Soleil-Babinet compensator

Selection of each laser depends on whether or not the experiment involves time-resolved measurement and what wavelength is suitable to exciting the target molecules. Note, that for single-molecule experiments a laser beam was circularly polarized using a Babinet-Soleil compensator to irradiate uniformly target molecules. All of the experiments otherwise unspecified were carried out at room temperature (23°C) in a clean-air booth (class 1000). 

As evident from Fig. 7, and the previous instrumental description, the LR-FDCD system appears similar in configuration to a conventional phase-modulated spectrofluorometer with the exception of the Babinet-Soleil compensator (BSC). The BSC... 

FIG. 1. The experimental arrangement BS, beam splitter VA, variable attenuator BSC, Babinet-Soleil compensator LC, liquid crystal AOM, acousto-optic modulator PR, polarization rotator P, Gian prism polarizer. 

FIGURE 6.30 Arrangement of the optical elements of a Babinet-Soleil compensator. H. W. McKenzie and R. J. Hand, Basic Optical Stress Measurement in Glass, Society of Glass Technology, Sheffield,... 

A synchronously pumped DCM dye laser was used as the picosecond light source in the pump-probe experiments. A Soleil-Babinet compensator in the excitation beam was set so that the polarization of the excitation and probe beams were parallel or perpendicular. Fluorescence anisotropies were measured with a Spex fluorolog spectrometer. The time resolved fluorescence was measured by single photon counting. 

Consequently the overall retardation is zero (Soleil-Babinet compensator) resulting in a black and white operating LCD configuration. 

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