JPS60191210A - Optical waveguide device - Google Patents

Abstract

PURPOSE:To obtain a small-sized and functional optical waveguide device by connecting an optical waveguide body, a curved surface prism, and optical transmission mediums into one body and arranging an optical film having an optical branching or demultiplexing function or the like in a required position and arranging the transmission mediums for input/output with optical axes parallel with one another. CONSTITUTION:An optical waveguide body 31, an optical branching film 32, and curved surface prisms 33-35 are connected into a one-body structure and are fixed on a bottom plate 37 of an attaching structure body, and input/output optical fibers 11-13 are adhered to input/output planes of curved surface prisms 33-35 through a supporting block 38 so that their optical axes are parallel with one another, thus constituting an optical branching and coupling device 30. The incident light from the optical fiber 11 for input is totally reflected on the curved surface prism 33 to become a parallel beam P and is transmitted through the body 31 and is branched to a transmitted light P1 and a reflected light P2 by the branching film 32. These lights P1 and P2 are totally reflected on curved surface prisms 34 and 35 respectively and are condensed and are inputted to optical fibers 12 and 13 for output and are transmitted. Thus, the small- sized and functional optical waveguide device is obtained.

Description

Detailed Description of the Invention (a) Technical Field of the Invention The present invention relates to an optical waveguide device used in an optical transmission circuit, and particularly relates to a coupling structure between an optical waveguide body and an optical transmission medium, which are the constituent elements thereof. be. Note that in this specification, an optical waveguide device refers to a device for branching/coupling light, demultiplexing/demultiplexing, etc.
Refers to an optical device that performs multiplexing or similar functions. Furthermore, the term "optical film" refers to an optical film that transmits part of the light and reflects the other part, thereby having functions such as branching or demultiplexing the light.

(b) Background of the Technology Various optical devices are used in optical transmission circuits, and optical waveguide devices such as those described above are often used. Although this type of optical waveguide device is mounted in an optical transmission circuit together with other optical devices, its mounting area is small and it is therefore desirable to have a structure that can be miniaturized. It is rare.

(c) Prior art and problems Figures 1 and 2 are diagrams for explaining a conventional example,
FIG. 1 is a diagram showing the basic configuration of a conventional optical branching device as an example of an optical waveguide device, and FIG. 2 is a diagram showing the basic configuration of a conventional optical demultiplexer/multiplexer as another example. In these figures, the same or equivalent parts are indicated by the same reference numerals.

In the conventional example shown in FIG. 1, reference numerals 11, 12.degree. 13 indicate optical fibers (optical transmission media), 16.17.degree. 18 indicate lenses, and 21 indicates a half mirror (branching film), respectively. Each of these parts (components) is arranged individually with a space between them, and is fixed at a predetermined position by a fixing structure (not shown) K such as a housing.

The signal light P emitted from the optical fiber 11 for human power is converted into a parallel beam by the lens 16, and the half mirror 2
1 and transmitted light Pl by this half mirror 21.
and reflected light P2.

The transmitted light tl is condensed by a lens 17, and then input to an output optical fiber 12 and transmitted.

On the other hand, the reflected light P2 is focused by the lens 18, and then input to the output optical fiber 13 and transmitted. However, this optical splitter requires the optical axis of the output optical fiber/<13 that transmits the reflected light (branched light) P2 to be arranged at right angles to the optical axis of the input optical fiber 11, which makes it difficult to use. There is a problem of being formalized. Also, even if no-
Even if the arrangement angle (inclination angle) of the mirror 21 is changed, the optical fiber 13 needs to be arranged diagonally with respect to the optical fiber 11, so the problem of increasing the size cannot be solved. Furthermore, optical fibers 11 to 13 and a lens 16
18 and the no-mirror 21 are arranged separately with a space between them, which also causes an increase in size.

In the conventional example shown in FIG. 2, reference numerals 11 to 15 indicate optical fibers, 16 to 20 indicate lenses, and 22 to 24 indicate interference film filters (branching films), respectively.

Similar to the conventional example shown in FIG. 1 above, these parts (components) are arranged individually with space between them, and are fixed at predetermined positions by a fixing structure (not shown) such as a housing. Ru. The signal light P emitted from the input optical fiber 11 has a plurality of different wavelengths λl.

