JP2006011092A - Optical module, and ceramic substrate for optical module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical module which can be lowered in height and smaller in size and can be optically coupled to an optical fiber with high efficiently. <P>SOLUTION: The optical module 41 has a module main part 42 and an optical element 81. The optical module 41 can be coupled by a push-on fastening system to an MT ferrule 24 for an optical fiber connector. A ferrule support 27 for the optical fiber connector and a guide pin 31 for the optical fiber connector are used for coupling by the above system. The optical element 81 is disposed in the module main part 42 and is optically aligned when the MT ferrule 24 and the module main part 42 are coupled by the insertion of the guide pin 31. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an optical module having a photoelectric conversion function and a characteristic of a connection structure with an optical fiber connector, and a ceramic substrate used as a component of such an optical module.

  In recent years, with the development of information communication technology represented by the Internet and the dramatic improvement in the processing speed of information processing apparatuses, there is an increasing need for transmitting and receiving large-capacity data such as images. An information transmission speed of 10 Gbps or higher is desirable to exchange such a large amount of data freely through an information communication facility, and great expectations are placed on optical communication technology as a technology that can realize such a high-speed communication environment. On the other hand, in recent years, it has been desired to increase the speed of signal transmission over a relatively short distance, such as connection between wiring boards in a device or connection between LSI chips in a wiring board. For this reason, it is considered that the transition from the conventional metal cable or metal wiring to the optical transmission using an optical fiber or an optical waveguide is ideal.

  In optical transmission using an optical fiber or the like as a signal transmission path, an optical element that converts an optical signal into an electrical signal or an optical element that converts an electrical signal into an optical signal is usually used. As a structure for connecting such an optical element and an optical fiber, for example, a method using a guide pin and a clamp spring has been conventionally proposed (for example, see Patent Document 1). The apparatus described in Patent Document 1 includes a flat optical package that accommodates optical elements and LSI chips, and a flat optical fiber connector provided at the tip of a multi-core optical fiber. The optical fiber connector is laminated on the upper surface of the optical package. The optical package and the optical fiber connector each have a guide pin hole for alignment. And by inserting a guide pin into each guide pin hole and fastening with a clamp spring, the optical package and the optical fiber connector are detachably fixed to the wiring board in a vertical direction. . In this state, the optical element and the optical fiber connector are optically coupled.

Further, as another structure for connecting the optical element and the optical fiber, for example, a method using a housing structure instead of the above-described clamp spring has been proposed (for example, see Patent Document 2). The device described in Patent Document 2 includes a photoelectric conversion module including an optical element and an optical fiber connector provided at the tip of a multi-core optical fiber. This photoelectric conversion module has a housing structure at the tip, and the tip of the optical fiber connector can be accommodated in the housing structure. An alignment hole and a peg are formed in the photoelectric conversion module and the optical fiber connector. And a photoelectric conversion module and an optical fiber connector are fixed so that attachment or detachment is possible by fitting a peg in each hole part in the accommodation state in a housing structure part. In this state, the optical element and the optical fiber connector are optically coupled.
JP 2003-207694 A (FIG. 1 etc.) US Pat. No. 6,459,843

  However, in the prior art described in Patent Document 1, in addition to adopting a structure in which optical fiber connectors are stacked and arranged on an optical package, a structure in which a clamp spring is further mounted on the upper side thereof is adopted. Therefore, the entire apparatus becomes large in the direction perpendicular to the wiring board, and there is a drawback that it is difficult to achieve a reduction in height.

  Further, in the conventional technique described in Patent Document 2, since it is necessary to provide a housing structure part in a part of the photoelectric conversion module, it is inevitable to increase the size of the photoelectric conversion module. Therefore, a large space is required when mounting the photoelectric conversion module on the wiring board, which is very disadvantageous in achieving high-density mounting.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an optical module that can easily achieve an overall reduction in height and size and can be optically coupled to an optical fiber with high efficiency. There is. Another object of the present invention is to provide a ceramic substrate for an optical module suitable for realizing the above optical module.

  As a means for solving the above-mentioned problems, it is possible to connect to a ferrule for an optical fiber connector by a push-on fastening method using a ferrule support for an optical fiber connector having a locking portion and a guide pin for an optical fiber connector. There is provided an optical module comprising: a simple module main body; and an optical element that is provided in the module main body and that is optically aligned when the ferrule and the module main body are coupled by insertion of the guide pin.

  Therefore, according to the above means, by adopting the push-on fastening method for mechanical coupling between the ferrule and the module main body, it is not necessary to provide a housing structure part in a part of the module main body. Miniaturization is easy to achieve. In addition, it is not necessary to adopt a stacked arrangement structure that is an obstacle to the reduction in height. Furthermore, when the ferrule and the module main body are mechanically coupled by inserting the guide pins, the optical axes of the optical fibers and the optical elements are aligned. For this reason, although it is a comparatively simple method, an optical fiber and an optical element can be optically coupled with high efficiency.

  The “optical fiber connector” is a component used when connecting optical fibers, and specific examples thereof include an optical fiber MT connector. The “optical fiber MT connector” refers to an F12 type multi-core optical fiber connector specified in JIS C 5981 established in 1993 and revised in 1998. This standard number is based on JIS C 5982 and defines a clamp spring fastening structure and a connector of a plug (plug) -guide pin-plug coupling system aligned with a guide pin. As an equivalent international standard corresponding to JIS C 5981, there is IEC 60874-16 revised in 1994.

  An “optical fiber connector ferrule” is a precision component that is a constituent element of an optical fiber connector plug. Specific examples thereof include an MT ferrule. “Guide pin for optical fiber connector” is essentially a component that aligns the optical axes of two ferrules by inserting them into a guide pin hole of a ferrule. As a specific example thereof, an optical fiber MT connector is used. There are guide pins for use. Such a guide pin is made of stainless steel and has a length of 10.8 mm or more and a diameter of about 0.7 mm.

  The “push-on fastening method” refers to the following, for example. That is, when there is a ferrule support for an optical fiber connector that supports the ferrule for an optical fiber connector, an optical module formed separately from the optical module is pressed (pushed) to the support side and slid to lock the support. This means that the support and the optical module are fastened by locking the portion by being locked to the locked portion of the optical module. Conversely, the optical module is pulled (pulled) and slid in the opposite direction, and the locking portion of the support body is detached from the locked portion of the optical module to release the lock, so that the support body and the optical module are released. It can also be understood that this is a method of separation (so-called pull-off method). Regarding the push-on fastening method as described above, for example, JIS C 5982 has a similar rule.

  In the above-described means employing the push-on fastening method, an urging means for applying an urging force for pressing the ferrule toward the optical module is disposed between the rear end face of the ferrule for the optical fiber connector and the ferrule support. It is preferable. This is because, according to this structure, the urging force of the urging means acts at the time of push-on fastening, and the ferrule and the optical module are firmly fastened. As this type of biasing means, an elastic body such as a leaf spring or a coil spring is suitable.

  The module body constituting the optical module may have approximately the same shape and approximately the same dimensions as the optical fiber connector ferrule. More specifically, the module main body may be formed in a substantially rectangular parallelepiped shape like the ferrule for optical fiber connector. For example, when the optical fiber connector ferrule is an MT ferrule, the dimension along the guide pin insertion direction (X-axis direction for convenience) is defined as 8.0 mm. The dimension along the optical fiber alignment direction (for convenience, the Y-axis direction) is defined as 6.4 mm to 7.0 mm, and the direction orthogonal to the X-axis direction and the Y-axis direction (for convenience, the Z-axis direction). )) Is defined as 2.5 mm to 3.0 mm. Therefore, the dimension of the module body in the X-axis direction is preferably set to 8.0 mm ± 0.3 mm, for example. The dimension of the module body in the Y-axis direction is preferably set to 6.0 mm to 8.0 mm, for example. The dimension of the module body in the Z-axis direction is preferably set to 2.0 mm to 4.0 mm, for example.

