JP2003329894A - Card edge type optical communication module and optical communication equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inexpensive optical communication module having a card edge part. <P>SOLUTION: This optical communication module has at least either of a light emitting element or a light receiving element, an optical coupling means optically coupled to the element and an electric circuit component connected to the element. The element, the optical coupling means and the electric circuit component are mounted on a multilayer conductive medium. A portion of the conductive medium, the element, the optical coupling means and the electric circuit component are housed in a package 120. The card edge part 150 is projected from the package 120. The card edge part 150 has a connection part (lead 43) formed on the conductive medium exposed from the package 120 and an insulation part 44 for holding the connection part of respective layers. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical communication module used for optical communication and an optical communication device using the module. In particular, the present invention relates to an optical communication module in which a card edge portion can be configured at low cost without the need to connect it to a subsequent circuit by soldering.

[0002]

2. Description of the Related Art Japanese Unexamined Patent Publication 2001
-77455 is known. This is provided by disposing an optical element connected to the connection terminal and one end of an optical waveguide optically coupled to the optical element on a substrate having an optical element driving connection terminal at one end. , An optical communication module connectable to a connector is disclosed. According to this configuration, mechanical contact can be realized by inserting the optical communication module into the socket.

[0003]

However, in this optical communication module, the lead frame used is only one layer, the number of connection pins is physically limited, and it is difficult to realize multiple functions. In particular, the IC itself is also integrated, and for example, there is an IC that has a function to control the emission power as well as to drive an LD (laser diode), and it is difficult to sufficiently cope with the required number of connection leads. .

Further, connection terminals must be formed independently of the lead frame of the optical communication module and connected by bonding wires, and an expensive board or another component is required to form a card edge portion to be inserted into the connector. Is required.

Therefore, a main object of the present invention is to provide an inexpensive optical communication module having a card edge portion.

Another object of the present invention is to provide an optical communication module which can be connected to a subsequent circuit board without soldering and which can be easily replaced with respect to the subsequent circuit board.

Another object of the present invention is to provide an optical communication module excellent in heat dissipation. Furthermore, another object of the present invention is to provide an optical communication device using an inexpensive optical communication module having a card edge portion.

[0008]

The present invention achieves the above object by using a multi-layered conductive medium and forming a card edge portion in a part of the conductive medium.

That is, in the optical communication module of the present invention, at least one of a light emitting element and a light receiving element, an optical coupling means optically coupled to the element, an electric circuit component connected to the element, these elements, and an optical element. Conductive medium in which the mechanical coupling means and the electric circuit components are mounted, a part of the conductive medium, a package that accommodates the element, the optical coupling means and the electric circuit components, and a package protruding from the package It has a card edge part. The card edge portion is characterized by having a connecting portion formed on the conductive medium exposed from the package and an insulating portion holding the connecting portion of each layer.

By making the conductive medium multi-layered, it is possible to mount a large number of elements and electric circuit parts, which are largely restricted in mounting on the same plane. A plurality of light emitting elements, light receiving elements and electric circuit components may be mounted on the same conductive medium, or different light emitting elements may be mounted on different conductive media.
A light receiving element or an electric circuit component may be mounted.

The card edge portion is formed by using these multilayer conductive media. Therefore, it is not necessary to prepare another substrate for the configuration of the card edge portion, and the card edge portion can be constructed at low cost.

Further, by inserting the card edge portion into the connector of the rear circuit board, the optical communication module and the rear circuit board can be easily connected without using soldering. Therefore, when the optical communication module is damaged, it can be easily replaced or replaced with another optical communication module having a different type of mounted light emitting / receiving element or electric circuit component.

The present invention will be described in more detail below. LD is suitable for the light emitting element used in the present invention, and a photodiode (PD) is suitable for the light receiving element. Also, as the electronic circuit parts connected to these elements, LD driver ICs and
An amplifier (AMP) that amplifies a PD signal can be given. Further, the optical coupling means may be an optical fiber. Usually, an optical fiber with a ferrule is used.

