JP2011107327A - Optical module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical module with which optical axis alignment between an optical element and an optical fiber can be performed easily and accurately. <P>SOLUTION: The optical module 1 includes a transmission module body 2 and a receptacle 5 for accepting an optical connector plug 4. The transmission module body 2 includes: a lead frame 9; a plurality of electronic components 10 including a light-emitting element 10a to be mounted on the lead frame 9; and a mold body 11 for which the respective electronic components 10 are sealed with a resin. Near the light-emitting element 10a in the lead frame 9, there is formed a positioning hole 15 which becomes a reference for positioning when the light-emitting element 10a is mounted and when the mold body 11 is formed. In a region where no mold body 11 is formed in the lead frame 9, a positioning auxiliary hole 16 is formed. In the mold body 11, a through-hole 18 is formed that exposes the positioning hole 15 of the lead frame 9. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an optical module used in optical communication or the like.

  As a conventional optical module, for example, as described in Patent Document 1, a module main body formed by molding an optical element mounted on a lead frame, a case covering a mold portion of the module main body, There has been known one provided with a sleeve having an optical fiber inserted into a cylindrical portion.

JP 2001-168380 A

  However, in the above prior art, an error in positioning accuracy of the optical element with respect to the lead frame, an error in positioning accuracy of the mold part with respect to the lead frame, and an error in positioning accuracy of the sleeve with respect to the mold part are superimposed and accumulated. The optical axis may deviate from the optical element.

  The objective of this invention is providing the optical module which can perform the optical axis alignment of an optical element and an optical fiber simply and with high precision.

  An optical module of the present invention includes a module main body having a molded body formed by resin-sealing an optical element mounted on a lead frame, an optical connector plug having an optical fiber optically coupled to the optical element, and an optical connector plug. The lead frame is provided with a positioning hole serving as a reference for alignment when the optical element is mounted on the lead frame and when the mold body is formed. The mold body includes a receptacle. A through hole that engages with the portion and exposes the positioning hole is provided.

  When manufacturing such an optical module of the present invention, the mounting position of the optical element with respect to the lead frame is determined with reference to the positioning hole of the lead frame, and the optical element is mounted at the mounting position. Next, the set position of the mold for the lead frame is determined with reference to the positioning hole of the lead frame, and in this state, the optical element is resin-sealed to form a mold body having a through hole exposing the positioning hole. . Next, for example, the positioning protrusion provided on the receptacle is inserted into the positioning hole of the lead frame through the through hole of the mold body, thereby aligning the receptacle with the mold body with reference to the positioning hole. Secure to. As described above, the positions of the optical element, the mold body, and the receptacle are all determined based on the positioning hole of the lead frame. For this reason, the positioning accuracy of the receptacle part with respect to the optical element is improved. At this time, an optical connector plug having an optical fiber optically coupled to the optical element is received in the receptacle portion. Thereby, the optical axis alignment of the optical fiber with respect to the optical element can be performed easily and with high accuracy.

  Preferably, the receptacle part has a positioning projection inserted into the positioning hole through the through hole. In this case, the positioning projection of the receptacle part is inserted into the positioning hole of the lead frame through the through hole of the mold body, whereby the position of the receptacle part with respect to the lead frame is determined based on the positioning hole.

  At this time, the receptacle portion has a plurality of positioning protrusions, and a positioning auxiliary hole into which at least one of the plurality of positioning protrusions is inserted is provided in a region of the lead frame where the mold body is not formed. It is preferable. In this case, the positioning protrusion of the receptacle part is inserted into the positioning hole and the positioning auxiliary hole of the lead frame, respectively, so that the positional deviation in the rotational direction of the receptacle part with respect to the lead frame is suppressed. Therefore, the positioning accuracy of the receptacle part with respect to the optical element can be further improved.

  ADVANTAGE OF THE INVENTION According to this invention, the optical axis alignment with an optical element and an optical fiber can be performed simply and with high precision. As a result, the optical element and the optical fiber can be optically coupled with high efficiency.

It is a perspective view which shows one Embodiment of the optical module concerning this invention. It is a disassembled perspective view of the optical module shown in FIG. It is sectional drawing of the optical module shown in FIG. FIG. 3 is a perspective view illustrating a state in which a transmission module main body and a reception module main body illustrated in FIG. 2 are arranged side by side. FIG. 3 is a front view showing a state where the transmission module main body and the reception module main body shown in FIG. 2 are arranged side by side. FIG. 4 is an exploded cross-sectional view of a main part of the optical module shown in FIG. 3. It is a schematic sectional drawing which shows an example of the conventional general optical module.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of an optical module according to the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a perspective view showing an embodiment of an optical module according to the present invention. 2 is an exploded perspective view of the optical module shown in FIG. 1, and FIG. 3 is a cross-sectional view of the optical module shown in FIG. In each figure, the optical module 1 of this embodiment includes a transmission module main body 2, a reception module main body 3, an optical connector plug 4, a receptacle 5, a header 6, a circuit board 7, and a cover 8. Yes. Note that the receptacle 5 and the header 6 may be integrally formed.