  When the module main body is configured in this way, the optical module is surely downsized and is suitable for mounting on a small wiring board, so that high-density mounting is possible.

  The module main body has a front end surface and a rear end surface. The front end surface of the module main body is disposed to face the front end surface on the ferrule side, and two guide pin holes into which guide pins can be inserted are formed to be spaced apart from each other. On the other hand, the rear end surface of the module main body is located on the side opposite to the front end surface. The reason for providing the guide pin hole at this position is as follows. That is, the ferrule side guide pin hole is formed in the ferrule tip end surface (that is, the exposed end of the optical fiber), and the module main body side guide pin hole needs to be disposed on the surface facing it. The module main body side guide pin holes are preferably formed corresponding to positions where the respective ferrule side guide pin holes are provided. Here, in JIS C 5981, the inner diameter of the ferrule side guide pin hole is defined as 7.0 mm ± 0.001 mm, and the pitch of the ferrule side guide pin hole is defined as 4.6 mm ± 0.003 mm. Therefore, in order to achieve reliable optical axis alignment, the inner diameter of the module body side guide pin hole is set to 7.0 mm ± 0.001 mm, and the pitch of the module body side guide pin hole is 4.6 mm ± 0.003 mm. It is preferable to set to.

  The ferrule support constituting the optical module is a structure that supports the ferrule for an optical fiber connector, and is formed separately from the optical module. Such ferrule supports are provided with one or more locking portions. As a suitable example of such a ferrule support, there may be mentioned one provided with a pair of support arms that are spaced apart so as to sandwich the ferrule and provided with a locking portion inside the front end portion of the support arms. Moreover, although the shape of a latching | locking part can be set arbitrarily, it is formed, for example in hook shape.

  The pair of support arms in the ferrule support is arranged in contact with two surfaces perpendicular to the tip surface of the ferrule. In this case, the thickness of the ferrule support may be approximately the same as the thickness of the ferrule (that is, the dimension in the Z-axis direction), and specifically, it may be set to 2.0 mm to 4.0 mm. This is to surely achieve a low profile. Further, as a material for the ferrule support, for example, a resin material is suitable. Specific examples thereof include engineering plastics such as PPS (polyphenylene sulfide), PBT (polybutylene terephthalate), and PEI (polyetherimide). . This is because the resin is generally flexible and is convenient when engaging and disengaging the locking portion. Therefore, the resin ferrule support is advantageous when the optical module is formed using a non-flexible material such as ceramic. Note that the material of the ferrule support is not limited to resin, and may be a metal such as stainless steel or aluminum. However, from the viewpoint of cost reduction, the resin is generally superior.

  Further, the locking portion of the ferrule support is locked or detached from a predetermined portion (for example, a locked portion) of the optical module. Such a locked portion is formed, for example, in a convex shape or a concave shape on the outer surface of the optical module.

  The optical module includes an optical element (such as a light emitting element or a light receiving element) that is optically aligned when the ferrule and the module body are coupled by inserting a guide pin. Here, the light emitting element refers to an optical element having a light emitting portion. Specific examples thereof include a light emitting diode (LED), a semiconductor laser diode (LD), and a surface emitting laser (Vertical Cavity Surface). Emitting Laser (VCSEL). The light emitting element has a function of converting an input electrical signal into an optical signal and then emitting the optical signal from a light emitting unit toward a predetermined portion. On the other hand, the light receiving element refers to an optical element having a light receiving portion, and specific examples include a pin photodiode (pin PD), an avalanche photodiode (APD), and the like. The light receiving element has a function of making an optical signal incident on the light receiving unit, converting the incident optical signal into an electric signal, and outputting the electric signal. Examples of suitable materials used for the optical element include Si, Ge, InGaAs, GaAsP, and GaAlAs. The “optical element whose optical axis is aligned” refers to an optical element whose optical axis is aligned with respect to an optical fiber provided in the ferrule.

  In this case, the optical element is preferably provided inside the optical module so as not to be exposed from the outer surface of the optical module. This is because the optical device can be reliably protected and can contribute to the improvement of reliability as compared with the configuration in which the optical device is exposed on the outer surface of the optical module.

  In addition to the optical element, the module body may be provided with at least one of a semiconductor integrated circuit element for driving the optical element and a semiconductor integrated circuit element for amplifying the optical signal, for example. That is, when the optical element is a light emitting element, the module body may be provided with a light emitting element and a semiconductor integrated circuit element (so-called driver IC) for driving the light emitting element. When the optical element is a light receiving element, the module main body may be provided with a light receiving element and a semiconductor integrated circuit element for optical signal amplification (so-called receiver IC). With such a configuration, for example, the conduction distance can be shortened and the operation speed can be increased compared to a case where a semiconductor integrated circuit element is provided outside the optical module and the optical element is electrically connected to the optical module. . Of course, in the case of an optical module having both a light emitting element and a light receiving element, the module body may be provided with both a semiconductor integrated circuit element for driving the optical element and a semiconductor integrated circuit element for amplifying the optical signal.

  In this case, it is preferable that the semiconductor integrated circuit element for driving the optical element or for amplifying the optical signal is provided inside the optical module so as not to be exposed from the outer surface of the optical module. This is because the semiconductor integrated circuit element can be reliably protected and can contribute to improvement in reliability as compared with the structure in which the semiconductor integrated circuit element is exposed on the outer surface of the optical module.

  Further, the module body may be provided with electronic components and elements other than the optical element and the semiconductor integrated circuit element. Specific examples of the electronic component include a chip transistor, a chip diode, a chip resistor, a chip capacitor, and a chip coil. These electronic components may be active components or passive components. Specific examples of the element include a thin film transistor, a thin film diode, a thin film resistor, a thin film capacitor, and a thin film coil. These elements may be active elements or passive elements. In this case, by providing a chip capacitor or a thin film capacitor, it is possible to reduce the resistance and the inductance, so that it is easy to realize high performance of the optical module.

  It is preferable that the module body is mainly composed of a material having higher heat dissipation (that is, a material having a higher thermal conductivity) than a resin material used for an optical fiber connector (that is, a ferrule and a ferrule support). The reason is described below. When an optical element is operated, heat is generated, but resin materials used for ferrules and the like are generally not very heat-dissipating, so that the heat cannot be efficiently dissipated to the outside, which causes instability of operation. Cause. On the other hand, if the module main body is mainly composed of a high heat dissipation material, heat can be efficiently dissipated to the outside and stable operation can be obtained. Preferable examples of the material having higher heat dissipation than the resin material used for ferrules and the like include inorganic materials such as metals and ceramics.

  It is preferable that the module main body is mainly composed of a ceramic (that is, a ceramic substrate) formed in a substrate shape. This is because heat can be efficiently dissipated to the outside if the module body is mainly composed of such a structure. Specific examples of suitable ceramic substrates in this case include alumina substrates, beryllia substrates, mullite substrates, aluminum nitride substrates, silicon nitride substrates, boron nitride substrates, silicon carbide substrates and the like. Those listed here are particularly excellent in heat dissipation.

  More preferably, the module body is mainly composed of a ceramic wiring substrate, and particularly preferably is composed mainly of a multilayer ceramic wiring substrate. Since such a wiring board is provided with a conductor layer and an insulating layer, electrical connection between the optical element and other components can be easily achieved using the conductor layer.

