiber.

[0005] Furthermore, disturbance light may enter the optical module from outside and mix with the light emitted from the optical fiber, which may result in a decrease in the S / N ratio.

[0006] Therefore, an object of the present invention is to provide an optical coupler, an optoelectric conversion circuit module, and an optical transceiver that can suppress a decrease in coupling efficiency and a decrease in S / N ratio. [Means for solving the problem]

[0007] An optical coupler according to one aspect of the present invention comprises: An optical coupler integrally formed from a material including glass and a filler mixed in the glass, an optical fiber fixing portion that fixes each of a plurality of optical fibers that emit light in a first direction; a reflector that changes the traveling direction of the light emitted from any one of the plurality of optical fibers from the first direction to a second direction perpendicular to the first direction; a holder that holds the optical fiber fixing portion and the reflector, respectively; It is equipped with The holding portion is a first sidewall portion having a shape extending in a third direction perpendicular to the first direction and the second direction; a second side wall portion connected to the first side wall portion and having a shape extending in the first direction; a third side wall portion that is connected to the first side wall portion and has a shape that extends in the first direction, and that is located on an opposite side of the second side wall portion in the third direction, with the optical fiber fixing portion and the reflecting portion sandwiched between them, as viewed in the second direction; It contains an end portion of the optical fiber fixing portion and an end portion of the reflecting portion along the third direction are connected to the second side wall portion and the third side wall portion, respectively; At least one of the width of the first side wall portion along the first direction, the width of the second side wall portion along the third direction, and the width of the third side wall portion along the third direction continuously increases toward the second direction. [Effects of the Invention]

[0008] According to the optical coupler, photoelectric conversion circuit module, and optical transceiver of the present invention, it is possible to suppress a decrease in coupling efficiency and a decrease in the S / N ratio. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a perspective view of an optical coupler 1. FIG. [Figure 2] FIG. 2 is a cross-sectional view of the optical coupler 1 and the optical fiber 5. As shown in FIG. [Figure 3] FIG. 3 is a plan view of the optical coupler 1 as viewed in the opposite direction to the second direction DIR2. [Figure 4] FIG. 4 is a cross-sectional view of the optical coupler 1 and the optical fiber 5, showing how the disturbance light AL enters the optical coupler 1. As shown in FIG. [Figure 5] FIG. 5 is a cross-sectional view of the optical coupler 1 a and the optical fiber 5 . [Figure 6] FIG. 6 is a cross-sectional view of the optical coupler 1b and the optical fiber 5. As shown in FIG. [Figure 7] FIG. 7 is a plan view of the optical coupler 1c as viewed in the opposite direction to the second direction DIR2. [Figure 8] FIG. 8 is a perspective view of the photoelectric conversion circuit module 10 and the optical fiber 5. As shown in FIG. [Figure 9] FIG. 9 is a cross-sectional view of the photoelectric conversion circuit module 10 and the optical fiber 5 taken along the line AA. [Figure 10] FIG. 10 is a perspective view of the photoelectric conversion circuit module 10a and the optical fiber 5. As shown in FIG. [Figure 11]FIG. 11 is a perspective view of the optical transceiver 100 and the optical fiber 5. As shown in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0010] [First embodiment] [Structure of optical coupler 1] An optical coupler 1 according to a first embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view of the optical coupler 1. FIG. 2 is a cross-sectional view of the optical coupler 1 and an optical fiber 5. Note that in FIGS. 1 and 2, only a representative filler P1 among a plurality of fillers P1 is designated by a reference symbol. Also, in FIG. 2, the second side wall portion 22 and the third side wall portion 23 are omitted. FIG. 3 is a plan view of the optical coupler 1 viewed in the opposite direction to the second direction DIR2.

[0011] In this specification, directions are defined as follows. As shown in FIG. 1 , the direction in which the optical fiber fixing portion 4 and the reflecting portion 3 are arranged in this order is defined as a first direction DIR1. The direction in which the reflecting portion 3 and the bottom portion 24 are arranged in this order is defined as a second direction DIR2. The direction in which the second side wall portion 22 and the third side wall portion 23 are arranged in this order is defined as a third direction DIR3. The first direction DIR1, the second direction DIR2, and the third direction DIR3 are perpendicular to each other. However, the first direction DIR1, the second direction DIR2, and the third direction DIR3 in this specification are defined for the convenience of explanation and do not necessarily coincide with the first direction DIR1, the second direction DIR2, and the third direction DIR3 when the optical coupler 1 is in use.

[0012] The optical coupler 1 is a device for changing the traveling direction of light emitted from an optical fiber and outputting it to a photoelectric conversion circuit or the like, or for changing the traveling direction of light emitted from a photoelectric conversion circuit or the like and outputting it to an optical fiber. In this embodiment, a case will be described in which the optical coupler 1 changes the traveling direction of light L emitted from an optical fiber 5 from a first direction DIR1 to a second direction DIR2. As shown in FIG. 2 , the optical coupler 1 has an incident surface S11 onto which the light L emitted from the optical fiber 5 is incident, and an exit surface S12 from which the light L is output in the second direction DIR2. The structure of the optical coupler 1 will be described in detail below.

[0013] As shown in Fig. 1, the optical coupler 1 includes a holding portion 2, a reflecting portion 3, and an optical fiber fixing portion 4. The optical coupler 1 is integrally molded from glass containing a filler. The optical coupler 1 is a single member. Here, a single member means a member that has a structure that makes it impossible to separate the members without breaking them. Therefore, for example, a member in which two resin pieces are fixed with screws is not a single member.

[0014] The optical coupler 1 is integrally molded from a material including glass M1 and a plurality of fillers P1 mixed into the glass M1. Glass is an amorphous material that exhibits a glass transition phenomenon. Examples of glass include simple oxide glasses such as SiO2, B2O3, P2O5, GeO2, and AS3O3; silicate glasses such as Li2O-SiO2, Na2O-SiO2, and K2O-SiO2; aluminosilicate glasses such as Na2O-Al2O3-SiO2 and CaO-Al2O3-SiO2; borate glasses such as Li2O-B2O3 and Na2O-B2O3; aluminoborate glasses such as CaO-Al2O3-B2O3; and borosilicate glasses such as Na2O-Al2O3-B2O3-SiO2.

[0015] The plurality of fillers P1 are metal oxide particles such as crystalline silica, amorphous silica, alumina, magnesium oxide, and titanium oxide. Each of the plurality of fillers P1 has a non-spherical shape. The plurality of fillers P1 are dispersed throughout the glass M1. Each of the plurality of fillers P1 may have a spherical shape. The plurality of fillers P1 may be dispersed uniformly throughout the glass M1, or may be dispersed unevenly throughout the glass M1.

