Fluorescence-based temperature measurement in laser-induced vapor bubbles
Fluorescence-based temperature measurement in laser-induced vapor bubbles
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激光诱导蒸汽泡中基于荧光的温度测量
DOI：
10.1117/12.308174
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发表时间：
1998
期刊：
影响因子：
--
通讯作者：
A. Welch
中科院分区：
文献类型：
--
作者：
Kin F Chan;T. Pfefer;D. Hammer;E. Jansen;M. Frenz;A. Welch
设计了一种基于荧光的温度探头（光极），用于测量激光诱导的蒸汽泡内的温度。光极由400微米的光纤组成，光纤尖端附着有掺杂罗丹明B的聚氨酯薄膜。该膜表现出4ns的荧光衰减时间，并且所测量的荧光产率在20至110摄氏度的范围内是温度依赖性的。使用Ho：YAG激光器（（λ）等于2.12微米，（τ）p等于250微秒），通过光纤传送的脉冲能量为256 ± 7 mJ，以产生蒸汽泡。气泡在激光脉冲开始后200微秒达到最大膨胀，平均寿命为350微秒。通过将光极定位在蒸汽泡内并用氮染料激光器（（λ）等于540 nm，（τ）p等于500 ps）激发其荧光膜涂覆的尖端来测量温度。在最大膨胀时，蒸汽泡中的温度约为61摄氏度，表明低于大气压的饱和蒸汽压。最大膨胀时的蒸气压由瑞利方程确定。
A fluorescence-based temperature probe (optrode) was designed to measure temperature within laser-induced vapor bubbles. The optrode consisted of a 400-micrometer optical fiber with a rhodamine B-doped polyurethane film attached to the fiber tip. The film exhibited a fluorescence decay time of 4 ns, and the measured fluorescence yield was temperature dependent in the range from 20 to 110 degrees Celsius. A Ho:YAG laser ((lambda) equals 2.12 micrometer, (tau) p equals 250 microseconds) with a pulse energy of 256 plus or minus 7 mJ delivered through a fiber was used to produce the vapor bubbles. The bubbles reached maximum expansion 200 microseconds after the onset of the laser pulse and had an average lifetime of 350 microseconds. The temperature was measured by positioning the optrode within the vapor bubble and exciting its fluorescent film-coated tip with a nitrogen dye laser ((lambda) equals 540 nm, (tau) p equals 500 ps). At maximum expansion, the temperatures in the vapor bubbles were approximately 61 degrees Celsius, indicating sub-atmospheric saturated vapor pressures. The vapor pressure at maximum expansion was confirmed by Rayleigh's equation.