JP2009058747A - Optoelectronic circuit board and inspecting device of the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optoelectronic circuit board that can inspect failures in a light receiving/emitting light part and an optical transmission path after being mounted on a circuit board of the light receiving/emitting part, and to provide an inspecting device the same. <P>SOLUTION: A substrate 10 is provided with, on a second board 10B side thereof, a photoreceiver 14 for receiving light emitted from a light emitting element 125 of a first optical module 12A. The photoreceiver 14 is provided so as to be located in an opening 10b provided in the second board 10B so that part of the light incident from an opening 10a provided in a first board 10A may transmit through an optical waveguide 10C; and the photoreceiver 14 photoelectrically converts light reception signals that corresponds to light intensity of the received light to output the converted signals as analog signals. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an optoelectronic circuit board and an inspection apparatus for an optoelectronic circuit board.

  Optical communication technology using light as an information transmission medium has become widespread. In such an optical communication technology, in order to transmit an optical signal obtained by modulating light with a signal indicating information, conventionally, an optical mounting substrate in which an optical waveguide is built in the substrate has been proposed (for example, see Non-Patent Document 1). ).

This optical mounting board has a printed wiring board in which optical waveguides having optical path conversion surfaces at both ends are built, a light emitting element mounted on the lower surface of the submount, and a light emitting side optical device mounted with a driver on the upper surface, Light receiving side light that is electrically connected to the printed wiring board by solder balls so that the light emitting element is positioned directly above one optical path conversion surface, the light receiving element is mounted on the lower surface of the submount, and the receiver is mounted on the upper surface. The device has a structure in which a light receiving element is electrically connected to a printed wiring board by a solder ball so that the light receiving element is positioned immediately above the other optical path conversion surface.
Journal of Japan Institute of Electronics Packaging Vol.8 No.1 (2005), p.29-32

  An object of the present invention is to provide an optoelectronic circuit board and an optoelectronic circuit board inspection apparatus capable of inspecting defects of the light emitting / receiving section and the optical transmission path after mounting the light emitting / receiving section on the circuit board.

  In order to achieve the above object, one embodiment of the present invention provides the following optoelectronic circuit board.

(1) a first substrate having a mounting surface on which an optical module having a light emitting element is mounted;
A core provided on a surface opposite to the mounting surface of the first substrate and having a core for propagating light emitted from the light emitting element and a clad covering the core; An optical waveguide provided with an optical path conversion surface;
A second substrate provided on a surface of the optical waveguide opposite to the surface on which the first substrate is provided, and provided with a light emitting portion that emits light emitted from the light emitting element via the optical waveguide; An optoelectronic circuit board.

(2) The optoelectronic circuit board according to (1), wherein the light emitting portion is an opening provided in the second substrate corresponding to the light incident position.

(3) The optoelectronic circuit board according to (1), wherein the light emitting portion is an opening provided in the second substrate corresponding to the light emitting position.

(4) The optoelectronic circuit board according to (1), wherein the optical path conversion surface has a reflective surface smaller than a diameter of light emitted from the light emitting element.

(5) The first optical path conversion surface provided so that the light is incident on the core and the clad at the light incident position,
The optoelectronic circuit board according to (1), further comprising: a second optical path conversion surface that converts the light reflected by the first optical path conversion surface and propagated through the clad into an optical path and emits the light from the light emitting unit.

(6) The optical path conversion surface is a first optical path conversion surface provided in the light incident position with a size smaller than the size of the core;
The light emitting position is provided with a size smaller than the size of the core, and a part of the light reflected by the first optical path conversion surface and propagated through the core is optically converted and emitted from the light emitting unit. The optoelectronic circuit board according to (1), further including a second optical path conversion surface.

  In order to achieve the above object, one embodiment of the present invention provides the following optoelectronic circuit board inspection apparatus.

(7) a first substrate having a mounting surface on which an optical module having a light emitting element is mounted; an optical waveguide provided on a surface opposite to the mounting surface of the first substrate; and the first of the optical waveguides An optoelectronic circuit board having a second substrate provided on a surface opposite to the surface on which the first substrate is provided;
A power supply unit that applies a driving voltage to the light emitting element of the optical module mounted on the mounting surface of the first substrate;
A light-receiving unit that receives inspection light emitted from the light-emitting element based on application of the drive voltage via the first substrate, the optical waveguide, and the second substrate;
An inspection apparatus for an optoelectronic circuit board, comprising: a signal detection unit that outputs a detection signal based on reception of the inspection light.

(8) The optoelectronic circuit board according to (7), wherein the light receiving section is provided so as to be positioned in an opening provided in the first and second substrates according to a light incident position on the optical waveguide. Inspection equipment.

