JP2009253176A - Photoelectric conversion module and optical subassembly - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photoelectric conversion module using a can package, which is easily mounted on an external circuit board so that a central axis of the package and an extending direction of the external circuit board are parallel. <P>SOLUTION: The photoelectric conversion module 1 includes electronic components mounted in a can package including a LD 2 and mounted on an external circuit board. The photoelectric conversion module 1 includes a pair of planar electric connecting members 8 penetrating the can package and extending in an axis direction of the can package. The pair of planar electric connecting members 8 have wiring patterns 8a drawn outside, connecting to the electronic components in the can package, and conductive elastic members 8b provided on outer drawing-out portions of the wiring patterns 8a, on each of surfaces facing against each other. The conductive elastic members 8b are connected to electrode pads formed on the external circuit board inserted between the pair of planar electric connecting members 8. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a photoelectric conversion module used for optical communication and an optical subassembly using the photoelectric conversion module.

  As a package of the photoelectric conversion module (optical module), a can (CAN) package is adopted from the viewpoint of assembling and handling of the module. The can package is formed, for example, by coaxially fixing a metal cylindrical cap having an optical window to a metal disc-like stem on which a photoelectric conversion element is mounted.

In the can module optical module, an electrical connection means for electrically connecting an element (photoelectric conversion element or the like) mounted in the package and a circuit board (external circuit board) outside the package is provided in the stem. This electrical connection means is used, for example, to exchange electrical signals between the photoelectric conversion element and the external circuit board, and is inserted into the through hole of the stem and sealed and held.
Patent Document 1 discloses an optical module using lead pins as electrical connection means. Patent Document 2 discloses an optical module using an insulating substrate having a plurality of wiring patterns as electrical connection means.
JP 2005-286305 A JP 2004-140387 A

  In the technique disclosed in Patent Document 1, a flexible printed circuit board (FPC) is used to attach an optical module to an external circuit board. When mounting, for example, a lead pin as an electrical connection means is cut to a desired length, the cut lead pin and one end of the FPC are soldered, and the external circuit board and the other end of the FPC are soldered. Thus, the optical module and the external circuit board are electrically connected. However, in this method, time is required for soldering work, lead pin cutting work, etc., and it is desired that the optical module can be more easily attached to the external circuit board.

  In the technique disclosed in Patent Document 2, an insulating substrate with a wiring pattern as an electrical connection means provided in a can package of an optical module is inserted into a through hole of an external circuit substrate, and an electrode portion is soldered. By attaching. This method assumes that the center axis (package axis) of the can package of the optical module and the extension direction (substrate extension direction) of the external circuit board are perpendicular to each other. It cannot be applied to an optical data link whose extending direction is parallel. Furthermore, in this method, an operation of soldering the electrode portions of the insulating substrate and the external circuit substrate is necessary, and the above-described problem relating to the ease of attachment occurs.

  The present invention has been made in view of the above-described circumstances, uses a can package, and is attached to an external circuit board so that the central axis of the package and the extending direction of the external circuit board are parallel to each other. It is an object of the present invention to provide a photoelectric conversion module and an optical subassembly including the same.

  In order to solve the above problems, a photoelectric conversion module of the present invention is a photoelectric conversion module in which an electronic component including a photoelectric conversion element is mounted in a can package and is mounted on an external circuit board, and penetrates the can package. And a pair of insulating substrates extending in the axial direction of the can package, and the pair of insulating substrates are led out to the outside of the can package to be electrically connected to the electronic components on each of the opposing surfaces. And an elastic terminal provided in an external lead-out portion of the wiring pattern, and the terminal is connected to an electrode pad formed on an external circuit board inserted between a pair of insulating substrates. It is electrically connected.

Further, the wiring pattern of the insulating substrate may be electrically insulated by an insulating plate in the through portion of the can package. Note that a coplanar line is preferably formed by three wiring patterns arranged in parallel on the insulating substrate, and the upper end surface of the insulating substrate is preferably a submount on which electronic components are mounted.
The photoelectric conversion module of the present invention can be used for an optical subassembly.

  According to the present invention, it is easy to attach the photoelectric conversion module and the external circuit board in the optical data link having a positional relationship in which the package axis of the photoelectric conversion module having the can package and the extending direction of the external circuit board are parallel to each other. .

