JP2007322859A - Optical multiplexer/demultiplexer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To attain both optical demultiplexing and multiplexing simultaneously while a large size of the equipment is suppressed. <P>SOLUTION: Wavelength multiplexed light from an input common port 101 is made parallel light by a convex lens 103, with a waveguide element 105a totally reflected to be made incident on a wavelength selective element 104a, wherein light beams of a specific wavelength region λ1 pass through the wavelength selective element 104a to be received by an output channel port 102a. Also, among light beams (insertion light) from an input channel port 152a, light beams of the specific wavelength region λ1 pass through the wavelength selective element 104a to be added to the light beams to an output common port 151. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an optical multiplexer / demultiplexer that combines and distributes optical signals, extracts optical signals of a plurality of wavelengths from a single optical transmission line, and inserts optical signals of a plurality of wavelengths into a single optical transmission line. The present invention relates to an optical multiplexing / distribution device that multiplexes them.

  With the development of wavelength multiplexing transmission technology in recent years, attention has been focused on functional devices having a plurality of ports. In particular, an optical multiplexer / demultiplexer that has one common port (common port) and a plurality of input / output ports (channel ports), and that can extract or insert an optical signal of a specific wavelength from each channel port, Various systems and structures have been proposed in order to achieve characteristics such as small size, low cost, and low loss.

  The principal part of an example of the conventional optical multiplexer / demultiplexer is shown in FIG. 7 (refer nonpatent literature 1). In FIG. 7, 701 is a common port, 702a, 702b, 702c, and 702d are channel ports, 703, 703a, 703b, 703c, and 703d are convex lenses (optical coupling elements), 704a, 704b, 704c, and 704d are wavelength selection elements, and 705a , 705b, 705c, and 705d are waveguide elements.

  In this example, the common port 701 and the channel ports 702a to 702d are optical fibers (light emitting / receiving elements), and the end faces of these fibers are used as light emitting / receiving points. The waveguide elements 705a to 705d are total reflection mirrors and are arranged in an array. For example, the waveguide elements 705a to 705d are arranged in a line at equal intervals on a flat resin block (not shown) to form a waveguide element array block.

  The wavelength selection elements 704a to 704d are chips each including a film (dielectric multilayer film) that transmits light in a specific wavelength range and reflects light in other wavelength ranges on a quartz substrate, for example. The wavelength selection elements 704a to 704d configured in this manner are arranged and fixed on a flat block 709 having translucency. The wavelength selection elements 704 a to 704 d are bonded and fixed to the block 709 at the carrier side surface from the surface on which the dielectric multilayer film is formed.

  In this example, the wavelength selecting element 704a transmits a light beam having a specific wavelength band λ1, the wavelength selecting element 704b transmits a light beam having a specific wavelength band λ2, and the wavelength selecting element 704c is a light beam having a specific wavelength band λ3. And the wavelength selecting element 704d transmits light of a specific wavelength band λ4.

  In this example, four waveguide elements are provided on the waveguide element block to form a waveguide element array block. However, the entire waveguide elements 705a to 705d may be used as a single plane mirror. Moreover, although it was set as the structure which used the convex lenses 703 and 703a-703d as an optical coupling element, the structure which arrange | positions a concave mirror three-dimensionally and condenses light may be employ | adopted.

  Next, the operation principle when the optical multiplexer / demultiplexer shown in FIG. 7 is used as an optical demultiplexer will be described. In the optical multiplexer / demultiplexer shown in FIG. 7, the wavelength multiplexed light from the common port 701 is converted into parallel light by the convex lens 703, totally reflected by the waveguide element 705a, and incident on the wavelength selection element wavelength selection element 704a. Of the light incident on the wavelength selection element 704a, a light beam having a specific wavelength band λ1 passes through the wavelength selection element 704a, passes through the filter block 709, and is received by the channel port 702a.

  Of the light incident on the wavelength selection element 704a, the remaining light rays not including the specific wavelength band λ1 are reflected, totally reflected by the waveguide element 705b, and incident on the wavelength selection element 704b. Of the light incident on the wavelength selection element 704b, a light beam having a specific wavelength band λ2 passes through the wavelength selection element 704b, passes through the filter block 709, and is received by the channel port 702b.

