JP2009236954A - Optical connector and three-dimensionally formed circuit board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical connector with an optical module capable of signal transmission at high speed and having an excellent EMC characteristic. <P>SOLUTION: The optical connector includes a receptacle and a plug as the optical module. Recessed parts 23a and 23b having a light receiving element 25a and a light emitting element 25b respectively disposed therein are formed on the upper surface of a circuit block 22 stored in a body of the plug. Recessed parts 24a and 24b having a receiving element 28a and a transmitting element 28b respectively disposed therein are formed on the lower surface of the circuit block 22. Connector headers 33a and 33b connected respectively to the receiving element 28a and the transmitting element 28b are also mounted on the lower surface of the circuit block 22. In the circuit block 22, a plurality of vias 39 extending from the upper surface to the lower surface is formed between the light receiving element 25a and the light emitting element 25b, and a conductive plating 39a is formed on the inner circumferential surface of each via 39. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an optical connector and a three-dimensional molded circuit board, and more specifically, a three-dimensional molded circuit board including a light emitting element and a light receiving element, a transmission circuit that drives the light emitting element, and a reception circuit that processes an output signal of the light reception signal; The present invention relates to an optical connector having an optical module in which an optical transmission medium is optically coupled to a light emitting element and a light receiving element of the three-dimensionally molded circuit board.

  2. Description of the Related Art Conventionally, an optical fiber is used for a data transmission path in a device that transfers data at high speed. In general, when data is transferred by an optical fiber, a light emitting element or a light receiving element is provided in a receptacle mounted on a substrate. By connecting a plug holding a ferrule to which an optical fiber is fixed to a receptacle provided with the light emitting element, light emitted from the light emitting element is introduced into the optical fiber. Further, by connecting a plug holding a ferrule to which an optical fiber is fixed to a receptacle provided with a light receiving element, the light transmitted by the optical fiber is received by the light receiving element. On the substrate on which the receptacle is mounted, a transmission circuit that drives the light emitting element and a reception circuit that performs signal processing such as amplification and waveform shaping on a signal output from the light receiving element are formed.

  However, as described above, in the method of connecting the optical fiber and the light receiving element or the light emitting element by connecting the plug holding the ferrule and the receptacle, the dust adhering to the end surface of the ferrule, the cover member covering the light emitting element or the light receiving element It is necessary to wipe off etc. and is not easy to use. In the assembly process, it is necessary to prepare a work environment such as reducing dust.

For this reason, a method has been proposed in which a light receiving element or a light emitting element and an electrical connector are mounted on a fixing member to which an optical fiber is fixed, and this electrical connector is connected to an electrical connector of a receptacle implemented on a substrate (for example, Patent Document 1). By connecting the electrical connectors to each other, handling of the plug and the receptacle is facilitated, and assembly can be performed even in an operation process of connecting with an electrical cable.
JP 2006-215348 A

  By the way, in order to transmit and receive data, a receptacle provided with a light receiving element and a receptacle provided with a light emitting element are necessary. For this reason, a light emitting element and a light receiving element are provided in one receptacle. Since the signal supplied from the transmitting circuit to the light emitting element and the signal supplied from the light receiving element to the receiving circuit are both high frequency signals, high frequency noise may be generated from the circuit and the electric signal transmission path. Further, since the signal output from the light receiving element to the receiving circuit is very weak (the amplitude is extremely small compared to the amplitude of the signal when transmitted), it is easily affected by noise entering from the outside. Therefore, when a light emitting element and a light receiving element are provided in one receptacle, there is a possibility that crosstalk occurs due to interference of noise generated in a signal transmitted to a received signal.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to be used for an optical connector having an optical module capable of transmitting signals at high speed and having excellent EMC characteristics, and an optical module. The object is to provide a three-dimensional molded circuit board.

  To achieve the above object, an invention according to claim 1 is an optical connector having a receptacle and an optical module connected to the receptacle, and the optical module holds a plurality of ferrules having an optical transmission medium. And a three-dimensionally shaped circuit board accommodated in the accommodating recess, the three-dimensionally shaped circuit board having a light receiving element on a first surface facing the tip of the ferrule. An optical element disposing recess in which a light emitting element is disposed, an electric element disposing recess in which a receiving element and a transmitting element are disposed on a second surface different from the first surface, and the light receiving element And the wiring for electrically connecting the receiving element, the wiring for electrically connecting the light emitting element and the transmitting element, and the receiving element attached to a surface excluding the first surface. And A connector header that is connected to each of the transmitting elements and connected to a connector socket of the receptacle, and extends from the first surface toward the second surface between the light receiving element and the light emitting element. And a shield portion.

