JP7331508B2 - Optical module and method for manufacturing optical module - Google Patents

Description

The present invention relates to an optical module and an optical module manufacturing method.

In recent years, we are approaching the limits of high-speed transmission and large-capacity signal transmission technology using only electrical wiring. Attention has been paid to the development of signal transmission technology that utilizes

Signal transmission utilizing this optical wiring requires an optical module that converts optical signals and electrical signals. 2. Description of the Related Art A general optical module uses a photoelectric element such as a small, high-performance surface emitting element or a surface light receiving element, and an optical waveguide such as an optical fiber. Since the optical axis of a surface light emitting device or a surface light receiving device is perpendicular to the surface of the device, the optical waveguide must be accurately positioned and mounted perpendicular to the surface of the device. In addition, miniaturization for space saving is also required. In the following description, photoelectric elements refer to surface emitting elements and surface light receiving elements unless otherwise specified.

For example, Japanese Patent Laid-Open No. 2002-200002 discloses a technique that meets the above requirements. In Patent Document 1, a guide called a ferrule that vertically holds an optical fiber is fixed to a flexible substrate on which a photoelectric device is mounted. After holding the optical fiber, the photoelectric device is aligned and fixed to the optical fiber. . In addition, the flexible substrate is bent at right angles near the photoelectric element, an extension is provided in the direction from the tip of the optical fiber to the tip, and other components are mounted on the extension to reduce the area in the width direction of the optical fiber. there is

Further, Patent Document 2 discloses an optical module that does not require a three-dimensional guide. In this technique, a V-shaped groove is provided in the wiring layer of the flexible substrate, and the flexible substrate is bent at right angles at the V-shaped groove. Then, the photoelectric element is mounted on the vertical surface of the flexible substrate, and the optical fiber is mounted on the horizontal surface of the flexible substrate. Also, on the horizontal surface, a groove for locking the optical fiber is formed using a wiring pattern to position the optical fiber. Further, the position of the optical fiber is finely adjusted by alignment work, and the position of the photoelectric element and the optical fiber is aligned. In Patent Document 2, since the flexible substrate extends in the direction along the optical fiber, the size of the optical fiber in the longitudinal direction can also be reduced.

JP 2014-137584 A JP 2017-049479 A

As described above, in the technique of Patent Document 1, it is necessary to prepare a three-dimensional guide separately from the flexible substrate. Moreover, since the substrate extends in the direction from the tip of the optical fiber, there is a problem that the entire length is increased. Moreover, the technique of Patent Document 2 has a problem that manufacturing is difficult. In Patent Document 2, a wiring layer of a flexible substrate is provided with a V-shaped groove by dicing, and the flexible substrate is bent vertically. However, the dimensional accuracy of dicing and bending is generally lower than the required accuracy of optical axis positioning. For this reason, the position of the photoelectric element determined by bending may exceed the range in which alignment with the optical fiber is possible, resulting in a decrease in yield.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an optical module that is easy to manufacture and that can be miniaturized.

In order to solve the above problems, an optical module has a printed circuit board having a substrate and wiring, a photoelectric element, and an optical waveguide. The printed circuit board has a first concave portion against which the end face of the optical waveguide abuts, a second concave portion provided inside the first concave portion and deeper than the first concave portion, and an extending portion extending to the outside of the first concave portion. have. The photoelectric element is mounted in the second recess and connected to the wiring such that its top surface is lower than the bottom surface of the first recess. The optical waveguide is fixed with one end abutting against the bottom surface of the first recess. The extension of the printed circuit board extends along the optical waveguide.

An advantage of the present invention is that it is possible to provide an optical module that is easy to manufacture and can be miniaturized.

