JPH08262281A - Substrate structure of optical module - Google Patents

Abstract

PURPOSE: To attain a substrate structure of an optical module of a large packaging area of electronic parts with a small number of parts and good assembly workability at the time of making remedy for noise by an electric field. CONSTITUTION: This substrate structure of the optical module is the substrate structure of the optical module for packaging optical operating elements and electronic parts 62, 65 for driving these optical operating elements. The inside surfaces 58a of bent substrate bodies 58, 59 for packaging the electronic parts 62, 65 are provided with packaging surfaces and the outside surfaces 58b of the substrate bodies 58, 59 are provided with conductive shielding parts 63, 66, by which the remedy for the electric field noise is efficiently attained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate structure of an optical module used in an optical communication system such as an optical data link or an optical local area network (LAN) which uses light as an information transmission medium.

[0002]

2. Description of the Related Art As an example of a conventional optical module, there is JP-A-2-271308. The optical module disclosed in this publication includes a cylindrical sleeve 100 as shown in FIG. This sleeve 10
0 is made of metal such as stainless steel, and the light actuating element 102 is accommodated at one end side thereof, and the other end side thereof is
A ferrule insertion hole 101a for inserting a ferrule provided at the tip of a connector plug (not shown) is formed. Further, the sleeve 100 is provided with the light actuating element 10
2 is fixed with an adhesive or the like. Furthermore, the sleeve 100
A flange 101b is formed on the flange 101b.
b is fixed to an upright piece 104a rising from a ceramic package body 104 with an adhesive or the like.
The circuit board 103 is supported by the package body 104, and the terminals of the light actuating element 102 are connected to electronic components 105 such as bare chip ICs mounted on the circuit board 103 by wire bonding (not shown).

The package body 104 also includes an inner lead pin 106 provided upright on the inner side thereof and an outer lead pin 107 provided upright on the outer side and electrically connected to the inner lead pin 106. The inner lead pin 106 is electrically connected to each terminal on the circuit board 103 by wire bonding, and a wiring pattern (not shown) and the electronic component 105 are sealed by a lid 108.

[0004]

However, in the case where the conventional optical module is entirely formed of resin, in order to shield electric field noise from the outside, a grounded metal net member is used on the circuit board 103. Since it is necessary to cover the wiring pattern and the electronic component 105, the number of components of the optical module is increased and the assembling workability is deteriorated.

The present invention has been made in order to solve the above problems. In order to take measures against noise caused by an electric field, the number of parts is small and the assembling workability is good, and the mounting area of electronic parts is large. The aim is to achieve a substrate structure for the module.

[0006]

A substrate structure for an optical module according to the present invention is a substrate structure for an optical module on which an optical actuation element and an electronic component for driving the optical actuation element are mounted. Also, the mounting surface is provided on the inner surface of the substrate body, and the conductive shield portion is provided on the outer surface of the substrate body.

More specifically, the substrate body is integrally formed of a top plate portion, a bottom plate portion and a connecting portion, and one end of the top plate portion and one end of the bottom plate portion are connected via the connecting portion to form a top plate. The other end of the section and the other end of the bottom plate section are fixed via conductive columns.

More specifically, the substrate body is integrally formed of the first and second top plate portions, the bottom plate portion, and the first and second connecting portions, and the first and second end portions are provided at both ends of the bottom plate portion. And a tip of the first top plate extending from the first connection and a tip of the second top extending from the second connection are mounted on the mounting surface of the bottom plate. It is a structure fixed to the upper surface of the pillar provided.

More specifically, the shield part has a mesh structure.

More specifically, the board body is made of a flexible printed board.

[0011]

In the substrate structure of the optical module according to the present invention, when an electronic component is mounted on the mounting surface formed on the inner surface of the bent substrate body, electric field noise generated from the electronic component of the substrate body is reduced. After being caught by the shield part formed on the outer surface of, it can be released to the outside through the ground. Further, since the electronic parts are surrounded by the shield part, the electric field noise invading from the outside can be caught by the shield part before reaching the electronic parts.
The electronic components mounted on the mounting surface of the board body are not adversely affected.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the substrate structure of an optical module according to the present invention will be described in detail below with reference to the drawings.

