Abstract: A high sensitivity radiation imaging system, aimed to perform sections (or tomographic) images of emitted radiation. This system includes a collimator having at least two openings in which the narrowest cross-section is greater than twice the intrinsic resolution of the detector so that different points of radiation impact can be detected in each opening. The plurality of openings differs in shapes, dimensions or orientations in order to provide a better overlap of their impulse function in the Fourier space. The camera head is displaced by successive steps, the successive steps being of the order of magnitude of a predetermined image resolution. Information collected by the detector is processed by storing locating information corresponding of the impact points for each position of the openings during displacement, and processing the information to reconstruct the radiation volume density function.

Abstract: A detection apparatus for detecting an electron cloud includes a resistive anode layer with a detection plane upon which the electron cloud is incident. The resistive layer is capacitively coupled to a readout structure having a conductive grid parallel to the detection plane. Charge on the resistive layer induces a charge on the readout structure, and currents in the grid. The location of the induced charge on the readout structure corresponds to the location on the detection plane at which the electron cloud is incident. Typically, the detection apparatus is part of a detector, such as a gas avalanche detector, in which the electron cloud is formed by conversion of a high-energy photon or particle to electrons that undergo avalanche multiplication. The spacing between the anode layer and the readout structure is selected so that the width of the charge distribution matches the pitch between conductive segments of the grid.

Abstract: The apparatus and method provide a technique for more simply measuring alpha and/or beta emissions arising from items or locations. The technique uses indirect monitoring of the emissions by detecting ions generated by the emissions, the ions being attracted electrostatically to electrodes for discharge of collection. The apparatus and method employ a chamber which is sealed around the item or location during monitoring with no air being drawn into or expelled from the chamber during the monitoring process. A simplified structure and operations arises as a result, but without impairing the efficiency and accuracy of the detection technique.

Abstract: A pipe switching unit switches connections between the radiation monitor side and a plurality of sampling pipes which are installed in different sampling places to introduce air from the respective sampling places. An intermittent dust radiation monitor collect, in a dust collection section, dust in the air introduced through each sampling pipe sequentially switched by the pipe switching unit, and measures the radioactivity concentration of dust in the dust collection section. A continuous dust radiation monitor collects, in a dust collection section, dust in the air introduced through a fixed sampling pipe switched by the pipe switching unit, and measures the radioactivity concentration of dust in the dust collection section. With this arrangement, while intermittent measurement is performed in normal operation as in the prior art, the intermittent measurement is switched to continuous measurement, as needed, thereby improving the measurement precision.

Abstract: The invention provides a compact and high performance infrared radiation detector. The infrared radiation detector contains: a substrate; and at least two infrared radiation detector units selected from the group consisting of a pyroelectric infrared radiation detector unit, a resistive bolometer type infrared radiation detector unit and a ferroelectric bolometer type infrared radiation detector unit, the infrared radiation detector units being disposed on the same side of the substrate.

Abstract: The present invention discloses a radiation image detector including an ionizing radiation sensing element which is operative to present an imagewise electrostatic charge distribution in response to imagewise ionizing radiation exposure thereof; a charge generator, in non-contact proximity with the radiation sensing element, which is operative to inject charge onto said radiation sensing element; an optical radiation source which projects visible radiation onto the radiation sensing element; and read circuitry, which detects information-bearing signals, representing said imagewise electrostatic charge distribution, the signals being created when the charge generator and the optical radiation source are concurrently activated in generally mutual registration.

Abstract: A Compton camera has two detectors which each sense the location, energy and time of photon collisions. Compton events are detected in which a photon emanating from the subject collides with one detector at energy (E1) and then the second detector at (E2), both energies E1 and E2 are measured and used in conjunction with an initial photon energy E0 to increase the resolution of the camera.

Abstract: A method for measuring the fluorescent lifetime of an unknown fluorescent sample, such as a biological liquid, without the requirement of manual intervention or a separate reference standard. An energetic light beam having its low energy component filtered out is shined on the sample. An optical detector is positioned such that the intensity of the components of the light beam reflected from the sample reaching the detector is substantially minimized but light remitted and/or fluoresced by the sample does reach the detector with non-trivial intensity. Errors arising from the electronic components of the system, such as RFI and D.C. offset errors, are isolated and minimized by positioning an opaque filter between the sample and the detector and measuring the resulting signal. The resulting baseline measurement data is stored for later error subtraction.

Abstract: A shield for a detector or prism of a particle detection system has a body mountable on the detector or prism, divided into first and second compartments by an intermediate wall with a hole therethrough. Air diffuser units In the first compartment (adjacent the detector or prism) generate a stable column of air which prevents the particles contacting the beam window of the detector or prism.

Abstract: A device for the detection of multi-spectral infrared and visible radiation using a bolometric detector having at least one active layer and two control electrodes for the detection of both infrared and visible radiation, and also using at least one photodetector having at least two active layers and two control electrodes for detecting solely visible radiation. The device is uncooled, and the two detectors are superimposed and combined with one-another for forming the same sensitive element.

Abstract: A detector 1 for use in infrared gas analyzers has two compartments 14 and 15 to be filled with gas G showing the same absorption characteristics as the gas to be measured and which are arranged in series with a load cell 2, and the gas compartments 14 and 15 communicate with each other via a gas channel 16 in which a pyroelectric flow detector element 19 is provided.

