Abstract: A method and an arrangement for determining properties of fibers in a supension of said fibers with the aid of spectroscopic measurements carried out in a wavelength range within the near infrared range (NIR), comprising introducing the fiber suspension into a measuring cell (20) which is provided with a filter (35) and an outlet (47) at one end thereof; concentrating the fiber suspension in the cell while simultaneously measuring the absorbency until a predetermined value is obtained at that wavelength at which the measurement is effected, or for the highest peak of the registered spectrum, at which point supply of the suspension is stopped, the outlet (47) from the cell is closed and a complete spectrum within the wavelength range is registered, whereafter the sought properties of the fibers are determined in a computer unit on the basis of earlier calibrations carried out on samples of known fiber properties.

Abstract: A radiation image storage panel comprising a stimulable phosphor layer and an erasing light-diffusion preventive layer capable of allowing transmission of stimulated emission while preventing an erasing light from diffusing within the preventive layer along its plane is favorably employed in a radiation image reading system employing a double-side reading system in which a stimulating step and an erasing step are simultaneously performed in parallel on the same storage panel.

Abstract: Thermal imaging system (10) includes a focal plane array (18) having pixels (20). Signals produced by pixels (20) are addressed by integrated circuit substrate (22) and passed to video processor (24). Video processor (24) includes, among other modules, a detection and substitution module (28) that detects defective pixels (21) and substitutes the signals produced by defective pixels (21). The detection and substitution of signals produced by defective pixels (21) may be performed while viewing the thermal scene (12) or while stimulating pixels (20) with a stimulus. A thermal stimulus may be generated by a thermoelectric cooler (50) thermally coupled to integrated circuit substrate (22) and focal plane array (18). An electrical stimulus to identify defective pixels (21) may also be delivered to pixels (20) of focal plane array (18).

Abstract: An x-ray image sensor has a matrix of radiation-sensitive detector elements, the detector elements being connected in two groups to a common read-out line on which bipolar signals are generated. Read-out signals of one polarity cause read-out of one of the groups of detector elements and read-out signals of the other polarity cause read-out of the other group. An image detector having high resolution but low technical outlay is thereby achieved.

Abstract: A passive millimeter-wave imaging system configured as an integrated circuit. The imaging system incorporates a lens which focuses radiation from a scene onto a detector in the focal plane of the lens. The detector includes an outer array of ferroelectric elements in which each element includes a top metal film and a ferroelectric layer. Millimeter-wave radiation from the beam causes charge build-up in the ferroelectric layers. The charge build-up is sensed by appropriate amplification and signal processing circuitry associated with the read-out electronics so as to provide a signal indicative of obstacles in the scene to a video system. The ferroelectric layer can also be used as an antenna for each pixel element.

Abstract: A method of determining a physical parameter of geological formations having a borehole passing therethrough by using a sonde lowered down the borehole at the end of a cable and including a source of gamma radiation, a very near detector, a near detector, and a far detector, the method being characterized in that: for each energy window, a model is created characteristic of the response of each detector; a "low resolution" value of the looked-for parameter is determined which, when applied to the model, gives rise to a theoretical measurement that is substantially equal to the "low resolution" real measurement obtained by combining the measurements from all three detectors; the measurements from the two detectors nearest the source are combined to constitute a "high resolution" real measurement; and a "high resolution" value of the parameter is determined which, when applied to the model, gives rise to a theoretical value that is substantially equal to the "high resolution" real measurement, the determination

Abstract: Two conjugate views of a patient are acquired during a SPECT nuclear medicine study. A common anatomical feature is identified in the views. Based on the differences in location of the common feature in the views, the center of rotation ("COR") of the detector during the study can be calculated after the study has been concluded. This COR can then be used during image reconstruction to determine the location at which each filtered view is backprojected. The resulting SPECT data is of higher quality because COR artifacts in the reconstructed image are reduced or eliminated.

Abstract: A radiation detector employs a thermopile having a potentiometer for calibrating the thermopile output to best suit a particular output meter and sensing application. A thermocouple may be connected in series with the thermopile. The output of the thermopile is calibrated to best match a linear function which intersects the thermopile output function at a temperature in the center of a temperature range of interest. A total output signal of the detector is the sum of the thermopile signal and the thermocouple signal, and is indicative of the temperature of a target emitting radiation sensed by the thermopile. The series connection of the thermopile and the thermocouple allow the thermopile hot junction temperature to be referenced to the cold junction temperature of the thermocouple. Thus, the reference temperature may be remote from the thermopile sensor. A filtering lens may be used to prevent short wavelength radiation from reaching the thermopile sensor, improving the linearity of the thermopile response.

Abstract: To spectrally detect a contaminant in a moving container, a set of reference spectral information related to one or more containers having known contents is stored. Thereafter, radiant energy is directed at liquid near the bottom of the container so that the radiant energy is modified by the contents of the container and travels through the contents of the container in multiple paths of varying length. Spectral information from detected portions of the modified radiant energy is obtained, and is compared to the stored set of reference spectral information using correlation techniques. Based on the relationship between this spectral information and the stored set of reference spectral information, the presence or absence of a contaminant is indicated.

Abstract: A compact, movable scan head having multiple scanning modalities and capable of high speed, high resolution scanning of a variety of samples is disclosed. Stimulation and detection of storage phosphor screens and fluorescent samples are preferably achieved with a first and second channel in the optical path of the first side of the scan head. This first side preferably has a laser diode light source. Reading of reflective and transmissive signals is also possible. A third channel is available in the optical path of the second side of the scan head. This third channel preferably provides LED point scanning and reading of fluorescence, reflective, and transmissive signals received from the sample. The various modalities of the scan head of the present invention may or may not have coincident optical paths. Any two of the above channels, or additional channels similar to the above channels, may be incorporated into the scan head.

