Song Hoseong, Cho Seung Bum, Kim Dong Uk, Jeong Sungho, Kim Dug Young
School of Information and Mechatronics, Gwangju Institute of Science and Technology, 261 Cheomdan-gwagiro, Buk-gu, Gwangju 500-712, South Korea.
Appl Opt. 2011 Jul 20;50(21):4000-4. doi: 10.1364/AO.50.004000.
We demonstrate an ultra-high-speed phase-sensitive time-wavelength-domain optical coherence reflectometer with a stretched pulse supercontinuum source. A pulsed fiber laser operating at 10 MHz repetition rate was used to generate a pulsed supercontinuum of 30 ps pulse duration by using a nonlinear optical fiber. The supercontinuum pulses are stretched into 70 ns pulses with a highly dispersive fiber. With this stretched pulse source, we have built a phase-sensitive optical coherence reflectometer that measures the spectral interferogram of reflected light. By using the linear relation between the wavelength and the temporal position in a linearly chirped pulse, ultra-high-speed spectrum measurement can be obtained with this method in the time domain. We have demonstrated ultra-high-speed two-dimensional surface profiling for a standard image target and high-speed single-point monitoring for a fixed point under vibrational motion. It is shown that the measurement speed for the position of a single point can be as fast as 2.5 MHz, while the position accuracy can be better than 4.49 nm.
我们展示了一种采用拉伸脉冲超连续谱源的超高速相敏时间-波长域光学相干反射仪。使用一台重复频率为10 MHz的脉冲光纤激光器，通过非线性光纤产生脉宽为30 ps的脉冲超连续谱。超连续谱脉冲通过高色散光纤被拉伸为70 ns的脉冲。利用这个拉伸脉冲源，我们构建了一台相敏光学相干反射仪，用于测量反射光的光谱干涉图。通过利用线性啁啾脉冲中波长与时间位置之间的线性关系，该方法可在时域中实现超高速光谱测量。我们展示了针对标准图像目标的超高速二维表面轮廓测量以及针对振动运动下固定点的高速单点监测。结果表明，单点位置的测量速度可达2.5 MHz，而位置精度优于4.49 nm。