A metal lead frame is suitable as the conductive medium. The number of layers of this lead frame may be two or three or more. Further, a plurality of light emitting / receiving elements and electric circuit parts may be installed on each conductive medium.

The card edge portion is constructed by using a part of this conductive medium. Generally, in an optical communication module, at least one of a light emitting element and a light receiving element, an electronic circuit component and an optical transmission medium are integrated in a resin-molded package. From this package, a part of an optical fiber ferrule or a part of a lead frame is integrated. One lead is protruding.
In the present invention, the conductive medium exposed to the outside of the package is used as the connecting portion to be connected to the connector of the subsequent substrate circuit, and the connecting portion of each layer is held by the insulating portion to form the card edge portion.

It is preferable that the card edge portion is configured to fit into the connector portion of the subsequent circuit board. As a result, the optical communication module and the subsequent circuit board can be connected without soldering by simply inserting the card edge portion into the connector. Further, since soldering is not performed, replacement is free, and a damaged optical communication module or an optical communication module having another function can be easily replaced. As the connector portion, any one can be used as long as the card edge portion is fitted therein and the contact portion comes into contact with the connection portion.

The connecting portion of the card edge portion preferably has a structure in which a plurality of leads are arranged in parallel. This connecting portion is preferably provided on at least one of the front and back of the card edge portion. For example, in the case of having two stages of connecting portions, an insulating portion is interposed between both connecting portions to form a single card edge portion having connecting portions on the front and back sides, or on the front or back surface of each connecting portion. An example is to integrate the insulating parts to form a pair of card edge parts. In this way, by configuring the connecting portion on at least one of the card edge portions, it is possible to freely arrange the conductive media in combination,
The optical communication module can be easily designed.

It is preferable that part of the connecting portion is connected to the heat radiation medium without being connected to the connector portion of the subsequent circuit board. Since the light emitting element, the light receiving element and the electric circuit parts are supported by the multilayer conductive medium,
A sufficient number of leads can be secured for each. Therefore, some of the leads can be used for heat dissipation.

Various materials having high thermal conductivity can be used for the heat dissipation medium connected to the connection portion. For example, sircon (heat conductive sheet made of mica or polyamide resin) and metal are suitable. The connecting portion may be in direct contact with the heat-dissipating medium, or may be in contact with a heat-dissipating plate. A material similar to the heat dissipation medium can be used for the heat dissipation plate.

The insulating portion is preferably made of a material having electrical insulation and thermal insulation. As a result, the heat radiation from the card edge portion can be concentrated from the connection portion, and the heat radiation can be efficiently performed.

The form of the optical communication module includes an optical transmitting module, an optical receiving module and an optical transmitting / receiving module. An example of the optical transmission module is one using an LD as a light emitting element and an LD driver IC as an electric circuit component. Further, it may be an optical transmission module using a monitor photodiode (M-PD) that detects the light intensity of the LD. An example of the optical receiving module is one that uses a PD as a receiving element and an AMP that amplifies a signal of the PD as an electric circuit component. The optical transmission / reception module includes one having at least one set of light emitting element and driver IC, and at least one set of light receiving element and amplifier.

In the present invention, at least one of the light emitting element and the light receiving element and the electric circuit component are supported by the conductive medium, either directly on the conductive medium or indirectly through some material such as a Si bench. Including both when supporting.

At least one of the light emitting element and the light receiving element is preferably supported on the conductive medium via a Si bench. Si has excellent thermal conductivity, and the heat generated by the light emitting element and the light receiving element can be effectively dissipated from the conductive medium via the Si bench. In addition, the Si bench can easily be formed with a V groove for holding an optical fiber by etching.