  In the same manner, a light beam having a specific wavelength band λ3 out of the light incident on the wavelength selection element 704c is received by the channel port 702c, and a light beam having a specific wavelength band λ4 among the light incident on the wavelength selection element 704d is received. Light is received by the channel port 702d. In this way, a light beam in a specific wavelength region is extracted (demultiplexed) from one optical transmission line.

  Next, the operation principle when the optical multiplexer / demultiplexer shown in FIG. 7 is used as an optical multiplexer will be described. In the optical multiplexer / demultiplexer shown in FIG. 7, light from the channel port 702a is converted into parallel light by the convex lens 703a, passes through the filter block 709, and enters the wavelength selection element 704a. Of the light incident on the wavelength selection element 704a, a light beam having a specific wavelength band λ1 is transmitted through the wavelength selection element 704a, totally reflected by the waveguide element 705a, transmitted through the filter block 709, and sent to the common port 701. Sent.

  The light from the channel port 702b is converted into parallel light by the convex lens 703b, passes through the filter block 709, and enters the wavelength selection element 704b. Of the light incident on the wavelength selection element 704b, a light beam having a specific wavelength band λ2 is transmitted through the wavelength selection element 704b, totally reflected by the waveguide element 705b, and incident on the wavelength selection element 704a. The light beam in the specific wavelength range λ2 incident on the wavelength selection element 704a is totally reflected, sent to the waveguide element 705a, and added to the light beam to the common port 701.

  Similarly, light in a specific wavelength region λ3 of light from the channel port 702c passes through the wavelength selection element 704c, and light in the specific wavelength region λ4 of light from the channel port 702d passes through the wavelength selection element 704d. It is transmitted and added to the light beam to the common port 701. In this way, a light beam in a specific wavelength region is inserted (multiplexed) into one optical transmission line.

  In FIG. 7, an optical multiplexer / demultiplexer is shown as an example of a conventional optical multiplexer / demultiplexer. However, if the film surfaces constituting the wavelength selection elements 704a to 704d are half mirrors, a light beam in a specific wavelength region is combined. It is also possible to use not as an optical multiplexer / demultiplexer for demultiplexing but as an optical multiplexer / demultiplexer for combining and distributing light power.

K. Hadama et.al., "A MUX / DEMUX Module for CWDM with Concave Micromirrors," MOC`03, H32, Tokyo, Japan, Oct. 2003. (MOC`03 Technical Digest, pp.248-251)

  By the way, in the optical multiplexer / demultiplexer mentioned above, the function of both an optical demultiplexer and an optical multiplexer cannot be used simultaneously. Here, in order to realize both the optical demultiplexer and the optical multiplexer at the same time, as shown in FIG. 8, two optical multiplexers / demultiplexers may be connected. However, for example, when the multiplexed light beam (optical signal) is demultiplexed into four optical signals and the four optical signals are combined and output, as shown in FIG. 8, it corresponds to eight channel ports 702. Thus, eight wavelength selection elements 704 are required, and nine waveguide elements 705 are also required, which increases the size of the entire apparatus. This problem becomes more prominent as the number of optical signals to be multiplexed / demultiplexed increases.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to realize both optical demultiplexing and optical multiplexing at the same time in a state in which an increase in size of the apparatus is suppressed. To do.

  An optical multiplexing / distributing device according to the present invention receives input light, distributes at least part of the distributed light from the input light, and combines the input light with at least one insertion light to output output light. In the optical combiner / distributor, an input unit that inputs input light, a beam splitter that transmits part of the light and reflects the remainder, and a light splitter that reflects the input light input from the input unit and enters the beam splitter. One waveguide element, a distribution light output unit that outputs the distribution light reflected by the first waveguide element and transmitted through the beam branching element, an insertion light input unit that inputs the insertion light, and the insertion light input unit Reflecting the input light that has been input and transmitted through the beam splitter and the second waveguide device that reflects the input light reflected from the first waveguide device and reflected from the beam splitter, and reflected from the second waveguide device And at least an output unit for outputting the combined insertion light and input light It is obtain things. According to this optical multiplexing and distribution device, the distribution of the input light and the multiplexing of the inserted light are performed via the same optical branching element.

