An existing fiber-optic/infrared (F-O/IR) temperature measurement system was adapted to measure the surface temperature of a thin-film aluminized polymer. The polymer under study, Kapton by Dupont, is used commonly in the aerospace industry for applications such as solar sails and solar shields. A cold plate was developed and implemented to control environmental effects on infrared data. Spectral characterization of the optical properties of Kapton was conducted to improve measurement accuracy. The instrument provides a non-contact means for accurate temperature measurement of very thin polymer membranes without distorting surface contour.
Dynamic absorption spectroscopy takes advantage of the spectral width of ultrafast femtosecond
pulses to measure complete time-resolved absorption spectra with a single pulse. To quantitatively
analyze these experiments, we have developed a time-dependent theory for dynamic absorption
spectroscopy which generalizes the usual wavepacket picture of optical absorption to the unique case
of nonstationary initial states. In our treatment, the spectrum of an initial nonstationary state is seen
to arise from the time-dependent overlap of wavepackets propagating on both the final and initial
potential surfaces of the transition. Calculations modelling the 6 fs experiments on Nile Blue and
bacteriorhodopsin are presented.