JP-7856570-B2 - Optical connection structure

Inventors

• 矢加部 祥
• 木村 元佳

Assignees

• 住友電気工業株式会社
• 日本通信電材株式会社

Dates

Publication Date

20260511

Application Date

20210917

Priority Date

20200925

Claims (15)

1. The first ferrule and, The second ferrule and, A first housing for housing the first ferrule, The device comprises an adapter capable of housing the first ferrule and the second ferrule inside, The first ferrule has a tip portion located at the end in a first direction, which is the direction in which the first ferrule is inserted into and removed from the adapter, and having a first light inlet/outlet portion formed thereon; first and second sides facing each other in a second direction intersecting the first direction; and a flange portion provided on the side opposite to the tip portion in the first direction, with a width in the second direction that is wider than that of the tip portion. The second ferrule has a tip portion located at the front in the first direction and having a second light inlet/outlet portion formed thereon, and a first side surface and a second side surface facing each other in the second direction, The first side surface of the first ferrule and the first side surface of the second ferrule are provided with a first recess or first protrusion extending along the first direction, and the second side surface of the first ferrule and the second side surface of the second ferrule are provided with a second recess or second protrusion extending along the first direction. The inner surface of the adapter is provided with a third protrusion that can be fitted into the first recess of both the first ferrule and the second ferrule, or a third recess that can be fitted into the first protrusion of both the first ferrule and the second ferrule, and a fourth protrusion that can be fitted into the second recess of both the first ferrule and the second ferrule, or a fourth recess that can be fitted into the second protrusion of both the first ferrule and the second ferrule. The first ferrule and the second ferrule are fitted into the adapter such that when the first recess or first protrusion of both the first ferrule and the second ferrule are fitted into the third protrusion or third recess of the adapter, and the second recess or second protrusion of both the first ferrule and the second ferrule are fitted into the fourth protrusion or fourth recess of the adapter, the tip of the first ferrule and the tip of the second ferrule face each other at a predetermined distance apart within the adapter, thereby optically connecting the first light input/output section and the second light input/output section. At least a portion of the first ferrule, the second ferrule, and the adapter is provided with a positioning structure for positioning the tip of the first ferrule and the tip of the second ferrule facing each other at a predetermined distance apart, and the flange of the first ferrule functions as part of the positioning structure for indirectly positioning the first ferrule relative to the adapter. The first housing is configured such that its movement along the first direction relative to the adapter is restricted, and the movement of the first ferrule along the first direction relative to the first housing is restricted by the flange of the first ferrule, thereby positioning the first ferrule relative to the adapter. Optical connection structure.
2. The predetermined distance at which the tip of the first ferrule and the tip of the second ferrule are separated and facing each other when the first light input/output section and the second light input/output section are optically connected is 0.05 mm or more and 2.0 mm or less. The optical connection structure according to claim 1.
3. The distance from one end of the flange portion of the first ferrule to the tip portion is 2 mm or more and 10 mm or less. The optical connection structure according to claim 1 or claim 2.
4. The invention further comprises a second housing for housing the aforementioned second ferrule, The second ferrule is provided on the side opposite to the tip in the first direction and further has a flange portion that is wider in the second direction than the tip. The flange portion of the second ferrule functions as part of the positioning structure that indirectly positions the second ferrule relative to the adapter. The second housing is configured such that its movement along the first direction relative to the adapter is restricted, and the movement of the second ferrule along the first direction relative to the second housing is restricted by the flange of the second ferrule, thereby positioning the second ferrule relative to the adapter. The optical connection structure according to any one of claims 1 to 3.
5. At least one of the first light input/output section and the second light input/output section is a lens array arranged along the second direction. The optical connection structure according to any one of claims 1 to 4.
6. The lens array is provided in a region recessed into the ferrule from the tip surface of the tip portion, and the tip of the lens array is located further inside the ferrule than the tip surface. The optical connection structure according to claim 5.
7. The lens array has a shape that protrudes from the tip surface of the tip portion to the outside of the ferrule. The optical connection structure according to claim 5.
8. At least one of the third protrusion or third recess and the fourth protrusion or fourth recess of the adapter is configured to be elastically deformable in the second direction. The optical connection structure according to any one of claims 1 to 7.
9. The first side surface of the first ferrule and the first side surface of the second ferrule are provided with a first recess extending along the first direction, and the second side surface of the first ferrule and the second side surface of the second ferrule are provided with a second recess extending along the first direction. The inner surface of the adapter is provided with a third protrusion that can be fitted into the first recess of both the first ferrule and the second ferrule, and a fourth protrusion that can be fitted into the second recess of both the first ferrule and the second ferrule. The first ferrule and the second ferrule are fitted into the adapter such that when the first recesses of both the first and second ferrules are fitted into the third protrusion of the adapter and the second recesses of both the first and second ferrules are fitted into the fourth protrusion of the adapter, the tip of the first ferrule and the tip of the second ferrule face each other at a predetermined distance apart within the adapter, thereby optically connecting the first light input/output section and the second light input/output section. The optical connection structure according to any one of claims 1 to 8.
10. The first housing has a pair of sides facing each other in the second direction, and a column extending in the second direction that connects the pair of sides together. The flange portion of the first ferrule abuts against the column portion, thereby restricting the movement of the first ferrule. The optical connection structure according to any one of claims 1 to 9.
11. The first housing has a pair of first sides facing each other in the second direction, and a first column extending in the second direction and connecting the pair of first sides together. The flange portion of the first ferrule abuts against the first column portion, thereby restricting the movement of the first ferrule. The second housing has a pair of second sides facing each other in the second direction, and a second column extending in the second direction and connecting the pair of second sides together. The flange portion of the second ferrule abuts against the second column portion of the second housing, thereby restricting the movement of the second ferrule. The optical connection structure according to claim 4 .
12. A first spring is provided, and the flange portion of the first ferrule is biased toward the second ferrule by the first spring. A second spring is provided, and the flange portion of the second ferrule is biased toward the first ferrule by the second spring. The optical connection structure according to claim 4 or claim 11 .
13. The movement of the first ferrule toward the second ferrule along the first direction relative to the first housing is restricted by the flange of the first ferrule. The optical connection structure according to any one of claims 1 to 12.
14. The first side surface of the first ferrule is provided with a first positioning portion and a second positioning portion, and a first stepped portion located between the first positioning portion and the second positioning portion. The second side surface of the first ferrule is provided with a third positioning portion and a fourth positioning portion, and a second stepped portion located between the third positioning portion and the fourth positioning portion. The first positioning portion and the second positioning portion are configured to contact the third protrusion or third recess of the adapter, while the first stepped portion is configured not to contact the third protrusion or third recess of the adapter. The third positioning portion and the fourth positioning portion are configured to contact the fourth protrusion or fourth recess of the adapter, while the second stepped portion is configured not to contact the fourth protrusion or fourth recess of the adapter. The optical connection structure according to any one of claims 1 to 13.
15. The first positioning portion and the second positioning portion are separated by a range of 3 mm to 10 mm in the first direction. The optical connection structure according to claim 14.