[0016] The holding part 2 holds each of the reflecting part 3 and the optical fiber fixing part 4. The holding part 2 is connected to each of the reflecting part 3 and the optical fiber fixing part 4. The holding part 2 includes a first side wall part 21, a second side wall part 22, a third side wall part 23, and a bottom part 24. It should be noted that the holding part 2 does not necessarily have to include the bottom part 24.

[0017] The first side wall 21 is connected to each of the second side wall 22, the third side wall 23, and the bottom 24. More specifically, the first side wall 21 has a shape extending in the third direction DIR3. In this embodiment, the end face of the first side wall 21 in the first direction DIR1 and the end face in the opposite direction to the first direction DIR1 (the first side face and the second side face aligned in the first direction DIR1) are tapered as shown in FIG. 2. More specifically, when viewed in the third direction DIR3, the angle θ1 formed between the end face of the first side wall 21 in the first direction DIR1 and the first direction DIR1 is an obtuse angle. Furthermore, when viewed in the third direction DIR3, the angle θ2 formed between the end face of the first side wall 21 in the opposite direction to the first direction DIR1 and the first direction DIR1 is an acute angle. Therefore, the end face of the first side wall portion 21 in the first direction DIR1 and the end face of the first side wall portion 21 in the opposite direction to the first direction DIR1 are not parallel. The first width D1 of the first side wall portion 21 along the first direction DIR1 continuously increases toward the second direction DIR2. The end face of the first side wall portion 21 in the third direction DIR3 is connected to the third side wall portion 23, as shown in FIG. 1. The end face of the first side wall portion 21 in the opposite direction to the third direction DIR3 is connected to the second side wall portion 22. The end face of the first side wall portion 21 in the second direction DIR2 is connected to the bottom portion 24, as shown in FIG. 2. In this embodiment, the filler P1 is exposed on the surface of the first side wall portion 21. The end faces of the first side wall portion 21 in the first direction DIR1 and the end faces in the opposite direction to the first direction DIR1 (the first and second side faces aligned in the first direction DIR1) do not have to be tapered. Also, the filler P1 does not have to be exposed on the surface of the first side wall portion 21.

[0018] As shown in FIG. 1 , the second side wall 22 is connected to each of the first side wall 21, the bottom 24, the reflector 3, and the optical fiber fixing portion 4. More specifically, the second side wall 22 is located in the opposite direction of the third direction DIR3 from the third side wall 23. The second side wall 22 has a shape extending in the first direction DIR1. In this embodiment, the end face of the second side wall 22 in the third direction DIR3 and the end face in the opposite direction to the third direction DIR3 (the third side face and the fourth side face aligned in the third direction DIR3) are inclined in a tapered shape. More specifically, when viewed in the first direction DIR1, the angle θ3 formed between the end face of the second side wall 22 in the opposite direction to the third direction DIR3 and the third direction DIR3 is an acute angle. When viewed in the first direction DIR1, the angle θ4 formed between the end face of the second side wall portion 22 in the third direction DIR3 and the third direction DIR3 is an obtuse angle. The end face of the second side wall portion 22 in the opposite direction to the third direction DIR3 and the end face of the second side wall portion 22 in the third direction DIR3 are not parallel to each other. The second width D2 of the second side wall portion 22 along the third direction DIR3 continuously increases toward the second direction DIR2. A portion of the end face of the second side wall portion 22 in the third direction DIR3 is connected to each of the end face of the first side wall portion 21 in the opposite direction to the third direction DIR3, the reflector 3, and the optical fiber fixing portion 4. The end face of the second side wall portion 22 in the second direction DIR2 is connected to the bottom portion 24. In this embodiment, the filler P1 is exposed on the surface of the second side wall portion 22. The end faces of the second side wall portion 22 in the third direction DIR3 and the end faces in the opposite direction to the third direction DIR3 (the third and fourth side faces aligned in the third direction DIR3) do not have to be tapered. Also, the filler P1 does not have to be exposed on the surface of the second side wall portion 22.

[0019] The third side wall 23 is connected to each of the first side wall 21, the bottom 24, the reflector 3, and the optical fiber fixing portion 4. More specifically, the third side wall 23 is located in the third direction DIR3 from the second side wall 22. When viewed in the second direction DIR2, the third side wall 23 is located on the opposite side of the second side wall 22 in the third direction DIR3, with the reflector 3 and the optical fiber fixing portion 4 sandwiched between them. The third side wall 23 has a shape that extends in the first direction DIR1. In this embodiment, the end face of the third side wall 23 in the third direction DIR3 and the end face in the direction opposite to the third direction DIR3 (the third side face and fourth side face aligned in the third direction DIR3) are inclined in a tapered shape. More specifically, when viewed in the first direction DIR1, the angle θ5 formed between the end face of the third side wall portion 23 in the direction opposite to the third direction DIR3 and the third direction DIR3 is an acute angle. When viewed in the first direction DIR1, the angle θ6 formed between the end face of the third side wall portion 23 in the third direction DIR3 and the third direction DIR3 is an obtuse angle. Therefore, the end face of the third side wall portion 23 in the third direction DIR3 and the end face of the third side wall portion 23 in the direction opposite to the third direction DIR3 are not parallel. The third width D3 of the third side wall portion 23 along the third direction DIR3 continuously increases toward the second direction DIR2. Portions of the end face of the third side wall portion 23 in the direction opposite to the third direction DIR3 are connected to the end face of the first side wall portion 21 in the third direction DIR3, the reflector 3, and the optical fiber fixing portion 4. The end face of the third side wall portion 23 in the second direction DIR2 is connected to the bottom portion 24. In this embodiment, the filler P1 is exposed on the surface of the third side wall portion 23. Note that the end face of the third side wall portion 23 in the third direction DIR3 and the end faces in the opposite direction to the third direction DIR3 (the third side face and the fourth side face aligned in the third direction DIR3) do not have to be tapered. Also, the filler P1 does not have to be exposed on the surface of the third side wall portion 23. Note that it is sufficient that at least one of the first width D1 of the first side wall portion 21, the second width D2 of the second side wall portion 22, and the third width D3 of the third side wall portion 23 continuously increase in the second direction DIR2.

[0020] In this embodiment, as shown in Figure 3, at the same position in the second direction DIR2, the first width D1 of the first side wall portion 21, the second width D2 of the second side wall portion 22, and the third width D3 of the third side wall portion 23 are equal to each other.

[0021] As shown in FIG. 1 , the bottom 24 is connected to each of the first side wall 21, the second side wall 22, the third side wall 23, the reflector 3, and the optical fiber fixing portion 4. More specifically, the bottom 24 has a plate shape. In this embodiment, the bottom 24 has a rectangular shape when viewed in the second direction DIR2. A portion of the end face of the bottom 24 in the opposite direction to the second direction DIR2 is connected to each of the end face of the first side wall 21 in the second direction DIR2, the end face of the second side wall 22 in the second direction DIR2, the end face of the third side wall 23 in the second direction DIR2, the reflector 3, and the optical fiber fixing portion 4. Note that the bottom 24 does not have to have a rectangular shape when viewed in the second direction DIR2.

