Assembly and Performance of a Double-Beam Microscope Spectrophotometer from Commercial Instruments

Abstract

A microscope spectrophotometer assembled from commercially available instruments has been used to obtain visible and near‐infrared spectra on selected specimen areas as small as 1 μ². A commercial spectrophotometer is coupled to a research microscope equipped with a photometer tube to which the photodetector of the spectrophotometer is attached. The miscroscope spectrophotometer can be assembled easily, quickly, and in a very compact form with a minimum of machine work. The performance characteristics are discussed, as well as some applications. The instrument was designed for spectral investigations of substances under pressure, but is equally well suited to the study of conventional microscope specimens. The incorporation of cameras and polarizing optics makes the instrument particularly suited to phase studies as well. Applications discussed are the shift of absorption bands with pressure, the determination of the pressure gradient in the diamond high pressure cell, and the determination of the spectra of microsections of stained biological specimens.