JP2006285280A - Optical multiplexer/demultiplexer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multichannel type small-sized, inexpensive optical multiplexer/demultiplexer demultiplexing multiplexed optical signals in a plurality of wavelength regions into respective wavelength regions, or multiplexing lights in respective wavelength regions. <P>SOLUTION: A light produced by multiplexing lights with wavelengths λ1, λ2, λ3, λ4 is output from an optical fiber 9a, has its optical axis bent by a micro-lens 12a to be formed into a parallel light, and is reflected off a mirror layer 19. The light with the wavelength λ1 transmitted through a filter 17a is coupled to an optical fiber 9c. The lights with λ2 to λ4 reflected by the filter 17a are reflected by the mirror layer 19 to enter a filter 17b, and the light with λ2 transmitted through it is coupled to the optical fiber 9c. Through repetition of the operations, the light projected from an optical fiber 9a is demultiplexed between filters 17a to 17d and the mirror layer 19 and the lights with the respective wavelengths are projected from respective optical fibers 9c to 9f. Lights with wavelengths λ5 to λ8 incident from optical fibers 59c to 59f, on other hand, are multiplexed between filters 63a to 63d and the mirror layer 19 and projected from the optical fiber 9a. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a multi-channel and compact optical multiplexer / demultiplexer.

  In recent years, optical communication using an optical fiber cable as a signal transmission medium has been developed until it can be used in each home, and communication using a wavelength multiplexing transmission method in which optical signals having different wavelengths are multiplexed and transmitted through a single optical fiber. The network is expanding. Accordingly, it is desirable to reduce the size of an optical multiplexer / demultiplexer that multiplexes a plurality of lights having different wavelengths or demultiplexes the wavelength-multiplexed light for each wavelength, and mass-produces the light at a low cost. ing.

  FIG. 1 is a schematic side view showing a configuration of an optical demultiplexer 1 according to a conventional example (for example, Patent Document 1). An optical demultiplexer 1 shown in FIG. 1 includes five collimators 3a, 3b, 3c, 3d, and 3e in which a ball lens 4 and optical fibers 2a, 2b, 2c, 2d, and 2e are integrated and arranged in parallel. A glass body 6 having two parallel surfaces 6a and 6c and a surface 6b orthogonal thereto, and the glass body 6 are arranged in parallel on the surface 6a of the glass body 6, and each has a band of specific wavelengths λ1, λ2, λ3, and λ4. The interference film filters 5a, 5b, 5c, and 5d that transmit only light, and the reflection mirror 7 that is in close contact with the surface 6c of the glass body 6 are configured.

  In this optical demultiplexer 1, the light beam emitted from the collimator 3a and incident on the glass body 6 (light obtained by multiplexing the wavelengths λ1, λ2, λ3, and λ4) is totally reflected by the surface 6b of the glass body 6, Further, the light is totally reflected by the surface 6c (reflection mirror 7) and enters the interference film filter 5a. Since the light having the wavelength λ1 that has passed through the interference film filter 5a enters the collimator 3b, the light having the wavelength λ1 can be extracted from the light emitting end of the optical fiber 2b. The light having the wavelengths λ2, λ3, and λ4 reflected by the interference film filter 5a is further totally reflected by the reflection mirror 7, enters the interference film filter 5b, and the light having the wavelength λ2 transmitted through the interference film filter 5b is collimator. Incident on 3c. In this way, the demultiplexing proceeds while repeating reflection by the interference film filters 5a to 5c and the reflection mirror 7, and the lights having wavelengths λ1, λ2, λ3, and λ4 transmitted through the interference film filters 5a, 5b, 5c, and 5d, respectively, It can be taken out from the light emitting ends of the optical fibers 2b, 2c, 2d and 2e.

  However, in the optical demultiplexer 1 shown in FIG. 1, since the light emitted from the collimator 3a must be incident obliquely toward the surface 6a of the glass body 6, the number of wavelengths to be demultiplexed (or the optical fiber As the number) increases, the distance from the collimator 3a to the surface 6a of the glass body becomes longer, and there is a problem that the optical demultiplexer 1 becomes larger. Further, the installation positions of the collimators 3a to 3e and the glass body 6 are determined, the plurality of interference film filters 5a to 5d are attached to the glass body 6 one by one with high accuracy, and the reflection mirror 7 is formed on the glass body 6 with high accuracy. Since the manufacturing process, such as, was complicated, production efficiency could not be improved, and it was difficult to reduce costs.

JP-A-60-184215

  The present invention has been made in view of the problems of the above-described conventional example, and the object of the present invention is to demultiplex light into a plurality of wavelengths or wavelength ranges or to combine light with a plurality of wavelengths or wavelength ranges. It is an object of the present invention to provide a multi-channel type small and inexpensive optical multiplexer / demultiplexer.

  An optical multiplexer / demultiplexer according to the present invention includes a light reflecting surface, a plurality of first wavelength selection elements having different transmission wavelengths arranged in a plane parallel to the light reflecting surface, and a surface parallel to the light reflecting surface. And a plurality of second wavelength selection elements having different transmission wavelengths arranged therein, and guides light while reflecting light between the light reflection surface and each of the first wavelength selection elements, and also has different wavelengths. And guiding light while reflecting light between the light reflecting surface and each of the second wavelength selection elements, and transmitting light of a plurality of wavelengths while demultiplexing light having different wavelengths. And a plurality of lights arranged along the arrangement direction of the first wavelength selection elements such that the optical axis is substantially perpendicular to the plane on which the first wavelength selection elements are arranged The input means and the optical axis are substantially perpendicular to the surface on which the second wavelength selection elements are arranged. A plurality of light output means arranged along the arrangement direction of the second wavelength selection elements, and one for bending the optical axis direction of the transmitted light arranged facing the light input means. Or a plurality of first deflecting elements, one or a plurality of second deflecting elements arranged to face the light output means for bending the optical axis direction of transmitted light, and the light guide means A set of light of a plurality of wavelengths combined between the light reflecting surface and the first wavelength selection element is guided to the transmission means and coupled to the transmission means, and the transmission means is transmitted to the transmission means. A light branching unit that guides light of a set of a plurality of wavelengths between the light reflection surface of the light guide unit and the second wavelength selection element, and the light input unit includes the first deflection unit. The light of the light guide means is emitted by emitting light of each wavelength out of a set of multiple wavelengths of light through the element. The light output means makes light of each wavelength out of another set of plural wavelengths of light emitted obliquely from the second wavelength selection element of the light guide means. Light is received through the second deflection element.

  Here, as the transmission means, for example, an optical fiber or an optical waveguide can be used. An optical fiber, a semiconductor laser element, etc. can be used as the light input means. As the light output means, an optical fiber, a photodiode, or the like can be used. As the wavelength selection element, a filter, a diffraction element such as a diffraction grating or a CGH element, or the like can be used. Further, the deflection element may be constituted by a lens that is not rotationally symmetric around its central axis, and is constituted by a rectilinear lens arranged so that the center in the cross section of the transmitted light beam is deviated from the optical axis. Alternatively, it may be constituted by a prism and a lens, or may be constituted by a mirror and a lens.

  In the optical multiplexer / demultiplexer according to the present invention, the light emitted from each of the light input means is bent by the first deflecting element and obliquely incident on the light guiding means, and the light guiding means by the first wavelength selecting element. The light of the plurality of wavelengths combined in the step is emitted obliquely from the light guide means, and the light of the plurality of wavelengths emitted from the light guide means is bent by the first deflecting element and coupled to the transmission means. Can be transmitted by the transmission means. Further, light of a plurality of wavelengths transmitted by the transmission means is emitted from the transmission means, this light is bent by the second deflecting element and incident obliquely on the light guide means, and the light guide means is guided by the second wavelength selection element. The light of each wavelength demultiplexed in (5) can be emitted obliquely from the light guide means, and the light of each wavelength emitted from the light guide means can be bent by the second deflection element and received by the respective light output means.

  In the optical multiplexer / demultiplexer of the present invention, since the optical input means, the optical output means, and the transmission means can be arranged in parallel, the optical axes of the optical input means, the optical output means, and the transmission means are perpendicular to the wavelength selection element. The optical multiplexer / demultiplexer can be downsized. Further, according to this optical multiplexer / demultiplexer, since an optical signal can be transmitted / received by one transmission means, construction work when two optical multiplexer / demultiplexers are connected is simplified.

  In one embodiment of the optical multiplexer / demultiplexer of the present invention, the optical branching unit includes the set of light of a plurality of wavelengths transmitted by the transmission unit and the another set of plurals transmitted by the transmission unit. A filter that multiplexes and demultiplexes light of wavelengths, and a set of light beams of a plurality of wavelengths that are multiplexed between the light reflection surface of the light guide unit and the first wavelength selection element. An optical fiber and a core for guiding the other set of light of multiple wavelengths separated by the filter to the second wavelength selection element of the light guide means, such as an optical fiber, a core, a prism, and a mirror And at least one of light transmission means such as a prism and a mirror. According to such an embodiment, after the optical signal transmitted / received through the transmission means is separated by the filter, at least one of the separated optical signals is separated using the optical transmission means such as an optical fiber, a core, a prism, and a mirror. Since it can guide to a desired location, the transmission means can be easily unified.

  In another embodiment of the optical multiplexer / demultiplexer of the present invention, the transmission means may be constituted by an optical fiber, the light input means may be constituted by a light emitting element, and the light output means may be constituted by a light receiving element. . According to such an embodiment, a transponder including a light emitting element and a light receiving element can be manufactured.

  In still another embodiment of the optical multiplexer / demultiplexer according to the present invention, the light guide means includes a light guide means on the transparent first substrate having the light reflection surface formed on the back surface, A transparent second substrate on which a plurality of wavelength selection elements are arranged is joined. According to this embodiment, since the first substrate and the second substrate are manufactured separately and bonded together with a transparent adhesive or the like, the light guide means of the optical multiplexer / demultiplexer can be easily manufactured. Become.

  In still another embodiment of the optical multiplexer / demultiplexer according to the present invention, the light guiding means is formed on a transparent first substrate having the light reflecting surface formed on the back surface, and the individual wavelength selecting elements on the respective surfaces. A plurality of transparent second substrates formed with the above are aligned and joined. As in this embodiment, the second substrate on which the wavelength selection element that transmits a specific wavelength or wavelength range is formed is arranged for each transmission wavelength, and is adhered to the first substrate with a transparent adhesive. If it joins together, the manufacturing process of the light guide means of an optical multiplexer / demultiplexer will become easy.

  In another embodiment of the optical multiplexer / demultiplexer according to the present invention, the light guiding means includes the wavelength selection elements formed between a pair of transparent substrates stacked, and the substrate located on the back side of the substrates. The light reflecting surface is formed on the back surface of the substrate. According to this embodiment, by adjusting the thicknesses of the two transparent substrates, the distance between the first optical fiber and the second optical fiber and the distance between the second optical fibers, the transmission means, Since the distance between the light emitting elements and the distance between the light emitting elements, the distance between the transmission means and the light receiving element, and the distance between the light receiving elements can be adjusted, the optical path in the light guiding means of the optical multiplexer / demultiplexer must be designed accurately. Can do.

  In still another embodiment of the optical multiplexer / demultiplexer of the present invention, the surface of the light guide unit on which the wavelength selection element is formed and the deflection element are opposed to each other, and the light guide unit and the deflection element A spacer is interposed between them. In this embodiment, since the distance between the deflecting element and the light reflecting surface can be kept constant only by interposing a spacer having a constant thickness, it is troublesome to adjust the distance between the deflecting element and the transmission means, the light input / output means, etc. This makes it easier to manufacture the optical multiplexer / demultiplexer. If the spacer is formed integrally with the deflection element, the positional accuracy in the height direction between the wavelength selection element and the deflection element can be further improved.

  In still another embodiment of the optical multiplexer / demultiplexer of the present invention, the surface of each wavelength selection element is covered with a protective layer. By covering with a protective layer, it is possible to prevent changes in characteristics of wavelength selection elements such as filters due to moisture and the like, and adhesion of scratches and dirt.

  In another embodiment of the optical multiplexer / demultiplexer of the present invention, the deflecting element is constituted by a lens that is not rotationally symmetric about the central axis. If such a deflection element is used, the optical axis direction of the light can be bent only with the lens, and the area where the lens is provided can be made to coincide with the incident light beam, and the installation area of the lens can be reduced. Can do.

  Further, in the deflecting element in still another embodiment of the optical multiplexer / demultiplexer of the present invention, a spherical lens, an aspherical lens, or an anamorphic arranged so that the center of the cross section of the transmitted light beam is deviated from the optical axis. It consists of a lens. If such a deflection element is used, light can be bent using an inexpensive lens.

  The deflection element in still another embodiment of the optical multiplexer / demultiplexer of the present invention may be constituted by a prism and a lens. According to such a deflection element, an inexpensive lens such as a spherical lens, an aspherical lens, or an anamorphic lens can be used as the lens. Here, if this prism is formed on one surface of the transparent substrate and the lens is provided on the other surface of the transparent substrate so as to face the prism, it is not necessary to position the lens and the prism. Can also be reduced. Further, this prism may be formed integrally on the surface of the light guide means, and the lens may be disposed at a position facing the prism. In this case, the number of parts can be reduced by integrating the prism with the light guide means.

  It should be noted that the above-described components of the present invention can be combined as much as possible.

(First embodiment)
FIG. 2 is a schematic exploded perspective view showing the structure of the optical multiplexer / demultiplexer 8a according to the first embodiment of the present invention. FIG. 3 is a schematic cross-sectional view of the optical fiber 9a to 9f of the optical multiplexer / demultiplexer 8a shown in FIG. 2 in a plane passing through the core 9, and illustrates the state of demultiplexing or multiplexing. FIG. 4 is a schematic side view of the optical multiplexer / demultiplexer 8a shown in FIG. First, the configuration of the optical multiplexer / demultiplexer 8a of the present invention shown in FIGS.

