Abstract:
An optical connector comprising a housing ( 11 ) including a bottom wall, a plurality of side walls each of which stands from the bottom wall, and an opening defined by the side walls; a metal lead ( 21 ) mounted on the bottom wall; a photoelectric conversion element ( 23 ) mounted on the metal lead ( 21 ); a resin case ( 26 ) covering the photoelectric conversion element ( 23 ); a lens ( 25 ) corresponding to the photoelectric conversion element ( 23 ) and provided on the resin case ( 26 ); and an electromagnetic shield ( 12 ) provided on the resin case ( 26 ) and including a first through hole ( 12   e ) from which the lens ( 25 ) is exposed.

Description:
TECHNICAL FIELD 
     The present invention relates to a female optical connector of the field of optical communication, and especially to the female optical connector into which a male optical connector with an optical cable attached thereto is detachably inserted. Also, the present invention relates to a method of manufacturing the female optical connector. 
     BACKGROUND ART 
     In the field of optical communication, optical information which is obtained by photo-electrically converting large volumes of digital information is transmitted by optical cables at high speed. In this technology field, it is possible to hook up a plurality of electrical apparatuses with optical cables by connecting a male optical connector to a female optical connector. The male optical connector has a plug housing to which a optical cable is attached, and the female optical connector has a receptacle housing inside of which at least one photoelectric conversion element of a light-emitting element and a light-receiving element. 
     In the case where the light-emitting element is mounted in the photoelectric conversion element module inside the female optical connector, optical information emergent from the light-emitting element is transmitted to the optical cable side through the male optical connector. Meanwhile, in the case where the light-receiving element is mounted in the photoelectric conversion element module inside the female optical connector, optical information transmitted from the optical cable side is received by the light-receiving element through the male optical connector. In the case where the light-emitting element and the light-receiving element are mounted in the photoelectric conversion element module inside the female optical connector, optical information is transmitted and received. 
     As a female optical connector into which a male optical connector with an optical cable attached thereto is detachably inserted, there is an optical connector with improvements with respect to both electromagnetic noise shielding performance and radiation performance. (e.g., see JP-A-2002-303766). 
       FIG. 10  is an exploded perspective view of a related optical connector, and  FIG. 11  is a vertical cross-sectional view of the related optical connector. 
     A related optical connector  100  shown in  FIGS. 10 and 11  is disclosed in the aforementioned JP-A-2002-303766, and a brief description will be given with reference to JP-A-2002-303766. 
     As shown in  FIGS. 10 and 11 , the related optical connector  100  includes a photoelectric conversion element module  101 , a metal shield case  110 , a connector housing  120 , and a metal shield cover  130 . 
     Here, a description will be given for the aforementioned members  101 ,  110 ,  120 , and  130  in this order. The photoelectric conversion element module  101  has a photoelectric conversion element  103  mounted in front of an element body portion  102  and a plurality of lead terminals  104  extending below the element body portion  102 . 
     The metal shield case  110  is formed into a rectangular shape by using a metal plate for shielding electromagnetic noise by covering the photoelectric conversion element module  101 . Further, the metal shield case  110  has a pin-like soldering portion  110   a  extending downward from the underside thereof. 
     The connector housing  120  is formed into a substantially rectangular shape by using an insulative resin material, and has on its front side an opening  120   a  into which a mating connector (not shown) is detachably inserted. A ferrule guiding portion  120   b , into which a ferrule fitted to a leading end of an optical cable in the mating connector (not shown) is guided, is formed in the rear of the interior of this opening  120   a  (shown only in  FIG. 11 ) in an annular shape in conformity with the photoelectric conversion element  103  of the photoelectric conversion element module  101 . Further, a recess  120   c  for accommodating the metal shield case  110  which covers the photoelectric conversion element module  101  is formed in the rear of this ferrule guiding portion  120   b , and a positioning fixing portion  120   d  extends downward from the underside of the connector housing  120 . 
     In addition, the metal shield cover  130  is formed into a box shape with its front and lower sides open by using a metal plate, and has a plurality of pin-like soldering portions  130   a  extending downward from the underside of the metal shield cover  130 . The metal shield cover  130  is in contact with the rear side portion of the metal shield case  110  which is exposed to outside the connector housing  120 , and the metal shield cover  130  shields electromagnetic noise by covering the outer sides of the connector housing  120 , and radiates heat generated in the photoelectric conversion element  103  to the outside through the metal shield case  110 . 