(9) The light receiving unit includes a first light receiving unit provided to be positioned at a first opening provided in the second substrate according to a light incident position on the optical waveguide, and the optical waveguide. The inspection apparatus for an optoelectronic circuit board according to (7), further comprising: a second light receiving portion provided so as to be positioned in a second opening provided in the second substrate in accordance with the light emission position of the first and second substrates.

  According to the optoelectronic circuit board according to the first aspect, it is possible to inspect defects of the light emitting / receiving section and the optical transmission path after mounting the light receiving / emitting section on the circuit board.

  According to the optoelectronic circuit board of the second aspect, it is possible to inspect a defect of the light emitting element based on the light emitted from the light emitting portion.

  According to the optoelectronic circuit board according to the third aspect, it is possible to inspect the defects of the light emitting element and the optical waveguide based on the light emitted from the light emitting portion.

  According to the optoelectronic circuit board according to the fourth aspect, the light emitted from the light emitting element can be emitted from the light emitting portion.

  According to the optoelectronic circuit board of the fifth aspect, it is possible to inspect a defect of the optical waveguide based on the light propagated through the clad.

  According to the optoelectronic circuit board according to the sixth aspect, it is possible to inspect the defect of the optical waveguide based on the light propagated through the core.

  According to the inspection apparatus for an optoelectronic circuit board according to the seventh aspect, it is possible to inspect defects of the light emitting / receiving section and the optical transmission path after mounting the light emitting / receiving section on the circuit board.

  According to the optoelectronic circuit board inspection apparatus of the eighth aspect, it is possible to inspect the light emitting state of the light emitting element.

  According to the optoelectronic circuit board inspection apparatus of the ninth aspect, it is possible to inspect the light emitting state of the light emitting element and the light transmission state of the optical waveguide.

[First embodiment]
(Configuration of optoelectronic circuit board)
FIG. 1 shows a schematic configuration of an optoelectronic circuit board according to a first embodiment of the present invention, wherein (a) is a perspective view of the optoelectronic circuit board, and (b) is an optoelectronic circuit in the AA portion of (a). The longitudinal cross-sectional view of the center part of a board | substrate, (c) is a cross-sectional view of the optoelectronic circuit board in the BB part of (a).

  As shown in FIG. 1A, the optoelectronic circuit board 1 includes a substrate 10 configured by laminating an optical waveguide 10C between a first substrate 10A and a second substrate 10B, and one of the optical waveguides 10C. A first optical module 12A mounted on the substrate 10 positioned on the side (transmitting side) and a second optical module 12B mounted on the substrate 10 positioned on the other side (receiving side) of the optical waveguide 10C. It is configured. The first optical module 12A and the second optical module 12B receive and transmit the optical signal 2 through the core layer 100 of the optical waveguide 10C.

  The first substrate 10A of the optoelectronic circuit board 1 is provided with inspection terminals 1A, 1B, 1D, 1E and an inspection ground 1C for causing a light emitting element of the optical module to emit light by an inspection device 20 described later.

  The inspection terminal 1A is for driving the light emitting element of the first optical module 12A, the inspection terminal 1B is for outputting the light receiving element of the first optical module 12A, and 1C is an inspection ground for the optoelectronic circuit board 1, The terminal 1D is for driving the light emitting element of the second optical module 12B, and the inspection terminal 1E is for outputting the light receiving element of the second optical module 12B.

  As shown in FIG. 1B, the optical waveguide 10 </ b> C includes a core layer 100 and a clad layer 101 having a refractive index smaller than that of the core layer 100, and the core layer 100 is sandwiched between the clad layers 101. It has a structure. The optical waveguide 10C can be manufactured by, for example, a method using photolithography or reactive ion etching (RIE) that is generally used. In particular, it can be efficiently produced by a production process using a mold described in Japanese Patent Application Laid-Open No. 2004-29507 already proposed by the present applicant.

  FIG. 2 is a partial cross-sectional view of the first optical module section obtained by cutting the optoelectronic circuit board at the AA portion in FIG. 1A, and FIG. 3 shows the optoelectronic circuit board at the AA section in FIG. It is the fragmentary sectional view in the cut 2nd optical module part.

  The first optical module 12A and the second optical module 12B have a ball grid array (BGA) that connects a terminal 120 provided for external connection and a terminal 110A provided on the first substrate 10A of the substrate 10 via a solder ball 121. ) Type optical module.

  As shown in FIG. 2, the first optical module 12 </ b> A is fixed to a support substrate 122 on which electronic components such as a large scale integrated circuit (LSI) can be mounted, and a back surface side of the support substrate 122 on the solder ball 121 bonding side. The light emitting element 125 electrically connected to the terminal 124 through the wire 123, the control unit 126 such as LSI fixed to the surface side opposite to the side on which the light emitting element 125 is fixed, and the support substrate 122 A terminal 127 that penetrates and is electrically connected to the solder ball 121 on the back surface side and is electrically connected to the controller 126 via the wire 123, and the controller 126, the wire 123, and the terminal 127 on the surface of the support substrate 122. And a sealing resin 128 for sealing.