  The ceramic substrate has a substrate main surface, a substrate back surface located on the opposite side of the substrate main surface, and a plurality of side end surfaces perpendicular to the substrate main surface. A hole constituting at least a part of the guide pin hole is formed in one of the plurality of side end surfaces. More preferably, a filling recess is formed in a side end surface perpendicular to the main surface of the ceramic substrate, a filler made of a material having better workability than the ceramic substrate is filled in the filling recess, and the filler is guided. It is preferable to form a precision machined hole that constitutes at least a part of the pin hole. With such a configuration, since the guide pin hole is a precision machined hole, the optical axis of the optical fiber and the optical element can be more accurately aligned, and the optical coupling efficiency can be reliably improved. . Ceramics have the advantage of being excellent in heat dissipation and dimensional stability, but have the disadvantage of being hard and inferior in workability. For this reason, it is difficult to directly process a ceramic substrate to provide a precision processing hole, which leads to high costs. On the other hand, a precision drilled hole formed by subjecting a filler made of an easily processable material to precision drilling can be obtained relatively easily and at low cost. In addition, as a specific method for forming the precision processed hole, there are a drilling process, a punching process, a laser processing, and the like, but in consideration of cost and the like, a drilling process using a precision drill is most preferable.

  As the filler, it is preferable to select a resin material, a metal material, a glass material, or the like having a lower hardness than the ceramic substrate and good workability, and it is particularly preferable to select a resin material. This is because the resin material generally has a lower hardness than the ceramic material, so that labor and cost required for processing can be reduced. Moreover, since resin materials are generally cheaper than ceramic materials, they are also suitable for cost reduction.

  In addition, the module main body includes a support contact surface that can be contacted by a part of the ferrule support and is perpendicular to the tip surface, and the ferrule support contact surface includes the support of the ferrule support. It is preferable that a locked portion that can be engaged and disengaged is provided. Examples of such a locked portion include a locked protrusion formed in a convex shape and a locked recess formed in a concave shape. If the structure is such that the locking portion of the ferrule support is locked to the locked portion with irregularities, the coupling between the ferrule and the optical module can be made more reliable, for example, the deviation of the optical axis due to rattling or the like Can also be prevented. The locked protrusion and the locked recess are preferably formed integrally with the module body. In addition, the to-be-latched part which can engage / disengage a latching | locking part may be provided in the rear-end surface, for example.

  The optical element and the semiconductor integrated circuit element may be disposed on the same surface side of the ceramic substrate or may be disposed on different surface sides. When the latter configuration is employed, for example, the optical element is preferably disposed on the side end face side of the ceramic substrate, and the semiconductor integrated circuit element is preferably disposed on the substrate main surface side of the ceramic substrate. According to this configuration, since the light emitting surface or the light receiving surface of the optical element faces the X-axis direction, it is possible to achieve optical coupling with an optical fiber without performing optical path conversion. For example, a flexible substrate may be used in order to conduct between the optical element and the semiconductor integrated circuit element arranged on different surfaces.

  In the module body, a metal body may be provided on a surface other than the front end surface and the rear end surface, for example, on the upper end surface. With such a metal body, heat dissipation is further improved, so that heat of the optical element and the semiconductor integrated circuit element can be efficiently dissipated to the outside. Therefore, it becomes easy to achieve operation stabilization of the optical module. In addition, since it is possible to use a highly functional semiconductor integrated circuit element, it is easy to achieve an improvement in the performance of the optical module. Furthermore, the optical element and the semiconductor integrated circuit element are shielded from external electromagnetic waves, and as a result, the operation of the optical module is stabilized. Examples of the material of the metal body include copper, copper alloy, iron, nickel, iron-nickel alloy, and aluminum. The metal body is formed using, for example, a plate shape, a foil shape, or a layer shape using such a material. The metal body may be a bump connected to a substrate side on which the optical module is to be mounted. With such a heat dissipation bump, the heat of the optical element and the semiconductor integrated circuit element can be efficiently dissipated to the substrate side.

  In the module main body, a plurality of electrical connection terminals may be provided on a surface other than the front end surface and the rear end surface, for example, on the lower end surface. According to this configuration, electrical connection with the substrate side on which the optical module is to be mounted can be easily achieved. The form of the electrical connection terminal is not particularly limited, and examples thereof include bumps, pads, leads, and the like.

  The optical module may be provided with a microlens array which is a component having a light collecting function. When there is a microlens array, light transmission loss is reduced by collecting light. When a microlens array is employed, a spacer member for adjusting the focal length may be further provided.

  Further, as another means for solving the above-described problem, the optical fiber connector MT ferrule has a locking portion in a state in which the exposed end surface of the optical fiber in the MT ferrule is abutted with its own front end surface. A module main body that can be coupled using a support for optical fiber connector and a guide pin for optical fiber connector, and light provided when the MT ferrule and the module main body are coupled by insertion of the guide pin. There is an optical module including an optical element that is aligned with an axis.

  Therefore, according to the above means, when mechanically coupling the MT ferrule and the module main body, an arrangement mode is adopted in which the exposed end surface of the optical fiber in the MT ferrule and the front end surface of the module main body are abutted. For this reason, the dimension of the Z-axis direction at the time of coupling | bonding of both can be suppressed reliably, and it becomes easy to achieve the height reduction of the whole apparatus. Further, when the ferrule and the module main body are mechanically coupled by inserting the guide pin, the optical axis of the optical fiber and the optical axis of the optical element are also aligned. For this reason, although it is a comparatively simple method, an optical fiber and an optical element can be optically coupled with high efficiency. In this case, it is preferable that the upper surface of the ferrule and the upper surface of the optical module are substantially flush when the ferrule and the optical module are coupled.

  As a means for solving the above-mentioned another problem, a push-on fastening method is used for an optical fiber connector ferrule by using an optical fiber connector ferrule support having a locking portion and an optical fiber connector guide pin. There is a ceramic substrate for an optical module that is used in a connectable optical module, and is provided with a locked portion to which the ferrule locking portion can be engaged and disengaged.

  In addition to being excellent in heat dissipation, dimensional stability, and cost performance, the optical module ceramic substrate of the above means includes a locked portion. Therefore, if this ceramic substrate is used, the above excellent optical module can be easily realized. In this case, the locked portion is preferably formed integrally on the outer surface of the optical module. That is, the integrally formed locked portion is stronger in strength than the locked portion formed separately and can withstand a large load. Moreover, it is also possible to avoid an increase in the number of parts that causes a high cost.

  The ceramic substrate for an optical module includes, for example, a step of preparing a ceramic unsintered body having a convex part or a recessed part that will later become a part of the locked part, and firing the ceramic unsintered body to sinter the ceramic It is possible to manufacture through the process of making a body. And according to this manufacturing method, since a convex part or a recessed part is formed in the unsintered stage, a to-be-latched part can be integrally formed comparatively easily and cheaply.

  More specifically, the ceramic substrate for an optical module is provided with a plurality of green sheets, and a step of forming a convex portion or a concave portion that later becomes a part of the locked portion on the plurality of green sheets; A step of laminating the plurality of green sheets so that convex portions or concave portions are overlapped to produce a green ceramic laminate, and firing the green ceramic laminate to form a ceramic sintered body. And a step of integrally forming the locked portion.