[0022] The optical fiber fixing part 4 fixes each of the five optical fibers 5. The optical fiber fixing part 4 is connected to each of the second side wall part 22, the third side wall part 23, and the bottom part 24. More specifically, the optical fiber fixing part 4 has a plate shape extending in the third direction DIR3. The optical fiber fixing part 4 is located between the second side wall part 22 and the third side wall part 23. The optical fiber fixing part 4 is also connected to each of the second side wall part 22 and the third side wall part 23. More specifically, an end part of the optical fiber fixing part 4 along the direction opposite to the third direction DIR3 is connected to the second side wall part 22. An end part of the optical fiber fixing part 4 along the third direction DIR3 is connected to each of the third side wall parts 23. An end face of the optical fiber fixing part 4 in the second direction DIR2 is connected to the bottom part 24.

[0023] Five V-shaped grooves G are provided on the end face of the optical fiber fixing part 4 in the direction opposite to the second direction DIR2 when viewed in the first direction DIR1. Each of the five grooves G has a shape extending in the first direction DIR1. The five grooves G are aligned in the third direction DIR3. As shown in FIG. 2, five optical fibers 5 are fixed in each of the five grooves G. As a result, the five optical fibers 5 are aligned in the third direction DIR3. Note that grooves G do not necessarily have to be provided on the end face of the optical fiber fixing part 4 in the direction opposite to the second direction DIR2. Furthermore, each of the five grooves G may have a U-shape when viewed in the first direction DIR1. Furthermore, the number of optical fibers 5 is not limited to five, as long as it is plural.

[0024] Each of the five optical fibers 5 has a shape that extends in a first direction DIR1. Each of the five optical fibers 5 has an end face S5 from which light L is emitted. The normal direction of the end face S5 of each of the five optical fibers 5 is the first direction DIR1. Each of the five optical fibers 5 emits light L in the first direction DIR1. The end face S5 of each of the five optical fibers 5 faces the reflector 3 with an interval between them. The light L emitted from any of the five optical fibers 5 travels in the first direction DIR1 and is incident on the reflector 3.

[0025] As shown in FIG. 1 , the reflector 3 is connected to each of the second side wall 22, the third side wall 23, and the bottom 24. The reflector 3 is located between the second side wall 22 and the third side wall 23. The reflector 3 is also connected to each of the second side wall 22 and the third side wall 23. More specifically, an end of the reflector 3 along the opposite direction to the third direction DIR3 is connected to the second side wall 22. The end of the reflector 3 along the third direction DIR3 is also connected to the third side wall 23. As shown in FIG. 2 , the reflector 3 changes the traveling direction of light L incident on the incident surface S11 from the first direction DIR1 to the second direction DIR2. The reflector 3 includes a prism portion 31 and five condenser lens portions 32. The number of condenser lens portions 32 is not limited to five, and may be any plural number.

[0026] The prism portion 31 is connected to each of the second side wall portion 22, the third side wall portion 23, and the bottom portion 24. More specifically, in this embodiment, the prism portion 31 has a right-angled isosceles triangular prism shape extending in the third direction DIR3. The prism portion 31 has a prism portion entrance surface S2, a prism portion reflection surface S3, and a prism portion exit surface S4. Note that the prism portion 31 does not necessarily have to have a right-angled isosceles triangular prism shape.

[0027] The prism portion incident surface S2 is an end surface of the prism portion 31 in the opposite direction to the first direction DIR1. Light L emitted from any of the five optical fibers 5 enters the optical coupler 1 from the prism portion incident surface S2. Therefore, the prism portion incident surface S2 is the incident surface S11 of the optical coupler 1. The light L entering the optical coupler 1 from the prism portion incident surface S2 passes through the inside of the prism portion 31.

[0028] When viewed in the third direction DIR3, the prism portion reflecting surface S3 forms an angle of 135 degrees clockwise with respect to the first direction DIR1. The end of the prism portion reflecting surface S3 opposite the second direction DIR2 is located further in the opposite direction of the first direction DIR1 than the end of the prism portion reflecting surface S3 in the second direction DIR2. The prism portion reflecting surface S3 reflects light L that has passed through the inside of the prism portion 31. As a result, the prism portion reflecting surface S3 changes the traveling direction of the light L from the first direction DIR1 to the second direction DIR2. The prism portion reflecting surface S3 corresponds to the "reflecting surface" of the present invention.

[0029] Five condenser lens sections 32 are provided on the prism section reflecting surface S3. The five condenser lens sections 32 are aligned in the third direction DIR3. The surfaces of the condenser lens sections 32 are aspherical. In this embodiment, the surfaces of the condenser lens sections 32 are ellipsoidal. The condenser lens sections 32 condense light L that passes through the inside of the prism section 31 and travels in the first direction DIR1, while reflecting the light L toward the second direction DIR2. As a result, the condenser lens sections 32 change the traveling direction of the light L from a direction that includes a component of the first direction DIR1 to the second direction DIR2. The surfaces of the condenser lens sections 32 do not have to be ellipsoidal.

[0030] The prism portion exit surface S4 is an end surface of the prism portion 31 in the second direction DIR2. The prism portion exit surface S4 is connected to the bottom portion 24. The prism portion exit surface S4 emits light L that is reflected by the prism portion reflecting surface S3 or the condenser lens portion 32 and passes through the inside of the prism portion 31. The light L emitted from the prism portion exit surface S4 enters the bottom portion 24 from an end surface of the bottom portion 24 in the opposite direction to the second direction DIR2.

[0031] Light L that enters the bottom 24 from an end face of the bottom 24 in the opposite direction to the second direction DIR2 passes through the inside of the bottom 24 and is emitted to the outside of the optical coupler 1 from an end face S1 of the bottom 24 in the second direction DIR2. Therefore, the end face S1 of the bottom 24 in the second direction DIR2 includes the emission surface S12 of the optical coupler 1.

[0032] As shown in FIG. 3 , the region of the end face S1 of the bottom 24 in the second direction DIR2 that overlaps with the reflector 3 when viewed in the second direction DIR2 is defined as region A1. The region of the end face S1 of the bottom 24 in the second direction DIR2 that does not overlap with the reflector 3 when viewed in the second direction DIR2 is defined as region A2. The end face S1 of the bottom 24 in the second direction DIR2 includes both region A1 and region A2. Light L is emitted from region A1 of the bottom 24 to the outside of the optical coupler 1. Therefore, region A1 is the emission surface S12. Region A2 is the mounting surface S22 for mounting the optical coupler 1 on a substrate when the optical coupler 1 is incorporated into a photoelectric conversion circuit module 10 (described later) or the like. The end face S1 of the bottom 24 in the second direction DIR2 includes the emission surface S12 and the mounting surface S22. That is, the mounting surface S22 is in the same plane as the emission surface S12.

