Dual-wavelength-excitation aerosol fluorescence spectra detection using combined spectrometer with Czerny-Turner...

We developed a dual-wavelength-excitation aerosol fluorescence spectra detection device prototype. In our system, the 263 nm and 355 nm lasers are used to sequentially excite the fluorescence of aerosol stream, which is located spatially and temporally by two crossed infrared lasers; a bifurcated fiber bundle is applied to receive the fluorescence spectra of 274-463 nm and 374-565 nm. Besides, with a 32-channel photomultiplier tube as detector, a self-developed combined spectrometer with Czerny-Turner design is employed to detect the two band spectra in a preset timing sequence. Experiments show that the system can detect the fluorescence spectra, after dual-wavelength-excitation, of three intrinsic fluorophore samples and three bioaerosol samples.