Abstract: An optical accessory for reflection spectroscopy having a very small sampling area and provided with a microscope for aiding the user to locate a sample to be analyzed on the active sampling area where it can interact with a radiation beam. The microscope is characterized by fiber optic bundles to supply sample illumination via a cone-shaped light-funnelling tip terminated in a thin hard optically transparent wear tip, e.g., of sapphire. The microscope is also used to apply pressure via the wear tip to the sample while it is being illuminated and while it can be viewed to maximize interaction with the radiation.

Abstract: A variable angle reflection accessory for use in reflection spectrometry characterized by a pair of fixed ellipsoidal reflectors positioned inside an enclosure adjacent a sample surface on the outside of the enclosure and a pair of rotatable plane mirrors positioned at opposite sides of the sample surface. The spectrometer beam is brought to a focus at the first plane mirror, from which it is reflected off the first ellipsoidal reflector to a focus at the sample surface. The reflected beam follows a corresponding path back to the spectrometer. Rotating the mirrors in unison causes the beam angle of incidence on the sample surface to vary over a wide range while maintaining optical alignments and continuing to center the radiation on the same sample area. The outside positioning of the sample surface allows the accessory to be easily coupled to a purge port of the spectrometer and allows rapid sample exchanges without breaking the purge atmosphere.

Abstract: The multiple internal reflection accessories for internal reflection spectrometry described here utilizes a novel approach to match the round beam size and shape from a conventional FT-IR spectrometer to the typical rectangular IRE aperture. Its transfer optics distort the beam entering and exiting the IRE so that the cross-section of the beam is matched to that of the standard rectangular aperture of the IRE. This configuration reduces energy losses, eliminates the need to aluminize the edges of the crystal, and reduces spurious peaks from the adhesive or O-rings used to conventionally mount the crystal.