JP2008147554A - Optical module and electric equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical module capable of coping with the miniaturization of an electric equipment, such as a portable telephone unit, and to provide the electric equipment having such an optical module. <P>SOLUTION: The optical module 5 has: a substrate 10; a laser diode 2 that is provided on a surface 10a of the substrate 10 and is a light-emitting element emitting a light signal; a drive element 3 that is provided on the surface 10a of the substrate 10, is connected to the laser diode 2 electrically, and drives the laser diode 2; and an electric connector 12 that supplies the drive power of the laser diode 2 and the drive element 3 and is provided on the rear 10b of the substrate 10. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an optical module used in an electric device such as a mobile phone, and an electronic device that houses the optical module in a housing.

  2. Description of the Related Art In recent years, electric devices such as mobile phones are required to process large amounts of data such as photographs and moving images at high speed, and large-capacity and high-speed data transmission is required in electric devices. In order to realize high-capacity and high-speed data transmission in an electric device, a flexible wiring board type optical module that performs photoelectric conversion using an optical element has been proposed.

More specifically, the flexible wiring board includes a film-like substrate having electrical wiring, a light emitting element that is mounted on the substrate and emits an optical signal, and a light receiving element that is mounted on the substrate and receives the optical signal. The device includes a film-like optical waveguide that is provided integrally with the substrate on the lower surface of the substrate and optically couples the light emitting device and the light receiving device. The flexible wiring board includes a card edge type electrical connector mounted on both ends of the substrate. When an electric signal is input to the driving element electrically connected to the light emitting element, the driving element controls light emission of the light emitting element, and the light emitting element emits an optical signal. Next, the emitted optical signal is propagated along the optical waveguide and is incident on the light receiving element through the optical waveguide. The incident optical signal is converted into an electric signal by the light receiving element, and the electric signal is amplified by the signal amplifying element electrically connected to the light receiving element and output to the outside (for example, Non-Patent Document 1).
“Mobile [CEATEC]”, [online], October 5, 2005, Tech On, [Search on December 1, 2006], Internet <URL: http://techon.nikkeibp.co.jp/ article / NEWS / 20051004/109288 / ＞

  However, since the conventional flexible substrate has the card edge type electrical connector as described above, the component mounting area of the substrate becomes large. Therefore, it is difficult to make the flexible substrate compact, and as a result, there is a problem that it is difficult to cope with the downsizing of electric devices (for example, mobile phones).

  Accordingly, the present invention has been made in view of the above-described problems, and provides an optical module that can cope with the miniaturization of an electric device (for example, a mobile phone), and an electric device including such an optical module. The purpose is to do.

  In order to achieve the above object, an invention according to claim 1 includes a substrate, an optical element provided on the surface of the substrate, and an electronic component provided on the surface of the substrate and electrically connected to the optical element. An optical module comprising an optical waveguide attached to a substrate and optically coupled to an optical element, and an electrical connector connected to an external device and for supplying driving power for the optical element and an electronic component. The electrical connector is provided on the back surface of the substrate.

  According to this configuration, compared with the above-described conventional optical module having a card edge type electrical connector, it is possible to reduce the component mounting area of the substrate in the optical module, and thus the optical module can be made compact. become. As a result, it is possible to provide an optical module that can cope with downsizing of an electric device (for example, a mobile phone).

  The invention described in claim 2 is the optical module according to claim 1, characterized in that the optical waveguide is formed of a polymer material. According to this configuration, it is possible to improve the flexibility and bendability of the optical waveguide, so that the optical waveguide can be easily deformed into a desired shape.

  The invention described in claim 3 is the optical module according to claim 2, wherein the polymer material is at least one selected from an epoxy resin, a silicon resin, an acrylic resin, and a polyimide resin. To do. According to this configuration, it is possible to form an optical waveguide excellent in flexibility and bendability by using an inexpensive and versatile material.

