JP2007114673A - Optical module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical module that requires a smaller number of parts, that has an ability to reduce man-hour, and that thereby excels in cost effectiveness. <P>SOLUTION: The optical module is equipped with a cap holder in which a ferrule is inserted in one end and in which a partition plate with an opening in the center is integrally formed. A dimensional tolerance is reduced in the inner diameter of the cap holder and in the outer diameter of the ferrule. A transparent plate is attached to the partition plate in a manner blocking the opening. Also, an abutting part is formed in the section where the partition plate and the cap holder are in contact with each other. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an optical module having an optical semiconductor element such as a photodiode or a light emitting diode.

  A conventional optical module 90 will be described with reference to FIG. FIG. 6 is a cross-sectional view of the optical module 90. The optical module 90 includes a stem 23, an avalanche photodiode 25, a ferrule holder 80, a stem holder 81, a lens 82, a stem cap 83, and a stem lead 84 (see Patent Documents 1 and 2).

  The avalanche photodiode 25 is disposed on the stem 23 so as to face the lens 82. A stem 82 is attached to the stem cap 83. The stem cap 83 is resistance welded to the stem 23. The stem 23 is connected to a stem lead 84.

  Ferrule holder 80 is attached to stem holder 81. The stem holder 81 is fixed to the stem 23.

  The ferrule 22 has the optical fiber 21 inserted through a center line connecting both end faces. The end surface of the ferrule 22 facing the lens 82 is polished obliquely.

  If the ferrule 22 is inserted into the ferrule holder 80, the optical module 90 can be connected to an optical communication network or an optical communication device. When the ferrule 22 is inserted into the ferrule holder 80, the optical module 90 uses the lens 82 to align the optical module 90 in the optical axis direction and to adjust the optical module 90 in the direction perpendicular to the optical axis. Need a wick.

JP 2002-258114 A JP-A-10-206700

  However, the optical module 90 includes the stem 23, the ferrule holder 80, the stem holder 81, the lens 82, the stem cap 83, and the like, and there is a problem that the number of parts increases. Further, the optical module 90 has a problem that an alignment process in the optical axis direction of the optical module 90 and an alignment process in a direction perpendicular to the optical axis of the optical module 90 are necessary. Furthermore, the optical module 90 has a problem that an expensive lens 82 is required.

  The present invention has been made to solve the above-described problems, and has as its object to provide an optical module that has a small number of parts and can reduce man-hours, thereby being excellent in economic efficiency.

  In order to achieve the above object, the present invention is an optical module including a cap holder into which a ferrule is inserted on one side, a transparent plate attached to a partition plate of the cap holder, and an optical semiconductor element.

  Specifically, the present invention provides a cylindrical cap holder into which a ferrule is inserted on one side, a partition plate having an opening in the center and partitioning the inside of the cap holder, and the cap holder in the opening. A transparent plate attached to the partition plate so as to close the other side of the cap, an optical semiconductor element positioned on the other side of the cap holder and disposed to face the transparent plate, and the optical semiconductor A stem that holds an element and is fixed to an end on the other side of the cap holder.

  By providing the cap holder in which the ferrule is inserted on the one side and the partition plate is formed, the optical module can be integrated with the ferrule holder and the stem holder according to the conventional optical module. Can be reduced. Moreover, if the cap holder is integrally formed, the optical module can reduce the manufacturing cost. Furthermore, the optical module does not require an expensive lens. Accordingly, the present invention can provide an optical module having a small number of parts and thereby being excellent in economic efficiency.

  In the present invention, the optical fiber further includes a ferrule having a shaft body in which an optical fiber is inserted through a central shaft and a metal sheath covering the outer periphery of the shaft body, and the ferrule is inserted into the one side of the cap holder. It is preferable.

  By inserting the ferrule on the one side of the cap holder, the optical module stably transmits light from or to the optical semiconductor element through the optical fiber inserted through the shaft body. I / O is possible. Therefore, the present invention can provide an optical module that operates stably.

