JP2014017451A - Optical transmission system and surface-emitting semiconductor laser - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical transmission system in which a fault part can be specified without using an optical element for branching an optical signal, and to provide a surface-emitting semiconductor laser.SOLUTION: An optical transmission system 1 includes, as a transmitter 2, a surface-emitting semiconductor laser 20 having a plurality of first light-emitting parts 210A outputting a first optical signal 201 via a convex lens 220, and second light-emitting parts 210B outputting a second optical signal 202 having a spread angle θlarger than a spread angle θof the first optical signal 201, a multicore optical fiber 3 having a plurality of cores 30 of the same number as that of the first light-emitting parts 210A and transmitting the plurality of first optical signals 201 and second optical signals 202 received from the transmitter 2, and a light-receiving element 40 having a plurality of light-receiving parts 410 for receiving the plurality of first optical signals 201 and second optical signals 202 transmitted by the multicore optical fiber 3.

Description

  The present invention relates to an optical transmission system and a surface emitting semiconductor laser.

  As the amount of information transmitted increases, optical transmission using optical fibers capable of high-speed and large-capacity transmission has become mainstream. Among them, in order to further improve the signal density, a multi-core optical fiber having a plurality of cores in one fiber has been developed, and is considered to become the mainstream of information transmission in the future.

  For the optical transmission, a light emitting element including a plurality of light emitting units is used. However, it is necessary to specify a fault location in the optical transmission system. As a technique for identifying a failure location, a light quantity monitoring device for a surface emitting semiconductor laser has been proposed (see, for example, Patent Document 1).

  This light quantity monitoring device is fixed to a surface emitting semiconductor laser and splits a laser beam emitted from the surface emitting semiconductor laser as a part of monitor light, and light for detecting monitor light branched by the beam splitter. And a detector.

JP-A-8-330661

  SUMMARY OF THE INVENTION An object of the present invention is to provide an optical transmission system and a surface emitting semiconductor laser that can identify a failure location without using an optical element that branches an optical signal.

  As one aspect of the present invention, the following optical transmission system and surface emitting semiconductor laser are provided.

[1] A plurality of first output units that output a first optical signal, and a second output unit that outputs a second optical signal having a divergence angle larger than the divergence angle of the first optical signal. A plurality of cores equal to the number of the transmission device and at least the first output unit of the transmission device; and the plurality of first optical signals and the second optical signals output from the transmission device. An optical transmission comprising: an optical transmission path that receives and transmits light; and a receiving device that includes a plurality of light receiving units that receive the plurality of first optical signals and the second optical signal transmitted by the optical transmission path. system.
[2] The transmission device includes a plurality of first light emitting units that output the first optical signal via a condensing member having a condensing property, and the concentrating member without a condensing member. A surface-emitting type semiconductor laser having a second light-emitting unit that outputs a second optical signal, and the first output unit is configured by the condensing member and the first light-emitting unit, The optical transmission system according to [1], wherein the second output unit is configured by a light emitting unit.
[3] The optical transmission system according to [2], wherein the plurality of condensing members are disposed on the plurality of first light emitting units of the surface emitting semiconductor laser.
[4] The optical transmission system according to [2], wherein the plurality of condensing members are arranged apart from the surface emitting semiconductor laser.
[5] The transmission device outputs a plurality of first light emitting units that output the first optical signal, and the second optical signal having a spread angle larger than the spread angle of the first optical signal. A surface-emitting type semiconductor laser having a second light emitting unit, wherein the first light emitting unit constitutes the first output unit, and the second light emitting unit constitutes the second output unit. 1]. The optical transmission system according to 1].
[6] The transmission apparatus has a first mode for outputting the first optical signal and a second mode for outputting the second optical signal, and switching between the first and second modes. The optical transmission system according to [1], further including a control unit configured to perform output control of the first and second output units.

[7] A plurality of first light emitting units that output a first light signal to form a plurality of first light spots on a predetermined surface, and a second light signal that is output to the predetermined surface. A surface-emitting type semiconductor laser comprising: a second light-emitting unit that forms a second light spot so as to include the plurality of first light spots on the formed surface.
[8] The surface-emitting type semiconductor laser according to [7], wherein a plurality of condensing members having light condensing properties are disposed on emission surfaces of the plurality of first light emitting units.

