JP2010079027A - Optical receptacle and optical module using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical receptacle in which the insertion loss of light is reduced even when a lateral road is applied to a plug inserted into the optical receptacle and to provide an optical module. <P>SOLUTION: The optical receptacle 1 includes: an optical fiber 12; a ferrule 10 which holds the optical fiber 12 in an inner hole; a cylindrical split sleeve 20 which holds the ferrule 10 on one end side of the inner hole and has a slit 21 in the longitudinal direction; and a recessed part 22 and a projected part 11 provided in the peripheral direction on the outer peripheral face 13 of the ferrule 10 and the inner peripheral face 23 of the split sleeve 20 corresponding to the outer peripheral face 13 for engaging the ferrule 10 and the split sleeve 20. The shift of optical axes of the optical fiber 12 and an optical fiber 51 is suppressed by the recessed part 22 and the projected part 11. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an optical receptacle used for an optical communication module or the like.

  In recent years, optical receptacles are used to optically couple optical elements and optical fibers in optical communication technology that supports high-speed and large-capacity information communications. In optical receptacles, efforts are being made to reduce transmission loss of optical signals.

For example, in Patent Document 1, as shown in FIG. 6, a built-in ferrule 110 is inserted into one end (base end) of an inner hole of a split sleeve 120 that is hollow and easily elastically expands and contracts in the radial direction. An optical receptacle 101 is disclosed in which a grip ring 130 is press-fitted to the outer periphery of the end. The grip ring 130 restrains the proximal end side of the split sleeve 120 from expanding in the radial direction and prevents the built-in ferrule 110 from dropping from the split sleeve 120. For this reason, even if the length of the built-in ferrule 110 is shortened, the built-in ferrule 110 does not easily fall off from the split sleeve 120, and accordingly, the insertion length of the plug ferrule 151 into the optical receptacle 101 can be increased. It is said that the insertion loss of light at the connection point can be reduced.
Japanese Patent Laid-Open No. 10-332988

  However, in the optical receptacle 101 described in Patent Document 1, when the plug ferrule 151 is inserted into the optical receptacle 101 and a lateral load is applied to the plug ferrule 151, the split sleeve 120 on the side where the plug ferrule 151 is inserted. The end portion of the plug ferrule 151 serves as a fulcrum and the tip of the plug ferrule 151 serves as an action point, and the split sleeve 120 is easily bent near the action point. For this reason, the optical axis of the plug ferrule 151 and the ferrule 110 which contact | abut has shifted | deviated, and it had the problem that the insertion loss of light arises.

  Therefore, the present invention has been made in view of the above, and an object of the present invention is to provide a highly reliable optical receptacle and optical module capable of reducing the insertion loss of light even with respect to a lateral load. It is in.

  To achieve the above object, the present invention provides an optical fiber, a ferrule for holding the optical fiber in the inner hole, a cylindrical split having a slit in the longitudinal direction, holding the ferrule on one end side of the inner hole. And an uneven portion for engaging the ferrule and the split sleeve in the circumferential direction of the outer peripheral surface of the ferrule and the inner peripheral surface of the split sleeve corresponding to the outer peripheral surface.

  Moreover, the said uneven | corrugated | grooved part is provided in the perimeter of the outer peripheral surface of the said ferrule and the inner peripheral surface of the said split sleeve, It is characterized by the above-mentioned.

  An optical fiber, a ferrule that holds the optical fiber in the inner hole and has a first recess in the circumferential direction of the outer peripheral surface, and holds the ferrule on one end side of the inner hole and corresponds to the first recess. A cylindrical split sleeve having a second recess at the position of the inner peripheral surface and having a slit in the longitudinal direction, and a ring that engages with the first recess of the ferrule and the second recess of the split sleeve. It is characterized by.

  The ring may have a slit in the axial direction.

  An optical module comprising: the optical receptacle according to any one of the above; an optical element disposed so as to be optically coupled to the optical fiber; and a housing that accommodates the optical element and has the optical receptacle attached thereto. It is characterized by being.

  According to the present invention, an optical fiber, a ferrule that holds the optical fiber in the inner hole, and a cylindrical split sleeve that holds the ferrule on one end side of the inner hole and has a slit in the longitudinal direction, By providing the outer peripheral surface of the ferrule and the concavo-convex portion for engaging the ferrule and the split sleeve in the circumferential direction of the inner peripheral surface of the split sleeve corresponding to the outer peripheral surface, the ferrule and the split sleeve are not easily displaced in the axial direction. Therefore, bending of the split sleeve is suppressed.

