PMT ferrule, PMT optical connector, photoelectric circuit board, production jig for PMT optical connector, and production method for PMT optical connector
Patent Information
- Application Number
- PCT/JP2026/010285
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2025-03-28
- Filing Date
- 2026-03-17
- Publication Date
- 2026-10-01
Smart Images
Figure JP2026010285_01102026_PF_FP_ABST
Abstract
Description
PMT ferrule, PMT optical connector, photoelectric circuit board, manufacturing jig for PMT optical connector, method for manufacturing PMT optical connector
[0001] The present invention relates to a PMT ferrule (MT ferrule for polymer waveguides), a PMT optical connector (polymer waveguide MT optical connector), a jig for manufacturing a PMT optical connector, and a method for manufacturing a PMT optical connector.
[0002] Patent Document 1 (Japanese Unexamined Patent Application Publication No. 2018-124381) discloses an optical waveguide structure in which core positions are controlled with high accuracy.
[0003] The waveguide structure described in Patent Document 1 is a waveguide structure used for optical connection components, and includes: a clad having a first end and a second end spaced apart from the first end in a first direction; a plurality of cores extending in the first direction and provided in the clad so as to be spaced apart from each other in a second direction intersecting the first direction; and a partition wall provided in the clad, wherein first optical coupling ends of the respective plurality of cores are exposed at the first end, second optical coupling ends of the respective cores are exposed at the second end, and the partition wall is provided between a first core and a second core that are adjacent to each other among the plurality of cores so as to extend in the first direction.
[0004] In addition, Patent Document 2 (Japanese Unexamined Patent Application Publication No. 2018-87843) discloses an optical wiring component capable of achieving stable optical coupling efficiency with other optical components, a connection method for an optical wiring component that enables the optical wiring component to be connected to other optical components with stable optical coupling efficiency, and a highly reliable electronic device provided with the optical wiring component. The optical wiring component described in Patent Document 2 includes: a sheet-shaped optical waveguide having a first main surface and a second main surface in a front-back relationship with each other, and a light incident / emission surface formed by a part of an outer surface connecting the first main surface and the second main surface; an optical connector having a first outer surface and a second outer surface facing each other, and a through hole or groove penetrating the first outer surface and the second outer surface, the inner surface of which includes a mounting surface on which at least one of the first main surface and the second main surface of the optical waveguide is mounted; and a material having light transmittance and elasticity, provided to cover the light incident / emission surface, and having a pressure of 2 N / mm ２ when pressed at normal temperature, and the elastic body has a compressive deformation amount of 0.005 mm or more when pressed.
[0005] Furthermore, Patent Document 3 (Japanese Patent Application Publication No. 2018-151416) discloses an optical connector that allows for easy replacement of a portion having a spot size conversion function. The optical connector described in Patent Document 3 comprises an optical fiber, a ferrule having an optical fiber holding hole into which the optical fiber is inserted and held, and an optical end face into which the core of the optical fiber is exposed, a stub attached to the optical end face of the ferrule, and a guide pin for fixing the relative positions of the ferrule and the stub. At least one of the ferrule and the stub has a guide hole into which the guide pin is inserted, and the stub has a waveguide that optically couples with the optical fiber, a first end face into which the core of the waveguide is exposed, and a second end face opposite the first end face and facing the optical end face. The mode field shape of the waveguide is circular, the mode field diameter of the waveguide at the first end face is smaller than the mode field diameter of the waveguide at the second end face, and the mode field diameter of the waveguide at the second end face is approximately the same as the mode field diameter of the optical fiber.
[0006] Furthermore, Patent Document 4 (Japanese Patent Application Publication No. 2016-177011) discloses an optical wiring component capable of achieving stable optical coupling efficiency with optical components, an optical wiring component with an end face protection member, a method for manufacturing an optical wiring component with an end face protection member that can efficiently manufacture the optical wiring component with an end face protection member, and a highly reliable electronic device equipped with an optical wiring component. The optical wiring component of Patent Document 4 comprises an optical waveguide having a long core portion and an optical input / output surface that can be optically coupled to the core portion; an optical connector having a connector body, an opposing surface provided on the connector body that faces other optical components that are optically coupled to the optical waveguide, a non-opposing surface provided on the connector body that is on the opposite side of the opposing surface, and a mounting surface on which the optical waveguide is placed; and an adhesive film that is in contact with the opposing surface and is provided in a position facing the optical input / output surface and has adhesive properties.
[0007] Furthermore, Patent Document 5 (Japanese Patent Application Publication No. 2016-18165) discloses an optical wiring component capable of precisely positioning the end faces of each optical waveguide, an optical waveguide assembly, and a method for manufacturing an optical wiring component capable of precisely positioning each optical waveguide relative to each other. The optical wiring component described in Patent Document 5 has a plurality of optical waveguides in the shape of a sheet, and fixing parts provided between each optical waveguide when the optical waveguides are stacked in the thickness direction, fixing the vicinity of one end of each optical waveguide together, wherein the fixing parts are offset to the other end side from the end face of one end of each optical waveguide.
[0008] Furthermore, Patent Document 6 (Japanese Patent Application Publication No. 2014-85418) discloses a ferrule and optical waveguide assembly that are easy to manufacture and suitable for mass production. The ferrule described in Patent Document 6 is a ferrule used to be attached to the tip of an optical waveguide having an overall elongated shape, and having a tip opening that opens at the tip and a base opening that opens at the base, and comprising a ferrule body having a lumen into which the tip of the optical waveguide is inserted, and a tip member provided to close the tip opening, having light transmittance, and having a contact portion into which the tip surface of the optical waveguide abuts.