[0033] The optical coupler 1 is manufactured by irradiating and exposing a photosensitive glass paste containing glass M1 and a plurality of fillers P1 mixed in the glass M1 with ultraviolet light. Note that the photosensitive glass paste may contain additives such as a dispersant and a light absorber in addition to the glass M1 and the plurality of fillers P1 mixed in the glass M1.

[0034] More specifically, a light-transmitting substrate having a first main surface and a second main surface aligned in the second direction DIR2 is prepared. Next, a photosensitive glass paste is applied to the first main surface of the light-transmitting substrate. Next, a mask is placed on the second main surface of the light-transmitting substrate. Next, ultraviolet light is irradiated onto the second main surface of the light-transmitting substrate, exposing the photosensitive glass paste. This exposes the photosensitive glass paste. Next, the mask is removed from the second main surface of the light-transmitting substrate, and the photosensitive glass paste is developed. More specifically, the photosensitive glass paste and the light-transmitting substrate are immersed in a developer. As a result, if the photosensitive glass paste is negative, the exposed portions of the photosensitive glass paste remain and the unexposed portions are removed. Alternatively, if the photosensitive glass paste is positive, the exposed portions of the photosensitive glass paste are removed and the unexposed portions remain. After development, the photosensitive glass paste and the light-transmitting substrate are washed and dried.

[0035] Finally, the transparent substrate is removed from the developed photosensitive glass paste, and the photosensitive glass paste is hardened. More specifically, the photosensitive glass paste is fired to harden the photosensitive glass paste. Through these steps, the optical coupler 1 is completed.

[0036] [effect] The optical coupler 1 can suppress a decrease in coupling efficiency and also suppress a decrease in the S / N ratio. First, the ability of the optical coupler 1 to suppress a decrease in coupling efficiency will be described.

[0037] The optical coupler 1 is integrally molded from a material containing glass M1 and filler P1 mixed into the glass M1. Therefore, in the optical coupler 1, each component, such as the microlens, optical path changing unit, and V-groove array, can be always positioned in the same position, compared to when each component is a separate member. This makes it easy to maintain positioning accuracy and suppresses a decrease in coupling efficiency.

[0038] The optical coupler 1 also includes a holding unit 2 including a first side wall 21, a second side wall 22 connected to the first side wall 21, and a third side wall 23 connected to the first side wall 21 and located on the opposite side of the second side wall 22 along the third direction DIR3, sandwiching the reflector 3 and the optical fiber fixing unit 4, as viewed in the second direction DIR2. For example, when the temperature of the optical coupler 1 rises due to heat generation from electronic components located around the optical coupler 1, the optical fiber fixing unit 4 and the reflector 3 tend to deform due to thermal expansion. At this time, a force is applied to the optical fiber fixing unit 4 and the reflector 3 along the third direction DIR3 or a direction opposite to the third direction DIR3. In the optical coupler 1, the ends of the optical fiber fixing unit 4 and the reflector 3 along the third direction DIR3 are connected to the third side wall 23. As a result, for example, when the optical fiber fixing part 4 or the reflecting part 3 tries to deform in the third direction DIR3 due to thermal expansion, the deformation of the optical fiber fixing part 4 or the reflecting part 3 in the third direction DIR3 is inhibited by the third side wall part 23. Therefore, the optical fiber fixing part 4 or the reflecting part 3 becomes less likely to deform in the third direction DIR3.

[0039] Furthermore, in the optical coupler 1, the ends of the optical fiber fixing unit 4 and the reflecting unit 3 along the direction opposite to the third direction DIR3 are connected to the second side wall 22. As a result, for example, when the optical fiber fixing unit 4 or the reflecting unit 3 tries to deform in the direction opposite to the third direction DIR3 due to thermal expansion, the deformation of the optical fiber fixing unit 4 or the reflecting unit 3 in the direction opposite to the third direction DIR3 is inhibited by the second side wall 22. Therefore, the optical fiber fixing unit 4 and the reflecting unit 3 are less likely to deform in the direction opposite to the third direction DIR3. As a result, the optical coupler 1 can suppress deformation of the optical fiber fixing unit 4 and the reflecting unit 3 due to thermal expansion. By suppressing deformation of the optical fiber fixing unit 4 and the reflecting unit 3 due to thermal expansion, it is possible to suppress a change in the positional relationship between the optical fiber 5 and the reflecting unit 3 and a decrease in coupling efficiency.

[0040] Next, how the optical coupler 1 can suppress a decrease in the S / N ratio will be described with reference to the drawings. Fig. 4 is a cross-sectional view of the optical coupler 1 and the optical fiber 5, showing how ambient light AL enters the optical coupler 1. Note that in Fig. 4, only a representative filler P1 among the multiple fillers P1 is given a reference symbol. The following description will be given using the first side wall portion 21 as an example, but the same applies to the second side wall portion 22 and the third side wall portion 23.

[0041] For example, when disturbance light AL is incident on the first side wall 21 from the first direction DIR1, part of the disturbance light AL is reflected to the outside of the optical coupler 1 by the end face of the first side wall 21 in the first direction DIR1. However, part of the disturbance light AL enters the inside of the first side wall 21 from the end face of the first side wall 21 in the first direction DIR1. Here, the first width D1 of the first side wall 21 along the first direction DIR1 continuously increases toward the second direction DIR2. In this embodiment, when viewed in the third direction DIR3, the angle θ1 formed between the end face of the first side wall 21 in the first direction DIR1 and the first direction DIR1 is an obtuse angle. Therefore, the direction of travel of ambient light AL entering the interior of the first side wall portion 21 is changed from a direction parallel to the first direction DIR1 to a direction including a component of the second direction DIR2 due to refraction by the end face in the first direction DIR1 of the first side wall portion 21.

[0042] Furthermore, in this embodiment, as viewed in the third direction DIR3, the angle θ2 formed between the end face of the first side wall 21 facing the opposite direction to the first direction DIR1 and the first direction DIR1 is an acute angle. Therefore, the traveling direction of the disturbance light AL traveling inside the first side wall 21 is changed to approach the second direction DIR2 due to refraction by the end face of the first side wall 21 facing the opposite direction to the first direction DIR1. As described above, the optical coupler 1 changes the traveling direction of the disturbance light AL from a direction parallel to the first direction DIR1 to a direction including a component of the second direction DIR2, thereby preventing the disturbance light AL from entering the reflector 3. This prevents the disturbance light AL from mixing with the light L emitted from the optical fiber 5, which would otherwise reduce the S / N ratio. As a result, the optical coupler 1 prevents the S / N ratio from decreasing.

[0043] As described above, the optical coupler 1 can suppress a decrease in coupling efficiency and can further suppress a decrease in the S / N ratio.