  The optical multiplexer / demultiplexer 8a according to the present invention includes an optical fiber array 11 having optical fibers 9a, 9b, 9c, 9d, 9e, and 9f arranged in parallel at a constant pitch without gaps and a connector 10 attached to the tip, and a plurality of optical fibers on the bottom (see FIG. 6) microlens array 14 having microlenses 12a, 12b, 12c, 12d, 12e, and 12f, and a transparent cover member 20 such as a glass plate having an AR coating layer (antireflection film) 21 formed on the surface. A filter composed of spacers 15a, 15b, 15c, 15d, a release film 13, filters 17a, 17b, 17c, 17d and dummy films 18a, 18b for keeping the distance between the microlenses 12a-12f and the AR coating layer 21 constant. It is composed of a layer 17, a light guide block 16, and a mirror layer 19. The mirror layer 19 is a layer made of a dielectric multilayer film or a metal vapor deposition film having a high reflectance.

  The microlens array 14, the AR coating layer 21, the filter layer 17, and the mirror layer 19 are arranged in parallel to each other. Further, the microlenses 12a to 12f are installed so as to be as close as possible to the AR coating layer 21. The optical fibers 9 a to 9 f in the connector 10 are arranged perpendicular to the microlens array 14.

  The optical fibers 9a to 9f of the optical fiber array 11 further include a strand in which the core 9 is coated with a plastic or glass cladding, a strand in which the cladding around the core 9 is coated with plastic, or these strands. Any wire such as a core covered with plastic may be used.

  Next, the structure and role of the microlens array 14 will be described. FIG. 5 is a bottom view of the microlens array 14. A plurality (six in the figure) of microlenses 12a to 12f having the same size as the cross section of the optical fibers 9a to 9f are formed on the lower surface of the microlens array 14 with almost no gap. When considering the demultiplexing operation or multiplexing operation of the optical multiplexer / demultiplexer 8a, all the light emitted from the end faces of the optical fibers 9a to 9f must enter the microlenses 12a to 12f. In order to satisfy this condition, the thickness of the microlens array 14 may be determined as follows.

  Inside the core 9 of the optical fibers 9a to 9f, light propagates while repeating reflection at the interface with the cladding. Thus, in order to propagate light inside the core 9 without transmitting from the core 9 to the clad, the incident angle to the interface with the clad must be an angle greater than the total reflection angle. Since the incident angle to the clad interface is limited in this way, the direction of light emission from the core end and the extent of spread are naturally determined. Therefore, when the cross section of the light having a certain divergence angle spreads to the same size as the micro lenses 12a to 12f, or until it spreads to the same size as the micro lenses 12a to 12f. If the thickness of the microlens array 14 is designed so as to be incident on ˜12f, all of the light emitted from the optical fibers 9a-9f can be incident on the microlenses 12a-12f.

  In addition, the microlenses 12a to 12f are arranged and designed so that their central axes substantially coincide with the optical axes of the optical fibers 9a to 9f, and further, designed to have a shape that satisfies the following requirements. desirable. FIG. 6 is a conceptual diagram showing an optical path in the optical multiplexer / demultiplexer 8a of the present invention, where L1 is the main plane of the microlenses 12a to 12f, L2 is the surface of the mirror layer 19 (hereinafter referred to as the mirror surface L2), L3 Is a mirror image of the lens principal plane L1 with respect to the mirror surface L2. As shown in FIG. 6, after the light emitted from the optical fiber 9a enters the lens main plane L1 (microlens 12a), the microlens 12a is emitted as parallel light whose optical axis direction is bent. It is desirable that the lens has such a shape. The degree of bending of the light in the optical axis direction, that is, the incident angle to the mirror surface L2, is desirably an optimum angle of less than 10 ° for the reason described later. Note that the optical axis direction of light after passing through the lens in this way (the direction in which the light beam passes through the center of the cross section of the light beam is called the optical axis direction of the light) is the optical axis direction of the light before entering the lens. In the following, a lens that bends with respect to the lens is referred to as an inclined lens.

  Further, the microlens 12c is efficiently coupled to the optical fiber 9c by bending the optical axis direction of the light when the light emitted from the microlens 12a is reflected by the mirror surface L2 and is incident obliquely from below. Such a shape is desirable. In this optical multiplexer / demultiplexer 8a, the microlenses 12c to 12f may be incident at the same incident angle and may be emitted at the same emission angle. Therefore, the microlenses 12c to 12f are all the same using a collimator lens. The shape may be different, or different shapes may be used so as to obtain an optimum focal length using a condensing lens. In the present embodiment, the microlens 12b is not used and may be omitted. However, for common use with the second embodiment and the like, FIGS. 2 to 5 show the microlens array 14 including the microlenses 12b. The micro lens 12b may have the same shape as the micro lens 12c.

  The microlenses 12a to 12f satisfying the above requirements are circular from the aspherical lens 25 at a position deviated from the optical axis of the aspherical lens 25, as shown in the top and front views in FIGS. It is obtained by cutting out.

  Further, the microlens array 14 having the microlenses 12a to 12f on the surface presses a stamper having the reverse pattern of the microlenses 12a to 12f on the surface against an uncured resin such as an ultraviolet curable resin. It can be easily molded by a stamper method or the like in which the resin is cured by irradiating ultraviolet rays. Further, if the inverted patterns of the spacers 15a, 15b, 15c, and 15d are also formed on the stamper, the microlenses 12a to 12f and the spacers 15a, 15b, 15c, and 15d can be formed at the same time. If the microlenses 12a to 12f and the spacers 15a to 15d can be formed at the same time, the manufacturing process can be simplified rather than bonding the spacers 15a to 15d created individually to the microlens array 14, and the microlenses 12a to The positional accuracy between 12f and the filters 17a to 17d can also be improved.

  In the optical multiplexer / demultiplexer 8a according to the present invention, as shown in FIG. 6, the light exits from the optical fiber 9a, passes through the micro lens 12a (the region below the optical fiber 9a in the main plane L1), and is reflected by the mirror surface L2. Each component is formed and arranged so that the parallel light beam is incident on the micro lens 12c (a region below the optical fiber 9c in the main plane L1). For example, when the arrangement of the microlenses 12a to 12f is determined by the arrangement of the optical fibers 9a to 9f, and the incident angle to the mirror surface L2 is determined from the shape of the microlens 12a, as shown in FIG. All the parallel light emitted from the microlens 12a is incident on the mirror image L3 of the lens main surface L1 with respect to the mirror surface L2 (the mirror image 12c ′ of the microlens 12c) and condensed, and the mirror image 9c ′ of the optical fiber 9c with respect to the mirror surface L2. The position of the mirror surface L2 may be determined so as to couple to The distance between the microlens array 14 and the mirror layer 19 can be adjusted by adjusting the thickness of the light guide block 16 and the thickness of the cover member 20.

  Further, when the arrangement of the microlenses 12a to 12f is determined by the arrangement of the optical fibers 9a to 9f and the thickness of the light guide block 16 and the cover member 20 is determined, the bending angle of the microlens 12a is appropriate. The microlens 12a may be designed to have an angle.

  The alignment of the optical fiber array 11 and the microlens array 14 is performed by applying an uncured adhesive between the optical fiber array 11 and the microlens array 14 and then in an uncured state of the optical fiber 9a. , 9b, 9c, 9d, 9e, and 9f are irradiated, and the position is adjusted while measuring the intensity of the light transmitted through each of the micro lenses 12a, 12b, 12c, 12d, 12e, and 12f, and bonding is performed at the optimum position. The agent should be cured.

  Next, the filter layer 17 will be described. FIG. 8 is a diagram showing the transmission wavelength characteristics of the filters 17a to 17d, the dummy films 18a and 18b, and the AR coating layer 21, where the horizontal axis indicates the wavelength and the vertical axis indicates the light transmittance. Filters 17a, 17b, 17c, and 17d transmit light in the wavelength ranges centered on wavelengths λ1, λ2, λ3, and λ4, respectively, and reflect light in other wavelength ranges, as indicated by solid lines in FIG. It is a dielectric multilayer film. The dummy films (spacers) 18a and 18b and the AR coating layer 21 are members using, for example, thin film glass, quartz, a transparent resin film, and the like. As shown by a broken line in FIG. Transmits light.

  Here, the manufacturing method of the filter layer 17 of the optical multiplexer / demultiplexer 8a of the present invention will be described with reference to FIGS. First, a very thin release film 13 is formed of a transparent material on the surface of a substrate 22 such as glass shown in FIG. 9A using a spin coater as shown in FIG. 9B. The material of the release film 13 may be any material such as polyimide that can be easily peeled off from the substrate 22 by applying a certain condition such as heating, contact with water, and ultraviolet irradiation after forming a transparent thin film.

  On the surface of the release film 13, a filter thin film (dielectric multilayer film) 27 having each characteristic is formed for each substrate 22, as shown in FIG. Thus, what formed the peeling film 13 and the filter thin film 27 on the board | substrate 22 is prepared for the kind of required filters 17a-17d. Further, the dummy films 18a and 18b are formed of transparent thin glass, quartz, transparent resin film or the like with the same thickness as the total thickness of the release film 13 and the filter thin film 27.

  Next, as shown in FIG. 9D, the filter thin film 27 and the peeling film 13 on the substrate 22 are cut into the widths of the filters 17a, 17b, 17c, and 17d used in the optical multiplexer / demultiplexer 8a. Here, since the filter thin film 27 and the release film 13 are preferably cut, it is not necessary to cut the substrate 22 completely. After the filter thin film 27 and the release film 13 are cut, the release film 13 is released from the substrate 22 as shown in FIG.

  Next, a transparent adhesive is applied to the surface of the parent substrate of the light guide block 16, and the filters 17a, 17b, 17c, and 17d and the dummy films 18a and 18b having the release film 13 on the back surface are shown in FIG. ) Are arranged one by one in the order shown in FIG. 2 and are bonded to the surface of the parent substrate of the light guide block 16. In this case, the filter layer 17 may be brought into close contact with the parent substrate of the light guide block 16 by pressing from above with a flat plate. Further, the filters 17a to 17d and the dummy films 18a and 18b are arranged on the flat table so that the parent substrate of the light guide block 16 coated with a transparent adhesive is pressed on the surface. The layer 17 and the light guide block 16 may be bonded. Thereafter, a mirror layer 19 is preferably formed on the back surface of the parent substrate of the light guide block 16 by sticking a sheet on which a metal thin film is formed or vapor-depositing a metal material. Further, after the mirror layer 19 is formed in advance on the back surface of the parent substrate of the light guide block 16, the filters 17a to 17d and the dummy films 18a and 18b may be bonded to the surface.

  Next, the parent substrate of the light guide block 16 in which the filter layer 17 and the mirror layer 19 are formed on the front surface and the back surface is cut at a portion indicated by a broken line in FIG. 11 and individual light guides are obtained as shown in FIG. If it cuts into the shape of the block 16, the light guide block 16 in which the filter layer 17 and the mirror layer 19 were formed can be mass-produced efficiently. Next, the cover member 20 in which the AR coating layer 21 is formed on the filter layer 17 on the surface of the light guide block 16 is joined.

  Further, the filter layer 17 on the parent substrate and the parent substrate of the cover member 20 having the AR coating layer 21 formed on the surface thereof are bonded with a transparent adhesive, and then the cutting shown in FIG. The duplexer 8a can be manufactured. If the filter layer 17 is covered with the cover member 20 before cutting in this way, the filter layer 17 is not soiled or damaged during cutting, and the yield can be reduced.

  Moreover, you may produce the filter layer 17 with the following method demonstrated using FIG. 12, FIG. First, a release film 23 is formed on the surface of the substrate 22 shown in FIG. 12A using a spin coater as shown in FIG. 12B. The release film 23 may be a substance that changes its properties by heating, contact with water, ultraviolet irradiation, or the like, such as polyimide, and is easily peeled off from the substrate 22 or the filter thin film 27.

  On the surface of the release film 23, as shown in FIG. 12C, a filter thin film 27 made of a dielectric multilayer film having each characteristic is formed for each substrate 22. Only the necessary filter types are prepared with the filter thin film 27 thus formed. A release film 13 is further formed on the surface of the filter thin film 27 as shown in FIG.

  Next, as shown in FIG. 13 (e), a dicing tape 24 is adhered to the surface of the upper release film 13, and as shown in FIG. 13 (f), the release film on the substrate 22 side by heating, ultraviolet irradiation or the like. 23 is peeled from the filter thin film 27. At this time, only the substrate 22 may be peeled while the lower peeling film 23 is adhered to the filter thin film 27. In that case, since the filter thin film 27 is covered with the peeling films 13 and 23 from both sides, the filter thin film 27 is hardly damaged and is easy to handle.

  Next, the surface of the dicing tape 24 on which the filter thin film 27 is formed is faced up and cut into the widths of the filters 17a, 17b, 17c, and 17d as shown in FIG. Thereafter, the dicing tape 24 is peeled off from the release film 13 by irradiating ultraviolet rays, the filters 17a to 17d are arranged on the light guide block 16, and the release film 13 is adhered to the light guide block 16 with a transparent adhesive. The dummy films 18 a and 18 b formed to the same thickness as the combined thickness of the release film 13 and the filter thin film 27 are also bonded to the surface of the light guide block 16 with a transparent adhesive. Thereafter, similar to the manufacturing process described above, cutting may be performed so as to form individual filter layers 17.

  Next, demultiplexing of light in the optical multiplexer / demultiplexer 8a of the present invention will be described. FIG. 14 is an enlarged cross-sectional view partially cut away from FIG. 3, and is a diagram for explaining the state of demultiplexing by the optical multiplexer / demultiplexer 8a of the present invention. When light multiplexed with wavelengths λ1, λ2, λ3, and λ4 is emitted from the optical fiber 9a, the light incident on the microlens 12a from the optical fiber 9a is bent in the optical axis direction by the microlens 12a as described above. It becomes parallel light, passes through the AR coating layer 21 and the cover member 20, and enters the portion of the filter layer 17 where the dummy film 18 a is disposed.

  The light transmitted through the dummy film 18 a is further transmitted through the light guide block 16, reflected by the surface of the mirror layer 19, transmitted through the light guide block 16 again, and reaches the filter layer 17. Since the filter 17a is disposed at this position of the filter layer 17, the light of wavelength λ1 passes through the filter 17a and enters the microlens 12c, and the optical axis direction is bent and coupled to the optical fiber 9c. . Therefore, only the light of wavelength λ1 can be extracted from the light emitting end of the optical fiber 9c.