  According to this configuration, the shield portion formed between the light receiving element and the light emitting element is generated by a signal transmitted from the transmitting element to the light emitting element with respect to a signal transmitted from the light receiving element to the receiving element. Reduce the effect of noise. Accordingly, it is possible to transmit signals between the light receiving element and the receiving element and between the transmitting element and the light emitting element at high speed, and it is possible to provide an optical connector having excellent EMC characteristics.

  According to a second aspect of the present invention, in the optical connector according to the first aspect, the three-dimensional molded circuit board has a shield pattern that covers the surface. According to this configuration, the shield pattern reduces the influence of external noise of the three-dimensional molded circuit board on the signal transmitted from the light receiving element to the receiving element and the signal transmitted from the transmitting element to the light emitting element. . Further, noise generated by the signal transmitted from the light receiving element to the receiving element and the signal transmitted from the transmitting element to the light emitting element is prevented from being radiated to the outside of the three-dimensional molded circuit board. Therefore, it is possible to provide an optical connector that can transmit signals at high speed and has excellent EMC characteristics.

  According to a third aspect of the present invention, in the optical connector according to the first or second aspect, the three-dimensional molded circuit board is provided between the light receiving element and the receiving element, and between the light emitting element and the transmitting element. It has a ground layer formed between them. According to this configuration, since the noise propagating between the light receiving element and the receiving element and between the light emitting element and the transmitting element is suppressed, an optical connector having excellent EMC characteristics can be provided.

  According to a fourth aspect of the present invention, in the optical connector according to any one of the first to third aspects, the shield part is a via having a conductor therein. According to this configuration, the shield part can be easily formed.

  According to a fifth aspect of the present invention, in the optical connector according to any one of the first to third aspects, the shield portion is a shield plate inserted into the slit. According to this configuration, the shield part can be easily formed.

  According to a sixth aspect of the present invention, in the optical connector according to the fifth aspect, the inner surface of the slit has a conductor electrically connected to the shield plate. According to this configuration, the shield plate constituting the shield portion can be easily connected to the ground.

  The invention according to claim 7 is the optical connector according to any one of claims 1 to 6, wherein the light receiving element and the receiving element, and the light emitting element and the transmitting element are electrically connected. The wiring connected to the wiring includes a via formed to extend from the bottom surface of the optical element placement recess to the bottom surface of the electrical element placement recess. According to this configuration, the via shortens the transmission path for transmitting a signal between the light receiving element and the receiving element, and between the light emitting element and the transmitting element, thereby reducing the inductance and capacitance in the transmission path and increasing the speed. Signal can be propagated to. In addition, by using a transmission line between the light receiving element and the receiving element as a via, the capacitance connected to the input of the receiving element is reduced, and the receiving sensitivity can be improved.

  According to an eighth aspect of the present invention, in the optical connector according to the seventh aspect, the optical connector includes a shield member that is formed inside the three-dimensionally molded circuit board and surrounds the via. According to this configuration, the shield member surrounding the via can make it difficult for noise to be received and received.

  The invention according to claim 9 is a three-dimensionally molded circuit board accommodated in an accommodating recess formed in a body holding a plurality of ferrules having an optical transmission medium, the first surface facing the tip of the ferrule An optical element disposing recess in which a light receiving element and a light emitting element are respectively disposed, and an electric element disposing recess in which a receiving element and a transmitting element are respectively disposed on a second surface different from the first surface. A wiring that electrically connects the light receiving element and the receiving element, and a wiring that electrically connects the light emitting element and the transmitting element, and is attached to a surface excluding the first surface, A connector header connected to each of the receiving element and the transmitting element and connected to a connector socket of a receptacle, and between the light receiving element and the light emitting element, from the first surface to the second surface. Heading Is formed in the building so has a shield section.

  According to this configuration, the shield portion formed between the light receiving element and the light emitting element is generated by a signal transmitted from the transmitting element to the light emitting element with respect to a signal transmitted from the light receiving element to the receiving element. Reduce the effect of noise. Therefore, a signal can be transmitted at high speed between the light receiving element and the receiving element and between the transmitting element and the light emitting element, and a three-dimensional molded circuit board having excellent EMC characteristics can be provided.