1 is a cross-sectional view showing an optical module according to a first embodiment; FIG. FIG. 5 is a perspective partial cross-sectional view showing an optical module of a second embodiment; FIG. 10 is a cross-sectional view of the vicinity of the cavity of the optical module of the second embodiment; FIG. 11 is a perspective view showing an example of a waveguide used in the third embodiment; 8A and 8B are a plan view and a cross-sectional view showing members used in the optical module of the third embodiment; FIG. FIG. 11 is a cross-sectional view of the vicinity of the cavity of the optical module of the third embodiment; It is a cross-sectional view showing the first part of the optical module manufacturing method of the fourth embodiment. It is a cross-sectional view showing the second part of the optical module manufacturing method of the fourth embodiment. FIG. 14 is a cross-sectional view showing the third part of the optical module manufacturing method of the fourth embodiment; It is sectional drawing which shows the 4th part of the optical module manufacturing method of 4th Embodiment. It is sectional drawing which shows the 5th part of the optical module manufacturing method of 4th Embodiment. It is a sectional view showing a cavity structure of a fifth embodiment. FIG. 14 is a cross-sectional view showing the vicinity of the cavity of the optical module of the fifth embodiment; FIG. 12 is a cross-sectional view showing another cavity structure of the fifth embodiment; FIG. 14 is a cross-sectional view showing the vicinity of another cavity of the optical module of the fifth embodiment; FIG. 11 is a perspective partial cross-sectional view showing an optical module of a sixth embodiment;

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. However, the embodiments described below are technically preferable for carrying out the present invention, but the scope of the invention is not limited to the following. In addition, the same number may be attached|subjected to the same component of each drawing, and description may be abbreviate|omitted.

(First embodiment)
FIG. 1 is a plan view showing the optical module of this embodiment. The optical module comprises a printed circuit board 1 having a base material 1a and wiring 1b, a photoelectric element 2 and an optical waveguide 3. As shown in FIG.

The flexible substrate 1 includes a first concave portion 1c against which the end surface of the optical waveguide 3 abuts, a second concave portion 1d provided inside the first concave portion 1c and deeper than the first concave portion 1c, and an outer side of the first concave portion 1c. and an extension portion 1e that extends to the

The photoelectric element 2 is mounted in the second recess 1d so that its top surface is lower than the bottom surface of the first recess 1c and is connected to the wiring 1b.

The optical waveguide 3 is fixed with one end abutting against the bottom surface of the first recess 1c.

The extension 1 e of the printed circuit board 1 extends along the optical waveguide 3 .

With the above configuration, positioning of the optical waveguide can be easily performed. In addition, since the extending portion is arranged in the direction along the optical waveguide, the dimensions of the optical module are small both in the width direction and the length direction of the optical waveguide. Therefore, according to this embodiment, it is possible to provide an optical module that is easy to manufacture and can be miniaturized.

(Second embodiment)
FIG. 2 is a perspective partial cross-sectional view of the optical module 100 of this embodiment. The optical module 100 has an FPC 10 , a photoelectric element 20 and an optical waveguide 30 . Here, FPC is an abbreviation for Flexible Printed Circuits.

The FPC 10 has a base material 11 and wirings 12 and has high flexibility. It has a cavity structure consisting of a first cavity 13 and a second cavity 14 on one side. The first cavity 13 is a concave portion recessed from the surface of the FPC 10 . The second cavity 14 is located inside the first cavity 13 and is a recess that is deeper than the first cavity 13 . The wiring 12 is exposed on the bottom surface of the second cavity 14 so that it can be connected to the photoelectric element 20 . An extending portion 15 is provided outside the first cavity 13 of the FPC 10 . In the optical module 100 , the FPC 10 is adhesively fixed so that the extension portion 15 covers the optical waveguide 11 while being bent in a U-shape or U-shape so that the cavity structure faces inside. Further, in the example of FIG. 2, an electrode 16 is provided on the outer edge of the FPC 10 .

In the second cavity 14, the photoelectric element 20 is mounted on the FPC 10 via bumps (not shown), and the photoelectric function part (light emitting part or light receiving part) is mounted in a state of being exposed to the optical waveguide 30 side. . Incidentally, the bump connecting portion is protected with an underfill resin.

A surface emitting laser (VCSEL), a photodiode (PD), a phototransistor (PTr), or the like can be applied to the photoelectric element 20 . VCSEL is an abbreviation for Vertical Cavity Surface Emitting LASER, PD is an abbreviation for Photodiode, and PTr is an abbreviation for Phototransistor. An electrode arranged on the opposite surface is electrically connected to the optical function portion (light emitting portion or light receiving portion) of the photoelectric element 20 via a through hole or a via. As a mounting form of the photoelectric element 20, a flip-chip mounting method using bumps or a wire bonding method can be adopted. In the case of the wire bonding method, the photoelectric element has the optical function part and the electrode formed on the same surface. The photoelectric element is mounted in the second cavity 14 with the optical functional part facing upward, and the electrode of the optical functional part and the electrode connected to the wiring 12 are electrically connected by gold wires or the like. .