  On the other hand, the light (wavelengths λ 2, λ 3, λ 4) reflected by the filter 17 a is reflected again by the surface of the mirror layer 19 and enters the filter layer 17. Since the filter 17b is disposed at this position of the filter layer 17, the light of wavelength λ2 transmitted through the filter 17b is incident on the microlens 12d, and the optical axis direction is bent and coupled to the optical fiber 9d. Therefore, the light of wavelength λ2 can be extracted from the light emitting end of the optical fiber 9d.

  Similarly, the light (wavelengths λ 3 and λ 4) reflected by the filter 17 b is further reflected by the surface of the mirror layer 19 and enters the filter layer 17. Since the filter 17c is disposed at this position of the filter layer 17, the light of wavelength λ3 transmitted through the filter 17c is incident on the microlens 12e, bent in the optical axis direction, and coupled to the optical fiber 9e. Accordingly, light having a wavelength λ3 can be extracted from the light emitting end of the optical fiber 9e.

  Similarly, the light (wavelength λ 4) reflected by the filter 17 c is further reflected by the surface of the mirror layer 19 and enters the filter layer 17. Since the filter 17d is disposed at this position of the filter layer 17, the light of wavelength λ4 transmitted through the filter 17d is incident on the microlens 12f, and the optical axis direction is bent and coupled to the optical fiber 9f. Therefore, the light of wavelength λ4 can be extracted from the light emitting end of the optical fiber 9f.

  Thus, the optical multiplexer / demultiplexer 8a according to the present invention can demultiplex the multiplexed light. Conversely, if the light of the wavelengths λ1 to λ4 propagating through the optical fibers 9c to 9f is multiplexed and extracted from the optical fiber 9a, it can be used as a multiplexer.

  FIG. 15 shows the multiplexing operation of the optical multiplexer / demultiplexer 8a of the present invention. It is assumed that light of wavelengths λ1, λ2, λ3, and λ4 propagates through the optical fibers 9c, 9d, 9e, and 9f and is emitted from the end faces of the optical fibers 9c, 9d, 9e, and 9f, respectively. At this time, the light of wavelength λ4 emitted from the optical fiber 9f is converted into parallel light by passing through the microlens 12f and bent along the optical axis direction, and transmitted through the cover member 20, the filter 17d, and the light guide block 16. Then, it is reflected by the mirror layer 19. The light of wavelength λ4 reflected by the mirror layer 19 enters the filter 17c and is reflected by the filter 17c.

  On the other hand, the light of wavelength λ3 emitted from the optical fiber 9e is converted into parallel light by passing through the microlens 12e, the optical axis direction is bent, and the light passes through the cover member 20 and the filter 17c. Thus, the light of wavelength λ 4 reflected by the filter 17 c and the light of wavelength λ 3 transmitted through the filter 17 c travel in the same direction in the light guide block 16 and are reflected by the mirror layer 19. The light having the wavelengths λ3 and λ4 reflected by the mirror layer 19 enters the filter 17b and is reflected by the filter 17b.

  The light of wavelength λ2 emitted from the optical fiber 9d is converted into parallel light by passing through the microlens 12d and bent in the optical axis direction, and passes through the cover member 20 and the filter 17b. Thus, the light of the wavelengths λ3 and λ4 reflected by the filter 17b and the light of the wavelength λ2 transmitted through the filter 17b travel in the same direction in the light guide block 16 and are reflected by the mirror layer 19. Light of wavelengths λ2, λ3, and λ4 reflected by the mirror layer 19 enters the filter 17a and is reflected by the filter 17a.

  The light having the wavelength λ1 emitted from the optical fiber 9c is converted into parallel light by passing through the microlens 12c, and the direction of the optical axis is bent, and passes through the cover member 20 and the filter 17a. Thus, the light of the wavelengths λ2, λ3 and λ4 reflected by the filter 17a and the light of the wavelength λ1 transmitted through the filter 17a travel in the same direction in the light guide block 16 and are reflected by the mirror layer 19. Light having wavelengths λ1, λ2, λ3, and λ4 reflected by the mirror layer 19 passes through the light guide block 16, the dummy film 18a, and the cover member 20, and enters the microlens 12a.

  The parallel lights having wavelengths λ1, λ2, λ3, and λ4 incident on the microlens 12a are converged and condensed by the microlens 12a so that the optical axis direction is parallel to the optical axis direction of the optical fiber 9a and coupled to the optical fiber 9a. And propagates in the optical fiber 9a. In this way, the optical multiplexer / demultiplexer 8a of the present invention can multiplex and multiplex the light of each wavelength.

  In the above description, the light transmitted through the filters 17b, 17c, and 17d is incident on the microlenses 12d, 12e, and 12f, respectively. For this purpose, depending on the deflection angle of the light whose optical axis direction is bent. The thickness w2 of the light guide block 16 may be adjusted so that the distance between the adjacent microlenses 12c, 12d, 12e, and 12f matches the distance d2 of the light reflected by the mirror layer 19 at the lens position.

  In this case, the distance d1 between the microlens 12a and the microlens 12c can be adjusted by the thickness w1 of the cover member 20. As described above, in the optical multiplexer / demultiplexer 8a of the present invention, the cover member 20 has a sufficient thickness, and the optical path can be accurately designed by adjusting the thickness. The container 8a can be used. In addition, when the thickness w2 of the light guide block 16 and the thickness w1 of the cover member 20 are the same, the distance d1 between the microlens 12a and the microlens 12c is twice the reflection distance d2 at the mirror layer 19. If the microlens array 14 is designed, the optical fibers 9a, 9b, 9c, 9d, 9e, and 9f of the optical fiber array 11 are equally spaced, and the light guide block 16 and the cover member 20 are made of the same material. The cost for material procurement and processing can be reduced.

  As described above, the microlens 12a may be designed so that the incident angle of the light transmitted through the microlens 12a to the mirror layer 19 is an appropriate angle of 10 ° or less. The reason is as follows. . The incident angle of the mirror layer 19 is the incident angle to the filter layer 17 as it is, but if this angle is too large, the difference in transmittance (wavelength-dependent loss) due to the incident angles of P-polarized light and S-polarized light becomes large. Therefore, the properties of the light having the wavelength λ1 transmitted through the filter 17a and the light having the wavelength λ1 before transmission are changed. In other words, the reproducibility of light is poor. Therefore, the angle of incidence on the mirror layer 19 should not be too large, but conversely if the angle of incidence on the mirror layer 19 is too small, the thickness of the light guide block 16 and the cover member 20 is increased to increase the optical path length. Otherwise, light cannot enter the microlens 12c, the optical multiplexer / demultiplexer 8a becomes larger, and the attenuation of light increases. From the calculation and experimental results taking these into consideration, it is desirable that the incident angle to the mirror layer 19 is an optimum angle of 10 ° or less.

  The optical multiplexer / demultiplexer 8a of the present invention may be used by being housed in a casing 32 and sealed at the entrance with an adhesive 33 as shown in the schematic cross-sectional view of FIG.

  The optical multiplexer / demultiplexer 8a of the present invention includes a microlens array 14, and can bend the optical axis direction of light by the microlenses 12a to 12f. Accordingly, the light emitting end face of the optical fiber array 11 in which the optical fiber 9a that propagates the multiplexed light and the optical fibers 9c to 9f that propagate the light of each wavelength after demultiplexing are arranged in parallel, the filter layer 17 and the mirror layer. 19 can be arranged in parallel to each other, and even if the number of demultiplexing is increased, a small optical multiplexer / demultiplexer 8a can be obtained.

  The optical multiplexer / demultiplexer 8a of the present invention is designed so that the demultiplexed light is accurately incident on the microlenses 12c to 12f by adjusting the thicknesses of the cover member 20 and the light guide block 16. be able to.

(Second Embodiment)
FIG. 17 is a partially cutaway schematic cross-sectional view of the optical multiplexer / demultiplexer 8b according to the second embodiment of the present invention, and corresponds to FIG. 14 described in the first embodiment. The filters 17a, 17b, 17c, 17d, and 17e are dielectric multilayer films that transmit light of wavelengths λ1, λ2, λ3, λ4, and λ5, respectively. The filter layer 17 includes filters 17a to 17e, a release film 13, and dummy films (spacers) 18a and 18b. The filter layer 17 can be manufactured by the manufacturing process described in the first embodiment. In the optical multiplexer / demultiplexer 8b shown in FIG. 17, the description of the same components as those described in the first embodiment is omitted.

  In the optical multiplexer / demultiplexer 8b of the present embodiment, the surface of the filter layer 17 is covered with a transparent and very thin film 20a such as glass to protect the filters 17a to 17e from moisture and the like. An AR coat layer 21 is formed on the surface of the film 20a.

  Each of the filters 17a to 17e must be disposed on the optical path when the light reflected by the mirror layer 19 enters the corresponding microlenses 12b to 12f. Therefore, as shown in the first embodiment If the thickness of the cover member 20 on the layer 17 is large, it is necessary to design the arrangement of the filters 17a to 17e from the thickness of the light guide block 16 and the incident angle of light to the mirror layer 19.

  However, if the filter layer 17 is covered with a very thin film 20a as in the present embodiment, the filters 17a to 17e and the microlenses 12b to 12e are brought closer to each other than the optical multiplexer / demultiplexer 8a of the first embodiment. be able to. Therefore, the dummy film 18a is formed at a position facing the microlens 12a, and the filters 17a, 17b, 17c, 17d, and 17e are formed at positions facing the microlenses 12b, 12c, 12d, 12e, and 12f. Even if the filters 17a to 17e are arranged at the same positions as the microlenses 12b to 12f, the light reflected by the mirror layer 19 can be made incident on the filters 17a to 17e. Thus, in the present embodiment, the layout design of the filter layer 17 is not complicated like the optical multiplexer / demultiplexer 8a shown in the first embodiment.

  Further, as shown in FIG. 18, the surfaces of the filters 17 a to 17 e may not necessarily be covered with the film 20 a or the AR coating layer 21. However, the total thickness of the film 20a and the AR coating layer 21 must be the same as the total thickness of the release film 13 and the filters 17a to 17e so that the surface of the filter layer 17 becomes flat.

(Third embodiment)
FIG. 19 is a partially cutaway schematic cross-sectional view of the optical multiplexer / demultiplexer 8c according to the third embodiment of the present invention, and corresponds to FIG. 14 described in the first embodiment. In the optical multiplexer / demultiplexer 8c shown in FIG. 19, the description of the same components as those described in the first embodiment is omitted. The filter layer 17 includes filters 17a to 17e, a release film 13, and a dummy film 18a. The filter layer 17 can be manufactured by the manufacturing method described in the first embodiment. The filters 17a, 17b, 17c, 17d, and 17e are dielectric multilayer films that transmit light of wavelengths λ1, λ2, λ3, λ4, and λ5, respectively. In order to adjust the height of the microlens array 14, spacer blocks 31 a and 31 b are sandwiched between the light guide block 16 and the microlens array 14.

  In the optical multiplexer / demultiplexer 8c of this embodiment, a transparent adhesive is applied to a transparent plate 28 such as a glass plate, and the filter layer 17 is formed thereon. On the filter layer 17, a film 20a having an AR coating layer 21 on the surface is further adhered with a transparent adhesive. If the transparent plate 28 with the filter layer 17 and the like formed on the surface and the spacer blocks 31a and 31b are bonded to the surface of the light guide block 16, and the microlens array 14 and the like are further bonded, the optical multiplexer / demultiplexer 8c is completed.

(Fourth embodiment)
FIG. 20 is a partially cutaway schematic cross-sectional view of an optical multiplexer / demultiplexer 8d according to the fourth embodiment of the present invention, and corresponds to FIG. 14 described in the first embodiment. In this optical multiplexer / demultiplexer 8d, the description of the same components as those described in the first embodiment is omitted. The filter layer 17 of the optical multiplexer / demultiplexer 8d of the present embodiment includes filter blocks 29a, 29b, and 29c in which the filters 17a, 17b, 17c, 17d, and 17e or the AR coating layer 21 are formed on the surface of a transparent block such as glass. , 29d, 29e, 29f, and 29g. The filters 17a, 17b, 17c, 17d, and 17e are dielectric multilayer films that transmit light in the wavelength ranges of λ1, λ2, λ3, λ4, and λ5, respectively, and reflect light in other wavelength ranges.

  Next, the manufacturing method of the filter layer 17 of this embodiment is demonstrated using FIG. First, as shown in FIG. 21A, a filter thin film 27 having filter characteristics is formed on the surface of a transparent substrate 22 such as glass. The substrate 22 on which the filter thin film 27 is formed is prepared for the types of the filters 17a, 17b, 17c, 17d, and 17e. Also prepared is an AR coating layer 21 having the same thickness as the filter thin film 27 formed on the substrate 22.

  Next, as shown in FIG. 21 (b), the back surface of the substrate 22 is polished to reduce the thickness of the substrate 22 as much as possible. As shown in FIG. 21 (c), the filter 17a used in the optical multiplexer / demultiplexer 8d, 17b, 17c, 17d, 17e and the width of the AR coating layer 21 are cut. Filter blocks 29a to 29g are obtained by cutting the substrate 22 on which the filters 17a to 17e or the AR coating layer 21 are formed into a rectangular shape.

  Next, filter blocks 29a to 29e with filters 17a to 17e and filter blocks 29f and 29g with AR coat 21 are arranged in order as shown in FIG. Then, the filter layer 17 as shown in FIG. 21E is completed. The filter layer 17 is bonded to the upper surface of the light guide block 16 with a transparent adhesive.

(Fifth embodiment)
FIG. 22 is a partially cutaway schematic cross-sectional view of an optical multiplexer / demultiplexer 8e according to the fifth embodiment of the present invention, which is similar to FIG. 14 of the first embodiment and FIG. 20 described in the fourth embodiment. It is an equivalent figure. In this optical multiplexer / demultiplexer 8e, the description of the same components as those described in the first or fourth embodiment is omitted. The filters 17a, 17b, 17c, 17d, and 17e are dielectric multilayer films that transmit light having wavelengths λ1, λ2, λ3, λ4, and λ5 and reflect light in other wavelength regions. The filter layer 17 includes filter blocks 29a to 29f in which the filters 17a to 17e or the AR coating layer 21 are formed on the surface of a transparent block such as glass.