  In the present invention, the dimensional tolerance of the inner diameter of the one side of the cap holder is 0 mm or more and +0.01 mm or less, and the dimensional tolerance of the outer diameter of the ferrule is −0.005 mm or more, It is preferably 0 mm or less.

  When the inner diameter of the one side of the cap holder and the outer diameter of the ferrule have the dimensional tolerances as described above, the optical module is inserted into the optical axis of the optical module when the ferrule is inserted. A vertical alignment step can be eliminated. Therefore, the present invention can reduce the number of man-hours, thereby providing an optical module that is excellent in economic efficiency.

  In this invention, it is preferable to further provide the contact part which the outer edge part of a ferrule end surface contact | abuts to the part which the surface by which the said transparent plate of the said partition plate is not mounted | worn, and the inner surface of the said cap holder contact.

  When the cap holder includes the contact portion, the optical module can eliminate the need for the alignment process in the optical axis direction of the optical module when inserting the ferrule. Therefore, the present invention can reduce the number of man-hours, thereby providing an optical module that is excellent in economic efficiency.

  In the present invention, it is preferable that the insertion hole on the one side of the cap holder is further provided with a cut.

  Since the cap holder has the notch, the optical module can identify the direction of inclination of the end face of the shaft body to the outside even when the ferrule is inserted on the one side of the cap holder. Can be made. Thus, the optical module can easily adjust the orientation of the ferrule. Therefore, the present invention can reduce the number of man-hours, thereby providing an optical module that is excellent in economic efficiency.

  In this invention, it is preferable that the said transparent plate is mounted | worn with the said partition plate so that it may become diagonal with respect to the surface perpendicular | vertical to the cylinder center axis | shaft of the said cap holder.

  By mounting the transparent plate on the partition plate so that the transparent plate is inclined, the optical module can reduce the incidence of light reflected by the transparent plate on the optical semiconductor element. Therefore, the present invention can provide an optical module that operates stably.

  The present invention can provide an optical module with a small number of parts and reduced man-hours, and thereby excellent in economic efficiency.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In addition, this invention is not limited to embodiment shown below.

(Embodiment 1)
In this embodiment, a cylindrical cap holder into which a ferrule is inserted on one side, a partition plate having an opening in the center and partitioning the inside of the cap holder, and the other side of the cap holder in the opening A transparent plate mounted on the partition plate so as to cover the optical plate, an optical semiconductor element positioned on the other side of the cap holder and disposed to face the transparent plate, and holding the optical semiconductor device And a stem fixed to the other end of the cap holder.

  The optical module 10 according to this embodiment will be described with reference to FIG. FIG. 1 is a cross-sectional view of the optical module 10. The optical module 10 includes a stem 23, an avalanche photodiode 25, a cap holder 26, a partition plate 27, a transparent plate 28, and a low melting point glass 29.

  The manufacture of the optical module 10 will be described. The cap holder 26 has a cylindrical shape, a rectangular tube shape, or other cylindrical shapes. The ferrule 22 is inserted into one side of the cap holder 26. The partition plate 27 is formed so that the inside of the cap holder 26 is partitioned by the partition plate 27. The partition plate 27 has an opening at the center.

  For example, the cap holder 26 may be integrally formed using a metal or plastic as a material. If the material of the cap holder 26 is a metal, the cap holder 26 may be formed by cutting and polishing. Further, if the material of the cap holder 26 is plastic, the cap holder 26 may be formed by injection molding or mold molding.

  Moreover, the part in which the ferrule 22 of the cap holder 26 is inserted and the part that accommodates the partition plate 27 and the stem 23 may be individually manufactured as parts. The cap holder 26 may be manufactured by combining the components described above.

  The transparent plate 28 is attached to the partition plate 27 so as to close the opening of the cap holder 26 on the side where the ferrule 22 is not inserted. For example, the transparent plate 28 may be a plate made of glass, ceramic, plastic, or resin that transmits desired light.

  If the material of the cap holder 26 is a metal and the material of the transparent plate 28 is glass or ceramic, the transparent plate 28 may be attached to the partition plate 27 using a low melting point glass 29.

