JP2016099467A - Optical module and optical cable - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical module and an optical cable that are capable of downsizing.SOLUTION: An optical module includes: an optical element 3 that emits or receives light; an electronic component 4 that is electrically connected to the optical element 3; and a substrate 2 in which the electronic component 4 is mounted on a mounting surface 2a thereof. In the electronic component 4, the optical element 3 is mounted on an upper surface 4a which is an opposite side to a lower surface 4b opposed to the mounting surface 2a. Moreover, the optical module is provided on both ends of an optical fiber in an optical cable.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an optical module having a light emitting element or a light receiving element, and an optical cable having the optical module at both ends of an optical fiber.

  Conventionally, as an optical module including a cylindrical member into which a ferrule attached to the tip of an optical fiber is fitted and an optical element optically coupled to the optical fiber, an optical fiber socket described in Patent Document 1 is provided. Are known.

  The optical fiber socket includes a circuit board on which a wiring pattern is formed, an optical element (photoelectric conversion element) and an electrical component mounted on an element mounting surface of the circuit board, and a sleeve block receiving member that receives the sleeve block. Have. The sleeve block receiving member is made of a resin integrally formed with the circuit board, and a cylindrical concave cavity for inserting the sleeve block is formed. A cylindrical ferrule fitted on the tip of the optical fiber is fitted and inserted into the sleeve block.

  The sleeve block includes a cylindrical sleeve, a condensing lens, and a pair of fitting protrusions formed on the end surface of the sleeve. On the other hand, the fitting member is formed with two fitting holes into which the pair of fitting projections of the sleeve block are respectively fitted. The sleeve block is positioned relative to the circuit block by inserting the lower portion of the sleeve into the concave cavity of the receiving member and inserting the fitting protrusion into the fitting hole of the receiving member.

  When the optical element is a light emitting element, the optical element receives a current supplied from an electric component mounted on the circuit board, converts an electric signal generated by the current into an optical signal, and radiates the optical signal. The light emitted from the optical element is collected by the condenser lens and enters the optical fiber held by the ferrule. When the optical element is a light receiving element, the light emitted from the optical fiber is collected by the condenser lens and enters the optical element. The optical element converts an optical signal from the light into an electrical signal and outputs the electrical signal to an electrical component mounted on the circuit board, and the electrical component amplifies the electrical signal and outputs it to the outside.

  The axial end surface of the sleeve block is in contact with the element mounting surface of the circuit board as shown in FIG. And an optical element and an electrical component are accommodated in the inside of the hole formed in the center part of a sleeve block.

JP 2012-242658 A

  Since optical communication using such an optical module is superior in high-speed transmission and noise resistance compared to communication using electrical signals, its application is expanding in various fields in recent years. However, depending on the application, it may be necessary to significantly reduce the size of the optical module. Examples of such applications include communication between an operation unit (keyboard mounting unit) and a display unit (display mounting unit) of a foldable or slide type mobile phone.

  In the optical fiber socket described in Patent Document 1, the optical element and the electrical component are accommodated in the hole formed in the central portion of the sleeve block as described above. The optical element and the electrical component are accommodated in the hole. Securing a space for housing the optical module sometimes becomes an obstacle to downsizing the optical module.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an optical module that can be miniaturized and an optical cable using the optical module.

  In order to solve the above problems, the present invention provides an optical element that emits or receives light, an electronic component that is electrically connected to the optical element, and a substrate on which the electronic component is mounted on a mounting surface. And an optical module in which the optical element is mounted on the upper surface opposite to the lower surface facing the mounting surface of the electronic component.

  In order to solve the above problems, the present invention has an optical fiber and a pair of optical modules provided at both ends of the optical fiber, and the optical module emits or receives light. An electronic component electrically connected to the optical element; and a substrate on which the electronic component is mounted on a mounting surface; and an upper surface opposite to the lower surface of the electronic component facing the mounting surface. An optical cable is provided in which the optical element is mounted, the optical element of one of the pair of optical modules is a light emitting element, and the optical element of the other optical module is a light receiving element.