  In the optical multiplexing / distributing device, the input light is wavelength-multiplexed light, and the light beam splitting element is a wavelength selection element that transmits light in a specific wavelength range and reflects light in other wavelength ranges. Further, in the optical coupling / distributing device, a distribution light coupling element for optically coupling the distribution light transmitted through the light beam branching element to the distribution light output unit, and an insertion for optically coupling the insertion light input from the insertion light input unit to the light beam branching element. You may make it provide an optical coupling element.

  In this case, the first distance between the distribution light coupling element, the insertion light coupling element, and the light beam branching element is 1.5 times the second distance between the light beam branching element, the first waveguide element, and the second waveguide element, or It is good to be 0.5 times. Further, for example, the distribution light coupling element and the insertion light coupling element may be configured by a convex lens. Further, the distribution light coupling element and the insertion light coupling element may be constituted by a concave mirror. Further, the distribution optical coupling element and the insertion optical coupling element may be the same optical coupling element.

  In the optical coupling / distributing device, the first waveguide element and the second waveguide element may be formed of a reflecting mirror. The first waveguide element and the second waveguide element may be integrally formed. Further, the first waveguide element and the second waveguide element may be constituted by a concave mirror.

  As described above, according to the present invention, the input unit for inputting the input light, the beam splitter for transmitting a part of the light and reflecting the remaining light, and the input light input from the input unit for the first waveguide. The distribution light reflected by the element and incident on the light beam branching element and transmitted through the light beam branching element is output from the distribution light output unit, and the insertion light input from the insertion light input unit is incident on the light beam branching element. The input light reflected by the first waveguide element and reflected by the light beam splitting element is reflected by the second waveguide element by the transmitted insertion light, and the insertion light and the input light are combined and output from the output unit. I made it. Thus, according to the present invention, since the distribution of the input light and the multiplexing of the insertion light are performed through the same optical branching element, the optical demultiplexing and An excellent effect is obtained that both optical multiplexing can be realized simultaneously.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a configuration diagram showing a configuration example of an optical multiplexing / distributing device according to an embodiment of the present invention. In FIG. 1, 101 is an input common port, 102a, 102b, 102c, and 102d are output channel ports (distributed light output units), 103 is a convex lens (optical coupling element) for the input common port 101, 103a, 103b, 103c, and 103d. Is a convex lens (distribution optical coupling element) on the output channel port side, 104a, 104b, 104c, and 104d are wavelength selection elements (beam splitting elements), 105a, 105b, 105c, 105d, and 105e are waveguide elements, and 151 is an output common port. , 152a, 152b, 152c, and 152d are input channel ports (inserted light input units), 153 is a convex lens (optical coupling element) for the output common port 151, and 153a, 153b, 153c, and 153d are convex lenses on the input channel port side (inserted) Optical coupling element).

  In the optical combining and distributing apparatus shown in FIG. 1, the input common port 101 and the input channel ports 152a to 152d are optical fibers (light emitting elements), and the end faces of these fibers are used as light emitting points. On the other hand, the output common port 151 and the output channel ports 102a to 102d are optical fibers (light receiving elements), and end faces of these fibers are used as light receiving points. The waveguide elements 105a to 105e are total reflection mirrors and are provided in an array. For example, the waveguide elements 105a to 105e are arranged in a line at equal intervals on a flat resin block (not shown) to form a waveguide element array block.

  The wavelength selection elements 104a to 104d are chips each having a film (dielectric multilayer film) that transmits light in a specific wavelength range (optical signal) and reflects light in other wavelength ranges on a quartz substrate, for example. It is. The wavelength selection elements 104a to 104d configured in this manner are arranged and fixed on a flat block 109 having translucency. The filter block 109 is made of glass, for example. The wavelength selection elements 104 a to 104 d are bonded and fixed to the block 109 on the carrier side surface with respect to the surface on which the dielectric multilayer film is formed.

  The wavelength selection element 104a transmits light in a specific wavelength range λ1, the wavelength selection element 104b transmits light in a specific wavelength range λ2, the wavelength selection element 104c transmits light in a specific wavelength range λ3, The wavelength selection element 104d transmits a light beam having a specific wavelength band λ4.