According to the first and seventh aspects of the invention, it is possible to identify a failure location with a configuration that does not use an optical element that branches an optical signal.
According to the second aspect of the present invention, the spread angle of the first and second optical signals can be adjusted by the presence or absence of the light collecting member.
According to the third and eighth aspects of the invention, the alignment adjustment of the surface emitting semiconductor laser is facilitated as compared with the configuration in which the condensing member is separated from the surface emitting semiconductor laser.
According to the invention which concerns on Claim 4, when a defect generate | occur | produces in a condensing member, it becomes respondable by replacing | exchanging the condensing member in which the defect generate | occur | produced.
According to the invention which concerns on Claim 5, a condensing member can be made unnecessary.
According to the invention which concerns on Claim 6, when there exists the light-receiving part which could not receive the 1st optical signal in a 1st mode, it can switch to a 2nd mode and can identify a failure location.

FIG. 1 is a sectional view showing a schematic configuration example of an optical transmission system according to the first embodiment of the present invention. FIG. 2 is a plan view of the surface emitting semiconductor laser. 3A is a cross-sectional view taken along the line AA in FIG. 2, and FIG. 3B is a cross-sectional view taken along the line BB in FIG. FIG. 4 is a cross-sectional view of a multi-core optical fiber. FIG. 5 is a plan view of the light receiving element. FIG. 6A is a schematic diagram showing the positional relationship between the surface emitting semiconductor laser and the multicore optical fiber, and FIG. 6B shows the distance L between the surface emitting semiconductor laser and the multicore optical fiber and the second relationship. It is a figure which shows the relationship with the spot size in the entrance plane of the multi-core optical fiber of the 2nd optical signal output from the light emission part. FIG. 7 is a diagram for explaining functions of the transmission control unit and the reception control unit. FIG. 8 is a diagram for explaining a method for adjusting the alignment between the surface emitting semiconductor laser and the multi-core optical fiber. FIG. 9 is a cross-sectional view showing a main part of an optical transmission system according to the second embodiment of the present invention. FIG. 10 is a cross-sectional view showing the main parts of an optical transmission system according to the third embodiment of the present invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, in each figure, about the component which has the substantially same function, the same code | symbol is attached | subjected and the duplicate description is abbreviate | omitted.

[First Embodiment]
FIG. 1 is a sectional view showing a schematic configuration example of an optical transmission system according to the first embodiment of the present invention. 2 is a plan view of the surface emitting semiconductor laser, FIG. 3A is a cross-sectional view taken along line AA in FIG. 2, and FIG. 3B is a cross-sectional view taken along line BB in FIG. FIG. 4 is a cross-sectional view of a multi-core optical fiber. FIG. 5 is a plan view of the light receiving element.

  As illustrated in FIG. 1, the optical transmission system 1 includes a transmission device 2 that transmits a plurality of optical signals, a multicore optical fiber 3 that transmits a plurality of optical signals transmitted from the transmission device 2, and a multicore optical fiber 3. And a receiving device 4 for receiving a plurality of optical signals transmitted by.

  The transmission device 2 includes a surface emitting semiconductor laser 20, a support member 21 that supports end portions of the surface emitting semiconductor laser 20 and the multicore optical fiber 3 on the light signal incident side, and the surface emitting semiconductor laser 20 as a switch unit. 22, a drive circuit 23 that is driven via 22, a transmission control unit 24 that controls the switch unit 22 and the drive circuit 23, and a memory 25 that stores transmission data.

  The receiving device 4 includes a light receiving element 40, a support member 41 that supports the light receiving element 40 and the end of the optical signal output side of the multi-core optical fiber 3, an amplification circuit 42 that amplifies the output signal of the light receiving element 40, and amplification A reception control unit 43 that controls the circuit 42 and a memory 44 that stores reception data are provided. The transmission control unit 24 and the reception control unit 43 are connected by an electric transmission path 45.

(Multi-core optical fiber)
As shown in FIGS. 1 and 4, the multi-core optical fiber 3 corresponds to a plurality of first light emitting portions 210 </ b> A (described later) of the surface emitting semiconductor laser 20 at equal intervals on a concentric circle with respect to the central axis 3 a. A plurality of (for example, six) cores 30 arranged, and a clad 31 formed around the core 30 and having a refractive index lower than the refractive index of the core 30 are configured. The multi-core optical fiber 3 includes a silica glass-based optical fiber in which the core 30 and the clad 31 are made of quartz glass, a polymer clad optical fiber in which the core 30 is made of quartz glass, and the clad 31 is made of plastic, the core 30 and the clad A plastic optical fiber 31 formed of plastic can be used. The multi-core optical fiber 3 is an example of an optical transmission path. The optical transmission path may be an optical waveguide. Further, a protective layer may be provided on the outer periphery of the clad 31. The multi-core optical fiber 3 may be a single mode optical fiber or a multi mode optical fiber.