  According to the present invention, it is possible to reduce the size of the optical module and the optical cable.

1 is a perspective view showing an entire optical module according to a first embodiment of the present invention. It is a disassembled perspective view which abbreviate | omits illustration of the frame of an optical module, and shows the inside. It is the perspective view which looked at the sleeve of an optical module from the direction different from FIG.1 and FIG.2. It is a front view which shows the mounting surface side of a board | substrate with an optical element and an electronic component. It is a rear view which shows the non-mounting surface side of a board | substrate. It is a perspective view which expands and shows an optical element and an electronic component. It is sectional drawing which shows the ferrule and optical fiber which were inserted in the holding hole of an optical module and a sleeve. (A)-(c) is explanatory drawing which shows an example of the mounting process of the optical element in the manufacturing process of an optical module. It is a perspective view which shows the optical element and electronic component which concern on the 2nd Embodiment of this invention. It is a block diagram which shows the optical cable which concerns on the 3rd Embodiment of this invention.

[First Embodiment]
An optical module according to a first embodiment of the present invention will be described with reference to FIGS.

  FIG. 1 is a perspective view showing the entire optical module. FIG. 2 is an exploded perspective view showing the inside of the optical module without showing the frame. FIG. 3 is a perspective view of the sleeve of the optical module as seen from a direction different from FIGS. 1 and 2.

  The optical module 100 includes a frame 1, a substrate 2 partially accommodated in the frame 1, an optical element 3, an electronic component 4 electrically connected to the optical element 3, an optical element 3, and an optical element And a sleeve 5 as a holding member for holding the optical fiber to be coupled.

  The frame body 1 is formed with a circular insertion hole 1a through which the sleeve 5 is inserted. The sleeve 5 inserted through the insertion hole 1 a has an axial end surface 5 a (shown in FIG. 3) abutted against the substrate 2.

  The sleeve 5 has a cylindrical shape in which a holding hole 50 for holding an optical fiber is formed at the center thereof. As shown in FIG. 3, a pair of protrusions 51 and 52 that extend in parallel with the central axis 50 a of the holding hole 50 are provided on the axial end surface 5 a of the sleeve 5. The sleeve 5 is fixed to the mounting surface 2 a side of the substrate 2 so that the central axis 50 a intersects the substrate 2. In the present embodiment, the sleeve 5 is fixed to the frame 1 so that the central axis 50 a of the holding hole 50 is perpendicular to the substrate 2.

  A wiring pattern made of a highly conductive metal such as a copper foil is formed on both surfaces of a substrate 20 made of a plate-like insulator having electrical insulation properties such as PI (polyimide) and glass epoxy. Yes. In the present embodiment, the optical element 3 and the electronic component 4 are disposed on one surface side of the substrate 2, and no component is mounted on the rear surface. Hereinafter, the surface on which the optical element 3 and the electronic component 4 are arranged is referred to as a mounting surface 2a, and the back surface is referred to as a non-mounting surface 2b.

  The substrate 2 has a rectangular shape, and one end portion in the longitudinal direction is formed as a connector portion 200. A wiring pattern is formed on the non-mounting surface 2 b of the connector portion 200 so as to extend in a comb shape along the longitudinal direction of the substrate 2. Details of the wiring pattern on the non-mounting surface 2b will be described later.

  In addition, as shown in FIG. 2, fitting holes 201 and 202 into which the pair of protrusions 51 and 52 of the sleeve 5 are fitted are formed in the substrate 2. The sleeve 5 is positioned with respect to the substrate 2 by fitting the pair of protrusions 51 and 52 into the fitting holes 201 and 202.

  The optical element 3 is an element that emits or receives light. More specifically, the optical element 3 is a light emitting element that converts an electrical signal into an optical signal and outputs it, or a light receiving element that converts an optical signal into an electrical signal and outputs it. As the light emitting element, for example, VCSEL (Vertical Cavity Surface Emitting LASER (Vertical Cavity Surface Emitting Laser)) can be used, and as the light receiving element, for example, a photodiode can be used.