     Further, after the photoelectric conversion element module  101  is covered by the metal shield case  110 , this metal shield case  110  is accommodated into the recess  120   c  from the rear side of the connector housing  120 . After the connector housing  120  is covered by the metal shield cover  130 , the optical connector  100  is mounted on a mounting board P, the soldering portion  110   a  of the metal shield case  110  and the soldering portions  130   a  of the metal shield cover  130  are soldered on the back side of the mounting board P. 
     It is described in the JP-A-2002-303766 that, according to the above-described related optical connector  100  of above configuration, the photoelectric conversion element module  101  is shielded from electromagnetic noise doubly by both the metal shield case  110  and the metal shield cover  130 , and the heat generated in the photoelectric conversion element  103  is radiated to the outside through the metal shield case  110 . 
     Citation List 
     Patent Literature
         PLT1: JP-A-2002-303766
 
Summary Of Invention
 
Technical Problem
       

     With the above-described related optical connector  100 , the photoelectric conversion element module  101 , the metal shield case  110 , the connector housing  120 , and the metal shield cover  130  are respectively fabricated separately, and these component members  101 ,  110 ,  120 , and  130  are assembled, so that the assembling man-hours disadvantageously increases. Hence, the related optical connector  100  has been expensive. 
     In addition, with the above-described related optical connector  100 , although the photoelectric conversion element module  101  can be reliably shielded from electromagnetic noise by both the metal shield case  110  and the metal shield cover  130 , the both members  110  and  130  require sheet metal bending in conformity with the outer configurations of the photoelectric conversion element module  101  and the connector housing  120 . Hence, a problem also arises in that the manufacturing cost of the both members  110  and  130  disadvantageously becomes high. 
     Accordingly, an object of the invention is to provide a female optical connector and a method of manufacturing a female optical connector which are capable of shielding the photoelectric conversion element module from electromagnetic noise by a simple structure and of improving production efficiency by reducing the assembling manhour. 
     Solution to Problem 
     According to one or more illustrative aspects of the present invention, there is provided an optical connector comprising a housing including a bottom wall, a plurality of side walls each of which stands from the bottom wall, and an opening defined by the side walls; a metal lead provided on the bottom wall; a photoelectric conversion element mounted on the metal lead; a resin case covering the photoelectric conversion element; a lens corresponding to the photoelectric conversion element and provided on the resin case; and an electromagnetic shield provided on the resin case and including a first through hole from which the lens is exposed. 
     Preferably, the housing includes a partition wall which is parallel to the bottom wall and has a second through hole corresponding to the first through hole. 
     Preferably, the electromagnetic shield is sandwiched by the resin case and the partition wall. 
     Preferably, the lens and resin case are integrally formed from a translucent resin. 
     Preferably, the photoelectric conversion element is at least one of a light-emitting element and a light-receiving element. 
     Preferably, an optical axis of the photoelectric conversion element and an optical axis of the lens are identical. 
     Preferably, the first through hole and the second through hole have a same shape. 
     In addition, according to one or more illustrative aspects of the invention, there is provided a method for manufacturing an optical connector comprising steps of: mounting a photoelectric conversion element on a metal lead frame; obtaining a photoelectric conversion module by molding a resin case for covering the photoelectric conversion element and a lens having an optical axis which is identical to an optical axis of the photoelectric conversion element from a translucent resin; mounting an electromagnetic shield on the resin case; forming a resin housing so as to bury the photoelectric conversion module therein. 
     Preferably, the photoelectric conversion element is at least one of a light-emitting element and a light-receiving element. 
     Advantageous Effects of Invention 
     According to the female optical connector and the method of manufacturing a female optical connector in accordance with the invention, since the photoelectric conversion element module is embedded on the rear side of the interior of the opening of the receptacle housing in the state in which the electromagnetic shield cover is superposed on the front side of the resin casing, the photoelectric conversion element can be reliably shielded from electromagnetic noise by the electromagnetic shield cover having a simple structure. In addition, the female optical connector with the photoelectric conversion element module embedded in the receptacle housing can be mounted as it is on a printed wiring board, for example. Therefore, it is possible to substantially reduce the assembling manhour of the female optical connector, thereby making it possible to contribute to the improvement of productivity. 