  As shown in FIGS. 4 and 5, the transmission module main body 2 includes a lead frame 9, a plurality of electronic components 10 including a light emitting element (laser diode: LD) 10a mounted on the lead frame 9, and these electronic components. And a molded body 11 formed by sealing the component 10 with a transparent resin. As the transparent resin, cycloolefin polymer, PMMA, polycarbonate or the like is used.

  The lead frame 9 has a plurality of lead terminals 12, a non-component mounting area 13, and a component mounting area 14 provided between each lead terminal 12 and the non-component mounting area 13.

  In the vicinity of the light emitting element 10a in the component mounting area 14, a positioning hole 15 serving as a reference for alignment when the light emitting element 10a is mounted at a predetermined position and when the mold body 11 is formed is formed. Further, in the non-component mounting region 13, a positioning auxiliary hole 16 is formed along with a positioning hole 15 which serves as a reference for alignment when the receptacle 5 is connected to the mold body 11. The positioning hole 15 is disposed between the light emitting element 10 a and the positioning auxiliary hole 16. Further, it is desirable that the positioning auxiliary hole 16 be arranged as far as possible from the light emitting element 10a.

  The mold body 11 is formed so as to seal the component mounting region 14 of the lead frame 9. A lens portion 17 for condensing light emitted from the light emitting element 10a is formed in a spherical convex shape at a position facing the light emitting element 10a on the front surface of the mold body 11 (the surface on the mounting side of the electronic component 10). Yes.

  As shown in FIG. 6, the mold body 11 is formed with a through hole 18 that exposes the positioning hole 15 of the lead frame 9 as a whole. That is, the through hole 18 communicates with the positioning hole 15. Further, an auxiliary hole 19 for connecting the receptacle 5 to the mold body 11 is formed at the end of the front surface of the mold body 11 on the lead terminal 12 side.

  The receiving module body 3 includes a lead frame 20, a plurality of electronic components 21 including a light receiving element (photodiode: PD) 21 a mounted on the lead frame 20, and these electronic components 21 are sealed with a transparent resin. And a mold body 22. The material of the transparent resin is the same as the transparent resin that forms the mold body 11 described above.

  The lead frame 20 includes a plurality of lead terminals 23, a non-component mounting area 24, and a component mounting area 25 disposed between each lead terminal 23 and the non-component mounting area 24.

  In the vicinity of the light receiving element 21a in the component mounting area 25, a positioning hole 26 serving as a reference for alignment when the light receiving element 21a is mounted at a predetermined position and when the mold body 22 is formed is formed. Further, in the non-component mounting region 24, a positioning auxiliary hole 27 is formed along with the positioning hole 26, which serves as a reference for alignment when the receptacle 5 is connected to the mold body 22. The positioning hole 26 is disposed between the light receiving element 21 a and the positioning auxiliary hole 27. Further, it is desirable that the positioning auxiliary hole 27 is arranged as far as possible from the light receiving element 21a.

  The mold body 22 is formed so as to seal the component mounting region 25 of the lead frame 20. A lens portion 28 for condensing light incident on the light receiving element 21a is formed in a spherical convex shape at a position facing the light receiving element 21a on the front surface of the mold body 22 (the surface on the mounting side of the electronic component 21). ing.

  A through hole 29 is formed in the mold body 22 to expose the positioning hole 26 of the lead frame 20 as a whole. That is, the through hole 29 communicates with the positioning hole 26. Further, an auxiliary hole 30 for connecting the receptacle 5 to the mold body 22 is formed at the end of the front surface of the mold body 22 on the lead terminal 23 side.

  In the state where the transmission module main body 2 and the reception module main body 3 are arranged side by side, the shape of the mold body 11 (the positions of the through hole 18, the lens portion 17 and the auxiliary hole 19) and the shape of the mold body 22 (the through hole 29). The positions of the lens portion 28 and the auxiliary hole 30) are symmetrical.

  Returning to FIGS. 1 to 3, the optical connector plug 4 has a connector body 31. A ferrule portion 33 that holds an optical fiber 32 that is optically coupled to the light emitting element 10a and the light receiving element 21a is provided at the front portion of the connector body 31.