In FIG. 1 and FIG. 2, reference numeral 1 denotes a transceiver type optical module, and this optical module 1 includes an optical actuating element for reception (for example, a light receiving diode) 2 and an optical actuating element for transmission. (Eg semiconductor laser) 3
And are assembled together. This optical module 1
Has a housing 4 made of PPS (polyphenylene sulfide) resin and having a U-shaped cross section. Also,
Inside the housing 4, resin sleeves 5 and 6 for accommodating the light actuating elements 2 and 3, a resin sleeve holder 7 for holding the respective sleeves 5 and 6, and the light actuating element 2 are provided. , 3 which are electrically connected to a plurality of terminals 2a and 3a protruding from the circuit board 3, and a circuit board 8 having a flexible printed board fixed to the surface thereof.

Here, the sleeves 5 and 6 accommodate a cylindrical ferrule (not shown) which is provided at the tip of a connector plug (not shown) connected to the optical module 1 and constitutes the tip of an optical fiber. For holding the cylindrical ferrule holding portion 10, a cylindrical element holding portion 11 for accommodating the cylindrical light actuating element 2, and a boundary region between the ferrule holding portion 10 and the element holding portion 11 are perpendicular to the axis. And a flange 12 formed on the outer surface of the sleeve 5 so as to extend in the direction. Further, the ferrule holding portion 10 is formed with an elongated ferrule insertion hole 10a having a diameter substantially equal to that of the ferrule 9a, and the element holding portion 11 is substantially equal to or slightly larger than the outer shape of the light actuating element 2. A large diameter element insertion hole 11a is formed. In addition,
Reference numeral 50 is a member for blindly covering the pair of latch levers 22 and 23 seen through the bottom opening of the housing 4.

As shown in FIGS. 2 and 3, the circuit board 8
Is provided with a rectangular base body 45 having a predetermined thickness and an appropriate bending strength, and a pair of board bodies 58 made of a flexible printed board which has an extremely high degree of bending flexibility and is easy to process on the surface of the base body 45. , 59 are fixed.
A circuit for operating the light actuating element 2 is printed on the substrate body 58, and a circuit for operating the light actuating element 3 is printed on the substrate body 59. The substrate body 58 includes a head portion 60a for electrically connecting to the terminal 2a of the light actuating element 2, and a neck portion extending from the front end of the substrate body 58 for electrically connecting the substrate body 58 and the head portion 60a. And 60b. In addition, the substrate body 5
Reference numeral 9 denotes a head portion 61a for electrically connecting to the terminal 3a of the light actuating element 3, and a neck portion 61b extending from one end of the substrate body 59 for electrically connecting the substrate body 59 and the head portion 61a. I have it. And each board body 5
The reference numerals 8 and 59 are fixed on a single substrate 45.

Auxiliary plates 47 and 48 having a predetermined thickness and an appropriate bending strength are fixed to the back surfaces of the head portions 60a and 61a. Also, the neck 60
The members b and 61b are not provided with members for supporting them, and thus have a high degree of freedom in bending. Therefore, the head portions 60a and 61a can be easily raised with respect to the board bodies 58 and 59, and the positional relationship between the circuit board 8 and the light actuating elements 2 and 3 can be freely set.

Now, the substrate body 58 for operating the light actuating element 2 will be described.

The board main body 58 is bent into a U-shape to be composed of a top plate portion 58A, a bottom plate portion 58B and a connecting portion 58C. The connecting portion 58C is connected to one end of the top plate portion 58A and the bottom plate portion. It is connected to one end of 58B. Further, the connecting portion 58C extends in the width direction of the substrate body 58 and stands up between the top plate portion 58A and the bottom plate portion 58B. Therefore, a U-shaped mounting surface for mounting the electronic component 62 is formed on the inner surface 58a of the substrate body 58, and the top plate portion 58A is formed.
A gap having a height H corresponding to the width of the connecting portion 58C is formed between the bottom plate portion 58B and the bottom plate portion 58B. As a result, the electronic component 62 mounted on the mounting surface 58a of the top plate portion 58A.
With this, it is possible to avoid contact with the electronic component 62 mounted on the mounting surface 58a of the bottom plate portion 58B. Further, a conductive shield portion 63 is fixed over the entire outer surface 58b of the substrate body 58. This shield 63 is
Although it can be formed of a metal film, a high electric field noise countermeasure can be achieved by forming a mesh.