  Further, the optical module according to any one of claims 1 to 3 of the present invention has a characteristic that it can cope with downsizing of an electric device (for example, a mobile phone) in which the optical module is used. Therefore, as in the invention according to claim 4, the optical module according to any one of claims 1 to 3, wherein the optical element is a light emitting element that emits an optical signal to the optical waveguide. In addition, the electronic component is preferably used in an optical module that is a driving element for driving a light emitting element. According to a fifth aspect of the present invention, in the optical module according to any one of the first to third aspects, the optical element receives an optical signal via an optical waveguide, and the optical signal The electronic component is suitably used for an optical module that is a signal amplifying element for amplifying an electric signal.

  The invention according to claim 6 is capable of displacing the first casing for storing the first circuit board, the second casing for storing the second circuit board, and the first and second casings. A movable portion coupled to the first substrate, a first substrate, a light emitting element that emits an optical signal provided on the surface of the first substrate, and a surface that is provided on the surface of the first substrate and electrically connected to the light emitting element. A driving element for driving the light emitting element, and a first element provided on the back surface of the first substrate, connected to the first circuit board and supplying driving power for the light emitting element and the driving element. An optical connector for transmission that is housed in a first housing; a second substrate; and a surface of the second substrate. The optical signal is incident and the optical signal is electrically A light receiving element that converts the signal into a signal, and is provided on the surface of the second substrate, and is in electrical contact with the light receiving element. A signal amplifying element for amplifying the electric signal, and a second amplifying element provided on the back surface of the second substrate, connected to the second circuit board, and for supplying driving power to the light receiving element and the signal amplifying element. And an optical module for reception housed in a second housing, provided inside the movable part, and formed of a polymer material, and optically couples the light emitting element and the light receiving element. And an optical waveguide.

  According to the configuration, in the optical module for transmission, the first electrical connector for supplying the driving power of the light emitting element and the driving element is provided on the back surface of the first substrate, and in the optical module for reception, A second electrical connector for supplying driving power for the light receiving element and the signal amplifying element is provided on the back surface of the second substrate. Therefore, the component mounting area of the first and second substrates can be reduced as compared with the above-described conventional optical module having a card edge type electrical connector. As a result, it is possible to provide an electric device using a transmission / reception optical module that is compact and can accommodate downsizing of an electric device (for example, a mobile phone). Can be miniaturized.

  In addition, since the optical waveguide provided inside the movable portion is formed of a polymer material, the flexibility and bendability of the optical waveguide can be improved. Therefore, since the optical waveguide can be easily deformed into a desired shape, it is possible to flexibly cope with an operation in the movable part (for example, a folding operation or a folding operation of the mobile phone). In addition, the assembly of the electric equipment is facilitated.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to provide the optical module which can respond to size reduction of an electric equipment (for example, mobile phone).

  Hereinafter, a preferred embodiment of the present invention will be described. FIG. 1 is a top view for explaining an optical module according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view taken along line AA of FIG. As shown in FIGS. 1 and 2, this optical module includes a laser diode (hereinafter referred to as “LD”) 2 that is a light emitting element, and an LD 2 that is electrically connected to drive the LD 2. (That is, a light emitting unit 4 including a driving element 3 for controlling light emission of the light emitting element LD2 based on an externally input electric signal (hereinafter referred to as “first electric signal”)). The optical module 5 for transmission provided is provided. The optical module 1 includes a photodiode (Photo Diode: hereinafter referred to as “PD”) 6 that is a light receiving element, and an electrical signal (hereinafter referred to as “second”) that is electrically connected to the PD 6 and converted by the PD 6. And a receiving optical module 9 provided with a light receiving portion 8 including a signal amplifying element 7 for amplifying the signal. The optical module 1 also includes an optical waveguide 20 for optically coupling the LD 2 and the PD 6.