  FIG. 1 is a diagram for explaining the outline of the photoelectric conversion module of the present invention. 1A and 1B are cross-sectional views of the photoelectric conversion module of this example when viewed from the front and side, respectively, and FIG. 1C is a perspective view of the photoelectric conversion module. is there. 1A to 1C, illustration of wire connection described later is omitted, and in FIG. 1C, illustration of a cap is omitted.

  A photoelectric conversion module (hereinafter referred to as an optical module) according to the present invention has a photoelectric conversion function. In this example, as shown in FIG. 1, a laser diode (LD: Laser Diode) is used as a photoelectric conversion element responsible for the photoelectric conversion function. ) 2 is an optical transmission module. The optical module 1 is formed by hermetically sealing elements such as an LD 2 and a monitor photodiode (PD: Photo Diode) 5 in a can package in which a cap 4 is fixed to a stem 3. A mount 6 and a prism (right angle prism) 7 are also accommodated. In addition, as an electrical connection means for electrically connecting an element such as LD2 and an external circuit board (not shown) outside the package, the optical module 1 includes a pair of plate-like electric elements in which a wiring pattern 8a is formed on a flat plate-like insulating substrate. A connection member 8 is provided, and each wiring pattern 8a has a conductive elastic member 8b as a connection terminal to the electrode pad of the external circuit board.

  In the optical module 1, an electrical signal is received from an external circuit board via the wiring pattern 8 a of the plate-like electrical connection member 8 and the conductive elastic member 8 b, and the received electrical signal is optically transmitted to the LD 2 mounted on the submount 6. And an optical signal is transmitted from the LD 2 toward the prism 7. Then, the transmitted optical signal is reflected by the reflecting surface of the prism 7 and is transmitted toward an optical fiber (not shown) via a lens 4 a attached to the cap 4. In the optical module 1, the monitor PD 5 mounted on the submount 6 monitors the rear light from the LD 2 (light from the surface opposite to the light transmission side where the light output is strong). In an optical communication device such as an optical transceiver equipped with the optical output, the optical output from the optical module 1 can be set to a desired value based on the monitored result.

  In such an optical module 1, the pair of plate-like electrical connection members 8 according to the features of the present invention has an extending direction parallel to the central axis O direction of the can package, and the member 8. A wiring pattern 8a is formed on each of the side surfaces facing each other. Further, a plurality of conductive elastic members 8b are provided so as to face each of the pair of plate-like electrical connecting members 8. The optical module 1 is electrically connected to the external circuit board by the elasticity of the conductive elastic member 8b in a state where the external circuit board for the optical module 1 is inserted between the opposing conductive elastic members 8b. It has become.

  With this configuration, the optical module 1 is attached to the external circuit board and electrically connected so that each conductive elastic member 8b contacts a predetermined electrode pad (terminal) on the external circuit board. The operation is completed only by inserting the external circuit board between the pair of plate-like electrical connecting members 8 from the center axis O direction of the package. In the state after the attachment, the central axis O of the package and the external circuit board are parallel. Further, in the present optical module 1, since the soldering operation or the like is not required for attachment to the external circuit board, the attachment is easy.

Next, each component of the optical module will be described with reference to FIG.
FIG. 2 is a view showing the appearance of the constituent members (excluding the plate-like electrical connecting member 8) of the optical module 1 of FIG. 2A shows the LD 2, FIG. 2B shows the stem 3, FIG. 2D shows the monitor PD 5, and FIG. 2E shows the submount 6, viewed from above and from the rear, respectively. It shows the state. FIG. 2C shows a cross section of the cap 4, and FIG. 2F shows the prism 7 as viewed from above and from the side. 3-5 is a figure explaining the plate-shaped electrical connection member 8, FIG. 3 (A) is a perspective view of the said member 8, FIG.3 (B) is the said member 8 seen from the side. It is a top view. FIG. 4A and FIG. 4B are three views of a base substrate and an insulating plate that constitute the plate-like electrical connection member, respectively. FIG. 5 is a cross-sectional view of the plate-like electrical connecting member 8 attached to the stem 3.