[0044] Furthermore, the optical coupler 1 can further suppress a decrease in the S / N ratio. In the following, the first side wall portion 21 will be described as an example, but the same applies to the second side wall portion 22 and the third side wall portion 23.

[0045] In the first side wall 21, the filler P1 is exposed on the surface of the first side wall 21. Therefore, the filler P1 is exposed on an end face of the first side wall 21 in the first direction DIR1 and an end face of the first side wall 21 in the opposite direction to the first direction DIR1. Disturbance light AL incident on the first side wall 21 from the first direction DIR1 is scattered by the filler P1 exposed on the end face of the first side wall 21 in the first direction DIR1. This reduces the intensity of the disturbance light AL entering the inside of the first side wall 21. Furthermore, the disturbance light AL traveling inside the first side wall 21 is scattered by the filler P1 exposed on the end face of the first side wall 21 in the opposite direction to the first direction DIR1. Therefore, the intensity of the disturbance light AL incident on the reflector 3 from the end face of the first side wall 21 in the opposite direction to the first direction DIR1 is further reduced. As a result, the optical coupler 1 can further prevent the disturbance light AL from mixing with the light L emitted from the optical fiber 5, thereby preventing a decrease in the S / N ratio.

[0046] As described above, the optical coupler 1 can suppress a decrease in coupling efficiency and can further suppress a decrease in the S / N ratio.

[0047] [First Modification] [Structure of optical coupler 1a] An optical coupler 1a according to a first modified example of the present invention will be described below with reference to the drawings. Fig. 5 is a cross-sectional view of the optical coupler 1a and an optical fiber 5. Note that in Fig. 5, only a representative filler P1 among the multiple fillers P1 is designated by a reference symbol. Also, in Fig. 5, the second side wall portion 22 and the third side wall portion 23 are omitted. Note that, with regard to the structure of the optical coupler 1a according to the first modified example, only the parts that differ from the structure of the optical coupler 1 according to the first embodiment will be described, and the rest will be omitted.

[0048] In this modification, the end face of the first side wall 21 in the first direction DIR1 and the end faces in the opposite direction to the first direction DIR1 (the first side face and the second side face aligned in the first direction DIR1) are not tapered. More specifically, when viewed in the third direction DIR3, the angle θ2 formed between the end face of the first side wall 21 in the opposite direction to the first direction DIR1 and the first direction DIR1 is a right angle, while the angle θ1 formed between the end face of the first side wall 21 in the first direction DIR1 and the first direction DIR1 is an obtuse angle when viewed in the third direction DIR3. In this modification, as in the optical coupler 1, the first width D1 of the first side wall 21 continuously increases toward the second direction DIR2.

[0049] Note that the end face of the second side wall portion 22 in the third direction DIR3 and the end faces in the opposite direction to the third direction DIR3 (the third side face and the fourth side face aligned in the third direction DIR3) do not have to be tapered. More specifically, as viewed in the first direction DIR1, the angle θ4 formed between the end face of the second side wall portion 22 in the third direction DIR3 and the third direction DIR3 may be a right angle, while the angle θ3 formed between the end face of the second side wall portion 22 in the opposite direction to the third direction DIR3 and the third direction DIR3 may be an acute angle as viewed in the first direction DIR1. Even in this case, similar to the optical coupler 1, the second width D2 of the second side wall portion 22 continuously increases toward the second direction DIR2.

[0050] Note that the end face of the third side wall portion 23 in the third direction DIR3 and the end faces in the direction opposite to the third direction DIR3 (the third side face and the fourth side face aligned in the third direction DIR3) do not have to be tapered. More specifically, as viewed in the first direction DIR1, the angle θ5 formed between the end face of the third side wall portion 23 in the direction opposite to the third direction DIR3 and the third direction DIR3 may be a right angle, while the angle θ6 formed between the end face of the third side wall portion 23 in the third direction DIR3 and the third direction DIR3 may be an obtuse angle as viewed in the first direction DIR1. Even in this case, as in the optical coupler 1, the third width D3 of the third side wall portion 23 continuously increases toward the second direction DIR2.

[0051] The optical coupler 1a as described above also has the same effect as the optical coupler 1.

[0052] [Second Modification] [Structure of optical coupler 1b] An optical coupler 1b according to a second modified example of the present invention will be described below with reference to the drawings. Fig. 6 is a cross-sectional view of the optical coupler 1b and an optical fiber 5. Note that in Fig. 6, only a representative filler P1 among the multiple fillers P1 is designated by a reference symbol. Also, in Fig. 6, the second side wall portion 22 and the third side wall portion 23 are omitted. Note that, with regard to the structure of the optical coupler 1b according to the second modified example, only the parts that differ from the structure of the optical coupler 1 according to the first embodiment will be described, and the rest will be omitted.

[0053] In this modification, the end face of the first side wall 21 in the first direction DIR1 and the end face in the opposite direction to the first direction DIR1 (the first side face and the second side face aligned in the first direction DIR1) are not tapered. More specifically, when viewed in the third direction DIR3, the angle θ1 formed between the end face of the first side wall 21 in the first direction DIR1 and the first direction DIR1 is a right angle, while the angle θ2 formed between the end face of the first side wall 21 in the opposite direction to the first direction DIR1 and the first direction DIR1 is an acute angle when viewed in the third direction DIR3. In this modification, as in the optical coupler 1, the first width D1 of the first side wall 21 continuously increases toward the second direction DIR2.

[0054] Note that the end face of the second side wall portion 22 in the third direction DIR3 and the end faces in the opposite direction to the third direction DIR3 (the third side face and the fourth side face aligned in the third direction DIR3) do not have to be tapered. More specifically, as viewed in the first direction DIR1, the angle θ3 formed between the end face of the second side wall portion 22 in the opposite direction to the third direction DIR3 and the third direction DIR3 may be a right angle, while the angle θ4 formed between the end face of the second side wall portion 22 in the third direction DIR3 and the third direction DIR3 may be an obtuse angle as viewed in the first direction DIR1. Even in this case, similar to the optical coupler 1, the second width D2 of the second side wall portion 22 continuously increases toward the second direction DIR2.

[0055] Note that the end face of the third side wall portion 23 in the third direction DIR3 and the end faces in the direction opposite to the third direction DIR3 (the third side face and the fourth side face aligned in the third direction DIR3) do not have to be tapered. More specifically, as viewed in the first direction DIR1, the angle θ6 formed between the end face of the third side wall portion 23 in the third direction DIR3 and the third direction DIR3 may be a right angle, while the angle θ5 formed between the end face of the third side wall portion 23 in the direction opposite to the third direction DIR3 and the third direction DIR3 may be an acute angle. In this case, as in the optical coupler 1, the third width D3 of the third side wall portion 23 continuously increases toward the second direction DIR2.