[0009] Furthermore, Patent Document 7 (Japanese Patent Application Publication No. 2018-097012) discloses a spot size converter that couples optical waveguides of different sizes with high efficiency and low loss, and has high resistance to misalignment and design flexibility. The spot size converter described in Patent Document 7 is a spot size converter that converts the beam diameter between optical wirings of different core sizes, and comprises a first surface optically connected to a first optical wiring of a first size, a second surface optically connected to a second optical wiring of a second size that is larger than the first size, and a tapered polymer waveguide whose diameter decreases conically from the first surface to the second surface.
[0010] Furthermore, Patent Document 8 (Japanese Patent Application Publication No. 2020-134552) discloses an optical waveguide device that generates pulsed light stably and efficiently with good reproducibility and mode synchronization. The optical waveguide device described in Patent Document 8 has a cladding layer formed of a first monomer containing a predetermined amount of nanocarbon material and a dispersion stabilizer for the nanocarbon material, and a waveguide core formed of a second monomer different from the first monomer.
[0011] Furthermore, Patent Document 9 (Japanese Patent No. 6038787) discloses an optical waveguide and a method for manufacturing the same, which offers a high degree of freedom in the layout design of the core portion and can be manufactured by a simple method. The optical waveguide described in Patent Document 9 is an optical waveguide formed on a substrate, and has a core portion through which light propagates and a cladding portion that covers the periphery of the core portion, and the cladding portion is integrally formed without creating an interface inside the cladding portion.
[0012] Japanese Patent Publication No. 2018-124381, Japanese Patent Publication No. 2018-87843, Japanese Patent Publication No. 2018-151416, Japanese Patent Publication No. 2016-177011, Japanese Patent Publication No. 2016-18165, Japanese Patent Publication No. 2014-85418, Japanese Patent Publication No. 2018-097012, Japanese Patent Publication No. 2020-134552, Japanese Patent No. 6038787
[0013] Patent Document 1 improves accuracy by placing a core between isolation walls, and Patent Document 2 achieves stable optical coupling using a special elastic material. Furthermore, Patent Document 3 discloses a technology that allows for easy replacement of the spot size conversion function part, addressing concerns about the deterioration of the optical performance of the spot size converter after long-term use. Patent Document 4 enables stable optical coupling efficiency by providing an adhesive film that contacts the opposing surface and is positioned opposite the light input and output surfaces. Patent Document 5 discloses that the end faces of each optical waveguide can be precisely positioned by shifting them toward the other end side of one end of each optical waveguide. Patent Document 6 describes a tip member provided to close the tip opening of the ferrule body, and this tip member has a contact portion that abuts against the tip surface of the optical waveguide. By having this contact portion abut against the tip surface of the optical waveguide, when fixing the ferrule body and the optical waveguide with adhesive, the adhesive is prevented from flowing and adhering to the tip surface of the optical waveguide, thereby eliminating the need for polishing.
[0014] Patent Document 7 discloses the realization of a polymer optical waveguide type SSC with a frustoconical or three-dimensional tapered shape in which the radial size changes symmetrically with respect to the optical axis. Patent Document 8 discloses a technique to solve the problem that when CNT aggregates are present on the trajectory of the needle, the core meanders as the needle scans to avoid the CNT aggregates, as shown in Figure 1. This causes excessive loss in the meandering channel and makes mode synchronization difficult. Furthermore, Patent Document 9 discloses a technique to simplify the manufacturing process and allow the core to be freely and continuously formed in the X, Y, and Z directions, thereby increasing the degree of freedom in the layout design of the core.
[0015] However, in recent years, there has been a growing need for higher density and greater complexity in fiber optic cables or optical wiring.
[0016] An object of the present invention is to provide a PMT ferrule and PMT optical connector that can connect optical waveguides with high efficiency, a jig for manufacturing the PMT optical connector, and a manufacturing method. Another object of the present invention is to provide a PMT ferrule and PMT optical connector that can connect optical waveguides with high efficiency and facilitate positioning, a jig for manufacturing the PMT optical connector, and a manufacturing method.
[0017] (1) A PMT optical connector according to the first aspect comprises a mosquito waveguide and a PMT ferrule, wherein the PMT ferrule has a recess on its top surface, the inner bottom surface and both inner sides of the recess are formed as planes, the mosquito waveguide is arranged to extend from the other end of the recess toward the one end, and the top surface of the mosquito waveguide is coplanar with the top surface of the PMT ferrule.
[0018] In recent years, there has been a growing demand to mount large-scale integrated circuits and optical conversion modules on the same substrate. In particular, there is a need for shorter electrical transmission lines, low loss, wide bandwidth, and reduced noise, thus lowering power consumption. Especially as optical wiring becomes denser and more complex, research is being conducted to address this by incorporating polymer optical waveguides (POWs) into the substrate. As a result, it is expected that next-generation CPOs will introduce optical interconnects even between IC chips on the board. Furthermore, there is a possibility that the entire configuration, with operators in electrical circuits and input / output in optical integrated circuits, will ultimately be optical. Therefore, miniaturization of photoelectric conversion modules is necessary to replace electrical wiring with optical wiring. Silicon photonics chips (SiPh) are attracting attention as a key device for this. However, connecting current SiPh chips with SMFs results in large coupling losses due to differences in waveguide beam diameter (spot size) and Ch pitch. Therefore, the use of polymer optical waveguides, which offer a high degree of design flexibility, is anticipated.