  As shown in FIG. 2A, the LD 2 is an edge-emitting (edge-emitting) LD, and is mounted on the metal pattern 6b on the upper surface 6a of the submount 6 by a conductive adhesive or the like. Light along the upper surface 6a of the submount 6 (that is, the upper surface 3a of the stem 3) is emitted from the exit surface 2a of the LD 2 (the surface on the prism 7 side). The dimensions of LD2 are, for example, a length L1 of 0.3 mm, a width W1 of 0.25 mm, and a thickness T1 of 0.1 mm.

  An electrode 2b is formed on the upper surface of the LD2, and an electrode is also formed on the lower surface of the LD2, although not shown. Therefore, when the LD 2 is mounted on the metal pattern 6b of the submount 6 as described above, the metal pattern 6b and the electrode on the lower surface of the LD 2 are electrically connected. One of the upper electrode 2b and the lower electrode of the LD 2 is an anode electrode, and the other is a cathode electrode. In this example, the upper electrode 2b is an anode electrode.

  The stem 3 is a disk-shaped member as shown in FIG. 2B, and is made of a metal material such as Kovar, for example. In the component mounting area of the stem 3, electronic components such as the LD 2 and the monitor PD 5 and optical components such as the prism 7 are mounted. A submount 6 is mounted on the upper surface 3 a of the stem 3, and the LD 2 and the monitor PD 5 are mounted on the metal pattern 6 b formed on the submount 6. That is, the electronic component is mounted on the stem 3 through the submount 6. The prism 7 is directly mounted on the stem 3.

  Further, the stem 3 is provided with a pair of through holes 3b for penetrating the plate-like electrical connection member 8, and the plate-like electrical connection member 8 is sealed and attached in a state of being inserted into the through-hole 3b. It is done. The region between the pair of through holes 3b (on the upper surface 3a) is the component mounting region described above. The dimensions of the stem 3 are a diameter Φ1 of 5.6 mm and a thickness T2 of 1.2 mm. The size (length L2 and width W2) of the through hole 3b of the stem 3 is slightly larger than the plate-like electrical connecting member 8, and the distance A1 between these through holes 3b is, for example, 1 0.5 mm.

  The cap 4 constitutes a CAN package having a cylindrical component mounting space inside in cooperation with the stem 3 and is formed using a metal material. Further, the cap 4 of this example is a lens cap including a lens 4a as an optical window and a cap shell 4b as shown in FIG. 2C. The lens 4a collects light from the LD 2 (light emitted from the LD 2 and reflected by the prism 7). The lens 4a is composed of, for example, a ball lens, and its diameter Φ2 is 1.5 mm. The shape (spherical surface or aspherical surface) or material of the lens is not limited.

  The cap shell 4b holds the lens 4a and has a shape in which a flange is provided at one end of a cylinder. The lens 4a is fixed to the opposite side of the cap shell 4b from the flange portion 4c by a sealing glass such as a low melting point glass. The cap shell 4b has a cylindrical portion having an inner diameter Φ3 of 4 mm and an outer diameter Φ4 of the flange portion 4c of 5.2 mm. The cap 4 is fixed to the stem 3 by adhering the end surface of the flange portion 4c of the cap 4 thus configured to the upper surface 3a of the stem 3 by laser welding or the like.

The monitor PD5 is of an end face incident type, and as a result, the backward light from the LD2 is transmitted to the LD2
The light can be received for feedback control. The monitor PD5 is also mounted on the metal pattern 6b on the upper surface 6a of the submount 6 similarly to the LD2. As shown in FIG. 2D, the monitor PD5 has a length L3 of 0.35 mm, a width W3 of 0.35 mm, and a thickness T3 of 0.15 mm, for example.

  Further, an electrode 5a is formed on the upper surface of the monitor PD5, and an electrode is also formed on the lower surface of the monitor PD5 (not shown). Therefore, when the monitor PD 5 is mounted on the metal pattern 6b of the submount 6 as described above, the metal pattern 6b and the electrode on the lower surface of the monitor PD 5 are electrically connected. One of the upper electrode 5a and the lower electrode of the monitor PD5 is an anode electrode, and the other is a cathode electrode. In this example, the upper electrode 5a is a cathode electrode.