  The connector body 31 is accommodated and held in the header 6. The receptacle 5 is fixed to the front end portion of the header 6 with an adhesive. The receptacle 5 is provided with sleeves 34 for receiving the ferrule portions 33 of the optical connector plug 4.

  On the front side of the receptacle 5, the transmission module main body 2 and the reception module main body 3 are arranged side by side. Four positioning projections 35 for aligning the receptacle 5 with the lead frames 9 and 20 are provided on the front end surface of the receptacle 5. These positioning projections 35 are fitted into the positioning holes 15 and auxiliary positioning holes 16 of the lead frame 9 and the positioning holes 26 and auxiliary positioning holes 27 of the lead frame 20. Note that the front end surface of the receptacle 5 may also be provided with a protrusion that fits into the auxiliary hole 19 of the mold body 11 and the auxiliary hole 30 of the mold body 22.

  Each lead terminal 12 of the transmission module body 2 and each lead terminal 23 of the reception module body 3 are mounted on the circuit board 7. A header 6 is attached to the circuit board 7. The transmission module main body 2 and the reception module main body 3 are covered with a cover 8 made of, for example, SUS sheet metal.

  In the assembly process of the optical module 1 configured as described above, when the light emitting element 10a is mounted on the lead frame 9, the mounting position of the light emitting element 10a is determined based on the positioning hole 15 provided in the lead frame 9, and the light receiving element 10a is received. When the element 21 a is mounted on the lead frame 20, the mounting position of the light receiving element 21 a is determined with reference to the positioning hole 26 provided in the lead frame 20. At this time, by providing the positioning holes 15 and 26 near the mounting positions of the light emitting element 10a and the light receiving element 21a, it is possible to contribute to an improvement in positioning accuracy of the light emitting element 10a and the light receiving element 21a.

  When the mold body 11 is formed in the component mounting area 14 of the lead frame 9, the setting position of the molding die is determined based on the positioning hole 15 in the same manner as described above, and the mold body 22 is placed in the component mounting area 25 of the lead frame 20. When forming the molding die, the setting position of the mold for molding is determined based on the positioning hole 26 as described above. Accordingly, the position of the lens portion 17 of the mold body 11 is determined with reference to the positioning hole 15, and the position of the lens portion 28 of the mold body 22 is determined with reference to the positioning hole 26.

  When the receptacle 5 is fixed to the transmission module body 2 and the reception module body 3, the positioning frames 35 of the receptacle 5 are positioned through the through holes 18 and 29 of the mold bodies 11 and 22, respectively. The receptacle 5 is inserted into the transmission module main body 2 and the reception module main body 3 by inserting into the holes 15 and 26 and inserting the other two positioning projections 35 of the receptacle 5 into the positioning auxiliary holes 16 and 27 of the lead frames 9 and 20, respectively. Positioning is performed (see FIG. 3). At this time, the lens portion 17 of the transmission module main body 2 and the lens portion 28 of the reception module main body 3 are inserted into the respective sleeves 34 of the receptacle 5 and face the respective ferrule portions 33 (see FIG. 3).

  As described above, the positioning projection 35 is inserted into the positioning hole 15 and the positioning auxiliary hole 16 of the transmission module main body 2, and the positioning projection 35 is inserted into the positioning hole 26 and the positioning auxiliary hole 27 of the reception module main body 3. The rotational displacement of the receptacle 5 with respect to the module main body 2 and the receiving module main body 3 is suppressed. At this time, since it is not necessary to make the accuracy of the positioning auxiliary holes 16, 27 higher than the accuracy of the positioning holes 15, 26, the diameter of the positioning auxiliary holes 16, 27 is larger than the diameter of the positioning holes 15, 26. However, as the positioning auxiliary holes 16 and 27 are arranged farther from the light emitting element 10a and the light receiving element 21a, the influence of the positional deviation of the receptacle 5 due to the gap between the positioning auxiliary holes 16 and 27 and the positioning projection 35 can be reduced. it can.

  Here, as a comparative example, an example of a conventional general optical module is shown in FIG. The optical module 50 shown in FIG. 1 includes an optical connector plug 56 having a module main body 51, a receptacle 52 fixed to the module main body 51, and a ferrule portion 55 that is received by a sleeve 53 of the receptacle 52 and holds an optical fiber 54. And.

  The module body 51 includes a lead frame 58 on which a plurality of electronic components (not shown) including an optical element (light emitting element or light receiving element) 57 are mounted, and a mold body 59 formed by sealing the plurality of electronic components with a transparent resin. And have. The lead frame 58 is formed with a positioning hole 60 that serves as a reference for positioning when the optical element 57 is mounted and when the mold body 59 is formed. The mold body 59 is provided with a lens portion 61.