  When the optical element 3 is a light emitting element, the electronic component 4 is a drive element that supplies a current corresponding to an electrical signal transmitted via the connector unit 200 to the optical element 3. When the optical element 3 is a light receiving element, the electronic component 4 is an amplifying element that amplifies and outputs an electric signal from the optical element 3. In the following description, the case where the optical element 3 is a VCSEL and the electronic component 4 is a drive element will be described as an example.

  The electronic component 4 is mounted on the mounting surface 2 a of the substrate 2. The optical element 3 is mounted on the upper surface 4 a of the electronic component 4, where the surface of the electronic component 4 facing the mounting surface 2 a is the lower surface 4 b and the opposite surface is the upper surface 4 a. That is, the optical element 3 is mounted so as to be stacked on the electronic component 4 with the electronic component 4 sandwiched between the optical element 3 and the substrate 2. In the present embodiment, the words “upper” or “lower” are used for clarification of the explanation, but are not intended to limit the upper or lower side in the vertical direction in the usage state of the optical module 100 or the like. Absent.

  When the optical module 100 is viewed from the central axis direction of the sleeve 5 (the direction of the central axis 50 a of the holding hole 50), the optical element 3 and the electronic component 4 are disposed on the inner side of the peripheral edge of the sleeve 5. In other words, the optical element 3 and the electronic component 4 are arranged in a virtual circle when the outer peripheral surface 5b of the sleeve 5 is projected onto the mounting surface 2a of the substrate 2 along the direction of the central axis 50a.

  FIG. 4 is a front view showing the mounting surface 2 a side of the substrate 2 together with the optical element 3 and the electronic component 4. FIG. 5 is a rear view showing the non-mounting surface 2 b side of the substrate 2. FIG. 6 is an enlarged perspective view showing the optical element 3 and the electronic component 4. In FIG. 4, a virtual circle 5b ′ obtained by projecting the outer peripheral surface 5b of the sleeve 5 onto the mounting surface 2a of the substrate 2 along the direction of the central axis 50a is indicated by a two-dot chain line.

  Each of the optical element 3 and the electronic component 4 has a rectangular parallelepiped shape, and a plurality of electrodes are formed on one plane. Hereinafter, a plane on which the electrode in the optical element 3 is formed is referred to as an electrode forming surface 30. Similarly, a plane on which the electrodes in the electronic component 4 are formed is referred to as an electrode forming surface 40.

  In the present embodiment, as shown in FIG. 6, eight electrodes (first to eighth electrodes 41 to 48) are formed on the electrode formation surface 40 of the electronic component 4. Among the eight electrodes, the first to fourth electrodes 41 to 44 and the fifth to eighth electrodes 45 to 48 are arranged in two rows along the longitudinal direction of the electrode forming surface 40. That is, the first electrode row 40 a made up of the first to fourth electrodes 41 to 44 and the second electrode row 40 b made up of the fifth to eighth electrodes 45 to 48 along the longitudinal direction of the electrode formation surface 40. Are provided parallel to each other.

  The electronic component 4 is mounted on the substrate 2 such that the electrode forming surface 40 does not face the mounting surface 2a. That is, the electronic component 4 is mounted on the substrate 2 such that the electrode forming surface 40 is the upper surface 4a. The optical element 3 is arranged such that the electrode forming surface 30 faces the same side as the electrode forming surface 40 of the electronic component 4 (the side opposite to the substrate 2).

  The optical element 3 is mounted between the first electrode row 40 a and the second electrode row 40 b on the electrode formation surface 40 of the electronic component 4. First to third electrodes 31 to 33 are formed on the electrode forming surface 30 of the optical element 3. However, among these, the third electrode 33 is a dummy electrode that is not electrically connected. In addition, an opening 30 a for emitting light in a direction perpendicular to the substrate 2 is formed in the electrode forming surface 30.