  The submount (metallized substrate) 6 is used for mounting the LD 2 and the monitor PD 5 having electrodes formed on the lower surface thereof on the metal stem 3. For example, an insulating material having high thermal conductivity such as AlN is used. The insulating flat substrate used is used as the base. The submount 6 is mounted on the stem 3 with an adhesive material (form) having good thermal conductivity. Further, as shown in FIG. 2E, a thin film metal pattern 6b is formed on the upper surface 6a of the submount 6, and the LD 2 and the monitor PD are mounted on the metal pattern 6b. The metal patterns 6b are separated from each other. The dimensions of the submount 6 are, for example, a length L4 of 1.3 mm, a width W4 of 0.9 mm, and a thickness T4 of 0.3 mm.

  The prism 7 reflects light from the LD 2 emitted in a direction parallel to the upper surface 3a of the stem 3 toward the lens 4a. The prism 7 is made of, for example, a glass material BK7 and is formed in a prismatic body having an isosceles triangle having a substantially right-angled cross section, as shown in FIG. 2F. Is provided. The prism 7 is mounted on the submount 6 with, for example, a resin adhesive. In this example, the prism 7 has the above-mentioned pillars formed from a cube of 0.6 mm, and the dimensions of the prism 7 are 0.6 mm for the length L5, 0.6 mm for the width W5, and 0.5 mm for the thickness T5. It is 6 mm.

  The plate-like electrical connection member 8 according to the present invention is a plate-like member that electrically connects the LD 2 and the like to an external circuit board (drive electric circuit board), and is sealed and fixed to the through hole 3b of the stem 3. The pair of plate-like electrical connecting members 8 of the optical module 1 are the same as each other, and are each composed of a base substrate 8c and an insulating plate 8d smaller (shorter) than the base substrate 8c. In addition, as the base of the base substrate 8c and the insulating plate 8d, a flat plate-like electrically insulating substrate made of a ceramic material or the like is used.

  As shown in FIG. 4A, the base substrate 8c is formed with a plurality of wiring patterns 8a (four in the example shown in the figure) for electrical connection across the upper surface 8e and one side surface 8f. is there. The wiring pattern 8a on the upper surface 8e and the wiring pattern 8a on the side surface 8f are electrically connected by being physically continuous. The conductive elastic members 8b fixed to the wiring pattern 8a have the same shape, and are formed by forming an elastic conductive thin rectangular plate such as Kovar or SUS. The conductive elastic member 8 b is fixed so that the major axis direction thereof coincides with the major axis direction of the insulating flat substrate of the plate-like electrical connection member 8.

Further, the conductive elastic member 8b has the following shape by the forming. That is, the lower end (the side opposite to the optical module 1 side) which is a fixed portion to the wiring pattern 8a is bonded and fixed to the wiring pattern 8a, and the upper end is located far from the wiring pattern 8a. It is.
The base substrate 8c has dimensions of a length L6 of 2.7 mm, a width W6 of 0.5 mm, and a thickness (height) T6 of 6 mm.

The insulating plate 8d shown in FIG. 4B is an insulating unit that prevents the wiring pattern 8a of the base substrate 8c from being short-circuited to the stem 3 by not contacting the wiring pattern 8a of the base substrate 8c. The insulating plate 8d is attached (attached) to the portion of the base substrate 8c opposite to the conductive elastic member 8b side (upper side) with an adhesive or the like so as to cover the wiring pattern 8a. The electrical connection member 8 is produced.
The dimensions of the insulating plate 8d are a length L7 of 2.7 mm, a width W7 of 0.5 mm, and a thickness (height) T7 of 1.2 mm.

  As shown in FIG. 5, the plate-like electrical connection member 8 as described above is held by the stem 3 in such a form that its upper portion protrudes from the stem 3 into the can package. Therefore, the wiring pattern 8a on the upper surface 8e of the base substrate 8c of the plate-like electrical connection member 8 can be electrically connected to the electrode such as the LD2. As a result, the LD2 and the external circuit board can be electrically connected by bringing the conductive elastic member 8b provided in the wiring pattern 8a into contact with the terminal of the external circuit board.