  The first optical module 12 </ b> A has a light receiving element that receives an optical signal transmitted from the second optical module 12 </ b> B, which will be described later, on the back side of the support substrate 122.

  The first optical module 12A is provided on the first substrate 10A so that the light emitting element 125 emitting light in the direction of the substrate 10 and the cladding layer 101 of the optical waveguide 10C provided in the substrate 10 can be optically coupled. The light emitting element 125 is fixed so as to be positioned in the opening 10a.

  In addition, a light receiver 14 that receives light emitted from the light emitting element 125 of the first optical module 12A is provided on the second substrate 10B side of the substrate 10. The light receiver 14 is positioned in the opening 10b provided in the second substrate 10B so that a part of the optical signal 2 incident from the opening 10a provided in the first substrate 10A is transmitted through the optical waveguide 10C. A received light signal corresponding to the light intensity of the received light signal 2 is photoelectrically converted and output as an analog signal.

  The light receiver 14 is connected to the inspection apparatus 20. The inspection apparatus 20 includes an operation unit 21 that performs an input operation by an operator for inspecting the first optical module 12A and the substrate 10, and a signal conversion unit that converts an analog signal input from the light receiver 14 into a digital signal and outputs the digital signal. 22, a display unit 23 composed of a display such as a color liquid crystal panel that performs screen display based on the detection result of the light receiver 14, a power supply unit 24 that generates a driving voltage based on the execution of the inspection, and each unit of the inspection apparatus 20. The power supply unit 24 includes a control unit 25 for controlling, and a voltage detection probe 27 for applying a drive voltage connected to the power supply unit 24 via a power supply line 26. The power supply unit 24 includes a test ground 1C as a configuration (not shown). A ground line is connected between the two.

  The above-described light receiver 14, the power supply line 26 including the ground line, and the voltage detection probe 27 are also included in the inspection apparatus 20.

  For the light receiver 14, for example, a planar optical element such as a planar photodiode can be used. In this embodiment, a GaAs PIN photodiode excellent in high-speed response is used as the light receiving element.

  As shown in FIG. 3, the second optical module 12B is fixed to the first substrate 10A so that the light receiving element 129 is positioned on the optical path capable of receiving the optical signal 2 from the core layer 100 of the optical waveguide 10C. Other than that, the configuration is the same as that of the first optical module 12A. The light receiving element 129 receives the optical signal 2 whose optical path has been changed by the mirror 10D from the core layer 100 of the optical waveguide 10C through the opening 10a provided in the first substrate 10A.

  The second optical module 12B has a light emitting element that transmits an optical signal 2 to the first optical module 12A on the back side of the support substrate 122.

(Light emitting element)
As the light emitting element 125, a light emitting element (surface type optical element) such as a surface type light emitting diode or a surface type laser can be used. In this embodiment mode, a VCSEL (surface emitting laser) is used as the light emitting element 125, and the emission wavelength is 850 nm.

  In this surface emitting laser, for example, an n-type lower reflector layer, an active layer, a current confinement layer, a p-type upper reflector layer, a p-type contact layer, and a p-side electrode are formed on an n-type GaAs substrate. An n-side electrode is formed on the back surface of the GaAs substrate, and the p-side electrode has an opening immediately above the light emitting region of the active layer.

  Note that although one light-emitting element is provided in this embodiment, a plurality of light-emitting elements arranged in an array can also be used.

(Light receiving element)
As the light receiving element 129, for example, a planar optical element such as a planar photodiode can be used. In this embodiment, a GaAs PIN photodiode excellent in high-speed response is used as the light receiving element.

  The light receiving element 129 includes, for example, a P-layer, an I-layer, and an N-layer that are PIN-bonded on a GaAs substrate, a p-side electrode connected to the P-layer, and an n-side electrode formed on the N layer. The p-side electrode has an opening, and the inside of the opening serves as a light receiving portion that receives laser light.

  In the present embodiment, the number of light receiving elements is one, but a plurality of light receiving elements corresponding to the plurality of light emitting elements on the transmission side may be arranged in an array.

(Support substrate)
The support substrate 122 of the first optical module 12A and the second optical module 12B is formed of an insulating material such as glass epoxy resin, and a terminal formed of a conductive material such as copper on the back surface on the mounting side to the external circuit. 120. A part of the terminal 120 is connected to a terminal or a wiring pattern formed of a conductive material such as copper on the surface to which the control unit 126 is fixed through a through hole.

  As for the light emitting element 125, the n-side electrode is bonded to the ground formed on the back surface of the support substrate 122 by the same conductive material as the terminal 120 shown in FIG. The p-side electrode of the light emitting element 125 and the terminal 124 are connected by a wire 123 made of gold or the like.