On the other hand, the electric circuit components such as the driver IC and the amplifier are preferably supported on a conductive medium different from the conductive medium supporting at least one of the light emitting element and the light receiving element. By directly providing the electric circuit component on a conductive medium different from the light emitting / receiving element, the heat generated by the electric circuit component can be quickly dissipated through the different conductive medium.

The optical communication device of the present invention is characterized in that the above-mentioned optical communication module is connected to a common rear circuit board in multiple stages at right angles. With this configuration, the post-stage circuit board can be shared by the plurality of optical communication modules, and the optical communication device having the optical communication module and the post-stage circuit board can be made inexpensive and compact.

[0026]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below. (Embodiment 1) FIG. 1A is a plan view of an optical communication module of the present invention, FIG. 1B is a front view thereof, and FIG. 2 is a perspective view thereof.

In this module 100, a card edge portion 150 is provided at one end of a thin block-shaped package 120 molded with epoxy resin or the like, and an optical fiber ferrule 62 is provided at the other end. This card edge part 150
Is formed by interposing an insulating portion 44 between two leads 43 projecting outside the package 120.

The internal structure of this module will be described with reference to FIG. FIG. 3 is a vertical sectional view of the module of the present invention.

This optical transmission module is a light emitting element.
An LD 10 and a driver IC 20 of the LD 10 which is an electric circuit component are provided. LD10 is the first lead frame 41 via the Si bench 30.
And the driver IC 20 is directly supported on the second lead frame 42 which is laminated so as to overlap a part of the first lead frame 41. An insulating spacer 50 is interposed between the first and second lead frames. Then, a shallow V groove and a deep V groove are continuously formed on the Si bench 30, and an optical fiber 61 is fitted in the shallow V groove and an optical fiber ferrule 62 is fitted in the deep V groove.

The characteristics of the LD 10 (for example, LD having InGaAsP grown on InP as an active layer) are sensitive to temperature, and it is desirable to avoid heat from the driver IC 20 (for example, IC of Si or GaAs) as much as possible. On the other hand, by shortening the distance between the LD 10 and the driver IC 20, it becomes possible to operate at higher speed. Therefore, as shown in FIG. 3, the LD chip is arranged on the first lead frame 41, and the driver IC 20 is arranged on the second lead frame 42.

On the other hand, the lead frames 41, 4 are provided on the end surface of the module 100 opposite to the optical fiber ferrule 62.
The lead 43 which is a part of 2 is projected. An insulating portion 44 is filled between the two leads to form a card edge portion 150. Each lead 43 constitutes a contact portion of the card edge portion 150, which becomes a contact when inserted into the connector. Here, a plurality of strip-shaped leads are arranged in parallel to form a contact portion. The contact portions are provided on both the front surface side and the back surface side of the insulating portion 44, and project from the front surface or the rear surface of the insulating portion.

Although the above description has been given of the optical transmission module, the optical receiving module can be constructed by replacing the LD with the PD and the driver IC with the preamplifier. Then, the optical transmitter-receiver module can be constructed by enclosing the optical transmitter module and the optical receiver module in parallel in a single package.

Such an optical transmitter module can be obtained as follows. First, an insulating spacer 50 made of a polymer insulating material having a low thermal conductivity and a good electric insulating property is used, and the two lead frames 41 and 42 are separated by a predetermined distance (here, about 1 mm).
And place it. The insulating spacer 50 is preferably made of liquid crystal polymer, and the lead frames 41, 42 are preferably made of Fe, Cu, Al or the like.

The LD 10 is mounted on the Si bench 30 which also serves as a heat sink and submount. Since the Si bench 30 is a semiconductor and conducts electricity, the front and back surfaces of the Si bench 30 can be made of SiO ₂ by thermal oxidation or the CVD method.
The insulating layer 31 is formed. Also, by photolithography, the V groove and LD1 for fixing the optical fiber 61 and the ferrule 62 (made of zirconia or alumina) that holds the optical fiber 61
A metallization pattern for bonding 0 is formed on the Si bench 30.

