JP2007264441A - Optical coupling method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical coupling method for facilitating easy and highly accurate optical coupling between optical devices or between components of the optical devices. <P>SOLUTION: Two or more electro-conductive patterns 211a, 211b are formed along the x-axis on elevation parts near the edges of a recess of a first component 210 composing the optical device. Also, electro-conductive patterns 221a, 221b are formed along the x-axis on the bottom edge parts of a second component 220 composing the optical device. An angle θz of the second component is adjusted so that the electro-conductive pattern 211a is in contact with the electro-conductive pattern 221a in the optimum condition for making current flow across a terminal 212a. Further, the second component 220 is shifted so that the electro-conductive pattern 211b is in contact with the electro-conductive pattern 221b, to adjust the angle θx. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an optical coupling method in which optical devices or components constituting the optical device are aligned and optically coupled, and more particularly, to an optical coupling method in which alignment in the tilt direction can be performed easily and with high accuracy. .

  Optical communication is suitable for high-speed and large-capacity signal transmission, and has already been put into practical use in long-distance backbone communication systems. In such a communication system, a signal switching device that switches a signal transmission path is an indispensable device. In a conventional communication system, a method of once converting an optical signal into an electrical signal, switching a signal transmission path with a semiconductor switch, and then converting it again into an optical signal has been widely used. However, in recent years, since the speed and capacity of optical communication have been further increased, it has become impossible to cope with semiconductor switches. Therefore, development of an optical switch capable of switching a transmission path while maintaining an optical signal is in progress.

  The inventors of the present application have proposed an optical switch that switches the transmission path of an optical signal using the electro-optic effect in Patent Document 1. FIG. 1A is a plan view showing the optical switch, and FIG. 1B is a cross-sectional view taken along the line I-I in FIG.

  The optical switch includes an incident side optical waveguide unit 101, a collimating unit 102, an incident side optical deflection element unit 103, a common waveguide 104, an output side optical deflection element unit 105, a condensing unit 106, and an output side optical waveguide unit 107. Has been. The incident-side optical waveguide unit 101, the collimating unit 102, the common waveguide 104, the condensing unit 106, and the output-side optical waveguide unit 107 are formed by stacking optical films on the substrate 100. Further, the incident side light deflection element unit 103 and the emission side light deflection element unit 105 are formed on a substrate 100 after being formed using a material exhibiting an electro-optic effect.

  The incident-side optical waveguide portion 101 covers n optical waveguides (core layers) 101a (in the example shown in FIG. 1, n = 4) and these optical waveguides 101a and guides an optical signal by a difference in refractive index. The clad layer 101b is confined in the waveguide 101a. Similarly, the output-side optical waveguide unit 107 includes a plurality of optical waveguides (core layers) 107a and a clad layer that covers these optical waveguides 107a and confines an optical signal in the optical waveguide 107a by a difference in refractive index. 107b.

  The collimating unit 102 includes n sets of collimating lenses 102a. These collimating lenses 102a are formed by patterning a core layer and a cladding layer sandwiching the core layer from above and below in a predetermined shape. The light emitted from the optical waveguide 101a spreads radially, but becomes almost parallel light by the collimating lens 102a.

  The incident-side light deflection element unit 103 is provided with n sets of light deflection elements 103a. Each optical deflection element 103a has at least one pair of wedge-shaped electrodes sandwiching the optical waveguide from above and below, and changes the propagation direction of the optical signal using the electro-optic effect. In this example, n pairs of wedge-shaped electrodes are alternately arranged on the optical deflection element 103a along each transmission path.

  The common waveguide 104 is configured by a slab waveguide including a thin film core layer and a clad layer sandwiching the core layer from above and below. A plurality of optical signals output from the incident-side optical deflection element unit 103 pass through the common waveguide 104 at the same time, but these optical signals travel straight through the common waveguide 104 in a predetermined direction. The light is transmitted to the output side light deflection element unit 105 without interfering with the signal.

  The exit side optical deflection element section 105 is provided with an optical deflection element 105a in which m pairs (m = 4 in the example shown in FIG. 1) of wedge-shaped electrodes are formed. These light deflecting elements 105a deflect light that has reached the light deflecting element 105a through the common waveguide 104 in a direction parallel to the optical waveguide 107a. The emission side light deflection element unit 105 has the same structure as the incident side light deflection element unit 103.

  The condensing unit 106 includes m sets of condensing lenses 106a. Similar to the collimating lens 103a, these condenser lenses 106a are also formed by patterning a core layer and a cladding layer sandwiching the core layer from above and below in a predetermined shape. These condensing lenses 106 a function to condense light that has passed through the light deflection element 105 a and guide it to the optical waveguide 107.

  In the thus configured optical switch, when no voltage is applied to the optical deflection elements 103a and 105a, the optical signal incident on the i-th optical waveguide 101a (i is an arbitrary integer from 1 to n) is After being converted into parallel light by the collimating lens 102a, the light travels straight through the light deflection element 103a, the common waveguide 104, and the light deflection element 105a, is condensed by the condenser lens 106a, and is transmitted to the i-th optical waveguide 107a. .

