Nose Keisuke, Ozeki Yasuyuki, Kishi Tatsuya, Sumimura Kazuhiko, Nishizawa Norihiko, Fukui Kiichi, Kanematsu Yasuo, Itoh Kazuyoshi
Division of Advanced Science and Biotechnology, Osaka University, Suita, Osaka 565-0871, Japan.
Opt Express. 2012 Jun 18;20(13):13958-65. doi: 10.1364/OE.20.013958.
We propose the collinear balanced detection (CBD) technique for noise suppression in fiber laser (FL)-based stimulated Raman scattering (SRS) microscopy. This technique reduces the effect of laser intensity noise at a specific frequency by means of pulse splitting and recombination with a time delay difference. We experimentally confirm that CBD can suppress the intensity noise of second harmonic (SH) of Er-FL pulses by 13 dB.The measured noise level including the thermal noise is higher by only ~1.4 dB than the shot noise limit. To demonstrate SRS imaging, we use 4-ps SH pulses and 3-ps Yb-FL pulses, which are synchronized subharmonically with a jitter of 227 fs. The effectiveness of the CBD technique is confirmed through SRS imaging of a cultured HeLa cell.
我们提出了共线平衡检测（CBD）技术，用于基于光纤激光器（FL）的受激拉曼散射（SRS）显微镜中的噪声抑制。该技术通过脉冲分裂和具有时间延迟差的重组来降低特定频率下激光强度噪声的影响。我们通过实验证实，CBD可以将铒光纤激光器（Er-FL）脉冲的二次谐波（SH）强度噪声抑制13 dB。包括热噪声在内的测量噪声水平仅比散粒噪声极限高约1.4 dB。为了演示SRS成像，我们使用了4 ps的SH脉冲和3 ps的镱光纤激光器（Yb-FL）脉冲，它们以227 fs的抖动进行亚谐波同步。通过对培养的HeLa细胞进行SRS成像，证实了CBD技术的有效性。