  According to the present invention, it is possible to provide an optical connector and a three-dimensionally molded circuit board that can transmit signals at high speed and have excellent EMC characteristics.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS.
As shown in FIG. 1, a receptacle 10 of an optical connector is mounted on a circuit board PB, and a plug 20 as an optical module of the optical connector is inserted and coupled to the receptacle 10 as shown in FIG.

  Two optical fibers F1 and F2 as optical transmission media are fixed to the plug 20. The plug 20 converts light transmitted through the optical fiber F1 into an electrical signal (OE conversion). The converted signal is transmitted to the circuit board PB via the receptacle 10. Further, the plug 20 converts an electric signal input from the circuit board PB via the receptacle 10 into light (EO conversion), and introduces the light into the optical fiber F2.

  As shown in FIG. 3, the receptacle 10 has a housing 11 formed in a rectangular cylinder shape, and a fixing pin 11 a is formed to protrude from the bottom of the housing 11. The fixing pin 11a is inserted into a fixing hole (not shown) formed in the circuit board PB shown in FIG. When the housing 11 and the fixing pin 11a are made of metal, the fixing pin 11a is soldered to a fixing pad (not shown) formed on the circuit board PB, and the receptacle 10 is fixed to the circuit board PB. When the housing 11 and the fixing pin 11a are formed of conductive resin, the receptacle 10 is fixed to the circuit board PB by attaching a fixing member such as a nut (not shown) to the fixing pin 11a. Moreover, the receptacle 10 may be surface-mounted and fixed to the circuit board PB by bending the fixing pin 11a in the middle of the length direction into an L shape.

  Connector sockets 13 a and 13 b are fixed in the housing 11. FIG. 3 shows only one connector socket 13b. Each of the connector sockets 13a and 13b includes a socket side terminal block 14 formed in a rectangular frame shape with an insulating resin, and a plurality of socket terminals 15 fixed to the socket side terminal block 14. Each socket terminal 15 is soldered to a pad (not shown) formed on the circuit board PB. Further, a rectangular locking hole 11 c is formed in the side wall 11 b of the housing 11.

  The plug 20 has a resin body 21 formed in a substantially rectangular parallelepiped shape. A plate-like fixing piece 21a is integrally formed on the body 21, and an engaging protrusion 21b is formed on the fixing piece 21a. The plug 20 is mounted and fixed to the housing 11 by engaging the engaging protrusion 21 b with the locking hole 11 c of the housing 11. Then, the plug 20 can be removed from the housing 11 by bending the fixing piece 21a to release the engagement state between the engagement protrusion 21b and the locking hole 11c.

  The body 21 is formed with a housing recess 21c into which the connector sockets 13a and 13b are inserted, on the surface facing the connector sockets 13a and 13b (bottom surface in FIG. 3), and the circuit block 22 is inserted into the housing recess 21c. It is fixed. The circuit block 22 is a three-dimensionally formed circuit board in which a conductor is formed three-dimensionally by forming a conductor on the surface of the insulator or on the surface and inside of the insulator. The circuit block 22 is formed of, for example, ceramic as an insulator, and is configured by copper plating as a conductor or metal plating in which a plurality of metals including copper are stacked. As an example, the conductor is made of laminated copper, nickel, and gold.

  As shown in FIG. 5, the circuit block 22 is formed in a rectangular parallelepiped shape. Further, as shown in FIG. 4, the circuit block 22 has two optical element placement recesses 23a and 23b and electrical element placement recesses 24a and 24b on two predetermined surfaces (upper surface and lower surface in this embodiment). Is formed. The surface on which the recesses 23a, 23b, 24a, 24b are formed is determined according to the direction in which the plug 20 is attached to and detached from the receptacle 10 and the direction in which the optical fibers F1, F2 are led out from the body 21 of the plug 20.

  As shown in FIG. 4, a light receiving element 25a is disposed in the recess 23a formed on the upper surface of the circuit block 22, and a light emitting element 25b is disposed in the recess 23b. The light receiving element 25a is, for example, a photodiode, and the light emitting element 25b is, for example, an LED or a surface emitting laser diode. The light receiving element 25a is electrically connected to the circuit pattern 27a formed in the recess 23a, and the light emitting element 25b is electrically connected to the circuit pattern 27b formed in the recess 23b.

  In a recess 24a formed on the lower surface of the circuit block 22 and corresponding to the recess 23a on the upper surface, a receiving element 28a constituting a receiving circuit is disposed, and below the recess 23b on the upper surface. In the formed recess 24b, a transmitting element 28b constituting a transmitting circuit is disposed. The receiving element 28a is electrically connected to the circuit pattern 29a formed in the recess 24a, and the transmitting element 28b is electrically connected to the circuit pattern 29b formed in the recess 24b.