  On the other hand, when a predetermined voltage is applied to the optical deflection elements 103a and 105a, the traveling direction of the optical signal incident on the i-th optical waveguide 101a is bent at an angle corresponding to the voltage by the optical deflection element 103a. Then, the light travels straight through the common waveguide 104 and is transmitted to the j-th optical deflection element 105a (j is an arbitrary integer from 1 to m, where i ≠ j). Thereafter, the light is refracted by the light deflecting element 105a and transmitted to the jth optical waveguide 107a through the jth condenser lens 106a.

Other conventional techniques related to the present invention are described in Patent Document 2.
JP 2002-318398 A Japanese Patent Laid-Open No. 2000-241737

  In general, an optical communication system is configured by optically coupling optical fibers, optical switches, and other optical devices. In addition, as shown in FIGS. 1A and 1B, there is an optical device formed by optically coupling a plurality of components. Therefore, in order to construct an optical communication system, it is important to align optical devices or components with high accuracy. For example, in the optical switch shown in FIGS. 1A and 1B, the optical deflection element portions 103 and 105 are positioned on the substrate 100 while being aligned with the optical waveguides 101a and 107a, the collimating lens 102a, and the condenser lens 106a. It is necessary to install.

  When an optical device is formed by combining a plurality of component parts, alignment marks (alignment marks) are provided in advance on each component part, and each component part is aligned using these alignment marks. Conceivable. However, in this method, the horizontal direction shown in FIG. 2 (X-axis direction and Z-axis direction: in the present application, the Z-axis is the light propagation direction), and the rotation direction around the Y-axis (θy direction). Although alignment is possible, it is difficult to perform alignment in the tilt direction, that is, the rotation direction about the X axis (θx direction) and the rotation direction about the Z axis (θz direction).

  In the above-mentioned Patent Document 2, alignment channel waveguides are formed in the respective optical device component parts, and the respective component parts are arranged so that the coupling loss is minimized by passing light through the alignment channel waveguides. Alignment is described. However, in the method described in Patent Document 2, it is necessary to simultaneously adjust the axial direction (X-axis direction, Y-axis direction, and Z-axis direction) and the rotation direction (θx direction, θy direction, and θz direction), There is a drawback that the operation becomes complicated and the time required for alignment becomes long.

  In addition, it is difficult to employ this method in an optical device using a slab waveguide as shown in FIGS. That is, in the technique described in Patent Document 2, it is necessary to form alignment channel waveguides in the respective components constituting the optical device. However, in order to form the alignment channel waveguide in the slab waveguide, it is necessary to add many steps. In addition, in an optical device using an electro-optic material, it is extremely difficult to form a channel waveguide.

  There are also the following problems. That is, since the slab waveguide does not confine light in the lateral direction, alignment in the lateral direction (X-axis direction shown in FIG. 2) is usually unnecessary. However, in the technique described in Patent Document 2, it is necessary to form a channel waveguide in a component having a slab waveguide and to align the channel waveguide with the channel waveguide of another component with high accuracy. As a result, the advantage of the slab waveguide that it is easy to align is lost.

  In view of the above, an object of the present invention is to provide an optical coupling method capable of optically coupling optical devices or optical device components easily and with high accuracy.

  According to one aspect of the present invention, a plurality of first conductive patterns spaced apart from each other are formed in the vicinity of the edge of the upper surface of the first optical member, and the first optical pattern is formed in the vicinity of the edge of the lower surface of the second optical member. A second conductive pattern having a complementary relationship to the conductive pattern is formed, and a portion in the vicinity of the edge on the lower surface of the second optical member is projected to a portion in the vicinity of the edge on the upper surface of the first optical member. The angle of the second optical member is adjusted so that the plurality of first conductive patterns are electrically connected by the second conductive pattern, and the angle of the second optical member is adjusted. An optical coupling method is provided in which the second optical member is disposed at a predetermined position in a state and the first optical member and the second optical member are fixed.

  When the first optical member (the optical device or a component of the optical device) and the second optical member (the optical device or a component of the optical device) are optically coupled, the second optical member with respect to the first optical member It is necessary to adjust the angle (tilt angle). In this case, for example, it is conceivable to determine the angle of the second optical member by abutting the entire lower surface of the second optical member against the flat surface of the first optical member. However, in this method, if the first and second optical components are warped or deformed, or if there are protrusions due to foreign matter, the angle of the second optical member is shifted, and good optical coupling is achieved. Can't get.

  On the other hand, in the present invention, the inclination of the second optical member with respect to the first optical member by abutting the surface near the edge of the second optical member against the surface near the edge of the first optical member. Therefore, there is little possibility of being affected by warpage, deformation, protrusions due to foreign matters, etc., and high-accuracy alignment (optical coupling) becomes possible.

  In the present invention, the first conductive pattern formed near the edge of the upper surface of the first optical member is brought into contact with the second conductive pattern formed near the edge of the lower surface of the second optical member. Let Thereby, it can be electrically detected whether the surface near the edge of the upper surface of the first optical member and the surface near the edge of the lower surface of the second optical member are in good contact. As a result, the angle of the second optical member with respect to the first optical member can be easily adjusted with high accuracy.