  For the light receiving element 129, the n-side electrode is bonded to the ground formed on the back surface of the support substrate 122 by the same conductive material as the terminal 120 shown in FIG. The p-side electrode of the light receiving element 129 and the terminal 124 are connected by a wire 123 made of gold or the like.

  Note that the support substrate 122 may be configured to be mounted on another circuit board. For example, a terminal formed on the surface of the support substrate 122 and a ground are connected to a solder ball 121 provided on the back surface of the support substrate 122 through a through hole, and the support substrate 122 is connected to another circuit via the solder ball 121. You may mount on a board | substrate.

(Control part)
The control unit 126 includes a drive circuit that drives the light emitting element 125 and an amplification circuit that amplifies the electrical signal photoelectrically converted based on light received by the light receiving element 129.

(Sealing resin)
The sealing resin 128 is made of a thermosetting molding material such as an epoxy resin, and protects the wire 123, the control unit 126, and the terminal 127 from the environment such as light, heat, and humidity. An epoxy resin as a main component and a filler such as silica may be added.

(substrate)
The substrate 10 is formed of an insulating material such as glass epoxy resin for the first substrate 10A and the second substrate 10B. 10 A of 1st board | substrates have the terminal 110A formed from electroconductive materials, such as copper, on the surface.

  As shown in FIG. 2, the first substrate 10A has an opening 10a for optically coupling the light emitting element 125 and the core layer 100 of the optical waveguide 10C provided on the substrate 10 at a position where the first optical module 12A is provided. Have. Note that the opening 10a may be filled with a light-transmitting material that is transparent to the wavelength of light emitted from the light emitting element 125, as long as optical coupling with the core layer 100 of the optical waveguide 10C is possible. .

  Further, as shown in FIG. 3, the first substrate 10A has an opening for optically coupling the light receiving element 129 and the core layer 100 of the optical waveguide 10C provided on the substrate 10 at a position where the second optical module 12B is provided. 10a. The opening 10a may also be filled with a light transmissive material that is transparent to the wavelength of light emitted from the light emitting element 125, as long as optical coupling with the core layer 100 of the optical waveguide 10C is possible.

  As shown in FIG. 2, the second substrate 10B has an opening 10b for extracting the optical signal 2 on the second substrate 10B side at the same position as the position where the opening 10a of the first substrate 10A is provided. . The opening 10b may also be filled with a light transmissive material that is transparent to the wavelength of light emitted from the light emitting element 125.

(Optical waveguide)
The optical waveguide 10 </ b> C includes a core layer 100 and a cladding layer 101 formed around the core layer 100. In the core layer 100, a mirror 10D as an optical path conversion surface inclined at 45 degrees is formed at a position corresponding to the opening 10a of the first substrate 10A. The mirror 10D is provided on the optical path between the light emitting element 125, the core layer 100, and the light receiving element 129. The periphery of the mirror 10D is filled with a light transmissive resin 10E having a refractive index equivalent to that of the cladding layer 101, and the surface of the mirror 10D is covered with the light transmissive resin 10E.

  For example, the optical waveguide 10 </ b> C is formed with a layer thickness including the core layer 100 and the clad layer 101 of 100 to 200 μm.

  For the production of the optical waveguide 10 </ b> C, first, a mold having a recess corresponding to the core layer 100 is produced.

  Next, the clad film substrate is brought into intimate contact with the mold, and the concave portion of the mold is filled with a curable resin.

  Next, the curable resin in the recess is cured to form the core layer 100, and then the mold is peeled off. As a result, the core layer 100 is left on the clad film substrate to be the clad layer 101.

  Next, the clad layer 101 is provided on the surface of the clad film substrate on which the core layer 100 is formed so as to cover the core layer 100. In the present embodiment, the mirror 10D is provided on the core layer 100 of the optical waveguide 10C thus formed.

  4A and 4B are diagrams illustrating a process of providing a mirror as an optical path conversion surface on an optical waveguide.

  First, as shown in FIG. 4A (a), an optical waveguide 10C composed of the core layer 100 and the clad layer 101 described above is prepared.

  Next, as shown in FIG. 4A (b), the optical waveguide 10C is grooved so as to have a 45-degree inclined surface 103A by making a cut with a dicer at a predetermined position as the light incident position on the core layer 100. 103 is formed. The core layer 100 is exposed in the groove 103.

  Next, as shown in FIG. 4A (c), a photoresist 104 is formed on the side where the groove 103 of the optical waveguide 10C is formed.

  Next, as shown in FIG. 4A (d), a photomask having a mask pattern corresponding to the shape of the mirror formed on the end surface of the core layer 100 is overlaid on the surface where the photoresist 104 is formed, and the photoresist 104 is exposed. Thereafter, the photoresist 105 is partially removed by etching to form the opening 105.

