Abstract: A versatile optical analysis system comprising a spectrophotometer having a collimated radiation source, an output port for the radiation, an input port for external radiation, a detector, and means for processing electrical signals representative of radiation from a sample to be analyzed. The system also comprises one or more remote terminals where the sample is located, and novel radiation piping means for selectively piping radiation from the spectrophotometer to the remote terminal or vice versa. Novel remote terminals are also described for carrying out diffuse reflection, external reflection, or emission analysis.

Abstract: A vaariable angle reflection accessory for use in reflection spectrometry characterized by a pair of fixed ellipsoidal reflectors positioned over the sample surface and a pair of rotatable plane mirrors positions 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.

Abstract: Novel internal reflection plates and spectroscopy systems using such plates especially for analyzing liquids. The plates have a generally trapezoidal shape with beveled ends, and are oriented relative to an incident radiation beam such that the beam reflects from the bevel and propagates down the plate by multiple internal reflections form its major surfaces.

Abstract: An attachment or accessory for performing diffuse reflectance spectroscopy on a conventional UV-VIS-IR spectrophotometer. The attachment includes a removable body having a hemispherical mirrored interior surface positioned over the sample, and containing windows for entrance and exit of radiation. Multiple sampling of the same sample area enhances the quality of the spectrophotometer output.