  The first electrode 31 of the optical element 3 is electrically connected to the first electrode 41 of the electronic component 4 by a bonding wire 61. Further, the second electrode 32 of the optical element 3 is electrically connected to the eighth electrode 48 of the electronic component 4 by a bonding wire 68. The optical element 3 emits light upon receiving a drive current from the first and eighth electrodes 41 and 48 of the electronic component 4 via the bonding wires 61 and 68.

  4 and 5, when the wiring pattern on the mounting surface 2a side of the substrate 2 is a mounting surface wiring pattern 21 and the wiring pattern on the non-mounting surface 2b side is a non-mounting surface wiring pattern 22, the mounting surface wiring pattern 21 includes first to sixth conductor portions 211 to 216, and the non-mounting surface wiring pattern 22 includes first to sixth conductor portions 221 to 226.

  The first conductor portion 211 of the mounting surface wiring pattern 21 and the first conductor portion 221 of the non-mounting surface wiring pattern 22 are electrically connected by a via 23 that penetrates the base material 20. Similarly, the second to sixth conductor portions 212 to 216 of the mounting surface wiring pattern 21 and the second to sixth conductor portions 226 of the non-mounting surface wiring pattern 22 are electrically connected by the vias 23, respectively. ing.

  Further, as shown in FIG. 4, the first to third conductor portions 211 to 213 of the mounting surface wiring pattern 21 are bonded to the second to fourth electrodes 42 to 44 of the electronic component 4 by bonding wires 62 to 64. Each is electrically connected. Similarly, the fourth to sixth conductor portions 214 to 216 of the mounting surface wiring pattern 21 are electrically connected to the fifth to seventh electrodes 45 to 47 of the electronic component 4 by bonding wires 65 to 67, respectively. ing. In FIG. 6, the bonding wires 62 to 67 are not shown.

  The first to sixth conductor portions 221 to 226 of the non-mounting surface wiring pattern 22 extend in parallel to each other along the longitudinal direction of the substrate 2 in the connector portion 200. When the connector part 200 of the board 2 is fitted into the mating connector, the terminals of the mating connector and the first to sixth conductor parts 221 to 226 are electrically connected to each other. Then, a power supply and a signal can be exchanged between the optical module 100 and the motherboard on which the counterpart connector is mounted.

  FIG. 7 shows a cross section of the optical module 100 and the ferrule 7 and the optical fiber 8 inserted into the holding hole 50 of the sleeve 5 cut along a cross section perpendicular to the longitudinal direction of the substrate 2 and including the central axis 50a of the holding hole 50. FIG.

  The ferrule 7 is a cylindrical member attached to the end of the optical fiber 8, and the optical fiber 8 is inserted through the shaft hole 70.

  The sleeve 5 supports the optical fiber 8 by inserting the ferrule 7 into the holding hole 50. That is, the sleeve 5 supports the optical fiber 8 through the ferrule 7. The holding hole 50 includes a large diameter portion 501 that can accommodate the ferrule 7 and a small diameter portion 502 having an inner diameter smaller than the outer diameter of the ferrule 7. The inner diameter of the large diameter portion 501 is substantially the same as the outer diameter of the ferrule 7. By inserting the ferrule 7 into the large diameter portion 501, the sleeve 5 and the optical fiber 8 are arranged coaxially. . The ferrule 7 may be adhered to the sleeve 5, but may be detachable from the sleeve 5.

  A pair of protrusions 51, 52 provided on the axial end surface 5 a of the sleeve 5 pass through the fitting holes 201, 202 of the substrate 2, and further, the fitting holes 101, 102 formed in the back plate 10 of the frame body 1. Is inserted. The non-mounting surface wiring pattern 22 on the non-mounting surface 2 b of the substrate 2 is in contact with the back plate 10 of the frame 1.

