Optical connector and a method of attaching the same

• US 6,193,421 B1
• Filed: 08/25/1999
• Issued: 02/27/2001
• Est. Priority Date: 10/09/1996
• Status: Expired due to Term

• Current Assignee: Nippon Telegraph and Telephone Corporation, Sumitomo Electric Industries Limited (Sumitomo Corporation)
• Original Assignee: Nippon Telegraph and Telephone Corporation, Sumitomo Electric Industries Limited (Sumitomo Corporation)
• Inventors: Furukawa, Shin-ichi, Tamekuni, Yoshikyo, Hogari, Kazuo, Ueda, Tomohiko
• Primary Examiner(s): NGO, HUNG NHAT
• Application Number:
  US09/382,780
• Time in Patent Office: 552 Days
• Field of Search: 385/85, 385/68, 385/65, 385/137, 385/83, 385/62, 385/81
• US Class Current: 385/65
• CPC Class Codes: G02B 6/3636 the mechanical coupling means being grooves G02B6/3652 takes precedence
• CPC Class Codes: G02B 6/3644 the coupling means being through-holes or wall apertures
• CPC Class Codes: G02B 6/3652 the additional structures being prepositioning mounting areas, allowing only movement in one dimension, e.g. grooves, trenches or vias in the microbench surface, i.e. self aligning supporting carriers
• CPC Class Codes: G02B 6/3806 Semi-permanent connections, i.e. wherein the mechanical means keeping the fibres aligned allow for removal of the fibres dismountable connectors G02B6/3807
• CPC Class Codes: G02B 6/3838 using grooves for light guides
• CPC Class Codes: G02B 6/3846 with fibre stubs

Abstract

A short optical fiber 2 is incorporated in a ferrule 1 having a polished front end, so as to be projected from the rear end of the ferrule. In a base member 3 in which the short optical fiber is to be fitted into a hole 3b, a V-groove 3d to which the glass portion of an optical fiber is to be fixed, and a V-groove 3e to which the coated portion is to be fixed are formed. A cover member 4 is placed on the base member. The base member 3 and the cover member 4 are clamped by clamp members 5a and 5b and the base member 3 presses to V-grooves. Wedges which are not shown are pressingly inserted between recessed 3g and 4c, and 3h and 4d, and an optical fiber 10 is inserted from the rear portion. Thereafter, the wedges are detached and the optical connector is attached to the terminal of the optical fiber 10.

Claims

1. An optical connector comprising:

a ferrule which incorporates a short optical fiber in a small bore which is formed along a center axis, said short optical fiber being projected from a rear end of said ferrule, said ferrule having a polished front end face;

a base member having (A) a holding portion which holds said rear end of said ferrule and (B) an optical fiber positioning and fixing groove which is formed in an upper face to be continuous with said small bore;

a cover member constructed and arranged to press an optical fiber against said optical fiber positioning and fixing groove; and

a clamp member constructed and arranged to press said cover member toward said base member,

wherein an outer periphery of a rear end face of said short optical fiber is chamfered.

2. An optical connector according to claim 1, further comprising:

a wedge insertion portion constructed and arranged to receive a wedge for pressingly separating said cover member and said base member from each other.

3. An optical connector according to claim 2, wherein a size of the chamfer of said short optical fiber is not smaller than 10 μ

m.

4. An optical connector according to claim 2, wherein a work of chamfering said short optical fiber is conducted by an electric discharge.

5. An optical connector according to claim 2,

wherein, during an assembly of said optical connector, a cylindrical member is disposed so as to be (C) continuous with a rear end of said short optical fiber and (D) above said optical fiber positioning and fixing groove, an outer diameter of said cylindrical member being substantially equal to an outer diameter of said short optical fiber.

6. An optical connector according to claim 2, wherein said cylindrical member is a silica optical fiber.

7. An optical connector according to claim 2,

wherein, during an assembly of said optical connector, a dummy member is pressingly held between said cover member and said base member, thereby preventing said cover member and said base member from substantially applying a pressing force on said short optical fiber.