  The circuit pattern 27a of the recess 23a is electrically connected to the circuit pattern 29a of the recess 24a via a circuit pattern 30a formed on the side surface of the circuit block 22. Similarly, the circuit pattern 27b of the recess 23b is electrically connected to the circuit pattern 29b of the recess 24b via a circuit pattern 30a formed on the side surface. With these circuit patterns, the light receiving element 25a is electrically connected to the receiving element 28a, and the light emitting element 25b is electrically connected to the transmitting element 28b.

  A light-transmitting resin 31 is filled and cured in the recess 23a in which the light receiving element 25a is disposed and the recess 23b in which the light emitting element 25b is disposed. An insulating sealant 32 is filled and cured in the recess 24a in which the receiving element 28a is disposed and the recess 24b in which the transmitting element 28b is disposed.

  Connector headers 33 a and 33 b are attached to the lower surface of the circuit block 22. The connector headers 33a and 33b are disposed and fixed so as to cover the receiving element 28a and the transmitting element 28b, respectively, from below. The connector headers 33a and 33b are each formed in a substantially rectangular parallelepiped shape and are fixed to the header side terminal block and the header side terminal block 34 formed so as to be inserted into the socket side terminal block 14 of the connector sockets 13a and 13b. And a plurality of header terminals 35. The header terminal 35 is electrically connected to the receiving element 28a and the transmitting element 28b through wiring patterns 36a and 36b formed in the circuit block 22.

  When the plug 20 is attached to the receptacle 10, the header terminal 35 is electrically connected to the socket terminals 15 of the connector sockets 13 a and 13 b provided on the receptacle 10. As described above, the socket terminal 15 is connected to a pad (not shown) formed on the circuit board PB.

  Therefore, the light receiving element 25a is connected to the receiving element 28a via the circuit patterns 27a, 30a, 29a, the receiving element 28a is connected to the header terminal 35 via the circuit pattern 36a, and the header terminal 35 is connected to the socket terminal 15. And connected to the circuit board PB. The receiving element 28a operates by a driving voltage supplied through the socket terminal 15, the header terminal 35, and the circuit pattern 36a. The light receiving element 25a operates by a driving voltage supplied from the receiving element 28a via the circuit patterns 36a, 30a, and 27a, and outputs a reception signal having a voltage (or current) corresponding to incident light to the receiving element 28a. . The receiving element 28a amplifies the received signal and outputs the amplified signal, or outputs a digital signal obtained by comparing the amplified signal with a threshold value using a comparator.

  Similarly, the light emitting element 25b is connected to the transmitting element 28b via the circuit patterns 27b, 30b, 29b, the transmitting element 28b is connected to the header terminal 35 via the circuit pattern 36b, and the header terminal 35 is a socket terminal. 15 is connected to the circuit board PB. The transmitting element 28b operates with a driving voltage supplied via the socket terminal 15, the header terminal 35, and the circuit pattern 36b. The transmitting element 28b supplies a drive voltage and a transmission signal to the light emitting element 25b via the circuit patterns 36b, 30b, and 27b. The light emitting element 25b operates by a driving voltage and emits light in response to a transmission signal.

  A shield pattern 37 is formed on the surface of the circuit block 22. The shield pattern 37 is formed so as to surround the circuit pattern formed on the surface of the circuit block 22. The shield pattern 37 is connected to the ground of the transmission circuit and the reception circuit. Since the circuit pattern formed in the circuit block 22 is surrounded by the shield pattern 37, the signal transmitted to the circuit pattern is not easily affected by external noise.

  As shown in FIG. 4, a ground layer 38 made of a conductor is formed inside the circuit block 22. The ground layer 38 is formed to extend in parallel with the surface on which the optical elements 25a and 25b and the electric elements 28a and 28b are mounted. Similarly to the shield pattern 37, the ground layer 38 is connected to the ground of the transmission circuit and the reception circuit. The ground layer 38 divides the circuit block 22 into an upper portion where the optical elements 25a and 25b are disposed and a lower portion where the electrical elements 28a and 28b are disposed. The ground layer 38 can prevent noise generated in the portion where the electric elements 28a and 28b are disposed from entering the portion where the optical elements 25a and 25b are disposed. In addition, since the circuit pattern can be a microstrip line by the ground layer 38 formed in this way, the impedance of the circuit pattern can be easily set.