[0056] The optical coupler 1b as described above also has the same effect as the optical coupler 1.

[0057] [Third Modification] [Structure of optical coupler 1c] An optical coupler 1c according to a third modified example of the present invention will be described below with reference to the drawings. Fig. 7 is a plan view of the optical coupler 1c as viewed in the opposite direction to the second direction DIR2. Regarding the structure of the optical coupler 1c according to the third modified example, only the parts that differ from the structure of the optical coupler 1 according to the first embodiment will be described, and the rest will be omitted.

[0058] In this modified example, at the same position in the second direction DIR2, the second width D2 of the second side wall portion 22 is wider than the first width D1 of the first side wall portion 21. Furthermore, the third width D3 of the third side wall portion 23 is wider than the first width D1 of the first side wall portion 21. Note that, in this modified example, at the same position in the second direction DIR2, the second width D2 of the second side wall portion 22 is equal to the third width D3 of the third side wall portion 23. Note that, at the same position in the second direction DIR2, the second width D2 of the second side wall portion 22 does not have to be equal to the third width D3 of the third side wall portion 23.

[0059] In other words, when viewed in the second direction DIR2, the longitudinal direction of the optical coupler 1c is the first direction DIR1. When viewed in the second direction DIR2, the lateral direction of the optical coupler 1c is the third direction DIR3. The longitudinal direction and the lateral direction of the optical coupler 1c are perpendicular to each other. At the same position in the second direction DIR2, the widths of the sidewall portions having a shape extending in the longitudinal direction (first direction DIR1) of the optical coupler 1c (the second width D2 of the second sidewall portion 22 and the third width D3 of the third sidewall portion 23) are wider than the widths of the sidewall portions having a shape extending in the lateral direction (third direction DIR3) of the optical coupler 1c (the first width D1 of the first sidewall portion 21).

[0060] When viewed in the second direction DIR2, the longitudinal direction of the optical coupler 1c is the third direction DIR3 and the lateral direction of the optical coupler 1c is the first direction DIR1, at the same position in the second direction DIR2, the width of the side wall portion having a shape extending in the longitudinal direction (third direction DIR3) of the optical coupler 1c (first width D1 of the first side wall portion 21) should be wider than the width of the side wall portion having a shape extending in the lateral direction (first direction DIR1) of the optical coupler 1c (second width D2 of the second side wall portion 22 and third width D3 of the third side wall portion 23).

[0061] The optical coupler 1c described above also achieves the same effects as the optical coupler 1. Furthermore, the optical coupler 1c can effectively suppress a decrease in coupling efficiency. The following description will be given taking as an example a case where, as viewed in the second direction DIR2, the longitudinal direction of the optical coupler 1c is the first direction DIR1 and the lateral direction of the optical coupler 1c is the third direction DIR3, but the same applies to a case where, as viewed in the second direction DIR2, the longitudinal direction of the optical coupler 1c is the third direction DIR3 and the lateral direction of the optical coupler 1c is the first direction DIR1.

[0062] When the side wall portion having a shape extending in the short direction of the optical coupler 1c is deformed due to thermal expansion, the positional relationship between the optical fiber 5 and the reflector 3 changes more, and the coupling efficiency decreases more than when the side wall portion having a shape extending in the longitudinal direction of the optical coupler 1c is deformed due to thermal expansion.

[0063] Therefore, according to the optical coupler 1c, at the same position in the second direction DIR2, the second width D2 of the second side wall portion 22 is wider than the first width D1 of the first side wall portion 21. This allows the second side wall portion 22 to have a higher rigidity than the first side wall portion 21. Furthermore, the third width D3 of the third side wall portion 23 is wider than the first width D1 of the first side wall portion 21. This allows the third side wall portion 23 to have a higher rigidity than the first side wall portion 21. By increasing the rigidity of the third side wall portion 23 connected to the first side wall portion 21, the third side wall portion 23, which has high rigidity, can inhibit deformation of the first side wall portion 21 in the third direction DIR3 due to thermal expansion. In other words, the side wall portion, which has a shape extending in the longitudinal direction of the optical coupler 1c and has high rigidity, can inhibit deformation of the optical coupler 1c in the lateral direction due to thermal expansion of the first side wall portion 21. Therefore, the first side wall portion 21 is less likely to deform in the short-side direction of the optical coupler 1c.

[0064] Furthermore, by increasing the rigidity of the second side wall portion 22 connected to the first side wall portion 21, deformation in the opposite direction to the third direction DIR3 due to thermal expansion of the first side wall portion 21 can be inhibited by the highly rigid second side wall portion 22. Therefore, the optical fiber fixing portion 4, the reflecting portion 3, and the first side wall portion 21 are less likely to deform in the short-side direction of the optical coupler 1c.

[0065] As a result, the optical coupler 1c can effectively prevent deformation due to thermal expansion of the first side wall 21. By preventing deformation due to thermal expansion of the first side wall 21, which has a shape extending in the short direction of the optical coupler 1c, it is possible to prevent further changes in the positional relationship between the optical fiber 5 and the reflector 3, and effectively prevent a decrease in coupling efficiency.

[0066] [Fourth Variation] [Structure of photoelectric conversion circuit module 10] Hereinafter, a photoelectric conversion circuit module 10 according to a fourth modified example will be described with reference to the drawings. Fig. 8 is a perspective view of the photoelectric conversion circuit module 10 and an optical fiber 5. Note that in Fig. 8, reference symbols are assigned only to representative optical couplers 1, optical fibers 5, and optical waveguides OW among the plurality of optical couplers 1, the plurality of optical fibers 5, and the plurality of optical waveguides OW. Fig. 9 is an AA cross-sectional view of the photoelectric conversion circuit module 10 and the optical fiber 5. Note that in Fig. 9, reference symbols are assigned only to representative fillers P1 among the plurality of fillers P1.

[0067] As shown in FIG. 8 , the photoelectric conversion circuit module 10 includes a plurality of optical couplers 1, a substrate 11, and a photoelectric conversion circuit 12. The plurality of optical couplers 1 and the photoelectric conversion circuit 12 are mounted on the substrate 11. The photoelectric conversion circuit 12 is disposed at the center of the substrate 11 when viewed in the second direction DIR2. The plurality of optical couplers 1 are disposed around the photoelectric conversion circuit 12 when viewed in the second direction DIR2. Each of the plurality of optical fibers 5 is fixed to the optical fiber fixing portion 4 of each of the plurality of optical couplers 1. The number of optical couplers 1 is not limited to a plurality, and may be one. Furthermore, the photoelectric conversion circuit 12 does not have to be disposed at the center of the substrate 11 when viewed in the second direction DIR2. Furthermore, the plurality of optical couplers 1 do not have to be disposed around the photoelectric conversion circuit 12 when viewed in the second direction DIR2. Moreover, the photoelectric conversion circuit module 10 may include, instead of the optical coupler 1, an optical coupler 1a, an optical coupler 1b, or an optical coupler 1c.

