| 摘要 |
<p>A differential laser Doppler velocimeter is based on the use of a modified fibre optic Sagnac interferometer (1, 2). The interferometer phase is dependent not on the target displacement, but on its velocity. The output intensity of the interferometer may be modulated by control means (PC) which controls loop birefringence introducing a phase bias and polarisation offset between counter-propagating beams.</p> |