(Support member)
The support member 21 of the transmission device 2 is provided with a plate-like base portion 21a, a plate-like first support portion 21b that is provided so as to be orthogonal to the base portion 21a, and supports the surface emitting semiconductor laser 20, and a base portion And a plate-like second support portion 21c that is provided so as to be orthogonal to 21a and supports the end portion of the multi-core optical fiber 3 on the light incident side. On the support member 21, a wiring pattern (not shown) connected to an electrode (described later) of the surface emitting semiconductor laser 20 is formed.

  The support member 41 of the receiving device 4 is provided so as to be orthogonal to the plate-like base portion 41a, the base portion 41a, and orthogonal to the plate-like first support portion 41b that supports the light receiving element 40 and the base portion 41a. And a plate-like second support portion 41c that supports the end portion of the multi-core optical fiber 3 on the light emission side. The support member 41 is formed with a wiring pattern (not shown) connected to an electrode (described later) of the light receiving element 40.

  The two support members 21 and 41 are provided on a common base portion, the first and second support portions 21b and 21c on the transmission device 2 side, and the first and second support portions 41b on the reception device 4 side, 41c may be provided.

(Surface emitting semiconductor laser)
The surface emitting semiconductor laser 20 is a surface light emitting element having a mounting surface opposite to the light output surface that outputs an optical signal. For example, as shown in FIGS. 1 and 2, a substrate made of n-type GaAs. 200, a first light emitting unit 210A having a plurality of (for example, six) mesa portions arranged on the substrate 200 at equal intervals on a concentric circle with respect to the center 20a of the substrate 200, and the center 20a of the substrate 200. The second light emitting unit 210B by the mesa unit, and six convex lenses 220 arranged on the optical signal output side of each first light emitting unit 210A. As the surface emitting semiconductor laser 20, a light emitting element that emits single mode or multimode laser light can be used.

  The lens 220 is an example of a light collecting member having light collecting properties. The condensing member may be a Fresnel lens, a refractive index distribution lens, a diffractive optical element, or the like. The first and second light emitting units 210A and 210B may be light emitting diodes.

The first light emitting unit 210A and the lens 220 constitute a first output unit. The second light emitting unit 210B constitutes a second output unit. As shown in FIG. 1, the first optical signal 201 output from the first output unit has a narrow divergence angle θ ₁ so that the entire light beam enters the opposing core 30 of the multicore optical fiber 3. The second optical signal 202 output from the second output unit has a spread angle θ ₂ wider than the spread angle θ 1 of the first optical signal 201 so as to enter all the cores 30 of the multi-core optical fiber 3. .

  As shown in FIG. 2, the surface-emitting type semiconductor laser 20 includes a p-side electrode 215 having an opening 215a on the light output surface side of the first light-emitting portion 210A, and the p-side electrode 215 is connected to a wiring pattern 216A. A conductive pattern is formed so as to reach the electrode pad 217. Similarly, in the surface emitting semiconductor laser 20, a p-side electrode 215 having an opening 215a is formed on the light output side of the second light emitting unit 210B, and an electrode pad is formed from the p-side electrode 215 via the wiring pattern 216B. A conductive pattern is formed to reach 217. The opening 215a serves as an exit from which the optical signal exits.

  The plurality of first light emitting units 210 </ b> A of the surface emitting semiconductor laser 20 configured in this way outputs the first optical signal 201 through the lens 220 and is a predetermined surface, that is, the multi-core optical fiber 3. A plurality of first light spots are formed on the incident surface 3b. The second light emitting unit 210B outputs a second optical signal 202 and forms a second light spot on the incident surface 3b of the multicore optical fiber 3 so as to include a plurality of first light spots.