  The ceramic substrate for an optical module of the above means has a substrate main surface and a side end surface perpendicular to the substrate main surface, and a filling recess is formed in the side end surface, and the filling recess is processed more than the substrate material. It is preferable that a filler made of a good material is filled, and the precision processing hole which is the guide pin hole is formed in the filler. According to such a configuration, the guide pin serving as a reference when aligning the optical axis can be reliably fitted into the precision machined hole, and as a result, the optical axis can be aligned more accurately. Therefore, if this ceramic substrate is used, the above excellent optical module can be easily realized.

  The ceramic substrate for an optical module, for example, a step of preparing a ceramic unsintered body having a filling recess that opens at a side end surface, a step of firing the ceramic unsintered body to form a ceramic sintered body, Producing through a step of filling a filler in the filling recess in the ceramic sintered body and a step of forming a hole in the guide pin hole by drilling the filler. Is possible. According to this manufacturing method, since the hole processing is performed in an unsintered stage, the guide pin hole can be formed relatively easily and inexpensively.

  More specifically, the ceramic substrate for an optical module is prepared by preparing a plurality of green sheets, forming a notch near the side end face, and laminating the plurality of green sheets to form an unsintered ceramic laminate. A step of forming a filling recess that opens at a side end surface by overlapping the notch, firing the green ceramic laminate to form a ceramic sintered body, Manufacturing through a step of filling the filler into the filling recess in the ceramic sintered body and a step of forming a hole in the filler to form at least a part of the guide pin hole. Is preferred.

[First Embodiment]

  Hereinafter, a first embodiment of the present invention will be described in detail with reference to FIGS.

  FIG. 1 is a schematic front view showing a state in which an optical module 41 of this embodiment is mounted on a printed wiring board 11 and an optical fiber connector MT ferrule 24 as an optical fiber connector ferrule is connected. FIG. 2 is a schematic top view showing the printed wiring board 11, the optical module 41, the MT ferrule 24, the multi-core optical fiber 26, and the guide pins 31 for the optical fiber connector. FIG. 3 is an exploded perspective view showing the MT ferrule 24 and the optical module 41. FIG. 4 is a perspective view showing an optical module ceramic substrate 51 constituting the module main body 42. FIG. 5 is a plan view of the optical module 41. 6 is a cross-sectional view taken along line AA in FIG. 7 is a cross-sectional view taken along line BB in FIG.

  As shown in FIG. 1 and the like, a printed wiring board 11 for mounting an optical module is a so-called multilayer board having a plurality of insulating layers 15 and a plurality of conductor layers (not shown), and has a front surface 12 and a back surface 13. is doing. A plurality of pads (not shown) are formed on the surface 12 of the printed wiring board 11, and two optical modules 41 are bump-connected on these pads. The optical module 41 located on the right side in FIG. 1 is a light emitting side optical module that converts an electrical signal into an optical signal. The optical module 41 located on the left side in FIG. 1 is a light receiving side that converts an optical signal into an electrical signal. It is an optical module. In addition to the optical module 41, the IC chip 16 and the like are similarly bump-connected to the surface 12 of the printed wiring board 11.

  As shown in FIGS. 1 to 3, the MT ferrule 24 of the present embodiment is supported by a flexible resin ferrule holder 27 (a ferrule support for an optical fiber connector). The ferrule holder 27 includes a pair of spaced apart support arms 25 and a connecting portion 28 that connects the support arms 25 at the base end portion, and has a substantially U-shape as a whole. With this structure, the optical module 41 can be coupled to the MT ferrule 24 by a push-on fastening method. Further, the thickness of the ferrule holder 27 is set to be substantially the same as that of the MT ferrule 24 (about 3.0 mm). On the inner side of the distal end portions of the both support arms 25, a collar portion 33 (locking portion) that can be engaged with and disengaged from the locked protrusion 60 integrally formed with the optical module 41 is provided. Further, the MT ferrule 24 is disposed between the support arms 25 so as to be slidable along the X-axis direction (that is, the guide pin insertion direction). Two coil springs 29 (biasing means) are disposed between the connecting portion 28 of the MT ferrule 24 and the rear end surface of the ferrule holder 27. These coil springs 29 serve to press the ferrule holder 27 in the direction of the optical module 41 when the optical module 41 is coupled.

  Further, the MT ferrule 24 includes a stepped portion 32 on the proximal end side, and a movement restricting stepped portion 30 is formed at a position corresponding to the stepped portion 32 on the inner surface of the pair of support arms 25. . Accordingly, the engagement of the two step portions 32 with these movement restricting step portions 30 prevents the MT ferrule 24 from being detached from the pair of support arms 25. Furthermore, as shown in FIG. 3, a part of the upper surface and a part of the lower surface of the ferrule holder 27 are each covered with a thin cover 36. These covers 36 prevent the MT ferrule 24 from being detached from the ferrule holder 27 in the Z-axis direction (that is, the vertical direction).

  2, 3, 5, 6, and 7, the optical module 41 of the present embodiment includes a ceramic substrate 51, a flexible substrate 76, a lid 72 (metal body), and a microlens array 73. The module main body 42 including the spacer 74 is provided. The optical module 41 has a substantially rectangular parallelepiped shape and is designed so that the dimensions of each part are substantially the same as those of the MT ferrule 24. Specifically, the dimension of the optical module 41 in the X-axis direction (left-right direction in FIG. 6) is set to 8.0 mm. The dimension of the optical module 41 in the Y-axis direction (vertical direction in FIG. 5) is set to 7.0 mm. The dimension of the optical module 41 in the Z-axis direction (vertical direction in FIGS. 4 and 6) is set to 3.0 mm. The module body 42 is mainly composed of a ceramic material (described later) having a higher heat dissipation than the resin material used for the MT ferrule 24 and the ferrule holder 27.

  As shown in FIGS. 4, 6, and 7, the ceramic substrate 51 that is the main body of the module body 42 is a multilayer alumina wiring substrate having a plurality of ceramic insulating layers 52 and a plurality of conductor layers 57. In the ceramic substrate 51, a through-hole conductor 58 is formed for conducting different layers of conductor layers 57. Cavities 59 are formed on the upper end surface 55 (substrate main surface) side and the lower end surface 56 side of the ceramic substrate 51, respectively. A capacitor 83 is accommodated in the cavity 59 on the lower end surface 56 side. For one optical module 41, a driver IC 82 as a semiconductor integrated circuit element for driving an optical element is accommodated in a cavity 59 on the upper end surface 55 side of the ceramic substrate 51. As for the other optical module 41, a receiver IC as a semiconductor integrated circuit element for optical signal amplification is accommodated in a cavity 59 on the upper end surface 55 side of the ceramic substrate 51. Note that the gap formed in the cavity 59 may be filled with, for example, a silicone resin 84 or the like. Moreover, in order to improve heat dissipation, the gap may be filled with thermal grease.

  A flexible substrate 76 made of polyimide resin is bonded to the upper end surface 55 of the ceramic substrate 51, and a lid 72 made of white and white is further bonded thereon. The lid 72 is a metal plate having a thickness of about 0.5 mm, and has an area substantially equal to the area of the upper end surface of the optical module 41. The driver IC 82 and the VCSEL 81 (optical element) are bump-connected to one side surface of the flexible substrate 76. These are electrically connected via a wiring pattern of the flexible substrate 76. A part of the flexible substrate 76 protrudes from the first side end surface 53 perpendicular to the upper end surface 55 and is bent at a right angle so as to be along the first side end surface 53. Accordingly, the VCSEL 81 is disposed on the first side end surface 53 of the ceramic substrate 51, and the light emitting surface thereof faces the X-axis direction of the optical module 41. On the other hand, since the driver IC 82 is in the cavity 59 on the upper end surface 55 side of the ceramic substrate 51, it can be grasped that the driver IC 82 is substantially disposed on the upper end surface 55 of the flexible substrate 76.

