J Biomed Opt. 1996 Jan;1(1):124-30. doi: 10.1117/12.227105.
A directly modulated infrared diode laser was frequency doubled in an intracavity KTP quasi-phase-matched waveguide, producing modulated laser light at 425 nm, which was subsequently employed for phase fluorometric detection of CO and O gases. The frequency-doubled source was coupled to a single optical fiber to deliver the excitation light to the sensor mounted at the fiber tip. Fluorescence from the sensor returned through the same fiber to a photodetector. This compact, low-power source provided continuously tunable modulation frequencies up to 200 MHz. In the detection of CO, the doubled infrared diode laser produced 425-nm light that was modulated to a depth of 27% at a modulation frequency of 95 MHz.
一个直接调制的红外二极管激光器在腔内 KTP 准相位匹配波导中进行倍频，产生了 425nm 的调制激光，随后用于 CO 和 O 气体的相荧光检测。倍频源与单根光纤耦合，将激发光输送到安装在光纤尖端的传感器。传感器的荧光通过同一光纤返回至光电探测器。这种紧凑、低功率的光源提供了连续可调谐的调制频率，最高可达 200MHz。在 CO 的检测中，倍频后的红外二极管激光器产生了 425nm 的光，在 95MHz 的调制频率下调制深度为 27%。