  As shown in FIG. 2, the optical module 5 includes a first substrate 10 (hereinafter referred to as “substrate 10”) formed of a material such as quartz glass or silicon single crystal, and is driven by the LD 2. The element 3 is connected to the electrode 11 formed on the substrate 10 and mounted on the surface 10 a of the substrate 10. Further, the LD 2 and the driving element 3 are provided on the back surface 10b of the substrate 10 through electric wiring (not shown) for transmitting a high-speed signal (for example, a signal of 400 Mbit / s or more) provided on the substrate 10. The first electric connector 12 (hereinafter referred to as “electric connector 12”) is electrically connected. That is, the electrical connector 12 is connected to a first external device (not shown) such as a circuit board, for example, and drive power is supplied from the first external device to the LD 2 and the drive element 3 via the electrical connector 12. Is configured to be supplied. The electrical connector 12 is for inputting a first electrical signal from the first external device to the drive element 3, and the first electrical signal is sent to the drive element 3 via the electrical connector 12. It is configured to be input.

  Similarly, the optical module 9 includes a second substrate 13 (hereinafter referred to as “substrate 13”) formed of a material such as quartz glass or silicon single crystal, and the PD 6 and the signal amplifying element 7 include , Connected to the electrode 14 formed on the substrate 13, mounted on the front surface 13 a of the substrate 13, and provided on the back surface 13 b of the substrate 13 through electrical wiring (not shown) provided on the substrate 13. 2 electrical connector 15 (hereinafter referred to as “electrical connector 15”). That is, the electrical connector 15 is connected to a second external device (not shown) such as a circuit board, and is driven from the second external device to the PD 6 and the signal amplifying element 7 via the electrical connector 15. The power is supplied. The electrical connector 15 is for outputting the second electrical signal amplified by the signal amplifying element 7 to the second external device, and the second electrical signal is transmitted via the electrical connector 15. It is configured to be output to the second external device.

  The electrodes 11 and 14 described above are made of, for example, a metal such as gold or aluminum. The LD 2 and the driving element 3 are electrically connected to the electrode 11 by soldering or the like, and the electrode 11 Is electrically connected. Similarly, the PD 6 and the signal amplifying element 7 are electrically connected to the electrode 14 by soldering or the like, and are also electrically connected via the electrode 14.

  As shown in FIGS. 1 and 2, an optical waveguide 20 for transmitting an optical signal between the light emitting unit 4 of the transmitting optical module 5 and the light receiving unit 8 of the receiving optical module 9. Is provided. As shown in FIG. 3, the optical waveguide 20 has a substantially circular cross section, and includes a high refractive index core layer 23 and a low refractive index clad layer 24 covering the core layer 23. Yes. The optical waveguide 20 is mounted on the substrate 10 by supporting one end portion 20 a of the optical waveguide 20 by a support member 21 provided on the substrate 10. Similarly, the other end portion 20 b of the optical waveguide 20 is supported by a support member 22 provided on the substrate 13, so that the optical waveguide 20 is mounted on the substrate 13. In the present embodiment, the optical waveguide 20 is aligned by the support members 21 and 22 described above so that the optical axis P of the core layer 23 coincides with the optical axes of the LD2 and PD6. . As described above, the optical waveguide 20 is attached to each of the substrates 10 and 13 and is configured to be optically coupled to the LD 2 and the PD 6 by the optical waveguide 20.

  Moreover, in this embodiment, it is set as the structure which forms the optical waveguide 20 with the polymeric material excellent in the softness | flexibility from a viewpoint that the softness | flexibility and bending property of the optical waveguide 20 are improved. As this polymer material, an inexpensive and versatile polymer material such as an epoxy resin, a silicon resin, an acrylic resin, or a polyimide resin is used.

  The LD 2 provided on the surface 10 a of the substrate 10 emits an optical signal having a predetermined wavelength (for example, an optical signal having a wavelength of 0.8 μm used in optical communication) toward the core layer 23 of the optical waveguide 20. To do. That is, the LD 2 converts the first electric signal input from the first external device through the electric connector 12 into the optical signal, and converts the optical signal to the core of the optical waveguide 20. The light is emitted toward the layer 23. As the LD 2, one corresponding to the emitted optical signal is used. In this embodiment, for example, a GaAlAs LD or an InGaAsP LD can be used.

