Sensitivity-enhanced ultrafast optical tomography by parametric- and Raman-amplified temporal imaging.

To overcome the speed limitation of conventional optical tomography, a temporal imaging technique has been integrated with optical time-domain reflectometry to realize ultrafast temporally magnified (TM) tomography. In this Letter, the sensitivity of TM tomography has been further enhanced using optical parametric amplification and distributed Raman amplification, and this technique is named temporally encoded amplified and magnified (TEAM) tomography. As a result, a 78-dB sensitivity has been realized, comparable to ultrafast optical coherence tomography systems. In addition, an 86.7-mu m axial resolution can be realized across a 67.5-mm imaging range. To demonstrate the significance of sensitivity improvement, tomographic imaging of a centimeter-thick phantom is provided at an A-scan rate of 44 MHz. (C) 2018 Optical Society of America