JP5400078B2 - Planar lightwave circuit connection device - Google Patents

Description

  The present invention relates to a planar lightwave circuit connection device.

  With the advancement of optical communication systems, the demand for highly functional optical modules (optical components) is increasing. A planar lightwave circuit can realize various lightwave circuits by forming an optical waveguide on a substrate, and is used as a component of an optical module. Realizing a hybrid optical module that integrates planar lightwave circuits with different functions, or integrates spatial optical components such as lenses and spatial phase modulators, and planar lightwave circuits to further enhance the functionality of optical modules Has been. Specific examples of the optical module include: (1) a V-AWG module in which an arrayed waveguide grating (AWG) and a variable optical attenuator (VOA) are formed on different planar lightwave circuit boards and then optically coupled to each other; (2) An RZ-DQPSK (Return to Zero Differential Phase Shift Keying) module in which a planar lightwave circuit composed of different materials such as quartz glass and lithium niobate (LN) is optically coupled.

Japanese Patent Laid-Open No. 10-227936 JP 2001-264576 A

  However, in order to produce a hybrid optical module with a small size, it is necessary to review from the production process. For example, in the technique of Patent Document 1 (see FIG. 1), in order to easily connect different types of planar lightwave circuits, at least two connection optical waveguides 15 are provided in addition to the waveguide 16 having a folded structure. However, in order to align and connect the first planar lightwave circuit 11 and the second planar lightwave circuit 12, it is necessary to bond and fix the optical fiber component 17 to the first planar lightwave circuit 11 in advance. Here, the optical fiber component 17 is manufactured by arranging the optical fiber 14 in one optical fiber fixing block 13. Further, in the technique of Patent Document 2 (see FIG. 2), an AWG capable of manufacturing an AWG device at low cost by performing alignment between the optical fiber component 121 and the optical device 111 with high accuracy and high speed. Although a manufacturing apparatus is disclosed, alignment using light guided through an optical fiber is also performed here. Briefly explain the alignment method. The optical device 111 formed from the arrayed waveguide 116, the slab waveguides 114 and 115, the input waveguide 112, and the optical waveguide 113 is held by the optical device fixing means 141, and the optical fiber tape 122 is aligned. The optical fiber component 121 is held by the optical device fixing means 142. The light receiver 134 can be moved by the light receiver moving means 143. The incident light 150 is incident on the optical fiber tape 122, and the alignment with the optical waveguide 112 is performed by detecting the monitor light 151 emitted separately from the signal light 152 by the light receiver 134 when the optical axes of the both are substantially coincident with each other. This is done by inputting the detection result to the control device 144.

  Such conventional techniques have the following problems. FIG. 3 is a diagram for explaining the problems of the prior art. In FIG. 3, first to third planar lightwave circuits 301, 302, and 303 are connected to each other, and first and second optical fibers 321 and 322 are connected to both ends by first and second fiber alignment members 311 and 312. 8 shows a situation in which the optical components fixed respectively are housed in an airtight sealing case 330 to produce the hybrid optical module 300. When the fiber outlet 331 is integrated with the case as in the case of the hermetic sealing case 330 shown in the figure, the first fiber 321 is allowed between the case and the optical component to which a plurality of planar lightwave circuits are connected. If there is no room for the bending diameter or more, the first fiber 321 is damaged and there is a risk of disconnection, so that the optical component cannot be accommodated. Since the bending radius r allowed for the fiber is generally considered to be a radius of 10 mm or more, the inner size of the case needs to be 20 mm or more longer than the light wave circuit in which a plurality of planar light wave circuits are connected. It was a restriction.

  The present invention has been made in view of such problems, and an object of the present invention is to provide a planar lightwave circuit connection device capable of downsizing an optical component to which a plurality of planar lightwave circuits are connected. It is in.

In order to achieve such an object, a first aspect of the present invention is a planar lightwave circuit connecting device for connecting a first planar lightwave circuit and a second planar lightwave circuit, wherein for holding a planar lightwave circuit, and at least one of the first holding jig having a light incident means, the second holding jig for holding said second planar lightwave circuit, with the least 1 Receives light for alignment that is incident on the alignment waveguide of the first planar lightwave circuit from one light incident means and is emitted from the alignment waveguide of the second planar lightwave circuit. A moving stage capable of aligning the alignment waveguide included in the first planar lightwave circuit and the alignment waveguide included in the second planar lightwave circuit. Features.

  Further, according to a second aspect of the present invention, in the first aspect, the second holding jig and the light receiving means are disposed on the moving stage, and the light receiving diameter of the light receiving means is: It is characterized by being larger than the beam diameter of the light for alignment emitted from the alignment optical waveguide of the second planar lightwave circuit.

  According to a third aspect of the present invention, in the first or second aspect, the first holding jig is a positioning member that serves as a position reference for the first planar lightwave circuit, and the first plane. A holding member for holding the light wave circuit, and the light incident means includes a light incident fiber or a light incident laser, and a holding member for fixing the light incident fiber or the light incident laser. The member is movable in the thickness direction of the first planar lightwave circuit.