     Furthermore, since the lens having, for example, a convex surface is disposed in front of the photoelectric conversion element with its optical axis aligned with that of the photoelectric conversion element, it is possible to reliably effect at least one of transmission and reception of optical information. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a perspective view illustrating a female optical connector in accordance with the invention and a mating male optical connector. 
         FIGS. 2A to 2C  are a horizontal cross-sectional view, a front elevational View, and a vertical cross-sectional view illustrating the female optical connector in accordance with the invention. 
         FIGS. 3A and 3B  are perspective views illustrating a first step for mounting photoelectric conversion elements and driving ICs on each metal lead frame through a wiring board. 
         FIG. 4  is a perspective view illustrating a second step in which lenses disposed on front sides of the photoelectric conversion elements with their optical axes aligned with those of the photoelectric conversion elements as well as resin cases for protecting the photoelectric conversion elements and the element driving ICs are primarily molded from a transparent resin material. 
         FIG. 5  is a perspective view of a third step in which after the lenses and each resin case are primarily molded from the transparent resin material, a plurality of lead terminals formed on the other inner side surface of each outer frame portion are cut off from each outer frame portion and are subjected to bending. 
         FIG. 6  is a perspective view illustrating a fourth step for forming electromagnetic shield covers. 
         FIG. 7  is a fifth step for superposing each electromagnetic shield cover on the front side of the resin case of each photoelectric conversion element module. 
         FIG. 8  is a vertical cross-sectional view illustrating in enlarged form a state in which the electromagnetic shield cover is superposed on the front side of the resin case of the photoelectric conversion element module. 
         FIG. 9  is a perspective view illustrating a sixth step in which the female optical connector is secondarily molded from a transparent resin material. 
         FIG. 10  is an exploded perspective view illustrating a related optical connector. 
         FIG. 11  is a vertical cross-sectional view of the related optical connector. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     Referring now to  FIGS. 1 to 9 , a detailed description will be given of an embodiment of a female optical connector and a method of manufacturing a female optical connector in accordance with the invention. 
     Example 1 
       FIG. 1  is a perspective view illustrating a female optical connector in accordance with the invention and a mating male optical connector, and  FIGS. 2A to 2C  are a horizontal cross-sectional view, a front elevational view, and a vertical cross-sectional view illustrating the female optical connector in accordance with the invention. 
     As shown in  FIG. 1 , a female optical connector  10  in accordance with the invention is so configured as to be capable of effecting optical communication of large volumes of optical information among various electronic equipment via an optical cable  3  by being connected to a male optical connector  1  having a plug housing  2  with the optical cable  3  attached thereto. 
     With the above-described female optical connector  10  in accordance with the invention, an opening  11   a  having a rectangular shape is open on the front side of a receptacle housing  11  made of a resin and formed into the shape of a substantially rectangular parallelepiped, and the plug housing  2  of the mating male optical connector  1  is capable of being detachably inserted into this opening  11   a  in the direction of arrows. 
     At this juncture, the plug housing  2  of the male optical connector  1  is resin molded into a slightly smaller shape than the outer shape of the receptacle housing  11  in conformity with the shape of the opening  11   a  of the receptacle housing  11  of the female optical connector  10 . 
     In addition, in the female optical connector  10 , a guide portion  11   b  with a repetitive recessed and projecting pattern is formed on one inner side surface of the opening  11   a  of the receptacle housing  11 , and a guide portion  2   a  with a recessed and projecting pattern is correspondingly formed on one outer side surface of the plug housing  2  of the male optical connector  1 . The both guide portions  11   b  and  2   a  are formed by maintaining a complementary relation such that, when the guide portions  11   b  and  2   a  are opposed to each other, a recessed portion on one side is fitted to a projecting portion on the other side, and a projecting portion on one side is fitted to a recessed portion on the other side. Thus, a measure is provided for preventing erroneous insertion when the top and the bottom or the left and the right of the male optical connector  1  are inverted with respect to the female optical connector  10 . 
     In addition, the female optical connector  10  in accordance with the invention is mounted on a printed wiring board P in a state in which an electromagnetic shield cover  12  and a photoelectric conversion element module  20  having at least one photoelectric conversion element  23  of a light-emitting element and a light-receiving element are embedded in a rear portion of the interior of the opening  11   a  of the receptacle housing  11 . 