Next, between the LD 10 and the driver IC 20, the driver
The IC 20 and the lead frames 41, 42 are connected by bonding an Au wire 70. After that, the space including the LD 10, the driver IC 20, and the end of the optical fiber is potted with, for example, a transparent silicone resin. This allows the optical fiber 61
Refractive index matching with, end face protection of LD10 and driver IC20, Au
Functions such as protection of the wire 70 can be secured. Then, the package 120 is formed by molding the whole of the ferrule 62 excluding the tip end portion with an epoxy resin. At that time, 2
The card edge portion 150 is also configured by filling the insulating portion 44 between the leads 43 of one sheet. The rectangular broken line in Fig. 3 shows the outline of the resin-molded package.
The broken line of the curve covering the IC indicates the contour of potting with the transparent resin.

Such an optical communication module can be connected to the subsequent circuit board 200 by inserting it into the connector shown in FIG. The rear circuit board 200 has a connector 220 at one end thereof parallel to the board 210. The connector 220 is a rectangular plate having a fitting hole that exactly fits the card edge portion. Inside the fitting hole, a large number of contacts that make surface contact with the contact portion are arranged in parallel. By using the optical communication module provided with the card edge portion 150 in this manner, connection / disconnection with the subsequent circuit board 200 can be easily performed, and replacement work of the optical communication module can be easily performed.

(Embodiment 2) Next, a module of the present invention in which the card edge portion has two stages will be described. FIG. 5 is a front view of an optical communication module having a two-stage card edge portion, and FIG. 6 is a perspective view thereof.

As shown in FIGS. 5 and 6, a pair of optical fiber ferrules 62 are provided on one end of a thin block-shaped package 120.
Is common to the first embodiment, but is different from the first embodiment in that the card edge portions 150 are formed in two stages on the other end side of this package. That is, as shown in FIG. 7, a four-layered lead frame is used, and the insulating portion 44 is filled between each pair of leads to form the card edge portion 150.

The internal structure of this module is shown in FIG.
This module has a two-stage card edge portion, but the internal structure of the upper card edge portion is the same as in FIG. In this example, an electronic circuit for higher-level electrical signal processing is mounted on the card edge portion in the lower stage. That is, the integrated circuit element 21 for performing high-level electrical signal processing is mounted on one lead of the lower card edge portion, and the other electronic component 22 such as a resistor and a capacitor is mounted on the other lead. With this configuration, it is possible to electrically connect the light-emitting (light-receiving) element mainly at the upper card edge portion and perform more advanced electric signal processing at the lower card edge portion to connect to the subsequent circuit board.

The connection between the module 100 and the rear circuit board 200 may be made by inserting the connectors into the respective rear circuit boards 200, as shown in FIG. For example, of the two card edge portions 150, it is preferable to use the upper portion as the card edge portion of the optical transmission module and the lower portion as the card edge portion of the optical receiving module. By thus dividing the card edge portion 150 into a transmitting circuit board and a receiving circuit board, it is possible to use the transmitting circuit board and the receiving circuit board in the connected rear circuit board 200, respectively, and it is possible to freely arrange the circuit of the rear circuit board. You can have a degree.

Further, modified examples of the optical communication module having a two-stage card edge portion are shown in FIGS.

FIG. 10 is a partial plan view of an optical communication module using a three-layer lead frame. The insulating section 44 is formed on the upper surface of the upper lead 43 to form the first-stage card edge section 150, and the insulating section 44 is formed between the middle and lower leads 43 to form the second-stage card edge section 150. Has been formed.
For example, it is advisable to use the second card edge portion having the middle and lower leads for a complicated circuit having a large number of pins, and use the first card edge portion having the upper lead for a simple circuit. It is also convenient to use the upper lead as a terminal for inspection during the manufacturing process.