  Next, as shown in FIG. 4B (e), a mirror 10D as a light reflecting film is formed on the core layer 100 exposed at the inclined surface 103A of the groove 103 by a thin film forming method such as vapor deposition. As the mirror 10D, for example, a metal film such as Au or Al, or a film having a metallic luster such as TiN can be provided.

  Next, as shown in FIG. 4B (f), the photoresist 104 is removed from the optical waveguide 10C on which the mirror 10D is formed.

  Next, as shown in FIG. 4B (g), the groove 103 in which the mirror 10D is formed on the inclined surface 103A is filled with a light-transmitting resin 10E having a refractive index equivalent to that of the cladding layer 101. As a result, an optical waveguide 10 </ b> C that includes the mirror 10 </ b> D as an optical path conversion surface having an inclination angle of 45 degrees with respect to the formation direction of the core layer 100 and does not perform optical path conversion in portions other than the mirror 10 </ b> D is obtained.

  FIGS. 5A and 5B are diagrams showing a process of integrating the optical waveguide with the first substrate and the second substrate.

  First, as shown in FIG. 5A, the second substrate 10B is positioned so that the mirror 10D formed on the core layer 100 is disposed at the position of the opening 10b with respect to the lower surface of the optical waveguide 10C. Next, the second substrate 10B is bonded to the positioned second substrate 10B by an adhesive such as a thermosetting adhesive so that the opening 10b is positioned at a portion where the mirror 10D is provided.

  Next, as shown in FIG. 5B, the first substrate 10A is positioned so that the mirror 10D formed in the core layer 100 is disposed at the position of the opening 10a with respect to the upper surface of the optical waveguide 10C. . Next, 10 A of positioned 1st board | substrates are joined to an upper surface by adhesives, such as a thermosetting adhesive, and it is set as the board | substrate 10. FIG.

  In addition, although the above-described process was described on the light incident position side of the optical waveguide 10C, it is similarly formed on the light emitting position side. Alternatively, the first substrate 10A may be bonded first to the optical waveguide 10C, and then the second substrate 10B may be bonded. Further, the first substrate 10A and the second substrate 10B can be bonded simultaneously.

(Operation of optoelectronic circuit board)
The operation of the optoelectronic circuit board according to the first embodiment will be described below with reference to FIGS.

(Transmission and reception of optical signals)
For example, when the image signal is transmitted to the second optical module 12B, the control unit 126 of the first optical module 12A outputs a control signal to the drive circuit based on the image signal. The drive circuit performs energization control to the light emitting element 125 based on the control signal. The light emitting element 125 emits laser light having a wavelength of 850 nm by applying a voltage between the p-type electrode and the n-type electrode based on energization.

  As shown in FIG. 2, the optical signal 2 of the laser beam emitted from the light emitting element 125 enters the optical waveguide 10C through the opening 10a, is reflected by the mirror 10D provided in the core layer 100, and is 90 degrees. It propagates in the core layer 100 by changing the optical path. In the optical waveguide 10 </ b> C, since the mirror 10 </ b> D is provided in the core layer 100, the optical signal 2 incident from the opening 10 a does not enter the cladding layer 101. With such a configuration, light propagated through the cladding layer 101 by the second optical module 12B is not received, noise is not included in the optical signal 2, and occurrence of bit errors can be prevented.

  As shown in FIG. 3, the optical signal 2 propagated through the core layer 100 is incident on a mirror 10 </ b> D provided on the light emission position side of the core layer 100. The mirror 10D reflects the optical signal 2 propagated through the core layer 100 and changes the optical path by 90 degrees. The optical signal 2 whose optical path has been changed is emitted from the opening 10a and enters the light receiving element 129 of the second optical module 12B.

  The light receiving element 129 generates a voltage between the p-side electrode and the n-side electrode according to the light intensity of the incident optical signal 2, and outputs a current based on this voltage to the control unit 126. The control unit 126 performs signal processing after the current output from the light receiving element 129 is amplified by an amplifier circuit.

  The first optical module 12A and the second optical module 12B transmit and receive the optical signal 2 through the optical waveguide 10C provided on the substrate 10 as described above. Thus, in the configuration of the optoelectronic circuit board 1 in which the optical waveguide 10C is provided in the substrate 10, even if some abnormality or damage occurs in the optical waveguide 10C, it is difficult to grasp the abnormality from the outside.

  Furthermore, since the first optical module 12A and the second optical module 12B are surface-mounted on the substrate 10 and the light emitting / receiving section is not exposed, it is difficult to directly inspect the light emitting element 125 and the light receiving element 129. . Below, the inspection method of the optoelectronic circuit board 1 in this Embodiment is demonstrated.

(Inspection of optoelectronic circuit board)
FIG. 6 is a flowchart illustrating the inspection of the first optical module according to the first embodiment.