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

(First embodiment)
FIG. 3 is a perspective view showing an optical coupling method according to the first embodiment of the present invention. Here, as shown in FIG. 3, a case where alignment (optical coupling) of the two component parts 210 and 220 constituting the optical device is performed in the tilt direction (θx direction and θz direction) will be described. The first component 210 is provided with a recess. When the second component 220 is properly disposed in the recess, the first component 210 has a waveguide (not shown) and a second component. A waveguide (not shown) of the component 220 is optically coupled.

  As shown in FIG. 3, two sets of conductive patterns 211 a and 211 b are formed in advance along the width direction (X direction) on the high rim portion near the recess of the first component 210. As shown in FIG. 3, one set of conductive patterns 211a are arranged apart from each other along the right edge (edge) of the recess, and the other set of conductive patterns 211b is the left edge of the recess. (Edges) are spaced apart from each other. A terminal 212a is connected to the conductive pattern 211a disposed on the outermost side in the width direction (X-axis direction) of the conductive pattern 211a. Similarly, the terminal 212b is connected to the conductive pattern 211b arranged on the outermost side in the width direction (X-axis direction) among the conductive patterns 211b.

  In addition, a plurality of conductive patterns 221a and 221b are also formed along the width direction (X-axis direction) at the edges (both ends in the Z-axis direction) on the back surface side of the second component 220. As shown in FIG. 3, the conductive pattern 221a is disposed on the side facing the conductive pattern 211a, and the conductive pattern 221b is disposed on the side facing the conductive pattern 211b.

  The conductive pattern 211a of the first component 210 and the conductive pattern 221a of the second component 220 have a complementary relationship. That is, when these conductive patterns 211a and 221a overlap with each other in an optimum state, they are connected in the width direction (X-axis direction) to form one wiring, and electricity passes between the two terminals 212a. Similarly, the conductive pattern 211b of the first component 210 and the conductive pattern 221b of the second component 220 have a complementary relationship. When these conductive patterns 211b and 221b overlap in an optimal state, they are connected in the width direction (X-axis direction) to form one wiring, and electricity is passed between the two terminals 212b.

  4 to 7 are diagrams illustrating a method of adjusting the tilt angles θx and θz. First, as shown in FIG. 4, the first component 210 is placed on the fixed stage 230, and a continuity meter 233 is connected between the two terminals 212a. Further, the second component 220 is held under the electric precision movement stage 232 controlled by the control unit 231. The moving stage 232 can move the second component 220 in the X-axis direction, the Y-axis direction, and the Z-axis direction in accordance with a signal from the control unit 231, and the θx direction, θy direction, and θz It can be rotated by a certain angle in the direction.

  The moving stage 232 includes a position detection function (encoder or pulse counter of a pulse motor driving circuit: not shown) that can detect positions (coordinates) in the X-axis direction, the Y-axis direction, and the Z-axis direction, and θx , Θy, θz direction angle detection function (encoder or pulse motor drive circuit pulse counter or the like: not shown) is provided. Signals output from these position detection function and angle detection function are input to the control unit 231.

  After holding the second component 220 on the above-described precision movement stage 232, the precision movement stage 232 is controlled via the control unit 231, and the end surface of the second component 220 in the length direction (Z-axis direction) is controlled. The edge and the edge of the concave portion of the first component 210 face each other, and the angle in the θy direction is adjusted so that they are parallel to each other. Thereafter, as shown in FIG. 5, the second stage is configured such that the moving stage 232 is controlled so that the conductive pattern 221 a of the second component 220 is positioned above the conductive pattern 211 a of the first component 210. The component 220 is moved in the horizontal direction (X-axis direction and Z-axis direction).

  Next, as shown in FIG. 6, the conductive pattern 211 a of the first component 210 and the conductive pattern of the second component 220 are adjusted by adjusting the position in the height direction (Y-axis direction) and the angle in the θz direction. 221a is overlaid. 6 shows a side view when viewed from the direction indicated by the arrow A in FIG.

  When the conductive pattern 211a and the conductive pattern 221a overlap with each other without a gap, the value of the continuity meter 233 changes. Thereby, it turns out that the conductive pattern 211a and the conductive pattern 221a contacted. When the conductive pattern 211a and the conductive pattern 221a overlap with each other without a gap, it means that the tilt angle θz of the first component 210 and the tilt angle θz of the second component 220 coincide. The position (coordinates) in the Y-axis direction at this time is stored in the control unit 231. Further, the tilt angle θz of the precision moving stage 232 is fixed.

  If the value of the continuity meter 233 does not change even if the first component 210 and the second component 220 come into contact with each other, the angle θz is not appropriate. This component 220 is brought into contact with the first component 210.