  As shown in FIG. 22, the filter layer 17 (filter blocks 29a to 29f) of the optical multiplexer / demultiplexer 8e of this embodiment is disposed only below the microlenses 12a to 12f. As spacers that determine the distance between the microlenses 12a to 12f and the filter layer 17, only spacer blocks 31a and 31b that are completely separate from the microlens array 14 as shown in FIG. 22 may be used. However, as in the optical multiplexer / demultiplexer 8e ′ shown in FIG. 23, the spacers 15a, 15b, 15c, and 15d integrally formed with the microlens array 14 are added to the spacers 15a to 15d so that the height is just right. If the spacer blocks 31a and 31b that can be used are used, the microlens array 14 described in the first embodiment can also be used in this embodiment. In this embodiment, the spacers 15a and 15c and the spacer block 31a are joined, and the spacers 15b and 15d and the spacer block 31b are joined.

  The filter layer 17 of this embodiment can be manufactured with the manufacturing method of the filter layer 17 demonstrated using Fig.21 (a) in 4th Embodiment. However, the filter thin film 27 formed on the upper surface of the substrate 22 shown in FIG. 21 has a tensile stress in the center direction. Therefore, when the back surface of the substrate 22 is polished, the tensile stress causes the glass The substrate may be warped or cracked. In order to solve this problem, as shown in FIG. 24A, after forming a filter thin film 27 on the surface of the substrate 22, the filter thin film 27 is cut with a dicing blade as shown in FIG. Then, after that, as shown in FIG. 24C, the back surface of the substrate 22 may be polished until a desired thickness is obtained. Thus, if the filter thin film 27 is divided before the substrate 22 is polished, the area of each filter thin film 27a is reduced and the stress is relieved. Therefore, even if the substrate 22 is thinned by polishing, the substrate 22 is thinned. Will not warp or crack. Note that the filter thin film 27a does not necessarily have to be divided into the widths of the filters 17a to 17e, and may be divided by a width that is several times the width of the filter so as to relieve the stress.

  Finally, as shown in FIG. 24D, the filter thin film 27a and the substrate 22 are completely cut by the width of the filters 17a to 17e used in the optical multiplexer / demultiplexer 8e. Subsequent steps are the same as those described in the fourth embodiment.

(Sixth embodiment)
FIG. 25 is a partially cutaway schematic cross-sectional view of an optical multiplexer / demultiplexer 8f according to the sixth embodiment of the present invention, and corresponds to FIG. 14 described in the first embodiment. The optical multiplexer / demultiplexer 8f includes an optical fiber array 11, a microlens array 14 having microlenses 12a to 12f and spacers 15a, 15b, 15c, and 15d on the lower surface, a filter layer 17, and a mirror layer 19.

  The filter layer 17 is a filter block 29a, 29b, 29c, 29d, 29e, 29f in which a filter 17a, 17b, 17c, 17d, 17e or an AR coating layer 21 or a dummy film 18b is formed on the surface of a transparent block such as glass. 29g. The filters 17a, 17b, 17c, 17d, and 17e are dielectric multilayer films that transmit light having wavelengths λ1, λ2, λ3, λ4, and λ5 and reflect light in other wavelength regions. In the optical multiplexer / demultiplexer 8f of this embodiment, the filter layer 17 is manufactured by the manufacturing method (FIGS. 21 and 24) described in the fourth or fifth embodiment, and a mirror layer is formed on the back surface of the filter layer 17. 19 is formed.

(Seventh embodiment)
FIG. 26 is a schematic cross-sectional view of an optical multiplexer / demultiplexer 8g according to the seventh embodiment of the present invention, illustrating the structure and the state of demultiplexing an optical signal. This optical multiplexer / demultiplexer 8g has a shape such that two optical multiplexers / demultiplexers described in the first embodiment are arranged symmetrically with the mirror layer 19 in between and integrated.

  The optical multiplexer / demultiplexer 8g of this embodiment includes an optical fiber array 11a composed of optical fibers 9a, 9b, 9c, 9d, 9e, 9f and a connector 10, and microlenses 12a, 12b, 12c, 12d, 12e, 12f on the lower surface. And a microlens array 14a having a spacer 15a, 15b, 15c, 15d, a filter layer 17L, a light guide block 16a, a mirror layer 19, a light guide block 16b, a filter layer 17M, and microlenses 12g, 12h, 12i, 12j on the lower surface. 12k, 12l, a microlens array 14b provided with spacers 15a, 15b, 15c, 15d, an optical fiber array 11b including optical fibers 9g, 9h, 9i, 9j, 9k, 9l and a connector 10.

  The filter layer 17L includes an AR coating layer (antireflection film) 21, filters 17a, 17b, 17c, 17d, and 17e that transmit light having wavelengths λ1, λ2, λ3, λ4, and λ5, a release film 13, and a dummy film ( Spacer) 18b. Among these, the AR coating layer 21 faces the microlens 12a, and the filters 17a to 17e face the microlenses 12b to 12f, respectively. The filter layer 17M includes filters 17f, 17g, 17h, 17i, and 17j that transmit light having wavelengths λ6, λ7, λ8, λ9, and λ10, and dummy films (spacers) 18a and 18b, respectively. Among these, the dummy film 18a faces the micro lens 12g, and the filters 17f to 17j face the micro lenses 12h to 12l, respectively. The mirror layer 19 is formed of a highly reflective material layer such as a metal film, and both surfaces are reflective surfaces. A filter 17k that transmits light of wavelengths λ6, λ7, λ8, λ9, and λ10 is provided in an opening provided in a part of the mirror layer 19.

  Next, the light demultiplexing operation in the optical multiplexer / demultiplexer 8g will be described. The light of wavelengths λ1 to λ10 incident on the microlens 12a from the optical fiber 9a is transmitted through the microlens 12a, the optical path thereof is bent, becomes parallel light, passes through the AR coating layer 21, and the light guide block 16a. The light enters the filter 17k of the mirror layer 19.

  The filter 17k reflects light having wavelengths λ1 to λ5. The reflected lights λ1 to λ5 are repeatedly reflected between the filter layer 17L and the mirror layer 19 while sequentially passing through the filters 17a, 17b, 17c, 17d, and 17e with wavelengths λ1, λ2, λ3, λ4, and λ5. Are transmitted and demultiplexed, and light of wavelengths λ1, λ2, λ3, λ4, and λ5 can be extracted from the optical fibers 9b, 9c, 9d, 9e, and 9f, respectively.

  In addition, the light having the wavelengths λ6 to λ10 that has passed through the filter 17k of the mirror layer 19 passes through the light guide block 16b and enters the filter layer 17M. Here, light of wavelengths λ6, λ7, λ8, λ9, and λ10 is sequentially transmitted through the filters 17f, 17g, 17h, 17i, and 17j while being repeatedly reflected between the filter layer 17M and the mirror layer 19, and is demultiplexed. Light of wavelengths λ6, λ7, λ8, λ9, and λ10 can be extracted from the optical fibers 9h, 9i, 9j, 9k, and 9l, respectively.

  The optical multiplexer / demultiplexer 8g of the present invention is small in size and can be demultiplexed into many wavelengths by sharing the mirror layer 19.

  The optical fibers 9g and 12g may be omitted, but in this embodiment, the optical fibers 9g and 12g are provided in consideration of sharing parts with other embodiments.

(Eighth embodiment)
In any of the first to seventh embodiments, each of the microlenses 12a to 12f of the microlens array 14 includes a part of an aspheric lens that can bend the optical axis direction of light entering and exiting the optical fibers 9a to 9f. Although a lens (that is, a tilted lens) is used, such a lens is not rotationally symmetric around the axis, and becomes a special lens, so that it is difficult to process and mold, and is expensive. . The eighth embodiment takes this point into consideration, and uses a prism to bend the optical axis direction of the light.

  FIG. 27 is an exploded perspective view of an optical multiplexer / demultiplexer 8h according to the eighth embodiment of the present invention, and FIG. 28 is a schematic sectional view thereof. In this optical multiplexer / demultiplexer 8h, end portions of a plurality of optical fibers 9a, 9b, 9c, 9d, 9e, 9f bundled in a row are inserted into the connector 10, and end portions of the optical fibers 9a to 9f are inserted. Are held in parallel by a plastic connector 10. On the lower surface of the optical fiber array 11, end faces of the optical fibers 9a to 9f are exposed in a row. A panel-shaped microlens array 34 is bonded to the lower surface of the connector 10. On the surface of the microlens array 34, a plurality of microlenses 35a, 35b, 35c, 35d, 35e, and 35f are formed in a line. The micro lenses 35a to 35f are lenses (hereinafter referred to as the optical axis direction of the light after passing through the lens (the traveling direction of the light beam passing through the center of the cross section of the light beam) coincident with the optical axis direction of the light before entering the lens. Is called a straight-ahead lens.) In such a straight-ahead lens, a light beam incident on the optical axis of the lens is a general lens that is emitted so as to pass on the optical axis of the lens, and a spherical surface having a rotationally symmetric shape around the optical axis. There are lenses, aspherical lenses, anamorphic lenses, and the like, which are easier to design and manufacture and less expensive than tilted lenses.

  The arrangement pitch of the microlenses 35a to 35f is equal to the arrangement pitch of the optical fibers 9a to 9f, and the microlenses 35a to 35f are arranged so that their optical axes coincide with the optical fibers 9a to 9f, respectively. Further, the thickness of the microlens array 34 is determined so that the end faces of the optical fibers 9a to 9f are positioned substantially at the focal points of the microlenses 35a to 35f.

  Immediately below the microlens array 34 attached to the optical fiber array 11, a multiplexing / demultiplexing block 36 including a prism block 37, a filter layer 17, and a light guide block 16 is disposed. The prism block 37 is a block having a substantially rectangular shape made of glass or transparent plastic material. As shown in FIG. 29, spacers 38 protrude from both ends of the upper surface, and between the spacers 38, microlenses are provided. A plurality of prisms 39a, 39b, 39c, 39d, 39e, and 39f having a triangular cross section at a pitch equal to 35a to 35f are provided. Each prism 39a to 39f has an equal inclination angle, among which the prisms 39b to 39f are inclined in the same direction, and only the prism 39a is inclined in the opposite direction to the other prisms 39b to 39f. The spacer 38 and the prisms 39a to 39f extend on the upper surface of the prism block 37 with the same cross-sectional shape in the front-rear direction. In the prism block 37 shown in FIG. 29, the spacers 38 protrude from both ends of the upper surface. However, as shown in FIG. 42, the spacers 38 are formed around the upper surface of the prism block 37, and the spacers 38 are formed. A plurality of prisms 39a to 39f may be provided in a recess provided in a region surrounded by.

  The filter layer 17 is configured by arranging a plurality of filters 17a, 17b, 17c, and 17d between a pair of dummy films 18a and 18b with transmission wavelength ranges of λ1, λ2, λ3, and λ4 (see FIG. 8). Yes. The filters 17a to 17d are formed to have a width equal to the pitch of the micro lenses 35a to 35f, and the thickness of the dummy films 18a and 18b is equal to the thickness of the filters 17a to 17d in order to make the thickness of the filter layer 17 uniform. Yes. In addition, the filters 17a to 17d and the dummy films 18a and 18b may be pasted and integrated on a thin transparent resin film (not shown) in advance. In addition, a release layer made of a polyimide film or the like may be present under each of the filters 17a to 17d, and an AR coat layer may be formed on the surface of the prism block 37.

  The light guide block 16 is formed in a rectangular shape using glass, quartz, or a transparent plastic material, and a mirror layer 19 made of a dielectric multilayer film or a metal vapor deposition film having a high reflectance is formed on the lower surface thereof.

  In the multiplexing / demultiplexing block 36, as shown in FIG. 30, the filter layer 17 is sandwiched between the lower surface of the prism block 37 and the upper surface of the light guide block 16, and the prism block 37 and the light guide block 16 are joined and integrated. It is formed by doing. In this embodiment, since the dummy films 18a and 18b having the same thickness as the filters 17a to 17d are used, the surface of the filter layer 17 becomes flat and the prism block 37 can be easily joined. The multiplexing / demultiplexing block 36 is disposed close to the bottom of the microlens array 14, and the prisms 39a to 39f are opposed to the microlenses 35a to 35f, respectively. As a result, the microlenses 35a to 35f, the filter layer 17 and the mirror layer 19 are arranged in parallel to each other.

  In the optical multiplexer / demultiplexer 8h assembled in this way, the light emitted from the optical fiber 9a is converted into parallel light by the microlens 35a, refracted by the prism 39a and enters the prism block 37, and the mirror layer 19 Head to. Conversely, the parallel light that is reflected by the mirror layer 19 and then travels toward the prism 39a is refracted by the prism 39a and travels parallel to the optical axis of the optical fiber 9a, and is collected by the microlens 35a and coupled to the optical fiber 9a. It is done. The dummy film 18a is located on the optical path of this light.

  The light emitted from the optical fiber 9 c is converted into parallel light by the micro lens 35 c, refracted by the prism 39 c, enters the prism block 37, and travels toward the mirror layer 19. Conversely, the parallel light that is reflected by the mirror layer 19 and then travels toward the prism 39c is refracted by the prism 39c, travels parallel to the optical axis of the optical fiber 9c, is condensed by the microlens 35c, and is coupled to the optical fiber 9c. It is done. The filter 17a is located on the optical path of this light.

  Similarly, light emitted from the optical fibers 9d to 9f is converted into parallel light by the micro lenses 35d to 35f, refracted by the prisms 39d to 39f, enters the prism block 37, and travels toward the mirror layer 19. On the contrary, the parallel light that is reflected by the mirror layer 19 and then travels toward the prisms 39d to 39f is refracted by the prisms 39d to 39f and travels in parallel with the optical axes of the optical fibers 9d to 9f, and is collected by the microlenses 35d to 35f. It is emitted and coupled to the optical fibers 9d to 9f. The filters 17b, 17c, and 17d are located on the optical paths of these lights, respectively.