  First, as shown in FIG. 2, the operator places the light receiver 14 at the position of the opening 10b of the second substrate 10B (S1).

  Next, the operator operates the operation unit 21 of the inspection apparatus 20 to perform initial setting, and enters a standby state in which a drive voltage can be supplied from the power supply unit 24 (S2).

  Next, the operator connects a ground wire to the inspection ground 1C and brings the voltage detection probe 27 into contact with the inspection terminal 1A (S3). In a situation where the light emitting element 125 operates normally without any abnormality, a driving voltage is supplied from the inspection terminal 1A to the light emitting element 125 of the first optical module 12A by bringing the voltage detection probe 27 into contact therewith. The light emitting element 125 emits light based on the driving voltage and emits an optical signal 2 as inspection light.

  The operator monitors the screen display of the display unit 23 to check whether or not the output of the light receiver 14 has changed. When it is confirmed on the screen display that the light intensity exceeding the threshold and the ON / OFF signal corresponding to the input signal are obtained (S4: Yes), the light emitting element 125 of the first optical module 12A is operating normally. Judgment is made (S5). In addition, when it is confirmed by the screen display that the light intensity is equal to or less than the threshold value or there is no output from the light receiver 14 (S4: No), the light emitting element 125 of the first optical module 12A has a light emission failure. Judgment is made (S6).

[Second Embodiment]
(Configuration of optoelectronic circuit board)
FIG. 7 is a schematic configuration diagram of an optoelectronic circuit board and an inspection apparatus according to the second embodiment of the present invention. In the figure, optical transmission from the first optical module 12A to the second optical module 12B is shown, and the substrate 10 is shown in a sectional view. In the following description, portions having the same configuration and function as those of the first embodiment are denoted by common reference numerals.

  In addition to the configuration on the first optical module 12A side described in the first embodiment, the optoelectronic circuit board 1 has an optical path conversion surface to the light receiving element 129 and inspection light on the optical waveguide 10C on the second optical module 12B side. The configuration having the optical path conversion surface for extraction is different from the first embodiment.

  The inspection apparatus 20 includes a light receiver 14A provided on the light incident position side of the optoelectronic circuit board 1, and a signal converter 22A that converts an analog signal input from the light receiver 14A into a digital signal and outputs the digital signal. Moreover, it has the light receiver 14B provided in the light emission position side of the optoelectronic circuit board 1, and the signal conversion part 22B which converts the analog signal input from the light receiver 14B into a digital signal, and outputs it. Further, a signal line 28 that outputs a signal based on light reception of the light receiving element 129 to the signal conversion unit 22B is connected to the inspection terminal 1E on the second optical module 12B side.

  On the light incident position side, the mirror 10 </ b> D on the light incident position side provided in the cladding layer 101 of the optical waveguide 10 </ b> C is formed larger than the size of the core layer 100. At this light incident position, the optical signal 2 whose optical path has been changed is incident on the core layer 100 and the clad layer 101. Further, the optical signal 2 that is not subjected to optical path conversion by the mirror 10D enters the light receiver 14A through the opening 10b.

  On the light emission position side, a mirror 10F formed with the same size as the core layer 100 and a mirror 10G for optical path conversion of the optical signal 2 propagated through the cladding layer 101 with a size larger than the core layer 100 at the subsequent stage of the mirror 10F are provided. Have. The first substrate 10A is provided with an opening 10a, and the second substrate 10B is provided with an opening 10b. The openings 10a and 10b are located at portions where the mirrors 10F and 10G are formed. At this light emission position, the optical signal 2 propagated through the core layer 100 is optically path-changed so as to enter the light receiving element 129 by the mirror 10F. Further, the optical path 2 of the optical signal 2 propagated through the cladding layer 101 is changed by the mirror 10G so as to enter the light receiver 14B.

  When transmitting the optical signal 2 from the first optical module 12A to the second optical module 12B, an abnormality has occurred simply by monitoring whether or not the optical signal 2 can be received by the second optical module 12B on the receiving side. Even if it can be found, it cannot be specified whether the generation location is the first optical module 12A, the optical waveguide 10C, or the second optical module 12B.

  In the second embodiment, an abnormality in each part of the optical path is determined by providing a plurality of light receivers 14A and 14B and receiving inspection light from the optical path conversion surface.

(Inspection of optoelectronic circuit board)
FIG. 8 is a flowchart illustrating the inspection of the first optical module, the optical waveguide, and the second optical module in the second embodiment.

  First, as shown in FIG. 7, the operator places the light receiver 14A at the position of the opening 10b of the second substrate 10B on the light incident position side, and the opening 10b of the second substrate 10B on the light emission position side. The light receiver 14B is disposed at the position (S11).

  Next, the operator operates the operation unit 21 of the inspection apparatus 20 to perform initial setting, and enters a standby state in which a drive voltage can be supplied from the power supply unit 24 (S12).