  After adjusting the angle θz in this way, the continuity meter 233 is then connected between the two terminals 212b. Then, as shown in FIG. 7, the second component 220 is moved by the precision movement stage 232 so that the conductive pattern 221 b of the second component 220 is positioned above the conductive pattern 211 b of the first component 210. Move. Thereafter, in the same manner as described above, the position of the moving stage 232 in the Y-axis direction (height direction) is set so that the conductive pattern 211b of the first component 210 and the conductive pattern 221b of the second component 220 overlap. adjust. When the conductive pattern 211b and the conductive pattern 221b overlap, a current flows between the two terminals 212b, and the value of the continuity meter 233 changes. The position (coordinates) in the Y-axis direction at this time is stored in the control unit 231.

  Thus, when the coordinates in the Y-axis direction when the conductive pattern 211a and the conductive pattern 221a are brought into contact with each other, and the coordinates in the Y-axis direction when the conductive pattern 221b and the conductive pattern 221b are brought into contact with each other, From the difference, it is possible to calculate how much the second component 220 is rotated around the X axis, that is, the tilt angle θx of the second component 220 with respect to the first component 210. Based on the calculation result, the tilt angle θx of the second component 220 is adjusted.

  After adjusting the tilt angles θx and θz of the second component 220 as described above, the second component 220 is moved into the concave portion of the first component 210, and the X-axis direction and the Y-axis direction are moved. The Z-axis direction and the θy direction are adjusted. In the X-axis direction, the Z-axis direction, and the θy direction, for example, first alignment marks are provided in advance in the first component 210 and the second component 220, respectively, and the second alignment is performed so that these alignment marks coincide. This is done by moving the component 220. The adjustment in the Y-axis direction is performed by, for example, entering light into the waveguide from one surface side of the first component 210, passing through the waveguide of the second component 220, and the first component 210. The amount of light emitted from the other surface is measured, and the second component 220 is moved in the Y-axis direction so that the amount of light is maximized.

  When the optimum position of the second component 220 with respect to the first component 210 is determined in this way, an optical adhesive is injected into the gap between the first component 210 and the second component 220 so that both are inserted. Join. Thereby, the alignment (optical coupling) between the first component 210 and the second component 220 is completed.

  As described above, in the present embodiment, the conductive patterns 211a, 211b, 221a, and 221b provided in a complementary manner to the first and second component parts 210 and 220 are used, and the continuity is checked by the conductivity meter 233 to obtain the second. Since the tilt angles θz and θx of the component 220 are adjusted, the tilt angles θz and θx can be adjusted easily and with high accuracy.

  It is also conceivable to adjust the tilt angles θz and θx of the second component 220 by bringing the entire second component 220 into contact with the smooth surface of the first component 210. However, in this case, warpage or deformation of the component parts 210 and 220, protrusions due to foreign matters, and the like may become obstacles, and the first component part 210 and the second component part 220 may not be optically coupled with high accuracy. .

  On the other hand, in the present embodiment, since the first component 210 and the second component 220 are aligned using only the vicinity of the edge, warpage and deformation of the components 210 and 220, protrusions due to foreign matters, and the like. Therefore, highly accurate alignment (optical coupling) becomes possible.

  Note that at least a part of the wiring patterns 211a, 211b, 221a, and 221b is made of a soft material such as a conductive paste in order to perform high-precision alignment even if the component parts are warped or deformed, and protrusions due to foreign matters. It is preferable to form by.

(Second Embodiment)
FIG. 8 is a perspective view showing an optical coupling method according to the second embodiment of the present invention.

  In the first embodiment, a conductive pattern extending in the width direction (X-axis direction) is formed on each of the first and second components, but in this embodiment, a conductive pattern extending in the length direction (Z-axis direction) is formed. Then, the tilt angles θx and θz are adjusted using the conductive patterns.

  That is, as shown in FIG. 8, the first component 250 is provided with a recess, and when the second component 260 is properly disposed in the recess, the first component 250 is guided. A waveguide (not shown) and a waveguide (not shown) of the second component 260 are optically coupled.

  The width of the first component 250 (length in the X-axis direction) is wider than the width of the second component 260 (length in the X-axis direction), and the width direction of the first component 250 At both end portions in the (X-axis direction), the width of the recess (the length in the Z-axis direction) is narrower than the width (the length in the Z-axis direction) of the portion where the second component 260 is disposed. In addition, two sets of conductive patterns 251a and 251b are formed on the hill portion at the end in the width direction (X-axis direction) of the first component 250, with the recess interposed therebetween. Here, as shown in FIG. 8, the conductive pattern 251a is a pair of patterns disposed on one end side (front side) with a recess interposed therebetween, and the conductive pattern 251b is the other end side (back side). It is a pair of pattern arrange | positioned on both sides of a recessed part.

  Conductive patterns 261a and 261b extending in the length direction (Z-axis direction) are provided at the end of the lower surface of the second component 260 in the width direction (X-axis direction). As shown in FIG. 8, the conductive pattern 261a is arranged on one end side (front side), and the conductive pattern 261b is arranged on the other end side (back side). The length of the conductive pattern 261a is set longer than the distance between the two conductive patterns 251a of the first component 250, and the length of the conductive pattern 261b is the distance between the two conductive patterns 251b of the first component 250. Is set longer than.

