JP3464039B2 - Optical device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical device, and more particularly to an optical device characterized by distribution of optical signals.

[0002]

2. Description of the Related Art Conventionally, when a plurality of 1-chip microcomputers (hereinafter referred to as 1-chip microcomputers) are used to process a logical operation in parallel, each 1-chip microcomputer has to be synchronized in order to synchronize the operation of these 1-chip microcomputers. An electric signal for a clock is input. However, when the number of 1-chip microcomputers used for parallel processing increases, the wiring structure for supplying the clock electrical signal becomes complicated, or crosstalk between the wirings increases.
Therefore, an apparatus has been proposed in which an optical signal is used as a clock signal instead of an electric signal.

As an apparatus of this kind, for example, a document: PROC
EEDINGS OF THE IEEE, VOL.72, NO.7, JULY 1984 pp.850〜
866, page 860, which is disclosed in FIG. In this conventional device, a plurality of 1-chip microcomputers are arranged in an array, and between the 1-chip microcomputers and the optical signal source,
Insert the hologram plate. Each one-chip microcomputer has a light receiving element. A free space is interposed between the optical signal source and the hologram plate, and the optical signal for the clock emitted from the optical signal source is spread in a conical shape and then incident on the hologram plate. The hologram plate spatially divides an optical signal spread in a conical shape for each one-chip microcomputer that performs parallel processing,
The divided optical signal is condensed on the light receiving element of the one-chip microcomputer.

[0004]

However, in the above-mentioned conventional apparatus, in order to spread the optical signal in a conical shape, it is necessary to increase the distance between the optical signal source and the hologram plate as the light distributing means, which is saved. It was a hindrance to space.

An object of the present invention is to solve the above-mentioned conventional problems and to provide an optical device which can save space more than ever before.

[0006]

In order to achieve this object, an optical device of the present invention is provided with a planar light distribution waveguide and a light distribution waveguide, which intersects with the light guiding direction of the light distribution waveguide. A first diffraction grating that diffracts an optical signal that is incident from a first direction in the optical distribution direction of the optical distribution waveguide and couples the optical signal to the optical distribution waveguide; and the optical distribution waveguide that is provided in the optical distribution waveguide. And a second diffraction grating for diffracting the optical signal guided by the light in the second direction intersecting the optical waveguide direction of the optical distribution waveguide and for emitting the light from the optical distribution waveguide. A diffraction grating for diffracting an optical signal radially when viewed from one direction, wherein a plurality of second diffraction gratings are discretely arranged in a waveguide region of the radially diffracted optical signal. .

[0007]

According to this structure, the first diffraction grating allows the optical signal from the optical component corresponding to the diffraction grating to enter from the first direction intersecting the optical waveguide direction of the optical distribution waveguide, This optical signal is diffracted in the optical waveguide direction of the optical distribution waveguide and is coupled to the optical distribution waveguide. Moreover, the first diffraction grating diffracts the optical signal radially when viewed from the first direction.

Therefore, the optical signal propagates in the optical distribution waveguide while radiating from the first diffraction grating. As a result, the waveguide region of the optical signal in the optical distribution waveguide becomes a planar region that spreads radially. Such an optical signal guiding region can be formed even if the distance between the first diffraction grating and the optical component is shortened.

Further, since the plurality of second diffraction gratings are discretely arranged in the radial optical signal waveguide region, the optical signal can be made incident on each of these second diffraction gratings. Therefore, the optical signal can be distributed to the optical components corresponding to the respective second diffraction gratings.

Further, the optical signal from the optical component corresponding to the second diffraction grating can be made incident on the optical component corresponding to the first diffraction grating by the principle of reversing the optical path.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. It should be noted that the drawings are merely schematic representations so that the invention can be understood, and therefore the invention is not limited to the illustrated examples.

FIG. 1 is a perspective view schematically showing the overall construction of the first embodiment of the present invention. FIG. 2 is a cross-sectional view schematically showing the structure of the main part of the first embodiment, showing an enlarged cross-section of the main part taken along the line II-II in FIG.

