Optical loop-back attenuator

• US 20030123838A1
• Filed: 12/27/2001
• Published: 07/03/2003
• Est. Priority Date: 10/31/2001
• Status: Active Grant

• Current Assignee: Google LLC (Alphabet Inc.)
• Original Assignee: Hon Hai Precision Industry Co., Ltd.
• Inventors: Chang, Yao-Hao, Wang, Chung-Chih
• Granted Patent: US 6,707,979 B2
• Time in Patent Office: Days
• US Class Current: 385/140
• CPC Class Codes: G02B 6/266 the optical element being an attenuator
• CPC Class Codes: G02B 6/3827 Wrap-back connectors, i.e. containing a fibre having an U shape
• CPC Class Codes: G02B 6/3897 Connectors fixed to housings, casing, frames or circuit boards G02B6/44528 takes precedence

Abstract

An optical loop-back attenuator (2) includes a frame (22), a cover (21) attached to the frame, an optical fiber (24), an optical fiber fixture (23) retaining and fixing the optical fiber, and two SC plug connectors (25) receiving and retaining opposite ends of the optical fiber therein. The frame and the cover cooperate to fittingly receive the optical fiber, the optical fiber fixture and portions of the SC plug connectors therein. The optical fiber has a bent part (242) which is configured to be semicircular or to have another suitable shape that achieves a desired attenuation.

Claims

1. An optical attenuator comprising:

an optical fiber comprising an attenuating part which is bent to obtain a desired attenuation; and

a fixture fixing the optical fiber thereto.

2. The optical attenuator as described in claim 1, further comprising two optical connectors respectively aligned with opposite ends of the optical fiber.

3. The optical attenuator as described in claim 2, wherein each of the optical connectors is a subscriber connector plug connector.

4. The optical attenuator as described in claim 2, wherein the optical connectors are engaged in the fixture.

5. The optical attenuator as described in claim 1, wherein the optical fiber at the attenuating part thereof is fixed to the fixture with adhesive.

6. The optical attenuator as described in claim 1, wherein the attenuating part of the optical fiber is configured to be generally semicircular.

7. The optical attenuator as described in claim 1, wherein the attenuating part of the optical fiber is configured to be generally coiled.

8. The optical attenuator as described in claim 4, wherein the fixture comprises two holders engaged with the optical connectors respectively.

9. The optical attenuator as described in claim 1, wherein the fixture defines two grooves retaining corresponding parts of the optical fiber respectively.

10. The optical attenuator as described in claim 1, further comprising a package encasing the attenuator therein.

11. The optical attenuator as described in claim 10, wherein the package comprises a frame and a cover.

12. An optical attenuator comprising:

an optical fiber comprising an attenuating part;

a fixture fixing the optical fiber thereto; and

two optical connectors respectively aligned with opposite ends of the optical fiber;

wherein the attenuating part of the optical fiber is bent such that a desired attenuation is obtained.

13. The optical attenuator as described in claim 12, wherein each of the optical connectors is a subscriber connector plug connector.

14. The optical attenuator as described in claim 12, wherein the optical connectors are engaged in the fixture.

15. The optical attenuator as described in claim 12, wherein the optical fiber at the attenuating part thereof is fixed to the fixture with adhesive.

16. The optical attenuator as described in claim 12, wherein the attenuating part of the optical fiber is configured to be generally semicircular.

17. The optical attenuator as described in claim 12, wherein the attenuating part of the optical fiber is configured to be generally coiled.

18. The optical attenuator as described in claim 12, wherein the fixture comprises two holders engaged with the optical connectors respectively.

19. The optical attenuator as described in claim 12, wherein the fixture defines two grooves retaining corresponding parts of the optical fiber respectively.

20. A method of making an attenuator comprising the steps of:

providing a pair of juxtaposed fiber connectors with mating ports facing to a same direction;

connecting rear ends of said pair of connectors with an optical fiber;

securing the fiber in position around two opposite end portions thereof;

forming a curved portion between said two end portions;

adjusting radii or turns of said curved portion for obtaining a desired attenuation value; and

fixing said curved portion in position.