A method and apparatus for monitoring the optical power output of a VCSEL uses refracted ray coupling to direct rays refracted out of an optical transmission medium, towards a photodetector. The photodetector is coupled to feedback circuitry and laser control circuitry capable of adjusting the VCSEL based on the monitored power output. A portion of the rays that enter the optical fiber are refracted out of the optical fiber by means of high-index materials and directed toward the photodetector by reflective surfaces situated around the coupling region in which the VCSEL is coupled to the optical fiber.

VCSEL monitoring using refracted ray coupling

The invention discloses an optical fiber reflector based on a deep hole ceramic packaging structure. The optical fiber reflector comprises seven parts, i.e. an optical fiber, an epoxy glue adhesive, a ceramic insertion core, a reflecting film, a tube, a packaging adhesive and tail fiber protection silicon rubber, wherein the diameter range of a tight casing outside an optical fiber coating layer is 500 microns-900 microns; a fiber guide groove of the ceramic insertion core comprises a sleeve with the length of 2 mm-3.5 mm; an optical fiber stripping fracture is located in the fiber guide groove of the ceramic insertion core and is fixed on the ceramic insertion core by using the epoxy glue adhesive; the reflecting film is directly evaporated on a polishing end face formed by the ceramic insertion core, the epoxy glue adhesive and the optical fiber together; the tube is sleeved outside the ceramic insertion core of the optical fiber reflector and is adhered and fixed by using the packaging adhesive, and the packaging adhesive fills gaps among the inner wall of the hollow tube, one end of the fiber guide groove of the ceramic insertion core and the outer wall of the optical fiber close to the ceramic insertion core; the tail fiber protection silicon rubber is coated at the root of the optical fiber of the optical fiber reflector so as to cover an end face formed by the tube and the packaging adhesive together.

Optical fiber reflector based on deep hole ceramic packaging structure

A connector for optical fibres, in particular single mode fibres is proposed, comprising a connector pin which is fixedly secured to the fibre and a coupling sleeve which interconnects the two connector pins. To allow damaged connector portions to be replaced at low cost, three successive connectors (8,3,9) are provided for interconnecting two fibres (1,2) having a great length of several hundred meters, the two outer connectors (8,9) being connected with one connector pin (11,14 respectively) to one end of the two fibres (1,2 respectively) and the central connector (3) being connected to the other connector pin (12,13 respectively) of each of the outer connectors (8,9 respectively). Said fibre connection (7) can be interrupted by disconnecting the central connector members (3).

Connector for optical fibres

A plug connector for optical waveguides, especially for single mode optical fibers, comprises a male contact fixedly attached to each optical fiber and a coupling sleeve that connects the two male contacts. In order to replace economically damaged portions of the connector, three plug connectors (8, 3, 9) arranged directly one behind the other are used to connect two optical fibers (1, 2) having several hundred meters in length. Both plug connectors (8, 9) outside are connected by means of a male contact (11 or 14) each at one end of two optical fibers (1, 2) and the intermediate plug connector (3) is connected to the other male contact (12 or 13) of the two plug connectors (8 or 9) outside. To undo (7) connecting between the optical fibers it is sufficient to detach the plug connector (3) intermediate.

Plug-type connector for beam waveguides.

An optical fibre reflectometer in which the end of the optical fibre 4-port coupler for optical coupling to test fibres is not protected from damage by the use of a sapphire window because of the problems of unwanted reflections that this engenders. Instead the end is coupled to the test fibres by means of a replaceable slug (33) containing a stub length of fibre (20). This fibre stub (20) is intrinsically just as susceptible to cumulative damage when test fibres are repeatedly butted against its end, but it protects the coupler because it is itself butted against the coupler only once in its life. When the cumulative damage becomes excessive the slug can be replaced more simply and cheaply than replacing the whole coupler.

David Howard Forbes

Papers

Optical fibre reflectometer