As shown in these figures, the optical device 10 of this embodiment is provided with a planar light distribution waveguide 12 and the light distribution waveguide 12 and intersects the light guiding direction of the light distribution waveguide 12. A first diffraction grating 14 that diffracts an optical signal that has entered from a first direction in the optical waveguide direction of the optical distribution waveguide 12 and couples the optical signal to the optical distribution waveguide 12; A second diffraction grating 1 which diffracts an optical signal guided through the distribution waveguide 12 in a second direction intersecting with the optical waveguide direction of the optical distribution waveguide 12 and emits it from the optical distribution waveguide 12.
6 and 6. The first diffraction grating 14 is a diffraction grating that diffracts the optical signal radially when viewed from the first direction, and a plurality of second diffraction gratings 16 are provided in the waveguide region of the radially diffracted optical signal. It is placed discretely.

In this embodiment, the light distribution waveguide 12 is a planar slab waveguide or a planar type waveguide having a waveguide mode with respect to the optical signal wavelength λ. One surface 18 of the insulating GaAs substrate 18
It is provided in a. The light distribution waveguide 12 extends in a plane along the substrate surface 18a, so that the light guiding direction of the light distribution waveguide 12 can be a two-dimensional direction substantially along the substrate surface 18a.

The waveguide structure may be either a multi-layer structure or a single-layer structure, but here, the Al _0.3 Ga _0.7 As first cladding layer 12a and GaA sequentially provided on the substrate surface 18a are used.
The s light guide layer 12b and the Al _0.3 Ga _0.7 As second cladding layer 12c constitute a light distribution waveguide 12 having a three-layer structure. The thickness of the light guide layer 12b is about 0.2 μm, and the thickness of the cladding layers 12a and 12c is 0.5 to 1.
It is about 0 μm.

Further, the shape of the light distribution waveguide 12 as viewed from the direction normal to the substrate surface 18a is any suitable shape having a two-dimensional spread (spread in the two-dimensional direction). The two-dimensional expansion of the light distribution waveguide 12 has a width sufficient for arranging the first diffraction grating 14 and the second diffraction grating 16 in a two-dimensional manner, particularly for arranging in a plurality of rows and a plurality of columns. Have. Here, the light distribution waveguide 12 is provided over the entire substrate surface 18a, and the light distribution waveguide 1 viewed from the normal direction of the substrate surface 18a
The shape of 2 is rectangular.

The first diffraction grating 14 and the second diffraction grating 16 are arranged in an array in the two-dimensional direction and provided on the light distribution waveguide 12. Here, one first diffraction grating 14 and 8
The second diffraction gratings 16 are arranged in 3 rows and 3 columns.

The first diffraction grating 14 comprises concave portions 14a and convex portions 14b which are alternately and repeatedly provided along the optical waveguide direction of the light distribution waveguide 12. The first diffraction grating 14 is a second-order diffraction grating for the optical signal wavelength λ, and the first direction, that is, the optical signal incident direction to the first diffraction grating 14 is the substrate surface of the substrate 18 provided with the optical distribution waveguide 12. The normal direction is 18a. Therefore, from the direction normal to the substrate surface 18a, the first diffraction grating 1
4 can be diffracted in the optical waveguide direction of the optical distribution waveguide 12, here in the direction substantially along the substrate surface 18a, so that the optical signal can be coupled to the optical distribution waveguide 12. For example, the optical signal wavelength λ is 0.98 μm, and the effective refractive index n of the optical distribution waveguide 12 is 3.3636.
, The period Λ of the first diffraction grating 14 is Λ = λ / n
= About 291.35 nm, 2 for the optical signal wavelength λ
The following first diffraction grating 14 can be constructed.

The location of the first diffraction grating 14 may be any suitable location where the optical signal can be diffracted and coupled to the light distribution waveguide 12, but here, it is provided on the surface of the second cladding layer 12c. One diffraction grating 14 is provided.

Further, the concave portions 14a and the convex portions 14b as viewed from the direction normal to the substrate surface 18a have a circular shape, and the concave portions 1
4a and the convex portion 14b are arranged in a concentric pattern centered on the axis O when viewed from the normal direction of the substrate surface 18a. The axis O is an axis that intersects the light distribution waveguide 12 and is parallel to the normal line of the substrate surface 18a. The radii of the concave portions 14a and the convex portions 14b, which are arranged concentrically alternately, are different in the arrangement order. By arranging the circular concave portions 14a and convex portions 14b concentrically in this manner, the optical signal incident on the first diffraction grating 14 is reflected by the axis O.
Can be radially diffracted around. As a method of forming the concentric circular first diffraction grating 14, for example, the literature:
Applied Physics Letters 60 (16), 20 April 1992 pp.19
The electron beam writing method and the reactive ion etching method can be used as disclosed in pages 1991, 21 to 1993, bottom left column, lines 1 to 7.