The optical waveguide 30 has a core 31 and a clad 32 and has a function of propagating light through the core 31 . FIG. 3 shows an enlarged view of the cavity portion. As shown in FIG. 3 , the optical waveguide 30 is positioned in the thickness direction of the FPC 10 by abutting the end surface 30 ′ of the optical waveguide 30 against the bottom surface 13 ′ of the first cavity 13 . By inserting the end portion of the optical waveguide 30 into the first cavity 13, the position of the optical waveguide 30 in the longitudinal direction of the FPC 10 is positioned with a predetermined margin. End face 30' is, of course, where light exits or enters. Due to the above positioning, the distance between the core 31 exposed at the end surface 30' of the optical waveguide 30 and the optically functional portion of the photoelectric element 20 is kept at a predetermined value. Here, the dimensional tolerance of the inter-surface distance between the bottom surface 13' of the first cavity 13 and the bottom surface 14' of the second cavity 14 of the FPC 10 is preferably ±several tens of micrometers or less. Also, the side surface of the first cavity 13 and the side surface of the optical waveguide 30 are adhesively fixed with an adhesive 52 . Also, the inside of the second cavity 14 is filled with a refractive index matching adhesive 53 . The refractive index matching adhesive 53 has a function of preventing a refractive index difference between the core 31, the photoelectric element and the gap. Moreover, since the end surface 30 ′ of the optical waveguide 30 is connected to the photoelectric element 20 and the bottom surface 14 ′ of the second cavity 14 , the optical waveguide 30 is fixed firmly. Note that the adhesive 52 may be the same as the refractive index matching adhesive 53 . Also, if the optical coupling loss is negligible even if there is air between the core 31 and the photoelectric element 20, the second cavity 14 may not be filled with the refractive index matching adhesive 53. FIG.

As described above, the position of the optical waveguide 30 in the in-plane direction of the FPC 10 has a predetermined margin. This is to precisely position the photoelectric element 20 and the optical waveguide 30 using an optical monitor or the like before the adhesive 52 is cured. By curing the adhesive 52 in a state in which precise position adjustment has been performed, accurate optical axis alignment between the photoelectric element 20 and the optical waveguide 30 can be performed. Details of the alignment process will be described later.

Here, returning to FIG. 2, the configuration of the optical module 100 will be described again. A signal processing IC 40 and an electronic component 41 are mounted inside the extension portion 15 of the FPC 10 . The surroundings of these are covered with mold resin 42 . In this example, the upper surface of the mold resin 42 is made flat. Here, IC is an abbreviation for Integrated Circuit.

A reinforcing plate 50 for reinforcing the mechanical strength of the optical waveguide 30 is adhered to the side surface of the optical waveguide 30 . Further, the end of the reinforcing plate 50 may also be adhered to the FPC 10 outside the first cavity 13 .

An adhesive sheet 51 is adhered to the surface of the reinforcing plate 50 opposite to the optical waveguide. The surface of the adhesive sheet 51 opposite to the reinforcing plate 50 is adhered to the molding resin 42 . This bonding maintains the shape in which the extension part 15 is arranged along the optical waveguide 30 while the FPC 10 is bent in a U-shape or a U-shape.

In the above description, the structure using the reinforcing plate 50 is shown, but the structure without the reinforcing plate 50 may be adopted as long as the fixing strength of the optical waveguide 30 to the FPC 10 can be secured. If the reinforcing plate 50 is not provided, the side surface of the optical waveguide 30 and the upper surface of the mold resin 42 may be adhered.

In the example of FIG. 2, an electronic component 41 such as a signal processing IC 40 and a capacitor is mounted on the extended portion 15 of the FPC 10 . A signal processing IC 40 and an electronic component 41 are connected to the wiring 12 . For example, the signal processing IC 40 can be mounted face-down using bumps, and the bump connection portions can be protected with an underfill resin. Then, the entire signal processing IC 40 including the surroundings of the underfill resin can be protected by the molding resin 42 . In the example of FIG. 2, the signal processing IC 40 is mounted face-down using bumps. may be taken. In this case, the entire signal processing IC 40 including the wire connection portion may be protected by the molding resin 42 .