[0019] In this case, the PMT ferrule is a ferrule for a PMT optical connector formed by the mosquito method, in which the inner bottom surface and both inner sides of the recess are formed as planes, and the top surface of the mosquito waveguide is formed to be on the same plane as the top surface of the PMT ferrule. Therefore, the mosquito waveguide can be continuously formed on the inner bottom surface and both inner sides of the recess of the ferrule. In this way, an optical waveguide integrated with a multi-core ferrule can be continuously, easily, and reliably formed using the mosquito method, thus minimizing coupling loss. As a result, a PMT optical connector that can connect optical waveguides with high efficiency can be obtained.
[0020] (2) The PMT optical connector relating to the second aspect is a PMT optical connector relating to the first aspect, wherein the PMT ferrule has a pair of guide holes on the outside of both inner sides of the recess, the guide holes are formed in a cylindrical shape from one end to the other of the PMT ferrule, and the surface S connecting the central axes of the pair of guide holes may be provided 10 μm to 100 μm on the top side of the inner bottom surface of the recess.
[0021] In this case, since a hole for a guide pin is provided on one end face of the recess, it is possible to connect to an MT ferrule or electrical circuit board with high positional accuracy, and coupling loss can be minimized. Also, since the inner bottom surface of the recess is positioned lower than the surface S on the central axis of the guide hole, the core of the mosquito waveguide can be arranged along the central axis of the guide hole. Furthermore, since the inner bottom surface of the recess is positioned lower by a predetermined distance from the surface (surface S) on which the core of the mosquito waveguide is arranged, a frictional force acts from the inner bottom surface on the cladding polymer near the core polymer. Therefore, when drawing multiple core polymers using the mosquito method, the generation of vortices or oscillations can be suppressed, and a highly accurate mosquito waveguide can be formed.
[0022] (3) A PMT optical connector relating to the third aspect is a PMT optical connector according to the first or second, wherein the mosquito waveguide has a cladding polymer and a plurality of core polymers, and the plurality of core polymers may be provided on the same plane as the plane S connecting the central axes of a pair of guide holes.
[0023] This allows for more precise alignment with the connection destination using a pair of guide pins, resulting in a PMT optical connector with lower connection loss. Furthermore, it is compatible with MT ferrules to which multi-core optical fibers are connected.
[0024] (4) A PMT optical connector relating to the fourth aspect is a PMT optical connector according to any one of the first to third, wherein the mosquito waveguide has a cladding polymer and a plurality of core polymers, and the core polymer may have a gradually changing core diameter and / or core pitch in the extending direction.
[0025] In the mosquito method, the core is drawn using a dispenser, allowing the core size to be gradually changed by adjusting the amount of core polymer coating, and the core arrangement to be gradually changed by controlling the movement of the dispenser. Therefore, by gradually changing the core diameter of the mosquito waveguide in the direction of extension, a PMT optical connector with the function of a spot size converter for connecting optical signals with different core diameters can be created. Furthermore, by gradually changing the core pitch of the mosquito waveguide in the direction of extension, a PMT optical connector with the function of a pitch change adapter for connecting optical connectors with different core pitches can be created. In this way, since PMT optical connectors with different core diameters and / or core pitches can be created at one end and the other end of the mosquito waveguide, optical connections between different standards, such as connecting an electrical circuit board and an optical fiber for long-distance communication, can be easily facilitated.
[0026] (5) The photoelectric circuit board according to the fifth aspect comprises an electrical circuit board equipped with a photoelectric element and one of the first to fourth PMT optical connectors, wherein an optical waveguide extending from the photoelectric element and a mosquito waveguide of the PMT optical connector are optically connected.
[0027] This allows for easy optical connection between an electrical circuit board and an optical fiber for long-distance communication.
[0028] (6) A PMT ferrule according to the sixth aspect is a PMT ferrule having a recess provided on the top surface, a pair of guide holes provided on both outer sides of the recess, and a flange portion on the other end that protrudes in the direction of both inner sides, wherein the recess is formed extending from one end to the other, the inner bottom surface and both inner sides of the recess are formed as flat surfaces, the top surface is formed as a flat surface from one end to the other, the mosquito waveguide is arranged to extend from the other end of the recess of the ferrule body to the one end, and the plane S connecting the central axes of the pair of guide holes is provided 10 μm to 100 μm on the top surface side of the inner bottom surface of the recess.
[0029] In this case, the PMT ferrule is a ferrule for a PMT optical connector formed by the mosquito method, in which a recess is formed extending from one end to the other for a predetermined length, and the inner bottom surface and both inner sides of the recess are formed as planes, so that a mosquito waveguide can be continuously formed on the inner bottom surface and both inner sides of the recess of the ferrule. In particular, an optical waveguide integrated with a multi-core ferrule can be continuously, easily, and reliably formed using the mosquito method, so coupling loss can be minimized. As a result, a ferrule for a PMT optical connector that can connect mosquito waveguides with high efficiency can be obtained. Furthermore, since the inner bottom surface of the recess is positioned at a predetermined distance lower than the surface (surface S) on which the cores of the mosquito waveguide are arranged, a frictional force acts from the inner bottom surface on the cladding polymer near the core polymer. Therefore, when drawing multiple core polymers by the mosquito method, the generation of vortices or oscillations can be preferably suppressed, so that a highly accurate mosquito waveguide can be formed.