  An optical signal emitted from the LD 2 is incident on the PD 6 provided on the surface 13 a of the substrate 13. That is, the PD 6 is configured to receive an optical signal emitted from the LD 2 and propagate through the core layer 23 of the optical waveguide 20 and convert the optical signal into an electric signal. As the PD 6, one corresponding to the received optical signal is used, and in the present embodiment, for example, a Si-based PD, an InGaAs-based PD, or an InGaAsP-based PD can be used.

  In the present embodiment, as the LD2 and PD6, a surface-emitting type LD2 (or light-receiving surface) having a predetermined area (expansion) that is relatively low cost and has a predetermined area (expansion) is provided. Alternatively, a surface-receiving PD6) can be used.

  As shown in FIG. 2, the transmission optical module 5 is covered with a sealing body 30 so that the connection portion 12a of the electrical connector 12 is exposed. Similarly, the receiving optical module 9 is covered with the sealing body 31 so that the connection portion 15a of the electrical connector 15 is exposed. As a material for forming the sealing bodies 30 and 31, an optical path portion between the LD 2 and the optical waveguide 20 through which the optical signal passes, and an optical signal between the PD 6 and the optical waveguide 20 through which the optical signal passes. In the optical path portion, it is made of a transparent resin that allows optical signals to pass through. Examples thereof include cycloolefin polymer, PMMA, and polycarbonate.

  Next, the operation of the optical module according to the embodiment of the present invention will be described. First, when a first electrical signal is input to the drive element 3 via the electrical connector 12 connected to the first external device and the electrical wiring (not shown) provided on the substrate 10, the drive element 3 Controls the light emission of the light emitting element LD2 based on the input first electric signal.

  Next, the LD 2 emits the above-described optical signal having a predetermined wavelength, and the optical signal enters the core layer 23 of the optical waveguide 20. The optical signal propagates along the core layer 23 of the optical waveguide 20 and enters the PD 6 through the optical waveguide 20. Then, the optical signal incident on the PD 6 is converted into a second electric signal by the PD 6, and the second electric signal is amplified by the signal amplifying element 7. The amplified electrical signal is output to a second external device connected to the electrical connector 15 via an electrical wiring (not shown) provided on the substrate 13 and the electrical connector 15. . As described above, the optical module 1 in the present embodiment is configured such that the LD 2 and the PD 6 are optically coupled via the optical waveguide 20.

  Next, as an example of an electric device in which the optical module 1 according to the present embodiment is used, a foldable mobile phone will be described as an example. FIG. 4 is a side view showing a mobile phone in which the optical module according to the present embodiment is used, and shows a state in which the mobile phone is opened. FIG. 5 shows the optical module according to the present embodiment. It is a side view which shows a mobile phone, Comprising: It is a figure which shows the state which closed the mobile phone.

  As shown in FIGS. 4 and 5, the mobile phone 50 includes an operation unit 51 and a display unit 52, and the operation unit 51 includes a first housing 54 and an inside of the first housing 54. And a first circuit board 55 housed in the housing. The display unit 52 includes a second housing 56 and a second circuit board 57 housed in the second housing 56. In addition, the mobile phone 50 includes a hinge part 53 that is a movable part for connecting the operation part 51 and the display part 52 (that is, the first and second housings) so as to be displaceable (that is, rotatable). ing. The hinge portion 53 includes a hinge shaft 58 and a bearing portion 60 in which a hole portion 59 into which the hinge shaft 58 is inserted is formed.

  Then, with the first casing 54 of the operation unit 51 held, the second casing 56 of the display unit 52 is swung so that the display unit 52 is centered on the hinge shaft 58 of the hinge unit 53. The mobile phone 50 is rotated and displaced, and the mobile phone 50 is in an open state shown in FIG. 3 or a closed state shown in FIG. As described above, the first casing 54 and the second casing 56 can be displaced from each other, and the relative positions of the first casing 54 and the second casing 56 are changed.