  The ferrule 7 is abutted against a step surface 503 a of a step 503 formed between the large diameter portion 501 and the small diameter portion 502. That is, in the ferrule 7, the axial end surface 7 a facing the mounting surface 2 a of the substrate 2 contacts the stepped surface 503 a of the sleeve 5, and the positions of the ferrule 7 and the optical fiber 8 in the axial direction with respect to the substrate 2 are determined. . That is, the stepped portion 503 functions as a positioning portion that defines the position of the optical fiber 8 inserted into the holding hole 50 with respect to the substrate 2.

  In FIG. 7, the light flux emitted from the light emitting unit 300 of the optical element 3 is indicated by reference numeral 300a. This light beam 300 a is incident on the core 81 covered with the cladding 80 of the optical fiber 8. When the optical element 3 is a light receiving element, light emitted from the core 81 of the optical fiber 8 enters the light receiving portion of the optical element 3. In this way, the optical element 3 is optically coupled to the optical fiber 8.

  FIGS. 8A to 8C are explanatory views illustrating an example of the mounting process of the optical element 3 in the manufacturing process of the optical module 100.

  In the mounting process of the optical element 3, as shown in FIGS. 8A and 8B, the first electrode array 40a and the second electrode of the electronic component 4 mounted on the substrate 2 in advance with the electrode forming surface 40 as the upper surface 4a. An adhesive G for fixing the optical element 3 is placed between the row 40b. The adhesive G is spread enough when the optical element 3 is mounted, and does not cover the first electrode row 40a or the second electrode row 40b of the electronic component 4, and is sufficient to fix the optical element 3. Is discharged from the nozzle 91.

  Next, as shown in FIG. 8C, the optical element 3 is held by the mounting head 92 of the mounting machine, and the surface opposite to the electrode forming surface 30 is the upper surface 4a (electrode forming surface 40) of the electronic component 4. The optical element 3 is mounted on the electronic component 4 so as to face each other. As long as the mounting head 92 of the mounting machine can hold the optical element 3 and can move from the component supply unit onto the electronic component 4, the mounting head 92 is not limited to the one that holds the optical element 3, and for example, adsorbs the optical element 3. You may do.

  After the adhesive G is solidified and the optical element 3 is fixed to the upper surface 4a of the electronic component 4, the first and second electrodes 31 and 32 of the optical element 3 and the electronic component 4 are bonded by the bonding wires 61 and 68. The first and eighth electrodes 41 and 48 are connected. In addition, the second to fourth electrodes 42 to 44 of the electronic component 4, the first to third conductor portions 211 to 213 of the mounting surface wiring pattern 21, and the fifth to seventh electrodes 45 to 47 of the electronic component 4. The fourth to sixth conductor portions 214 to 216 of the mounting surface wiring pattern 21 are connected by bonding wires 62 to 67, respectively. Thereafter, the substrate 2 is further assembled to the frame body 1 and the sleeve 5 is fixed to the frame body 1 to obtain the optical module 100.

(Operation and effect of the first embodiment)
According to the first embodiment of the present invention described above, the following operations and effects can be obtained.

(1) Since the optical element 3 is mounted on the upper surface 4 a of the electronic component 4, a space for arranging the optical element 3 on the mounting surface 2 a of the substrate 2 is unnecessary. Thereby, the board | substrate 2 can be reduced in size and the optical module 100 can also be reduced in size.

(2) Since the electronic component 4 is mounted on the substrate 2 with the electrode forming surface 40 as the upper surface 4a, the first and eighth electrodes 41 and 48 of the electronic component 4 and the first and second electrodes of the optical element 3 are mounted. 31 and 32 can be directly connected by bonding wires 61 and 68.