[0030] (7) A jig according to the seventh aspect is a jig for manufacturing a PMT optical connector by the mosquito method, and includes a hole for fitting a PMT ferrule, a flush recess that is flush with the inner bottom surface and inner side surfaces of the recess of the PMT ferrule when the PMT ferrule is fitted into the hole, and a run-up recess for running the dispenser.
[0031] In this case, since a predetermined length of run-up groove is provided for the dispenser to gain momentum, the multi-axis robot can reliably perform stable movement in the run-up groove, and the core polymer can be drawn stably and linearly. In other words, the formation of a mosquito waveguide can be performed with high precision.
[0032] (8) The jig relating to the eighth aspect is a jig relating to the other aspects of the seventh aspect, wherein the flush recessed path is composed of a first jig that communicates flush with one inner side surface of the recess, a second jig that communicates flush with one inner side surface of the recess and is provided opposite to the first jig, and a third jig that communicates flush with the inner bottom surface, and the first jig and the second jig may each be formed to be separable from the third jig.
[0033] In this case, a part of the jig that forms the mosquito waveguide can be separated. As a result, a stable mosquito waveguide can be easily formed without damaging the mosquito waveguide.
[0034] (9) The jig relating to the ninth aspect may be a jig relating to the seventh or eighth aspect, in which the approach recess is composed of a fourth jig that forms a hole and communicates flush with one inner side surface of the recess, a fifth jig provided opposite the fourth jig that forms a hole and communicates flush with the other inner side surface of the recess, and a sixth jig that forms a hole and communicates flush with the inner bottom surface of the recess.
[0035] In this case, a portion of the jig that forms the mosquito waveguide in the pre-indentation recess can be separated. As a result, a highly accurate mosquito waveguide can be easily manufactured by polishing or removing the mosquito waveguide corresponding to the pre-indentation recess afterward, without damaging the optical waveguide in the pre-indentation recess.
[0036] (10) In the jig relating to the tenth phase, the jig relating to any of the seventh to ninth phases may have a fourth jig, a fifth jig, and a sixth jig provided on both ends of the first jig, the second jig, and the third jig, respectively.
[0037] In this case, the ends of the jig that forms the mosquito waveguide can be separated. As a result, a mosquito waveguide with PMT optical connector ferrules formed at both ends can be easily manufactured.
[0038] (11) A method for manufacturing a PMT optical connector according to the 11th aspect includes: a fitting step of fitting one or more PMT ferrules into a jig; a coating step of applying uncured cladding UV curing resin to the preparatory recess and flush recess of the jig; a waveguide forming step of dispensing core UV curing resin using a dispenser from one preparatory recess through the flush recess to the other preparatory recess to form a mosquito waveguide; a UV irradiation step of irradiating the mosquito waveguide obtained in the waveguide forming step with ultraviolet light; a step of removing the jig after the UV irradiation step; and a removal step of removing the optical waveguide formed in the preparatory recess after the step of removing the jig.
[0039] In this case, during the waveguide formation process, the UV-curing resin for the core (core polymer before curing) can be continuously drawn in one step by the dispenser from the preparatory recess on one end of the jig to the flush recess, and then to the preparatory recess on the other end, thus enabling the formation of the mosquito waveguide core with high precision. By performing this waveguide formation process multiple times, a multi-core PMT connector can be obtained. Furthermore, by cutting and removing the mosquito waveguides corresponding to the preparatory recesses on one end and the other end at the end, the mosquito waveguides necessary for optical communication can be formed with high precision, thereby minimizing coupling loss. As a result, a PMT optical connector that can connect optical signals with high efficiency can be obtained.
[0040] This is a schematic perspective view showing an example of a PMT optical connector in this embodiment. This is a schematic explanatory diagram of the connection end face of a PMT optical connector in this embodiment. This is a schematic perspective view showing a PMT ferrule in this embodiment. This is a schematic perspective view showing a PMT ferrule in this embodiment. This is a schematic perspective view showing an example of a jig for manufacturing a PMT optical connector. This is a schematic perspective view showing an example of the relationship between a pair of waveguide forming plates and a waveguide forming bottom plate. This is a schematic perspective view showing an example of the relationship between a pair of retaining plates and a retaining plate and a bottom plate. This is a diagram showing an example of the manufacturing process for a PMT optical connector in this embodiment. This is a schematic perspective view showing an example of the manufacturing process for a PMT optical connector. This is a schematic perspective view showing an example of the manufacturing process for a PMT optical connector. This is a schematic perspective view showing an example of the manufacturing process for a PMT optical connector. This is a schematic perspective view showing an example of the manufacturing process for a PMT optical connector. This is a schematic perspective view showing an example of the manufacturing process for a PMT optical connector. This is a schematic perspective view showing an example of the manufacturing process for a PMT optical connector. This is a schematic perspective view showing a modified PMT ferrule. This is a photograph showing an example of a PMT optical connector in this embodiment.
[0041] The embodiments of the present invention will be described below with reference to the drawings. While multiple embodiments of the present invention are shown, each embodiment may be implemented independently or in combination of one or more embodiments. In the following description, identical parts are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed descriptions of them will not be repeated.