  As shown in FIG. 5, the circuit block 22 has a plurality of vias 39 formed between the two recesses 23a and 23b. The via 39 is formed to extend along a first direction (vertical direction in FIG. 4) on a plane orthogonal to a line connecting the light receiving element 25a and the light emitting element 25b. The plurality of vias 39 are arranged along a second direction (the front and back direction in FIG. 4) that is on a plane orthogonal to the line connecting the light receiving element 25a and the light emitting element 25b and orthogonal to the first direction. Has been. Similar to the wiring pattern, a conductor plating 39a is formed on the inner peripheral surface of each via 39, and this plating 39a is connected to the ground of the circuit. The via includes a hole formed in the base material and a conductor inside the hole or inside the hole, and is formed in the conductor formed at the opening end of the hole or inside the base material. This means that the electrical conductors are electrically connected.

  The plurality of vias 39 formed in this way are a receiving element (light receiving element 25a and receiving element 28a and a wiring pattern connecting them), a transmitting element (light emitting element 25b and transmitting element 28b, and these elements). Functions as a shield pattern for separating the wiring pattern). Therefore, it is difficult for noise generated by the transmitting element 28b and the light emitting element 25b and the signal transmitted between them to be mixed into the weak signal transmitted between the light receiving element 25a and the receiving element 28a. . That is, the plurality of vias 39 reduce crosstalk between the reception circuit and the transmission circuit.

  As shown in FIG. 3, in the body 21, the light emitting element 25b of the circuit block 22 inserted and fixed in the housing recess 21c is disposed along the optical axis direction (vertical direction in FIG. 3) of each element 25b. An extending insertion hole 41 is formed. In the insertion hole 41, a ferrule 42 to which the optical fiber F2 is fixed is inserted. Further, the sealing material 43 is filled and cured in the insertion hole 41, and the ferrule 42 is fixed so that the light emitted from the light emitting element 25b by the sealing material 43 is introduced into the optical fiber fixed to the ferrule 42. Has been.

  Although not shown, similarly, an insertion hole is formed above the light receiving element 25a, and the light emitted from the optical fiber fixed to the ferrule is received by the light receiving element 25a in the ferrule inserted into the insertion hole. So as to be fixed by a sealing material.

Next, a method for forming the circuit block 22 will be described.
Schematically, the circuit block 22 is formed by laminating a plurality of insulator plates (ceramic plates). The circuit block 22 of the present embodiment is formed by stacking four ceramic plates.

  First, the 1st and 2nd ceramic board which formed the thin film of copper on the both surfaces of two ceramic boards is bonded together. Next, the 3rd and 4th ceramic board in which the square-shaped hole was formed is affixed on the upper surface and lower surface of two said ceramic plates bonded together. Recesses 23a and 23b are formed by the square holes formed in the third ceramic plate and the surface of the first ceramic plate, and the square holes and the second ceramic formed in the fourth ceramic plate. Concave portions 24a and 24b are formed by the surface of the plate. A ground layer 38 is formed by a copper thin film sandwiched between the first and second ceramic plates.

  Next, the surface of the block formed as described above is covered with a copper thin film by sputtering. The copper thin film formed on the surface is patterned by a laser processing apparatus to remove the outer copper thin film such as a circuit pattern.

Next, an electrode is connected to the copper thin film to be left, and copper plating is formed on the copper thin film by electrolytic plating. At this time, copper plating is not formed on the copper thin film to which no electrode is connected.
Next, copper is etched by soft etching. At this time, the copper thin film on which the copper plating is not formed is thin and is removed by etching.

Next, an electrode is connected to the remaining copper pattern, and nickel plating and gold plating are sequentially performed on the copper plating by electrolytic plating.
By this method, conductors are formed not only on the upper and lower surfaces but also on the side surfaces, the inner surfaces of the recesses 23 a to 24 b, and the inner peripheral surface of the via 39.

As described above, according to the present embodiment, the following effects can be obtained.
(1) A circuit block 22 is accommodated in the body 21 of the plug 20. On the upper surface of the circuit block 22, there are formed recesses 23a and 23b in which the light receiving element 25a and the light emitting element 25b are respectively disposed. On the lower surface of the circuit block 22, there are formed recesses 24a and 24b in which receiving elements 28a and transmitting elements 28b are respectively disposed. Connector headers 33a and 33b connected to the receiving element 28a and the transmitting element 28b are attached to the lower surface of the circuit block 22. In the circuit block 22, a plurality of vias 39 extending from the upper surface to the lower surface are formed between the light receiving element 25a and the light emitting element 25b, and a conductive plating 39a is formed on the inner peripheral surface of each via 39. Is formed.