  Moreover, as for a pair of plate-shaped electrical connection member 8, the electroconductive elastic member 8b has the above-mentioned shape by the said forming. Therefore, when held by the stem 3, the distance A2 (2.1 mm) between the conductive elastic members 8b on the lower side is larger than the thickness of the external circuit board, and the distance between the conductive elastic members 8b on the upper side. A3 is smaller than the thickness of the external circuit board, and the distance between the conductive elastic members 8b in the intermediate portion becomes smaller as it goes upward. Therefore, when the optical module 1 is attached to the external circuit board, it is possible to easily push the optical module 1 while the external circuit board is positioned between the pair of plate-like electrical connection members 8. After completion of the mounting), the optical module 1 can be fixed to the external circuit board by the elastic force of the pair of plate-like electrical connecting members 8.

  Moreover, in the technique disclosed in Patent Document 2, the optical module and the external circuit board are integrally fixed and attached, and their positional relationship cannot be adjusted after attachment. Even if it exists, the said positional relationship can be adjusted.

Next, referring to FIG. 6, an electrical connection form in the optical module 1 will be briefly described.
In the optical module 1 of this example, there are eight wiring patterns 8a. Of these, four are required for electrical connection. Therefore, as shown in FIG. 6, the wiring pattern 8a that minimizes the electrical connection wire is selected and connected. Of the four wiring patterns, the first is the anode electrode 2b of the LD2, the second is the metal pattern 6b of the submount 6 electrically connected to the cathode electrode of the LD2, and the third is the monitor. The cathode electrode 5a of the PD 5 and the fourth are electrically connected to the metal pattern 6b of the submount 6 electrically connected to the anode electrode of the monitor PD 5 by wiring.

  Next, another example of the optical module of the present invention will be described with reference to FIGS. FIGS. 7A and 7B are cross-sectional views of the optical module of this example when viewed from the front and side, respectively, and FIG. 7C is a perspective view of the optical module. FIG. 8 is a three-view diagram illustrating a set of plate-like electrical connection members of the optical module in FIG. 7, and FIG. 8A shows a base substrate of one plate-like electrical connection member, and FIG. ) Shows the base substrate of the other plate-like electrical connecting member. FIG. 9 is a plan view for explaining an electrical connection form in the optical module. In addition, regarding the optical module of this example, the same components as those of the optical module 1 in FIG.

  The optical module 10 in FIG. 7 differs from the optical module 1 in FIG. 1 in the elements mounted in the package, the form of the base substrate of the plate-like electrical connection member, the form of the submount, and the electrical connection form in the package.

  In addition to photoelectric conversion elements such as LD2 and monitor PD5, the optical module 10 includes a ferrite bead inductor (FBI) 11 used for a bias T circuit in a package. The FBI 11 is mounted on the upper surface 8e of the base substrate 12a of one plate-like electrical connecting member 12.

  The set of plate-like electrical connection members 12 of the optical module 10 is such that the position of the wiring pattern 8a on the upper surface 8e is that of the plate-like electrical connection member 8 shown in FIG. Are different. The set of plate-like electrical connecting members 12 are different from each other. As shown in FIG. 8 (A), an electrode pad 12b for electrical connection with the FBI 11 is formed on the base substrate 12a of one of the plate-like electrical connection members 12 (on which the FBI 11 is mounted). Is a submount on which electronic components are mounted. As shown in FIG. 8B, the base substrate 12a of the other plate-like electrical connecting member 12 has a coplanar line 12d having one wiring pattern 8a as a signal line and wiring patterns 8a on both sides thereof as a ground plane. Is formed. The wiring pattern 8a serving as the signal line is such that the cathode electrode of the LD 2 is electrically connected via a thin film resistor 13a of the submount 13 described later.

  Further, as in the submount 13 of the optical module 10, a flat insulating substrate made of AlN or the like is used as the base as in the submount 6 shown in FIG. ), Unlike the submount 6, in addition to the metal pattern 6b on which the LD2 and the monitor PD5 are mounted, a thin film resistor 13a used for the bias T circuit is formed on the upper surface 6a. In addition to the metal pattern 6b, the submount 13 is provided with an electrode pad 13b for electrically connecting the wiring pattern 8a of the plate-like electrical connecting member 12 and the LD 2 via the thin film resistor 13a. The In the submount 13, the metal pattern 6b on which the LD2 is mounted is connected to the electrode pad 13b via the thin film resistor 13a, and the metal pattern 6b on which the monitor PD5 is mounted is separated from the electrode pad 13b and the thin film resistor 13a. And therefore insulated from these.