  Next, the operator connects the ground wire to the inspection ground 1C and brings the voltage detection probe 27 into contact with the inspection terminal 1A (S13). In a situation where the light emitting element 125 operates normally without any abnormality, a driving voltage is supplied from the inspection terminal 1A to the light emitting element 125 of the first optical module 12A by bringing the voltage detection probe 27 into contact therewith. The light emitting element 125 emits light based on the driving voltage and emits an optical signal 2 as inspection light.

  The operator monitors the screen display of the display unit 23 and confirms whether or not the output of the light receiver 14A has changed. When it is confirmed by the screen display that the light intensity exceeding the threshold and the ON / OFF signal corresponding to the input signal are obtained (S14: Yes), the light emitting element 125 of the first optical module 12A is operating normally. Judge that.

  Further, the operator monitors the screen display of the display unit 23 and confirms whether or not the output of the light receiver 14B has changed. When it is confirmed on the screen display that the light intensity exceeding the threshold and the ON / OFF signal corresponding to the input signal are obtained (S15: Yes), the optical signal 2 is normal through the cladding layer 101 of the optical waveguide 10C. It is judged that it is propagated to.

  Further, the operator monitors the screen display of the display unit 23 and confirms whether or not an output based on light reception of the light receiving element 129 is obtained from the signal line 28. If it is confirmed by the screen display that the light intensity equal to or higher than the threshold and the ON / OFF signal corresponding to the input signal are obtained (S16: Yes), it is determined that the light receiving element 129 is operating normally. Thereby, it is determined that the transmission / reception of the optical signal 2 from the first optical module 12A to the second optical module 12B is operating normally (S17).

  On the other hand, when it is confirmed that the light intensity exceeding the threshold value or the ON / OFF signal corresponding to the input signal is not obtained from the light receiver 14A (S14: No), the light emitting element 125 of the first optical module 12A is It is determined that a light emission failure has occurred.

  When it is confirmed that the light intensity exceeding the threshold value or the ON / OFF signal corresponding to the input signal is not obtained from the light receiver 14B (S15: No), the light emitting element 125 of the first optical module 12A is Although it is normal, it is determined that some damage has occurred in the optical waveguide 10C.

  When it is confirmed that the output based on the light reception of the light receiving element 129 is not obtained (S16: No), the light emitting element 125 of the first optical module 12A is normal and the optical waveguide 10C is also normal. It is determined that the light receiving element 129 of the two-optical module 12B has a light reception failure.

[Third embodiment]
(Configuration of optoelectronic circuit board)
FIG. 9 is a schematic configuration diagram of an optoelectronic circuit board according to the third embodiment of the present invention.

  The third embodiment is different from the second embodiment in the configuration in which the size of the mirrors 10D and 10E provided as the optical path conversion surface in the optical waveguide 10C is smaller than the size of the core layer 100.

  In the case of the substrate 10 having such an optical waveguide 10 </ b> C, the optical signal 2 emitted from the light emitting element 125 and subjected to optical path conversion by the mirror 10 </ b> D provided at the light incident position enters the core layer 100. The optical signal 2 incident on the core layer 100 propagates while diffusing. A part of the optical signal 2 is optically path-converted by the mirror 10F provided at the light incident / incident position and enters the light receiving element 129, and a component not optical path-reflected is reflected by the mirror 10G at the subsequent stage and enters the light receiver 14B.

  As described above, a part of light with less noise that has propagated through the core layer 100 may be used as inspection light.

[Other embodiments]
The present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the invention. In addition, the constituent elements of the respective embodiments can be arbitrarily combined without departing from the spirit of the present invention.

  For example, the inclined surface 103A of the optical waveguide described in FIGS. 4A and 4B is not limited to 45 degrees. Further, the light reflecting film formed as the mirror 10D is not limited to the metal film, and a dielectric multilayer film having wavelength selectivity may be formed.

  In addition, the first optical module 12A and the second optical module 12B have been described as bidirectional optical modules each having both the light emitting element 125 and the light receiving element 129. However, the first optical module 12A and the second optical module 12B have only the light emitting element 125 or only the light receiving element 129. As the unidirectional optical module, optical communication via the optical waveguide 10C may be performed.