  A flat microlens array 73 made of a transparent material is attached to the first side end face 53 side of the ceramic substrate 51 via a square frame spacer 74. The spacer 74 is formed of, for example, a resin material or metal material having solder heat resistance. The VCSEL 81 has a plurality of (in the present embodiment, twelve) light emitting sections, and the microlens array 73 is provided with a plurality of microlenses corresponding to these. The light emitting unit and the microlens are both arranged in a straight line along the Y-axis direction of the optical module 41.

  As shown in FIGS. 2, 4, 5 and 7, two filling recesses 61 having a rectangular cross section are formed in the first side end surface 53 of the ceramic substrate 51 of the present embodiment. The filling recesses 61 are filled with a filler 63 made of a resin material having better workability than the ceramic substrate 51. The filler 63 is formed with a precision machining hole 62 having a circular cross section. There are two precision machining holes 62, both of which are opened at the first side end face 53 of the ceramic substrate 51. The precision machining holes 62 are formed corresponding to the positions of the two ferrule side guide pin holes 22 in the MT ferrule 24. Accordingly, the pitch of the precision machining holes 62 is equal to the pitch of the ferrule side guide pin holes 22 and is set to 4.6 mm ± 0.003 mm. The inner diameter of these precision machining holes 62 is equal to the inner diameter of the ferrule side guide pin hole 22 and is set to 7.0 mm ± 0.001 mm. Further, a through hole 70 having an inner diameter of 7.0 mm ± 0.001 mm and a pitch of 4.6 mm ± 0.003 mm is formed at a position corresponding to the precision machining hole 62 in the flexible substrate 76. In the microlens array 73, through holes 85 having an inner diameter of 7.0 mm ± 0.001 mm and a pitch of 4.6 mm ± 0.003 mm are formed at positions corresponding to the precision machining holes 62.

  In the module main body 42, the precision machining hole 62 and the through holes 70 and 85 communicate with each other, and as a result, a module main body side guide pin hole 80 is formed as a guide pin hole. That is, the module main body 42 of the present embodiment is provided with two module main body side guide pin holes 80 opened at the tip end face 43. The depth of the module main body side guide pin hole 80 is about 3.0 mm in this embodiment.

  2-5, the ceramic substrate 51 is provided with the 2nd side end surface 54 (support body contact surface) with which the inner side of a pair of support arm 25 can contact. The second side end face 54 is in a positional relationship perpendicular to the tip end face 43 of the module body 42, the upper end face 55 of the ceramic substrate 51, and the first side end face 53. And the to-be-latched protrusion 60 (latched part) which can engage / disengage the collar part 33 of a pair of support arm 25 is integrally formed in the 2nd side end surface 54. As shown in FIG. The protruding amount of the locked protrusion 60 gradually increases from the front end surface 43 to the rear end surface 44 of the module main body 42. That is, the dimension of the optical module 41 in the Y-axis direction is maximum at a position where the tip of the locked protrusion 60 is present.

  As shown in FIGS. 2 and 3, the optical fiber tip exposed surface 23 where the tip of the multi-core optical fiber 26 is exposed in the MT ferrule 24 and the tip surface 43 of the module body 42 are parallel to each other. It is faced. In this state, one end of the guide pin 31 is inserted and fixed in the ferrule side guide pin hole 22, and the other end of the guide pin 31 is inserted and fixed in the module body side guide pin hole 80. As a result, the MT ferrule 24 is mechanically coupled to the optical module 41 by a push-on fastening method. At the time of such coupling, the multi-core optical fiber 26 held by the MT ferrule 24 and the VCSEL 81 of the optical module 41 are optically aligned. In the present embodiment, specifically, a guide pin “CNF125A-21” (diameter 0.699 mm) defined in JIS C 5981 is used. Further, the MT ferrule 24 and the optical module 41 are sandwiched and fixed between the pair of support arms 25 of the MT ferrule 24.

  As shown in FIGS. 3, 6, 7, etc., a plurality of solder bumps 75 as a plurality of electrical connection terminals are provided in an array on the lower end surface 56 of the ceramic substrate 51. The optical module 41 is electrically connected to the surface 12 of the printed wiring board 11 through these solder bumps 75.

  The general operation of the apparatus configured as described above will be briefly described.

  Electric power is supplied from the printed wiring board 11 side to the optical module 41 having a light emitting element, and the VCSEL 81 and the driver IC 82 are operable by this electric power supply. An electric signal input from the printed wiring board 11 side is first input to the driver IC 82. Then, the driver IC 82 outputs a predetermined electric signal to the VCSEL 81 via the wiring pattern of the flexible substrate 76. The VCSEL 81 converts the input electrical signal into an optical signal (laser light), and then emits the optical signal toward the distal end surface of the multi-core optical fiber 26. The emitted optical signal passes through the transparent or translucent flexible substrate 76 and is then collected when passing through the microlenses of the microlens array 73. The condensed light is incident on each core of the multi-core optical fiber 26 held by the MT ferrule 24 and travels toward the light receiving side optical module 41.

  Next, a method for manufacturing the optical module 41 will be described.

  First, the ceramic substrate 51 is manufactured by the following procedure. A raw material slurry is prepared by uniformly mixing and kneading alumina powder, organic binder, solvent, plasticizer, etc., and this raw material slurry is used to form a sheet with a doctor blade device to produce a plurality of green sheets with a predetermined thickness. Form. Next, a through hole, a cutout portion, and a convex portion are formed on a predetermined portion of the green sheet by, for example, punching. Such a notch part later constitutes a part of the filling recess 61 and is formed so as to open at the side end face of the green sheet. Moreover, this convex part will comprise a part of to-be-latched protrusion 60 later, and is formed in an elongated triangular shape. In this case, it is possible to simultaneously form the through-hole hole, the notch portion, and the convex portion using the same mold, and according to this method, the three members can be formed efficiently and at low cost. Next, a metal paste (for example, tungsten paste) for through-hole conductors is filled in the through-hole holes, and a printed layer to be a conductor layer later is formed on the surface of the green sheet. Then, the plurality of green sheets are laminated. In that case, it arrange | positions so that notch parts may overlap and convex parts may overlap. And it presses with a predetermined pressure, each green sheet is integrated, and it is set as an unsintered green sheet laminated body. Next, after performing a drying process, a degreasing process, etc. according to a well-known method, a baking process is performed at the heating temperature (for example, 1650 degreeC-1950 degreeC) which an alumina can sinter further. As a result, the unsintered green sheet laminate is sintered to form the ceramic substrate 51, the filling recess 61 that opens at the first side end surface 53 is formed, and the second side end surface 54 is locked. The protrusion 60 is integrally formed.

  Next, with respect to 80 parts by weight of a bisphenol F type epoxy resin (“Epicoat 807” manufactured by JER) and 20 parts by weight of a cresol novolac type epoxy resin (“Epicoat 152” manufactured by JER), a curing agent (“Shikoku Kasei Kogyo Co., Ltd.” 2P4MZ-CN ") 5 parts by weight, 200 parts by weight of silica filler (" TSS-6 "manufactured by Tatsumori) treated with a silane coupling agent (" KBM-403 "manufactured by Shin-Etsu Chemical Co., Ltd.), defoaming agent (manufactured by Sannopco) "Berenol S-4") is mixed. This mixture is kneaded with three rolls to form a filler 63 for filling the filling recess 61. That is, the filler 63 of the present embodiment includes an inorganic filler in a thermosetting resin. Then, the filling material 63 is filled into the filling recess 61 by a conventionally known method (for example, a printing method), and is heated at 120 ° C. for 1 hour, so that the filling material 63 is semi-cured. Here, the reason why the filler 63 is not completely cured is to perform the hole processing in the next process more easily.