8. An optical connector according to claim 1, wherein a size of the chamfer of said short optical fiber is not smaller than 10 μ

m.

9. An optical connector according to claim 1, wherein a work of chamfering said short optical fiber is conducted by an electric discharge.

10. A method of attaching an optical connector, said optical connector comprising:

a ferrule which incorporates a short optical fiber in a small bore which is formed along a center axis, said short optical fiber being projected from a rear end of said ferrule, said ferrule having a polished front end face;

a base member having (A) a holding portion which holds said rear end of said ferrule and (B) an optical fiber positioning and fixing groove which is formed in an upper face to be continuous with said small bore;

a cover member constructed and arranged to press an optical fiber against said optical fiber positioning and fixing groove;

a clamp member constructed and arranged to press said cover member toward said base member; and

a wedge insertion portion constructed and arranged to receive a wedge for pressingly separating said cover member and said base member from each other,

wherein an outer periphery of a rear end face of said short optical fiber is chamfered, and

wherein, during an assembly of said optical connector, a cylindrical member is disposed so as to be (C) continuous with a rear end of said short optical fiber and (D) above said optical fiber positioning and fixing groove, an outer diameter of said cylindrical member being substantially equal to an outer diameter of said short optical fiber,

said method comprising;

removing said cylindrical member, said removing including inserting said wedge into said wedge insertion portion;

inserting the optical fiber from a rear side of said optical connector into a space between said base member and said cover member, said space being formed by said inserting said wedge, said inserting the optical fiber continuing until the optical fiber abuts against said short fiber; and

removing said wedge to attach said optical connector to a terminal of the optical fiber.

11. A method of attaching an optical connector, said optical connector comprising:

a ferrule which incorporates a short optical fiber in a small bore which is formed along a center axis, said short optical fiber being projected from a rear end of said ferrule, said ferrule having a polished front end face;

a base member having (A) a holding portion which holds said rear end of said ferrule and (B) an optical fiber positioning and fixing groove which is formed in an upper face to be continuous with said small bore;

a cover member constructed and arranged to press an optical fiber against said optical fiber positioning and fixing groove;

a clamp member constructed and arranged to press said cover member toward said base member; and

a wedge insertion portion constructed and arranged to receive a wedge for pressingly separating said cover member and said base member from each other,

wherein an outer periphery of a rear end face of said short optical fiber is chamfered, and

wherein, during an assembly of said optical connector, a dummy member is pressingly held between said cover member and said base member, thereby preventing said cover member and said base member from substantially applying a pressing force on said short optical fiber,

said method comprising;

removing said dummy member;

inserting said wedge into said wedge insertion portion;

inserting the optical fiber from a rear side of said optical connector into a space between said base member and said cover member, said space being formed by said inserting said wedge, said inserting the optical fiber continuing until the optical fiber abuts against said short optical fiber; and

removing said wedge to attach said optical connector to a terminal to the optical fiber.

12. A method of attaching an optical connector, said optical connector comprising:

a ferrule which incorporates a short optical fiber in a small bore which is formed along a center axis, said short optical fiber being projected from a rear end of said ferrule, said ferrule having a polished front end face;

a base member having (A) a holding portion which holds said rear end of said ferrule and (B) an optical fiber positioning and fixing groove which is formed in an upper face to be continuous with said small bore;

a cover member constructed and arranged to press an optical fiber against said optical fiber positioning and fixing groove;

a clamp member constructed and arranged to press said cover member toward said base member; and

a wedge insertion portion constructed and arranged to receive a wedge for pressingly separating said cover member and said base member from each other,

wherein an outer periphery of a rear end face of said short optical fiber is chamfered,

said method comprising;

holding a dummy member between said cover member and said base member;

inserting the optical fiber from a rear side of said optical connector into a space between said base member and said cover member, said space being formed by said holding said dummy member, said inserting the optical fiber continuing until the optical fiber abuts against said short optical fiber; and

removing said dummy member to attach said optical connector to a terminal of the optical fiber.