As shown in FIG. 3A, the second light emitting unit 210B arranged at the center 20a of the substrate 200 has an n-type lower DBR made of an Al _x Ga _(1-x) As multilayer film on the substrate 200. A layer 211, an active layer 212 made of MQW, a current confinement layer 213 having an aperture 213a, a p-type upper DBR layer 214 made of an Al _x Ga _(1-x) As multilayer film, and a p-side electrode 215 having an opening 215a. They are formed in order. In the surface emitting semiconductor laser 20, an n-side electrode 230 is formed on the lower surface of the substrate 200. The electrode pad 217 and the n-side electrode 230 are connected to the switch unit 22 and the drive circuit 23 side through the wiring pattern of the support member 21.

  As shown in FIG. 3B, each first light emitting portion 210A arranged concentrically with respect to the center 20a of the substrate 200 is a convex lens having a condensing property at the opening 215a of the p-side electrode 215. 220 is formed. The lens 220 is formed, for example, by applying a liquid resin using a method such as an ink jet and curing the entire spherical shape by surface tension by heat treatment or UV irradiation. As the spherical resin, for example, an acrylic resin or an epoxy resin can be used.

(Light receiving element)
The light receiving element 40 is a surface type light receiving element having a mounting surface on the side opposite to the light receiving surface that receives an optical signal. For example, a photodiode or the like can be used. As shown in FIGS. 1 and 5, the light receiving element 40 is equidistantly spaced concentrically with respect to the substrate 400 and the center 40 a of the substrate 400 corresponding to the plurality of cores 30 of the multicore optical fiber 3 on the substrate 400. And a plurality of (for example, six) light receiving units 410 arranged in the base. In this embodiment, the light receiving unit 410 uses a GaAs PIN photodiode having excellent high-speed response. The PIN photodiode includes, for example, a P-layer, an I-layer and an N-layer that are PIN-bonded on a substrate 400 made of GaAs, a p-side electrode 411 connected to the P-layer, and an n-side formed on the N-layer. An electrode 414.

  As shown in FIG. 5, a p-side electrode 411 having an opening 411 a is formed in the light receiving unit 410, and a conductive pattern is formed from the p-side electrode 411 to the electrode pad 413 through the wiring pattern 412. Yes. In the light receiving portion 410, an n-side electrode 414 is formed so as to surround the p-side electrode 411, and a conductive pattern is formed from the n-side electrode 414 to the electrode pad 416 through the wiring pattern 415. . The opening 411a serves as an entrance through which an optical signal enters. The electrode pads 413 and 416 are connected to the amplifier circuit 42 via the wiring pattern of the support member 41.

  6A is a schematic diagram showing a positional relationship between the surface emitting semiconductor laser 20 and the multi-core optical fiber 3, and FIG. 6B is a distance between the surface emitting semiconductor laser 20 and the multi-core optical fiber 3. FIG. It is a figure which shows the relationship between L and the spot size in the entrance plane 3b of the multi-core optical fiber 3 of the 2nd optical signal 202 output from the 2nd light emission part 210B.

  For example, when the diameter of the multi-core optical fiber 3 is 125 μm, the diameter of the core 30 is 8 μm, and the distance from the center axis 3a to the center of the core 30 is 35 μm, the radius of the circle circumscribing each core 30 is 39 μm. Suppose that the spot size (radius r) of the second optical signal 202 on the incident surface 3b of the multi-core optical fiber 3 is set to 50 μm so that the circle is included. When the spread angle (one side) of the second optical signal 202 is 15 °, the distance L is set to 150 μm or more. When the spread angle (one side) is 9 °, the spot size ( The radius r) is 50 μm. For mounting the surface emitting semiconductor laser 20, it is common to use a bonding wire, and since a gap of 100 μm or more is usually provided, the value of the distance L is sufficient.

  FIG. 7 is a diagram for explaining the functions of the transmission control unit 24 and the reception control unit 43. The switch unit 22 of the transmission device 2 includes a first terminal 22a connected to the drive circuit 23, a second terminal 22b connected to each first light emitting unit 210A, and a second terminal connected to the second light emitting unit 210B. 3 terminal 22c and the movable piece 22d which connects the 1st terminal 22a to the 2nd terminal 22b or the 3rd terminal 22c are provided.

  The transmission control unit 24 and the reception control unit 43 have a first mode for outputting the first optical signal 201, for example, a communication mode, and a second mode for outputting the second optical signal 202, for example, an inspection mode.