The second diffraction grating 16 is composed of concave portions 16a and convex portions 16b which are alternately and repeatedly provided along the optical waveguide direction of the light distribution waveguide 12. The second diffraction grating 16 is a second-order diffraction grating with respect to the optical signal wavelength λ, and the second direction, that is, the optical signal emission direction from the second diffraction grating 16 is the substrate surface of the substrate 18 provided with the optical distribution waveguide 12. The normal direction is 18a. Therefore, the optical signal guided through the optical distribution waveguide 12 and incident on the second diffraction grating 16 can be diffracted in the normal direction of the substrate surface 18a, so that the optical signal can be transmitted.
Can be emitted from. For example, the optical signal wavelength λ is 0.98 μm, and the effective refractive index n of the optical distribution waveguide 12 is
Is 3.3636, the period Λ of the second diffraction grating 16 is
If Λ = λ / n = about 291.35 nm, the second-order second diffraction grating 16 can be configured for the optical signal wavelength λ. Here, the period Λ of the first diffraction grating 14 and the second diffraction grating 16
Are equal.

The location of the second diffraction grating 16 may be any suitable location where the optical signal can be diffracted and emitted from the light distribution waveguide 12, but here, it is provided on the surface of the second cladding layer 12c. Two diffraction gratings 16 are provided.

Further, the shapes of the concave portions 16a and the convex portions 16b as viewed from the direction normal to the substrate surface 18a are circular arcs, and these concave portions 1
6a and the convex portion 16b are arranged in a concentric pattern with the axis O as the center when viewed from the direction normal to the substrate surface 18a. Therefore, the shapes of the concave portions 16a and the convex portions 16b are arranged in a concentric pattern with an arc O as a center of curvature obtained by cutting a part of a concentric circle centered on the axis O when viewed from the normal direction of the substrate surface 18a. It is a circular arc. As a method of forming such a second diffraction grating 16, as in the case of the first diffraction grating 14, for example, an electron beam drawing method and a reactive ion etching method can be used.

Furthermore, the optical device 10 of this embodiment includes a first optical component 20 for emitting a light signal to the first diffraction grating 14, double
A number of second diffraction gratings 16 respectively enter optical signals,
Are arranged at positions corresponding to the respective second diffraction gratings 16.
The second optical component 22 is provided.

In this embodiment, the first optical component 20 and the plurality of second optical components 22 are provided on the substrate 1 provided with the optical distribution waveguide 12.
8 is provided on the other substrate surface 18b. The other board surface 18
b and one substrate surface 18a are substantially parallel to each other. Then, the first optical component 20 and the second optical component 22 are arranged in an array in a two-dimensional direction, and the first optical component 20 is arranged at a position corresponding to the first optical diffraction grating 14 and the second optical component 22 is arranged in a second position. It is arranged at a position corresponding to the two-light diffraction grating 16. Here, the number of the first optical components 20 and the number of the first optical diffraction gratings 14 provided are the same,
The second optical component 22 and the second optical diffraction grating 16 are provided in the same number.

The first optical component 20 and the plurality of second optical components 22 provided on the other substrate surface 18b are individually divided chip components.

The first optical component 20 is an OEIC (optical electronic integrated circuit) in which an electric circuit 20a for generating an electric signal and a light emitting element 20b for emitting an optical signal based on the electric signal from the electric circuit 20a are monolithically integrated. Is. In the figure,
The portion of the first optical component 20 not marked with dots is the electric circuit 20.
The light emitting element 20b is indicated by a and the dotted portion is indicated by a.
For example, the electric circuit 20a may be a GaAs IC and a light emitting element 2
0b is an InGaAs surface emitting laser. InGa
As an As-based surface-emitting laser, for example, a document: IEEE JOU
RNAL OF QUANTUM ELECTRONICS, VOL.27, NO.6, JUNE 1991
pp.1359-1367, page 1360, FIG.