  The conductive pattern 251a and the conductive pattern 561a have a complementary relationship. When these conductive patterns 251a and 261a overlap in an optimal state, the two conductive patterns 251a are electrically connected. Similarly, the conductive pattern 251b and the conductive pattern 261b have a complementary relationship. When these conductive patterns 251b and 261b overlap in an optimal state, the two conductive patterns 251b are electrically connected. Is done.

  Also in the present embodiment, since the tilt angles θx and θz of the second component 260 are adjusted in the same manner as in the first embodiment, detailed description thereof is omitted here. However, in this embodiment, since the conductive patterns 252a and 251b and the conductive patterns 261a and 261b are arranged at both ends in the width direction (X-axis direction), the tilt angle θx is adjusted as shown in FIG. The point which adjusts tilt angle (theta) z differs from 1st Embodiment. 9 shows a side view when viewed from the direction indicated by the arrow B in FIG.

  Also in this embodiment, the same effect as that of the first embodiment can be obtained.

(Third embodiment)
FIG. 10 is a perspective view showing an optical coupling method according to the third embodiment of the present invention.

  The first component 310 is provided with a recess, and when the second component 320 is properly disposed in the recess, the waveguide (not shown) of the first component 310 and the second component 310 are arranged. A waveguide (not shown) of the component 320 is optically coupled.

  The width (the length in the X direction) of the first component 310 is longer than the width of the second component 320. Further, on one end side in the width direction of the first component 310 (front side in FIG. 10), the width of the recess (the length in the X-axis direction) is larger than the portion where the second component 320 is disposed. It is narrower. A pair of conductive patterns 311a are formed on the hill portion of the first component 310 with the narrowed recess interposed therebetween. Furthermore, a plurality of conductive patterns 311b are formed along the width direction (X-axis direction) on the hill portion near the edge of one edge (right edge in FIG. 10) of the recess of the first component 310. ing.

  A conductive pattern 321a extending in the length direction (Z-axis direction) is formed at one end portion (front side in FIG. 10) in the width direction (X-axis direction) of the lower surface of the second component 320. In addition, a plurality of conductive patterns 321b are formed along the width direction (X-axis direction) at one end (right side in FIG. 10) in the length direction (Z-axis direction) of the second component 320. Yes.

  The conductive pattern 311a of the first component 310 and the conductive pattern 321a of the second component 320 have a complementary relationship, and if these conductive patterns 311a and 321a overlap in an optimal state, the length One wiring is formed in the direction (Z-axis direction). Further, the conductive pattern 311b of the first component 310 and the conductive pattern 321b of the second component 320 have a complementary relationship, and when these conductive patterns 311b and 321b overlap in an optimal state, A single wiring is formed in the width direction (X-axis direction).

  In the present embodiment, as in the first embodiment, the first component 310 is placed on the fixed stage, and the second component 320 is held under the precision movement stage (see FIG. 4). ). Then, the position of the second component 320 is adjusted by the precision stage so that electricity is conducted to the conductive patterns 311a and 321a. When the conductive pattern 311a and the conductive pattern 321a overlap with each other without a gap, the value of the continuity meter changes. Thus, when the conductive pattern 311a and the conductive pattern 321a overlap with each other without a gap, it means that the tilt angle θx of the first component 310 and the tilt angle θx of the second component 320 coincide. In this state, the tilt angle θx of the second component 320 is fixed.

  Next, the position of the second component 320 is adjusted by the precision stage so that electricity is conducted to the conductive patterns 311b and 321b. When the conductive pattern 311b and the conductive pattern 321b overlap with each other without a gap, the value of the continuity meter changes. As described above, when the conductive pattern 311b and the conductive pattern 321b overlap with each other without a gap, it means that the tilt angle θz of the first component 310 and the tilt angle θz of the second component 320 match. In this state, the tilt angle θz of the second component is fixed.

  Thus, in this embodiment, the tilt angles θx and θz of the second component 320 are adjusted. In the present embodiment, the tilt angle θz is adjusted after the tilt angle θx is adjusted. However, the tilt angle θx may be adjusted after the tilt angle θz is adjusted.

  Also in this embodiment, the same effect as that of the first embodiment can be obtained.

(Optical device manufacturing method)
A method for manufacturing an optical device (optical switch) to which the present invention is applied will be described below.

  FIG. 11A is a plan view showing the optical switch, and FIG. 11B is a cross-sectional view taken along the line II-II in FIG.

  The optical switch includes an incident side optical waveguide unit 401, a collimating unit 402, an incident side optical deflection element unit 403, a common waveguide 404, an output side optical deflection element unit 405, a light collecting unit 406, and an output side optical waveguide unit 407. Has been. The incident side optical waveguide portion 401, the collimating portion 402, the common waveguide 404, the condensing portion 406, and the emission side optical waveguide portion 407 are formed by stacking optical films on the substrate 400. In addition, the incident-side light deflection element unit 403 and the emission-side light deflection element unit 405 are mounted on the substrate 400 after being formed using a material exhibiting an electro-optic effect.