Further, the other end of the top plate portion 58A and the bottom plate portion 58B.
Is fixed to the other end via a conductive support 64.
The support column 64 is made of a metal having a quadrangular prism shape, and extends in the width direction of the substrate body 58 so as to face the connecting portion 58C. By electrically connecting the support column 64 to the shield part 63, the four sides of the electronic component 62 can be completely surrounded by the shield part 63 and the support column 64. It is also possible to ground the support column 64 and the shield part 63, respectively, without electrically connecting the support column 64 and the shield part 63.

Next, the substrate main body 59 for operating the light actuating element 3 will be described. However, since the substrate body 59 has substantially the same configuration as the substrate body 58 described above, only a brief description will be given.

The board main body 59 is bent in a U-shape to be composed of a top plate portion 59A, a bottom plate portion 59B, and a connecting portion 59C. The connecting portion 59C is connected to one end of the top plate portion 59A and the bottom plate portion. It is connected to one end of 59B. Therefore, a U-shaped mounting surface for mounting the electronic component 65 is formed on the inner surface 59 a of the substrate body 59. In addition, the substrate body 59
A mesh-like shield portion 66 having conductivity is fixed over the entire outer surface 59b. Further, the other end of the top plate portion 59A and the other end of the bottom plate portion 59B are fixed via a conductive support 67. The pillar 67 is made of a metal having a quadrangular prism shape and extends in the width direction of the substrate body 59.

Here, a pair of substrate bodies 5 are provided on the base 45.
When arranging 8, 59, the support column 64 of the substrate body 58 and the support column 67 of the substrate body 59 face each other, and
4, 67 are closely attached to each other or are separated by a predetermined distance. After that, as shown in FIG. 4, a plurality of lead pins 43 are provided at the rear end of the circuit board 8 (position facing the head portion).
Are fixed at equal intervals. A U-shaped holding portion 43a having a predetermined holding force is formed at one end of each lead pin 43. In addition, a linear lead pin body 43 is provided on the remaining portion.
b is formed. Therefore, by sandwiching each sandwiching portion 43a at the rear end of the circuit board 8, the lead pin 43 can be reliably attached to the circuit board 8 by a touch.

Further, a predetermined one of the plurality of lead pins 43 is used as the ground lead pin 43A, and the ground lead pin 43A and the shield portions 63 and 6 are used.
6 is electrically connected to the ground lead pin 43A.
And the columns 64 and 67 are electrically connected. as a result,
Electric field noise propagating in the housing 4 is shielded by the shield part 6.
It can be reliably captured by 3, 66 and the columns 64, 67.

Next, the procedure for assembling the substrate body 58 will be described.

As shown in FIG. 5, a net-like shield portion 63 is applied to the back surface of a rectangular board body 58 made of a flexible printed board, an electronic component 62 is mounted on the mounting surface 58a, and a support is provided at one end of the board body 58. Fix 64. After that, the board body 58 is bent through two parallel bending lines 68a and 68b which are provided at the center of the board body 58 and extend in the width direction. By fixing the other end of the substrate main body 58 to the upper surface of the support column 64, the integrated top plate portion 58A, bottom plate portion 58B, and connecting portion 58C can be easily created. The board main body 59 is also assembled by the same work as described above, and thus the description thereof is omitted.

Next, a second embodiment of the substrate structure of the optical module of the present invention will be described. The same components as those of the substrate structure shown in FIG. 3 are designated by the same reference numerals and the description thereof will be omitted.

As shown in FIG. 6, the substrate body 70 is bent into a U shape so that a top plate portion 58A and a bottom plate portion 58B are formed.
And a connecting portion 58C, and two conductive columns 64 and 71 are arranged between the top plate portion 58A and the bottom plate portion 58B. One of the columns 64 is a top plate portion 58.
The end of A and the end of the bottom plate portion 58B are fixed. The other pillar 71 is located between the pillar 64 and the connecting portion 58C, and separates the arbitrary electronic components 62 arranged on the mounting surface 58a from each other. Therefore, the pillar 71
Functions as a partition wall between the electronic components 62,
It is possible to efficiently absorb the electric field noise generated from the. Note that the number, position, shape, and size of the columns 71 are appropriately selected.

