| 摘要 |
PROBLEM TO BE SOLVED: To accurately measure an optical pulse waveform by converting an optical pulse signal led to a superconductive part in a Josephson sampling measurement circuit through an optical cable into an electric pulse and leading the electric pulse to a superconductivity light conductive element connected to the superconductive part in the measurement circuit. SOLUTION: On a superconductive part 10 tip, a trigger signal Itp is added to a pulse generating circuit 22, while a trigger signal Itu is added to an optical pulse generating device 13. An optical pulse complying with the trigger signal Itu is led through an optical fiber 51 so as to be applied to a light conductive element 52 and converted into an electric pulse signal Iu, which is added to a sampling gate 12. On the other hand, a very short pulse signal Ip generated from the pulse generating circuit 22 by the trigger signal Itp is added to the sampling gate 12. In addition, a bias current Is from a bias control circuit 30 is superimposed and added to the sampling gate 12, and a time difference between the trigger pulses Itu, Itp is varied at minute time intervals, and consequently, a sampling value for the optical pulse is provided.
|