  The incident-side optical waveguide section 401 covers n optical waveguides (core layers) 401a (in the example shown in FIG. 11, n = 4) and these optical waveguides 401a, and guides an optical signal by a difference in refractive index. The clad layer 401b is confined in the waveguide 401a. Similarly, the output side optical waveguide section 407 includes a plurality of optical waveguides (core layers) 407a and a clad layer that covers these optical waveguides 407a and confines an optical signal in the optical waveguide 407a due to a difference in refractive index. 407b.

  The collimator unit 402 includes n sets of collimator lenses 402a. These collimating lenses 402a are formed by patterning a core layer and a cladding layer sandwiching the core layer from above and below in a predetermined shape. The light emitted from the optical waveguide 401a spreads radially, but becomes collimated light by the collimating lens 402a.

  The incident-side light deflection element section 403 is provided with n sets of light deflection elements 403a. A wedge-shaped lower electrode is formed below each optical deflection element 403a, and an upper electrode common to each optical deflection element 403a is formed above. When a voltage is applied between the lower electrode and the upper electrode, the propagation direction of the optical signal is changed by the electro-optic effect. In this example, four light deflecting elements 403a are arranged for each transmission path by alternately changing the directions of the wedge-shaped electrodes along the transmission path.

  The common waveguide 404 is configured by a slab waveguide including a thin film core layer and a clad layer sandwiching the core layer from above and below. A plurality of optical signals output from the incident-side optical deflecting element unit 403 pass through the common waveguide 404 at the same time, but these optical signals travel straight in a predetermined direction in the common waveguide 404, so that other light signals The light is transmitted to the output side light deflection element unit 405 without interfering with the signal.

  The exit side light deflection element section 405 is provided with m pairs (m = 4 in the example shown in FIG. 11) of light deflection elements 405a. These light deflecting elements 405a deflect the light that has reached the light deflecting element 405a through the common waveguide 404 in a direction parallel to the optical waveguide 407a. The emission side light deflection element unit 405 has the same structure as the incident side light deflection element unit 403.

  The condensing unit 406 includes m sets of condensing lenses 406a. Similar to the collimating lens 403a, these condensing lenses 406a are also formed by patterning a core layer and a cladding layer sandwiching the core layer from above and below in a predetermined shape. These condensing lenses 406 a have a function of condensing the light that has passed through the light deflection element 405 a and guiding it to the optical waveguide 407.

  As shown in FIG. 11A, both sides of the concave portion where the incident side light deflection element portion 403 and the emission side light deflection element portion 405 are arranged are narrower than the portion where the deflection element portions 403 and 405 are arranged. Conductive patterns 408a, 408b, 408c, and 408d are formed with the recesses interposed therebetween. Conductive patterns 409 a, 409 b, 409 c, and 409 d extending in the length direction are formed on the edge portions in the width direction on the lower surface side of the incident side light deflection element portion 403 and the emission side light deflection element portion 405, respectively. The conductive pattern 408a and the conductive pattern 409a have a complementary relationship as described in the second embodiment. Similarly, the conductive pattern 408b and the conductive pattern 409b have a complementary relationship, the conductive pattern 408c and the conductive pattern 409c have a complementary relationship, and the conductive pattern 408d and the conductive pattern 409d are complementary. Have a relationship.

  Hereinafter, a method for manufacturing the optical switch shown in FIGS. 11A and 11B will be described with reference to FIGS.

  First, with reference to FIGS. 12A to 12C, a method of forming the incident side optical deflection element portion 403 will be described. Since the exit side light deflection element section 405 is also formed by the same method as the entrance side light deflection element section 403, description of the method of forming the exit side light deflection element section 405 is omitted here. In addition, the light deflection element portion 405 is mounted on the substrate 400 with the surface on which the wedge-shaped lower electrode is formed facing down. In FIGS. 12A to 12C, for convenience, the surface on which the lower electrode is formed. On the top.

As shown in FIG. 12A, an SrTiO ₃ substrate 411 doped with Nb (niobium) to provide conductivity is prepared, and a first cladding layer (upper cladding layer) is formed on the SrTiO ₃ substrate 411. 412 and to for example _{PLZT (Pb x La 1-x} (Zr y Ti 1-y O 3): where, 0 <x <1,0 <y <1)) film, a sol-gel method, PLD (pulsed laser deposition) method Alternatively, it is formed by MOCVD (metal organic chemical vapor deposition) method or the like. Note that the SrTiO ₃ substrate 411 serves as an upper electrode common to the respective light deflection elements 403a.

Next, as shown in FIG. 12B, a core layer 413 is formed on the first cladding layer 412 as a core layer 413, which has a refractive index higher than that of the cladding layer 412 and exhibits an electrooptic effect, for example, PZT (Pb (Zr _{y Ti 1-y O 3)} , where, 0 <y <1) a sol-gel method, is formed to a thickness of, for example, 3~5μm by PLD or MOCVD method. The core layer 413 may be formed of PLZT having a higher refractive index than the first cladding layer 412.