  Further, although five waveguide elements are provided on the waveguide element block to form a waveguide element array block, the entire waveguide elements 105a to 105e may be used as a single plane mirror. Further, although a convex lens is used as the optical coupling element, a configuration in which a concave mirror is three-dimensionally arranged to collect light may be employed.

  Next, the operation principle of the optical demultiplexing of the optical combining / distributing device shown in FIG. 1 will be described. In the optical multiplexer / demultiplexer shown in FIG. 1, the wavelength multiplexed light from the input common port 101 is converted into parallel light by the convex lens 103, totally reflected by the waveguide element 105a, and incident on the wavelength selection element wavelength selection element 104a. The light is incident from a direction different from the normal direction of the incident / exit surface of the wavelength selection element 104. Of the light incident on the wavelength selection element 104a, a light beam having a specific wavelength band λ1 passes through the wavelength selection element 104a, passes through the filter block 109, and is received by the output channel port 102a. The light beam in the wavelength region λ1 that has passed through the wavelength selection element 104a is collected by the convex lens 103a and optically coupled to the input end of the output channel port 102a.

  Of the light incident on the wavelength selection element 104a, the remaining light rays not including the specific wavelength band λ1 are reflected, totally reflected by the waveguide element 105b, and incident on the wavelength selection element 104b. Of the light incident on the wavelength selection element 104b, a light beam having a specific wavelength band λ2 passes through the wavelength selection element 104b, passes through the filter block 109, and is received by the output channel port 102b. The light beam in the wavelength band λ2 that has passed through the wavelength selection element 104b is collected by the convex lens 103b and optically coupled to the input end of the output channel port 102b.

  In the same manner, a light beam having a specific wavelength band λ3 out of the light incident on the wavelength selection element 104c is received by the output channel port 102c, and a light beam having a specific wavelength band λ4 among the light incident on the wavelength selection element 104d. Is received at the output channel port 102d. In this way, a light beam in a specific wavelength region is extracted (demultiplexed) from one optical transmission line.

  Next, the operation principle of optical multiplexing of the optical multiplexing / distribution device shown in FIG. 1 will be described. In the optical combiner / distributor shown in FIG. 1, light (inserted light) from the input channel port 152d is converted into parallel light by the convex lens 153d, passes through the filter block 109, and enters the wavelength selection element 104d. The light is incident from a direction different from the normal direction of the incident / exit surface of the wavelength selection element 104. The insertion light input from the input channel port 152d is collected by the convex lens 153d and optically coupled to the wavelength selection element 104a. Of the light incident on the wavelength selection element 104d in this way, a light beam having a specific wavelength band λ4 is transmitted through the wavelength selection element 104d, totally reflected by the waveguide element 105e, and sent to the output common port 151. The light totally reflected by the waveguide element 105 e is collected by the convex lens 153 and optically coupled to the input end of the output common port 151.

  The light from the input channel port 152c is converted into parallel light by the convex lens 153c, passes through the filter block 109, and enters (optically couples) the wavelength selection element 104c. Of the light incident on the wavelength selection element 104c, a light beam having a specific wavelength band λ3 is transmitted through the wavelength selection element 104c, totally reflected by the waveguide element 105d, and incident on the wavelength selection element 104d. The light beam in the specific wavelength range λ3 incident on the wavelength selection element 104d is totally reflected, sent to the waveguide element 105e, and added (inserted) to the light beam to the output common port 151.

  In the same manner, the light beam in the specific wavelength band λ2 of the light from the input channel port 152b passes through the wavelength selection element 104b, and the light beam in the specific wavelength band λ1 of the light from the input channel port 152a is the wavelength selection element. The light is transmitted through 104 a and added to the light beam to the output common port 151. In addition, of the wavelength multiplexed light from the input common port 101, the light reflected from all of the wavelength selection elements 104a to 104d is also added (inserted) to the light beam to the output common port 151. In this way, a light beam in a specific wavelength region is inserted (multiplexed) into one optical transmission line.