The light emitting surface 20b1 of the light emitting element 20b
The light emitting surface 20b1 is positioned with respect to the first diffraction grating 14 so that the optical signal emitted from At this time, the optical signal emitted from the light emitting surface 20b1 is moved from the direction in which the axis O is substantially the center axis from the first diffraction grating 1
Positioning is preferably such that it is incident at 4.

If the area of the first diffraction grating 14 is set to be several times as large as the area of the light emitting surface 20b1 when viewed from the direction normal to the substrate surface 18a, the light distribution and guiding of the optical signal emitted from the light emitting surface 20b1 is performed. The coupling loss to the waveguide 12 can be reduced.

The second optical component 22 is an OEIC in which a light receiving element 22a for converting an optical signal into an electric signal and an electric circuit 22b which operates based on the electric signal from the light receiving element 22a are monolithically integrated. In the figure, the dotted portion of the second optical component 22 is the light receiving element 22a, and the undotted portion is the electric circuit 22b. For example, the light receiving element 2
2a is an InGaAs PIN photodiode and the electric circuit 22b is a GaAs IC. InGaAs PI
As the N photodiode, for example, the one in which a GaAs substrate is used in the structure disclosed in FIG. 6.7, page 372, published in 1984 by Hiroo Yonezu, "Optical Communication Device Optics", Engineering Book Co., Ltd. , Can be used.

Then, the optical signal from the second diffraction grating 16 is made incident on the light incident surface 22a1 of the light receiving element 22a,
The light incident surface 22a1 is positioned with respect to the second diffraction grating 16.

When the area of the second diffraction grating 16 is set to be approximately the same as the area of the light incident surface 22a1 when viewed from the direction normal to the substrate surface 18a, an optical signal of a sufficient light amount for operating the light receiving element 22a. Can be incident on the light incident surface 22a1.

The substrate 18 is interposed between the light emitting element 20b and the first diffraction grating 14, and therefore the signal light emitted from the light emitting element 20b passes through the substrate 18 and the first diffraction grating 1
It is incident on 4. Similarly, the light receiving element 22 and the second diffraction grating 1
The substrate 18 is interposed between the second diffraction grating 1 and the second diffraction grating 1.
The optical signal diffracted by 6 passes through the substrate 18 and enters the light receiving element 22a.

Therefore, in order to reduce the propagation loss of the optical signal,
The optical signal wavelength λ is preferably transparent to the substrate 18. Therefore, the energy gap of the compound semiconductor forming the light emitting element 20b is made smaller than the energy gap of the compound semiconductor forming the substrate 18. For example, if the energy gap of the active layer is determined so that the emission wavelength λ of the light emitting element 20b is 0.98 μm, the absorption coefficient of the semi-insulating GaAs substrate 18 for the emission wavelength λ, that is, the optical signal wavelength λ, can be significantly reduced. Therefore, the optical signal wavelength λ can be a wavelength transparent to the substrate 18.

In the optical device 10 of this embodiment configured as described above, the optical signal emitted from the light emitting element 20b in the direction normal to the substrate surface 18a passes through the substrate 18 and passes through the first diffraction grating 14a. Incident on. Then, the optical signal is diffracted (deflected) in the direction along the substrate surface 18 a by the first diffraction grating 14 and is coupled to the light distribution waveguide 12, and the light distribution waveguide 1
2 is guided and is incident on the second diffraction grating 16. Then, the optical signal is diffracted (deflected) in the direction normal to the substrate surface 18a by the second diffraction grating 16, passes through the substrate 18, and is incident on the light receiving element 22a.

FIG. 3 is a diagram for explaining the optical signal distribution in the first embodiment. In the figure, the first diffraction grating 14 and the second diffraction grating 16 are mainly shown when viewed in the direction from the other substrate surface 18b to the one substrate surface 18a along the direction normal to the substrate surface 18a.

As shown in the figure, since the concave portion 14a and the convex portion 14b of the first diffraction grating 14 are circular in this embodiment, the optical signal L incident on the first diffraction grating 14 is
It is possible to perform radial diffraction over the entire 360 ° around the axis O when viewed from the direction normal to the substrate surface 18a. Therefore, when the region 24 in which the optical signal L is guided through the optical distribution waveguide 12 (hereinafter referred to as the waveguide region 24 of the optical signal L) is viewed from the normal direction of the substrate surface 18a, a radial pattern is provided over the entire 360 ° around the axis O. It can be a region, that is, a region over the entire surface of the light distribution waveguide 12. In the figure, the optical signal L is shown by an outline arrow.