[0068] The substrate 11 has a plate shape with two main surfaces aligned in the second direction DIR2. However, as shown in FIG. 9, an optical waveguide OW and a mirror M are provided inside the substrate 11. The optical waveguide OW is provided between the photoelectric conversion circuit 12 and each of the multiple optical couplers 1. The mirror M is provided in the second direction DIR2 from the reflecting portion 3. The light L emitted from the photoelectric conversion circuit 12 passes through the optical waveguide OW.

[0069] The optical couplers 1 are mounted on one of the two main surfaces of the substrate 11 that is located in the opposite direction to the second direction DIR2. More specifically, the mounting surface S22 is mounted on the other of the two main surfaces of the substrate 11 that is located in the opposite direction to the second direction DIR2.

[0070] The photoelectric conversion circuit 12 is mounted on one of the two main surfaces of the substrate 11 that is located in the opposite direction to the second direction DIR2. The photoelectric conversion circuit 12 converts the light emitted from the optical coupler 1 into an electric signal, or converts the electric signal into light that enters the optical coupler 1. A case where the photoelectric conversion circuit 12 converts the light emitted from the optical coupler 1 into an electric signal will be described.

[0071] Light L emitted from any of the five optical fibers 5 enters the incident surface S11 of the optical coupler 1, has its traveling direction changed by the optical coupler 1 from a first direction DIR1 to a second direction DIR2, and is emitted from the exit surface S12 of the optical coupler 1. The light L emitted from the exit surface S12 of the optical coupler 1 travels in the second direction DIR2 within the optical waveguide OW. The light L traveling in the second direction DIR2 within the optical waveguide OW is reflected by the mirror M. As a result, the traveling direction of the light L is changed from the second direction DIR2 to the first direction DIR1. The light L then enters the photoelectric conversion circuit 12. The photoelectric conversion circuit 12 converts the light L incident on the photoelectric conversion circuit 12 into an electrical signal.

[0072] The photoelectric conversion circuit module 10 as described above also provides the same effects as the optical coupler 1.

[0073] [Fifth Variation] [Structure of photoelectric conversion circuit module 10a] A photoelectric conversion circuit module 10a according to the fifth modification will be described below with reference to the drawings. Fig. 10 is a perspective view of the photoelectric conversion circuit module 10a and an optical fiber 5. In Fig. 10, reference symbols are assigned only to representative optical couplers 1 and optical fibers 5 among the plurality of optical couplers 1 and the plurality of optical fibers 5. Regarding the photoelectric conversion circuit module 10a according to the fifth modification, only the differences from the photoelectric conversion circuit module 10 according to the fourth modification will be described, and the rest will be omitted.

[0074] The photoelectric conversion circuit module 10a differs from the photoelectric conversion circuit module 10 in that the substrate 11 is a semiconductor substrate and that the substrate 11 includes a plurality of light emitting portions 13. The number of light emitting portions 13 is not limited to a plurality, and may be one.

[0075] Each of the plurality of light emitting units 13 is, for example, a surface light emitting element formed on one of the two main surfaces of the substrate 11, the main surface located in the opposite direction to the second direction DIR2. Each of the plurality of light emitting units 13 is, for example, a VCSEL (Vertical Cavity Surface Emitting Laser). Each of the plurality of light emitting units 13 emits light L based on an electrical signal generated by the photoelectric conversion circuit 12. The light L emitted from each of the plurality of light emitting units 13 is incident on each of the plurality of optical fibers 5 via each of the plurality of optical couplers 1.

[0076] The photoelectric conversion circuit module 10a as described above also provides the same effects as the photoelectric conversion circuit module 10.

[0077] [Sixth Modification] [Structure of optical transceiver 100] The optical transceiver 100 will be described below with reference to the drawings. Fig. 11 is a perspective view of the optical transceiver 100 and the optical fibers 5. Note that in Fig. 11, only a representative optical fiber 5 among the five optical fibers 5 is designated by a reference symbol. Note that for the optical transceiver 100 according to the sixth modification, only the differences from the photoelectric conversion circuit module 10a according to the fifth modification will be described, and the rest will be omitted.

[0078] The optical transceiver 100 differs from the photoelectric conversion circuit module 10a in that the optical transceiver 100 has one optical coupler 1 and one light emitting unit 13.

[0079] The light L emitted by the light emitting unit 13 enters each of the five optical fibers 5 via the optical coupler 1, or the light L emitted from each of the five optical fibers 5 enters the photoelectric conversion circuit 12 via the optical coupler 1.

[0080] The optical transceiver 100 as described above also provides the same effects as the photoelectric conversion circuit module 10a.

[0081] [Other embodiments] The optical couplers according to the present invention are not limited to the optical coupler 1, the optical coupler 1a, the optical coupler 1b, and the optical coupler 1c, and may be modified within the scope of the present invention. In addition, the structures of the optical coupler 1, the optical coupler 1a, the optical coupler 1b, and the optical coupler 1c may be arbitrarily combined.

[0082] The photoelectric conversion circuit module according to the present invention is not limited to the photoelectric conversion circuit module 10 and the photoelectric conversion circuit module 10a, and can be modified within the scope of the present invention. Furthermore, the structures of the photoelectric conversion circuit module 10 and the photoelectric conversion circuit module 10a may be combined in any manner.

[0083] The optical transceiver according to the present invention is not limited to the optical transceiver 100, and can be modified within the scope of the gist thereof.

[0084] The present invention has the following configuration.

[0085] (1) An optical coupler integrally formed from a material including glass and a filler mixed in the glass, an optical fiber fixing portion that fixes each of a plurality of optical fibers that emit light in a first direction; a reflector that changes the traveling direction of the light emitted from any one of the plurality of optical fibers from the first direction to a second direction perpendicular to the first direction; a holder that holds the optical fiber fixing portion and the reflector, respectively; It is equipped with The holding portion is a first sidewall portion having a shape extending in a third direction perpendicular to the first direction and the second direction; a second side wall portion connected to the first side wall portion and having a shape extending in the first direction; a third side wall portion that is connected to the first side wall portion and has a shape that extends in the first direction, and that is located on an opposite side of the second side wall portion in the third direction, with the optical fiber fixing portion and the reflecting portion sandwiched between them, as viewed in the second direction; It contains an end portion of the optical fiber fixing portion and an end portion of the reflecting portion along the third direction are connected to the second side wall portion and the third side wall portion, respectively; At least one of a width of the first side wall portion along the first direction, a width of the second side wall portion along the third direction, and a width of the third side wall portion along the third direction continuously increases toward the second direction. Optical coupler.

[0086] (2) the filler is exposed on the surface of the first side wall portion, the second side wall portion, or the third side wall portion; The optical coupler according to (1).