     In this embodiment, since a light-emitting element  23 A and a light-receiving element  23 B are incorporated in the photoelectric conversion element module  20  as the photoelectric conversion elements  23 , transmission and reception are possible respectively independently via the two optical cables  3  attached to the male optical connector  1 . 
     It should be noted that the above-described photoelectric conversion element module  20  is also called a fiber optic transceiver (FOT). 
     Here, a specific description will be given of the above-described female optical connector  10  in accordance with the invention with reference to  FIGS. 2A to 2C . 
     First, in the photoelectric conversion element module  20  which is embedded in the female optical connector  10 , the photoelectric conversion elements  23  ( 23 A and  23 B) and element driving ICs  24  ( 24 A and  24 B) are respectively mounted on an electrically conductive metal lead frame  21  in a wire-bonded state. Further, a plurality of lead terminals  21   c  respectively extending from one side surface of the metal lead frame  21  and a plurality of lead terminals  21   d  extending from the opposite side surface opposing the one side surface of the metal lead frame  21  are adapted to be soldered to the printed wiring board P. 
     At this juncture, the photoelectric conversion element module  20  is sufficient if it has at least one photoelectric conversion element  23  of the light-emitting element and the light-receiving element. In this embodiment, however, the photoelectric conversion element module  20  has the light-emitting element  23 A and the light-receiving element  2313  juxtaposed side by side in a close proximity to each other with a predetermined interval provided therebetween in the left-right direction. In conjunction with this, the light-emitting element driving IC  24 A and the light-receiving element driving IC  24 B are respectively provided side by side with the left and right outer sides of the elements  23 A and  23 B. 
     Further, in the case where the light-emitting element  23 A is used as the photoelectric conversion element  23 , a light emitting diode (LED), a vertical cavity surface emitting laser (VCSEL), or the like is used as this light-emitting element  23 A. Meanwhile, in the case where the light-receiving element  238  is used as the photoelectric conversion element  23 , a light emitting diode (LED), a photo diode (PD) is used as this light-receiving element  23 B. 
     In addition, the photoelectric conversion element module  20  is integrally formed as two lenses  25  and a resin case  26  for protecting the photoelectric conversion elements  23  ( 23 A and  23 B) and the element driving ICs  24  ( 24 A and  24 B) are primarily molded from a transparent resin material, as will be described later, the two lenses  25  being respectively disposed on front sides of the photoelectric conversion elements  23  ( 23 A and  23 B) in spaced-apart relation thereto with their optical axes K aligned with those of the photoelectric conversion elements  23  ( 23 A and  23 B) mounted on the metal lead frame  21 . 
     Since the two lenses  25  are formed with convex surfaces so that their foci are respectively aligned with the optical axes of the light-emitting element  23 A and the light-receiving element  23 B, the two lenses  25  are adapted to be capable of reliably effecting the transmission and reception of optical information with respect to the optical cables  3  attached to the plug housing  2  of the male optical connector  1  shown in  FIG. 1 . 
     Further, the electromagnetic shield cover  12  having two light transmitting holes  12   e  for respectively facing the two lenses  25  is superposed on the front side of the resin case  26  of the photoelectric conversion element module  20 . As an electrically conductive metal plate is used for the electromagnetic shield cover  12 , the electromagnetic shield cover  12  reliably shields the photoelectric conversion elements  23  ( 23 A and  23 B) and the element driving ICs  24  ( 24 A and  24 B) from electromagnetic noise. 
     The electromagnetic shield cover  12  is formed in a size capable of covering the front side of the resin case  26  of the photoelectric conversion element module  20 , and terminals  12   c  and  12   d  (shown in  FIG. 6 ) for soldering to the printed wiring board P extend from one and the other sides of the electromagnetic shield cover  12 . 
     Next, the receptacle housing  11  which forms the outer appearance of the female optical connector  10  in accordance with this embodiment has a partition wall  11   d  which is suspendedly provided on the rear side of the interior of the opening  11   a  which is open on the front side. The partition wall  11   d  has a pair of light transmitting holes  11   c  for respectively facing the two lenses  25 . Further, in the state in which the electromagnetic shield cover  12  is superposed on the rear side of this partition wall  11   d  on the front side of the resin case  26 , the photoelectric conversion element module  20  is embedded by secondary molding using a transparent resin material. 