(3) The sleeve 5 is disposed on the mounting surface 2 a side of the substrate 2, and the optical element 3 and the electronic component 4 are located on the inner side of the peripheral portion of the sleeve 5 when viewed from the central axis 50 a of the sleeve 5. Has been placed. That is, the optical element 3 and the electronic component 4 are arranged inside a virtual circle 5b ′ (shown in FIG. 4) obtained by projecting the outer peripheral surface 5b of the sleeve 5 onto the mounting surface 2a of the substrate 2 along the direction of the central axis 50a. Therefore, it is not necessary to secure an arrangement space for the optical element 3 and the electronic component 4 outside the arrangement area of the sleeve 5, and the optical module 100 can be easily downsized.

(4) In the sleeve 5, a step 503 is formed between the large diameter portion 501 and the small diameter portion 502, and the position of the optical fiber 8 with respect to the substrate 2 is defined by the step 503. The distance from the end of the optical fiber 8 can be maintained at an appropriate distance, and the optical element 3 and the optical fiber 8 can be reliably optically coupled.

(5) Both the optical element 3 and the electronic component 4 are mounted on the mounting surface 2 a side of the substrate 2, and no component is mounted on the non-mounting surface 2 b of the substrate 2. That is, since it is not necessary to mount components on both sides of the substrate 2, for example, it is not necessary to turn the substrate 2 upside down in the component mounting process, and component mounting is facilitated. Moreover, the non-mounting surface 2b of the board | substrate 2 can be attached to the back plate 10 of the frame 1, and can be assembled | attached, and the thickness of the frame 1 can be made thin. Thereby, the optical module 100 can be further downsized.

[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 9 is a perspective view showing the optical element 3 and the electronic component 4 according to the second embodiment. The optical module according to the present embodiment is the same as the optical module 100 according to the first embodiment, except that the configuration of the optical element 3 and the electronic component 4 and the wiring pattern in the periphery thereof is different. Illustration and description of this common part are omitted. Moreover, in FIG. 9, the electrode etc. of the part hidden in the optical element 3 and the electronic component 4 are shown with the broken line.

  In the first embodiment, the case where the electronic component 4 is mounted on the substrate 2 with the electrode formation surface 40 as the upper surface 4a has been described. However, in the second embodiment, the electronic component 4 has the electrode formation surface 40 on the lower surface. It is mounted on the substrate 2 as 4b. That is, in the second embodiment, the electrode forming surface 40 faces the mounting surface 2a of the substrate 2, and the plane 400 opposite to the electrode forming surface 40 is the upper surface 4a, and the optical element 3 is mounted on the upper surface 4a. ing.

  In the first embodiment, the second to seventh electrodes 42 to 47 of the electronic component 4 are connected to the first to sixth conductor portions 211 to 216 in the mounting surface wiring pattern 21 of the substrate 2. However, in this embodiment, the mounting surface wiring pattern 21 includes first to eighth conductor portions 211 to 218, and the first to eighth electrodes 41 to 48 of the electronic component 4 are connected. Are directly connected to the first to eighth conductor portions 211 to 218 without using a bonding wire. That is, the electronic component 4 is flip-chip mounted on the substrate 2.

  The first electrode 31 of the optical element 3 is connected to the first conductor portion 211 connected to the first electrode 41 of the electronic component 4 by a bonding wire 691. Further, the second electrode 32 of the optical element 3 is connected to an eighth conductor portion 218 connected to the second electrode 42 of the electronic component 4 by a bonding wire 692. That is, in the present embodiment, the first and eighth electrodes 41 and 48 of the electronic component 4 and the first and second electrodes 31 and 32 of the optical element 3 are connected to the mounting surface wiring pattern 21 and the bonding of the substrate 2. The wires 691 and 692 are electrically connected.

  The second to seventh conductor portions 212 to 217 of the mounting surface wiring pattern 21 are connected to the wiring patterns (not shown) on the non-mounting surface 2b of the substrate 2 by the vias 23 to supply power to the electronic component 4, It functions as a signal transmission medium.

  Also in the present embodiment, the optical element 3 is mounted on the upper surface 4a of the electronic component 4 by the same mounting process as in the first embodiment. The operations of the optical element 3 and the electronic component 4 are also the same as in the first embodiment.