  A plurality of vias 39 formed between the light receiving element 25a and the light emitting element 25b are signals transmitted from the transmitting element 28b to the light emitting element 25b in response to a signal transmitted from the light receiving element 25a to the receiving element 28a. This reduces the influence of noise generated by. Accordingly, it is possible to provide an optical connector having a plug 20 having excellent EMC characteristics and capable of transmitting signals between the light receiving element 25a and the receiving element 28a and between the transmitting element 28b and the light emitting element 25b at high speed. Can do.

  (2) The circuit block 22 has a shield pattern 37 that covers the surface. The shield pattern 37 can reduce the influence of external noise of the circuit block 22 on the signal transmitted from the light receiving element 25a to the receiving element 28a and the signal transmitted from the transmitting element 28b to the light emitting element 25b. it can. Further, it is possible to suppress the noise generated by the signal transmitted from the light receiving element 25a to the receiving element 28a and the signal transmitted from the transmitting element 28b to the light emitting element 25b from being radiated to the outside of the circuit block 22. it can. Therefore, it is possible to provide the plug 20 that can transmit signals at high speed and has excellent EMC characteristics.

  (3) The circuit block 22 has a ground layer 38. Therefore, since the ground layer 38 suppresses noise propagating between the light receiving element 25a and the receiving element 28a and between the light emitting element 25b and the transmitting element 28b, the optical connector having the plug 20 having excellent EMC characteristics. Can be provided.

  (4) The via 39 having the conductor plating 39 a is easily formed in the circuit block 22. Since the effect of noise generated by the signal transmitted from the transmitting element 28b to the light emitting element 25b is reduced with respect to the signal transmitted from the light receiving element 25a to the receiving element 28a by the via 39, the EMC characteristics are reduced. It is possible to easily form the circuit block 22 excellent in the above.

  (5) The light receiving element 25a and the light emitting element 25b are disposed in the recesses 23a and 23b, respectively, and the reception element 28a and the transmission element 28b are disposed in the recesses 24a and 24b, respectively. Therefore, the thickness of the circuit block 22 in the vertical direction can be reduced, and the plug 20 can be prevented from becoming longer.

(Second Embodiment)
A second embodiment embodying the present invention will be described below with reference to FIG. The same parts as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  As shown in FIG. 6, the circuit block 51 of this embodiment is formed in the same manner as the circuit block 22 of the first embodiment. The difference is that in the circuit block 51 of the present embodiment, a slit 52 extending along a plane perpendicular to a line connecting the light receiving element 25a and the light emitting element 25b is formed between the two recesses 23a and 23b. A shield plate 53 having conductivity is inserted in 52. The shield plate 53 is a copper plate, for example. The shield plate 53 is connected to the circuit ground in the same manner as the via 39 of the above embodiment.

  Thus, the shield plate 53 inserted into the slit 52 includes a receiving element (light receiving element 25a and receiving element 28a and a wiring pattern connecting them) and a transmitting element (light emitting element 25b and transmitting element 28b). And a wiring pattern that connects them) function as a shield pattern for electromagnetically separating them. Therefore, it is difficult for noise generated by the transmitting element 28b and the light emitting element 25b and the signal transmitted between them to be mixed into the weak signal transmitted between the light receiving element 25a and the receiving element 28a. . That is, the shield plate 53 reduces crosstalk between the reception circuit and the transmission circuit.

  The conductor 52 may be plated on the inner surface of the slit 52. Further, this plating may be connected to the circuit ground. Further, a convex portion may be formed on the plating so that the plating and the shield plate 53 are electrically connected.

As described above, according to the present embodiment, the following effects can be obtained.
(1) A slit 52 is formed in the circuit block 51, a shield plate 53 is inserted into the slit 52, and a signal transmitted from the light receiving element 25a to the receiving element 28a is transmitted to the light emitting element 25b from the transmitting element 28b. Since the influence of the noise generated by the signal transmitted to is reduced, the circuit block 51 having excellent EMC characteristics can be easily formed.

(Third embodiment)
Hereinafter, a third embodiment of the present invention will be described with reference to FIG. The same parts as those in the first and second embodiments are denoted by the same reference numerals and description thereof is omitted.

