The United States of America As Represented by the United States

Metallgesellschaft Aktiengesellschaft

University of California

Thomas R Loree

Robert E Hermes

Karlheinz Strobl

Irving J Bigio

David A Cremers

Hans-Peter Sattler

Manfred Potzschke

Leon J Radziemski

Dean L Barker

Kristian Hohla

Apparatus and method for spectroscopic analysis of scattering media. Subtle differences in materials have been found to be detectable from plots of intensity as a function of wavelength of collected emitted and scattered light versus wavelength of excitation light.

Apparatus and method for spectroscopic analysis of scattering media

A process and apparatus for the qualitative analysis of particles of various kinds of plastic which comprises passing said particles serially in a predetermined path, irradiating each particle with light of short wavelength from 180 to 500 nm, whereby each particle emits light radiation of a longer wavelength, and detecting such longer wavelength emissions for radiation intensities within a narrow wavelength range to form an emission spectrum, the emission spectrum generating a sorting signal.

Process for the qualitative analysis of plastic particles

Disclosed is a process and apparatus to analyze metal particles to determine their composition and to generate a sorting signal. The particles are exposed to a pulsed laser beam by which they are partly vaporized to form a plasma so that the particles are cleaned and the cleaned area is subsequently partially vaporized by a pulsed laser beam to form a plasma. The spectral lines of the plasma are inspected for an identification of the composition of the metal particles. The required inspection rate of 30 particles per second can readily be achieved or even exceeded if a defined narrow wavelength range or a defined wavelength is filtered from the total radiation that is emitted by the plasma and the intensities of the filtered partial radiations are related to each other to obtain ratios, which are compared with adjustable limiting values. A sorting signal is derived from the result of said comparison. The inspection rate can be improved in that the partial radiation is subjected to a comparison only for a defined interval of time.

Scrap detector

A method and apparatus for the qualitative and quantitative spectroscopic investigation of elements present in a liquid sample using the laser spark. A series of temporally closely spaced spark pairs is induced in the liquid sample utilizing pulsed electromagnetic radiation from a pair of lasers. The light pulses are not significantly absorbed by the sample so that the sparks occur inside of the liquid. The emitted light from the breakdown events is spectrally and temporally resolved, and the time period between the two laser pulses in each spark pair is adjusted to maximize the signal-to-noise ratio of the emitted signals. In comparison with the single pulse technique, a substantial reduction in the limits of detectability for many elements has been demonstrated. Narrowing of spectral features results in improved discrimination against interfering species.

Apparatus and method for the spectrochemical analysis of liquids using

A device and method for nonresonantly Raman shifting broad band uv excimer laser radiation, which enhances preselected Stokes signals by varying the pressure of the Raman scattering medium, the focal interaction length of the incident radiation within the Raman scattering medium and its power density level. Gaseous molecular H.sub.2, D.sub.2, CH.sub.4 (methane), HD and mixes thereof, and liquid N.sub.2 are used as the Raman scattering medium to frequency shift the outputs of high power KrF and ArF lasers. A cable fed discharge with an unstable resonant cavity configuration is utilized to produce the output laser power levels required for operation.

Growing community of inventors

Los Alamos, NM, United States of America

Thomas R Loree