  Subsequently, precision drilling using a precision drill is performed to form precision drilled holes 62 in the semi-cured filler 63. According to such a hole machining method, the guide pin hole 80 which becomes an accurate reference for optical axis alignment can be obtained easily and reliably. In addition, since the hole processing is performed on the resin material, labor and cost required for the processing can be reduced, and the cost of the optical module 41 can be reduced. Here, the surplus filler 63 protruding from the opening of the filling recess 61 may be removed by setting the ceramic substrate 51 in a surface polishing apparatus and polishing the first side end face 53.

  Next, a main curing process is performed in which the ceramic substrate 51 is heated at 150 ° C. for 5 hours to completely cure the filler 63. Further, finishing is performed by a well-known method, and fine adjustment is performed so that the hole diameter of the precision machining hole 62 becomes 0.700 mm. Specifically, the accuracy required for processing at this time is ± 0.001 mm. As a result, the optical module ceramic substrate 51 is completed. The completed ceramic substrate 51 is further provided with solder bumps 75 by a conventionally known method.

  Next, a procedure for manufacturing the optical module 41 by attaching other components to the ceramic substrate 51 will be described. In this case, the flexible substrate 76 is prepared, and the VCSEL 81 and the driver IC 82 are mounted in advance on one side surface. Then, the ceramic substrate 51, the flexible substrate 76, the spacer 74, and the microlens array 73 are arranged in this order, and the guide pins 31 are inserted into the precision processing holes 62 and the through holes 70 and 85. As a result, the flexible substrate 76 and the microlens array 73 are fixed to the ceramic substrate 51 while being aligned. Next, the flexible substrate 76 is bent at a right angle, and the bent portion is bonded to the upper end surface 55 of the ceramic substrate 51 with an anisotropic conductive film. Further, a lid 72 is adhered thereon with a silver epoxy adhesive. It is also possible to electrically connect the conductor on the flexible substrate 76 side and the conductor on the ceramic substrate 51 side by means such as conductive paste, conductive film, or soldering. As a result, an optical module 41 with guide pins 31 as shown in FIG. 2 is obtained. Thereafter, the optical module 41 is soldered onto the surface 12 of the printed wiring board 11. Note that the flexible substrate 76, the spacer 74, and the microlens array 73 may be attached by the guide pins 31 after only the ceramic substrate 51 is soldered on the surface 12 of the printed wiring board 11.

  Furthermore, a procedure for connecting the optical module 41 with the guide pins 31 mounted on the printed wiring board 11 and the MT ferrule 24 will be described. Here, the MT ferrule 24 integrated with the multi-core optical fiber 26 is used. Further, the MT ferrule 24 is sandwiched between the support arms 25 of the ferrule holder 27 in advance. The exposed surface 23 of the optical fiber tip of the MT ferrule 24 is disposed to face the distal end surface 43 of the optical module 41, and the protruding end of the guide pin 31 is inserted into the ferrule side guide pin hole 22. The distal end side of the MT ferrule 24 is disposed between the support arms 25 so that the MT ferrule 24 is brought closer to the optical module 41 side, and the optical fiber distal end exposed surface 23 of the MT ferrule 24 and the distal end surface 43 of the optical module 41 are disposed. And try to hit. Then, at this time, the flanges 33 provided on the pair of support arms 25 engage with the locked protrusions 60, and the optical module 41 is fixed in a locked state. In this state, the coil spring 29 always presses the MT ferrule 24 toward the optical module 41, and the MT ferrule 24 and the optical module 41 are securely coupled.

  Therefore, according to the present embodiment, the following effects can be obtained.

  (1) In this embodiment, since the push-on fastening method is adopted for mechanical coupling between the MT ferrule 24 and the optical module 41, it is not necessary to provide a housing structure part in a part of the module body, and the optical module It is easy to achieve a reduction in height and size of 41. Further, in the present embodiment, since the arrangement mode in which the optical fiber tip exposed surface 23 of the MT ferrule 42 and the tip surface 43 of the module main body 42 are abutted is adopted, the dimension in the Z-axis direction when the two are coupled is ensured. Can be suppressed.

  (2) When the MT ferrule 24 and the module main body 42 are mechanically coupled by inserting the guide pin 31, the optical axis of the multi-core optical fiber 26 and the optical axis of the optical element such as the VCSEL 81 are aligned. It is done. For this reason, although it is a comparatively simple method, the multi-core optical fiber 26 and the optical element can be optically coupled with high efficiency.

  (3) In the present embodiment, a locked projection 60 to which the flange 33 of the ferrule holder 27 can be engaged and disengaged is provided on the second side end face 54 of the module main body 42. Therefore, for example, a sufficient margin can be easily provided between the outer surface of the module main body 42 and the internal structure as compared with the case where a concave locked portion is formed.

  (4) In this embodiment, the module body 42 is provided with a semiconductor integrated circuit element for driving an optical element or for amplifying an optical signal in addition to the optical element. Therefore, the conduction distance can be shortened and the operation speed is increased.

  (5) In this embodiment, the optical elements such as the VCSEL 81 and the semiconductor integrated circuit elements such as the driver IC 82 are provided so as not to be exposed from the outer surface of the optical module 41. In other words, the optical element and the semiconductor integrated circuit element are embedded in the optical module 41. Therefore, as compared with the configuration in which the optical element and the semiconductor integrated circuit element are exposed on the outer surface of the optical module 41, the optical element and the semiconductor integrated circuit element can be surely protected, and the reliability can be improved.

(6) In this embodiment, since the optical module 41 is provided with not only optical elements but also semiconductor integrated circuit elements, the total amount of heat generated is large. In addition, since the optical element and the semiconductor integrated circuit element are embedded in the optical module 41, the structure is such that heat tends to accumulate in the first place. However, since the optical module 41 is mainly composed of the ceramic substrate 51 excellent in heat dissipation and the lid 72 is provided, heat is efficiently dissipated to the outside. In addition, since some of the solder bumps 75 are heat dissipation solder bumps, heat is efficiently dissipated outside the optical module 41 through them.
[Second Embodiment]

  Next, the optical module 141 according to the second embodiment will be described in detail with reference to FIGS. FIG. 8 is a plan view of the optical module 141 of the present embodiment. 9 is a cross-sectional view taken along the line CC of FIG. Here, the description will focus on the parts that are different from the first embodiment, and the common parts will not be described in place of the same member numbers.

  As shown in FIGS. 8 and 9, in this optical module 141, the flexible substrate 76 that is a support for the VCSEL 81 and the driver IC 82 is omitted, and the VCSEL 81 and the driver IC 82 are directly bonded to the ceramic substrate 51. More specifically, the driver IC 82 is bonded to the bottom surface of the cavity 59 on the upper end surface 55 side of the ceramic substrate 51, and the VCSEL 81 is bonded to the first side end surface 53 of the ceramic substrate 51. The driver IC 82 is electrically connected to the through-hole conductor 58 or the conductor layer 57. The VCSEL 81 is electrically connected to the conductor layer 57 via a bonding wire 91, for example.