  The interval between the positions that pass through the filters 17 a to 17 d and return to the plane on which the prism is formed can be adjusted by the thickness of the light guide block 16. The horizontal distance between the position where the light passes through the prism 39a and the position where the light is reflected by the mirror layer 19 and passes through the filter 17a and returns to the plane on which the prism is formed is adjusted by the thickness of the prism block 37. be able to. Therefore, by adjusting the thickness of the prism block 37 and the thickness of the light guide block 16, the light returning to the prisms 39c to 39f can be adjusted to coincide with the positions of the prisms 39c to 39f.

  Next, the light demultiplexing operation in the optical multiplexer / demultiplexer 8h will be described with reference to FIG. When light of wavelengths λ1, λ2, λ3, and λ4 is emitted from the optical fiber 9a, the light that has entered the microlens 35a from the optical fiber 9a is converted into parallel light by the microlens 35a and then enters the prism 39a. The light incident on the prism 39a is bent in the optical axis direction when passing through the prism 39a, enters obliquely into the prism block 37, passes through the dummy film 18a and the light guide block 16, and reaches the mirror layer 19. Light having wavelengths λ1, λ2, λ3, and λ4 reflected by the mirror layer 19 passes through the light guide block 16 again and reaches the filter 17a. Of the light incident on the filter 17a, the light having the wavelength λ1 passes through the filter 17a and enters the prism 39c, and the optical axis is bent when passing through the prism 39c, and is coupled to the optical fiber 9c by the microlens 35c. Is done. Therefore, only the light of wavelength λ1 can be extracted from the light emitting end of the optical fiber 9c.

  On the other hand, the light of the wavelengths λ2, λ3, and λ4 reflected by the filter 17a is reflected again by the mirror layer 19 and enters the filter 17b. Of the light incident on the filter 17b, the light of wavelength λ2 is transmitted through the filter 17b and incident on the prism 39d, and the optical axis direction is bent when passing through the prism 39d, and is coupled to the optical fiber 9d by the microlens 35d. The Therefore, the light of wavelength λ2 can be extracted from the light emitting end of the optical fiber 9d.

  Similarly, light of wavelengths λ3 and λ4 reflected by the filter 17b is further reflected by the mirror layer 19 and enters the filter 17c. Of the light incident on the filter 17c, the light of wavelength λ3 is transmitted through the filter 17c and incident on the prism 39e, and the optical axis direction is bent when passing through the prism 39e, and is coupled to the optical fiber 9e by the microlens 35e. The Accordingly, light having a wavelength λ3 can be extracted from the light emitting end of the optical fiber 9e.

  Further, the light of wavelength λ4 reflected by the filter 17c is further reflected by the mirror layer 19 and enters the filter 17d. The light of wavelength λ4 transmitted through the filter 17d is incident on the prism 39f, bent in the optical axis direction when transmitted through the prism 39f, and coupled to the optical fiber 9f by the microlens 35f. Therefore, the light of wavelength λ4 can be extracted from the light emitting end of the optical fiber 9f.

  In this way, the optical multiplexer / demultiplexer 8h can demultiplex the multiplexed light. On the contrary, if the light of the wavelengths λ1 to λ4 propagated through the optical fibers 9c to 9f is multiplexed and taken out from the optical fiber 9a, it can be used as a multiplexer (see FIG. 15).

  Here, a joining method when the multiplexing / demultiplexing block 36 is manufactured will be described. When assembling the multiplexing / demultiplexing block 36, as shown in FIG. 30, the filter layer 17 is sandwiched between the prism block 37 and the light guide block 16, and these are bonded to each other with a transparent adhesive and integrated. Good. Alternatively, the dummy film 18a, the filters 17a to 17d, and the dummy film 18b may be arranged in order on the upper surface of the light guide block 16 and bonded with an adhesive, and the lower surface of the prism block 37 may be bonded with the adhesive from above. At this time, if the end of the dummy film 18a or the dummy film 18b is aligned with the end of the lower surface of the prism block 37, the filters 17a to 17d can be positioned according to the width of the dummy film 18a or 18b.

  Moreover, as shown to Fig.31 (a), without using dummy films 18a and 18b, it is only filter 17a-17d (The filter 17a-17d may be affixed on a thin transparent resin film.) Filter layer 17 may be formed, and this may be sandwiched between the prism block 37 and the light guide block 16 and adhered by the adhesive 40. In this case, the gap between the prism block 37 and the light guide block 16 outside the filter layer 17 is filled with the adhesive 40.

  Alternatively, as shown in FIG. 32A, the area of the filter layer 17 is made smaller than the areas of the lower surface of the prism block 37 and the upper surface of the light guide block 16, and the filter layer 17 is formed as shown in FIG. As shown in FIG. 32 (c), the prism block 37 is overlaid on the light guide block 16 without using an adhesive. The lower surface of the prism block 37 and the upper surface of the light guide block 16 may be joined, and the filter layer 17 may be sandwiched between the prism block 37 and the light guide block 16. As a method of bonding the prism block 37 and the light guide block 16 without using an adhesive, a pressure bonding method in which pressure is applied, a low temperature fusion method in which low temperature heat is applied, a ultrasonic bonding method, or the like is used. be able to.

  In the example shown in FIG. 30, the filters 17a to 17d are positioned according to the width of the dummy film 18a or the dummy film 18b. However, the filter layer 17 is positioned on the upper surface of the light guide block 16 as shown in FIG. A groove 41 may be provided. That is, the groove 41 provided on the upper surface of the light guide block 16 has a width substantially equal to the width of the filter layer 17 and a depth substantially equal to the thickness of the filter layer 17. The filter layer 17 can be easily positioned by storing the layer 17 and bonding the prism block 37 to the upper surface of the light guide block 16.

  Similarly, as shown in FIG. 34, a groove 42 is provided on the lower surface of the prism block 37, the filter layer 17 is placed in the groove 42, and the light guide block 16 is joined to the lower surface of the prism block 37. In addition, the filter layer 17 can be positioned. From the standpoint of positioning the prisms 39a to 39f and the filter layer 17, it is preferable to provide the groove 42 in the prism block 37.

  Alternatively, as shown in FIG. 35, when the stepped portion 43 is provided on the lower surface of the prism block 37 and the stepped portion 44 is provided on the upper surface of the light guide block 16, and the prism block 37 and the light guide block 16 are joined. The filter layer 17 may be positioned by placing the filter layer 17 in a space formed between the step portions 43 and 44. In such a structure, if the filter layer 17 is bonded to one stepped portion 43 or the stepped portion 44 and then the prism block 37 and the light guide block 16 are joined, the groove 41 as shown in FIG. 33 or FIG. Alternatively, the positioning of the filter layer 17 can be facilitated rather than storing the filter layer 17 in 42.

  Next, a method of manufacturing the multiplexing / demultiplexing block 36 used in the optical multiplexer / demultiplexer 8h according to this embodiment will be described. First, a method for manufacturing a mold for forming the prism block 37 will be described with reference to FIGS. First, plates 45a, 45b, 45c, 45d, 45e, and 45f made of a metal plate such as stainless steel, aluminum, and brass are prepared in a number equal to the number of prisms 39a to 39f. These plates 45a to 45f have a thickness equal to the pitch of the prisms 39a to 39f, a width equal to the width of the prism block 37, and the surface thereof is mirror-finished. As shown in FIG. 36 (a), these plates 45a to 45f are brought into close contact with each other and are integrated by pressing them with a jig or the like so as not to be displaced from each other. In this state, the end surfaces of these plates 45a to 45f are obliquely ground along the surface indicated by the broken line in FIG. 36A, and the ground surfaces are mirror-finished. Thus, as shown in FIG. 36 (b), the end surfaces of the plates 45a to 45f can be ground at a time, and variations in the grinding angles of the end surfaces of the plates 45a to 45f can be suppressed. Thus, the inclination of the inclined surface 46 formed on the end surfaces of the plates 45a to 45f is equal to the inclination of the prisms 39a to 39f when the inclined surface 46 is directed downward.

  Next, as shown in FIG. 36C, the uppermost 45a is turned over and overlapped, and the inclined surfaces 46 side are aligned, and the plates 45a to 45f are aligned again. In this state, a reverse pattern of the pattern of the prism formation region on the surface of the prism block 37 is formed by the entire inclined surface 46 of each of the plates 45a to 45f. In this state, the plates 45a to 45f are again pressed and integrated with a jig or the like, and then the end surface opposite to the inclined surface 46 is vertically ground along the surface indicated by the broken line in FIG. Align these end faces to a plane. As a result, as shown in FIG. 37D, a prism pattern forming partial mold 47 having a width of one prism block 37 is obtained. As shown in FIG. 37 (e), the prism pattern forming partial mold 47 obtained as described above is arranged in a side-by-side arrangement and integrated.

  Next, as shown in FIG. 38 (a), metal blocks 48 having a width equal to the width of the prism block 37 are arranged in close contact with each other, and the end surfaces thereof are processed as shown in FIG. Get 50. The shape of the processed surface 49 of the molding block 50 is an inverted shape of the shape of the region outside the prism formation region (the spacer 38 and the concave portion adjacent thereto) on the upper surface of the prism block 37. These molding blocks 50 are also arranged and integrated so as to be in close contact with the arrangement number of the prism pattern molding partial molds 47.

  Further, both surfaces of the prism pattern molding partial mold 47 are integrated by sandwiching them with a molding block 50 to obtain a partial mold 51 as shown in FIG. As a method of integrating the parts (plates, molding blocks) constituting the partial mold 51, mechanical integration is achieved by pressing with an appropriate jig (clamper, bolt, nut, etc.). You may adhere using a heat resistant adhesive. Further, when the finishing accuracy of the surface of each component is high, the plates 45a and the molding block 50 are simply joined and integrated together.

  The partial mold 51 shown in FIG. 39 is inserted into the mold body 52 as shown in FIG. 40, and a cavity 53 for molding the prism block 37 between the partial mold 51 and the mold body 52 is provided. It is formed. The mold body 52 is fixed to a stationary platen of the molding machine, and the partial mold 51 is attached to a lifting plate of the molding machine. Accordingly, the partial die 51 is lowered and inserted into the die body 52, and the resin is injected into the cavity 53 from the gate port 54, whereby the prism block 37 is formed. The molded prism block 37 is taken out from the mold body 52 by raising the partial mold 51 and removing it from the mold body 52 and then pushing it up with the ejector pins 55.

  FIG. 41A is a perspective view showing a plurality of prism blocks 37 formed as described above. FIG. 41A shows a light guide block 16 in which a groove 41 for accommodating the filter layer 17 is formed (when a groove is provided like the light guide block 16 in FIG. 33). Although a description of the forming process of the light guide block 16 is omitted, a plurality of the light guide blocks 16 are also formed integrally with the prism block 37, and a mirror layer 19 is formed on the lower surface. The filter layer 17 having a plurality of lengths is accommodated in the grooves 41 of the plurality of light guide blocks 16, and the light guide block 16 and the prism block 37 are joined and integrated as shown in FIG. Thus, a plurality of multiplexing / demultiplexing blocks 36 are obtained.

  In a plurality of multiplexing / demultiplexing blocks 36 formed by using the partial mold 51 as shown in FIG. 39, as shown by a broken line in the multiplexing / demultiplexing block 36 in FIG. Since traces 56 corresponding to the mating surfaces of the partial molds 47 for molding are generated, the individual multiplexing / demultiplexing blocks 36 are obtained by cutting the multiplexing / demultiplexing blocks 36 with a dicing saw or the like along the traces 56. It is done.

  Here, a plurality of multiplexing / demultiplexing blocks 36 are formed at a time to increase mass productivity, but it is of course possible to mold the multiplexing / demultiplexing blocks 36 one by one. In addition, the mirror layer 19 may be formed on the rear surface after the multiplexing / demultiplexing block 36 is assembled.

  As a modification of this embodiment, although not shown, filters 17a, 17b, 17c, and 17d are pasted on the surfaces of the prisms 39c, 39d, 39e, and 39f, respectively, and the mirror layer 19 is formed on the lower surface of the prism block 37. You may do it. This modification is an optical multiplexer / demultiplexer of the same type as the optical multiplexer / demultiplexer 8b shown in FIG. 17 (or see FIG. 44).

  In the case of the optical multiplexer / demultiplexer 8h having the structure as shown in FIG. 27, the second prism 39b may not be provided. However, in this embodiment, the prism 39b is provided in consideration of sharing with the prism block used in the case of the above modification.

(Ninth embodiment)
The optical multiplexer / demultiplexer according to the ninth embodiment of the present invention consolidates the microlenses 35a to 35f and the prisms 39a to 39f into the microlens array 14 attached to the optical fiber array 11, and forms the shape of the multiplexing / demultiplexing block 36. Is characterized by simplification. 43 is a cross-sectional view of the optical multiplexer / demultiplexer 8i according to the ninth embodiment. Except for the structure of the microlens array 14, the structure similar to that of the first embodiment shown in FIG. Have.

  In the microlens array 14 used in this embodiment, as shown in FIG. 44A, a concave portion 57 is formed on the back surface of the microlens array 14, and a plurality of microlenses 35a, which are linearly moving lenses, are formed in the concave portion 57. -35f are formed in a line. Also, as shown in FIG. 44B, a recess 58 is also formed on the surface of the microlens array 14, and prisms 39 a to 39 f are formed in a row in the recess 58. The prisms 39a to 39f and the microlenses 35a to 35f formed on the front and back sides of the microlens array 14 correspond to each other on a one-to-one basis, and the labor for positioning the prisms 39a to 39f and the microlenses 35a to 35f can be saved. .

  Thus, since the prisms 39a to 39f are provided in the microlens array 14, the multiplexing / demultiplexing block 36 includes a simple rectangular block (cover member 20) in which the prisms 39a to 39f are not provided, the filter layer 17, and the like. The light guide block 16 is used.

  The optical multiplexer / demultiplexer 8i having such a structure can also function as a demultiplexer and a multiplexer as in the eighth embodiment.

  Further, when such a microlens array 14 as shown in FIGS. 44A and 44B is used, a space is generated between the microlens array 14 and the multiplexing / demultiplexing block 36, and therefore the filter layer 17 is formed in this space. Can be arranged. Therefore, as shown in FIG. 45, an optical multiplexer / demultiplexer in which the filter layer 17 is disposed on the surface of the light guide block 16 and the mirror layer 19 is provided on the back surface of the light guide block 16 can be obtained. This is because light is incident on the light guide block 16 at an angle to reflect light between the filters 17a to 17e and the mirror layer 19 and light of wavelengths λ1, λ2, λ3, λ4, and λ5 sequentially from the filters 17a to 17e. And has the same structure as the optical multiplexer / demultiplexer 8b shown in FIG. 17 except for the structure of the microlens array 14.