  According to the present invention, in the planar lightwave circuit connection device for connecting the first planar lightwave circuit and the second planar lightwave circuit, the first holding jig for holding the first planar lightwave circuit is provided. By providing a moving stage capable of aligning the aligning waveguide of the first planar lightwave circuit and the aligning waveguide of the second planar lightwave circuit by providing at least one light incident means, When connecting a plurality of planar lightwave circuits, it is not necessary to connect an optical fiber directly to the planar lightwave circuit. As a result, for example, when housed in a hermetic sealing case, an optical fiber is not connected to an optical component to which a plurality of planar lightwave circuits are connected, and the optical module (optical component) can be downsized. it can.

It is a figure which shows the prior art of patent document 1. FIG. It is a figure which shows the prior art of patent document 2. FIG. It is a figure for demonstrating the problem of a prior art. It is a figure which shows the planar lightwave circuit connection apparatus which concerns on embodiment of this invention. (A) is a figure which shows the example which connected the 1st-3rd planar lightwave circuit by the planar lightwave circuit connection apparatus 400 by this invention, and accommodated in the case for airtight sealing, (b), It is a figure which shows the example which connected the optical fiber to the optical component accommodated in the case for airtight sealing. It is a figure which shows the modification of the planar lightwave circuit connection apparatus of FIG. (A) is a figure which shows the detail of a part of 1st holding jig, (b) is sectional drawing along the bb line. FIG. 4 is a diagram showing details of a first planar lightwave circuit 450.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 4 shows a planar lightwave circuit connection device according to an embodiment of the present invention. The planar lightwave circuit connection device 400 connects the first planar lightwave circuit 450 and the second planar lightwave circuit 460. The first planar lightwave circuit 450 is held by the first holding jig 410, and the second planar lightwave circuit 460 is held by the second holding jig 420. The first holding jig 410 is disposed on a moving stage 430 (for example, a six-axis moving stage), and the optical waveguide formed in the first planar lightwave circuit 450 and the second planar lightwave circuit 460. It is possible to align with the optical waveguide formed on the substrate.

  In the planar lightwave circuit connection device 400 according to the present invention, the first and second light incidents provided on the first holding jig 410 are not connected and fixed to the first planar lightwave circuit 450. By means 411, 412, light necessary for alignment is incident on the first and second alignment optical waveguides 451, 452 formed in the first planar lightwave circuit 450. Then, by receiving the light emitted from the second planar lightwave circuit 460 by the light receiving means 440, the first planar lightwave circuit 450 and the second planar lightwave circuit 460 can be aligned and connected. It becomes. The first and second light incident means 411, 412 and the light receiving means 440 are arranged so as not to correspond to each other in the first and second light incident means 411, 412. There is an effect of suppressing leakage light that has not been coupled to the second aligning optical waveguides 451 and 452 from entering the light receiving means 440 as noise.

  FIG. 4 shows the connection state of two planar lightwave circuits. By repeating the same procedure, a plurality of planar lightwave circuits are connected to produce an optical component without connecting optical fibers. Is possible.

  Since no optical fiber is connected to the optical component to which a plurality of planar lightwave circuits thus manufactured are connected, the optical component can be easily stored in an airtight sealing case in which the fiber outlet is integrated with the case. it can. FIG. 5A shows an example in which the first to third planar lightwave circuits 401, 402, and 403 are connected by the planar lightwave circuit connection device 400 according to the present invention and stored in the hermetic sealing case 430. Then, after the optical components connected with the first to third planar lightwave circuits are stored in the hermetic sealing case, the fiber alignment members 511 and 512 having the optical fibers 421 and 422 disposed therein are connected to thereby realize a small hybrid. An optical module can be manufactured. In FIG. 5A, after optical fibers 421 and 422 have been passed through the fiber outlet 431 in advance, the optical components to which the first to third planar lightwave circuits are connected are accommodated in an airtight sealing case 430. If the fiber alignment member is large enough to pass through the extraction port, it is possible to first store the optical component connected with the first to third planar lightwave circuits in the hermetic sealing case. There is an advantage that the optical fiber does not get in the way when being stored and fixed in the stop case. FIG. 5B shows an example in which an optical fiber is connected to an optical component housed in a hermetic sealing case. The connection between the optical component and the optical fiber is possible by aligning light so that light enters one optical fiber 421 and the light emitted from the other optical fiber 422 is maximized as in the conventional alignment process. It becomes.

  In the above description, the first and second planar lightwave circuits 450 and 460 each have two aligning optical waveguides, and correspondingly, the first holding jig 410 is also provided with two light incident means. However, it should be noted that the first holding jig 410 has no intention of limiting the number of light incident means to two. That is, even if there is only one light incident means, the first holding jig and the second holding jig are adjusted so that the first planar lightwave circuit and the second planar lightwave circuit do not shift in the θz direction. If so, it is possible to align the first planar lightwave circuit and the second planar lightwave circuit.

