Kim Tae Shik, Vakoc Benjamin J
Harvard Medical School, Boston, Massachusetts 02115, USA.
Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, Massachusetts 02114, USA.
Biomed Opt Express. 2020 Jun 8;11(7):3534-3542. doi: 10.1364/BOE.392359. eCollection 2020 Jul 1.
Circular-ranging (CR) optical coherence tomography (OCT) uses frequency comb sources to improve long-range imaging. While the initial development of CR-OCT focused on extremely high-speed imaging (i.e., operation at A-line rates of several to tens of MHz), there are many applications and imaging strategies for which more moderate speeds are preferred. However, we lack suitable frequency comb sources to enable moderate speed CR-OCT imaging. Here, we describe a novel phase-code mode-locking (PCML) laser architecture that can be operated from the kilohertz to megahertz range, while also offering novel features such as dynamic re-configurability and simplified linear-in-time frequency stepping. We demonstrate a prototype CR-OCT system with a PCML laser and present imaging results at A-line rates from 176 kHz to 3.52 MHz with coherence-length limited imaging depths as high as 170 mm.
环形扫描（CR）光学相干断层扫描（OCT）使用频率梳源来改善长距离成像。虽然CR-OCT的最初发展集中在极高速成像（即A线速率为几兆赫兹到几十兆赫兹的操作），但有许多应用和成像策略更倾向于中等速度。然而，我们缺乏合适的频率梳源来实现中等速度的CR-OCT成像。在此，我们描述了一种新型的相位编码锁模（PCML）激光架构，它可以在千赫兹到兆赫兹范围内运行，同时还具有动态可重新配置和简化的线性时间频率步进等新特性。我们展示了一个带有PCML激光的CR-OCT系统原型，并给出了A线速率从176 kHz到3.52 MHz的成像结果，相干长度限制下的成像深度高达170 mm。