  The transmission control unit 24 controls the output of the optical signal by switching between the communication mode and the inspection mode. That is, in the communication mode, the transmission control unit 24 controls the switch unit 22 to connect the movable piece 22d to the second terminal 22b, and controls the drive circuit 23 to transmit the first light from each first light emitting unit 210A. In the inspection mode, the switch 201 is controlled to connect the movable piece 22d to the third terminal 22c and the drive circuit 23 is controlled to control the second light signal 202 from the second light emitting unit 210B. Is output.

  In the communication mode, the reception control unit 43 transmits a signal requesting switching to the inspection mode to the transmission device 2 via the electrical transmission path 45 when the optical signal cannot be received from some of the light receiving units 410. It is configured as follows. In the inspection mode, the reception control unit 43 receives a detection signal corresponding to the amount of light received by each light receiving unit 410 from the amplifier circuit 42, and when the light amount is smaller than the threshold value, the corresponding core 30 or the multi-core optical fiber 3 It is determined that the corresponding light receiving unit 410 of the light receiving element 40 is abnormal, and when the light amount is equal to or greater than the threshold value, it is determined that the multi-core optical fiber 3 and the light receiving element 40 are normal, and the determination result is output to a display unit or the like. .

  FIG. 8 is a diagram for explaining a method for adjusting the alignment between the surface emitting semiconductor laser 20 and the multi-core optical fiber 3. In this case, the second light emitting unit 210B is turned on, the surface light receiving element 6 represented by a CCD (Charge Coupled Device) is used as the light receiving element, and the amount of light received through each core 30 is uniform. The alignment in the x direction and y direction of the surface emitting semiconductor laser 20 is adjusted so that The alignment of the multi-core optical fiber 3 in the x direction and the y direction may be adjusted.

(Operation of the first embodiment)
Next, an example of the operation of the first embodiment will be described. First, the transmission control unit 24 of the transmission device 2 performs control in the communication mode, and transmits the first optical signal 201 to the reception device 4. That is, the switch section 22 is controlled to connect the movable piece 22d to the second terminal 22b, and the drive circuit 23 is controlled based on the transmission data stored in the memory 25 to control each of the surface emitting semiconductor lasers 20. The first light signal 201 is output from one light emitting unit 210A.

  The first optical signal 201 is transmitted through the core 30 of the multi-core optical fiber 3 and is received by the light receiving unit 410 of the light receiving element 40. The light receiving unit 410 that has received the first optical signal 201 outputs an electrical signal corresponding to the light amount of the first optical signal 201 to the amplifier circuit 42. The amplifier circuit 42 amplifies the electrical signal output from the light receiving unit 410. The reception control unit 43 converts the electrical signal output from the amplifier circuit 42 into digital data, and stores the digital data in the memory 44 as reception data.

  In the communication mode, the reception control unit 43 transmits a signal requesting switching to the inspection mode to the transmission device 2 via the electrical transmission path 44 when the optical signal cannot be received from some of the light receiving units 410. .

  When receiving a signal for requesting switching to the inspection mode, the transmission control unit 24 of the transmission device 2 switches from the communication mode to the inspection mode.

  In the inspection mode, the transmission control unit 24 controls the switch unit 22 to connect the movable piece 22d to the third terminal 22c, and also controls the driving circuit 23 to control the second light signal 202 from the second light emitting unit 210B. Is output.

  The second optical signal 202 is transmitted through the core 30 of the multi-core optical fiber 3 and received by the light receiving unit 410 of the light receiving element 40. The light receiving unit 410 that has received the first optical signal 201 outputs an electrical signal corresponding to the light amount of the first optical signal 201 to the amplifier circuit 42. The amplifier circuit 42 amplifies the electrical signal output from the light receiving unit 410.

  The reception control unit 43 receives a detection signal corresponding to the amount of light received by each light receiving unit 410 from the amplifier circuit 42, and when the light amount is smaller than the threshold value, the corresponding core 30 or light receiving element 40 of the multi-core optical fiber 3 is received. When the corresponding light receiving unit 410 is determined to be abnormal and the light amount is equal to or greater than the threshold value, it is determined that the multi-core optical fiber 3 and the light receiving element 40 are normal, and the determination result is output to a display unit or the like.