[0042] [This Embodiment] (PMT Optical Connector 100) Figure 1 is a schematic perspective view showing an example of a PMT optical connector 100 in this embodiment. The PMT optical connector 100 in this embodiment is capable of terminating a flexible polymer optical waveguide (mosquito waveguide) and connecting to an MT-type ferrule. It goes without saying that the PMT optical connector 100 can be connected to other optical waveguides, and that PMT optical connectors 100 can also be connected to each other. Furthermore, the PMT optical connector 100 may be connected to other optical fibers using a collimating lens. As a result, parallel light is produced, enabling a stable connection and long-distance communication. The core of the mosquito waveguide uses a resin with a lower refractive index than the cladding, confining the communication light within the core to enable optical communication. By adjusting the size of the core, multimode light or single-mode light may be transmitted. Furthermore, while this embodiment shows an example where PMT ferrules 200 are provided at both ends of the mosquito waveguide 300, the embodiment is not limited to this, and PMT ferrules 200 may be provided at only one end.
[0043] In recent years, the demand for optical wiring (CPO) within data centers has been increasing. Therefore, silicon photonics (SiPh) technology is expected to be utilized to expand the optical wiring domain. Conventional optical fiber wiring presents difficulties in complex wiring, and direct connection of optical fibers results in significant losses; therefore, the use of optical waveguides (POW) is being considered. Optical waveguides for IC chips are also being explored, and while PMT connectors are currently used for connection to external MT ferrules, research and development into highly efficient connection methods is still underway at various companies.
[0044] As shown in Fig. 1, the PMT optical connector 100 includes a pair of PMT ferrules 200 and a Mosquito waveguide 300. Fig. 2 is a partially enlarged view of the vicinity of the connection end face of the PMT optical connector 100. The concave portion (concave shape) of the PMT ferrule 200 is filled with the Mosquito waveguide 300, and the top surface and upper surface of both are formed to be coplanar. The Mosquito waveguide 300 includes a clad polymer 301 extending in a quadrangular prism shape from one end side to the other end side, and a plurality of core polymers 302 extending in a columnar shape within the clad polymer.
[0045] The plurality of core polymers 302 shown in Fig. 2 are aligned at a predetermined pitch on the same plane as a plane S connecting the central axes of a pair of guide pin holes 290, and it is preferable that the central axis of each core polymer 302 is located on the plane S. Accordingly, even when a pressing force is applied to the plane of the connection end face 250, the pressing force is uniformly applied to all cores, so that variation in connection loss is suppressed. Further, the PMT optical connector has connection compatibility with an MT ferrule or an electric circuit board provided with an optoelectronic element. In the present embodiment, an example in which the plurality of core polymers 302 are arranged in one row only on the same plane has been shown, but the core polymers 302 may be arranged in a plurality of rows (multiple stages).
[0046] Here, it is preferable that the plane S connecting the central axes of the pair of guide pin holes 290 is parallel to the inner bottom surface 210 of the recess 213 and is disposed at a position lower than the inner bottom surface 210 by a predetermined distance δL. In this case, the predetermined distance δL is preferably 10 µm or more and 200 µm or less, more preferably 20 µm or more and 100 µm or less, and still more preferably 40 µm or more and 60 µm or less. Accordingly, the core polymer is drawn in a region of the clad polymer that is affected by friction from the inner bottom surface 210. Therefore, when drawing a plurality of core polymers by the Mosquito method, the occurrence of vortices or shaking can be preferably suppressed, so that a high-precision Mosquito waveguide can be formed.
[0047] (PMT Ferrule 200) Figs. 3 and 4 are schematic perspective views showing an example of the PMT ferrule 200 used in the PMT optical connector 100.
[0048] As shown in FIGS. 2 and 3, the PMT ferrule 200 for the PMT optical connector 100 according to the present embodiment includes a ferrule body having a recess 213 of a predetermined length L in the center, and a flange portion 235 protruding leftward, rightward and downward from the ferrule body. The inner side surface of the recess 213 consists of three surfaces: a side surface 211, a side surface 212 and an inner bottom surface 210.
[0049] Further, the outer side surface of the ferrule body consists of a side surface 220, a side surface 230, a bottom surface 240, a top surface 215 and a top surface 217. The top surface 215 and the top surface 217 are flush with each other. Furthermore, in the PMT ferrule 200 according to the present embodiment, a connection end surface 250 (an upright surface on one side) and an upright surface 251 on the other side are provided at an interval of the predetermined length L.
[0050] The flange portion 235 is formed with a bottom surface 241, a side surface 231 and a side surface 221, and is provided to protrude compared with the side surface 220, the side surface 230 and the bottom surface 240 of the ferrule body. Furthermore, guide holes 290 for inserting guide pins are provided in the connection end surface 250 and the upright surface 251. It should be noted that the inner bottom surface 210 of the recess 213 is provided at a position lower than the guide hole 290 for the guide pin. This is because it is necessary to lower the inner bottom surface 210 in order to align the core array of a mosquito waveguide 300 described later with the center of the guide hole 290 for the guide pin.
[0051] Figure 13 is a schematic perspective view showing a modified PMT ferrule 200. The PMT ferrules 200 in Figures 3 and 4 are formed to have the same external shape as internationally standardized MT ferrules for multi-core optical fibers. However, the modified PMT ferrule 200' maintains the same arrangement of multiple cores consisting of a pair of guide pin holes 290 and core polymer 302, while being formed to reduce the thickness of the ferrule body. Furthermore, in the modified PMT ferrule 200', the flange portion 235 protruding from the ferrule body is located only on the left and right sides, and the bottom surface 241 is flat without any protrusion. The modified PMT ferrule 200' is smaller than a normal MT ferrule while maintaining connection compatibility with MT ferrules, making it suitable for use in confined wiring areas such as electrical circuit boards.