  Therefore, according to the present invention, it is possible to provide a highly reliable optical receptacle and optical module capable of reducing light insertion loss even when a load is applied from the lateral direction.

  Hereinafter, an optical receptacle and an optical module according to the present invention will be described in detail with reference to the drawings. The following embodiments are illustrative of the present invention and are not limiting. In addition, in each figure, about the common member, the same code | symbol is attached | subjected and the overlapping description is abbreviate | omitted.

(Embodiment 1)
As shown in FIG. 1, the optical receptacle 1 according to the first embodiment of the present invention includes a ferrule 10 that holds an optical fiber 12 in an inner hole, and holds the ferrule 10 on the one end 20b side of the inner hole. And a cylindrical split sleeve 20 having a slit 21. Convex portions 11 are provided in the circumferential direction of the outer peripheral surface 13 of the tip of the ferrule 10, and concave portions 22 are provided at corresponding positions on the inner peripheral surface 23 of the split sleeve 20 in contact with the outer peripheral surface 13. 11 and the recessed part 22 are fitted, and the front-end | tip part of the ferrule 10 is inserted in the rear-end part of the split sleeve 20. FIG. In addition, the split sleeve 20 is provided with a through hole (inner hole) into which the plug 50 having the plug ferrule 51 fixed from the distal end portion is inserted. Then, the tip end of the optical fiber 12 held by the ferrule 10 and the tip end of the optical fiber 52 of the plug 50 are abutted coaxially so that the optical fiber 12 and the optical fiber 52 are optically connected.

  Here, the split sleeve 20 has a through hole having an inner diameter substantially the same as the outer diameter of the plug ferrule 51 of the optical connector plug 50 from one end (front end) 20a to the other end (rear end) 20b, and from one end 20a of the cylindrical wall. It is a cylinder in which a slit 21 is formed up to the other end 20b. A concave portion 22 is formed in the circumferential direction on the inner peripheral surface 23 of the through hole in the vicinity of the other end 20b.

Examples of the material constituting the split sleeve 20 include zirconium oxide (zirconia), aluminum oxide (alumina), mullite, silicon nitride, silicon carbide, aluminum nitride and the like, ceramics containing these as main components, and glass such as crystallized glass. Metals such as ceramics, phosphor bronze, beryllium copper, brass, and stainless steel, and plastics such as epoxy and liquid crystal polymer are listed. Among them, zirconia ceramics (ceramics mainly composed of zirconia) with excellent weather resistance and toughness are listed. Is preferred. Among zirconia-based ceramics, in particular, at least one selected from the group consisting of zirconium oxide (ZrO ₂ ) as a main component and Y ₂ O ₃ , CaO, MgO, CeO ₂ , Dy ₂ O _{3 and the} like is used as a stabilizer. The partially stabilized zirconia ceramics (mainly tetragonal crystals) are included as a more preferable material from the viewpoint of wear resistance and elastic deformation.

  Next, the ferrule 10 is formed of a cylindrical body having an outer diameter substantially the same as the outer diameter of the plug ferrule 51 of the optical connector plug 50. The convex portion 11 is formed in the circumferential direction of the outer peripheral surface 13 of the ferrule 10 at a position where the concave portion 22 of the split sleeve 20 comes when the ferrule 10 is inserted into the split sleeve 20.

Ferrule 10 is made of a material such as zirconium oxide (zirconia), aluminum oxide (alumina), mullite, silicon nitride, silicon carbide, aluminum nitride, or the like, ceramics containing these as main components, or glass ceramics such as crystallized glass. Metals such as phosphor bronze, beryllium copper, brass, and stainless steel, plastics such as epoxy and liquid crystal polymer, etc. Among them, zirconia-based ceramics (ceramics mainly composed of zirconia) excellent in weather resistance and toughness are preferable. It is. Among zirconia-based ceramics, in particular, at least one selected from the group consisting of zirconium oxide (ZrO ₂ ) as a main component and Y ₂ O ₃ , CaO, MgO, CeO ₂ , Dy ₂ O _{3 and the} like is used as a stabilizer. The partially stabilized zirconia ceramics (mainly tetragonal crystals) are included as a more preferable material from the viewpoint of wear resistance and elastic deformation.

  The rear end portion of the ferrule 10 protruding from the rear end portion of the split sleeve 20 is inserted into the through hole 42 of the holder 40. Here, the holder 40 is made of, for example, a metal such as stainless steel, copper, iron, or nickel. In addition, a recessed insertion portion 41 for press-fitting one end of the sleeve case 30 is formed, and a through hole 42 penetrating from the insertion portion 41 to the rear end surface is formed at a substantially central portion of the insertion portion 41. As described above, the rear end portion of the ferrule 10 is inserted into the through hole 42 of the holder 40, and the end surface of the other end 20 b of the split sleeve 20 and the bottom surface of the insertion portion 41 of the holder 40 are brought into contact with each other. Yes.