(Effects of the first embodiment)
According to the first embodiment, the following effects are obtained.
(A) When there is a light receiving unit 410 that does not receive the first optical signal in the communication mode even though the optical element that branches the optical signal is not used, the second light is switched to the inspection mode. By examining whether or not a signal can be received, it is possible to identify whether the failure is on the surface emitting semiconductor laser side or the multi-core optical fiber side.
(B) The spread angle of the first and second optical signals can be adjusted by the presence or absence of the lens 220.
(C) Since the lens 220 is provided in the surface-emitting type semiconductor laser 20, alignment adjustment of the surface-emitting type semiconductor laser 20 becomes easier as compared with a configuration in which the lens 220 is separated from the surface-emitting type semiconductor laser 20.

[Second Embodiment]
FIG. 9 is a cross-sectional view showing a main part of an optical transmission system according to the second embodiment of the present invention. In the first embodiment, a surface emitting semiconductor laser provided with a lens is used. However, in the present embodiment, the lens is separated from the surface emitting semiconductor laser, and the others are the first embodiment. It is configured in the same way. The following description will focus on differences from the first embodiment.

  The transmission device 2 according to the present embodiment includes a surface emitting semiconductor laser 20 and a lens array 5, and the same support member 21, switch unit 22, drive circuit 23, and transmission control unit 24 as those in the first embodiment. And a memory 25.

  The lens array 5 includes a plurality of (for example, six) convex lenses 50 arranged concentrically and a lens holder 51 that holds each lens 50. The lens holder 51 includes an opening 51a that houses the lens 50, and a window 51b that allows the second optical signal 202 output from the second light emitting unit 210B to pass therethrough. The lens 50 is an example of a light collecting member having light collecting properties. The condensing member may be a Fresnel lens, a refractive index distribution lens, a diffractive optical element, or the like.

(Effect of the second embodiment)
According to the second embodiment, when a defect occurs in the lens 50, it can be dealt with by replacing the lens 50 or the lens array 5 in which the defect has occurred.

[Third Embodiment]
FIG. 10 is a cross-sectional view showing a main part of an optical transmission system according to the second embodiment of the present invention. In the first and second embodiments, the lens is used to control the spread angle of the optical signal. However, in this embodiment, the spread angle of the optical signal is controlled by the surface emitting semiconductor laser itself without using the lens. The others are configured in the same manner as in the first embodiment. The following description will focus on differences from the first embodiment.

  The surface emitting semiconductor laser 20 according to the present embodiment has a second angle greater than the spread angle of the first optical signal 201 output from the first light emitting unit 210A due to, for example, a change in the size of the aperture 213a of the current confinement layer 213. The spread angle of the second optical signal 202 output from the light emitting unit 210B is configured to be wide.

  The plurality of first light emitting units 210 </ b> A of the surface emitting semiconductor laser 20 configured as described above outputs the first optical signal 201 on the predetermined surface, that is, the incident surface 3 b of the multicore optical fiber 3. A plurality of first light spots are formed. The second light emitting unit 210B outputs a second optical signal 202 and forms a second light spot on the incident surface 3b of the multicore optical fiber 3 so as to include a plurality of first light spots.

(Effect of the third embodiment)
According to the present embodiment, a lens can be dispensed with, and the configuration can be simplified compared to a configuration using a lens. The first light emitting unit 210A may emit a single mode laser beam, and the second light emitting unit 210B may emit a multi mode laser beam.

[Modification]
The embodiments of the present invention are not limited to the above-described embodiments, and various modifications and implementations are possible without departing from the scope of the present invention. For example, in each of the above embodiments, the first light emitting unit of the surface emitting semiconductor laser, the core of the multi-core optical fiber, and the light receiving unit of the light receiving element are arranged concentrically, but may be arranged on a straight line. .

  In each of the above embodiments, the number of the first light emitting unit of the surface emitting semiconductor laser, the core of the multi-core optical fiber, and the number of the light receiving units of the light receiving element are each six. That's all.

  Moreover, a core may be arrange | positioned at the center axis line of a multi-core optical fiber, and a light-receiving part may be arrange | positioned in the center of a light receiving element. Thus, the second optical signal output from the second light emitting unit of the surface emitting semiconductor laser can be transmitted to the light receiving unit disposed at the center of the light receiving element.

  In the first and second embodiments, a lens is arranged corresponding to the first light emitting unit, and no lens is arranged for the second light emitting unit. Corresponding to the above, a lens having a light collecting property lower than that of the lens for the first light emitting unit may be arranged.