Abstract: A thermal imaging system (10) including a housing (12) having a cavity (28) therein is provided. A plurality of thermal sensors (14) are placed in the cavity (28) of the housing and an IR window (16) in the opening of the cavity protects the thermal sensors (14). The IR window (16) includes first (18) and second (20) faceplates formed from an IR transmissive material and a honeycomb support structure (22) between the faceplates for supporting the faceplates. The window (16) may also include an adhesive layer (25 & 26) between each faceplate and the support structure (22) for adhering each faceplate to the support structure (22).

Abstract: A fiber optic sensor for detecting at least one chemical by evanescent wave spectroscopy comprises a generator of a light signal, a mirror for introducing the light signal into a fiber, a clad optical chalcogenide glass fiber, a mirror for directing the light signal from the fiber into a detector, and a detector for detecting chemicals by the fiber. The fiber comprises a core and a clad having lower refractive index than the core enveloping and being in continuous contact with the core, at least one region on the fiber completely or partially devoid of the clad, and a polymer disposed in the region having affinity for the chemical(s). There being a different polymer in each region if there is more than one region.

Abstract: An object of the present invention is to provide a radiation site detector which can detect a position of an incident scintillator with high precision by excluding the effect of Compton scattering. The radiation site detector is provided with a scintillator array having a plurality of scintillators into which a radiation is made incident, and a photodetector for converting scintillations occurring in the scintillators to independent photoelectric conversion signals to output them. A level of each of photoelectric conversion signals output from a specific scintillator to be judged whether the radiation has been incident thereinto, and from a plurality of scintillators around the specific scintillator, is compared with a plurality of threshold values different from one another so as to determine whether the levels are within or outside a window defined by the threshold values.

Abstract: A radiographic phosphor panel having metal hydride stabilizer compound. The phosphor panel has a support and a luminescent layer overlaying the support. The luminescent layer includes phosphor crystals, and binder. The oxosulfur reducing agent can be added to the luminescent layer. The oxosulfur reducing agent has a concentration sufficient to substantially increase the photostimulated luminescence of the panel.

Abstract: A thermal-type infrared detecting element is provided which includes an infrared detecting member, a support member supporting the infrared detecting member, a substrate holding the support member, and a low thermal conduction part intervening between the substrate and a central portion of the support member, the support member having a link portion in at least a peripheral portion thereof which links the support member to the substrate and slits and/or grooves defined at a location adjacent the link portion. This infrared detecting element exhibits excellent sensitivity and responsiveness while requiring no cooling, and a one- or two-dimensional array of the element assures clear imaging with less crosstalk.

Abstract: This invention relates to a fabrication of a gamma camera plate assembly that has long life and improved efficiency. Cladding and reflecting layers provide improvements in crystal output. Seals prevent moisture leaks, prolonging lifetime. Multi-barrier epoxy-filled seals and desiccant-filled recesses, elastomer-filled spaces and an extra optical coupling layer provide prolonged life and improved efficiency. Exterior rings with new glass-to-metal seals and metal-to-metal seals provide strong watertight assemblies. The gamma camera plate includes a crystal having an optical cladding and a reflector surrounding the cladding. A glass mounting plate is connected to one flat surface of the crystal by an optical coupler. A mounting ring surrounds the crystal and an outer surface of the glass plate. Barriers are formed in upper and lower surfaces of the mounting ring, and complementary barriers are formed in engaging surfaces of the glass plate and of the gamma ray window plate.

Abstract: The present invention is an apparatus for examining a body part. The apparatus comprises a mechanism for immobilizing and compressing the body part. The apparatus also comprises a mechanism for providing an internal anatomical image of the body part and a mechanism for detecting single gamma-rays emitted by a radiotracer infiltrated into the body part. The detecting mechanism is disposed in an adjacent relationship with the mechanism for providing an internal anatomic image so that the body part remains in the same position during and between anatomic and radiotracer imaging. In one embodiment, the detecting mechanism includes a detector module disposed on one side of the immobilizing mechanism. The detector module preferably has at least one array of gamma ray sensitive material in communication with a position detector. In another embodiment, the detecting mechanism includes a pair of detector modules disposed one on each side of the immobilizing mechanism.

Abstract: A method of analyzing a drilling fluid comprising subjecting a sample of the fluid to an XRF analysis technique and comparing the results obtained with a calibration model to determine the amount of one or more components of the fluid present in the sample. The method is particularly useful for determining solids in the fluid such as barite and can be combined with an FTIR technique which is sensitive to other components of the fluid. A PLS algorithm is used to construct the model from the spectra.

Abstract: There is described within a portable, battery-powered multiple filter infrared spectrometer consisting of a highly efficient optical system employing an infrared source with a chopper, from which IR energy passes through compound parabolic concentrators (CPC's) and is directed by a beamsplitter to the external sample, where the beam intersects with the sample via reflection and is returned through the CPC and beamsplitter to a stationary filter assembly and discrete detector array where the energy is converted to an A.C. (alternating current) signal. This current energizes an LED bar graph display for spectral identification. This method and apparatus is used to determine IR spectra of solids, liquids on a mirror, and gases in a container with a mirror to reflect light.

Abstract: An apparatus for detection of thermal neutrons includes a volume of gas which includes .sup.3 He. A wavelength shifting optical (WSO) fiber is disposed to receive ultra-violet (UV) photons generated by reactions between neutrons and .sup.3 He. UV photons are absorbed within the WSO fiber to produce longer wavelength fluorescence generated photons that propagate within the WSO fiber. A photodetector is disposed to receive fluorescence generated photons from at least one end of the optical fiber and provide an output signal corresponding to neutron detection.