US 4,864,142 A · Method and apparatus for the noninvasive interrogation of objects

Abstract

Neutron elastic scatter resonance is employed for the noninvasive interrogation of objects as for example to detect explosives and narcotics in closed containers. A resonant scattering spectrum of the object is obtained by projecting a collimated, monoenergetic beam of neutrons onto the object, varying the energy of the beam and measuring the scattered neutrons as a function of the beam energy. The thus generated spectra and analyzed so as to determine either the pressence of particular elements of interest or the relative ratios of those elements. Ratios so determined may be compared with corresponding ratios established for contraband items. If the ratios fall within the range for contraband, an alarm indication is provided. The present invention provides method and apparatus for contraband detection.

Claims49

Dependent claims

Apparatus for the noninvasive inspection of an object so as to determine the presence of at least one preselected element therein, said apparatus comprising:

a neutron beam source for generating a beam of neutrons having a preselected energy and directing the beam onto the object;
a neutron beam energy controller for varying the energy of the neutron beam over a preselected range, in which resonant scattering of the beam by said at least one preselected element will occur;
neutron detector means disposed so as to receive neutrons scattered from the object and generate a signal corresponding thereto;
and
analyzer means for (1) analyzing the signal from said detector so as to determine if resonant scattering of the neutron beam by the object has occurred at an energy corresponding to resonant scattering by said at least one preselected element, and (2) providing an alarm indication if the resonant scattering of the neutron beam so corresponds, such that the presence of said at least one preselected element is indicated.

2 more elements

A method for the nonvisual inspection of an object to determine the presence of at least one preselected element therein including the steps of:

directing a beam of neutrons onto the object;
varying the energy of said neutron beam over a preselected energy range in which resonant scattering of the beam by said at least one element will occur;
detecting the scattered neutrons and generating a signal corresponding thereto;
analyzing the signal to determine if resonant scattering of the neutron beam by the object has occurred at an energy corresponding to resonant scattering by said at least one preselected element;
and
providing an alarm indication if the resonant scattering so corresponds.

3 more elements

Dependencies are inferred from the claim text.

Method and apparatus for the noninvasive interrogation of objects

Life of this patent

Method and apparatus for the noninvasive interrogation of objects

Life of this patent

Abstract

Claims49