λ2. λ3. The signal light includes λ4, is converted into a parallel beam by the lens 16, and enters the filter 22. The filter 22 transmits only the signal light Pi having the wavelength λ1, and transmits the other signal light P2(λ2)I''3(λ3).

P4 (λ4) is reflected. The transmitted signal light Pt(λ
1) is condensed by a lens 17, then input to an output optical fiber 12 and transmitted. On the other hand, the reflected signal light P2. Ps and P4 are input to the filter 23. The filter 23 transmits only the signal light P2 having the wavelength λ2, and reflects the other signal light Ps(λ3)lP4(λ4). The transmitted signal light Pz (λ2) is collected by a lens 18 and then manually transmitted to an output optical fiber 13. On the other hand, the reflected signal light Ps(2g,)
+P4 (λ4) is input to the filter 24. The filter 24 transmits only the signal light P3 having the wavelength λ3, and reflects the other signal light P4 (λ4). Transmitted signal light Pg
(λ3) is focused by the lens 19 and then input to the output optical fiber 14 and transmitted. On the other hand, the reflected signal light P4 (λ4) is focused by the lens 20, and then input to the output optical fiber 15 and transmitted.

In this way, the signal light P (λl, λ2.λ3.λ4) emitted from the output optical fiber 11 is demultiplexed into each wavelength and transmitted. That is, in the case shown in FIG. 2, it functions as a duplexer. In addition, in FIG. 2, if the direction in which each signal light emerges is reversed from the direction shown, it will function as a multiplexer. However, in the case of this optical demultiplexer/multiplexer, the optical axis of the input optical 7-eyeper 11 and the optical fibers 12 to 1 for output are connected as in the conventional example (Fig. 1).
Since it is necessary to arrange the optical axes of No. 5 in diagonal directions alternately, there is a problem in that the size is increased. Moreover, the optical fiber 11~
15, lenses 16 to 20, and filters 22 to 24 are individually arranged with space between them, which causes a problem of increased size. Further, these conventional examples have the problem that, for example, when forming a composite circuit that combines optical branching and demultiplexing functions, it is structurally very difficult to construct, and it is difficult to produce functional effects by combining them.

B) Purpose of the Invention In view of the above-mentioned problems of the prior art, an object of the present invention is to provide an optical waveguide device in which the input and output optical axes of the optical waveguide device are arranged parallel to each other, and each component is integrated. The object of the present invention is to provide an optical waveguide device that has an integrated structure, can be miniaturized, and is functional.

(e) Structure of the invention In order to achieve the above object, according to the present invention,
An optical film having a function of forming an optical waveguide body having substantially parallel opposing planes from a light-transmitting material and transmitting a part of incident light to a predetermined part of the opposing plane while simultaneously reflecting the other part. , and a plurality of curved prisms each having an outgoing light plane and a reflecting quadratic curved surface with a face angle of approximately 90°, one of which outgoing light planes is located at the light input/output portion of the opposing plane of the optical waveguide body, respectively. Arranged in a fixed form and optical transmission medium? The curved prism is connected and fixed to the other of the light output planes, and the optical axes of the optical transmission medium are arranged so that they are substantially parallel to each other and substantially parallel to the opposing plane of the optical waveguide body. An optical waveguide device is provided.

(F) Embodiments of the Invention Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

3 to 7 are diagrams for explaining the present invention in detail. In these figures, the same parts as in the above-mentioned Figs. 1 and 2 are designated by the same reference numerals.