As with the signal processing IC 40 , the surface-mounted electronic component 41 can be mounted inside the extension portion 15 using solder, for example. The entire electronic component 41 including the solder joints can be protected by the mold resin 42 .

As described above, in the optical module 100 of this embodiment, the optical waveguide 30 and the photoelectric element 20 can be accurately positioned by a simple process. In addition, since the FPC 10 extends along the optical waveguide 30, the optical module 100 can be miniaturized both in the width direction and the length direction of the optical waveguide 30. FIG. In addition, since the distance between the end surface (incident end surface or output end surface) of the optical waveguide and the optical function portion (light emitting surface or light receiving surface) of the photoelectric element can be made short, optical coupling loss can be suppressed. By interposing a refractive index matching adhesive 53 between the optical waveguide 30 and the photoelectric element 20, it is possible to further reduce the optical coupling loss.

In the above description, the FPC is used as an example, but other materials can be used as long as the cavity structure can be formed and the FPC can be bent into a U-shape or a U-shape. A circuit board may also be used. For example, it may be a flexible substrate, a stretchable substrate, a sheet substrate, or the like.

(Third embodiment)
In FIG. 2 of the second embodiment, the number of cores in the optical waveguide is two, but the number of cores is not limited to this, and may be one optical fiber, or three or more. Also good. As an example, FIG. 4 shows an optical waveguide 30a having four cores 31a.

A plan view and a sectional view of an FPC 10a for mounting this optical waveguide 30a are shown in FIGS. 5(a) and 5(b). A slit-shaped first cavity 13a is provided so as to correspond to the outer shape of the optical waveguide 30a, and a second cavity 14a is provided inside the first cavity 13a. A photoelectric element 20a is mounted on the bottom surface of the second cavity 14a at a position corresponding to the core 31a.

FIG. 6 shows an enlarged sectional view of a portion where the optical waveguide 30a is mounted on the FPC 10a. As in the second embodiment, the end surface of the optical waveguide 30a hits the bottom surface of the first cavity 13a, thereby positioning the FPC 10a in the thickness direction and positioning the FPC 10a in the length direction with a predetermined margin. It is The optical waveguide 30 is fixed to the FPC 10a with an adhesive 53a in a state in which the optical axes of the core 31a and the photoelectric element 20a are precisely aligned. Also, as in the second embodiment, the inside of the second cavity 14a is filled with a refractive index matching adhesive 53a. Although not shown in the drawings, by bending and fixing the extended portion of the FPC 10a in the direction along the optical waveguide 30a, a compact optical module in which the optical axes of the optical waveguide 30a and the photoelectric element 20a are accurately aligned. can be obtained. In the above example, the number of cores 31a is four, but the number of cores 31a is not limited to four.

(Fourth embodiment)
In this embodiment, a method for manufacturing an optical module will be described. 7 to 11 are cross-sectional views for explaining the method of manufacturing the optical module. Note that the description uses the optical module 100 of the second embodiment without the reinforcing plate.

First, as shown in FIG. 7, a module in which a photoelectric element 20 is mounted in the second cavity 14 of the FPC 10, and a signal processing IC 40 and an electronic component 41 such as a capacitor are mounted on the surface of the extending portion 15 outside the cavity structure. prepare. Then, it is fixed on the stage 60 . Fixation can be performed, for example, by adsorption. Also, the arm 61 holds the optical waveguide 30 . It is assumed that the signal processing IC 40 and the electronic component 41 are sealed with a mold resin 42 and that the top surface of the mold resin 42 is flat. Further, for example, the photoelectric element 20 can be connected to the wiring 12 using a bump, and the connection portion between the photoelectric element 20 and the signal processing IC 40 can be filled with the underfill resin 20 . At this stage, it is preferable to roughly align the end face of the optical waveguide 30 and the horizontal position of the first cavity 13 .