And even if it is the optical module 141 of the said structure, there exists an effect similar to 1st Embodiment fundamentally. Moreover, with this structure, the number of components is reduced due to the omission of the flexible substrate 76, and it is easy to achieve cost reduction. In addition, since the thermal conductivity between the ceramic substrate 51 and the lid 72 is improved, further improvement in heat dissipation can be expected.
[Third Embodiment]

  Next, the optical module 241 according to the third embodiment will be described in detail with reference to FIGS. FIG. 10 is a plan view of the optical module 241 of the present embodiment. 11 is a cross-sectional view taken along the line DD of FIG. Here, the description will focus on the parts that are different from the first embodiment, and the common parts will not be described in place of the same member numbers.

  As shown in FIGS. 10 and 11, in this optical module 241 as well, the flexible substrate 76 that was a support for the VCSEL 81 and the driver IC 82 is omitted, and the VCSEL 81 and the driver IC 82 are directly bonded to the ceramic substrate 51. More specifically, the driver IC 82 is bonded to the bottom surface of the cavity 59 on the upper end surface 55 side of the ceramic substrate 51. Further, the VCSEL 81 is bonded to the upper surface of the thin overhanging portion 244 in the ceramic substrate 51. The driver IC 82 and the VCSEL 81 are electrically connected to the through-hole conductor 58 or the conductor layer 57. In other words, in the present embodiment, the VCSEL 81 faces the Z-axis direction (upward direction in FIG. 11) instead of the X-axis direction.

A spacer 245 having a substantially L-shaped cross section is provided in the space above the thin overhanging portion 244, and a microlens array 247 with a 45 ° optical path conversion mirror 246 is provided on the spacer 245. A guide pin hole 251 is formed in the microlens array 247 along the Z-axis direction. Similarly, a guide pin hole 252 is formed in the thin overhanging portion 244 of the ceramic substrate 51. The guide pins 31 are inserted into the guide pin holes 251 and 252 so that the optical axes of the VCSEL 81 and the microlens array 247 are aligned.
According to the present embodiment, it is possible to provide an optical module 241 that can easily achieve a reduction in height and size as a whole and can be optically coupled to the multi-core optical fiber 26 with high efficiency. Moreover, with this structure, the driver IC 82 and the VCSEL 81 need only be mounted in the same direction, so that component mounting can be performed efficiently and easily. Further, since the thermal conductivity between the ceramic substrate 51 and the lid 72 is improved by omitting the flexible substrate 76, further improvement in heat dissipation can be expected.
[Fourth Embodiment]

  Next, the optical module 261 of the fourth embodiment will be described in detail with reference to FIG. FIG. 12 is a plan view of the optical module 261 of the present embodiment. Here, the description will focus on the parts that are different from the first embodiment, and the common parts will not be described in place of the same member numbers.

  As shown in FIG. 12, this optical module 261 is a so-called transmission / reception optical module, and thus includes two different types of optical elements, specifically, one VCSEL 81 and one photodiode 271. . Therefore, the optical module 261 includes not only the driver IC 82 but also the receiver IC 272 (semiconductor integrated circuit element for optical signal amplification). The driver IC 82 and the VCSEL 81 are electrically connected via the wiring pattern of the flexible substrate 76. The receiver IC 272 and the photodiode 271 are also electrically connected via another wiring pattern on the flexible substrate 76. On the upper end surface 55 side of the ceramic substrate 51, a cavity 59 for disposing the driver IC 82 and a cavity 59 for disposing the receiver IC 272 are separately formed. A conductor plating layer is formed on the inner surfaces of these cavities 59. The cavities 59 are separated from each other by a partition wall 273. With these configurations, the driver IC 82 that is the configuration on the transmission side and the receiver IC 272 that is the configuration on the reception side are electromagnetically separated. A shield member 262 is provided between the VCSEL 81 and the photodiode 271. The shield member 262 is conductor-plated on the surface of the substrate. The VCSEL 81 that is the configuration on the transmission side and the photodiode 271 that is the configuration on the reception side are electromagnetically separated by the intervention of the shield member 262. The shield member 262 may be formed by conducting conductor plating on the surface of the spacer 74.

According to the present embodiment, it is easy to achieve a low profile and a small size as a whole, and provide an optical module 261 that can be optically coupled to the multi-core optical fiber 26 with high efficiency and has high added value. Can do.
[Fifth Embodiment]

  Next, the optical module 341 of the fifth embodiment will be described in detail with reference to FIG. FIG. 13 is an exploded perspective view showing the optical module 341, the guide pin 31, the ferrule holder 27, and the MT ferrule 24 of the present embodiment (however, the cover 36 is not shown). Here, the description will focus on the parts that are different from the first embodiment, and the common parts will not be described in place of the same member numbers.

As shown in FIG. 13, in this optical module 341, the shape and the formation position of the locked portion are different from those of the first embodiment and the like. That is, in the present embodiment, for the convenience of engaging the flange portion 33 with the rear end surface 44 of the module main body 42, locked recesses 342 that are locked portions are integrally formed at two locations on the rear end surface 44. . And the collar part 33 which a pair of support arm 25 has can be engaged / disengaged with respect to these to-be-latched hollows 342. That is, even with the configuration of the present embodiment, the optical module 341 and the MT ferrule 24 can be detachably coupled by a push-on fastening method.
[Sixth Embodiment]

  Next, the optical module 441 of the sixth embodiment will be described in detail with reference to FIG. FIG. 14 is an exploded perspective view showing the optical module 441, the guide pin 31, the ferrule holder 27, and the MT ferrule 24 of this embodiment (however, the cover 36 is not shown). Here, the description will focus on the parts that are different from the first embodiment, and the common parts will not be described in place of the same member numbers.

As shown in FIG. 14, in this embodiment, the hook 33 is engaged with the rear end surface 44 of the module main body 42, but the module main body 42 is not particularly formed with a locked portion. . Even with such a configuration, the optical module 441 and the MT ferrule 24 can be detachably coupled by a push-on fastening method.
[Seventh Embodiment]

  Next, the optical module 541 of the seventh embodiment will be described in detail with reference to FIG. FIG. 15 is an exploded perspective view showing the optical module 541, the guide pin 31, the ferrule holder 27, and the MT ferrule 24 of the present embodiment (however, the cover 36 is not shown). Here, the description will focus on the parts that are different from the first embodiment, and the common parts will not be described in place of the same member numbers.

  As shown in FIG. 15, in this optical module 541, the position where the locked portion is formed is the second side end surface 54 of the module main body 42 as in the first embodiment, but the shape of the locked portion is the first. Different from one embodiment. More specifically, a pair of locked recesses 542 to which the hook portion 33 of the locking portion 25 can be engaged and disengaged are integrally formed on the second side end surface 54. Even with such a configuration, the optical module 541 and the MT ferrule 24 can be detachably coupled by a push-on fastening method.

  It goes without saying that the present invention is not limited to the above-described embodiment, and can be appropriately modified and applied without departing from the scope of the invention.

  For example, the spacers 74 and 245 used in the first to third embodiments may be omitted, and in this case, the number of parts can be further reduced.

  In the third embodiment, the ceramic substrate 51, the microlens array 247, and the lid 72 are aligned and fixed by the guide pins 31. However, the ceramic substrate 51, the microlens array 247, and the lid 72 are aligned and fixed by bonding or the like without using the guide pins 31. Also good.

  -In 1st-4th embodiment, although the lid 72 was provided only in the upper end surface of the module main body 42, you may make it provide this in several surfaces.