Here, the procedure for assembling the substrate body 70 will be described.

As shown in FIG. 7, a net-like shield portion 63 is applied to the back surface of a rectangular board body 70 made of a flexible printed board, an electronic component 62 is mounted on the mounting surface 58a, and a support is provided at one end of the board body 70. The support 64 is fixed, and the support 71 is fixed at an arbitrary position where the electronic components 62 are separated from each other.
After that, the substrate body 70 is bent through two parallel bending lines 68a and 68b which are provided at the center of the substrate body 70 and extend in the width direction. Then, by fixing the other end of the substrate body 70 to the upper surface of the support column 64, the connecting portion 58C
It is possible to dispose any strut 71 between and the strut 64.

Next, a third embodiment of the substrate structure of the optical module of the present invention will be described.

As shown in FIG. 8, the board body 80 is formed by bending the left and right sides of the flexible printed board into a U shape.
It is composed of first and second top plate portions 80A and 80B, a bottom plate portion 80C, and first and second connecting portions 80D and 80E. The respective connecting portions 80D, 80E are located at both ends of the bottom plate portion 80C, and the first and second top plate portions 80A, 8
0B and the bottom plate portion 80C are connected to each other. Furthermore,
A conductive column 82 fixed to the mounting surface 81 is arranged in the center of the bottom plate portion 80C. Then, the tip portion 80a of the first top plate portion 80A extending from the first connecting portion 80D.
And a second top plate portion 80B extending from the second connecting portion 80E.
The front end portion 80b of the column is fixed to the upper surface of the column 82. Therefore, the mounting surface 81 is divided into the left and right via the support column 82, and is formed in a U shape on the left and right to accommodate the electronic components 62 and 65.

In this case, a conductive mesh-like shield portion 87 is fixed over the entire outer surface 80c of the substrate body 80. Further, at the front end of the substrate body 80, the pillar 8
Two neck portions 83 and 84 are provided so as to sandwich 2, and head portions 85 and 86 are provided to each neck portion 83 and 84. Therefore, on the mounting surface 81, the circuit on the transmitting side and the circuit on the receiving side can be separated via the single column 82, and the assembling work of the substrate body 80 is extremely good. Further, after the assembling work of the board body 80, the circuit portion on the transmitting side and the circuit portion on the receiving side can be produced at the same time, and the work of fixing the board body 80 on the base body (not shown) is also simplified. .

Next, a fourth embodiment of the substrate structure of the optical module of the present invention will be described. The same or equivalent components as those of the first embodiment shown in FIG. 4 are designated by the same reference numerals, and the description thereof will be omitted.

As shown in FIG. 9, the substrate main body 90 has columns 6 which are arranged at the ends of the top plate portion 58A and the bottom plate portion 58C.
4 and the connecting portion 58C are provided with two neck portions 91, 92, and each neck portion 91, 92 has a head portion 93, 9
4 are provided. Therefore, since the circuit on the transmitting side and the circuit on the receiving side can be incorporated in one board main body 90, it is only necessary to fix one board main body 90 on one substrate 45, and the circuit board 8 can be assembled. Workability is improved.

Next, a fifth embodiment of the substrate structure of the optical module of the present invention will be described. The same or equivalent components as those of the second embodiment shown in FIG. 6 are designated by the same reference numerals, and the description thereof will be omitted.

As shown in FIG. 10, in the substrate body 100, one neck portion 10 is provided between the support column 71 and the connecting portion 58C which are arranged substantially at the centers of the top plate portion 58A and the bottom plate portion 58C.
1 is provided, and the other neck portion 102 is provided between the support column 64 and the support column 71 arranged at the ends of the top plate portion 58A and the bottom plate portion 58C. Then, each neck portion 101,
Head portions 103 and 104 are provided at 102.
Therefore, since the circuit on the transmitting side and the circuit on the receiving side can be incorporated with the strut 71 interposed therebetween in one substrate main body 100, the strut 71 serves as a partition for separating the transmitting side circuit unit and the receiving side circuit unit. The function is performed so that the electric field noise generated in a large amount from the circuit on the transmitting side is not picked up by the circuit on the receiving side. In addition, one substrate body 10 is provided on one substrate 45.
Since it is only necessary to fix 0, the workability of assembling the circuit board 8 is improved.