Next, as shown in FIG. 8, the adhesive is supplied into the first cavity 13 . Here, it is assumed that the refractive index matching adhesive 53 is supplied to both the first cavity 13 and the second cavity 14 . The refractive index matching adhesive 53 is supplied using, for example, a dispenser 62 or the like until the bottom surface of the first cavity 13 is submerged.

Next, as shown in FIG. 9, the arm 61 is moved to insert the end of the optical waveguide 30 into the first cavity 13 and hit the end of the optical waveguide 30 against the bottom surface of the first cavity 13. . Next, before the refractive index matching adhesive 53 is cured, optical axis alignment between the core 31 exposed from the end face of the optical waveguide 30 and the photoelectric element 20 is performed. Alignment can be performed, for example, by recognizing the positions of the tip of the optical waveguide 30 and the photoelectric element 20 using a camera, calculating the necessary amount of movement of the arm, and moving the arm accordingly. Active alignment may also be performed by driving the photoelectric element 20 . For example, if the photoelectric element 20 is a light-emitting element, the photoelectric element 20 can be caused to emit light, and the other end of the optical waveguide 30 can be adjusted to a position where the amount of received light is maximized. Also, if the photoelectric element 20 is a light receiving element, light can be incident from the other end of the optical waveguide 30 and the position can be adjusted to maximize the amount of light received by the photoelectric element. If the module mounted on the FPC 10 alone cannot emit light or receive light, an auxiliary circuit that enables light emission and light reception may be set outside. Next, while maintaining this positional relationship, the refractive index matching adhesive 53 is cured. When the refractive index matching adhesive 53 is a photocurable resin, it can be cured by irradiating light from a spot light source 63, for example, as in the example of FIG. In the case of a thermosetting resin, it may be cured by heating with a heater or the like.

Next, as shown in FIG. 10, an adhesive sheet 51 is pasted on the mold resin 42 positioned above the FPC 10 . For the adhesive sheet 51, for example, an instant adhesive sheet that reacts with moisture in the air or on the surface of the adherend and cures in a short period of time, or a thermosetting or thermoplastic adhesive can be used. Also, in addition to sheet-like ones, gel-like ones can also be applied.

Next, as shown in FIG. 11 , the FPC 10 is bent in a U-shape or U-shape, and the mold resin 42 and the side surface of the optical waveguide 30 are adhered and fixed with an adhesive sheet 51 . FIG. 11 schematically shows how a roller 64 is used to gradually press the FPC 10 against the side surface of the optical waveguide 30 from the vicinity of the cavity structure. FIG. 11 depicts a state in which the extending portion 15 on the left side of the drawing is being adhered, but the processing is performed until the adhesive sheet 51 is adhered to the side surface of the optical waveguide 30 . Then, by the same method, the extending portion 15 on the right side of the drawing is also adhered to the side surface of the optical waveguide 30 to complete an optical module in which the FPC 10 is bent in a U-shape or U-shape.

As a method of arranging the rollers between the stage 60 and the rear surface of the FPC 10, it is possible to adopt a method of arranging the rollers in a state where the surface of the end portion of the FPC 10 is sucked and lifted. Alternatively, a method of blowing air against the FPC 10 through a hole provided in the stage 60 to float a part of the FPC 10 and disposing the roller may be used. Alternatively, when an instant adhesive type is applied to the adhesive sheet 51, after the adhesive sheet 51 is supplied onto the mold resin 42 on one of the extending portions 15 and fixed by adhesion to the side surface of the optical waveguide 30, the other is similarly adhesively fixed. preferably. When a thermosetting or thermoplastic adhesive sheet 51 is applied, after the adhesive sheet 51 is supplied on both mold resins 42, the FPC 10 is bent in a U-shape or U-shape to bond both surfaces at the same time. May be fixed.

Although the above description was given using the configuration without the reinforcing plate 50, the same can be applied to the case where the reinforcing plate 50 is provided. In this case, the member to which the mold resin 42 on the extended portion 15 is adhered is the reinforcing plate 50 .

(Fifth embodiment)
In the first to fourth embodiments, the first cavity and the second cavity are recesses recessed from the surface of the FPC, but they may be formed on the FPC. FIG. 12 is a sectional view showing a configuration in which the first cavity 13b is formed by the reinforcing plate 50b and the surface of the FPC 10b, and the second cavity 14b recessed from the surface of the FPC 10b is provided inside the first cavity 13b. is.

