A miniaturised laser-induced fluorescence system with a fiber-optic probe for the analysis of aromatic compunds

摘要

We introduce a fiber optical sensor which is capable of analysing polycyclic aromatic hydrocarbons (PAHs) and monoaromatics like benzene, tolouene, xylene, and ethylbenzene (BTXE). The compact system is based on laser-induced. time-resolved fluorescence emission spectroscopy. It uses a miniaturised all solid state laser which can be operated alternately at 266 nm and 355 nm. The excitation light is guided through an optial fiber to the sensor head. The fluorescence light is collected by 4 optical fibers, which are placed around the excitation fiber, and guided to a detector, which consists of a spectrograph, a gateable image intensifier and a CCD camera. Time resolved spectra are recorded by moving the gate relative to the laser pulse.