The present invention is not limited to the various embodiments described above. For example, the above-mentioned connecting portion is formed in a plate shape having a predetermined width, but is formed in a linear shape having no width. You may form. In this case, the top plate portion of the substrate body can be inclined from the support column toward the connecting portion, and the drainage property at the time of cleaning the optical module can be improved. Further, although not shown, by providing projecting pieces at both ends of a rectangular base body for fixing the substrate body, and sandwiching the projecting pieces by a pair of upper and lower hook pieces provided on the inner surface of each side wall of the housing 4,
The circuit board 8 can be appropriately fixed in the housing 4.

[0038]

The optical module according to the present invention has a small number of components because the mounting surface is provided on the inner surface of the bent substrate body for mounting electronic components and the conductive shield portion is provided on the outer surface of the substrate body. Thus, it is possible to take measures against noise due to the electric field, and moreover, the workability of assembling the optical module can be improved because the number of parts is reduced. Also,
The mounting area for mounting electronic components on the board body increases,
It has an excellent effect that the mounting efficiency of electronic parts can be improved.

[Brief description of drawings]

FIG. 1 is a perspective view showing an optical module to which a substrate structure of the present invention is applied.

FIG. 2 is an exploded perspective view of the optical module shown in FIG.

FIG. 3 is a perspective view showing a first embodiment of the substrate structure of the present invention.

4 is a perspective view showing a state in which lead pins are fixed to the circuit board shown in FIG.

5 is a perspective view showing a state before the board body of the circuit board shown in FIG. 4 is formed by bending.

FIG. 6 is a perspective view showing a second embodiment of the substrate structure of the present invention.

FIG. 7 is a perspective view showing a state before the substrate body shown in FIG. 6 is bent and formed.

FIG. 8 is a perspective view showing a third embodiment of the substrate structure of the present invention.

FIG. 9 is a perspective view showing a fourth embodiment of the substrate structure of the present invention.

FIG. 10 is a front view showing a fifth embodiment of the substrate structure of the present invention.

FIG. 11 is an exploded perspective view showing a conventional optical module.

[Explanation of symbols]

1 ... Optical module, 2, 3 ... Optical actuating element, 58, 59,
70, 80, 90, 100 ... Substrate body, 58a, 81 ...
Mounting surface (inner surface), 58b ... Outer surface, 58A, 80A, 80
B ... Top plate portion, 58B, 80C ... Bottom plate portion, 58C, 80
D, 80E ... Connecting portion, 62, 65 ... Electronic component, 63, 6
6 ... Shield part, 64, 67, 71 ... Prop.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location H04B 10/14 10/04 10/06

Claims (5)

[Claims] 1. A substrate structure of an optical module for mounting an optical actuation element and an electronic component for driving the optical actuation element, wherein a mounting surface is provided on an inner surface of a bent substrate body for mounting the electronic component, A substrate structure for an optical module, characterized in that a conductive shield portion is provided on the outer surface of the main body. 2. The substrate body is integrally formed of a top plate portion, a bottom plate portion, and a connecting portion, and one end of the top plate portion and one end of the bottom plate portion are connected via the connecting portion, 2. The substrate structure of the optical module according to claim 1, wherein the other end of the top plate portion and the other end of the bottom plate portion are fixed via conductive posts. 3. The substrate body is integrally formed of first and second top plate portions, a bottom plate portion, and first and second connecting portions, and the first and second top and bottom portions are provided at both ends of the bottom plate portion. And a front end portion of the first top plate portion extending from the first connection portion and a front end portion of the second top plate portion extending from the second connection portion. The substrate structure of the optical module according to claim 1, wherein the substrate is fixed to an upper surface of a pillar provided on the mounting surface of the part. 4. The substrate structure of an optical module according to claim 1, wherein the shield part has a mesh structure. 5. The substrate structure of an optical module according to claim 2, wherein the substrate body is made of a flexible printed board.