When the optical waveguide 30 is mounted in this configuration, as shown in FIG. 13, the optical waveguide 30 is inserted into the first cavity 13b, and the end surface of the optical waveguide 30 is placed on the surface of the FPC 10b that contacts the bottom surface of the first cavity 13b. bump into. Then, the adhesive 52 is filled between the reinforcing plate 50b and the optical waveguide 30 and hardened to fix the optical waveguide 30 . Aligning the optical axes of the optical waveguide 30 and the photoelectric element 20, filling the second cavity 14b with the refractive index matching adhesive 53, and the like before the adhesive sheet 2 is cured are the second to second methods. 4 embodiment. Also, the adhesive 52 may be the same as the refractive index matching adhesive 53 .

It is also possible to form the first cavity and the second cavity with the reinforcing plate and the surface of the FPC without digging into the FPC. FIG. 14 is a cross-sectional view showing this configuration. The reinforcing plate 50c having this structure has a step portion 50c' inside. The top surface of the step portion 50c' becomes the bottom surface of the first cavity 13c. A region surrounded by the lower side of the stepped portion 13c and the surface of the FPC 10c becomes the second cavity 14c.

When mounting the optical waveguide 30 in this configuration, as shown in FIG. 15, the optical waveguide 30 is inserted into the first cavity 13c, and the end surface of the optical waveguide 30 is placed at the stepped portion 50c that contacts the bottom surface of the first cavity 13c. ´. Then, the adhesive 52 is filled between the reinforcing plate 50c and the optical waveguide 30 and hardened to fix the optical waveguide 30 therein. Aligning the optical axes of the optical waveguide 30 and the photoelectric element 20, filling the second cavity 14b with the refractive index matching adhesive 53, and the like before the adhesive sheet 2 is cured are the second to second methods. 4 embodiment. Also, the adhesive 52 may be the same as the refractive index matching adhesive 53 .

(Sixth embodiment)
FIG. 16 is a diagram showing the outline of the configuration of the optical module of the sixth embodiment. In the first to fifth embodiments, the thickness of the FPC is constant, but in the optical module 200 of this embodiment, the bent portion of the FPC 10d is thinner than the other portions. Specifically, the thickness can be reduced by reducing the number of layers in the area where the FPC 10d is bent, compared to other areas. With such a structure, the radius of curvature of the bent portion of the FPC 10d can be reduced. Therefore, the swelling at the bent portion of the FPC 10d can be reduced, and further miniaturization is possible. In addition, since the flexibility of the bent portion is increased, the bending process is facilitated.

Some or all of the above embodiments may be described as the following additional remarks, but are not limited to the following.
(Appendix 1)
having a printed circuit board, an optoelectronic device, and an optical waveguide;
The printed circuit board is
a first recess;
a second recess recessed in a portion of the bottom of the first recess;
an extending portion extending along the longitudinal direction of the optical waveguide via a bent portion outside the first recess;
the photoelectric element is positioned in the second recess such that its light input/output surface faces the bottom of the first recess;
An optical module, wherein one end of the optical waveguide contacts a portion of the bottom of the first recess other than the part.
(Appendix 2)
The optical module according to appendix 1, wherein the printed circuit board is bent in a U shape or a U shape.
(Appendix 3)
3. The optical module according to appendix 1 or 2, wherein the side surface of the optical waveguide and the side surface of the first recess are fixed with an adhesive.
(Appendix 4)
4. The optical module according to any one of appendices 1 to 3, wherein the upper surface of the extended portion mounted on the optical waveguide side and the side surface of the optical waveguide are adhered to each other.
(Appendix 5)
5. The optical module according to appendix 4, wherein the upper surface of the optical module mounted on the extending portion is molded resin.
(Appendix 6)
6. The optical module according to appendix 4 or 5, wherein the upper surface of the one mounted on the extending portion is flat.
(Appendix 7)
7. The optical module according to any one of appendices 1 to 6, wherein the first recess is recessed in the surface of the printed circuit board.
(Appendix 8)
8. The optical module according to any one of Appendices 1 to 7, wherein the optical waveguide has a reinforcing plate on its side surface.
(Appendix 9)
The optical module according to appendix 8, wherein the first recess is an area surrounded by the side surface of the reinforcing plate and the surface of the printed circuit board.
(Appendix 10)
The reinforcing plate has a step portion inside,
The optical module according to appendix 8, wherein the portion other than the part of the bottom of the first recess includes the upper surface of the stepped portion.
(Appendix 11)
11. The optical module according to any one of appendices 1 to 10, wherein the bent portion of the printed circuit board is thinner than other portions.
(Appendix 12)
12. The optical module according to any one of appendices 1 to 11, wherein the first recess is slit-shaped.
(Appendix 13)
13. The optical module according to claim 12, wherein the second cavity is slit-shaped.
(Appendix 14)
14. The optical module according to any one of appendices 1 to 13, wherein the optical waveguide has a plurality of cores.
(Appendix 15)
15. The optical module according to any one of appendices 1 to 14, wherein the printed circuit board is a flexible printed circuit board.
(Appendix 16)
providing a first recess on the printed circuit board;
forming a second recess in a part of the bottom of the first recess;
bringing one end of the optical waveguide into contact with a portion of the bottom of the first recess other than the part;
forming an extension portion of the printed circuit board extending along the longitudinal direction of the optical waveguide via a bent portion outside the first recess;
A method of manufacturing an optical module, comprising: disposing a photoelectric element in the second recess so that a light incident/exiting surface of the photoelectric element faces the bottom of the first recess.
(Appendix 17)
16. The method of manufacturing an optical module according to appendix 15, wherein the printed circuit board is bent into a U shape or a U shape.