FIG. 3 is a perspective view of an optical branch/coupler 30 which is a first embodiment of the optical waveguide device of the present invention (however, it is shown mounted on the bottom plate 37 of the mounting structure), and FIG. A plan view of the optical splitter/combiner 30 seen from the direction of arrow A in the figure, FIG. 5 is a side view of the curved prism 33 (34, 35) of FIG. Viewed curved prism 3
It is a front view of No. 3. In these figures, reference numeral 31 is an optical waveguide body, 32 is an optical branching film, 33, 34, 35 are curved prisms, 37 is a bottom plate of a mounting structure (not shown), 38
indicate optical fiber support blocks, respectively. The optical waveguide body 31 is formed from optical glass (for example, BK-7) in the shape of a rectangular parallelepiped, and in particular, side planes 31a and 31b are formed as optical surfaces parallel to each other and opposing planes. The light branching film 32 is made of a dielectric multilayer film (for example, formed by alternately depositing TiO2 and 5i02), and is formed on the side plane 31b of the main body 31.
It has the function of transmitting part of the incident light and reflecting the other part. Curved prism 33°34.35
are both formed in the same shape and have the same refractive index as that of the main body 31. As shown in Figure 5 and Part 6,
The curved prism 33 (shown as a representative) has a light plane 33a with a surface angle of 90°.

33b, and a convex reflective quadratic curved surface (for example, a paraboloid).

(hyperboloid, etc.) 33c. and,
In the curved prism 33, the optical fiber 11 is optically bonded perpendicularly to the outgoing light plane 33a, and the outgoing light plane 33b is optically bonded to a predetermined input/output portion of the side plane 31a of the main body 31. Similarly, the curved prisms 34.35 are also optically bonded to the optical fibers 12.13 and to predetermined input/output portions of the side planes 31a, 31b of the main body 31, respectively. However, the curved prism 34 is bonded onto the branch membrane 32 (see FIG. 4). As shown in FIG. 3, the main body 31 is fixed on a bottom plate 37, and the optical components 11, 12, and 13 are supported and fixed by support blocks 38 fixed on the bottom plate 37, respectively. Now, as shown in FIGS. 5 and 6, the reflection 2 of the curved prism 33
The inner surface of the boundary surface of the next curved surface 33c plays the role of a concave mirror, and converts the light beam P incident from the optical fiber 11 at an arbitrary divergence angle υ into a parallel beam by total internal reflection and outputs it. Or, conversely, it has a characteristic of condensing an incident parallel beam by total reflection and inputting it into the optical fiber 11. That is, this reflective quadratic curved surface 33c
is formed so that the angle of incidence of the incident light at each point is greater than or equal to the critical angle. Therefore, the curved prisms 33.34.
Reference numeral 35 is formed to have both the functions of a reflecting mirror and a condensing lens.

Next, the optical branching operation of the optical branching/coupling device 30 will be explained with reference to FIG. The signal light P that is emitted from the input optical fiber 11 at an arbitrary divergence angle and enters the curved prism 33 is totally reflected by the curved prism 33 and simultaneously converted into a parallel beam P, which passes through the main body 31. The light is incident on the branching film 32. Then, this parallel beam signal light P
is branched by the branching film 32 into transmitted light Pl and reflected light P2.

The transmitted light P1 is totally reflected and condensed by the curved prism 34, and then input to the output optical fiber 12 and transmitted. On the other hand, the reflected light P2 passes through the main body 31, enters the curved prism 35, is totally reflected by the curved prism 35, and at the same time is condensed, and then input to the output optical fiber 13 and transmitted. Based on this,
Signal light P input from optical fiber 11 is branched into signal lights Pl and P2, and transmitted through optical fibers 12 and 13, respectively. Note that this optical branching/coupling device 30 can be constructed by setting the direction of the input/output signal light P*PltP2 in the opposite direction to that shown in FIG. , the signal light P in which the signal lights P1 and P2 are combined is output from the optical fiber 11 and acts as an optical coupler.Furthermore, this optical branching/coupling device 30 converts the branching film 32 into a splitting film. By replacing it, it can be easily transformed into an optical demultiplexer/combiner.

As mentioned above, this optical branching/coupling device 30 includes an optical waveguide main body 3
1, branch membrane 32, curved prism 33°34.35. and input/output optical fibers 11, 12, 13 are formed into an integrated structure, and the input/output optical fiber 11
．． The optical axes of 12 and 13 are parallel to each other, and the side plane 31a of the main body 31.

31b are also formed in a parallel state, and therefore it is possible to significantly reduce the size.