  The electrical connection form in the optical module 10 is as follows. That is, as shown in FIG. 9, in the optical module 10, there are eight wiring patterns 8a, of which six are used for electrical connection. Of the six wiring patterns, the first wiring pattern 8a is the anode electrode 2b of the LD2, the second is the electrode pad 13b of the submount 13 electrically connected to the cathode electrode of the LD2, and the third is The cathode electrode 5a of the monitor PD5 and the fourth electrode are electrically connected to the metal pattern 6b of the submount 13 electrically connected to the anode electrode of the monitor PD5 by wiring.

  The fifth wiring pattern 8a is electrically connected to the wiring pattern 8a connected to the anode electrode 2b of the LD 2 by the conductive layer (wiring pattern) on the upper surface 8e of the plate-like electrical connecting member 12. The two wiring patterns 8a serve as a ground plane for the coplanar line 12c. The sixth wiring pattern 8a is electrically connected to one electrode of the FBI 11 by soldering or the like. The other electrode of the FBI 11 is electrically connected to the electrode pad 12b on the plate-like electrical connecting member 12 by soldering or the like, and this electrode pad 12b is a metal pattern of the submount 13 that is electrically connected to the cathode electrode of the LD2. It is electrically connected to 6b by wiring.

  As described above, in the optical module 10, by using the plate-like electrical connection member 12 as the electrical connection member, a coplanar line can be formed on the electrical connection member. It is also possible to incorporate a T circuit element. The plate-like electrical connecting member 12 can easily match high-frequency characteristics (impedance matching) by using a coplanar line. Therefore, the optical module 10 can perform high-frequency transmission of 2.5 Gbps or more.

  Next, other examples of the optical module of the present invention will be described with reference to FIGS. FIGS. 10A and 10B are cross-sectional views of the optical module of this example when viewed from the front and side, respectively, and FIG. 10C is a perspective view of the optical module. FIG. 11 is a three-view diagram for explaining the plate-like electrical connection member of the optical module of FIG. 10 and shows a base substrate of one plate-like electrical connection member. FIG. 12 is a plan view for explaining an electrical connection form in the optical module. In addition, regarding the optical module of this example, the same components as those of the optical module 1 of FIG. 1 and the optical module 10 of FIG.

  The optical module 20 shown in FIG. 10 includes components to be mounted in the package, the mounting form of these components, the form of the base substrate of the plate-like electrical connection member, the form of the submount, and the form of electrical connection in the package. Or different from the optical module 10 of FIG.

  In addition to the LD 2 and the monitor PD 5, the optical module 20 includes an electronic cooler (TEC: Thermoelectric cooler) 21 and a thermistor 22 in the package for adjusting the temperature of the LD 2. The TEC 21 is fixed on the stem 3 using an adhesive material having good thermal conductivity. Among the components other than the TEC 21 in the optical module 20, elements such as the LD 2, the monitor PD 5, and the thermistor 22 having electrodes on the lower surface are mounted on the TEC 21 via the submount 23, and the prism 7 is directly mounted on the TEC 21. Is done. In the optical module 20, all components are mounted from one direction.

As shown in FIG. 11, the set of plate-like electrical connecting members 24 of the optical module 20 includes the length (height) of the protruding portion into the package and the base substrate 24a so that the wires for electrical connection become shorter. The position of the wiring pattern 8a on the upper surface 8e is different from that described above. Further, the set of plate-like electrical connection members 24 have the same configuration as each other, and are formed so that the base substrates 24a are mirror surfaces.
Further, on the submount 23 of the optical module 20, as shown in FIG. 12, in addition to the metal pattern 6b on which the LD2 and the monitor PD5 are mounted, a metal pattern 6b on which the thermistor 22 is mounted is also formed on the upper surface 6a. ing.