Description

This disclosure relates to an optical connection structure. This application claims priority under Japanese application No. 2020-161211, filed on 25 September 2020, and incorporates all the provisions contained in the said Japanese application. Patent Document 1 discloses a technique for aligning multi-core optical fibers using guide pins. In this technique, one end of a pair of guide pins is inserted into a pair of guide pin insertion holes provided on the tip surface of a ferrule, and the other end of a pair of guide pins is inserted into a pair of guide pin insertion holes provided on the tip surface of the ferrule to be connected. This aligns the multi-core optical fibers (i.e., aligns the multi-core optical fiber with the multi-core optical fiber to be connected). Japanese Patent Publication No. 2019-90974 This disclosure provides, in one aspect, an optical connection structure. This optical connection structure comprises a first ferrule, a second ferrule, and an adapter capable of housing the first ferrule and the second ferrule internally. The first ferrule has a tip portion located at the end in a first direction, which is the direction in which the first ferrule is inserted into and removed from the adapter, and having a first light input/output portion formed thereon, and a first side surface and a second side surface facing each other in a second direction intersecting the first direction. The second ferrule has a tip portion located at the end in the first direction, and having a second light input/output portion formed thereon, and a first side surface and a second side surface facing each other in the second direction. The first side surface of the first ferrule and the first side surface of the second ferrule are provided with a first recess or a first protrusion. The first recess or first protrusion extends along the first direction. The second side surface of the first ferrule and the second side surface of the second ferrule are provided with a second recess or a second protrusion. The second recess or second protrusion extends along the first direction. The inner surface of the adapter is provided with a third protrusion or a third recess that can be fitted into the first recess of both the first and second ferrules, and a fourth protrusion or a fourth recess that can be fitted into the second recess of both the first and second ferrules. The first and second ferrules are fitted into the adapter such that when the first recess or first protrusion of both the first and second ferrules is fitted into the third protrusion or third recess of the adapter and the second recess or second protrusion of both the first and second ferrules is fitted into the fourth protrusion or fourth recess of the adapter, the tip of the first ferrule and the tip of the second ferrule face each other at a predetermined distance within the adapter, thereby optically connecting the first light input/output section and the second light input/output section. Figure 1 is a perspective view showing an optical connector according to one embodiment.Figure 2 is a perspective view showing the ferrule of the optical connector shown in Figure 1.Figure 3 is a perspective view showing an optical connection structure in which a pair of optical connectors (ferrules) are optically connected within an adapter.Figure 4 is a side view of the optical connection structure shown in Figure 3.Figure 5 is a cross-sectional view of the optical connection structure shown in Figure 4.Figure 6 is a plan view showing a pair of optical connectors (ferrules) separated by a predetermined distance when optically connected within an adapter.Figure 7 is a schematic cross-sectional view showing an example of a light input/output section.Figure 8 is a schematic cross-sectional view showing another example of a light input/output section.Figure 9 is a perspective view showing the optical connection state in which a pair of optical connectors (ferrules) are optically connected within the adapter via the housing.Figure 10 is a cross-sectional view of an optical connection structure according to a modified example.Figure 11 is a cross-sectional view of an optical connection structure according to another modified example. [Issues this disclosure aims to address] When positioning multiple optical fibers using a guide pin and a ferrule provided with a guide pin insertion hole, as in the technology disclosed in Patent Document 1, the following problems may arise. For example, in order to position multiple optical fibers with high precision, a guide pin with high dimensional accuracy is required so that the clearance with the guide pin insertion hole is as small as possible. Furthermore, when cleaning the ferrule into which the guide pin is inserted, it may not be possible to completely remove foreign matter such as dust near the guide pin. In this case, such foreign matter may interfere, reducing the positioning accuracy of the multiple optical fibers and pot