  In each of the above embodiments, the center of the surface emitting semiconductor laser is aligned with the central axis of the multicore optical fiber, but 45 ° mirrors are disposed on the incident surface side and the output surface side of the multicore optical fiber, respectively. The light output surface of the surface emitting semiconductor laser and the light receiving surface of the light receiving element may be opposed to the incident surfaces of the respective 45 ° mirrors. Further, instead of arranging the 45 ° mirror, the incident surface and the exit surface of the multi-core optical fiber may be inclined at 45 °, and the inclined surface may be used as the reflecting surface.

  Further, it is possible to omit some of the constituent elements of each of the above embodiments within the scope not changing the gist of the present invention.

DESCRIPTION OF SYMBOLS 1 ... Optical transmission system, 2 ... Transmission apparatus, 3 ... Multi-core optical fiber, 3a ... Center axis, 3b ... Incident surface, 4 ... Reception apparatus, 5 ... Lens array, 6 ... Surface light-receiving element, 20 ... Surface emitting semiconductor Laser, 20a ... center, 21 ... support member, 21a ... base portion, 21b ... first support portion, 21c ... second support portion, 22 ... switch portion, 22a ... first terminal, 22b ... second terminal, 22c 3rd terminal 22d Movable section 23 Drive circuit 24 Transmission control unit 25 Memory 30 Core 31 Clad 40 Light receiving element 40a Center 41 Support member 41a Base Part 41b ... first support part 41c ... second support part 42 ... amplifier circuit 43 ... reception control part 44 ... memory 45 ... electric transmission path 50 ... lens 51 ... lens holder 51a ... Opening, 51b ... Window, 20 ... Substrate, 201 ... first optical signal, 202 ... second optical signal, 210A ... first light emitting part, 210B ... second light emitting part, 211 ... lower DBR layer, 212 ... active layer, 213 ... current confinement Layer, 213a ... aperture, 214 ... upper DBR layer, 215 ... p-side electrode, 215a ... opening, 216A, 216B ... wiring pattern, 217 ... electrode pad, 220 ... lens, 230 ... n-side electrode, 400 ... substrate, 410 ... Light-receiving part, 411 ... p-side electrode, 411a ... opening, 412 ... wiring pattern, 413 ... electrode pad, 414 ... n-side electrode, 415 ... wiring pattern, 416 ... electrode pad

Claims (8)

A transmitter having a plurality of first output units that output a first optical signal, and a second output unit that outputs a second optical signal having a larger spread angle than the spread angle of the first optical signal; ,
At least a plurality of cores equal to the number of the first output units of the transmission device are received, and the plurality of first optical signals and the second optical signals output from the transmission device are received and transmitted. An optical transmission line
A receiving device having a plurality of light receiving sections for receiving the plurality of first optical signals and the second optical signals transmitted by the optical transmission path;
Optical transmission system equipped with. The transmission device includes a plurality of first light emitting units that output the first optical signal via a light collecting member having a light collecting property, and the second light emitting unit without using the light collecting member having a light collecting property. A surface emitting semiconductor laser having a second light emitting unit for outputting an optical signal,
The first output part is constituted by the light collecting member and the first light emitting part,
The optical transmission system according to claim 1, wherein the second output unit is configured by the second light emitting unit.   The optical transmission system according to claim 2, wherein the plurality of condensing members are disposed on the plurality of first light emitting units of the surface emitting semiconductor laser.   The optical transmission system according to claim 2, wherein the plurality of condensing members are arranged apart from the surface emitting semiconductor laser. The transmission device outputs a plurality of first light emitting units that output the first optical signal, and a second optical signal that outputs a second optical signal having a spread angle larger than a spread angle of the first optical signal. A surface emitting semiconductor laser having a light emitting portion;
The first output unit is configured by the first light emitting unit,
The optical transmission system according to claim 1, wherein the second output unit is configured by the second light emitting unit.   The transmission device has a first mode for outputting the first optical signal and a second mode for outputting the second optical signal, and performs switching between the first and second modes. The optical transmission system according to claim 1, further comprising a control unit that performs output control of the first and second output units. A plurality of first light emitting units for outputting a first optical signal to form a plurality of first light spots on a predetermined surface;
A surface-emitting type comprising: a second light-emitting unit that outputs a second light signal and forms a second light spot so as to include the plurality of first light spots on the predetermined surface. Semiconductor laser. The surface emitting semiconductor laser according to claim 7, wherein a plurality of condensing members having light condensing properties are disposed on the emission surfaces of the plurality of first light emitting units.

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