FIG. 11 is a partial plan view of an optical communication module using a two-layer lead frame. The insulating portion 44 is formed on the lower surface of the upper lead 43 to form the card edge portion 150 of the first step, and the insulating portion 44 is formed on the upper surface of the lower lead 43 to form the card edge portion 150 of the second step. ing. This configuration is particularly effective, for example, when it is desired to widen the card edge portions so that heat on the transmitting side is not transmitted to the receiving side.

As shown in FIGS. 6, 10, and 11, card edge portions having various configurations can be formed depending on the total number of lead frames used.

(Embodiment 3) FIG. 12 shows a module of the present invention in which a pair of card edge portions are arranged in parallel on the same surface. FIG. 12 is a plan view of a module of the present invention in which a pair of card edge portions are juxtaposed on the same surface, and FIG. 13 is a perspective view thereof.

FIG. 1 shows an optical communication module having a single card edge portion continuous in the width direction, but in this example, a pair of card edge portions are provided, one for transmitting and the other for receiving. .

The internal structure of this module is shown in FIG.
FIG. 14 is a perspective view showing the internal structure of the module of the present invention before the package is formed by molding.

As shown in FIG. 14, the LD 10 faces the one optical fiber ferrule 62, and the PD 80 faces the other optical fiber ferrule 62. This LD
A driver IC 20 is connected to 10 and a preamplifier 90 is connected to PD 80. Then, the card edge portion can be formed by interposing the insulating portion between the leads which are a part of each lead frame.

(Embodiment 4) Next, FIG. 15 shows an optical communication module of the present invention in which a part of the connection portion at the card edge is used for heat dissipation. FIG. 15 is an explanatory diagram showing a state in which the module of the present invention is mounted on a heat dissipation housing.

Here, four lead frames are used,
An optical communication module having two card edge portions is shown as an example. Of the two card edge portions, the upper card edge portion 150 is fitted into the connector 220 of the rear circuit board 200. On the other hand, the lower card edge portion 150 is not connected to the rear circuit board, and the connection portion is a heat dissipation medium.
It is in contact with 170. Various materials can be used for the heat dissipation medium 170 as long as it has a high thermal conductivity. For example, sircon and metal are suitable. Although the block-shaped heat dissipation medium is shown here, the heat dissipation medium 170 may be provided with fins for heat dissipation to further improve the heat dissipation performance. The heat dissipation medium itself is mounted in the heat dissipation housing 190 having good heat dissipation.

Since the number of leads can be sufficiently increased by using the multi-layered lead frame, some of the leads can be used for heat dissipation. That is, by bringing the leads protruding from the lid of the package into contact with the heat dissipation medium, efficient heat dissipation can be performed via the leads and the heat dissipation medium.

(Embodiment 5) Next, an optical communication device using the optical communication module of the present invention will be described. The optical communication modules described above are preferably arranged in multiple stages and connected to the subsequent circuit board 200, as shown in FIG. This latter circuit board 2
00 is provided with a plurality of connectors 220 in multiple stages in a direction perpendicular to the substrate 210. By inserting the card edge portion of the optical communication module 100 shown in Embodiments 1 to 4 into each connector 220, a plurality of optical communication modules can be connected to a single substrate. That is, the rear circuit board 200 can be shared by the plurality of optical communication modules 100, and the entire combination of the optical communication module and the rear circuit board can be made compact and inexpensive.

[0053]

As described above, according to the optical communication module of the present invention, the following effects can be obtained.

By utilizing a part of the multi-layered conductive medium, the card edge portion can be manufactured at a low cost, and a compact and multifunctional optical communication module can be obtained.

The optical communication module having the card edge portion eliminates the need for soldering and connecting to the subsequent circuit board.

Since the optical communication module itself does not need to be soldered to the subsequent circuit board and can be easily attached to and detached from the connector, the optical communication module itself can be easily inspected.

Since the card edge portion is provided, replacement is easy when the optical communication module fails.