     A plurality of positioning bosses  11   e  are projectingly formed on the bottom side of the receptacle housing  11 , and as these positioning bosses  11   e  are respectively inserted into a plurality of positioning holes (not shown) formed in the printed wiring board P, the female optical connector  10  is correctly positioned and mounted on the printed wiring board P. 
     According to the female optical connector  10  in accordance with the embodiment constructed as described above, since the photoelectric conversion element module  20  is embedded on the rear side of the interior of the opening  11   a  of the receptacle housing  11  in the state in which the electromagnetic shield cover  12  is superposed on the front side of the resin case  26 , the photoelectric conversion elements  23  ( 23 A and  23 B) and the element driving ICs  24  ( 24 A and  24 B) are reliably shielded from electromagnetic noise by the electromagnetic shield cover  12  having a simple structure. In addition, the female optical connector  10  with the photoelectric conversion element module  20  embedded in the receptacle housing  11  is mounted as it is on the printed wiring board P, for example. Therefore, it is possible to substantially reduce the assembling man-hours of the female optical connector  10 , thereby making it possible to contribute to the improvement of productivity. 
     Furthermore, since the lens  25  having, for example, a convex surface is disposed in front of the photoelectric conversion element  23  ( 23 A,  23 B) with its optical axis K aligned with that of the photoelectric conversion element  23  ( 23 A,  23 B), it is possible to reliably effect at least one of transmission and reception of optical information. 
     Next, referring to  FIGS. 3A to 9 , a description will be given of the method of manufacturing the female optical connector  10  in accordance with the invention in the order of steps. 
       FIGS. 3A and 3B  are perspective views illustrating a first step for mounting the photoelectric conversion elements and the driving ICs on each metal lead frame through the wiring board.  FIG. 4  is a perspective view illustrating a second step in which the lenses disposed on the front sides of the photoelectric conversion elements with their optical axes aligned with those of the photoelectric conversion elements as well as the resin casings for protecting the photoelectric conversion elements and the element driving ICs are primarily molded from a transparent resin material.  FIG. 5  is a perspective view of a third step in which after the lenses and each resin casing are primarily molded from the transparent resin material, the plurality of lead terminals formed on the other inner side surface of each outer frame portion are cut off from each outer frame portion and are subjected to bending.  FIG. 6  is a perspective view illustrating a fourth step for forming the electromagnetic shield covers.  FIG. 7  is a fifth step for superposing each electromagnetic shield cover on the front side of the resin casing of each photoelectric conversion element module.  FIG. 8  is a vertical cross-sectional view illustrating in enlarged form a state in which the electromagnetic shield cover is superposed on the front side of the resin casing of the photoelectric conversion element module.  FIG. 9  is a perspective view illustrating a sixth step in which the female optical connector is secondarily molded from a transparent resin material. 
     First, in the first step shown in  FIGS. 3A and 3B , after an electrically conductive steel plate or a brass plate serving as a first carrier C 1  is mounted on an press machine (not shown), a plurality of (e.g., four) metal lead frames  21  are simultaneously punched out in the first molding carrier C 1  by press working in such a manner as to be connected in the longitudinal direction. 
     Here, a description will be given of one of the four metal lead frames  21 . In the one metal lead frame  21 , an outer frame portion  21   a  is punched out into a rectangular frame shape, and a pair of guide-pin fitting round holes  21   b , into which a pair of guide pins provided in a die of the press machine (not shown) are respectively fitted, are penetratingly bored in upper and lower two diagonal corner portions of this outer frame portion  21   a . Further, on one inner side surface, extending along the longitudinal direction of the first molding carrier C 1 , of the outer frame portion  21   a , the plurality of lead terminals  21   c  with short lengths are formed at predetermined intervals perpendicularly to the longitudinal direction. Also, on the other inner side surface opposing the one inner side surface, the plurality of lead terminals  21   d  with large lengths are formed at predetermined intervals in such a manner as to oppose the plurality of lead terminals  21   c.    