  As described above, according to the optical multiplexing / distribution apparatus shown in FIG. 1, the four wavelength selection elements can simultaneously perform both the optical demultiplexing and the optical multiplexing of the four channel ports, and the eight wavelength selection elements. Compared to a conventional apparatus that requires a large size, the increase in size is suppressed. In addition, since the output channel port and the input channel port having the same wavelength are arranged adjacent to each other, the light receiving element and the light emitting element (optical fiber) can be easily connected to the transceiver module. If a half mirror or the like is used instead of the wavelength selection element, it is not used as an optical multiplexer / demultiplexer that multiplexes / demultiplexes light beams in a specific wavelength range, but as an optical multiplexer / distributor that combines and distributes the power of light. Is also possible.

  By the way, as specific examples of wavelength selection elements when a specific wavelength range is fixed, a band pass filter using a dielectric multilayer film, an edge filter, and a wavelength-order fine grating structure are periodically formed on the surface. There is a resonance mode filter formed in the above. In addition, the wavelength range to be transmitted can be changed independently for each wavelength selection element by external control. In this case, a wavelength tunable filter using the electro-optic effect or the thermo-optic effect, MEMS (Micro There are etalon filters using Electro Mechanical Systems) technology.

  Next, another optical coupling / distributing device according to the embodiment of the present invention will be described. FIG. 2 is a configuration diagram illustrating a configuration example of the optical coupling / distributing device of the present embodiment. In the optical combining and distributing apparatus shown in FIG. 2, the convex lens 103a on the output channel port side and the convex lens 153a on the input channel port side of the optical combining and distributing apparatus shown in FIG. 1 are the same channel port convex lens (optical coupling element) 203a. Is. Similarly, the optical coupling device shown in FIG. 2 includes channel port convex lenses 203b, 203c, and 203d. Other configurations are the same as those in FIG.

  Next, the operation principle of the optical demultiplexing of the optical combining / distributing device shown in FIG. 2 will be described. In the optical multiplexer / demultiplexer shown in FIG. 2, the wavelength multiplexed light from the input common port 101 is converted into parallel light by the channel port convex lens 203a, is totally reflected by the waveguide element 105a, and is incident on the wavelength selection element wavelength selection element 104a. The Of the light incident on the wavelength selection element 104a, a light beam having a specific wavelength band λ1 passes through the wavelength selection element 104a, passes through the filter block 109, and is received by the output channel port 102a.

  Of the light incident on the wavelength selection element 104a, the remaining light rays not including the specific wavelength band λ1 are reflected, totally reflected by the waveguide element 105b, and incident on the wavelength selection element 104b. Of the light incident on the wavelength selection element 104b, a light beam having a specific wavelength range λ2 passes through the wavelength selection element 104b, passes through the filter block 109, and is collected by the channel port convex lens 203b, and is output at the output channel port 102b. Received light.

  In the same manner, among the light incident on the wavelength selection element 104c, light in a specific wavelength range λ3 is collected by the channel port convex lens 203c, received by the output channel port 102c, and incident on the wavelength selection element 104d. Of the received light, a light beam having a specific wavelength band λ4 is collected by the channel port convex lens 203d and received by the output channel port 102d. In this way, a light beam in a specific wavelength region is extracted (demultiplexed) from one optical transmission line.

  Next, the operation principle of optical multiplexing of the optical multiplexing / distribution device shown in FIG. 2 will be described. 2, the light from the input channel port 152d is converted into parallel light by the channel port convex lens 203d, passes through the filter block 109, and enters the wavelength selection element 104d. Of the light incident on the wavelength selection element 104d, a light beam having a specific wavelength band λ4 is transmitted through the wavelength selection element 104d, totally reflected by the waveguide element 105e, and sent to the output common port 151.

  The light from the input channel port 152c is converted into parallel light by the channel port convex lens 203c, passes through the filter block 109, and enters the wavelength selection element 104c. Of the light incident on the wavelength selection element 104c, a light beam having a specific wavelength band λ3 is transmitted through the wavelength selection element 104c, totally reflected by the waveguide element 105d, and incident on the wavelength selection element 104d. The light beam in the specific wavelength band λ3 incident on the wavelength selection element 104d is totally reflected, sent to the waveguide element 105e, and added to the light beam to the output common port 151.

