Spectrometer for Optical Studies of Ultra-Thin Films

Abstract

An optical spectrometer for study of the optical absorption of monomolecular films spread on water is described. The spectrometer is a multiple‐pass instrument, suitable for measurements from approximately 3800 to 8000 Å. It employs a chopper‐stabilized monochromatic light source, with a collecting lens and integrating sphere combination to circumvent light shimmering noise. Detection is by means of a photomultiplier tube. Representative results for monomolecular films of chlorophyll a are presented.