  Next, as shown in FIG. 12C, a PLZT film having the same composition as the first cladding layer 412 is formed on the core layer 413 as the second cladding layer (lower cladding layer) 414, for example. Thereafter, for example, Au (gold) or the like is sputtered on the second clad layer 414 to form a conductor film having a thickness of about 200 nm. Then, this conductor film is patterned by a photolithography method to form wedge-shaped lower electrodes 415, conductive patterns 408a and 408b (see FIG. 11A), and alignment marks (not shown).

  In this manner, the first clad layer 412, the core layer 413, the second clad layer 414, the lower electrode 415, the conductive patterns 408a and 408b, and the like are formed on the substrate 411, and then processed into a predetermined size by polishing. To do. Thereby, the incident side optical deflection element part 403 is completed. Further, the emission side optical deflection element portion 405 is formed by the same method.

  Next, with reference to FIGS. 13A to 13E, a method for forming the incident-side optical waveguide portion 401, the collimating portion 402, the common waveguide portion 404, the condensing portion 406, and the emission-side optical waveguide portion 406 will be described. To do.

  First, as shown in FIG. 13A, a substrate 400 is prepared. In this embodiment, a silicon substrate is used as the substrate 400.

  Next, as shown in FIG. 13B, a quartz (silica) -based material is deposited on the substrate 400 by the MOCVD method to form the lower cladding layer 421 and the core layer 422. Then, the core layer 422 of the input side optical waveguide portion 401 and the output side optical waveguide portion 407 is patterned by RIE (reactive ion etching) to form optical waveguides 401a and 407a (see FIG. 11A).

  Next, as shown in FIG. 13C, a quartz-based material is deposited on the substrate 400 by the MOCVD method to form the upper cladding layer 423. Note that the lower clad layer 421, the core layer 422, and the upper clad layer 423 may be formed of a polymer material.

  Next, as shown in FIG. 13D, the upper cladding layer 423, the core layer 422, and the lower cladding layer 421 are etched by the RIE method to form the recesses 424 for mounting the optical deflection element portions 403 and 405. The collimator lens 402a of the collimator lens unit 402 and the condensing lens 306a of the condensing unit 306 are formed. In addition, as described above, the recess 424 has a width at both ends in the X direction (length in the Z-axis direction) narrower than the length of the light deflection element portions 403 and 405 (length in the Z-axis direction). It is necessary to keep.

  Thereafter, after forming an Au film to a thickness of about 200 nm by sputtering, the Au film is patterned by photolithography, and further the thickness is made 3 to 5 μm by plating, so that the incident side light deflection element 403 is formed. And a wiring pattern (not shown) for supplying power to the lower electrode of the output side light deflection element 405, conductive patterns 408a, 408b, 408c, 408d (see FIG. 11 (a)), and an alignment mark (not shown). Form.

  In this way, the substrate 400 having the input-side optical waveguide portion 401, the collimating portion 402, the common waveguide portion 404, the condensing portion 406, and the emission-side optical waveguide portion 407, and the light deflection element portions 403 and 405 are individually provided. After the formation, alignment is performed by the method described in the second embodiment, and the light deflection element units 403 and 405 are mounted on the substrate 400. As a result, the optical switch shown in FIGS. 11A and 11B is completed.

  Hereinafter, various aspects of the present invention will be collectively described as supplementary notes.

(Additional remark 1) In the optical coupling method which optically couples the 1st optical member and the 2nd optical member,
The inclination of the second optical member with respect to the first optical member is corrected by abutting the surface near the edge of the second optical member against the surface near the edge of the first optical member. Optical coupling method.

(Appendix 2) Forming a plurality of first conductive patterns spaced from each other in the vicinity of the edge of the upper surface of the first optical member,
Forming a second conductive pattern having a complementary relationship to the first conductive pattern in the vicinity of the edge of the lower surface of the second optical member;
A portion near the edge of the lower surface of the second optical member is abutted against a portion near the edge of the upper surface of the first optical member, and the second conductive pattern causes a space between the plurality of first conductive patterns. Adjusting the angle of the second optical member to be electrically connected;
The second optical member is disposed at a predetermined position with the angle of the second optical member adjusted, and the first optical member and the second optical member are fixed. Optical coupling method.

  (Supplementary note 3) The optical coupling method according to supplementary note 2, wherein at least a part of the first conductive pattern and the second conductive pattern is formed of a soft material.

(Additional remark 4) The 1st optical member is provided with the crevice which arranges the 2nd optical member, and the 1st conductive pattern is formed near two edges which the crevice mutually counters, respectively,
The optical coupling method according to claim 2, wherein the second conductive pattern is formed in the vicinity of two edges facing each other on the lower surface of the second optical member.