(Tenth embodiment)
FIG. 46 is a sectional view showing the structure of an optical multiplexer / demultiplexer 8j according to the tenth embodiment of the present invention. The optical multiplexer / demultiplexer 8j has the same structure as the optical multiplexer / demultiplexer 8b according to the first embodiment shown in FIG.

  In this embodiment, microlenses 35 a and 35 c to 35 f are formed by arranging aspherical or spherical rectilinear lenses in a line on the surface of the microlens array 14. There is a gap between the micro lens 35a and the micro lenses 35c to 35f. The microlenses 35a and 35c to 35f are arranged with their optical axes shifted from the optical axis directions of the optical fibers 9a and 9c to 9f. The microlens 35a is eccentric to the microlens 35c side, The lenses 35c to 35f are decentered toward the microlens 35a as a whole.

  Thus, although the tilt lens is not used in the microlens array 14, the optical axes of the microlenses 35a and 35c to 35f, which are straight traveling lenses, are shifted from the optical axes of the optical fibers 9a and 9c to 9f. Light emitted from each of the optical fibers 9a, 9c to 9f is converted into parallel light by passing through the microlenses 35a and 35c to 35f, and the light emission direction is bent obliquely. Further, when the parallel light emitted from the multiplexing / demultiplexing block 36 is obliquely incident on each of the micro lenses 35a, 35c to 35f, the light traveling direction is transmitted through the micro lenses 35a, 35c to 35f, so that the optical fiber 9a, The light is bent in a direction parallel to the optical axis of 9c to 9f and condensed on the end faces of the optical fibers 9a and 9c to 9f.

  Therefore, even in the optical multiplexer / demultiplexer 8j, the demultiplexing operation and the multiplexing operation can be performed in the same manner as the optical multiplexer / demultiplexer 8a according to the first embodiment.

(Eleventh embodiment)
FIG. 47 is an exploded perspective view showing an optical multiplexer / demultiplexer 8k according to the eleventh embodiment of the present invention. In this optical multiplexer / demultiplexer 8k, the optical fiber array 11 is configured by holding the distal ends of two parallel optical fiber bundles of optical fibers 9a to 9f and optical fibers 59a to 59f by a connector 10. . Here, if the optical fibers 9a to 9f and the optical fibers 59a to 59f are arranged in order from the opposite side as shown in FIG. 47, the optical fiber 9c and the optical fiber 59e face each other in the front-rear direction, and the optical fiber 9d. And the optical fiber 59d face each other in the front-rear direction, and the optical fiber 9e and the optical fiber 59c face each other in the front-rear direction. The microlens array 14 is provided with microlenses 12a and 12c to 12f corresponding to the end faces of the optical fibers 9a and 9c to 9f, and the microlenses 60a and 12c are provided corresponding to the end faces of the optical fibers 59a and 59c to 59f. 60c-60f are provided. In the multiplexing / demultiplexing block 36, the filter layer 17 including the filters 17a to 17d is sandwiched between the light guide block 16 having the mirror layer 19 formed on the back surface and the cover member 20.

  FIG. 48 is a cross-sectional view taken along a plane including the optical fibers 9a to 9f. The optical multiplexer / demultiplexer 8k functions as a demultiplexer in this cross section, and the multiplexed optical signals having wavelengths λ1, λ2, λ3, and λ4 incident from the optical fiber 9a are demultiplexed by the optical multiplexer / demultiplexer 8k, and the wavelength λ1 The optical signal of wavelength λ2 enters the optical fiber 9d, the light of wavelength λ3 enters the optical fiber 9e, and the optical signal of wavelength λ4 enters the optical fiber 9f. The demultiplexing operation at this time is as described in the first embodiment (see the description of FIG. 14).

  FIG. 49 is a sectional view taken along a plane including the optical fibers 59a to 59f. The optical multiplexer / demultiplexer 8k functions as a multiplexer in this cross section, and enters the optical signal of wavelength λ1 incident from the optical fiber 59f, the optical signal of wavelength λ2 incident from the optical fiber 59e, and the optical fiber 59d. The optical signal of wavelength λ3 and the optical signal of wavelength λ4 incident from optical fiber 59c are multiplexed by optical multiplexer / demultiplexer 8k, and multiplexed optical signals of wavelengths λ1, λ2, λ3, and λ4 are transmitted to optical fiber 59a. Incident. The multiplexing operation at this time is as described in the first embodiment (see the description of FIG. 15).

  Therefore, in this optical multiplexer / demultiplexer 8k, as shown in FIG. 50, the optical fiber 9a-9f, the microlenses 12a, 12c-12f, and a part of the filter layer 17 constitute a demultiplexing unit, and the optical fiber 59a ˜59f, microlenses 60a, 60c˜60f, and a part of the filter layer 17 constitute a multiplexing unit, and the demultiplexing unit and the multiplexing unit share the filters 17a-17d.

  FIG. 51 is a schematic diagram for explaining the usage state of the optical multiplexer / demultiplexer 8k. An optical multiplexer / demultiplexer 8k installed in one station and an optical multiplexer / demultiplexer 8k installed in the other station are connected by two-core optical fiber cables 61 and 62. That is, the optical fiber cable 61 includes the optical fiber 59a in the multiplexing unit of the optical multiplexer / demultiplexer 8k installed in one station and the optical fiber 9a in the demultiplexing unit of the optical multiplexer / demultiplexer 8k installed in the other station. And the optical fiber 59a of the multiplexing unit of the optical multiplexer / demultiplexer 8k installed in the other station and the optical fiber 9a of the demultiplexing unit of the optical multiplexer / demultiplexer 8k installed in the one station Are connected by an optical fiber cable 62.

  Therefore, in one of the stations, the optical signals having the wavelengths λ1, λ2, λ3, and λ4 are multiplexed by the optical multiplexer / demultiplexer 8k and multiplexed, and the optical signals having the wavelengths λ1 to λ4 are multiplexed by the single optical fiber cable 61. Transmit to the other station. In the optical multiplexer / demultiplexer 8k of the other station that has received the multiplexed optical signal, the multiplexed optical signal is demultiplexed by the optical multiplexer / demultiplexer 8k, and optical signals having wavelengths λ1, λ2, λ3, and λ4 are obtained. Take out individually. At the same time, in the other station, the optical signals of wavelengths λ1, λ2, λ3, and λ4 are multiplexed by the optical multiplexer / demultiplexer 8k, and the optical signals of wavelengths λ1 to λ4 are multiplexed by one optical fiber cable 62. To the other station. In the optical multiplexer / demultiplexer 8k of one station that has received the multiplexed optical signal, the multiplexed optical signal is demultiplexed by the optical multiplexer / demultiplexer 8k, and optical signals having wavelengths λ1, λ2, λ3, and λ4 are obtained. Take out individually.

  In the embodiment of FIG. 47, the optical fibers 59a to 59f and the micro lenses 60a and 60c to 60f of the multiplexing unit are directed in the opposite direction to the optical fibers 9a to 9f and the micro lenses 12a and 12c to 12f of the demultiplexing unit. Sequentially arranged, light of wavelength λ1 is sequentially multiplexed in the order of light of wavelength λ2, light of wavelength λ3, and light of wavelength λ4. On the contrary, the optical fibers 59a to 59f and the micro lenses 60a and 60c to 60f in the multiplexing unit are sequentially arranged in the same direction as the optical fibers 9a to 9f and the micro lenses 12a and 12c to 12f in the demultiplexing unit. It is also possible to configure such that light of wavelength λ4 is sequentially multiplexed in the order of light of wavelength λ3, light of wavelength λ2, and light of wavelength λ1.

  FIG. 52A shows an optical multiplexer / demultiplexer 8k configured as in the former, and the optical fiber 59a in the multiplexing unit of the optical multiplexer / demultiplexer 8k in one station and the optical multiplexer / demultiplexer 8k in the other station. The state where the optical fiber 9a of the demultiplexing part is connected by the optical fiber cable 61 is shown. FIG. 52 (b) shows an optical multiplexer / demultiplexer 8k of one station and an optical fiber / multiplexer / demultiplexer of the other station using the optical multiplexer / demultiplexer 8k configured as the latter. The state where the optical fiber 9a of the 8k branching part is connected by the optical fiber cable 61 is shown. When comparing the case of FIG. 52A and the case of FIG. 52B, in the case of FIG. 52B, the light of wavelength λ4 is first introduced, and the light of wavelength λ3 is multiplexed there. Next, the light of wavelength λ2 is multiplexed, and then the light of wavelength λ1 is multiplexed and sent to the other station via the optical fiber cable 61. The other station separates the light of wavelength λ1 from the received optical signal. Then, the light of wavelength λ2 is demultiplexed and extracted, the light of wavelength λ3 is demultiplexed and extracted, and finally the light of wavelength λ4 is extracted. Therefore, according to such a configuration, the light having the wavelength λ4 first incident at one station is extracted last at the other station, and the light having the wavelength λ1 finally combined at one station is extracted from the other station. Then, it is first taken out (FILO), and the optical path length from entering the optical multiplexer / demultiplexer 8k of one station to emitting from the optical multiplexer / demultiplexer 8k of the other station differs depending on the wavelength. For this reason, the degree of attenuation differs or the phase differs depending on the wavelength of light, and the characteristics may change depending on the wavelength.

  On the other hand, in the case of FIG. 52A corresponding to the embodiment as shown in FIG. 47, light of wavelength λ1 is first introduced, light of wavelength λ2 is multiplexed there, and then light of wavelength λ3 is combined. Next, the light of wavelength λ4 is multiplexed and sent to the other station by the optical fiber cable 61. The other station demultiplexes and extracts the light of wavelength λ1 from the received optical signal, and then the wavelength The light with wavelength λ2 is demultiplexed and extracted, then the light with wavelength λ3 is demultiplexed and extracted, and finally the light with wavelength λ4 is extracted. Therefore, according to the configuration shown in FIG. 47 and FIG. 52 (a), the light having the wavelength λ1 first incident at one station is first extracted at the other station and finally combined at one station. The light of wavelength λ4 is finally extracted at the other station (FIFO), and the optical path length from the time when it enters the optical multiplexer / demultiplexer 8k of one station to the time when it is emitted from the optical multiplexer / demultiplexer 8k of the other station is It is almost constant regardless of the wavelength. For this reason, the degree of attenuation of the optical signal and the phase do not differ depending on the wavelength, and the transmission characteristics can be made uniform regardless of the wavelength.

  FIG. 53 is an exploded perspective view showing the structure of an optical multiplexer / demultiplexer 8m according to a modification of the eleventh embodiment of the present invention. In this optical multiplexer / demultiplexer 8m, on the surface of the microlens array 14, microlenses 35a and 35c to 35f made of straight lenses and microlenses 73a and 73c to 73f made of straight lenses are arranged in two rows. It is arranged. Further, a multiplexing / demultiplexing block 36 is configured by sandwiching the filter layer 17 between the light guide block 16 having the mirror layer 19 formed on the lower surface and the prism block 37. On the upper surface of the prism block 37, prisms 39a to 39f and prisms 74a to 74f are arranged in two rows. The microlenses 35a and 35c to 35f and the prisms 39a and 39c to 39f serve as the microlenses 12a and 12c to 12f in the optical multiplexer / demultiplexer 8k of FIG. 47. The microlenses 73a and 73c to 73f and the prisms The micro lenses 60a and 60c to 60f function as 74a and 74c to 74f.

  FIG. 54 is an exploded perspective view showing the structure of an optical multiplexer / demultiplexer 8n according to another modification of the eleventh embodiment of the present invention. In this optical multiplexer / demultiplexer 8n, as shown in FIG. 55, on the back surface of the microlens array 14, microlenses 35a and 35c to 35f made of straight lenses, and a microlens 73a made of straight lenses. 73c to 73f are arranged in two rows. In addition, prisms 39 a to 39 f and prisms 74 a to 74 f are arranged in two rows on the surface of the microlens array 14. Further, a multiplexing / demultiplexing block 36 is configured by sandwiching the filter layer 17 between the light guide block 16 having the mirror layer 19 formed on the lower surface and the cover member 20. The microlenses 35a and 35c to 35f and the prisms 39a and 39c to 39f serve as the microlenses 12a and 12c to 12f in the optical multiplexer / demultiplexer 8k of FIG. 47. The microlenses 73a and 73c to 73f and the prisms The micro lenses 60a and 60c to 60f function as 74a and 74c to 74f.

(Twelfth embodiment)
FIG. 56 is a sectional view showing an optical multiplexer / demultiplexer 8p according to the twelfth embodiment of the present invention. In the optical multiplexer / demultiplexer 8k according to the eleventh embodiment, two optical fiber cables 61 and 62 are required to connect the optical multiplexer / demultiplexer 8k. In the twelfth embodiment, one optical fiber is used. The optical multiplexer / demultiplexer 8p can be connected by the cable 61.

  In this optical multiplexer / demultiplexer 8p, the demultiplexing portion and the multiplexing portion are integrally formed. The demultiplexing unit is configured by optical fibers 9a, 9c, 9d, 9e, 9f, microlenses 12a, 12c, 12d, 12e, 12f and filters 17a, 17b, 17c, 17d held in the optical fiber array 11. . Here, the filter 17a has a characteristic of transmitting light of wavelength λ1 and reflecting light of another wavelength range, and the filter 17b has a characteristic of transmitting light of wavelength λ2 and reflecting light of another wavelength range. The filter 17c has a characteristic of transmitting light of wavelength λ3 and reflecting light of another wavelength range, and the filter 17d has a characteristic of transmitting light of wavelength λ4 and reflecting light of another wavelength range.

  The multiplexing unit of the optical multiplexer / demultiplexer 8p includes optical fibers 59a, 59c, 59d, 59e, 59f, micro lenses 60a, 60c, 60d, 60e, 60f and filters 63a, 63b, 63c, which are held in the optical fiber array 11. 63d. Here, the filter 63a has a characteristic of transmitting light of wavelength λ5 and reflecting light of another wavelength range, and the filter 63b has a characteristic of transmitting light of wavelength λ6 and reflecting light of another wavelength range. The filter 63c has a characteristic of transmitting light of wavelength λ7 and reflecting light of another wavelength range, and the filter 63d has a characteristic of transmitting light of wavelength λ8 and reflecting light of another wavelength range.