  Further, as shown in FIG. 1, the sleeve case 30 is fixed to the insertion portion 41 of the holder 40 by, for example, press-fitting.

  The sleeve case 30 is a substantially cylindrical tubular member for accommodating the split sleeve 20, and includes an opening 30 a into which the plug ferrule 51 of the plug 50 is inserted and a fixing portion 30 b for fixing to the holder 40. Have. The diameter of the space for accommodating the split sleeve 20 in the sleeve case 30 is slightly larger (for example, 200 μm) than the outer diameter of the split sleeve 20, and is smaller than the outer diameter of the split sleeve 20 in the opening 30a. The opening 30a is a part for guiding the plug 50 when the plug 50 is inserted, and is formed in a tapered shape toward the back side. The opening end diameter of the opening 30 a is slightly larger (for example, 0.2 mm) than the outer diameter of the plug ferrule 51. As described above, the joint 30b is fixed to the holder 40 by press fitting or the like.

  By inserting the sleeve case 30 into the holder 40 as described above, the split sleeve 20 is stored inside the sleeve case 30. At this time, it is preferable that the central axis of the sleeve case 30 and the central axis of the split sleeve 20 coincide. The space for housing the split sleeve 20 in the sleeve case 30 communicates with the outside through the opening 30a. When the holder 40, the sleeve case 30, the split sleeve 20, and the ferrule 10 are assembled, the sleeve case 30 The opening 30a and the split sleeve 20 form a space in which the plug ferrule 51 is accommodated.

  The material constituting the sleeve case 30 includes synthetic resin (thermoplastic resin, thermosetting resin, etc.), metal (stainless steel, copper, iron, nickel, etc.), ceramics (aluminum oxide (alumina), zirconium oxide (zirconia), etc.) ), Glass (quartz and the like), and the like. Among these, considering the fixation with the holder 40, it is preferable to use the same material as the holder 40, for example, stainless steel in order to increase the reliability by matching the thermal expansion coefficient.

  Here, the behavior when a lateral load is applied to the plug ferrules 51 and 151 after inserting the plug ferrules 51 and 151 of the optical receptacles of the present invention and the conventional example will be described with reference to FIG.

  FIG. 2A is a schematic view showing a state in which a lateral load is applied to the plug ferrule 51 after the plug ferrule 51 is inserted into the optical receptacle of the present invention, and FIG. 2B is a diagram showing a plug ferrule in the conventional optical receptacle. It is a schematic diagram which shows the state which applied the lateral load to the plug ferrule 151 after inserting 151. FIG.

  The ferrule 10 and the plug ferrule 51 are gripped by the inner peripheral surface 23 of the split sleeve 20, the tip surfaces are brought into contact with each other, and the optical fiber 12 and the optical fiber 52 are optically coupled. In the conventional example of FIG. 2B, when a downward lateral load is applied to the plug ferrule 151 as indicated by an arrow in the figure, the split sleeve 120 is deformed so as to be bent, and the upper surface of the split sleeve 20 is 120U moves to the left in the axial direction, and the lower surface 120L sandwiching the axial center of the split sleeve 20 with respect to the upper surface 120U moves to the right in the axial direction. For it. In the example of FIG. 2A of the present invention, similarly, when a downward lateral load is applied to the plug ferrule 51 as indicated by an arrow in the figure, the concave portion 22 and the convex portion 11 are engaged. In addition, the movement of the upper surface 20U and the lower surface 20L of the split sleeve 20 in the axial direction is restricted, so that the deformation that causes the split sleeve 20 to be bent is suppressed.

  As described above, in the optical receptacle 1 of the present invention, the concave and convex portions that engage the ferrule 10 and the split sleeve 20 with the circumferential direction of the outer peripheral surface 13 of the ferrule 10 and the inner peripheral surface 23 of the split sleeve 20 corresponding to the outer peripheral surface 13. Since the deformation of the split sleeve 20 is suppressed, the amount of deviation between the optical axis of the optical fiber 12 and the optical axis of the optical fiber 52 of the plug ferrule 51 is reduced, and the diameter of the split sleeve 20 is reduced. The deformation (expansion) in the direction is also suppressed.

  Therefore, according to the optical receptacle 1 of the present invention, it is possible to provide the optical receptacle 1 and the optical module 3 that can reduce the insertion loss of light even when a load is applied from the lateral direction to the plug 50 side.