  Also according to this embodiment, the same operations and effects as those of the first embodiment can be obtained. Moreover, since the electronic component 4 is flip-chip mounted on the substrate 2, the number of bonding wires can be reduced.

[Third Embodiment]
Next, a third embodiment of the present invention will be described with reference to FIG. FIG. 10 is a configuration diagram illustrating the optical cable 101 in which the optical module 100 according to the first embodiment is provided at both ends of the optical fiber.

  The optical cable 101 includes an optical fiber core 9 having the optical fiber 8 described in the first embodiment as an optical fiber, a ferrule 7, and a pair of optical modules 100 for transmission and reception. ing. In the following description, of the pair of optical modules 100, the transmission optical module 100 will be described as a transmission optical module 100A, and the reception optical module 100 will be described as a reception optical module 100B.

  The transmission optical module 100A and the reception optical module 100B are configured by mounting the optical element 3 and the electronic component 4 on the substrate 2, respectively. In the transmission optical module 100 </ b> A, the optical element 3 is a light emitting element, and the electronic component 4 is a drive element that supplies current to the optical element 3. In the receiving optical module 100B, the optical element 3 is a light receiving element, and the electronic component 4 is an amplifying element that amplifies and outputs an electric signal from the optical element 3.

  The optical fiber core 9 is configured by covering the optical fiber 8 (shown in FIG. 7) with a buffer layer made of, for example, silicon and an outer cover made of, for example, plastic.

  The optical cable 101 is used for transmission / reception of signals between information processing apparatuses, for example. In this case, the connector part 200 of the substrate 2 of the optical module for transmission 100A is fitted to the female connector provided on the motherboard of one information processing apparatus, and the receiving connector is connected to the female connector provided on the motherboard of the other information processing apparatus. The connector part 200 of the optical substrate 2 of the optical module 100B is fitted.

  The electronic component 4 of the transmission optical module 100A supplies current to the optical element 3 in accordance with a signal input via the connector portion 200 of the substrate 2 and causes the optical element 3 (light emitting element) to emit light. The light emitted from the optical element 3 propagates to the receiving optical module 100B using the optical fiber 8 as a medium, and is received by the optical element 3 (light receiving element) of the receiving optical module 100B. The output signal of the optical element 3 is amplified by the electronic component 4 of the receiving optical module 100B and output from the connector portion 200 of the substrate 2. As a result, signal transmission via the optical cable 101 is performed.

  According to this optical cable 101, since the optical fiber core wire 9 can be drawn out parallel to the mother board, bending of the optical fiber 8 between one mother board and the other mother board can be reduced. Thereby, loss of light due to bending of the optical fiber 8 can be suppressed.

  Instead of the optical module 100 according to the first embodiment, an optical cable may be configured by providing a second optical module at both ends of the optical fiber. That is, the electronic component 4 may be flip-chip mounted on the substrate 2.

(Summary of embodiment)
Next, the technical idea grasped from the embodiment described above will be described with reference to the reference numerals in the embodiment. However, each reference numeral in the following description does not limit the constituent elements in the claims to members or the like specifically shown in the embodiment.

[1] An optical element (3) for emitting or receiving light, an electronic component (4) electrically connected to the optical element (3), and the electronic component (4) mounted on a mounting surface (2a) The optical element (4) is mounted on the upper surface (4a) opposite to the lower surface (4b) facing the mounting surface (2a) of the electronic component (4). Optical module (100).

[2] The electronic component (4) is mounted on the substrate (2) such that the electrode formation surface (40) on which the electrodes (41 to 48) are formed becomes the upper surface (4a), and the electronic component ( The optical module according to [1], wherein the electrodes (41 to 48) of 4) and the electrodes (31, 32) of the optical element (3) are electrically connected by bonding wires (61 to 68). 100).