  For example, the low melting point glass 29 that has been heated and turned into a liquid may be attached to the side surface of the transparent plate 28 and the surface of the partition plate 27. When the low melting point glass 29 is cooled, the low melting point glass 29 is solidified, so that the transparent plate 28 is fixed to the partition plate 27. Since the low melting point glass 29 has high confidentiality, the optical module 10 can maintain airtightness on the side of the cap holder 26 where the ferrule 22 is not inserted.

  Further, the transparent plate 28 may be fixed to the partition plate 27 by performing integral molding and press fitting (not shown in FIG. 1). When the transparent plate 28 is fixed by integral molding and press-fitting, the optical module 10 can maintain airtightness on the side of the cap holder 26 where the ferrule 22 is not inserted.

  Alternatively, the transparent plate 28 may be bonded to the partition plate 27 using an adhesive (not shown in FIG. 1). When the transparent plate 28 is bonded to the partition plate 27 using an adhesive, the optical module 10 may not be able to maintain the airtightness of the cap holder 26 on the side where the ferrule 22 is not inserted.

  The avalanche photodiode 25 is disposed on the stem 23 so as to face the transparent plate 28. For example, examples of the optical semiconductor element include an avalanche photodiode 25, a photodiode, a phototransistor, and other light receiving elements, or a light emitting diode, a laser diode, and other light emitting elements. The optical module 10 may include both a light receiving element and a light emitting element as an optical semiconductor element.

  The cap holder 26 is attached to the stem 23. For example, if the material of the cap holder 26 is a metal, the cap holder 26 may be attached to the stem 23 using the resistance welding described above. Further, if the material of the cap holder 26 is plastic, the cap holder 26 may be bonded to the stem 23.

  The point that the optical module 10 has a small number of parts and is excellent in economy will be described. The optical module 10 has a cylindrical shape on one side into which the ferrule 22 is inserted, and includes a cap holder 26 in which a partition plate 27 is formed. Therefore, since the ferrule holder 80 and the stem holder 81 as shown in FIG. 6 can be integrated, the optical module 10 can reduce the number of parts. Moreover, if the cap holder 26 is integrally formed, the optical module 10 can reduce the manufacturing cost. Furthermore, the optical module 10 does not require an expensive lens. Therefore, the present embodiment can provide an optical module having a small number of components and thereby being excellent in economic efficiency.

  Further, the optical module 10 may be arranged on the bottom surface of the stem 23 without arranging a stem lead (not shown in FIG. 1) on the side surface of the stem 23. Then, the optical module 10 becomes small.

  In the present invention, the optical fiber further includes a ferrule having a shaft body in which an optical fiber is inserted through a central shaft and a metal sheath covering the outer periphery of the shaft body, and the ferrule is inserted into the one side of the cap holder. It is preferable.

  The optical module 10 including the ferrule 22 will be described with reference to FIG. FIG. 2 is a cross-sectional view of the optical module 10 including the ferrule 22. The optical module 10 includes an optical fiber 21, a ferrule 22, a stem 23, an avalanche photodiode 25, a cap holder 26, a partition plate 27, a transparent plate 28, a low melting point glass 29, a shaft body 33 and a sheath body 34.

  The shaft body 33 has the optical fiber 21 inserted through the central axis. For example, the material of the shaft 33 can be zirconia, alumina, other ceramics, or hardened plastic.

  The outer periphery of the shaft 33 is covered with a metal sheath 34. The ferrule 22 includes a shaft body 33 and a sheath body 34 that covers the outer periphery of the shaft body 33. For example, the material of the sheath body 34 can include lead, iron, aluminum, titanium, silver, and other metals.

  The ferrule part of the SC type optical connector (JIS C5973) with a standardized diameter may be used as the shaft body 33, and the shaft body 33 may be covered with a metal sheath body 34 to form the ferrule 22 according to the present embodiment.

  By inserting the ferrule 22 on one side of the cap holder 26, the optical module 10 can stably input light to the avalanche photodiode 25 through the optical fiber 21 inserted through the shaft body 33. Therefore, this embodiment can provide an optical module that operates stably.