By disposing a plurality of second diffraction gratings 16 in a discrete manner in the waveguide region 24 of the optical signal L, the optical signal L incident on the first diffraction grating 14 is transmitted to each of the second diffraction gratings 16. Can be distributed to.

As a form of use of the optical device 10 of this embodiment, for example, a clock signal generated by the first optical component 20 is supplied to a plurality of second optical components 22, and each second optical component 22 is based on the clock signal. Consider a case where logical operations are performed in synchronization with each other. In this case, the electric circuit 20 of the first optical component 20
a supplies an electric signal to the light emitting element 20b, and based on the electric signal, the light emitting element 20b emits an optical signal L for clock to the first diffraction grating 14. The optical signal L passes through the first diffraction grating 14, the light distribution waveguide 12 and the second diffraction grating 16,
It is incident on each second optical component 22. The light receiving element 22a of the second optical component 22 converts the optical signal L for clock into an electrical signal for clock, and performs logical operation processing based on this electrical signal for clock.

FIGS. 4 and 5 are diagrams for explaining modified examples of the first diffraction grating. In these diagrams, the substrate surface 1 is used.
The first diffraction grating 14 and the second diffraction grating 16 are mainly shown when seen from the other substrate surface 18b toward the one substrate surface 18a along the normal direction of 8a. In the description of these modified examples, points different from the first embodiment will be mainly described, and detailed description of the same points as the first embodiment will be omitted.

In the modification of the first diffraction grating 14 shown in FIG. 4, the shapes of the concave portions 14a and the convex portions 14b viewed from the normal direction of the substrate surface 18a are arcs, and the concave portions 14a and the convex portions 14b are formed on the substrate surface 18a. Are arranged in concentric circles centered on the axis O as viewed in the normal direction. Therefore, the shapes of the concave portions 14a and the convex portions 14b are arranged in concentric circles with the axis O as a center of curvature, which is an arc obtained by cutting a part of a concentric circle having the axis O as the center when viewed from the normal direction of the substrate surface 18a. It is a circular arc.

In this case, the waveguide region 24 of the optical signal L is a fan-shaped region centered on the axis O when viewed from the direction normal to the substrate surface 18a, and each fan-shaped waveguide region 24 has a second diffraction grating. 16 are arranged.

In the modification of FIG. 4, the shape of the concave portion 14a and the convex portion 14b of the first diffraction grating 14 is an arc which is not divided, but the first diffraction grating 14 shown in FIG.
In the modified example, the concave portion 1 viewed from the direction normal to the substrate surface 18a
The shapes of 4a and the convex portion 14b are divided into plural arcs, for example, three arcs, and the concave portion 14a and the convex portion 14 are
b are arranged in concentric circles with the axis O as the center when viewed from the direction normal to the substrate surface 18a. Therefore, the shapes of the concave portions 14a and the convex portions 14b are arcs arranged concentrically with the axis O as the center of curvature when viewed from the normal direction of the substrate surface 18a.

In this case, the first diffraction grating 14 is composed of the same number of arc-shaped diffraction gratings as the number of divisions of the arc, here three arc-shaped diffraction gratings 141, 142 and 143. The waveguide regions 24 of the optical signal L are generated corresponding to the respective arc-shaped diffraction gratings that form the first diffraction grating 14, and therefore, the same number of regions as the number of divisions of the circular arcs, here, three waveguide regions 241, 242. And 24
3 occurs. The shape of each of the waveguide regions 241 to 243 is also a fan-shaped region centered on the axis O when viewed from the normal direction of the substrate surface 18a, and the fan-shaped waveguide regions 241 to 243.
The second diffraction grating 16 is arranged in each of the.

FIG. 6 is a diagram for explaining a modified example of the second diffraction grating. In this figure, from the other substrate surface 18b to one substrate surface 18 along the direction normal to the substrate surface 18a.
The first diffraction grating 14 and the second diffraction grating 16 are mainly shown when viewed in the direction toward a. In the description of this modification, the points that are different from the first embodiment will be mainly described, and the detailed description of the same points as the first embodiment will be omitted.