[0052] (Jig 500) Figure 5 is a schematic perspective view showing an example of a jig 500 for manufacturing a PMT optical connector 100.
[0053] As shown in Figure 5, the jig 500 includes a pair of waveguide forming plates 510 and 520, a waveguide forming bottom plate 530, two sets of a pair of retaining plates 550 and 560 (one side and the other side), two sets of bottom plates 570, and a pair of end plates 580.
[0054] The jig 500 shown in Figure 5 has two spaces RP for holding the PMT ferrule 200, one on one side and one on the other. A waveguide-forming guide groove WG is provided between the pair of spaces RP, and a margin guide groove ML is provided outside the pair of spaces RP. The length LG of the waveguide-forming guide groove WG represents the actual length of the mosquito waveguide 300 excluding the PMT ferrule 200. Furthermore, the length MG of the margin guide groove ML is the length of the run-up required for the needle to move from its initial movement to stable movement and stable drawing. In this embodiment, the jig 500 is mainly made of metal members such as aluminum. Bolts and nuts are used to fix each member in place. In this embodiment, the length MG of the margin guide groove ML is preferably in the range of 6 mm to 70 mm.
[0055] Figure 6 is a schematic perspective view showing an example of the relationship between a pair of waveguide-forming plates 510 and 520 and a waveguide-forming bottom plate 530.
[0056] As shown in Figure 6, the pair of waveguide-forming plates 510 and 520 are placed on the waveguide-forming base plate 530 in the direction of the arrows indicated by the dashed lines and fixed at a distance of a predetermined width WH from each other. In this case, the width WH of the central protrusion on the waveguide-forming base plate 530 becomes the width of the mosquito waveguide 300, and the thickness of the mosquito waveguide 300 is obtained by subtracting the thickness LH of the central protrusion on the waveguide-forming base plate 530 from the combined thickness KH of the pair of waveguide-forming plates 510 and 520.
[0057] Next, Figure 7 is a schematic perspective view showing an example of the relationship between a pair of retaining plates 550 and 560 and the bottom plate 570.
[0058] As shown in Figure 7, in Figure 5, the vertical wall 575, which is not shown, is fixed to the recess of the base plate 570 along the direction of the arrow. Also, the pair of retaining plates 550 and 560 are placed on the base plate 570 along the direction of the arrow.
[0059] The support bottom surface S241, which is a recess in the vertical wall 575, is formed to be able to hold the bottom surface 241 of the ferrule 200, and the support bottom surface S240 of the bottom plate 570 is also formed to be able to hold the bottom surface 240 of the ferrule 200.
[0060] Furthermore, the support wall S231 of the retaining plate 550 is formed to be able to hold the side surface 231 of the ferrule 200, and the support wall S230 of the retaining plate 550 is formed to be able to hold the side surface 230 of the ferrule 200. Similarly, the wall S221 of the retaining plate 560 is formed to be able to hold the side surface 221 of the ferrule 200, and the support wall S220 of the retaining plate 560 is formed to be able to hold the side surface 220 of the ferrule 200.
[0061] The width WH of the central protrusion on the base plate 570 becomes the width of the margin guide groove ML, and the thickness of the margin guide groove ML is obtained by subtracting the thickness LH of the central protrusion on the base plate 570 from the thickness KH of the retaining plates 550 and 560. In this embodiment, it is preferable that the thickness and width of the margin guide groove ML, the depth and width of the recess 213 of the PMT ferrule, and the thickness and width of the waveguide forming guide groove WG are the same and arranged on the same plane. This ensures stable resin coating by the mosquito method and allows for favorable drawing of the mosquito waveguide 300. However, the invention is not limited to this, and at least one or both of the width and thickness of the margin guide groove ML may be made larger or smaller.
[0062] (Manufacturing Method of PMT Optical Connector 100) The manufacturing method of the PMT optical connector 100 will be described below. Figure 8 is a diagram showing an example of the manufacturing process of the PMT optical connector 100 in this embodiment, and Figures 9 to 112 are schematic perspective views showing an example of the manufacturing method of the PMT optical connector 100.
[0063] First, the jig 500 is assembled as shown in Figure 8. In this embodiment, the jig 500 shown in Figure 5 is formed by screw fastening (step S1).
[0064] Next, as shown in Figure 9, the ferrules 200 of the PMT optical connector 100 are fitted into the space RP of the jig 500 (step S2). Here, the jig 500 is formed such that the inner bottom surface 210 of the ferrule 200 of the PMT optical connector 100 and the bottom surface of the waveguide forming guide groove WG of the jig 500 are extremely flat. In addition, the jig 500 is formed such that the top surfaces 215 and 217 of the ferrule 200 are extremely flat with the upper surfaces of the waveguide forming plate 510 and waveguide forming plate 520 of the jig 500.
[0065] Next, as shown in Figure 10, the cladding material is applied (step S3). Here, the cladding material is applied from one of the margin guide grooves ML to the inner surface of the recess formed by the side 211, side 212 and inner bottom surface 210 of one of the ferrules 200, to the waveguide forming guide groove WG, to the inner surface of the recess of the other ferrule 200, and to the other margin guide groove ML. In this embodiment, the cladding material is a UV-curing resin for cladding, and is left to stand until the thickness becomes uniform. In this case, the width of the inner surface of the recess is preferably 2.0 mm or more and 4 mm or less, and more preferably 2.5 mm or more and 3.5 mm or less. The film thickness of the UV-curing resin for cladding is preferably 0.8 mm or more and 1.8 mm or less, and more preferably 1.2 mm or more and 1.4 mm or less. As a result, the jig 500 is formed such that the flatness between the inner bottom surface 210 of the ferrule 200 of the PMT optical connector 100 and the bottom surface of the waveguide forming guide groove WG of the jig 500 is extremely high, so that the cladding of the mosquito waveguide 300 can be formed stably.