  In this embodiment, the dimensional tolerance of the inner diameter of the one side of the cap holder is 0 mm or more and +0.01 mm or less, and the dimensional tolerance of the outer diameter of the ferrule is −0.005 mm or more. , Preferably 0 mm or less.

  The cap holder 26 may be formed such that the dimensional tolerance of the inner diameter of one side of the cap holder 26 where the ferrule 22 is inserted is 0 millimeter or more and +0.01 millimeter or less. Further, the ferrule 22 may be formed so that the dimensional tolerance of the outer diameter of the ferrule 22 is not less than −0.005 millimeters and not more than 0 millimeters. The optical module 10 is perpendicular to the optical axis of the optical module 10 because the inner diameter on one side of the cap holder 26 where the ferrule 22 is inserted and the outer diameter of the ferrule 22 have the dimensional tolerances as described above. This alignment process can be eliminated. Therefore, this embodiment can reduce a man-hour, and can provide the optical module excellent in economical efficiency by this.

  In this embodiment, it is preferable to further include a contact portion where an outer edge portion of the ferrule end surface abuts on a portion where the surface of the partition plate on which the transparent plate is not mounted and the inner surface of the cap holder.

  The optical module 11 having the contact portion will be described with reference to FIG. FIG. 3 is a cross-sectional view of the optical module 11. The optical module 11 includes an optical fiber 21, a ferrule 22, a stem 23, an avalanche photodiode 25, a cap holder 26, a partition plate 27, a transparent plate 28, a low melting point glass 29, a contact portion 30, a shaft body 33 and a sheath body 34. .

  The abutting portion 30 is formed at a portion where the surface of the partition plate 27 on which the transparent plate 28 is not attached and the inner surface of the cap holder 26 are in contact with each other. The contact portion 30 may be formed so that the ferrule 22 is held at a position where the avalanche photodiode 25 can receive light output from the optical fiber 21 with the highest sensitivity.

  For example, the contact portion 30 may be integrally formed with the cap holder 26. Further, the contact portion 30 may be mounted on the cap holder 26 after being individually manufactured as a component.

  By inserting the ferrule 22 into the cap holder 26 so that the outer edge portion of the end face of the ferrule 22 abuts against the contact portion 30, the optical module 11 does not require the alignment process in the optical axis direction of the optical module 11 Can be. Therefore, this embodiment can reduce a man-hour, and can provide the optical module excellent in economical efficiency by this.

  In this embodiment, it is preferable that the insertion hole on the one side of the cap holder is further provided with a cut.

  The optical module 11 having notches will be described with reference to FIGS. 4 (a) and 4 (b). FIG. 4A is a top view of one side where the ferrule 22 of the cap holder 26 of the optical module 11 is inserted. FIG. 4A shows the optical fiber 21, the cap holder 26, the protrusion 32, the shaft body 33, and the sheath body 34. FIG. 4B is an enlarged view of one side where the ferrule 22 of the cap holder 26 of the optical module 11 is inserted. FIG. 4B shows the optical fiber 21, ferrule 22, cap holder 26, notch 31, protrusion 32, shaft body 33 and sheath body 34.

  An incision 31 is provided in the insertion opening on one side of the cap holder 26 where the ferrule 22 is inserted. There is no particular limitation on the shape of the cut 31. For example, the cut 31 may have a U-shaped, V-shaped, semicircular, or quadrangular cross-sectional shape.

  The end face of the shaft 33 facing the transparent plate 28 may be formed so as to be oblique to the normal to the optical axis of the optical module 11. Further, a protrusion 32 that matches the notch 31 may be formed on the ferrule 22. For example, the protrusion 32 may be formed on the side where the angle formed by the end face formed obliquely of the shaft body 33 and the side surface of the shaft body 33 is the largest (see FIG. 4B). In addition, the protrusion 32 may be formed on the side where the angle formed between the end face formed obliquely of the shaft body 33 and the side surface of the shaft body 33 is the smallest (not shown in FIG. 4).