     In addition, on the pluralities of the lead terminals  21   c  and  21   d  formed in the one metal lead frame  21 , the set of the light-emitting element  23 A and the light-emitting element driving IC  24 A and the set of the light-receiving element  2313  and the light-receiving element driving IC  24 B are mounted in a wire bonded state at a predetermined interval therebetween along the longitudinal direction of the first molding carrier C 1 . 
     Further, in this step, the respective metal lead frames  21  remain connected along the longitudinal direction without being cut along cutting lines  29  indicated by the two-dot chain lines. 
     Next, in the second step shown in  FIG. 4 , the state in which the photoelectric conversion elements  23  ( 23 A and  23 B) and the element driving ICs  24  ( 24 A and  24 B) are mounted on the respective metal lead frames  21  with the four metal lead frames  21  connected in the first molding carrier C 1  is handled as a work. This work is set in a mold of an injection molding machine (not shown), and is positioned by inserting the guide pins provided in the mold into the guide-pin fitting round holes  21   b  formed in the outer frame portion  21   a  of each metal lead frame  21   b.    
     Then, in the mold of the injection molding machine (not shown), the lenses  25  disposed on the front sides of the photoelectric conversion elements  23  ( 23 A and  23 B) with their optical axes K aligned with those of the photoelectric conversion elements  23  ( 23 A and  23 B) as well as the resin casings  26  for protecting the photoelectric conversion elements  23  ( 23 A and  23 B) and the element driving ICs  24  ( 24 A and  24 B) are primarily molded from a transparent resin material. 
     In this step as well, the respective metal lead frames  21  remain connected along the longitudinal direction without being cut along cutting lines  29  indicated by the two-dot chain lines. 
     Next, in the third step shown in  FIG. 5 , after the lenses  25  and each resin case  26  are primarily molded from the transparent resin material on the first molding carrier C 1 , the plurality of lead terminals  21   d  formed on the other inner side surface of each outer frame portion  21   a  are cut off from each outer frame portion  21   a  in the state in which the plurality of lead terminals  21   c  formed on the one inner side surface of each metal lead frame  21  remain connected to the outer frame portion  21   a . These lead terminals  21   d  are bent toward the plurality of lead terminals  21   c  formed on the one inner side surface, and then the respective leading end portions of the lead terminals  21   d  are further bent downward. 
     Accordingly, the four photoelectric conversion element modules  20  are formed simultaneously in this step, but here as well the respective metal lead frames  21  remain connected along the longitudinal direction without being cut along cutting lines  29  indicated by the two-dot chain lines. 
     Next, in the fourth step shown in  FIG. 6 , after an electrically conductive metal plate serving as a second carrier C 2  is mounted on an press machine (not shown), the plurality of (e.g., four) electromagnetic shield covers  12  are simultaneously punched out in the second molding carrier C 2  by press working in such a manner as to be connected in the longitudinal direction. 
     At this juncture, the second molding carrier C 2  for forming the four electromagnetic shield covers  12  are set with the same overall size as that of the first molding carrier C 1  since the second molding carrier C 2  is superposed on the first molding carrier C 1  with the four metal lead frames  21  formed thereon, as will be described later. 
     Here, a description will be given of one of the four electromagnetic shield covers  12 . In the one electromagnetic shield cover  12 , an outer frame portion  12   a  is punched out into a rectangular frame shape with the same shape as that of the outer frame portion  21   a  of the metal lead frame  21 , and a pair of guide-pin fitting round holes  12   b , into which the pair of guide pins provided in the die of the press machine (not shown) are respectively fitted, are penetratingly bored in upper and lower two diagonal corner portions of this outer frame portion  12   a  at the same positions as those of the guide-pin fitting round holes  21   h  formed in the metal lead frame  21 . Further, on one inner side surface, extending along the longitudinal direction of the second molding carrier C 2 , of the outer frame portion  12   a , the two lead terminals  12   c  with short lengths are formed at a predetermined interval therebetween perpendicularly to the longitudinal direction. Also, on the other inner side surface opposing the one inner side surface, the two lead terminals  12   d  with large lengths are formed at a predetermined interval therebetween in such a manner as to oppose the two terminals  12   c . Further, one electromagnetic shield cover  12  is formed in a rectangular shape between the two terminals  12   c  and the two terminals d. 