  Here, the processing method of the recessed part 22 of the internal peripheral surface 23 of the split sleeve 20 of this invention is demonstrated. For example, if the split sleeve 20 is made of ceramics, before the slit 21 is processed, a so-called electrodeposition tool in which diamond abrasive grains are applied to a cylindrical grindstone by electrodeposition is inserted into the through hole of the split sleeve, The concave portion 22 can be formed by rotating while making contact with the inner peripheral surface of the split sleeve 20. If the split sleeve 20 is made of metal, the recess 22 can be formed by turning with a lathe before the slit 21 is processed.

  Moreover, the convex part 11 formed in the outer peripheral surface 13 of the ferrule 10 of this invention can be formed by turning the outer peripheral surface 13 of the ferrule 10.

(Embodiment 2)
As shown in FIG. 3, the optical receptacle 1 according to the second embodiment of the present invention includes a ferrule 10 that holds an optical fiber 12 in an inner hole, a ferrule 10 that is held at one end of the inner hole, and a longitudinal direction. And a cylindrical split sleeve 20 having a slit 21. Concave portions 14 are provided in the circumferential direction of the outer peripheral surface of the distal end portion of the ferrule 10, and convex portions 24 are provided at corresponding positions on the inner peripheral surface 23 of the split sleeve 20 in contact with the outer peripheral surface. The front end portion of the ferrule 10 is inserted into the rear end portion of the split sleeve 20 by fitting the convex portion 24. In addition, the split sleeve 20 is provided with a through hole into which a plug 50 having a plug ferrule 51 fixed from the tip portion is inserted. And the front-end | tip of the optical fiber 12 hold | maintained at the ferrule 10 and the front-end | tip of the optical fiber 52 of the plug 50 are faced | matched coaxially, and are optically connected.

  In the second embodiment, as compared with the first embodiment, a concave portion 14 is formed instead of the convex portion 11 on the outer peripheral surface of the ferrule 10, and a convex portion 24 is formed instead of the concave portion 22 on the inner peripheral surface 23 of the split sleeve 20. However, it is the same except that the positional relationship of the unevenness is reversed.

  Here, the convex portion 24 of the inner peripheral surface 23 of the split sleeve 20 can be formed by turning from both ends of the split sleeve 20 before the slit 21 of the split sleeve 20 is processed.

  Further, the recess 14 on the outer peripheral surface of the ferrule 10 can be formed by turning the outer peripheral surface of the ferrule 10.

(Embodiment 3)
As shown in FIG. 4A, the optical receptacle 1 according to the third embodiment of the present invention holds the optical fiber 12 in the inner hole and has a first recess 15 in the circumferential direction of the outer peripheral surface 13. A cylindrical shape that holds the ferrule 10 on the one end 20b side of the inner hole (through hole), has a second recess 25 at the position of the inner peripheral surface 23 corresponding to the first recess 15, and has a slit 21 in the longitudinal direction. And a ring 45 that engages with the first recess 15 of the ferrule 10 and the second recess 25 of the split sleeve 20. In addition, the split sleeve 20 is provided with a through hole into which a plug 50 having a plug ferrule 51 fixed from the tip portion is inserted. Then, the tip end of the optical fiber 12 held by the ferrule 10 and the tip end of the optical fiber 52 of the plug 50 are abutted coaxially so that the optical fiber 12 and the optical fiber 52 are optically connected.

  In the third embodiment, the first recess 15 and the second recess 25 are provided on both the outer peripheral surface 13 of the ferrule 10 and the inner peripheral surface 23 of the split sleeve 20 as compared with the first and second embodiments, respectively, and the ring 45 is the first one. The first and second recesses 15 and 25 are the same except that they are inserted into the first and second recesses 15 and 25 so as to connect the first and second recesses 15 and 25.

  As shown in FIG. 4B, the ring 45 is preferably provided with a single slit 46 in the axial direction, so that it can be easily inserted into the outer peripheral surface 13 of the ferrule 10. Alternatively, as shown in FIG. 4C, it is preferable to have a configuration in which two slits 47 are provided in the axial direction, that is, a configuration in which two semicircular portions are combined into one ring 45. It becomes easy to insert on the outer peripheral surface 13 of the ferrule 10. Then, the ferrule 10 with the ring 45 inserted is inserted into the opening of the one end 20b of the split sleeve 20 and assembled.

  In any of the first to third embodiments of the present invention, the cross-sectional shape of the concave portion and the convex portion is illustrated as a rectangle. However, the effects of the present invention can be achieved. Depending on the cross-sectional shape, insertion into the split sleeve 20 can be made smooth.