  The ferrule 22 may be inserted into the cap holder 26 so that the protrusion 32 of the ferrule 22 and the notch 31 of the cap holder 26 fit. Even in a state where the ferrule 22 is inserted into the cap holder 22, the optical module 11 can identify the direction of inclination of the end face of the shaft body 33 to the outside. Therefore, the optical module 11 can easily adjust the orientation of the ferrule 22. Therefore, this embodiment can reduce a man-hour, and can provide the optical module excellent in economical efficiency by this.

  In this embodiment, it is preferable that the transparent plate is attached to the partition plate so as to be inclined with respect to a plane perpendicular to the cylinder center axis of the cap holder.

  The optical module 12 including the transparent plate 28 mounted obliquely will be described with reference to FIG. FIG. 5 is a cross-sectional view of the optical module 12. The optical module 12 includes an optical fiber 21, a ferrule 22, a stem 23, an avalanche photodiode 25, a cap holder 26, a partition plate 27, a transparent plate 28, a low melting point glass 29, a contact portion 30, a shaft body 33 and a sheath body 34. .

  In FIG. 5, the surface of the partition plate 27 on the side where the ferrule 22 of the cap holder 26 is not inserted is formed so as to be inclined with respect to a plane perpendicular to the cylinder center axis of the cap holder 26. The transparent plate 28 is mounted on the side of the partition plate 27 where the ferrule 22 is not inserted in the cap holder 26 so as to close the opening of the partition plate 27.

  Since the transparent plate 28 is inclined with respect to the optical axis of the optical module 12, the optical module 12 can reduce the incidence of light reflected by the transparent plate 28 on the avalanche photodiode 25. Therefore, this embodiment can provide an optical module that operates stably.

  The optical module of the present invention can be used as a receiving optical module, a transmitting optical module, and a single-core bidirectional optical module.

It is sectional drawing of the optical module which concerns on one Embodiment of this invention. It is sectional drawing of the optical module provided with the ferrule. It is sectional drawing of the optical module which concerns on one Embodiment of this invention. It is the upper side figure and enlarged view of the cap holder of the optical module which concerns on one Embodiment of this invention. It is sectional drawing of the optical module which concerns on one Embodiment of this invention. It is sectional drawing of the optical module which concerns on the conventional invention.

Explanation of symbols

10, 11, 12, 90 Optical module 21 Optical fiber 22 Ferrule 23 Stem 25 Avalanche photodiode 26 Cap holder 27 Partition plate 28 Transparent plate 29 Low melting point glass 30 Abutting portion 31 Notch 32 Projection 33 Shaft body 34 Sheath body 80 Ferrule holder 81 Stem holder 82 Lens 83 Stem cap 84 Stem lead

Claims (6)

A cylindrical cap holder into which a ferrule is inserted on one side;
A partition plate having an opening in the center and partitioning the inside of the cap holder;
A transparent plate attached to the partition plate so as to close the other side of the cap holder of the opening;
An optical semiconductor element located on the other side of the cap holder and arranged to face the transparent plate;
An optical module comprising: a stem that holds the optical semiconductor element and is fixed to an end on the other side of the cap holder.   It further comprises a ferrule having a shaft body through which an optical fiber is inserted through a central axis and a metal sheath covering the outer periphery of the shaft body, and the ferrule is inserted into the one side of the cap holder, The optical module according to claim 1.   The dimensional tolerance of the inner diameter of the one side of the cap holder is 0 mm or more and +0.01 mm or less, and the dimensional tolerance of the outer diameter of the ferrule is −0.005 mm or more and 0 mm or less. The optical module according to claim 2, wherein the optical module is provided.   The contact part which the outer edge part of a ferrule end surface contact | abuts to the part which the surface by which the said transparent plate of the said partition plate is not mounted | worn, and the inner surface of the said cap holder contact is further provided. An optical module according to any one of the above.   The optical module according to claim 1, further comprising a cut in the insertion port on the one side of the cap holder.   6. The optical module according to claim 1, wherein the transparent plate is attached to the partition plate so as to be inclined with respect to a plane perpendicular to the cylinder center axis of the cap holder.

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