  In such an assembly process of the optical module 50, the optical element 57 is mounted at a predetermined position of the lead frame 58 with reference to the positioning hole 60 of the lead frame 58, and a molding die is set with the positioning hole 60 as a reference. Then, the mold body 59 is formed. Thereafter, the receptacle 52 (sleeve 53) is positioned with respect to the mold body 59 on the basis of the shape of the mold body 59 (here, the lens portion 61), and the receptacle 52 is fixed to the mold body 59.

  However, in this case, the shape error of the mold body 59 (position error of the lens portion 61) affects the positioning accuracy of the sleeve 53, and consequently affects the positioning accuracy of the ferrule portion 55 received by the sleeve 53. . As a result, it becomes difficult to sufficiently suppress the optical axis shift between the optical element 57 and the optical fiber 54.

  On the other hand, in the present embodiment, a through hole 18 for exposing the positioning hole 15 of the lead frame 9 is formed in the mold body 11 of the transmission module body 2, and the positioning hole 26 of the lead frame 20 is formed in the mold body 22 of the reception module body 3. By forming the through hole 29 that exposes the positioning hole 35, the positioning projection 35 of the receptacle 5 is inserted into the positioning holes 15 and 26, and the relative position of the receptacle 5 with respect to the mold bodies 11 and 22 is determined. That is, not only the mounting position of the light emitting element 10a and the light receiving element 21a, the setting position of the mold for forming the mold bodies 11 and 22, but also the relative position of the receptacle 5 with respect to the mold bodies 11 and 22 are determined by the positioning holes 15. , 26 as a reference. Accordingly, the influence of the shape error of the mold bodies 11 and 22 on the positioning accuracy of the receptacle 5 is eliminated, and as a result, the influence of the shape error of the mold bodies 11 and 22 on the positioning accuracy of the ferrule portion 33 is eliminated. It becomes like this.

  Thereby, the alignment of the optical fiber 32 with respect to the light emitting element 10a and the light receiving element 21a can be accurately and easily performed, and the optical axis deviation between the light emitting element 10a and the light receiving element 21a and the optical fiber 32 can be sufficiently suppressed. it can. As a result, the light emitting element 10a and the light receiving element 21a and the optical fiber 32 can be optically coupled with high efficiency.

  The present invention is not limited to the above embodiment. For example, in the above embodiment, the receptacle 5 manufactured in advance is fixed to the mold body 11 of the transmission module body 2 and the mold body 22 of the reception module body 3. After forming 22, the receptacle molding die may be set by using the positioning holes 15 and 26 of the lead frames 9 and 20 as a reference, and the receptacle may be molded. In this case, the receptacle is further double-molded on the mold bodies 11 and 22.

  Moreover, although the optical module 1 of the said embodiment is an optical transmission / reception module provided with the transmission module main body 2 and the reception module main body 3, this invention was provided with either one of the transmission module main body 2 or the reception module main body 3. The present invention can also be applied to an optical transmission module and an optical reception module.

DESCRIPTION OF SYMBOLS 1 ... Optical module, 2 ... Transmission module main body, 3 ... Reception module main body, 4 ... Optical connector plug, 5 ... Receptacle (receptacle part), 6 ... Header (receptacle part), 9 ... Lead frame, 10a ... Light emitting element (light) Element), 11 ... molded body, 15 ... positioning hole, 16 ... positioning auxiliary hole, 18 ... through hole, 20 ... lead frame, 21a ... light receiving element (optical element), 22 ... molded body, 26 ... positioning hole, 27 ... Positioning auxiliary hole, 29... Through-hole, 32 .. optical fiber, 35.

Claims (3)

A module body having a molded body formed by resin-sealing an optical element mounted on a lead frame;
An optical connector plug having an optical fiber optically coupled to the optical element;
A receptacle for receiving the optical connector plug;
The lead frame is provided with a positioning hole that serves as a reference for alignment when the optical element is mounted on the lead frame and when the mold body is formed.
An optical module, wherein the mold body is provided with a through hole that engages with the receptacle portion and exposes the positioning hole.   The optical module according to claim 1, wherein the receptacle portion has a positioning protrusion to be inserted into the positioning hole through the through hole. The receptacle part has a plurality of positioning protrusions,
The optical module according to claim 2, wherein a positioning auxiliary hole into which at least one of the plurality of positioning protrusions is inserted is provided in a region of the lead frame where the mold body is not formed. .

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