  Next, FIG. 5 is a cross-sectional view of the optical module 3 provided with the optical receptacle 1 according to the present invention. The optical module 3 includes an optical receptacle 1 and an optical element unit 60. The optical element unit 60 includes an optical element 61, a lens 62, and a housing 63.

  The optical element 61 is a light emitting element for emitting light toward the optical fiber 12 inserted in the ferrule 10 or a light receiving element for receiving light derived through the optical fiber 12. Examples of the light emitting element include a semiconductor laser and an LED (light emitting diode), and examples of the light receiving element include a receiving PD (photodiode).

  When the optical element 61 is a light emitting element, the lens 62 collects light emitted from the light emitting element and introduces it into the optical fiber 12. When the optical element 61 is a light receiving element, the lens 62 emits from the optical fiber 12. It is a member having a function of collecting the collected light and introducing it into the light receiving element.

  The housing 63 is a member for housing the optical element 61 and the lens 62, and is joined to the optical receptacle 1 by welding, for example. Examples of the material constituting the housing 63 include weldable materials such as stainless steel, copper, iron, and nickel, and stainless steel is preferable from the viewpoint of corrosion resistance and weldability.

  In the optical module 3 configured as described above, the optical fiber 12, the ferrule 10 that holds the optical fiber 12 in the inner hole, the ferrule 10 is held on one end side 20b of the inner hole, and is slit in the longitudinal direction. And an irregularity for engaging the ferrule 10 and the split sleeve 20 in the circumferential direction of the inner peripheral surface 23 of the split sleeve 20 corresponding to the outer peripheral surface 13 and the outer peripheral surface 13 of the ferrule 10. By providing the portions 11, 22, 14, 24, 15, and 25, the ferrule 10 and the split sleeve 20 are not easily displaced in the axial direction, so that the bending of the split sleeve 20 is suppressed.

  Therefore, according to the present invention, it is possible to obtain a highly reliable optical module 3 that can reduce the insertion loss of light even when a load is applied from the lateral direction.

It is sectional drawing which shows an example of the optical receptacle which concerns on Embodiment 1 of this invention. (A) is a schematic diagram showing a state in which a lateral load is applied to the plug ferrule after the plug ferrule is inserted into the optical receptacle of the present invention, and (b) is a state in which a lateral load is applied to the plug ferrule in the conventional example. It is a schematic diagram which shows. It is sectional drawing which shows an example of the optical receptacle which concerns on Embodiment 2 of this invention. (A) is sectional drawing which shows an example of the optical receptacle which concerns on Embodiment 3 of this invention, (b) And (c) is a front view which shows an example of embodiment of a ring. It is sectional drawing which shows an example of embodiment of the optical module which employ | adopted the optical receptacle shown in FIG. It is sectional drawing which shows the example of the conventional optical receptacle.

Explanation of symbols

1: optical receptacle,
3: Optical module,
10: Ferrule,
11: convex part,
12: Optical fiber,
13: outer peripheral surface,
14: recess,
15: 1st recessed part,
20: Split sleeve,
21: slit,
22: recess,
23: inner peripheral surface
24: convex part,
25: second recess,
30: Sleeve case,
40: Holder
50: Plug,
51: Ferrule,
52: Optical fiber
60: Optical element unit,
61: optical element,
62: Lens
63: Housing

Claims (5)

An optical fiber, a ferrule that holds the optical fiber in the inner hole, and a cylindrical split sleeve that holds the ferrule on one end side of the inner hole and has a slit in the longitudinal direction;
An optical receptacle, wherein an uneven portion for engaging the ferrule and the split sleeve is provided in a circumferential direction of an outer peripheral surface of the ferrule and an inner peripheral surface of the split sleeve corresponding to the outer peripheral surface. The optical receptacle according to claim 1, wherein the concavo-convex portion is provided on the entire outer periphery of the ferrule and the inner periphery of the split sleeve. Optical fiber,
A ferrule that holds the optical fiber in the inner hole and has a first recess in the circumferential direction of the outer peripheral surface;
A cylindrical split sleeve that holds the ferrule on one end side of the inner hole and has a second recess at the position of the inner peripheral surface corresponding to the first recess, and has a slit in the longitudinal direction;
An optical receptacle comprising a ring that engages with a first recess of the ferrule and a second recess of the split sleeve. The optical receptacle according to claim 3, wherein the ring has a slit in an axial direction. An optical receptacle according to any one of claims 1 to 4,
An optical element arranged to optically couple with the optical fiber;
A housing containing the optical element and having the optical receptacle attached thereto;
An optical module comprising:

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