  The optical fiber 59a of the multiplexing unit is connected to the demultiplexing unit so that the end surface thereof faces the microlens 12b disposed between the microlenses 12a and 12c of the demultiplexing unit. Further, a filter 64 having a characteristic of transmitting light having wavelengths λ1, λ2, λ3, and λ4 and reflecting light having wavelengths λ5, λ6, λ7, and λ8 is disposed in the filter layer 17 at a position adjacent to the filter 17a. Has been.

  In the demultiplexing unit of the optical multiplexer / demultiplexer 8p, when the multiplexed optical signal having the wavelengths λ1, λ2, λ3, and λ4 is emitted from the optical fiber 9a, the optical signal is converted into parallel light by 12a. The optical axis direction is bent and enters the filter 64. The light of wavelengths λ1, λ2, λ3, and λ4 is transmitted through the filter 64 and reflected by the mirror layer 19, and then only the light of wavelength λ1 is transmitted through the filter 17a and is coupled to the optical fiber 9c by the microlens 12c. Further, after the light of wavelengths λ2, λ3, and λ4 reflected by the filter 17a is reflected again by the mirror layer 19, only the light of wavelength λ2 passes through the filter 17b and is coupled to the optical fiber 9d by the microlens 12d. Further, after the light of wavelengths λ3 and λ4 reflected by the filter 17b is reflected again by the mirror layer 19, only the light of wavelength λ3 passes through the filter 17c and is coupled to the optical fiber 9e by the microlens 12e. The light of wavelength λ4 reflected by the filter 17c is reflected again by the mirror layer 19, and then only the light of wavelength λ4 passes through the filter 17d and is coupled to the optical fiber 9f by the microlens 12f.

  Further, in the multiplexing part of the optical multiplexer / demultiplexer 8p, when light of wavelengths λ5, λ6, λ7, λ8 is emitted from the optical fibers 59c, 59d, 59e, 59f, the wavelength emitted from the optical fiber 59f After the light of λ8 is bent in the optical axis direction by the micro lens 60f, the light passes through the filter 63d, is reflected by the mirror layer 19, and enters the filter 63c. On the other hand, the light of wavelength λ7 emitted from the optical fiber 59e passes through the filter 63c after being bent in the optical axis direction by the microlens 60e. Then, the light of wavelength λ7 that has passed through the filter 63c and the light of wavelength λ8 that has been reflected by the filter 63c are reflected by the mirror layer 19 and then enter the filter 63b. On the other hand, the light of wavelength λ6 emitted from the optical fiber 59d passes through the filter 63b after being bent in the optical axis direction by the microlens 60d. Then, the light of wavelength λ6 transmitted through the filter 63b and the light of wavelengths λ8 and λ7 reflected by the filter 63b are reflected by the mirror layer 19 and then enter the filter 63a. On the other hand, the light of wavelength λ5 emitted from the optical fiber 59c passes through the filter 63a after being bent in the optical axis direction by the microlens 60c. Then, the light of wavelength λ5 transmitted through the filter 63a and the light of wavelengths λ8, λ7, and λ6 reflected by the filter 63a are reflected by the mirror layer 19 and then enter the microlens 60a and coupled to the optical fiber 59a.

  The light of wavelengths λ5, λ6, λ7, and λ8 thus incident on the optical fiber 59a propagates through the optical fiber 59a and is emitted from the other end of the optical fiber 59a. Light having wavelengths λ5, λ6, λ7, and λ8 emitted from the other end of the optical fiber 59a is bent by the microlens 12b and then enters the filter 64, is reflected by the filter 64, and enters the microlens 12a. Coupled to fiber 9a.

  As shown in FIG. 57, the optical multiplexer / demultiplexer 8p includes an optical multiplexer / demultiplexer 8p installed in one station and an optical multiplexer / demultiplexer 8p ′ installed in the other station, as one optical fiber cable 61. The optical fiber cable 61 is connected to the optical fiber 9a in any of the optical multiplexers / demultiplexers 8p and 8p ′.

  However, in the optical multiplexer / demultiplexer 8p 'connected to the optical multiplexer / demultiplexer 8p, the arrangement of the filters 17a to 17d and 63a to 63d is different from that of the optical multiplexer / demultiplexer 8p. And have been replaced. That is, in the optical multiplexer / demultiplexer 8p ′, the optical fiber 9a, 9c, 9d, 9e, 9f, the microlenses 12a, 12c, 12d, 12e, 12f and the filters 17a, 17b, 17c, 17d constitute a multiplexing unit. The arrangement of the filters 17a to 17d is opposite to that of the optical multiplexer / demultiplexer 8p.

  In the optical multiplexer / demultiplexer 8p ′, the optical fiber 59a, 59c, 59d, 59e, 59f, the micro lenses 60a, 60c, 60d, 60e, 60f and the filters 63a, 63b, 63c, 63d constitute a demultiplexing unit, The arrangement of the filters 63a to 63d is opposite to that of the optical multiplexer / demultiplexer 8p.

  Thus, after the optical signals of wavelengths λ5 to λ8 are multiplexed by the optical multiplexer / demultiplexer 8p, the multiplexed optical signal is sent to the optical multiplexer / demultiplexer 8p ′ via the optical fiber cable 61, and is then transmitted by the optical multiplexer / demultiplexer 8p ′. Each of the wavelengths λ5 to λ8 is demultiplexed, and optical signals of the wavelengths λ5 to λ8 are extracted. Here, for example, the light of wavelength λ8 is first multiplexed by the optical multiplexer / demultiplexer 8p and first demultiplexed by the optical multiplexer / demultiplexer 8p ′, and the light of wavelength λ5 is finally multiplexed by the optical multiplexer / demultiplexer 8p. Waves are finally demultiplexed by the optical multiplexer / demultiplexer 8p ′, and the transmission distances (optical path lengths) of the optical signals having the wavelengths λ5 to λ8 are equal to each other.

  Similarly, after optical signals having wavelengths λ1 to λ4 are multiplexed by the optical multiplexer / demultiplexer 8p ′, the multiplexed optical signal is sent to the optical multiplexer / demultiplexer 8p through the same optical fiber cable 61, and the optical multiplexer / demultiplexer 8p. Each of the wavelengths λ1 to λ4 is demultiplexed, and optical signals of the wavelengths λ1 to λ4 are extracted. Here, for example, the light of wavelength λ1 is first multiplexed by the optical multiplexer / demultiplexer 8p ′ and first demultiplexed by the optical multiplexer / demultiplexer 8p, and the light of wavelength λ4 is finally terminated by the optical multiplexer / demultiplexer 8p ′. The optical signals are multiplexed and finally demultiplexed by the optical multiplexer / demultiplexer 8p, and the transmission distances (optical path lengths) of the optical signals having the wavelengths λ1 to λ4 are equal to each other.

  In addition, although the multiplexing part and demultiplexing part of optical multiplexer / demultiplexers 8p and 8p 'are arrange | positioned in series in FIG. 56, you may arrange in parallel and arrange in parallel.

  FIG. 58 shows an optical multiplexer / demultiplexer 8q according to a modification of the twelfth embodiment. In the optical multiplexer / demultiplexer 8p, the multiplexing portion and the demultiplexing portion are connected by the optical fiber 59a. However, the optical multiplexer / demultiplexer 8q in FIG. 58 uses the two right-angled triangular concave portions 65 and 66 to combine them. The wave part and the demultiplexing part are connected. That is, in this modification, the upper surface of the cover member 20 is provided with recesses 65 and 66 having a right-angled cross-sectional shape, and the light having wavelengths λ5, λ6, λ7, and λ8 combined at the combiner is recessed. The light is incident on the filter 64 by being totally reflected by 65 and 66, and after being reflected by the filter 64, is coupled to the optical fiber 9a.

  FIG. 59 is a schematic sectional view showing the structure of an optical multiplexer / demultiplexer 8r according to another modification of the twelfth embodiment. In the optical signal demultiplexer 8r, an optical multiplexer / demultiplexer similar to the optical multiplexer / demultiplexer 8p in FIG. 56 is manufactured by the following configuration. Microlenses 35a, 35c-35f made of rectilinear lenses are provided on the lower surface of the microlens array 14 so as to oppose end faces of the optical fibers 9a, 9c-9f, and micros made of rectilinear lenses are made opposed to the end faces of the optical fibers 59c-59f. Lenses 73c to 73f are provided, and microlenses 73a and 35b are provided to face both ends of an optical fiber 59a bent in an inverted U shape. Also, the filter layer 17 is sandwiched between the light guide block 16 having the mirror layer 19 formed on the lower surface and the prism block 37 to constitute a multiplexing / demultiplexing block 36. On the upper surface of the prism block 37, prisms 39a to 39f are formed facing the microlenses 35a to 35f, and prisms 74a, 74c to 74f are formed facing the microlenses 73a and 73c to 73f. Note that the microlens 73b and the prism 74b may be omitted.

(13th Embodiment)
In each of the above embodiments, light of each wavelength is input to an optical multiplexer / demultiplexer using an optical fiber, and light of each wavelength is extracted from the optical multiplexer / demultiplexer using an optical fiber. However, without using an optical fiber, a light emitting element such as a semiconductor laser element (LD) is mounted at a light incident position of the optical multiplexer / demultiplexer, or a light receiving element such as a photodiode (PD) or a phototransistor is mounted on the optical multiplexer / demultiplexer. You may mount in the light emission location.

  For example, an optical multiplexer / demultiplexer (transponder) 8s shown in FIG. 60 is based on the optical multiplexer / demultiplexer 8p shown in FIG. In this case, only the optical fiber 9a for connecting to the optical fiber cable and the optical fiber 59a connecting the multiplexing part and the demultiplexing part are left, and face the microlenses 12c to 12f on the microlens array 14. The light receiving elements 68c, 68d, 68e, and 68f (for example, a light receiving element array in which the light receiving elements are integrated) are mounted, and the light emission wavelengths λ1, λ2, and the like are respectively placed on the microlens array 14 so as to face the microlenses 60c to 60f. Light emitting elements 67c, 67d, 67e, 67f (for example, a light emitting element array in which light emitting elements are integrated) may be mounted. The light receiving elements 68c to 68f are arranged so that the optical axis direction (the maximum sensitivity direction of the light receiving element or the direction perpendicular to the light receiving surface of the light receiving element) faces the direction perpendicular to the filter layer 17, and the light emitting element 67c. ˜67f are arranged such that the direction of the optical axis (the direction in which the light emission intensity is maximum or the direction perpendicular to the light emitting surface of the light emitting element) faces the direction perpendicular to the filter layer 17.

  According to the optical multiplexer / demultiplexer 8s configured as described above, the light emitting elements 67c to 67f can be driven to directly multiplex the optical signals, and the light signals can be directly received by the light receiving elements 68c to 68f. be able to. Here, if a light receiving element array is used as the light receiving elements 68c to 68f, the cost can be reduced as compared with the case of using individual elements. In that case, if the light receiving element array can be mounted without being inclined as in the present invention, An element with a long optical path length can prevent an increase in insertion loss and an increase in the size of the optical multiplexer / demultiplexer. The same applies to the light emitting elements 67c to 67f.

  FIG. 61 is a schematic sectional view showing the structure of an optical multiplexer / demultiplexer 8t according to a modification of the thirteenth embodiment. In the optical signal demultiplexer 8t, a transponder similar to the optical multiplexer / demultiplexer 8s in FIG. 60 is manufactured by the following configuration. On the lower surface of the microlens array 14, microlenses 35 a and 35 c to 35 f made of rectilinear lenses are provided facing the optical fibers 9 a and the light receiving elements 68 c to 68 f, and micros made of rectilinear lenses are made to face the light emitting elements 67 c to 67 f. Lenses 73c to 73f are provided, and microlenses 73a and 35b are provided to face both ends of an optical fiber 59a bent in an inverted U shape. Also, the filter layer 17 is sandwiched between the light guide block 16 having the mirror layer 19 formed on the lower surface and the prism block 37 to constitute a multiplexing / demultiplexing block 36. On the upper surface of the prism block 37, prisms 39a to 39f are formed facing the microlenses 35a to 35f, and prisms 74a, 74c to 74f are formed facing the microlenses 73a and 73c to 73f.

(Fourteenth embodiment)
FIG. 62 is a sectional view showing an optical multiplexer / demultiplexer (transponder) 8u according to the fourteenth embodiment of the present invention. In this embodiment, the microlenses 12a, 12c, 12d, 12e, and 12f are provided on the lower surface of the light guide plate 70, the optical fiber 71 is connected to the upper surface of the light guide plate 70 so as to face the microlens 12a, and the microlenses 12c to 12d. The light emitting elements 67c, 67d, 67e, 67f (for example, a light emitting element array in which the light emitting elements are integrated) having light emission wavelengths λ1, λ2, λ3, and λ4 are mounted on the light guide plate 70 so as to face each other. A multiplexing / demultiplexing block 36 configured for multiplexing is arranged below 12f. A filter 64 is embedded in the light guide plate 70 at an angle of 45 degrees between the end face of the optical fiber 71 and the microlens 12a. The light guide plate 70 is longer than the width of the multiplexing / demultiplexing block 36. In the region of the light guiding plate 70 that protrudes from the multiplexing / demultiplexing block 36, the upper surface of the light guide plate 70 transmits only light of wavelength λ5. An element 72a, a diffractive element 72b that transmits only light of wavelength λ6, a diffractive element 72c that transmits only light of wavelength λ7, and a diffractive element 72d that transmits only light of wavelength λ8 are formed on each of the diffractive elements 72a to 72d. Are mounted with light receiving elements 68c to 68f (for example, a light receiving element array in which the light receiving elements are integrated). The light emitting elements 67c to 67f are arranged so that the optical axis direction thereof is oriented in a direction perpendicular to the filters 17a to 17d or the light guide plate 70. The light receiving elements 68c to 68f also have optical axis directions thereof corresponding to the filters 17a to 17d. It is arranged to face the vertical direction.

