Tuneable-laser based time-resolved fluorescence spectrophotometer FLS980

Fluorescence measurements involve exciting a sample (powder or liquid) with light of one wavelength and then measuring difference light (luminescence) which is emitted. The equipment consists of a xenon lamp with double monochromator to provide continuous excitation) and a laser with optical parametric oscillator (OPO) to provide pulsed excitation, both of which can be tuned to different wavelengths starting at about 200 nm in the far ultraviolet region. The system also has a powerful fixed wavelength infrared laser for upconversion studies and several very fast pulsed fixed wavelength EPLED light sources in the UV for lifetime measurements. Luminescence is detected using two possible PMTs (photomultiplier tubes), one sensitive in the visible part of the spectrum and another in the infrared region, or with a CCD (charge coupled device) camera which is less sensitive but faster. Both excitation and emission spectra will be corrected for the spectral response of the system e.g. the efficiency of light sources, mirrors, diffraction gratings, optical filters and detectors. An integrating sphere is provided to capture light emitted from the samples in different directions for quantum yield measurements and a cryostat is provided so that samples can be cooled from room temperature to about 10 K on the absolute temperature scale. By monitoring the emission of samples after pulsed excitation using the PMTs and fast photon-counting electronics, the system can be used to measure the lifetime of phosphorescent materials. The system includes variable slits and filters and is controlled through a single software package, while an advanced software package for the analysis of time-resolved data is also included.