FIG. 1 shows a schematic configuration of an optoelectronic circuit board according to a first embodiment of the present invention, wherein (a) is a perspective view of the optoelectronic circuit board, and (b) is an optoelectronic circuit in the AA portion of (a). The longitudinal cross-sectional view of the center part of a board | substrate, (c) is a cross-sectional view of the optoelectronic circuit board in the BB part of (a). FIG. 2 is a partial cross-sectional view of the first optical module portion obtained by cutting the optoelectronic circuit board at the AA portion in FIG. FIG. 3 is a partial cross-sectional view of the second optical module section obtained by cutting the optoelectronic circuit board at the AA section in FIG. 4A (a) to 4 (d) are diagrams illustrating a process of providing a mirror as an optical path conversion surface in an optical waveguide. FIGS. 4B (e) to 4 (g) are diagrams showing a process of providing a mirror as an optical path conversion surface in the optical waveguide. FIGS. 5A and 5B are diagrams showing a process of integrating the optical waveguide with the first substrate and the second substrate. FIG. 6 is a flowchart illustrating the inspection of the first optical module according to the first embodiment. FIG. 7 is a schematic configuration diagram of an optoelectronic circuit board and an inspection apparatus according to the second embodiment of the present invention. FIG. 8 is a flowchart illustrating the inspection of the first optical module, the optical waveguide, and the second optical module in the second embodiment. FIG. 9 is a schematic configuration diagram of an optoelectronic circuit board according to the third embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Optoelectronic circuit board, 1A, 1B, 1D, 1E ... Inspection terminal, 1C ... Inspection ground, 2 ... Optical signal, 10 ... Substrate, 10A ... First substrate, 10B ... Second substrate, 10a, 10b ... Opening Part, 10C ... optical waveguide, 10D, 10F, 10G ... mirror, 10E ... light transmitting resin, 12A ... first optical module, 12B ... second optical module, 14, 14A, 14B ... light receiver, 20 ... inspection device, DESCRIPTION OF SYMBOLS 21 ... Operation part, 22,22A, 22B ... Signal conversion part, 23 ... Display part, 24 ... Power supply part, 25 ... Control part, 26 ... Power supply line, 27 ... Electric detection probe, 28 ... Signal line, 100 ... Core layer , 101 ... cladding layer, 103 ... groove, 103A ... inclined surface, 104 ... photoresist, 105 ... opening, 110A ... terminal, 120 ... terminal, 121 ... solder ball, 122 ... support substrate, 123 ... wire, 12 ... terminal, 125 ... light emitting element, 126 ... controller, 127 ... terminal, 128 ... sealing resin, 129 ... light-receiving element

Claims (9)

A first substrate having a mounting surface on which an optical module having a light emitting element is mounted;
A core provided on a surface opposite to the mounting surface of the first substrate and having a core for propagating light emitted from the light emitting element and a clad covering the core; An optical waveguide provided with an optical path conversion surface;
A second substrate provided on a surface of the optical waveguide opposite to the surface on which the first substrate is provided, and provided with a light emitting portion that emits light emitted from the light emitting element via the optical waveguide; An optoelectronic circuit board.   The optoelectronic circuit board according to claim 1, wherein the light emitting portion is an opening provided in the second substrate corresponding to the light incident position.   The optoelectronic circuit board according to claim 1, wherein the light emitting portion is an opening provided in the second substrate corresponding to the light emitting position.   The optoelectronic circuit board according to claim 1, wherein the optical path changing surface has a reflecting surface smaller than a diameter of light emitted from the light emitting element. The optical path conversion surface is a first optical path conversion surface provided so that the light is incident on the core and the clad at the light incident position;
2. The optoelectronic circuit board according to claim 1, further comprising: a second optical path conversion surface configured to perform optical path conversion of the light reflected by the first optical path conversion surface and propagated through the cladding and to emit the light from the light emitting unit. The optical path conversion surface is a first optical path conversion surface provided at a size smaller than the size of the core at the light incident position;
The light emitting position is provided with a size smaller than the size of the core, and a part of the light reflected by the first optical path conversion surface and propagated through the core is optically converted and emitted from the light emitting unit. The optoelectronic circuit board according to claim 1, further comprising a second optical path conversion surface. A first substrate having a mounting surface on which an optical module having a light emitting element is mounted; an optical waveguide provided on a surface of the first substrate opposite to the mounting surface; and the first substrate of the optical waveguide An optoelectronic circuit board having a second substrate provided on a surface opposite to the surface provided with
A power supply unit that applies a driving voltage to the light emitting element of the optical module mounted on the mounting surface of the first substrate;
A light-receiving unit that receives inspection light emitted from the light-emitting element based on application of the drive voltage via the first substrate, the optical waveguide, and the second substrate;
An inspection apparatus for an optoelectronic circuit board, comprising: a signal detection unit that outputs a detection signal based on reception of the inspection light.   The optoelectronic circuit board inspection apparatus according to claim 7, wherein the light receiving unit is provided so as to be positioned in an opening provided in the first and second substrates in accordance with a light incident position on the optical waveguide.   The light receiving portion includes a first light receiving portion provided to be positioned in a first opening provided in the second substrate according to a light incident position on the optical waveguide, and light emission from the optical waveguide. The inspection apparatus for an optoelectronic circuit board according to claim 7, further comprising: a second light receiving portion provided so as to be positioned in a second opening provided in the second substrate according to a position.

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