  Similarly, a light beam having a specific wavelength band λ2 out of the light output from the input channel port 152b and converted into parallel light by the channel port convex lens 203b is transmitted through the wavelength selection element 104b and output from the input channel port 152a. Then, a light beam having a specific wavelength region λ1 out of the parallel light beam by the channel port convex lens 203b is transmitted through the wavelength selection element 104a and added to the light beam to the output common port 151. In addition, among the wavelength multiplexed light from the input common port 101, light reflected from all of the wavelength selection elements 104 a to 104 d is also added to the light beam to the output common port 151. In this way, a light beam having a specific wavelength range is inserted into one optical transmission line.

  As described above, according to the optical combiner / distributor shown in FIG. 2, the optical coupling element for making the light incident on the output channel port and the optical coupling element for making the light emitted from the input channel port into parallel light include , And one optical coupling element per channel port. As a result, according to the optical coupler / distributor shown in FIG. 2, the number of parts can be reduced and the price can be reduced as compared with the optical coupler / distributor shown in FIG. Also, the device can be made smaller.

  Next, another optical coupling / distributing device according to the embodiment of the present invention will be described. 3 and 4 are configuration diagrams illustrating a configuration example of the optical multiplexing and distribution device according to the present embodiment. First, the optical multiplexing / distribution apparatus shown in FIG. 3 has the waveguide elements 105a, 105b, 105d, 104b, 104c, 104d and the intervals (distances) between the waveguide elements 105a, 105b, 105c, 105d, 105e. The distance between 105c, 105d, 105e and the convex lenses 103, 103a, 103b, 103c, 103d, 153, 153a, 153b, 153c, 153d is 1.5 times. By doing so, even at the narrowest distance between adjacent channel ports, the distance between the wavelength selection elements becomes half, and there is no very narrow area.

  In addition, the optical multiplexing / distribution apparatus shown in FIG. 4 has waveguide elements 105a, 105b, 105d, 104b, 104c, 104d and waveguide elements 105a, 105b, 105c, 105d, 105e with respect to the distance (distance). The distance between 105c, 105d, 105e and the convex lenses 103, 103a, 103b, 103c, 103d, 153, 153a, 153b, 153c, 153d is 0.5 times. By doing so, the interval between the channel ports becomes half of the interval between the wavelength selection elements, and there is no very narrow portion.

  Next, another optical coupling / distributing device according to the embodiment of the present invention will be described. FIG. 5 is a configuration diagram illustrating a configuration example of the optical coupling / distributing device of the present embodiment. In FIG. 5, 503 is a concave mirror (optical coupling element) for the input common port 101, 503a, 503b, 503c, and 503d are concave mirrors (optical coupling elements) on the output channel port side, and 553 is a concave mirror (optical coupling) for the output common port 151. (Coupling elements) 553a, 553b, 553c, and 553d are concave mirrors (optical coupling elements) on the input channel port side, and 505 is a reflector. The reflection plate 505 is formed by integrating the waveguide elements 105a, 105b, 105c, 105d, and 105e shown in FIG. Others are the same as in FIG.

  Next, the operation principle of the optical demultiplexing of the optical combining / distributing device shown in FIG. 5 will be described. In the optical multiplexing / distribution device shown in FIG. 5, the wavelength multiplexed light from the input common port 101 is reflected by the concave mirror 503, the traveling direction is changed, is totally reflected by the reflector 505, and is incident on the wavelength selection element wavelength selection element 104a. The For example, as shown in FIG. 5B, the wavelength multiplexed light from the input common port 101 is reflected by the concave mirror 503 to become parallel light, and the wavelength disposed on the input common port 101 side with respect to the concave mirror 503. The traveling direction is changed toward the selection element 104a and the reflection plate 505. Similarly, of the light incident on the wavelength selection element 104a, a light beam having a specific wavelength band λ1 is transmitted through the wavelength selection element 104a, transmitted through the filter block 109, reflected from the concave mirror 503a, and the traveling direction is changed. Further, the light is condensed and incident on the output channel port 102a.

  Of the light incident on the wavelength selection element 104a, the remaining light rays not including the specific wavelength band λ1 are reflected, totally reflected by the reflection plate 505, and incident on the wavelength selection element 104b. Of the light incident on the wavelength selection element 104b, a light beam having a specific wavelength band λ2 is transmitted through the wavelength selection element 104b, is transmitted through the filter block 109, is reflected by the concave mirror 503b, and the traveling direction is changed. 102b.

