Abstract
To measure the optical spectra of microcrystals up to -20μm in diameter, microcomputer processed, polarizing microscope-spectrophototometer method has been introduced. The 2nd optical source, Hg-lamp (Epi-illuminater), is mounted in the polarizing microscope to measure the fluorescence spectrum. Transmittance of reference (I0) and that of a sample (I) are measured independently in the same single beam condition, and each optical data are stored in the floppy disk of microcomputer. Absorbance, log(I0/I), can be calculated using the data stored in the disk. The power of detection and resolution of the spectrophotometer is tested by using ruby and Hg spectra. The weak spin-forbidden transitions, R and B-lines of Cr+3 in ruby are clearly detected. Precision of the spectral position and resolution (full width at half maximum Γ), are obtained : ruby fluorescence R1 694.32±0.07nm, Γ0.69, R2 692.89±0.06nm, Γ0.62: Hg Γ0.05 nm at 546.074 nm. Some examples of visible absorption spectra are given.
