光相関領域計測のための外部変調方式の提案に関する野田(M1)の論文が Applied Physics Express に掲載されました。

K. Noda, G. Han, H. Lee, Y. Mizuno, and K. Nakamura, “Proposal of external modulation scheme for fiber-optic correlation-domain distributed sensing,” Appl. Phys. Express, vol. 12, no. 2, 022005 (2019).

All the previous configurations of optical correlation-domain reflectometry (OCDR) have been based on the direct modulation of laser driving current. However, some lasers are not designed for high-speed large-amplitude modulation, and the modulation amplitude and frequency are mutually dependent. In this work, to mitigate these drawbacks, we propose an external modulation scheme for OCDR. After confirming its basic operation, we show that a non-specially designed laser can be employed. We also clarify that the interdependence of the modulation amplitude and frequency is negligibly small in this scheme, which is not the case for the conventional direct modulation scheme.