     At this juncture, one electromagnetic shield cover  12  is formed with such an overall size that the electromagnetic shield cover  12  is capable of covering the front surface of the resin casing  26  of the photoelectric conversion element module  20  obtained in  FIG. 5 , and the two light transmitting holes  12   e  for facing the two lenses  25  ( FIG. 5 ) are penetratingly formed in each electromagnetic shield cover  12 . 
     In this step as well, the respective electromagnetic shield covers  12  remain connected along the longitudinal direction without being cut along cutting lines  29  indicated by the two-dot chain lines. 
     It should be noted that the step of forming the electromagnetic shield covers  12  need not necessarily be carried out in this fourth step, and may be carried out in advance. 
     Next, in the fifth step shown in  FIG. 7 , the second molding carrier C 2  ( 12 ) with the four electromagnetic shield covers  12  formed therein is superposed on the first molding carrier C 1  ( 21 ) holding the four photoelectric conversion element modules  20  set in the mold of the injection molding machine (not shown) such that the guide pins provided in the mold (not shown) are fitted in the guide-pin fitting round holes  21   b  in the respective outer frame portions  21   a  so as to effect the positioning of the both carriers C 1  and C 2 . In this state, in the mold of the injection molding machine (not shown), each electromagnetic shield cover  12  covers the front surface of the resin case  26  of each photoelectric conversion element module  20  with the lenses  25  facing the interiors of the light transmitting holes  12   e , as also shown in  FIG. 8  in enlarged form. 
     Next, in the sixth step shown in  FIG. 9 , in the state in which the second molding carrier C 2  ( 12 ) is superposed on the first molding carrier C 1  ( 21 ) in the mold of the injection molding machine (not shown) in the fifth step, the female optical connector  10  is secondarily molded from a transparent resin material. The female optical connector  10  is thereby obtained in a state in which the electromagnetic shield cover  12  and the photoelectric conversion element module  20  are embedded therein, and the female optical connector  10  is connected to the respective outer frame portions  21   a  and  12   a  of the both molding carriers C 1  and C 2 . Subsequently, the respective outer frame portions  21   a  and  12   a  of the both molding carriers C 1  and C 2  are cut, thereby making it possible to obtain the female optical connector  10  in accordance with the invention described earlier with reference to  FIGS. 1 to 2C . 
     At this juncture, it suffices if either method is adopted between the method in which the four female optical connectors  10  are secondarily molded simultaneously and the method in which after the respective outer frame portions  21   a  and  12   a  are cut off in advance one by one from the first and second molding carriers C 1  and C 2  along the cutting lines  29 , the respective one outer frame portions  21   a  and  12   a  are superposed in the mold of the injection molding machine (not shown), and the female optical connectors  10  are secondarily molded one by one. 
     Industrial Applicability 
     According to the female optical connector and the method of manufacturing a female optical connector in accordance with the invention, it is possible to substantially reduce the assembling man hour of the female optical connector, thereby making it possible to contribute to the improvement of productivity. 
     While the present invention has been shown and described with reference to certain exemplary embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. 
     This application claims priority from Japanese Patent Application No. 2008-196284 filed on Jul. 30, 2008, the entire subject matter of which is incorporated herein by reference. 
     Reference Signs List 
     
         
           1 : male optical connector 
           2 : plug housing 
           2   a : guide portion with a recessed and projecting pattern 
           3 : optical cable 
           10 : female optical connector 
           11 : receptacle housing 
           11   a : opening 
           11   b : guide portion with a recessed and projecting pattern 
           11   c : light transmitting hole 
           11   d : partition wall 
           11   e : positioning boss 
           12 : electromagnetic shield cover 
           12   a : outer frame portion 
           12   b : guide-pin fitting round hole 
           12   c ,  12   d : terminals 
           12   e : light transmitting hole 
           21 : metal lead frame 
           21   a : outer frame portion 
           21   b : guide-pin fitting round hole 
           21   c ,  21   d : lead terminals 
           22 : wiring board 
           23 : photoelectric conversion element 
           23 A: light-emitting element 
           23 B: light-receiving element 
           24 : element driving IC 
           24 A: light-emitting element driving IC 
           24 B: light-receiving element driving IC 
           25 : lens 
           26 : resin case 
         C 1 , C 2 : first and second molding carriers 
         K: optical axis of the photoelectric conversion element 
         P: printed wiring board