In the modified example of the second diffraction grating 16 shown in FIG. 6, the shapes of the concave portions 16a and the convex portions 16b as viewed from the direction normal to the substrate surface 18a are line segments. Preferably, the concave portions 16a and the convex portions 16b are line segments parallel to a tangent line of a circle centered on the axis O when viewed from the normal direction of the substrate surface 18a.

FIG. 7 is a perspective view schematically showing the overall construction of the second embodiment of the present invention. In the description of the second embodiment, mainly the points different from the first embodiment will be omitted, and the detailed description of the same points as the first embodiment will be omitted.

In this embodiment, the electric circuit 20a of the first optical component 20 is formed on the other substrate surface 18b of the substrate 18 on which the light distribution waveguide 12 is provided, and the light emitting element 20b is separated from this electric circuit 20a. Use as chip parts. Furthermore, the second optical component 2
Substrate 1 in which the optical circuit 22b of 2 is provided with the optical distribution waveguide 12
The light receiving element 22a is formed on the other substrate surface 18b of No. 8 and is a chip component different from the electric circuit 22b.

The light emitting element 20b is connected to the first diffraction grating 14
And the light receiving element 22a is arranged at a position facing the second diffraction grating 16. Further, the electric circuits 20a and 22b are monolithically integrated on the other substrate surface 18b. The positions where these circuits 20a and 22b are arranged can be set to any suitable positions on the substrate surface 18b. In the figure, the electric circuit 20a of the first optical component 20 is shown with diagonally upper left diagonal hatching, and the electric circuit 22b of the second optical component 22 is shown with diagonally upper right diagonal hatching.

In the second embodiment, the electric circuits 20a and 22b are formed on a circuit board different from the board 18, and the first optical component 20 is an optical component consisting only of the light emitting element 20b and the second optical component 22. Alternatively, the optical component may include only the light receiving element 22a.

FIG. 8 is a perspective view schematically showing the overall construction of the third embodiment of the present invention. In the description of the third embodiment, the differences from the first embodiment are mainly described, and the detailed description of the same points as the first embodiment is omitted.

In this embodiment, the second optical component 22 is an optical circuit having an optical input section 22c and a signal processing section 22d and is composed of only optical elements. Light incident surface 22a of the first embodiment
Similarly to 1, the light incident surface of the light input portion 22c is positioned with respect to the corresponding second diffraction grating 16. The material forming the second optical component 22 is an electro-optical material or any other suitable material. In the figure, the dotted portion of the second optical component 22 indicates the light input unit 22c, and the undotted portion indicates the signal processing unit 22d.

The light input portion 22c is the corresponding second diffraction grating 1
The optical signal L from 6 is input, and this optical signal L is input to the signal processing unit 22d. The signal processing unit 22d includes the optical input unit 22
It operates based on the optical signal L incident from c. For example,
The signal processing unit 22d performs an optical logic operation and outputs the operation result to a circuit (not shown) in the next stage, or modulates the optical signal L and outputs the modulated signal to the circuit in the next stage. To do.

FIG. 9 is a perspective view schematically showing the overall construction of the fourth embodiment of the present invention. In the description of the fourth embodiment, mainly the points different from the first embodiment will be omitted, and the detailed description of the same points as the first embodiment will be omitted.

In this embodiment, the first optical component 20 is an optical circuit having an optical input / output section 20c and a signal processing section 20d, and is composed of only optical elements. Light exit surface 20b of the first embodiment
Similarly to 1, the light input / output surface of the light input / output unit 20c is positioned with respect to the first diffraction grating 14. The second optical component 22 is an optical circuit having a light input / output unit 22e and a signal processing unit 22d, and is composed of only optical elements. Similar to the light emitting surface 22a1 of the first embodiment, the light input / output surface of the light input / output unit 22e is positioned with respect to the corresponding second diffraction grating 16. The material for forming the optical components 20 and 22 is an electro-optical material or any other suitable material. In the figure, the dotted portions of the first optical component 20 and the second optical component 22 indicate the light input / output units 20c and 22e, and the undotted portions indicate the signal processing units 20d and 22d. .

The first optical component 20 and the second optical component 22 are composed of the first diffraction grating 14, the light distribution waveguide 12 and the second diffraction grating 1.
Optical signals are transmitted and received via 6. Then, the first optical component 20 operates based on the optical signal incident from the second optical component 22, and performs, for example, optical logic operation. The second optical component 22 operates based on the optical signal incident from the first optical component 20, and performs optical logic operation, for example.

