Abstract:
A method of measuring in real time a dose of radiological radiation absorbed by a region under inspection subjected to a flux of radiological radiation, the method comprising the steps consisting in: a) detecting the incident radiation at at least one point of the region under inspection using at least a first bundle of measurement optical fibers (2) containing at least one fiber placed in said region under inspection and adapted to generate a light signal on receiving radiological radiation; b) measuring said light signal away from the region under inspection after it has been transmitted along the measurement optical fiber; and c) determining the dose of radiological radiation received by said measurement optical fiber on the basis of said light signal.
Abstract:
A two-dimensional ionising particle detector including a matrix of detecting fibers, each detecting fiber forming a pixel of the detector. Each detecting fiber is composed of a glass capillary filled with a liquid scintillator for which the chemical composition is chosen such that an average free path of primary scintillation photons is negligible compared with a diameter of the capillary. The detector is applicable, for example, to high resolution particle imagery.
Abstract:
A radiation detection device, system, and method for use in homeland security is disclosed. The device is portable and includes a photomultiplier tube (PMT) connected to an end of a substantially rigid thin-walled aluminum tube. Inside the aluminum tube, a substantially straight scintillating fiber is disposed (so as to be shielded from ambient light), and an end of the scintillating fiber is optically coupled to the PMT. A voltage output signal from the PMT is signal-processed with a filter to remove high-frequency noise (which may arise from solar radiation spikes) and fed to a voltage-responsive alarm or signalling device. The portable device is employed, for example, by responders to nuclear incidents and is packaged as a small wearable hands-free and eyes-free unit with a continuous in-use self-testing feature.
Abstract:
A radiation detection device, system, and method for use in homeland security is disclosed. The device is portable and includes a photomultiplier tube (PMT) connected to an end of a substantially rigid thin-walled aluminum tube. Inside the aluminum tube, a substantially straight scintillating fiber is disposed (so as to be shielded from ambient light), and an end of the scintillating fiber is optically coupled to the PMT. A voltage output signal from the PMT is signal-processed with a filter to remove high-frequency noise (which may arise from solar radiation spikes) and fed to a voltage-responsive alarm or signalling device. The portable device is employed, for example, in baggage and vehicle radiation scanning systems, as well as for large-area radiation mapping and directional radiation sensing.
Abstract:
The present invention is a directed to a non-pixilated scintillator array for a CT detector as well as an apparatus and method of manufacturing same. The scintillator array is comprised of a number of ceramic fibers or single crystal fibers that are aligned in parallel with respect to one another. As a result, the pack has very high dose efficiency. Furthermore, each fiber is designed to direct light out to a photodiode with very low scattering loss. The fiber size (cross-sectional diameter) may be controlled such that smaller fibers may be fabricated for higher resolution applications. Moreover, because the fiber size can be controlled to be consistent throughout the scintillator array and the fibers are aligned in parallel with one another, the scintillator array, as a whole, also is uniform. Therefore, precise alignment with the photodiode array or the collimator assembly is not necessary.
Abstract:
A fiber optic scintillator includes, for example, a first plurality of radiation absorbing elements comprising a scintillating material for converting radiation into light and a second plurality of radiation absorbing elements interspersed among the first plurality of radiation absorbing elements. The first plurality of radiation absorbing elements has a first radiation absorption efficiency. The second plurality of radiation absorbing elements has a second radiation absorption efficiency and an effective atomic number greater than about 50. The second radiation absorption efficiency is greater than said first radiation absorption efficiency. A scintillator forming method provides a bundle of the second plurality of radiation absorbing elements interspersed among the first plurality of radiation absorbing elements by drawing the bundle, The drawn bundle is cut into a plurality of sections. The plurality of sections are assembled to form the scintillator having an array of parallel first and second radiation absorbing elements.
Abstract:
A detector (20) for high voltage x-rays includes a plurality of sensor elements (22) with each sensor element being aligned along a respective focal axis (25) with respect to a high voltage x-ray source (24). A fiber optic scintillator (34) is optically coupled to each of said sensor elements and is disposed to receive incident x-ray radiation passing from the object to be imaged. Optical fibers of the scintillator are positioned such that their optical axes are perpendicular to incident x-rays. Each sensor element has a length along the focal axis sufficiently long for the fibers to absorb substantially all incident x-rays. Each sensor element comprises an array of amorphous silicon photosensors disposed to detect light generated by the scintillator.
Abstract:
In a depth dose measuring device, a light is outputted from an end surface of a block-type detector (202) formed by tying a plurality of scintillation fibers in a bundle, a spectroscope (204) is used to disperse the light so as to measure an amount of light having a wavelength corresponding to an emission spectrum of the scintillation fibers, a picture measuring device (205) and a picture processing device (206) calculate an emission distribution of only a scintillation light depending upon an emission distribution in which the scintillation light and a Cerenkov light are mixed, and a result is displayed on a display device (207).
Abstract:
A hybrid luminescent device for converting ionizing and penetrating radiation energy such as x-rays, gamma rays, neutrons, ions, electrons, and the like into visible light for imaging applications. The hybrid luminescent device includes a phosphor screen disposed on an entrance face fiber optics scintillator which, in turn, may be removably coupled to a camera or like recording media. The hybrid luminescent device of the present invention is capable of providing enhanced radiation absorption efficiency, higher spatial resolution and enhanced brightness or luminescence output over that which is achievable by the phosphor screen and/or fiber optics scintillator when used separately as an intensifying screen for imaging of ionizing and/or penetrating radiation.
Abstract:
It is an objective of the present invention to provide a scintillation counter that can measure the intensity of only .beta. rays. Two scintillation fibers (11 and 12) which emit different wavelengths are provided in series to a probe (10). One of the scintillation fibers (12) is covered with a .beta.-ray shield. The optical signal generated at the probe (10) is transmitted through the optical fiber (20) and separated by the light separating element (31). One portion of the separated optical signal is incident on a light detector (32) and the intensity of the incident light detected. The other portion of the separated optical signal is incident on a light detector (33) and the intensity of the incident light detected.