  In addition, the optical module 1 shown in FIGS. 1 and 2 is accommodated in the mobile phone 50. More specifically, as shown in FIGS. 4 and 5, the transmission optical module 5 is accommodated in the first casing 54, and the reception optical module 9 is accommodated in the second casing 56. The optical waveguide 20 is provided inside the hinge portion 53. The electrical connector 12 provided in the transmission optical module 5 is connected to a first circuit board 55 that is a first external device provided in the first housing 54. The first electric signal is input to the driving element 3 from the first circuit board 55 via the first and second driving electric power is supplied to the LD 2 and the driving element 3. Similarly, the electrical connector 15 provided in the receiving optical module 9 is connected to a second circuit board 57 that is a second external device provided in the second casing 56. The amplified second electrical signal is output to the second circuit board 57 connected to the electrical connector 15 via the electrical connector 15. Drive power is supplied from the second circuit board 57 to the PD 6 and the signal amplifying element 7 via the electrical connector 15.

  Here, as described above, in the present embodiment, in the transmission optical module 5, the electrical connector 12 for supplying the driving power of the LD 2 as the light emitting element and the driving element 3 is provided on the back surface 10 b of the substrate 10. In addition, in the receiving optical module 9, an electrical connector 15 for supplying driving power for the light receiving element 6 and the signal amplifying element 7 is provided on the back surface 13 b of the substrate 13. Accordingly, the component mounting area of the substrates 10 and 13 can be reduced as compared with the above-described conventional optical module having a card edge type electrical connector. As a result, since the optical modules 5 and 9 can be made compact, it is possible to cope with the downsizing of the electric equipment (that is, the mobile phone 50) in which the optical modules 5 and 9 are used.

  Further, in the conventional flexible wiring board, as described above, since the film-shaped optical waveguide is provided integrally with the substrate on the lower surface of the substrate, the flexibility and the bending property of the optical waveguide are reduced. It was difficult to deform the optical waveguide into a desired shape. Therefore, for example, when the optical waveguide of the conventional flexible wiring board is provided inside the hinge portion 53, there is a problem that it is difficult to assemble the mobile phone. On the other hand, in the present embodiment, as described above, since the optical waveguide 20 provided in the hinge portion 53 is formed of a polymer material, the flexibility and bendability of the optical waveguide 20 are improved. it can. Accordingly, since the optical waveguide 20 can be easily deformed into a desired shape, it is possible to flexibly cope with the operation in the hinge portion 53 (that is, the folding operation or the folding operation). Therefore, the mobile phone 50 can be easily assembled.

According to the present embodiment described above, the following effects can be obtained.
(1) In the present embodiment, in the transmission optical module 5, the electrical connector 12 for supplying the driving power of the light emitting element LD 2 and the electronic component driving element 3 is connected to the substrate 10. It is set as the structure provided in the back surface 10b. In the receiving optical module 9, an electrical connector 15 is provided on the back surface 13 b of the substrate 13 to supply driving power for the light receiving element 6 that is an optical element and the signal amplifying element 7 that is an electronic component. Accordingly, the component mounting area of the substrate 10 in the optical module 5 (or the substrate 13 in the optical module 9) can be reduced compared to the above-described conventional flexible substrate having a card edge type electrical connector. 5 (or the optical module 9) can be made compact. As a result, it is possible to cope with the downsizing of the electric device (for example, the above-described mobile phone 50) in which the optical module 5 (or the optical module 9) is used.

  (2) In this embodiment, the optical waveguide 20 is formed of a polymer material. Therefore, the flexibility and bendability of the optical waveguide 20 can be improved, and the optical waveguide 20 can be easily deformed into a desired shape.

  (3) In the present embodiment, as the polymer material forming the optical waveguide 20, at least one selected from an epoxy resin, a silicon resin, and an acrylic resin polyimide resin is used. Therefore, it becomes possible to form the optical waveguide 20 excellent in flexibility and bendability by using an inexpensive and versatile material.

In addition, you may change the said embodiment as follows.
In the above embodiment, the substrates 10 and 13 are made of a material such as quartz glass or silicon single crystal. However, the substrates 10 and 13 may be made of a polymer material. Examples of the polymer material include polyimide resin, polyamide resin, polyester resin, and polyethylene naphthalate resin.