  The electrical connection form in the optical module 20 is as follows. That is, in the optical module 20, all of the eight wiring patterns 8a are used for electrical connection, the first is the submount 23 electrically connected to the anode electrode 2b of the LD2, and the second is electrically connected to the cathode electrode of the LD2. The third metal pattern 6b is electrically connected to the cathode electrode 5a of the monitor PD5, and the fourth is electrically connected to the metal pattern 6b of the submount 23 electrically connected to the anode electrode of the monitor PD5, respectively. . The fifth wiring pattern 8a includes one electrode 21a of the TEC 21, the sixth electrode the other electrode 21a of the TEC 21, the seventh electrode of the upper surface 22a of the thermistor 22, and the eighth The metal pattern 6b of the submount 23 electrically connected to the electrode on the lower surface of the thermistor 22 is electrically connected by wiring.

  Currently, an optical module having a can package is required to be downsized as the device (for example, an optical data link) on which the module is mounted is downsized. In an optical module having a small package, when a lead pin is used as an electrical connection means as disclosed in Patent Document 1, the lead pin requires an insulating sealing portion for each pin, and there are many according to the number of elements to be mounted. Since it is required, the device mounting area in the can package has been limited.

  On the other hand, in the optical module 20 of this example, instead of the lead pins, the plate-like electrical connection member 24 in which a plurality of wiring patterns 8a are formed is held in the through hole 3b provided in the stem 3 and used as electrical connection means. Accordingly, the area occupied by the wiring in the package can be reduced while securing the number of wirings for electrically connecting the inside and outside of the package of the optical module. That is, in the optical module 20, even if it is a small can package, a component mounting area can be ensured. As a result, the optical module 20 can be equipped with a high-capacity TEC 21 or thermistor 22 as an element for stabilizing the optical output from the LD 2 regardless of temperature change or time change, and is also used for high-speed optical communication. be able to.

In the above three examples, an insulating plate is used as means for insulating the wiring pattern formed on the base substrate of the plate-like electrical connection member and the stem, and brazing is performed with the base substrate and the insulating plate being bonded together. Thus, the plate-like electrical connection member is held by the stem. However, the form of the plate-like electrical connection member itself and the fixing form of the member are not limited to this. For example, it is assumed that the plate-like electrical connecting member is composed only of the base substrate on which the above-described wiring pattern is formed, and glass is used when the plate-like electrical connecting member is fixed to the stem so that the wiring pattern and the stem are insulated. Sealing may be used, or an insulating material may be previously applied to the wiring pattern and fixed by brazing.
Further, the number of wiring patterns provided on the plate-like electrical connection member is eight in the above-described three examples. However, the number is not limited to this, and the number of wiring patterns may be increased or decreased as necessary.

  The optical module of the present invention described above with three examples is often used in the form of a receptacle type optical sub-assembly (OSA) and a pigtail type OSA described later.

  The receptacle type OSA is used for an SDH / SONET optical data link or the like. 13A includes an optical module (any one of 1, 10 and 20), a sleeve member 31 for guiding and receiving a ferrule of an optical fiber cable (not shown), and a sleeve member 31 for the optical module. And a joint sleeve (J sleeve) 32 for fixing these positions. The sleeve member 31 includes, for example, a fiber stub 33, a holder 34, an alignment sleeve 35, and a sleeve shell 36, and the J sleeve 32 includes an isolator 37 including a Faraday rotator, a polarizer, and a permanent magnet. Since the fiber stub 33 and the like are the same as those of the prior art, the description thereof is omitted. The J sleeve 32 may be the same as the J sleeve 42 of the pigtail type OSA 40 to be described later (that is, the J sleeve 32 may not have the isolator 37).

  The pigtail type OSA is used for optical analog transmission for relaying between CATV and mobile phone base stations, or used for a WDM transmission line card or the like. 10B includes an optical module (any one of 1, 10, and 20), an optical transmission member (pigtail) 41 having one end (not shown) as an optical connector and the other end connected to the optical module. And a J sleeve 42 for determining the position of the optical transmission member 41 with respect to the optical module and fixing them. The optical transmission member 41 includes, for example, an optical fiber cable 43, a ferrule 44, a protective cover 45, and a ferrule holder 46. Since the optical fiber cable 43 and the like are the same as those of the conventional one, the description thereof is omitted. The J sleeve 42 may be the same as the J sleeve 32 of the receptacle type OSA 30.

