The spatial light receiver and its coupling characteristics

The effective couple of the space light into the optical fiber is the key point of the free-space optical communication. In order to solve this problem, the novel tapered optical fiber head is proposed. The special tapered structure could improve coupling efficiency through expanding the light receiving area. In order to study its coupling characteristics, the longitudinal propagation constant of the connector is expanded by Taylor series according to the wave theory. And the approximate solution of the power distribution is obtained. Then, the coupling efficiency measurement experiment with the tapered connectors and the conmmon connector is finished. The experimental result is consistent with the theoretical analysis basically. This work provides a theoretical reference for the design of the new tapered connector, which could be adopted in the free-space optical communication.