FIG. 7 is a plan view of an optical demultiplexer/combiner 40 which is a second embodiment of the optical waveguide device of the present invention. In this figure, the same or equivalent parts as in FIG. 1.2 (conventional example) and FIGS. 3 to 6 (first embodiment) are indicated by the same symbols. In this case, the optical waveguide main body 41 has two coupling optical waveguides 42 and 43 connected to the first wavelength division film 44 and the second division ratio film 4.
5. The coupling optical waveguides 42 and 43 are both made of optical glass (for example, BK-7
), and the respective side planes 42a and 42b1 and 43a and 43b are formed as optical surfaces parallel to each other and facing each other. And the coupling optical waveguide 4
2 and 43 are optically bonded to each other via a first splitting film 44 and a second splitting film 45 formed at required locations on the side planes 42b and 43a. A first wavelength division film 44 and a second division ratio film 45 are also formed at required locations on the side planes 42a and 43b, respectively. The first and second splitting films (interference film filters) 44 and 45 are both formed from a dielectric multilayer film (for example, formed by alternately depositing TiO2 and 8402), which will be described later. As shown, the demultiplexing functions of each are different. The curved prisms 33, 34, 35° 36 are formed in the same manner as in the first embodiment, and the optical waveguide body 41 is formed in the same manner.
side plane 42a.

They are each optically bonded to a predetermined human output portion of 43b. And optical fiber 11, 12° 13.14
are optically bonded to the curved prisms 33, 34, 35, and 36 in the same manner, and are arranged so that their optical axes are parallel to each other and parallel to the side planes 42g and 43b of the main body 41.

However, the curved prism 36 is optically bonded onto the side plane 43b via the second splitting film 45, and the mounting form is different from the other curved prisms (33, 34, 35) (i.e., A light surface corresponding to the light surface 33a in FIG. 5 mentioned above is fixed, and an optical fiber 14 is fixed to the light surface 33b. Furthermore, a reflective film (concave reflective mirror) is provided on the reflective quadratic curved surface of the curved prism 36.
46 is formed. This reflective film 46 is provided to completely reflect the incident light without transmitting the portion where the angle is locally below the critical angle. 'Therefore, the reflective quadratic curved surface portion of this curved prism 36 is connected to other curved prisms 33,
It is also possible to omit the reflective film 46 by changing the shape of the reflection quadratic curved surface portion of 34 and 35 so as to cause total reflection.

Now, this optical demultiplexer/combiner 40 is constructed as described above, and its demultiplexing action is performed as described below. The input optical fiber 11 has wavelengths λ1. λ2
Signal light P containing light of 23 and 23 is transmitted. Then, this signal light P is transmitted from the optical fiber 11 to an arbitrary spread of 9
The light is emitted at the corner and is incident on the curved prism 33. Signal light P
is totally reflected by the curved prism 33 and simultaneously converted into a parallel beam P, transmitted through the coupling optical waveguide 42 and incident on the first splitting film 44 . This first splitting film 44 reflects only the signal light p of wavelength λ1 out of the signal light P.
Another signal light P2 having a wavelength λ2 and a signal light P3 having a wavelength λ3 are transmitted. 1. Reflected signal light P1 (λl
) is repeatedly reflected between the pair of first splitting films 44 and is incident on the curved prism 34, where it is totally reflected by the curved prism 34, simultaneously condensed, and then input into the output optical fiber 12. transmitted. On the other hand, transmitted light P2 (
λ2) IP! (λ3) passes through the coupling optical waveguide 43 and enters the second splitting film 45. This second splitting film 45
reflects only the signal light P2 of the wavelength λ2 out of the signal light P2 e Pl, and transmits the other signal light P3 of the wavelength λ3. Then, the reflected signal light P2 (λ2) is transmitted to a pair of second
The light is repeatedly reflected between the wavelength splitting films 45 and is incident on the curved prism 35, where it is totally reflected and condensed, and then manually transmitted to the output optical fiber 13. On the other hand, the transmitted light P3 (λ3) is incident on the curved prism 36, is totally reflected by the curved prism 36, is condensed, and is then input to the output optical fiber 14 and transmitted. In this way, the signal light P(λl, λ2.λ3
) is the signal light PI(λt)tP2(λ2).