  FIG. 14 is a view showing a state where the pigtail type OSA 40 of FIG. 13B using the optical module 20 of FIG. 10 is mounted and attached to an external circuit board. FIG. 14A is a side view. FIG. 14B shows a state seen from the front.

  In the optical module 20 of the pigtail type OSA 40, as described above, the insulating substrates of the two plate-like electrical connecting members 24 face each other at a predetermined interval, and the wiring pattern 8a is provided on each of the opposing surfaces on the insulating substrate. And a conductive elastic member (contact terminal) 8b. When the optical module is mounted, the conductive elastic member 8b of the plate-like electrical connecting member 24 of the optical module 20 is connected to the external circuit with the external circuit board 50 (FIG. 11A) sandwiched between the facing surfaces. The optical module 20 is pushed into the external circuit board 50 so as to be in contact with the wiring 51 (terminal at the end) of the board 50. After the attachment is completed, each of the conductive elastic members 8b is in contact with and electrically connected to the corresponding terminal of the external circuit board 50 (that is, the conductive elastic member 8b sandwiches the terminal and is electrically connected to the terminal. And bend as shown in FIG. Therefore, an elastic force that fixes the optical module 20 to the external circuit board 50 is generated with respect to the optical module 20.

It is a figure explaining the outline of an example of the photoelectric conversion module of this invention. It is a figure which shows the external appearance of the structural member (except a plate-shaped electrical connection member) of the optical module of FIG. It is a figure explaining the plate-shaped electrical connection member of the optical module of FIG. It is a figure explaining the plate-shaped electrical connection member of the optical module of FIG. It is a figure explaining the plate-shaped electrical connection member of the optical module of FIG. It is a figure explaining the electrical connection form in the optical module of FIG. It is a figure explaining the outline of the other example of the optical module of this invention. FIG. 8 is a three-side view illustrating a set of plate-like electrical connection members of the optical module of FIG. 7. It is a top view explaining the electrical connection form in the optical module of FIG. It is a figure explaining the outline of the other example of the optical module of this invention. It is a three-plane figure explaining a set of plate-shaped electrical connection members of the optical module of FIG. It is a top view explaining the electrical connection form in the optical module of FIG. It is sectional drawing explaining OSA provided with the optical module of this invention. It is a figure which shows a mode when the pigtail type OSA of FIG.13 (B) using the optical module of FIG. 10 is mounted | worn with and attached to the external circuit board.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,10,20 ... Optical module, 2 ... Laser diode, 2b ... Anode electrode, 3 ... Stem, 3b ... Through-hole, 4 ... Cap, 4a ... Lens, 4b ... Cap shell, 4c ... Flange part, 5 ... Monitor PD 5a ... cathode electrode, 6, 13, 23 ... submount, 6b ... metal pattern, 7 ... prism, 8, 12, 24 ... plate-like electrical connection member, 8a ... wiring pattern, 8b ... conductive elastic member, 8c, 12a, 24a ... base substrate, 8d ... insulating plate, 11 ... ferrite bead inductor, 12b ... electrode pad, 12c ... coplanar line, ... submount, 13a ... thin film resistor, 13b ... electrode pad, 21 ... TEC, 21a ... electrode, 22 ... Thermistor.

Claims (5)

A photoelectric conversion module in which an electronic component including a photoelectric conversion element is mounted in a can package and mounted on an external circuit board,
Having a pair of insulating substrates that penetrate the can package and extend in the axial direction of the can package;
A wiring pattern led out to the outside electrically connected to the electronic component inside the can package, and elasticity provided in an external lead-out portion of the wiring pattern on each of the surfaces of the pair of insulating substrates facing each other Having a terminal,
The photoelectric conversion module, wherein the terminal is electrically connected to an electrode pad formed on the external circuit board inserted between the pair of insulating substrates.   2. The photoelectric conversion module according to claim 1, wherein the wiring pattern of the insulating substrate is electrically insulated by an insulating plate at a penetrating portion of the can package.   3. The photoelectric conversion module according to claim 1, wherein a coplanar line is formed by three wiring patterns arranged side by side on the insulating substrate.   The photoelectric conversion module according to claim 1, wherein an upper end surface of the insulating substrate is a submount on which the electronic component is mounted.   An optical subassembly comprising the photoelectric conversion module according to claim 1.

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