The present invention has been described above using the above-described embodiments as exemplary examples. However, the invention is not limited to the above embodiments. That is, within the scope of the present invention, various aspects that can be understood by those skilled in the art can be applied to the present invention.

1 printed circuit board 2, 20 photoelectric element 3, 30 optical waveguide 10 FPC
REFERENCE SIGNS LIST 11 substrate 12 wiring 13 first cavity 14 second cavity 15 extension 16 electrode 20 photoelectric element 31 core 32 clad 40 signal processing IC
41 electronic component 42 mold resin 50 reinforcing plate 51 adhesive sheet 52 adhesive 53 refractive index matching adhesive 60 stage 61 arm 62 dispenser 63 spot light source 64 roller 100, 200 optical module

Claims (10)

having a printed circuit board, an optoelectronic device, and an optical waveguide;
The printed circuit board is
a first recess recessed in the surface of the printed circuit board ;
a second recess recessed in a portion of the bottom of the first recess;
an extending portion extending along the longitudinal direction of the optical waveguide via a bent portion outside the first recess;
the photoelectric element is positioned in the second recess such that its light input/output surface faces the bottom of the first recess;
An optical module, wherein one end of the optical waveguide abuts on a portion of the bottom of the first recess other than the part. 2. The optical module according to claim 1, wherein the printed circuit board is bent in a U shape or a U shape. 3. The optical module according to claim 1, wherein a side surface of said optical waveguide and a side surface of said first recess are fixed with an adhesive. 4. The optical module according to any one of claims 1 to 3, wherein the upper surface of the extending portion mounted on the optical waveguide side is adhered to the side surface of the optical waveguide. 5. The optical module according to any one of claims 1 to 4, wherein the first recess is recessed in the surface of the printed circuit board. The optical module according to any one of claims 1 to 5, wherein the optical waveguide has a reinforcing plate on its side surface. 7. The optical module according to claim 6, wherein the first recess is an area surrounded by the side surface of the reinforcing plate and the surface of the printed circuit board. 8. The optical module according to any one of claims 1 to 7, wherein the bent portion of the printed circuit board is thinner than other portions. The optical module according to any one of claims 1 to 8, wherein the printed circuit board is a flexible printed circuit board. recessing a first recess in the surface of the printed circuit board ;
forming a second recess in a part of the bottom of the first recess;
bringing one end of the optical waveguide into contact with a portion other than the part of the bottom of the first recess;
forming an extension portion of the printed circuit board extending along the longitudinal direction of the optical waveguide via a bent portion outside the first recess;
A method of manufacturing an optical module, wherein a photoelectric element is arranged in the second recess such that a light incident/emission surface of the photoelectric element faces the bottom of the first recess.

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