[0066] Next, a reference adjustment is performed (step S4). This reference adjustment is performed because it is unclear whether the surface on which the jig 500 is installed is horizontal or not. In other words, in the mosquito method in this embodiment, the needle at the tip of a syringe is inserted into the uncured UV-curing resin for cladding, and while a UV-curing resin for the core with a high refractive index is dispensed from the needle tip using a dispenser, the syringe (needle tip) is moved in an arbitrary direction by a multi-axis robot. Therefore, the height reference of the syringe (needle tip) is adjusted, and an offset setting is made for bending, etc., in the jig 500. Alternatively, coordinates may be acquired at the end face corner of the ferrule 200 of the PMT optical connector 100, and the height of the jig 500 may be adjusted.
[0067] Next, the drawing program is executed to extrude a UV-curable resin for the core with a high refractive index from the needle tip and draw the core (step S5). Here, as shown in Figure 10, the core is drawn from one margin guide groove ML to the inner surface of the recess consisting of the side surface 211, side surface 212 and inner bottom surface 210 of one ferrule 200, to the waveguide forming guide groove WG, to the inner surface of the recess of the other ferrule 200, and to the other margin guide groove ML. Here, it is preferable that the viscosity of the UV-curable resin for the cladding is lower than the viscosity of the UV-curable resin for the core. The viscosity of the UV-curable resin for the cladding is preferably 1000 Pa·s or more and 7000 Pa·s or less, and the viscosity of the UV-curable resin for the core is preferably 20000 Pa·s or more and 90000 Pa·s or less. As a result, the two resins do not mix easily, and the core formed by the drawing program can maintain its shape within the cladding for a predetermined time.
[0068] Next, UV irradiation is performed (step S6). As shown in Figure 11, during UV irradiation, the UV light is irradiated from one of the margin guide grooves ML to the inner surface of the recess formed by the side 211, side 212 and inner bottom surface 210 of one of the ferrules 200, to the waveguide forming guide groove WG, to the inner surface of the recess of the other ferrule 200, and to the other margin guide groove ML. In this case, the resin hardens, and the core arrangement is formed according to the programmed trajectory and drawing. By changing the drawing program, it is possible to form cores corresponding to the optical fiber or optical waveguide to be connected. Furthermore, by drawing the coating method of the UV-curing resin for the core to change gradually, it is possible to change the core size, change from multi-core to single-core, change from single-core to multi-core, change the pitch, etc. Also, single-mode and multi-mode can be handled by changing the curing speed depending on the intensity of the UV irradiation. Furthermore, if the hardness of the mosquito waveguide 300 is insufficient for the optical fiber, an optical connection may be made between the two using a refractive index matching material.
[0069] Next, the jig 500 is disassembled (step S7). In this embodiment, by releasing the screw fastenings of the jig 500, a PMT optical connector 100 can be obtained in which a waveguide is also formed in the excess guide groove ML. In this case, by disassembling the jig 500, the waveguide can be easily removed without damaging it.
[0070] Then, UV irradiation is performed again to eliminate any insufficiently cured areas (Step S8). Alternatively, secondary curing may be performed using a heater in an environment of around 100 degrees Celsius. Finally, the outer ends of the ferrule 200, i.e., the excess guide groove ML, are removed (Step S9). As a result, the PMT optical connector 100 shown in Figure 1 can be obtained.
[0071] Thus, in the novel mosquito method for forming the PMT optical connector 100 according to the present invention, by providing one and the other marginal guide grooves ML which are run-up recesses, the movement of the multi-axis robot and dispenser can be stabilized, making it possible to stably change the core arrangement in three dimensions. Therefore, it is possible to manufacture and miniaturize optical communication devices such as FIFOs. Furthermore, since the positioning of the core and ferrule 200 of the mosquito waveguide 300 can be easily performed, a PMT optical connector 100 that can connect mosquito waveguides with high efficiency can be obtained.
[0072] In the present invention, the PMT ferrule 200 corresponds to the "PMT ferrule," the side surface 211, the side surface 212 and the inner bottom surface 210 correspond to the "recess," the inner bottom surface 210 corresponds to the "inner bottom surface of the recess," and the side surface 211 and the side surface 212 correspond to the "inner sides of the recess."
[0073] Furthermore, the top surface 215 and top surface 217 correspond to the "top surface of the recess," the bottom surface 240 corresponds to the "outer bottom surface of the recess," the side surfaces 220 and 230 correspond to the "outer side surfaces of the recess," the bottom surface 241, side surfaces 231 and 221 correspond to the "protruding portion," and the guide pin hole 290 corresponds to the "guide pin hole."
[0074] Furthermore, space RP corresponds to a "hole into which a PMT ferrule can be fitted," waveguide forming guide groove WG corresponds to a "flush recess," margin guide groove ML corresponds to a "preparation recess," and jig 500 corresponds to a "jig for manufacturing a PMT optical connector."