[0087] (3) The first side surface and the second side surface of the first sidewall portion aligned in the first direction are inclined in a tapered shape. Alternatively, a third side surface and a fourth side surface of the second side wall portion or the third side wall portion aligned in the third direction are inclined in a tapered shape. An optical coupler according to (1) or (2).

[0088] (4) the first direction is a longitudinal direction of the optical coupler when viewed in the second direction, the third direction is a short-side direction of the optical coupler when viewed in the second direction, At the same position in the second direction, the width of the second side wall portion in the third direction and the width of the third side wall portion in the third direction are wider than the width of the first side wall portion in the first direction. An optical coupler according to any one of (1) to (3).

[0089] (5) the third direction is a longitudinal direction of the optical coupler when viewed in the second direction, the first direction is a short-side direction of the optical coupler when viewed in the second direction, At the same position in the second direction, the width of the first side wall portion in the first direction is wider than the width of the second side wall portion in the third direction and the width of the third side wall portion in the third direction. An optical coupler according to any one of (1) to (3).

[0090] (6) An optical coupler according to any one of (1) to (5), A substrate; a photoelectric conversion circuit mounted on the substrate, The photoelectric conversion circuit converts an electrical signal into light incident on the optical coupler, or converts light emitted from the optical coupler into an electrical signal. Photoelectric conversion circuit module.

[0091] (7) the substrate is a semiconductor substrate and includes a light emitting portion that emits light, the optical coupler is mounted on the substrate; (6) A photoelectric conversion circuit module according to (6).

[0092] (8) (1) An optical coupler according to any one of (1) to (5), Optical transceiver. [Explanation of symbols]

[0093] 1,1a,1b,1c: Optical coupler 2: Holding part 3:Reflector 4: Optical fiber fixing part 5: Optical fiber 10, 10a: Photoelectric conversion circuit module 11: Circuit board 12: Photoelectric conversion circuit 13: Light output section 21: First side wall portion 22: Second side wall portion 23: Third side wall 24: Bottom 31: Prism part 32: Condenser lens section 100: Optical transceiver A1,A2:Area AL: ambient light D1: 1st width D2: 2nd width D3: Third width DIR1: 1st direction DIR2:Second direction DIR3: Third direction G:Groove L:Light M: Mirror M1: Glass OW: Optical waveguide P1: Filler S1, S5: End face S11:Incidence surface S12: Output surface S2: Prism entrance surface S22: Mounting surface S3: Prism part reflective surface S4: Prism part exit surface

Claims

1. An optical coupler integrally formed from a material including glass and a filler mixed in the glass, an optical fiber fixing portion that fixes each of a plurality of optical fibers that emit light in a first direction; a reflector that changes the traveling direction of the light emitted from any one of the plurality of optical fibers from the first direction to a second direction perpendicular to the first direction; a holder that holds the optical fiber fixing portion and the reflector, respectively; It is equipped with The holding portion is a first sidewall portion having a shape extending in a third direction perpendicular to the first direction and the second direction; a second side wall portion connected to the first side wall portion and having a shape extending in the first direction; a third side wall portion connected to the first side wall portion and having a shape extending in the first direction, the third side wall portion being located on an opposite side of the second side wall portion in the third direction with the optical fiber fixing portion and the reflecting portion interposed therebetween when viewed in the second direction; It contains an end portion of the optical fiber fixing portion and an end portion of the reflecting portion along the third direction are connected to the second side wall portion and the third side wall portion, respectively; At least one of a width of the first side wall portion along the first direction, a width of the second side wall portion along the third direction, and a width of the third side wall portion along the third direction continuously increases toward the second direction, a first side surface and a second side surface of the first sidewall portion aligned in the first direction are tapered with respect to the first direction; a third side surface and a fourth side surface of the second side wall portion and the third side wall portion, which are aligned in the third direction, are inclined in a tapered shape with respect to the third direction; The traveling direction of ambient light entering the inside of the first side wall portion is refracted by the first side surface or the second side surface. Optical coupler.

2. An optical coupler integrally molded from a material containing glass and a filler mixed into the glass, an optical fiber fixing portion that fixes each of a plurality of optical fibers that emit light in a first direction; a reflector that changes the traveling direction of the light emitted from any one of the plurality of optical fibers from the first direction to a second direction perpendicular to the first direction; a holder that holds the optical fiber fixing portion and the reflector, respectively; It is equipped with The holding portion is a first sidewall portion having a shape extending in a third direction perpendicular to the first direction and the second direction; a second side wall portion connected to the first side wall portion and having a shape extending in the first direction; a third side wall portion connected to the first side wall portion and having a shape extending in the first direction, the third side wall portion being located on an opposite side of the second side wall portion in the third direction with the optical fiber fixing portion and the reflecting portion interposed therebetween when viewed in the second direction; It contains an end portion of the optical fiber fixing portion and an end portion of the reflecting portion along the third direction are connected to the second side wall portion and the third side wall portion, respectively; At least one of a width of the first side wall portion along the first direction, a width of the second side wall portion along the third direction, and a width of the third side wall portion along the third direction continuously increases toward the second direction, the filler is exposed so as to protrude from a surface of a first side surface and a second side surface of the first side wall portion aligned in the first direction, the filler is exposed so as to protrude from the surface on a third side surface and a fourth side surface of the second side wall portion and the third side wall portion, the third side surface and the fourth side surface being aligned in the third direction; Optical coupler.

3. The filler is exposed so as to protrude from the surface of the first side wall portion, the second side wall portion, or the third side wall portion.

2. The optical coupler of claim 1.

4. the first direction is a longitudinal direction of the optical coupler when viewed in the second direction, the third direction is a short-side direction of the optical coupler when viewed in the second direction, At the same position in the second direction, a width of the second side wall portion along the third direction and a width of the third side wall portion along the third direction are wider than a width of the first side wall portion along the first direction.

4. The optical coupler according to claim 1.

5. the third direction is a longitudinal direction of the optical coupler when viewed in the second direction, the first direction is a short-side direction of the optical coupler when viewed in the second direction, At the same position in the second direction, the width of the first side wall portion in the first direction is wider than the width of the second side wall portion in the third direction and the width of the third side wall portion in the third direction.

4. The optical coupler according to claim 1.

6. an optical coupler according to any one of claims 1 to 3; A substrate; a photoelectric conversion circuit mounted on the substrate, The photoelectric conversion circuit converts an electrical signal into light incident on the optical coupler, or converts light emitted from the optical coupler into an electrical signal. Photoelectric conversion circuit module.

7. the substrate is a semiconductor substrate and includes a light emitting portion that emits light, the optical coupler is mounted on the substrate; The photoelectric conversion circuit module according to claim 6 .

8. An optical coupler according to any one of claims 1 to 3, Optical transceiver.

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