  In the same manner, the light in the specific wavelength range λ3 out of the light incident on the wavelength selection element 104c is reflected by the concave mirror 503c, changed in the traveling direction, and incident on the output channel port 102c, and enters the wavelength selection element 104d. Of the incident light, a light beam having a specific wavelength range λ4 is reflected by the concave mirror 503d, the traveling direction thereof is changed, and the light beam enters the output channel port 102d. In this way, a light beam in a specific wavelength region is extracted (demultiplexed) from one optical transmission line.

  Next, the operation principle of optical multiplexing of the optical multiplexing / distribution device shown in FIG. 5 will be described. In the optical combining and distributing apparatus shown in FIG. 5, the light from the input channel port 152d is reflected by the concave mirror 553d, the traveling direction is changed, passes through the filter block 109, and enters the wavelength selection element 104d. Of the light incident on the wavelength selection element 104d, a light beam having a specific wavelength band λ4 is transmitted through the wavelength selection element 104d, totally reflected by the reflection plate 505, and sent to the output common port 151.

  The light from the input channel port 152c is reflected by the concave mirror 553c to change the traveling direction, passes through the filter block 109, and enters the wavelength selection element 104c. Of the light incident on the wavelength selection element 104c, a light beam having a specific wavelength band λ3 is transmitted through the wavelength selection element 104c, totally reflected by the reflection plate 505, and incident on the wavelength selection element 104d. The light beam in the specific wavelength band λ3 incident on the wavelength selection element 104d is totally reflected, sent to the reflection plate 505, and added to the light beam to the output common port 151.

  Similarly, a light beam having a specific wavelength band λ2 of light from the input channel port 152b is reflected by the concave mirror 553b and then transmitted through the wavelength selection element 104b, and a specific wavelength of light from the input channel port 152a. The light beam in the region λ1 is reflected by the concave mirror 553a and then transmitted through the wavelength selection element 104a, and is added to the light beam to the output common port 151. In addition, among the wavelength multiplexed light from the input common port 101, light reflected from all of the wavelength selection elements 104 a to 104 d is also added to the light beam to the output common port 151. In this way, a light beam having a specific wavelength range is inserted into one optical transmission line.

  As described above, according to the optical multiplexing / distributing device shown in FIG. 5, the four wavelength selection elements can simultaneously perform both the optical demultiplexing and the optical multiplexing of the four channel ports, and the eight wavelength selection elements. Compared to the conventional apparatus that requires the above, it is possible to further reduce the size. Further, according to the optical coupling / distributing device shown in FIG. 5, the use of a concave mirror as the optical coupling element improves the degree of freedom in designing the optical system, such as arranging the wavelength selection element, the light emitting element, and the light receiving element on the same side. To do. As a result, for example, the positioning mechanism (block 109) of the plurality of wavelength selection elements and the plurality of optical coupling elements can be easily formed integrally, and a structure in which relative positional deviation hardly occurs can be realized.

  Note that coma aberration increases and loss increases as the incident angle increases when light enters the concave mirror. For this reason, it is desirable that the incident angle be as small as possible. On the other hand, if the incident angle is too small, the reflected light interferes with the incident light and desired characteristics cannot be obtained. For these reasons, the incident angle of the light beam on the concave mirror is a problem whether it is too small or too large, and it is better to design it at an appropriate angle. In order to reduce the loss to a practical range by using a normal spherical mirror for the coupling mirror and reduce the size of the optical system, the above incident angle should be at least within 45 °, based on the results of previous studies. It is desirable to hold down.

  Next, another optical coupling / distributing device according to the embodiment of the present invention will be described. FIG. 6 is a configuration diagram illustrating a configuration example of the optical multiplexing and distribution device according to the present embodiment. In FIG. 6, reference numerals 605a, 605b, 605c, 605d, and 605e denote waveguide elements configured from concave mirrors, and the others are the same as those in FIG. According to the optical multiplexing / distributing device shown in FIG. 6 configured as described above, the light (optical signal) that propagates and reflects from the waveguide elements 605a, 605b, 605c, 605d, and 605e can be collected. Signal diffusion can be suppressed.