Ps (λ3) is split (separated) into optical fiber 12゜1
3.14 respectively. Note that this optical demultiplexer/combiner 40 has an input/output signal light P* Pl + P2 +
If the direction of P3 is set opposite to that shown in Fig. 7,
Acts as an optical multiplexer. In addition, this optical demultiplexer/combiner 4
0, by forming the optical waveguide body 41 into a multi-layer composite body in the same manner as described above, for example, a composite body in which the coupling optical waveguides (42, 43) are integrated in a three-layer or four-layer configuration. , the number of demultiplexers (or the number of multiplexers) 1 - can be further increased.

It should be noted that the present invention is not limited to the above-mentioned embodiments. For example, by appropriately arranging branching films and branching films in a mixed manner, it is possible to easily create a composite circuit having both branching and branching functions. It is also applicable to other variations of the ridges.

(G) Effects of the Invention As explained in detail above, the optical waveguide device of the present invention skillfully connects the optical waveguide body, the curved prism as an input/output interface, and the optical transmission medium (in raw form, an optical fiber). It has an integrated structure that is combined with the
By providing an optical film with functions such as demultiplexing, and arranging the optical axes of the optical transmission media for input and output in parallel with each other,
It has the great effect of being able to be significantly miniaturized, and the formation of complex circuits, etc. is structurally easy and functional, which contributes to reducing the number of assembly steps and improving reliability of optical devices. It is something.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing the basic configuration of a conventional optical branching device as an example of an optical waveguide device, Fig. 2 is a diagram showing the basic configuration of a conventional optical demultiplexer/multiplexer as another example, and Fig. 3 is a diagram showing the basic configuration of a conventional optical splitter/multiplexer as an example of an optical waveguide device. A perspective view of an optical branch/coupler 30 that is a first embodiment of the optical waveguide device of the present invention (however, it is shown mounted on a bottom plate 37 of a mounting structure), and FIG. 4 is an arrow A in FIG. 3. 5 is a side view of the curved prism 33 (34, 35) in FIG. 4, and FIG. 6 is a front view as seen from the direction of arrow B in FIG. 5. FIG. 7 is a plan view of an optical demultiplexer/combiner 40 which is a second embodiment of the optical waveguide device of the present invention. 30... Optical branching/combining device which is the first embodiment of the guiding waveguide device of the present invention, 40... Optical branching/combining device which is the second embodiment of the optical waveguide device of the present invention, 11. 12,1
3.14...Optical fiber (optical transmission medium), 31.41
--- Optical waveguide body, 31a, 31b, 42a. 42b, 43a, 43b---side plane (optical surface), 32
-...Light branching film, 33.34, 35.36...Curved prism, 33a, 33b...Popular light surface, 33c...
・Reflection quadratic curved surface, 42.43... Optical waveguide for coupling, 4
4...First wavelength splitting film, 45...Second wavelength splitting film, 46
...reflective film side reflection mirror). Patent applicant Fujitsu Ltd. Patent application representative Patent attorney Akira Aoki Patent attorney Kazuyuki Nishidate 1) Yukio Patent attorney Akiyuki Yamaguchi Figure 1

Claims (1)

[Scope of Claims] 1. An optical waveguide body having substantially parallel opposing planes is formed from a light-transmitting material, and a part of the incident light is transmitted to a predetermined part of the opposing plane, while another part is transmitted. A plurality of curved prisms are provided with an optical film having a function of reflecting light, and have a plurality of curved prisms each having an outgoing light plane and a reflection quadratic curved surface with a face angle of approximately 90°, one of the outgoing light planes facing the optical waveguide body. They are arranged in a fixed form at the optical input and output parts on a plane,
An optical transmission medium is connected and fixed to the other Ota optical plane of the curved prism, and arranged so that the optical axes of the optical transmission medium are approximately parallel to each other and approximately parallel to the opposing plane of the optical waveguide body. Optical waveguide device with % characteristics. 2. The optical waveguide body is formed by integrating a plurality of coupling optical waveguides formed in the shape of a rectangular parallelepiped and having substantially parallel opposing planes with their opposing planes in contact with each other. An optical waveguide device according to claim 1.