Since the card edge portion is provided, it becomes easy to replace the light emitting / receiving element or the electric circuit component mounted on the optical communication module with another optical communication module.

Since the card edge portion can be formed by freely combining the multi-layered conductive media, the optical communication module can be easily designed.

By using a multi-layered conductive medium, a sufficient number of leads can be secured, and by using a part of the leads for heat dissipation, the heat dissipation of the optical communication module can be improved.

[Brief description of drawings]

1A is a plan view of an optical communication module of the present invention, and FIG. 1B is a front view thereof.

FIG. 2 is a perspective view of an optical communication module of the present invention.

3 is a vertical cross-sectional view of the optical communication module of FIG.

FIG. 4A is a perspective view showing a state in which the optical communication module of the present invention is inserted into a connector, and FIG. 4B is a front view thereof.

FIG. 5 is a front view of an optical communication module including a two-stage card edge portion.

FIG. 6 is a perspective view of the module shown in FIG.

FIG. 7 is a perspective view showing a card edge portion in the module of FIG.

8 is a cross-sectional view showing the internal structure of the module of FIG.

9A is a perspective view showing a state in which the optical communication module of FIG. 6 is inserted into a connector, and FIG. 9B is a front view of the same.

FIG. 10 is a partial plan view of an optical communication module using a three-layer lead frame.

FIG. 11 is a partial plan view of an optical communication module using a two-layer lead frame.

FIG. 12 is a plan view of a module of the present invention in which a pair of card edge portions are arranged in parallel on the same surface.

FIG. 13 is a perspective view of the module shown in FIG.

FIG. 14 is an internal configuration diagram of the module shown in FIG.

FIG. 15 is an explanatory diagram showing a usage pattern of the module of the present invention in which a part of the card edge portion is used for heat dissipation.

16A is a perspective view showing a state where the optical communication module of FIG. 12 is inserted into a connector, and FIG. 16B is a front view thereof.

[Explanation of symbols]

10 LD 20 Driver IC 21 Integrated circuit element 22 Other electronic components 30 bench 31 insulating layer 41 lead frame 42 lead frame 43 lead 44 Insulation part 50 insulating spacer 61 optical fiber 62 ferrule 70 bonding wire 80 PD 90 preamplifier 100 modules 120 packages 150 Card edge part 170 Heat dissipation medium 190 Heat dissipation housing 200 Rear circuit board 210 substrate 220 connector

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H04B 10/135 10/14 F term (reference) 2H037 AA01 BA02 BA11 BA31 DA03 DA04 5F073 AB15 AB28 BA02 FA02 FA13 FA27 FA28 FA29 FA30 GA02 5F088 AA01 BA15 BA16 BB01 EA07 EA16 JA03 JA06 JA10 JA14 JA20 5K102 AA11 PB02 PH32

Claims (6)

[Claims] 1. At least one of a light emitting element and a light receiving element, optical coupling means optically coupled to this element, electric circuit parts connected to the element, and these elements, optical coupling means and electric circuit parts. A multi-layered conductive medium on which is mounted, a part of the conductive medium, a package that houses the element, the optical coupling means, and an electric circuit component, and a card edge portion that projects from the package, An optical communication module, wherein the card edge portion has a connecting portion formed on the conductive medium exposed from the package, and an insulating portion holding the connecting portion of each layer. 2. The optical communication module according to claim 1, wherein the card edge portion is configured to be fitted into a connector portion included in a subsequent circuit board. 3. The connection part is provided on at least one of the front and back of the card edge part.
The optical communication module described in 1. 4. The optical communication module according to claim 1, wherein a part of the connection section is connected to the heat dissipation medium without being connected to the connector section of the subsequent circuit board. 5. The optical communication module according to claim 1, wherein the insulating portion is made of a material having electrical insulation and thermal insulation. 6. An optical communication device, wherein the optical communication module according to any one of claims 1 to 5 is connected to a common rear circuit board in a direction perpendicular to the same and in multiple stages.