  For example, when the number of channel ports is provided, when the incident angle of the optical signal to the wavelength selection element is made smaller, and when the arrangement interval of the wavelength selection elements is made wider, the coupling of the input port to the output port is performed. The optical path length to the element becomes long. When the optical path length is thus increased, the propagating optical signal may be diffused and desired characteristics may not be obtained. On the other hand, according to the optical multiplexing / distribution device shown in FIG. 6, since the diffusion of the optical signal can be suppressed, the optical path length can be increased, and the optical signal can be incident on the wavelength selection element having more channel ports. The degree of freedom in design is improved, for example, the angle can be made smaller and the arrangement interval of the wavelength selection elements can be made wider.

It is a block diagram which shows the structural example of the optical coupling / distribution apparatus which concerns on embodiment of this invention. It is a block diagram which shows the structural example of the other optical coupling device which concerns on embodiment of this invention. It is a block diagram which shows the structural example of the other optical coupling device which concerns on embodiment of this invention. It is a block diagram which shows the structural example of the other optical coupling device which concerns on embodiment of this invention. It is a block diagram which shows the structural example of the other optical coupling device which concerns on embodiment of this invention. It is a block diagram which shows the structural example of the other optical coupling device which concerns on embodiment of this invention. It is a block diagram which shows the structural example of the conventional optical combining / splitting device. It is a block diagram which shows the structural example of an optical combining and distributing apparatus.

Explanation of symbols

  101 ... Input common port, 102a, 102b, 102c, 102d ... Output channel port (distributed light output unit), 103 ... Convex lens (optical coupling element), 103a, 103b, 103c, 103d ... Convex lens (distributed optical coupling element), 104a , 104b, 104c, 104d... Wavelength selection elements (light beam splitting elements), 105a, 105b, 105c, 105d... Waveguide elements, 152a, 152b, 152c, 152d ... input channel ports (inserted light input units), 153a, 153b, 153c, 153d ... convex lenses (insertion optical coupling elements).

Claims (10)

In an optical combining / distributing device that inputs input light, distributes at least part of the distribution light from the input light, and outputs at least one insertion light to the input light to output output light,
An input unit for inputting the input light;
A beam splitter that transmits some light and reflects the rest,
A first waveguide element that reflects the input light input from the input unit and causes the input light to enter the beam splitter;
A distribution light output unit that outputs the distribution light reflected from the first waveguide element and transmitted through the light beam branching element;
An insertion light input section for inputting the insertion light;
A second waveguide element that reflects the input light that is input from the insertion light input unit and is transmitted through the light beam branching element and the input light that is reflected from the first waveguide element and reflected from the light beam branching element;
An optical combining / distributing device comprising at least an output unit that reflects the second waveguide element and outputs the combined insertion light and the input light. The optical coupling / distribution device according to claim 1.
The input light is wavelength multiplexed light,
The light beam splitting device is a wavelength selection device that transmits light in a specific wavelength range and reflects light in other wavelength ranges. The optical coupling / distributing device according to claim 1 or 2,
A distribution light coupling element for optically coupling the distribution light transmitted through the light beam branching element to the distribution light output unit;
An optical coupling / distributing device comprising: an insertion light coupling element that optically couples the insertion light input from the insertion light input unit to the light beam branching element. The optical coupling / distributing device according to claim 3.
The first distance between the distribution light coupling element and the insertion light coupling element and the beam branching element is:
The optical coupling / dividing device, wherein the second distance between the light beam branching element, the first waveguide element, and the second waveguide element is 1.5 times or 0.5 times. The optical combining / distributing device according to claim 3 or 4,
The distribution light coupling element and the insertion light coupling element are each composed of a convex lens. The optical combining / distributing device according to claim 3 or 4,
The distribution light coupling element and the insertion light coupling element are each composed of a concave mirror. The optical coupling / distributing device according to any one of claims 3 to 6,
The distribution optical coupling device and the insertion optical coupling device are the same optical coupling device. In the optical combining and distributing device according to any one of claims 1 to 7,
The optical waveguide distribution device, wherein the first waveguide element and the second waveguide element are configured by reflecting mirrors. The optical coupling / distributing device according to claim 8,
The optical waveguide distribution device, wherein the first waveguide element and the second waveguide element are integrally formed. The optical coupling device according to claim 8,
The first waveguide element and the second waveguide element are configured by concave mirrors.

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