[3] The electronic component (4) is mounted on the substrate (3) such that the electrode forming surface (40) on which the electrodes (41 to 48) are formed becomes the lower surface (4b), and the electronic component ( 4) The electrodes (41 to 48) and the electrodes (31, 32) of the optical element (3) are electrically connected by the wiring pattern (21) and bonding wires (691, 692) of the substrate (3). The optical module (100) according to [1].

[4] The holding member further includes a cylindrical holding member (sleeve 5) in which a holding hole (50) for holding the optical fiber (8) optically coupled to the optical element (3) is formed. (5) is fixed to the mounting surface (2a) side of the substrate (2) so that the central axis (50a) of the holding hole (50) intersects the substrate (2), and the central axis ( 50a) When viewed from the direction, any one of [1] to [3] 3 in which the optical element (3) and the electronic component (4) are arranged on the inner side of the peripheral edge of the holding member (5). The optical module (100) according to any one of the above.

[5] The holding member (5) is formed with a positioning portion (503) for defining a position of the optical fiber (8) inserted into the holding hole (50) with respect to the substrate (2). 4] The optical module (100) according to [4].

[6] An optical element having an optical fiber (8) and a pair of optical modules (100) provided at both ends of the optical fiber (8), the optical module (100) emitting or receiving light (3), an electronic component (4) electrically connected to the optical element (3), and a substrate (3) on which the electronic component (4) is mounted on a mounting surface. The optical element (3) is mounted on the upper surface (4a) opposite to the lower surface (4b) facing the mounting surface (2a) in 4), and one of the pair of optical modules (100) The optical cable (101), wherein the optical element (3) of the module (100) is a light emitting element and the optical element (3) of the other optical module is a light receiving element.

  While the embodiments of the present invention have been described above, the embodiments described above do not limit the invention according to the claims. In addition, it should be noted that not all the combinations of features described in the embodiments are essential to the means for solving the problems of the invention.

DESCRIPTION OF SYMBOLS 2 ... Board | substrate 2a ... Mounting surface 2b ... Non-mounting surface 3 ... Optical element 31-33 ... 1st thru | or 3rd electrode 4 ... Electronic component 4a ... Upper surface 4b ... Lower surface 41-48 ... 1st thru | or 8th electrode 5 ... Sleeve (holding member)
5a ... axial end face 50a ... central axes 61-68, 691, 692 ... bonding wire 8 ... optical fiber 100 ... optical module 101 ... optical cable

Claims (6)

An optical element that emits or receives light; and
An electronic component electrically connected to the optical element;
A board on which the electronic component is mounted on a mounting surface;
An optical module in which the optical element is mounted on an upper surface opposite to a lower surface facing the mounting surface of the electronic component. The electronic component is mounted on the substrate such that an electrode forming surface on which an electrode is formed is the upper surface,
The electrode of the electronic component and the electrode of the optical element are electrically connected by a bonding wire,
The optical module according to claim 1. The electronic component is mounted on the substrate such that an electrode forming surface on which an electrode is formed becomes the lower surface,
The electrode of the electronic component and the electrode of the optical element are electrically connected by a wiring pattern and a bonding wire of the substrate,
The optical module according to claim 1. A cylindrical holding member having a holding hole for holding an optical fiber optically coupled to the optical element;
The holding member is fixed to the mounting surface side of the substrate such that a central axis of the holding hole intersects the substrate,
When viewed from the central axis direction, the optical element and the electronic component are arranged on the inner side than the peripheral edge of the holding member,
The optical module according to claim 1. The holding member is formed with a positioning portion that defines a position of the optical fiber inserted into the holding hole with respect to the substrate.
The optical module according to claim 4. An optical fiber, and a pair of optical modules provided at both ends of the optical fiber;
The optical module includes an optical element that emits or receives light, an electronic component electrically connected to the optical element, and a substrate on which the electronic component is mounted on a mounting surface, and the mounting in the electronic component The optical element is mounted on the upper surface opposite to the lower surface facing the surface,
Of the pair of optical modules, the optical element of one optical module is a light emitting element, and the optical element of the other optical module is a light receiving element.
Optical cable.

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