  In the above embodiment, the optical waveguide 20 is configured to have a substantially circular cross section. However, the optical waveguide 20 having a substantially polygonal cross section (for example, a substantially rectangular cross section or a substantially hexagonal cross section) is used. Also good.

  As examples of utilization of the present invention, the present invention includes, for example, an optical module used in an electric device such as a mobile phone, and an electronic device that houses the optical module in a housing.

It is sectional drawing for demonstrating the optical module which concerns on embodiment of this invention. It is AA sectional drawing of FIG. It is sectional drawing for demonstrating the optical waveguide in embodiment of this invention. It is a side view which shows the mobile telephone in which the optical module which concerns on this embodiment is used, Comprising: It is a figure which shows the state which opened the mobile telephone. It is a side view which shows the mobile phone in which the optical module which concerns on this embodiment is used, Comprising: It is a figure which shows the state which closed the mobile phone.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Optical module, 2 ... Laser diode (light emitting element), 3 ... Drive element, 5 ... Optical module for transmission, 6 ... Photodiode (light receiving element), 7 ... Signal amplification element, 9 ... Optical module for reception, DESCRIPTION OF SYMBOLS 10 ... Board | substrate (1st board | substrate), 10a ... The surface of a board | substrate, 10b ... The back surface of a board | substrate, 12 ... Electrical connector (1st electrical connector), 12a ... Connection part of an electrical connector, 13 ... Board | substrate (2nd board | substrate) ), 13a ... front surface of the substrate, 13b ... back surface of the substrate, 15 ... electrical connector (second electrical connector), 15a ... connection portion of the electrical connector, 20 ... optical waveguide, 23 ... core layer, 24 ... clad layer, 30 DESCRIPTION OF SYMBOLS ... Sealing body, 31 ... Sealing body, 50 ... Cellular phone, 51 ... Operation part, 52 ... Display part, 53 ... Hinge part, 54 ... 1st housing | casing, 55 ... 1st circuit board, 56 ... 1st 2 casings, 57... Second circuit board, 5 ... hinge axis, 60 ... bearing part

Claims (6)

A substrate, an optical element provided on the surface of the substrate, an electronic component provided on the surface of the substrate and electrically connected to the optical element, and attached to the substrate, optically coupled to the optical element. An optical module comprising a coupled optical waveguide, an electrical connector connected to an external device, and an electrical connector for supplying driving power for the optical element and the electronic component,
An optical module, wherein the electrical connector is provided on a back surface of the substrate.   The optical module according to claim 1, wherein the optical waveguide is made of a polymer material.   The optical module according to claim 2, wherein the polymer material is at least one selected from an epoxy resin, a silicon resin, an acrylic resin, and a polyimide resin.   The optical device is a light emitting device that emits an optical signal to the optical waveguide, and the electronic component is a drive device for driving the light emitting device. 4. The optical module according to any one of 3.   The optical element is a light receiving element that receives an optical signal through the optical waveguide and converts the optical signal into an electric signal, and the electronic component is a signal amplifying element for amplifying the electric signal. The optical module according to claim 1, wherein the optical module is an optical module. A first housing for housing a first circuit board;
A second housing for housing a second circuit board;
A movable part that connects the first and second housings in a displaceable manner;
A first substrate; a light emitting element provided on a surface of the first substrate; emitting a light signal; and a light emitting element provided on the surface of the first substrate and electrically connected to the light emitting element, A driving element for driving the element and a first element provided on the back surface of the first substrate, connected to the first circuit board, and for supplying driving power to the light emitting element and the driving element A transmission optical module housed in the first housing; and
A second substrate, a light receiving element that is provided on a surface of the second substrate and receives the optical signal, converts the optical signal into an electric signal, and is provided on a surface of the second substrate. A signal amplifying element that is electrically connected to the light receiving element and amplifies the electric signal; and provided on a back surface of the second substrate, connected to the second circuit board, and the light receiving element And a second electrical connector for supplying driving power for the signal amplifying element, and a receiving optical module housed in the second housing,
An electrical apparatus comprising: an optical waveguide provided inside the movable part, formed of a polymer material, and optically coupling the light emitting element and the light receiving element.

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