  Thus, the light beams having the wavelengths λ1, λ2, λ3, and λ4 emitted from the light emitting elements 67c to 67f are multiplexed by the multiplexing / demultiplexing block 36 and emitted from the multiplexing / demultiplexing block 36, and are emitted by the microlens 12a. After being bent in the axial direction, the light passes through the filter 64 and is coupled to the optical fiber 71 and transmitted from the optical fiber 71. Further, the multiplexed transmission signals of wavelengths λ5, λ6, λ7, and λ8 received from the optical fiber 71 are reflected by the filter 64 to the projecting side of the light guide plate 70, and are repeatedly totally reflected on the upper and lower surfaces of the light guide plate 70. It propagates through 70. When light propagating through the light guide plate 70 enters the diffraction element 72a, only light having the wavelength λ5 is transmitted through the diffraction element 72a and received by the light receiving element 68c. When light propagating through the light guide plate 70 is incident on the diffraction elements 72b, 72c, or 72d, only the light with the wavelength λ6, λ7, or wavelength λ8 is transmitted through the diffraction elements 72b, 72c, or 72d, respectively, and the light receiving element 68d. 68e and 68f. In addition to the diffraction grating, a CGH element or the like can be used as the diffraction element.

  FIG. 63 is a schematic sectional view showing the structure of an optical multiplexer / demultiplexer 8v according to a modification of the fourteenth embodiment. In the optical signal demultiplexer 8v, a transponder similar to the optical multiplexer / demultiplexer 8u in FIG. 62 is manufactured by the following configuration. On the lower surface of the microlens array 14, microlenses 35 a and 35 c to 35 f made of a rectilinear lens are provided facing the optical fiber 71 and the light emitting elements 67 c to 67 f. Also, the filter layer 17 is sandwiched between the light guide block 16 having the mirror layer 19 formed on the lower surface and the prism block 37 to constitute a multiplexing / demultiplexing block 36. On the upper surface of the prism block 37, prisms 39a, 39c to 39f are formed facing the micro lenses 35a and 35c to 35f.

(The invention's effect)
The optical multiplexer / demultiplexer according to the present invention includes a deflection element including a lens, a prism, and the like, and can bend the optical axis direction of light by the deflection element. Therefore, transmission means such as an optical fiber that propagates multiplexed light, an optical fiber that propagates the light after demultiplexing, a light receiving element that receives the light after demultiplexing, or a light emitting element that emits the light before multiplexing The surface on which the light input / output means such as the above are arranged in parallel, the surface on which the wavelength selection elements are arranged, and the light reflecting surface can be arranged in parallel to each other, and the manufacturing is easy, and the demultiplexing or multiplexing Even if the number of wavelengths to be increased is increased, a small optical multiplexer / demultiplexer can be obtained.

It is the schematic for demonstrating the structure of the optical multiplexer / demultiplexer by a prior art example. 1 is an exploded perspective view showing a structure of an optical multiplexer / demultiplexer according to a first embodiment of the present invention. It is a schematic sectional drawing in the surface which passes along the core of each optical fiber array of the optical multiplexer / demultiplexer by 1st Embodiment. It is a side view of the optical multiplexer / demultiplexer by 1st Embodiment. It is a bottom view of a micro lens array. It is explanatory drawing explaining the optical path of the light radiate | emitted from an optical fiber and injects into another optical fiber. (A) and (b) are the top view and front view explaining the shape of a micro lens. It is a figure which shows the characteristic of each filter, the characteristic of a dummy film, and AR coating layer, Comprising: A horizontal axis shows the wavelength of light and a vertical axis | shaft shows the light transmittance. (A)-(e) is a figure explaining the manufacturing process of a filter layer. (F) (g) is a figure explaining the process after FIG.9 (e). It is a figure explaining the manufacturing method of a filter layer. (A)-(d) is a figure explaining another manufacturing process of a filter layer. (E)-(g) is a figure explaining the process after FIG.12 (d). It is a schematic sectional drawing explaining the demultiplexing operation | movement of the optical multiplexer / demultiplexer by 1st Embodiment. It is a schematic sectional drawing explaining the multiplexing operation | movement of the optical multiplexer / demultiplexer by 1st Embodiment. It is a schematic sectional drawing which shows the state which put the optical multiplexer / demultiplexer of this invention in the casing. It is the schematic sectional drawing which the optical multiplexer / demultiplexer by the 2nd Embodiment of this invention fractured | ruptured partially. It is the schematic sectional drawing which fractured | ruptured partially which shows the modification of the 2nd Embodiment of this invention. FIG. 6 is a schematic cross-sectional view of a partially broken optical multiplexer / demultiplexer according to a third embodiment of the present invention. It is the schematic sectional drawing to which the optical multiplexer / demultiplexer by the 4th Embodiment of this invention was fractured | ruptured partially. (A)-(e) is a figure explaining the manufacturing method of the filter layer used for embodiment same as the above. It is the schematic sectional drawing which a part fracture | ruptured of the optical multiplexer / demultiplexer by the 5th Embodiment of this invention. It is the schematic sectional drawing which fractured | ruptured partially which shows the modification of the 5th Embodiment of this invention. (A)-(d) is a figure explaining the manufacturing process of the filter layer used for the optical multiplexer / demultiplexer by 5th Embodiment. FIG. 10 is a schematic sectional view, partly broken, of an optical multiplexer / demultiplexer according to a sixth embodiment of the present invention. It is a schematic sectional drawing of the optical multiplexer / demultiplexer by the 7th Embodiment of this invention. It is a disassembled perspective view of the optical multiplexer / demultiplexer by the 8th Embodiment of this invention. It is sectional drawing of the optical multiplexer / demultiplexer by 8th Embodiment. It is a perspective view of the prism block used for the optical multiplexer / demultiplexer same as the above. It is the schematic which shows the manufacturing method of the block for multiplexing / demultiplexing. (A) (b) is schematic which shows another manufacturing method of the block for multiplexing / demultiplexing. (A) (b) (c) is the schematic which shows another manufacturing method of the block for multiplexing / demultiplexing. It is the schematic which shows another manufacturing method of the block for multiplexing / demultiplexing. It is the schematic which shows another manufacturing method of the block for multiplexing / demultiplexing. It is the schematic which shows another manufacturing method of the block for multiplexing / demultiplexing. (A) (b) (c) is a perspective view which shows the manufacturing process of the partial mold for prism pattern shaping | molding for shape | molding a prism block. (D) and (e) are perspective views showing a step subsequent to FIG. (A) (b) is a perspective view which shows the manufacturing method of the block for shaping | molding. It is a perspective view of a partial metal mold | die. It is sectional drawing which shows the metal mold | die for shape | molding a prism block. (A) and (b) are perspective views which show the assembly process of the block for multiplexing / demultiplexing. It is a perspective view which shows another shape of a prism block. It is a schematic sectional drawing of the optical multiplexer / demultiplexer by the 9th Embodiment of this invention. (A) is the perspective view from the back surface side of the microlens array used for the optical multiplexer / demultiplexer same as the above, (b) is the perspective view from the surface side of the microlens array. It is action | operation explanatory drawing of the optical multiplexer / demultiplexer by 9th Embodiment. It is a schematic sectional drawing of the optical multiplexer / demultiplexer by the 10th Embodiment of this invention. It is a disassembled perspective view of the optical multiplexer / demultiplexer by the 11th Embodiment of this invention. It is sectional drawing for operation | movement description of an optical multiplexer / demultiplexer same as the above. It is sectional drawing in another cross section for the effect | action description of an optical multiplexer / demultiplexer same as the above. It is a perspective view for operation | movement description of an optical multiplexer / demultiplexer same as the above. It is the schematic which shows the link state of an optical multiplexer / demultiplexer same as the above. (A) (b) is a figure explaining the effect | action by comparing the said link state with a different link state. It is a disassembled perspective view which shows the modification of the 11th Embodiment of this invention. It is a disassembled perspective view which shows another modification of the 11th Embodiment of this invention. (A) is a perspective view from the back surface side of the microlens array used for the optical multiplexer / demultiplexer by the modification of FIG. 54, (b) is a perspective view from the surface side of the microlens array. It is a schematic sectional drawing of the optical multiplexer / demultiplexer by the 12th Embodiment of this invention. It is the schematic which shows the link state of an optical multiplexer / demultiplexer same as the above. It is a schematic sectional drawing which shows the modification of the 12th Embodiment of this invention. It is a schematic sectional drawing which shows another modification of the 12th Embodiment of this invention. It is a schematic sectional drawing of the optical multiplexer / demultiplexer by the 13th Embodiment of this invention. It is a schematic sectional drawing which shows the modification of the 13th Embodiment of this invention. It is a schematic sectional drawing of the optical multiplexer / demultiplexer by the 14th Embodiment of this invention. It is a schematic sectional drawing which shows the modification of the 14th Embodiment of this invention.

Explanation of symbols

9a to 9l optical fiber 10 connector 11 optical fiber array 12a to 12l microlens 13 release film
14 Micro lens array 16 Light guide block 17 Filter layer 17a, 17b, 17c, 17d, 17e Filter 18a, 18b Dummy film 19 Mirror layer 20 Cover member 21 AR coating layer 34 Micro lens array 35a-35f Micro lens 36 For multiplexing / demultiplexing Block 37 Prism block 39a to 39f Prism 59a to 59f Optical fiber 60a, 60c to 60f Micro lens 61 Optical fiber cable 62 Optical fiber cable 63a to 63d Filter 64 Filter 67c to 67f Light emitting element 68c to 68f Light receiving element 70 Light guide plate 71 Optical fiber 72a-72e Diffraction element

Claims (14)

A light reflection surface, a plurality of first wavelength selection elements having different transmission wavelengths arranged in a plane parallel to the light reflection surface, and a transmission wavelength arranged in a plane parallel to the light reflection surface It comprises a plurality of different second wavelength selection elements, guides light while reflecting light between the light reflection surface and each of the first wavelength selection elements, combines light of different wavelengths, and reflects light. A light guide means for guiding light while reflecting light between the surface and each of the second wavelength selection elements and demultiplexing light having different wavelengths;
Transmission means for transmitting light of multiple wavelengths;
A plurality of light input means arranged along an arrangement direction of the first wavelength selection elements such that an optical axis is substantially perpendicular to a plane on which the first wavelength selection elements are arranged;
A plurality of light output means arranged along an arrangement direction of the second wavelength selection elements such that an optical axis is substantially perpendicular to a surface on which the second wavelength selection elements are arranged;
One or a plurality of first deflection elements arranged to face the light input means for bending the optical axis direction of the transmitted light;
One or a plurality of second deflection elements arranged to face the light output means for bending the optical axis direction of the transmitted light;
A set of light of a plurality of wavelengths combined between the light reflecting surface of the light guide means and the first wavelength selection element is guided to the transmission means and coupled to the transmission means, and the transmission means is transmitted. A light branching unit that guides another set of light having a plurality of wavelengths that has been guided between the light reflection surface of the light guide unit and the second wavelength selection element, and
The light input means emits light of each wavelength out of a set of multiple wavelengths through the first deflecting element and obliquely enters the first wavelength selection element of the light guiding means;
The light output means receives light of each wavelength from another set of plural wavelengths of light emitted obliquely from the second wavelength selection element of the light guide means via the second deflection element. An optical multiplexer / demultiplexer characterized by The light branching means is
A filter that multiplexes and demultiplexes the set of light of a plurality of wavelengths transmitted by the transmission means and the other set of light of a plurality of wavelengths sent by the transmission means;
Light transmission of an optical fiber, a core, a prism, a mirror or the like for guiding a set of light of a plurality of wavelengths combined between the light reflection surface of the light guide means and the first wavelength selection element to the transmission means. And a light transmission means such as an optical fiber, a core, a prism, a mirror, etc., for guiding the other set of light of a plurality of wavelengths separated by the filter to the second wavelength selection element of the light guide means The optical multiplexer / demultiplexer according to claim 1, further comprising at least one optical transmission unit. 2. The optical multiplexer / demultiplexer according to claim 1, wherein the transmission means is constituted by an optical fiber, the light input means is constituted by a light emitting element, and the light output means is constituted by a light receiving element. The light guiding means is formed by joining a transparent second substrate having a plurality of the wavelength selection elements arranged on the front surface on a transparent first substrate having the light reflecting surface formed on the back surface. The optical multiplexer / demultiplexer according to claim 1, wherein the optical multiplexer / demultiplexer is provided. The light guide means arranges a plurality of transparent second substrates each having the wavelength selection element formed on each surface on a transparent first substrate having the light reflecting surface formed on the back surface. The optical multiplexer / demultiplexer according to claim 1, wherein the optical multiplexer / demultiplexer is joined. The light guiding means is configured such that each wavelength selecting element is formed between a pair of transparent substrates stacked, and the light reflecting surface is formed on the back surface of the substrate located on the back surface side of the substrate. The optical multiplexer / demultiplexer according to claim 1, wherein the optical multiplexer / demultiplexer is characterized by. 2. The surface of the light guide unit on which the wavelength selection element is formed and the deflection element are opposed to each other, and a spacer is interposed between the light guide unit and the deflection element. An optical multiplexer / demultiplexer as described in 1. The optical multiplexer / demultiplexer according to claim 7, wherein the spacer is formed integrally with the deflection element. The optical multiplexer / demultiplexer according to claim 1, wherein a surface of each wavelength selection element is covered with a protective layer. 2. The optical multiplexer / demultiplexer according to claim 1, wherein the deflecting element is constituted by a lens that is not rotationally symmetric about a central axis thereof. The deflection element is configured by a spherical lens, an aspherical lens, or an anamorphic lens arranged so that a center of a cross section of a transmitted light beam is deviated from an optical axis thereof. The optical multiplexer / demultiplexer described. 2. The optical multiplexer / demultiplexer according to claim 1, wherein the deflecting element includes a prism and a lens. 13. The optical multiplexing / demultiplexing according to claim 12, wherein the prism is formed on one surface of the transparent substrate, and the lens is provided on the other surface of the transparent substrate so as to face the prism. vessel. 13. The optical multiplexer / demultiplexer according to claim 12, wherein the prism is integrally formed on a surface of the light guide means, and the lens is disposed at a position facing the prism.

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