  -In 1st-4th embodiment, although the unevenness | corrugation did not exist especially in the inner wall face of the filling recessed part 61, and the internal diameter was substantially constant, you may provide an unevenness | corrugation by changing an internal diameter with a depth position. According to this configuration, the contact area between the inner wall surface of the filling recess 61 and the filler 63 is increased, and the adhesion of the filler 63 is improved. Therefore, the generation of gaps and cracks due to thermal stress concentration can be avoided, and the reliability is excellent.

  In the first embodiment, in forming the precision processed hole 62, filling of the filler 63 → semi-curing of the filler 63 (120 ° C.) → hole processing → surface polishing → main curing of the filler 63 (150 ° C.) Although the process is adopted, it is needless to say that another process may be adopted. For example, a process of filling the filler 63 → semi-curing of the filler 63 (120 ° C.) → surface polishing → main curing of the filler 63 (150 ° C.) → hole processing may be used.

  In the first embodiment, etc., in order to prevent the MT ferrule from detaching from the ferrule holder 27, a structure in which the cover 36 is provided on the ferrule holder 27 is adopted. It may be adopted. For example, a guide groove or a guide protrusion extending along the X-axis direction is provided inside the ferrule holder 27. On the other hand, on the outer side of the MT ferrule 24, a guided ridge or guided groove is provided that engages with the guide groove or the guide ridge and extends along the X-axis direction. Even with such a structure, the MT ferrule 24 can be prevented from detaching from the ferrule holder 27 while allowing the MT ferrule 24 to slide in the X-axis direction.

  Next, the technical ideas grasped by the embodiment described above are listed below.

  (1) A ferrule support for an optical fiber connector and a guide pin for an optical fiber connector having a locking portion in a state where the exposed end surface of the optical fiber in the ferrule and the front end surface of the ferrule are abutted against the ferrule for the optical fiber connector. A module main body that can be coupled using a light guide, and an optical element that is provided in the module main body and that is optically aligned when the plug and the module main body are coupled by insertion of the guide pin. Optical module.

  (2) A ferrule for an optical fiber connector can be coupled by a push-on fastening method using a ferrule support for an optical fiber connector having an engaging portion and a guide pin for an optical fiber connector, and a guide pin is attached to a side end surface. A module main body having a hole formed therein; and an optical element that is provided in the module main body and has an optical axis aligned when the ferrule and the module main body are coupled by insertion of the guide pin. An optical module with a guide pin, wherein the guide pin is inserted and fixed to a portion of the guide pin and protrudes from the module body.

  (3) A module main body that can be coupled to the optical fiber connector ferrule by a push-on fastening method using an optical fiber connector ferrule support having an engaging portion and an optical fiber connector guide pin; A light emitting element that is optically aligned when the ferrule and the module main body are coupled by insertion of the guide pin, and is provided in the module main body, and the ferrule and the module main body are provided by insertion of the guide pin. An optical module comprising: a light receiving element that is optically aligned when coupled.

  (4) A ceramic substrate used for an optical module that can be coupled to an optical fiber connector ferrule by a push-on fastening method using an optical fiber connector ferrule support having an engaging portion and an optical fiber connector guide pin. And a substrate main surface and a plurality of side end surfaces perpendicular to the substrate main surface, and a filling recess is formed in one of the plurality of side end surfaces, and the substrate material is formed in the filling recess. A filler made of a material having better workability is filled, a precision machining hole constituting at least a part of the guide pin hole is formed in the filler, and the engagement is provided on the side end surface other than the side end surface having the filling recess. A ceramic substrate for an optical module, characterized in that a locked portion is provided in which the locking portion can be engaged and disengaged.

The schematic front view which shows the state which mounted the optical module of 1st Embodiment which actualized this invention on the printed wiring board, and connected MT ferrule using the ferrule holder. The schematic plan view which shows the state which connected the optical module to MT ferrule using the ferrule holder. The disassembled perspective view which shows an optical module, a guide pin, a ferrule holder, and MT ferrule. The perspective view which shows the ceramic substrate for optical modules which comprises a module main body. The top view of the optical module of 1st Embodiment. Sectional drawing in the AA of FIG. Sectional drawing in the BB line of FIG. The top view of the optical module of 2nd Embodiment. Sectional drawing in the CC line | wire of FIG. The top view of the optical module of 3rd Embodiment. Sectional drawing in the DD line | wire of FIG. The top view of the optical module of 4th Embodiment. The disassembled perspective view which shows the optical module, guide pin, ferrule holder, and MT ferrule of 5th Embodiment. The disassembled perspective view which shows the optical module, guide pin, ferrule holder, and MT ferrule of 6th Embodiment. The disassembled perspective view which shows the optical module, guide pin, ferrule holder, and MT ferrule of 7th Embodiment.

Explanation of symbols

24 ... MT ferrule as a ferrule for optical fiber connector 27 ... Ferrule holder as a support for optical fiber connector 31 ... Guide pin for optical fiber connector 33 ... Gutter 41, 141, 241, 261, 341 as a locking part 441, 541 ... optical module 42 ... module body 43 ... tip surface (of optical module) 51 ... ceramic substrate for optical module 53 ... first side end surface 54 ... second side end surface 55 as support body contact surface 55 ... as substrate main surface Upper end surface 60: Locked protrusion 61 as a locked portion 61 ... Filling recess 62 ... Precisely processed hole 63 ... Filler 72 ... Lid as metal body 75 ... Solder bump as electrical connection terminal 80 ... As guide pin hole Module body side guide pin hole 81... VCSEL as optical element
82 ... Driver IC as a semiconductor integrated circuit element for driving an optical element
271: Photodiode as an optical element 272: Receiver IC as a semiconductor integrated circuit element for optical signal amplification

Claims (10)

Using a ferrule support for an optical fiber connector having a locking portion and a guide pin for an optical fiber connector, an optical fiber connector ferrule, a module main body that can be coupled by a push-on fastening method,
An optical module comprising: an optical element provided on the module main body, the optical element being optically aligned when the ferrule and the module main body are coupled by insertion of the guide pin.   The module main body includes a front end surface and a ferrule support contact surface that can be contacted with a part of the ferrule support and is perpendicular to the front end surface. A guide pin hole into which a pin can be inserted is formed as an opening, and a locking portion to which the locking portion of the ferrule support is detachable is provided on the ferrule support contact surface. The optical module according to claim 1.   3. The optical module according to claim 1, wherein the module body is mainly composed of a material having a higher heat dissipation property than a resin material used for an optical fiber connector.   The optical module according to claim 3, wherein the module body is mainly composed of a ceramic substrate.   A filling recess is formed in the first side end surface perpendicular to the substrate main surface of the ceramic substrate, and the filling recess is filled with a filler made of a material having better workability than the ceramic substrate, 5. The optical module according to claim 4, wherein the filler is formed with a precision processing hole that constitutes at least a part of the guide pin hole.   6. The module main body is provided with at least one of a semiconductor integrated circuit element for driving optical elements and a semiconductor integrated circuit element for amplifying optical signals. The optical module according to item.   The optical module according to claim 6, wherein the optical element is disposed on the side end surface side of the ceramic substrate, and the semiconductor integrated circuit element is disposed on the substrate main surface side of the ceramic substrate.   8. The optical module according to claim 2, wherein a metal body is provided on a surface other than the front end surface and the rear end surface in the module main body. 9.   The optical module according to claim 2, wherein the module body is provided with a plurality of electrical connection terminals.   A ceramic substrate used for an optical module that can be coupled to a ferrule for an optical fiber connector by a push-on fastening method using a ferrule support for an optical fiber connector having a locking portion and a guide pin for an optical fiber connector. A ceramic substrate for an optical module, wherein a locked portion to which the ferrule locking portion can be engaged and disengaged is provided.

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