  FIG. 6 is a modification of the planar lightwave circuit connection device of FIG. Rather than arranging the first planar lightwave circuit 450 on the moving stage 430, the second holding jig 420 and the light receiving means 440 are arranged. Here, the light receiving diameter of the light receiving means 440 is made larger than the beam diameter of the emitted light from the first and second aligning optical waveguides 461 and 462 formed in the second planar lightwave circuit 460.

  The optical coupling strength between the first and second light incident means 411 and 412 and the first planar lightwave circuit 450 may slightly fluctuate due to vibration when the moving stage 430 moves. The light receiving diameter of the light receiving means 440 is made sufficiently larger than the beam diameter of the emitted light from the first and second aligning optical waveguides 461 and 462 of the second planar lightwave circuit 460, and the second holding jig 420. If the light receiving means 440 is fixed to the six-axis moving stage 430, the optical coupling strength between the first and second aligning optical waveguides 461 and 462 and the light receiving means 440 due to the movement of the six-axis moving stage 430. Fluctuations can be made sufficiently small.

  FIG. 7 shows details of the first holding jig. The first holding jig 410 includes a positioning member 413 that serves as a position reference for the first planar lightwave circuit 450 and a pressing member 414 that sandwiches the first planar lightwave circuit 450. FIG. 7A shows only the first holding jig 410 near one side surface of the first planar lightwave circuit 450, but the same structure is also provided near the other side surface. The first light incident means 411 includes a light incident fiber 411A and a holding member 411B that fixes the light incident fiber 411A. The light incident fiber holding member 411B is movable in the thickness direction of the first planar lightwave circuit 450 (see FIG. 7B).

  The optical coupling strength between the first aligning waveguide 451 and the light incident fiber 411A depends on the amount of optical axis misalignment between them. In order to reduce the optical axis deviation of each axis, the x direction is the distance between the surface where the pressing member 414 contacts the first planar lightwave circuit 450 and the end surface of the light incident fiber 411A, and the y direction is for light incidence. Adjustment is possible by making the fiber holding member 411B movable. The z direction is such that the optical coupling strength between the first alignment waveguide 451 and the light incident fiber 411A is maximized when the first planar lightwave circuit 450 is abutted against the positioning member 413. The optical axis deviation can be suppressed by processing the length of the planar lightwave circuit 450 in the z direction in advance with high accuracy.

  Instead of the light incident fiber 411A, a light incident laser may be used. It is also possible to improve the optical coupling strength by arranging a lens between the light incident fiber 411A and the end face 450A.

  FIG. 8 shows details of the first planar lightwave circuit 450. The waveguide width of the first aligning waveguide 451 gradually increases toward the end face 450A of the first planar lightwave circuit 450 facing the first light incident means 411. A similar structure can be considered for the second alignment waveguide 452.

  By increasing the waveguide width of the aligning waveguide, it is possible to increase the tolerance of the optical axis deviation in the z direction.

400 Planar lightwave circuit connection device 410 First holding jig 411 First light incident means 411A Light incident fiber 411B Holding member 412 Second light incident means 413 Positioning member 414 Holding member 420 Second holding jig 430 6 Axis moving stage 440 Light receiving means 450 First planar lightwave circuit 450A End surface of first planar lightwave circuit 450 451 First alignment waveguide 452 Second alignment waveguide 460 Second planar lightwave circuit 461 First aligning waveguide 462 Second aligning waveguide

Claims (3)

A planar lightwave circuit connecting device for connecting a first planar lightwave circuit and a second planar lightwave circuit,
A first holding jig having at least one light incident means for holding the first planar lightwave circuit;
A second holding jig for holding the second planar lightwave circuit;
Wherein at least incident on one of the first alignment waveguide having a planar lightwave circuit from the light projecting means, said second planar lightwave circuit is emitted from the alignment waveguide having, for aligning Light receiving means for receiving the light of
The planar lightwave circuit connection further comprising a moving stage capable of aligning the aligning waveguide of the first planar lightwave circuit and the aligning waveguide of the second planar lightwave circuit. apparatus. The second holding jig and the light receiving means are disposed on the moving stage,
The light receiving diameter of the light receiving means is larger than a beam diameter of the light for alignment emitted from the alignment optical waveguide included in the second planar lightwave circuit. Planar lightwave circuit connection device. The first holding jig is
A positioning member serving as a position reference for the first planar lightwave circuit;
A pressing member for sandwiching the first planar lightwave circuit,
The light incident means is
A light incident fiber or light incident laser, and a holding member for fixing the light incident fiber or the light incident laser,
The planar lightwave circuit connecting device according to claim 1 or 2, wherein the holding member is movable in a thickness direction of the first planar lightwave circuit.

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