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: A liquid cell for IRS comprising a rod-shaped crystal having a cylindrical sampling surface and integral conical end portions forming end entrance and exit faces for a radiation beam. The center of the end faces are masked. All radiation entering the entrance face internally reflects from the conical surface and propagates down the IRE by multiple internal reflections from the cylindrical sampling surface. The IRE can be sealed into a trough or flow-through housing for the liquid sample. The seals are at insensitive regions of the IRE.

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.

Abstract: An ultra-small sample analyzer for internal reflection spectrometry comprises a small hemispherical crystal of an infrared-transparent hard material whose flat surface receives the sample to be analyzed. The analyzing beam is contracted to a very small size when incident on the hemispherical surface. Pressure-applying means of a size substantially matching that of the beam at the sampling surface enables interaction of substantially the entire beam with the sample producing spectra of high contrast from microgram or nanogram quantities of the sample.

Abstract: Optical spectroscopy in a purging atmosphere wherein an optical accessory is gas-tight coupled in the spectrometer sample compartment to the open beam port of the spectrometer, whereby the same purging gas used by the spectrometer can be employed to purge the accessory. Where the accessory allows external sample placement or external adjustments, rapid sample changing or adjustment is possible without breaking the purge seal. In another embodiment, the accessory has its own purge inlet and sealed windows for receiving the spectrometer beam.

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: A novel internal reflection element provided with insensitive edges enabling mounting of the internal reflection element with adhesive or seals without spurious spectra arising from underside interaction with the mounting means.

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.

Abstract: A novel internal reflection element and associated optics for examining micro- or nano-gram quantities of a sample material by internal reflection spectroscopy, wherein the element is sized for ease of handling, and is configured to allow entrance of a radiation beam at one end, to guide the radiation to the opposite end, to concentrate the guided radiation at a small triangular-shaped sampling surface, from which the beam is directed out of the element. Adjustable masking means is also provided to reduce the unmodulated content or undesired portions of the exiting beam.

Abstract: An accessory for use with spectrophotometers for conducting IR emission spectra analyses of samples comprising a heated highly-reflecting surface for receiving the sample, an apertured reflecting mask located over the sample, and a curved reflector for collecting emissions from the sample via the aperture over a large solid angle to increase the signal-to-noise ratio.

Abstract: An internal reflection cell for use in internal reflection spectroscopy comprising a transparent body having at a bottom surface two reflecting mirrors and at a top surface means for mounting of an internal reflection prism element. A sealed cell construction is also described. The cell is intended primarily for analysis of liquid samples.