That is, the signal processing section 2 of the first optical component 20.
0d generates an optical signal and outputs it to the optical input / output unit 20c. Then, the optical input / output unit 20c outputs the optical signal incident from the signal processing unit 20d to the first diffraction grating 14. Further, the light input / output unit 20c outputs the optical signal incident from the first diffraction grating 14 to the signal processing unit 20d. Then, the signal processing unit 20d operates based on the optical signal incident from the optical input / output unit 20c.

Similarly, the signal processing section 22 of the second optical component 22.
d generates an optical signal and outputs it to the optical input / output unit 22e. Then, the optical input / output unit 22e outputs the optical signal incident from the signal processing unit 22d to the second diffraction grating 16. The optical input / output unit 2
2e outputs the optical signal incident from the second diffraction grating 16 to the signal processing unit 22d. Then, the signal processing unit 22d operates based on the optical signal incident from the optical input / output unit 22e.

FIGS. 10 and 11 are perspective views schematically showing the construction of the essential parts of the fifth embodiment of the present invention. In this embodiment, the first diffraction grating 14 and the second diffraction grating 16 and the first optical component 20 and the second optical component 22 are provided on separate substrates. The configuration on the substrate side provided with the second diffraction grating 16 (configuration on the diffraction grating side) is
Further, FIG. 11 shows a configuration on the side of the substrate (optical component side) on which the first optical component 20 and the second optical component 22 are provided. In the description of the fifth embodiment, differences from the first embodiment will be mainly described, and detailed description of the same points as the first embodiment will be omitted.

The optical device 10 of this embodiment comprises a device portion 10a on the diffraction grating side and a device portion 10b on the optical component side. As shown in FIG. 10, the device portion 10a on the diffraction grating side includes a light distribution waveguide 12 provided on a substrate 18, a first diffraction grating 14 and a second diffraction grating 16 provided on the light distribution waveguide 12. Consists of. The device portion 10b on the optical component side is shown in FIG.
1, the substrate 18 provided with the optical distribution waveguide 12
It is composed of a first optical component 20 and a second optical component 22 provided on a substrate 26 different from the above. Here, another substrate 26 is a GaAs substrate, and the first optical component 20 and the second optical component 22 are monolithically integrated and provided on this substrate 26.

The substrate 18 and the substrate 26 are arranged so that the light emitting surface of the first optical component 20 and the light incident surface of the second optical component 22 face the corresponding first diffraction grating 14 and second diffraction grating 16, respectively. Position. These substrates 18 and 26 are
They may be fixed to each other in the positioned state, or may be separately positioned without being fixed to each other.

FIG. 12 is a perspective view schematically showing the overall construction of the sixth embodiment of the present invention. In the description of the sixth embodiment,
The differences from the first embodiment will be mainly described, and the detailed description of the same points as the first embodiment will be omitted.

The optical device 10 of this embodiment comprises a light distribution waveguide 12 provided on a substrate 18, and a first diffraction grating 14 and a second diffraction grating 16 provided on the light distribution waveguide 12, and The component 20 and the second optical component 22 are not provided.

The optical device 10 of the sixth embodiment is different from the optical device 10 of the fifth embodiment in that the number of the second diffraction gratings 16 provided is, for example, six. This is similar to the device portion 10a on the side of the diffraction grating.

By using the optical device 10 of the sixth embodiment in combination with the device portion 10b on the optical component side of the fifth embodiment, it is possible to change the number of second optical components 22 to which an optical signal is incident. .

The present invention is not limited to the above-mentioned embodiment, and therefore, the shape of each component, the arrangement position,
The number of arranged elements, the forming material, the constitution and others can be arbitrarily changed within the scope of the gist of the present invention.

For example, GaAs is used as the substrates 18 and 26.
A Si substrate may be used instead of the substrate. In this case, it is preferable to use, as the optical signal wavelength λ, a wavelength transparent to the Si substrate, for example, a wavelength of 1.3 μm or more. For example, if a surface emitting laser element having InGaAsP as an active layer is used as the light emitting element 20b, the oscillation wavelength of the light emitting element 20b, that is, the optical signal wavelength λ can be made transparent to the Si substrate.

In the above-mentioned embodiment, the light distribution waveguide 12
Although a multi-layered waveguide made of a compound semiconductor is used as the waveguide, a single-layered waveguide made of an amorphous material such as a quartz glass film may be used.