  As shown in FIG. 7, the circuit block 61 of this embodiment is formed similarly to the circuit block 22 of the first embodiment. The difference is that the circuit patterns 30a and 30b formed on the side surface of the circuit block 22 in the first embodiment are different from the circuit pattern 61 in the present embodiment in that vias 62a, 62b is formed. The via 62a is formed so as to reach the bottom surface of the recess 24a in which the receiving element 28a is disposed from the bottom surface of the recess 23a in which the light receiving element 25a is disposed. Similarly, the via 62b is formed so as to reach from the bottom surface of the recess 23b in which the light emitting element 25b is disposed to the bottom surface of the recess 24b in which the transmitting element 28b is disposed.

  That is, the circuit pattern 27 a connected to the light receiving element 25 a and the circuit pattern 29 a connected to the receiving element 28 a are linearly connected by the via 62 a formed in the circuit block 61. Similarly, the circuit pattern 27 b to which the light emitting element 25 b is connected and the circuit pattern 29 b to which the transmitting element 28 b is connected are linearly connected by a via 62 b formed in the circuit block 61. The vias 62a and 62b include an internal conductor.

  Accordingly, the length of the circuit pattern that connects the light receiving element 25a and the receiving element 28a and the length of the circuit pattern that connects the light emitting element 25b and the transmitting element 28b are extremely short. For this reason, since the values of the inductance and capacitance of the circuit pattern become small, it is suitable for high-speed communication. The vias 62 a and 62 b formed in the circuit block 61 are surrounded by a shield pattern 37 on the surface of the circuit block 61. For this reason, noise generated from the vias 62a and 62b is less likely to go out of the circuit block 61, and signals transmitted through the vias 62a and 62b are not easily affected by noise outside the circuit block 61.

  Further, a via 39 connected to the ground is formed between the via 62a connecting the light receiving element 25a and the receiving element 28a and the via 62b connecting the light emitting element 25b and the transmitting element 28b. It is possible to reduce crosstalk in which noise radiated from the via 62b to which the trust signal is transmitted is mixed into the reception signal transmitted through the via 62a.

As described above, according to the present embodiment, the following effects can be obtained.
(1) The light receiving element 25a and the receiving element 28a, and the light emitting element 25b and the transmitting element 28b are connected by vias 62a and 62b. Accordingly, the vias 62a and 62b shorten the transmission path for transmitting signals between the light receiving element 25a and the receiving element 28a, and between the light emitting element 25b and the transmitting element 28b, so that the inductance and capacitance in the transmission path are small. Thus, the signal can be propagated at high speed. Further, by connecting via the via 62a between the light receiving element 25a and the receiving element 28a, the capacitance connected to the input of the receiving element 28a is reduced, and the receiving sensitivity can be improved.

(Fourth embodiment)
Hereinafter, a fourth embodiment of the present invention will be described with reference to FIG. The same parts as those in the first to third embodiments are denoted by the same reference numerals and description thereof is omitted.

  As shown in FIG. 8, the circuit block 71 of the present embodiment surrounds vias 62a and 62b as circuit patterns formed in the circuit block 71 in addition to the circuit block 61 of the third embodiment. Shield patterns 72a and 72b as shield members are formed. The shield patterns 72a and 72b are connected to the ground of the circuit as in the above embodiments. Therefore, compared with the third embodiment, noise generated from the vias 62a and 62b is less likely to go out of the circuit block 71, and a signal transmitted through the vias 62a and 62b is external to the circuit block 71. It becomes less susceptible to noise.

As described above, according to the present embodiment, the following effects can be obtained.
(1) The vias 62a and 62b formed in the circuit block 71 are surrounded by shield patterns 72a and 72b, respectively. Therefore, noise is less likely to be radiated to the outside from the vias 62a and 62b, and signals propagating through the vias 62a and 62b can be made less susceptible to noise.

In addition, you may implement each said embodiment in the following aspects.
Each embodiment described above is embodied as a plug including a set of light receiving elements 25a and light emitting elements 25b, but may be embodied as a plug including a plurality of sets of light receiving elements 25a and light emitting elements 25b. For example, you may comprise as shown to Fig.9 (a) and FIG.9 (b). FIGS. 9A and 9B show only electrical connectors (connector headers 33a and 33b) connected to the light receiving element 25a and the light emitting element 25b.

  The plug 81 shown in FIG. 9A includes four circuit blocks of the above embodiment (for example, the circuit block 22 of the first embodiment). The plug 81 thus configured can collectively connect optical fibers used for transmission / reception of a plurality of channels.