[0075] Furthermore, the waveguide forming plate 510 corresponds to the "first jig," the waveguide forming plate 520 corresponds to the "second jig," the waveguide forming bottom plate 530 corresponds to the "third jig," the holding plate 550 corresponds to the "fourth jig," the holding plate 560 corresponds to the "fifth jig," and the bottom plate 570 corresponds to the "sixth jig."
[0076] Furthermore, step S2 corresponds to the "fitting process," step S3 corresponds to the "coating process," step S5 corresponds to the "optical waveguide formation process," step S6 corresponds to the "UV irradiation process," step S7 corresponds to the "jig removal process," step S9 corresponds to the "removal process," and steps S1 to S9 correspond to the "method for manufacturing a PMT optical connector."
[0077] While the above describes a preferred embodiment of the present invention, the present invention is not limited thereto. It will be understood that various other embodiments can be made without departing from the spirit and scope of the present invention. Furthermore, although the operation and effects of the configuration of the present invention are described in this embodiment, these operation and effects are examples and do not limit the present invention.
[0078] 100 PMT optical connector 200 PMT ferrule 210 Inner bottom surface (inner bottom surface of recess) 211 Side surface (side surface of recess) 212 Side surface (side surface of recess) 213 Recess 215 Top surface 217 Top surface 240 Bottom surface 230 Side surface 235 Flange 221 Side surface (side surface of flange) 231 Side surface (side surface of flange) 241 Bottom surface (bottom surface of flange) 250 Connection end surface 251 Upright surface 290 Guide hole 300 Mosquito waveguide 301 Clad polymer 302 Core polymer 500 Jig 510 Waveguide forming plate 520 Waveguide forming plate 530 Waveguide forming bottom plate 550 Retaining plate 560 Retaining plate 570 Base plate ML, clearance guide groove RP, space WG, waveguide forming guide groove
Claims
1. A PMT optical connector comprising a mosquito waveguide and a PMT ferrule, wherein the PMT ferrule has a recess on its top surface, the inner bottom surface and both inner sides of the recess are formed as planes, the mosquito waveguide is arranged to extend from the other end of the recess toward the one end, and the upper surface of the mosquito waveguide is coplanar with the top surface of the PMT ferrule.
2. The PMT optical connector according to claim 1, wherein the PMT ferrule has a pair of guide holes on the outer sides of both inner surfaces of the recess, the guide holes are formed in a cylindrical shape from one end to the other of the PMT ferrule, and the surface S connecting the central axes of the pair of guide holes is provided 10 μm to 200 μm on the top surface side of the inner bottom surface of the recess.
3. The PMT optical connector according to claim 2, wherein the mosquito waveguide comprises a clad polymer and a plurality of core polymers, and the plurality of core polymers are provided on the same plane as the surface S connecting the central axes of a pair of guide holes.
4. The PMT optical connector according to claim 1, wherein the mosquito waveguide comprises a cladding polymer and a plurality of core polymers, the core polymer having a gradually changing core diameter and / or core pitch in the extending direction.
5. A photoelectric circuit board comprising an electrical circuit board equipped with a photoelectric element and a PMT optical connector as described in claim 1, wherein an optical waveguide extending from the photoelectric element and the mosquito waveguide of the PMT optical connector are optically connected.
6. A PMT ferrule having a recess provided on the top surface, a pair of guide holes provided on both outer sides of the recess, and a flange portion on the other end projecting inwards toward both inner sides, wherein the recess is formed extending from one end to the other, the inner bottom surface and both inner sides of the recess are formed as flat surfaces, the top surface is formed as a flat surface from one end to the other, the mosquito waveguide is arranged to extend from the other end of the recess of the ferrule body toward the one end, and the surface S connecting the central axes of the pair of guide holes is provided 10 μm to 100 μm on the top surface side of the inner bottom surface of the recess.
7. A jig for manufacturing a PMT optical connector by the mosquito method, comprising: a hole for fitting a PMT ferrule; a flush recess that becomes flush with the inner bottom surface and inner side surfaces of the recess of the PMT ferrule when the PMT ferrule is fitted into the hole; and a run-up recess for running a dispenser.
8. The jig according to claim 7, wherein the flush recess is composed of a first jig that communicates flush with one inner side surface of the recess, a second jig that communicates flush with one inner side surface of the recess and is provided opposite to the first jig, and a third jig that communicates flush with the inner bottom surface, and the first jig and the second jig are each formed to be separable from the third jig.
9. The jig according to claim 8, wherein the approach recess is comprised of a fourth jig that forms the hole and communicates flush with one inner side surface of the recess, a fifth jig provided opposite to the fourth jig that forms the hole and communicates flush with the other inner side surface of the recess, and a sixth jig that forms the hole and communicates flush with the inner bottom surface of the recess.
10. The jig according to claim 9, wherein the fourth jig, the fifth jig, and the sixth jig are provided on both ends of the first jig, the second jig, and the third jig, respectively.
11. A method for manufacturing a PMT optical connector, comprising: a fitting step of fitting one or more PMT ferrules into a jig; a coating step of applying uncured UV-curing resin for cladding to the pre-run recess and the flush recess of the jig; a waveguide forming step of dispensing UV-curing resin for cores using a dispenser from one of the pre-run recesses, through the flush recess, to the other pre-run recess to form a mosquito waveguide; a UV irradiation step of irradiating the mosquito waveguide obtained in the waveguide forming step with ultraviolet light; a step of removing the jig after the UV irradiation step; and a removal step of removing the optical waveguide formed in the pre-run recess after the step of removing the jig.