(Supplementary Note 5) The second conductive pattern formed in the vicinity of one edge of the lower surface of the second optical member is the first conductive pattern formed in the vicinity of one edge of the concave portion of the first optical member. Adjusting the first angle of the second optical member to be electrically connected to one conductive pattern;
The second conductive pattern formed in the vicinity of the other edge of the lower surface of the second optical member is replaced with the first conductive pattern formed in the vicinity of the other edge of the concave portion of the first optical member. The optical coupling method according to appendix 4, wherein the second optical member is moved so as to be electrically connected to the second optical member to adjust a second angle of the second optical member.

(Additional remark 6) The 1st optical member is provided with the crevice which arranges the 2nd optical member, and the 1st conductive pattern is formed in the neighborhood of two adjacent edges of the crevice, respectively.
The optical coupling method according to appendix 2, wherein the second conductive pattern is formed on the lower surface of the second optical member in the vicinity of two adjacent edges.

(Supplementary Note 7) The second conductive pattern formed in the vicinity of one edge of the lower surface of the second optical member is the first conductive pattern formed in the vicinity of one edge of the concave portion of the first optical member. Adjusting the first angle of the second optical member to be electrically connected to one conductive pattern;
The second conductive pattern formed in the vicinity of the other edge of the lower surface of the second optical member is replaced with the first conductive pattern formed in the vicinity of the other edge of the concave portion of the first optical member. 7. The optical coupling method according to appendix 6, wherein the second optical member is moved so as to be electrically connected to the second optical member to adjust a second angle of the second optical member.

  (Supplementary note 8) The optical coupling method according to supplementary note 2, wherein a slab waveguide is formed in the first optical member.

FIG. 1A is a plan view showing an optical switch, and FIG. 1B is a cross-sectional view taken along line I-I in FIG. FIG. 2 is a schematic diagram illustrating a horizontal direction (X-axis direction and Z-axis direction) and a rotation direction (θx direction, θy direction, and θz). FIG. 3 is a perspective view showing an optical coupling method according to the first embodiment of the present invention. FIG. 4 is a diagram (No. 1) showing a method for adjusting the tilt angles θx and θz. FIG. 5 is a diagram (No. 2) showing a method for adjusting the tilt angles θx and θz. FIG. 6 is a view (No. 3) showing a method for adjusting the tilt angles θx and θz. FIG. 7 is a view (No. 4) showing a method for adjusting the tilt angles θx and θz. FIG. 8 is a perspective view showing an optical coupling method according to the second embodiment of the present invention. FIG. 9 shows a side view as seen from the direction indicated by arrow B in FIG. FIG. 10 is a perspective view showing an optical coupling method according to the third embodiment of the present invention. 11 (a) and 11 (b) are diagrams showing a method of manufacturing an optical device (optical switch) to which the present invention is applied, FIG. 11 (a) is a plan view showing the optical switch, and FIG. 11 (b) is a diagram. It is sectional drawing by the II-II line of 11 (a). 12A to 12C are cross-sectional views showing a method of forming the incident side optical deflection element portion. 13A to 13E illustrate a method of forming the incident side optical waveguide portion, the collimating portion, the common waveguide portion, the condensing portion, and the emission side optical waveguide portion.

Explanation of symbols

100, 400 ... substrate,
101, 107, 401, 407 ... optical waveguide part,
101a, 107a, 401a, 407a ... optical waveguide,
101b, 107b, 401b, 407b ... clad layer,
102, 402 ... collimating part,
102a, 402a ... collimating lens,
103, 105, 403, 405... Optical deflection element unit,
103a, 105a, 403a, 405a ... light deflection element,
104, 404 ... common waveguide,
106, 406...
106a, 407a ... Condensing lens,
210, 250, 310 ... first components,
211a, 211b, 221a, 221b, 251a, 251b, 261a, 261b, 311a, 311b, 321a, 321b, 408a, 408b, 408c, 408d, 409a, 409b, 409c, 409d ... conductive pattern,
220, 260, 320 ... second components,
230 ... a fixed stage,
231... Control unit,
232 ... a moving stage,
233 ... a continuity meter.

Claims (3)

Forming a plurality of first conductive patterns spaced from each other in the vicinity of the edge of the upper surface of the first optical member;
Forming a second conductive pattern having a complementary relationship to the first conductive pattern in the vicinity of the edge of the lower surface of the second optical member;
A portion near the edge of the lower surface of the second optical member is abutted against a portion near the edge of the upper surface of the first optical member, and the second conductive pattern causes a space between the plurality of first conductive patterns. Adjusting the angle of the second optical member to be electrically connected;
The second optical member is disposed at a predetermined position with the angle of the second optical member adjusted, and the first optical member and the second optical member are fixed. Optical coupling method. The first optical member is provided with a recess for disposing the second optical member, and the first conductive pattern is formed in the vicinity of two edges of the recess facing each other,
2. The optical coupling method according to claim 1, wherein the second conductive pattern is formed in the vicinity of two edges facing each other on a lower surface of the second optical member. The first optical member is provided with a recess for disposing the second optical member, and the first conductive pattern is formed in the vicinity of two adjacent edges of the recess,
2. The optical coupling method according to claim 1, wherein the second conductive pattern is formed in the vicinity of two edges adjacent to each other on the lower surface of the second optical member.

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