The first optical component 20 may be provided on the light distribution waveguide 12 on the side opposite to the substrate 18. The second optical component 22 may be provided on the light distribution waveguide 12 on the side opposite to the substrate 18.

[0070]

As is apparent from the above description, according to the optical device of the present invention, even if the distance between the first diffraction grating and the optical component corresponding to the diffraction grating is shortened, the second diffraction grating is used. An optical signal can be distributed to each optical component corresponding to the grating. Therefore, space can be saved.

In the optical device of the present invention, for example, the optical signal from the optical component corresponding to the first diffraction grating is used as a common optical signal,
This common optical signal is suitable for use in the case of simultaneously entering the optical components corresponding to the respective second diffraction gratings. Further, the optical device of the present invention is suitable for use, for example, in the case of exchanging an optical signal between the optical component corresponding to the first diffraction grating and the optical component corresponding to each second diffraction grating.

[Brief description of drawings]

FIG. 1 is a perspective view schematically showing the overall configuration of a first embodiment of the present invention.

FIG. 2 is a cross-sectional view schematically showing an enlarged main part configuration of a first embodiment of the present invention.

FIG. 3 is a diagram for explaining optical signal distribution.

FIG. 4 is a diagram for explaining a modified example of the first diffraction grating.

FIG. 5 is a diagram for explaining a modified example of the first diffraction grating.

FIG. 6 is a diagram for explaining a modified example of the second diffraction grating.

FIG. 7 is a perspective view schematically showing the overall configuration of a second embodiment of the present invention.

FIG. 8 is a perspective view schematically showing an overall configuration of a third embodiment of the present invention.

FIG. 9 is a perspective view schematically showing an overall configuration of a fourth embodiment of the present invention.

FIG. 10 is a perspective view schematically showing a main part configuration of a fifth embodiment of the present invention.

FIG. 11 is a perspective view schematically showing a main part configuration of a fifth embodiment of the present invention.

FIG. 12 is a perspective view schematically showing an overall configuration of a sixth embodiment of the present invention.

[Explanation of symbols]

10: Optical device 12: Optical distribution waveguide 14: First diffraction grating 16: Second diffraction grating 18: Semi-insulating GaAs substrate 20: First optical component 22: Second optical component

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A 64-24210 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H01L 27/15 G02B 6/12

Claims (5)

(57) [Claims] 1. A planar light distribution waveguide, and an optical signal which is provided in the light distribution waveguide and is incident from a first direction intersecting the light guiding direction of the light distribution waveguide, A first diffraction grating for diffracting in the optical waveguide direction of the waveguide and coupling with the optical distribution waveguide; and an optical signal provided in the optical distribution waveguide and guided through the optical distribution waveguide, the optical distribution A second diffraction grating for diffracting in a second direction intersecting the optical waveguide direction of the waveguide and emitting the light from the light distribution waveguide, wherein the first diffraction grating is radial when viewed from the first direction. An optical device comprising: a diffraction grating for diffracting an optical signal, wherein a plurality of second diffraction gratings are discretely arranged in a waveguide region of the radially diffracted optical signal. 2. A light device according to claim 1, a first optical component for emitting the optical signal to the first diffraction grating, before
Note that the optical signals are respectively input from the multiple second diffraction gratings.
Are arranged at positions corresponding to the respective second diffraction gratings.
An optical device comprising: a second optical component . 3. The optical device according to claim 2, wherein the light distribution waveguide is provided on one substrate surface of the substrate so as to extend in a plane shape along the substrate surface, and the first optical component and the plurality of first optical components are provided. An optical device comprising two optical components provided on the other substrate surface of the substrate. 4. The optical device according to claim 2, wherein the light distribution waveguide is provided on one substrate surface of the substrate so as to extend in a plane shape along the substrate surface, and the first optical component and the plurality of first optical components are provided. An optical device comprising: two optical components provided on a substrate different from the substrate provided with the light distribution waveguide. 5. The optical device according to claim 3 or 4, wherein the first diffraction grating and the second diffraction grating are second-order diffraction gratings for the optical signal wavelength, and the first direction and the second direction are: An optical device characterized by being formed in a direction normal to a substrate surface of a substrate provided with a light distribution waveguide.