  In the plug 91 shown in FIG. 9B, four sets of light receiving elements and light emitting elements are arranged in one circuit block 92. In this case, vias 39 for shielding may be formed between the connector headers 33b respectively connected to the light emitting elements, and crosstalk between transmission channels arranged adjacent to each other can be reduced. A via 39 may be formed between the connector headers 33a connected to the light receiving elements.

  In each of the above embodiments, as in the second embodiment, the slit 52 may be formed instead of the via 39 and the shield plate 53 may be inserted into the slit 52. Further, in the plug 81 shown in FIG. 9A, the circuit blocks 22, 51, 61, 71 of the respective embodiments may be mixed. In the plug 91 shown in FIG. 9B, the via 39, the slit 52, and the shield plate 53 may be formed in the circuit block 92.

  In the second embodiment, the shape of the shield plate 53 may be changed as appropriate. For example, the shield plate 53 is formed of a single metal plate, formed of a metal plate having slits or through holes, a metal body having a mesh structure, a plurality of thin metal plates are stacked, and the like. Various forms may be adopted.

The perspective view of a plug and a receptacle. FIG. 3 is a perspective view of a combined plug and receptacle. Sectional drawing of a plug and a receptacle. Sectional drawing of the circuit block of 1st Embodiment. The perspective view of the circuit block. The perspective view of the circuit block of 2nd Embodiment. Sectional drawing of the circuit block of 3rd Embodiment. Sectional drawing of the circuit block of 4th Embodiment. (A) and (b) are bottom views of another optical plug.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Receptacle, 13a, 13b ... Connector socket, 15 ... Socket terminal,
DESCRIPTION OF SYMBOLS 20 ... Plug, 21 ... Body, 21c ... Accommodating recessed part, 22, 51, 61, 71 ... Circuit block, 23a, 23b ... Recessing part for optical element arrangement, 24a, 24b ... Recessing part for electric element arrangement, 25a ... Light receiving element, 25b ... light emitting element, 28a ... receiving element, 28b ... transmitting element, 33a, 33b ... connector header, 37 ... shield pattern, 38 ... ground layer, 42 ... ferrule, 52 ... slit, 53 ... shield plate.

Claims (9)

An optical connector having a receptacle and an optical module connected to the receptacle,
The optical module is
A body that holds a plurality of ferrules having an optical transmission medium and is formed with an accommodation recess,
A three-dimensionally molded circuit board housed in the housing recess,
The three-dimensional molded circuit board is
A recess for arranging optical elements in which a light receiving element and a light emitting element are respectively arranged on a first surface facing the tip of the ferrule;
A recess for electric element arrangement in which a receiving element and a transmitting element are respectively arranged on a second surface different from the first surface;
Wiring for electrically connecting the light receiving element and the receiving element, and wiring for electrically connecting the light emitting element and the transmitting element;
A connector header attached to a surface excluding the first surface, connected to the receiving element and the transmitting element, and connected to a connector socket of the receptacle;
A shield portion formed between the light receiving element and the light emitting element so as to extend from the first surface toward the second surface;
An optical connector comprising:   The optical connector according to claim 1, wherein the three-dimensionally molded circuit board has a shield pattern that covers a surface.   3. The three-dimensionally shaped circuit board has a ground layer formed between the light receiving element and the receiving element and between the light emitting element and the transmitting element. The optical connector described.   The optical connector according to claim 1, wherein the shield part is a via having a conductor inside.   The optical connector according to claim 1, wherein the shield part is a shield plate inserted into a slit.   The optical connector according to claim 5, further comprising a conductor electrically connected to the shield plate on an inner surface of the slit.   The wiring for electrically connecting the light receiving element and the receiving element, and the light emitting element and the transmitting element is formed to extend from the bottom surface of the recess for arranging the optical element to the bottom surface of the recess for arranging the electric element. The optical connector according to claim 1, further comprising a via having a conductor.   The optical connector according to claim 7, further comprising a shield member formed inside the three-dimensionally molded circuit board and surrounding the via. A three-dimensionally molded circuit board accommodated in an accommodating recess formed in a body holding a plurality of ferrules having an optical transmission medium,
An optical element disposition recess in which a light receiving element and a light emitting element are respectively disposed is formed on a first surface facing the tip of the ferrule, and a receiving element and a transmitting element are formed on a second surface different from the first surface. A wiring for electrically connecting the light receiving element and the receiving element, and a wiring for electrically connecting the light emitting element and the transmitting element are formed. A connector header connected to the receiving element and the transmitting element and connected to the connector socket of the receptacle is attached to the surface excluding the first surface,
A three-dimensional molded circuit board.

Images