Abstract: An electromagnetic radiation emitter which utilizes a precompensator, pulsed light signal, optical fiber cable, and a terahertz radiation generator. The present invention incorporates an optical precompensator to correct for the stretching of an optical signal as it travels through an optical fiber cable. The dispersion characteristics of the precompensator will be equal and opposite to the dispersion characteristics of the optical fiber cable, maintaining the fidelity of optical pulses as they travel through and exit the optical fiber cable striking a device that generates terahertz electromagnetic radiation.

Abstract: This detector has a resistive element (4) able to undergo heating which is provided with electrical biasing means (6, 8) for amplifying or increasing the heating, a thermometer (12) thermally coupled to the element and converting a temperature variation undergone by the thermometer into an electric signal, and a device (18) for reading the electric signal. The invented detector can be applied to measure and detect infrared radiation. The detector can also be applied to measure and detect radiation of different wavelengths.

Abstract: A multi-detector system receives incident radiation through a subject includes a gaseous microstrip detector, which has alternating anodes and cathodes on a substrate opposite a voltage source, is positioned adjacent a semiconductor detector. In a dual energy environment, electric fields are applied to both detectors as the incident radiation is directed therethrough. A gas electron multiplier is placed within the gas microstrip detector, and a potential is applied thereto to improve the generated signal. To further improve this signal, the anode and cathode may be operated as a Frisch Grid. Accordingly, the detectors generate corresponding signals which are compared to generate a contrasted signal of the subject. These signals may be generated for imaging, radiation monitoring, radiation measuring and the like. The direction of incident radiation and the orientation of the electric fields may be adjusted according to the particular application.

Abstract: An ultraviolet (UV) catadioptric imaging system, with broad spectrum correction of primary and residual, longitudinal and lateral, chromatic aberrations for wavelengths extending into the deep UV (as short as about 0.16 &mgr;m), comprises a focusing lens group with multiple lens elements that provide high levels of correction of both image aberrations and chromatic variation of aberrations over a selected wavelength band, a field lens group formed from lens elements with at least two different refractive materials, such as silica and a fluoride glass, and a catadioptric group including a concave reflective surface providing most of the focusing power of the system and a thick lens providing primary color correction in combination with the focusing lens group. The field lens group is located near the intermediate image provided by the focusing lens group and functions to correct the residual chromatic aberrations. The system is characterized by a high numerical aperture (typ. greater than 0.

Abstract: The present invention discloses an ionizing radiation sensitive multi-layer structure having a charge accepting outer surface and comprising a conductive layer, said ionizing radiation sensitive multi-layer structure being operative such that imagewise ionizing radiation impinging on said ionizing radiation sensitive multi-layer structure causes a charge distribution, representing said imagewise ionizing radiation, to be formed in said conductive layer; and readout electronics coupled to said conductive layer to detect the charge distribution formed in said conductive layer.

Abstract: The present disclosure presents an apparatus for radiation detection comprising a generally uniform dielectric layer, a conductive layer interfacing a first surface of the generally uniform dielectric layer; an ionizing radiation detection multi-layer structure including a photoelectric conversion layer interfacing a second surface of the generally uniform dielectric layer; said ionizing radiation detection multi-layer structure, said generally uniform dielectric layer, and said conductive layer being configured with respect to each other and being operative such that an imagewise ionizing radiation pattern impinging on said ionizing radiation detection multi-layer substrate causes a corresponding charge pattern representing said imagewise ionizing radiation to be generated at the interface between the generally uniform dielectric layer and the photoelectric conversion layer and causes a readable imagewise replica of said charge pattern to be formed in said conductive layer.

Abstract: An emergency egress system for a locus that is exposed to light in non-emergency use and susceptible to interruption or termination of light in emergency circumstances. The emergency egress system comprises a fibrous web deployed in the locus, wherein the fibrous web has photoluminescent fiber incorporated therein in sufficient amount and distribution to illuminate the web or predetermined portions thereof during the interruption or termination of light in emergency circumstances, and subsequent to light exposure thereof.

Abstract: A composite phosphor screen for converting radiation, such as X-rays, into visible light. The screen includes a planar surface, which can be formed from glass, silicon or metal, which has etched therein a multiplicity of closely spaced microchannels having diameters of the order of 10 microns or less. Deposited within each of the microchannels is a multiplicity of phosphors which emit light when acted upon by radiation. The walls of the microchannels and/or the substrate surfaces include light reflective coatings so as to reflect the light emitted by the phosphors to the light collecting devices, such as film or an electronic detector. The coatings can be either radiation transparent or filtering/attenuating depending on the particular application.

Abstract: An in-line spectrometric method for determining the distillation residue content in an opaque, dark-colored mixture containing an isocyanate and tar-like materials (residue) during the isocyanate production process. A probe capable of directing light at wavelengths of from 1050 to 2150 nm is inserted in a stream of the residue-containing mixture and light is transmitted through the stream. Light absorption data is collected and a near-infrared spectrum is generated. The residue content is then determined using a chemometric model. Knowledge of the residue content makes it possible to control and optimize the distillation process.