Abstract: Aiming system for firearms of the type for use when a target is obscured for example by darkness or camouflage include a sighting arrangement which comprises an imaging device of sufficiently small size to be carried on the firearm. These imaging devices consequently have small apertures and low resolution and are therefore of limited value. The aiming system disclosed herein has an imaging device remote from the firearm which forms a background image of a given field-of-view, the image being displayed on a screen. The system includes a second imaging device carried by the firearm and having a smaller field-of-view corresponding to the line-of-sight of the firearm. The images produced by both imaging devices are correlated by a correlator and a sight-mark is generated in the background image to indicate the line-of-sight of the firearm when correlation is obtained.

Abstract: Correlation is used to enhance the temporal resolution capability of incident energy detectors for high bandwidth signals. Such enhanced resolution is attained by using a primary response of the detectors, which may be weak but which accurately replicates the temporal waveshape of the incident energy pulse. A secondary response of the detectors, which is delayed from and more powerful than the primary response, but does not track the incident energy pulse as well as the primary, is correlated with the primary response. The secondary response is preferably passed through an inverse matched filter to provide a pulse more faithfully following the incident energy pulse prior to correlation with the primary response. Circuitry is provided for performing the enhancement, and a modulating device is used to permit the detector to respond to long-duration incident energy.

Abstract: A luminescence detecting device including a luminescence sensitive member made of a transparent resin or the like and containing at least two different kinds of organic phosphors dispersed therein. The first organic phosphor is operative to absorb fluorescence from incident radiation such as the index phosphor stripes from a reflex color cathode ray tube, and has a response spectrum which overlaps with the wavelength range of the incident fluorescence. The first phosphor is designed to emit fluorescence in a higher wavelength range upon excitation by the incident fluorescent radiation. The second phosphor is responsive to the fluorescence emitted by the first phosphor since the spectra of the two phosphors overlap. The second type of organic phosphor emits its own range of fluorescence in a particular wave band and can be detected by a luminescence sensing portion of the device to provide a signal which can be used to control the operation of the cathode ray tube.

Abstract: Apparatus is provided for optically measuring scalar irradiance or incident flux of radiant energy and for optically measuring naturally occurring chlorophyll fluorescence or upwelling radiance in a parcel of water in a natural setting. From a comparison of the two measurements, rate of primary photosynthetic production is calculated by appropriately programmed computer means. Readout means are provided to indicate the rate of primary production. Further, concentrations of chlorophyll that generate the primary production are also determined by means of the apparatus of this invention. The method of this invention, employing measurement instruments of the type disclosed, enables the determination of concentrations of chlorophyll and primary production in parcels of water.

Abstract: An optical probe mounting device for the insertion end of a fluorescence measuring optical probe which facilitates mounting on a biological reactor vessel window fitting. The device consists of a rigid hollow cylinder sized to closely receive the probe and to closely slide within the interior of the fitting. A quartz window seals the insertion end of the cylinder to allow passage of ultraviolet light without attenuation. A flange is sealingly affixed to the cylinder which permits the cylinder to extend a predetermined distance into the vessel. An O-ring extends around the cylinder or a face seal is used on the rear flange of the well, thereby providing a seal upon insertion of the device into the fitting.

Abstract: A passive device for measuring environmental radioactivity employs three radiation detectors enclosed in a small shielded housing. A first radiation detector generates a first signal responsive to an amount of radioactivity produced over a period of time by radioactive gas diffused in the volume of air inside the housing. The first radiation detector includes at least one thermoluminescence dosimeter mounted in close proximity to an electret. A second radiation detector generates a second signal responsive to an amount of environmental gamma radiation over the period of time, and also includes at least one thermoluminescence dosimeter. A third radiation detector generates a third signal indicative of an amount of fading of the second signal over the period of time, the third radiation detector also including at least one thermoluminescene dosimeter having an initially predetermined third signal.

Abstract: A method and apparatus for interrogating a transparent photostimulable luminescent screen is characterized by positioning the screen with respect to a virtual point source of interrogating radiation such that the scanning interrogating radiation passes through the screen along the same paths as did the imaging beam.

Abstract: In an instrument for the detection of ultra-violet radiation, visible light or infrared radiation an electric coupling is known, which comprises a photo-diode of silicon or germanium, a measurement resistor, over which generated photo-electric current generates a voltage, and a voltmeter with low leakage current for measuring the voltage generated. For rendering possible a less expensive, simpler and safer structural design than the designs known and commercially available, it is proposed that the measurement resistor R.sub.A and the calibrated voltmeter V each are connected in parallel over the photo-diode.

Abstract: The capacitive bolometer comprises a detection capacitor having a first-order phase transistion ferroelectric material between two electrodes. The detection capacitor operates during a detection step and a subsequent readout step. During the detection step, a preselected electric field is applied to the detection capacitor to maximize its sensitivity to temperature. A second electric field is applied to the capacitor during the readout step in order to increase responsivity of the detection cell. The detection cells according to the invention can be assembled into disclosed detection arrays.

Abstract: An infrared detector has an infrared detector element (2) mounted at a first part (11) of a housing (1), a Joule-Thomson cooling element (3) accommodated in a second part (12), and an infrared transmissive window (15) at the front of the housing (1). A compact, space-saving and light weight structure with improved optical efficiency is obtained. The core of the Joule-Thomson cooling element (3) forms a third part (13) of the housing (1), and these second and third parts (12 and 13) of the housing extend towards the front of the detector. The cooler core (13) which may carry a cooled filter (25) has a hollow shape or is otherwise infrared transmissive in front of the detector element (2) and can direct incident radiation (50) towards the detector element (2). For this purpose the inner surface of the hollow core (13) may carry a reflective conductor pattern (18,19) which also provides electrical connections for the detector element (2).

Abstract: A radiation image recording and reproducing system comprises recording apparatuses for recording image information on a stimulable phosphor sheet, read-out apparatuses for photoelectrically detecting the image information by scanning the stimulable phosphor sheet by stimulating rays, and a reproducing apparatus for scanning a recording sheet by light modulated with the image information thus read out to reproduce the image information on the recording sheet. The reproducing apparatus is provided with a plurality of trays, and the recording sheet with the image information reproduced thereon is distributed and fed into any one of the trays.

Abstract: A fluorescence imaging system. A light source irradiates an object to be viewed. The irradiated object is imaged through a beam-splitting system to form individual displaced images of the object. The displaced images are further filtered in a filter having a frequency passband different from the other filters. The filtered images are imaged on a detector. The same image point of each image is detected and converted into an electrical signal. A circuit means is provided to receive the signals of each common image point, and weight the same. The weighted signal represents an image point pixel. The weighted pixels are displayed as an image of the object having improved contrast.

Abstract: A method and apparatus for multiplexing signals from electromagnetic radiation detectors is disclosed. The apparatus (10) includes a plurality of elemental detectors (16-32) each of which is being operable to generate an output in response to receipt of electromagnetic radiation. Also provided is a circuit for frequency division multiplexing the output of said elemental detectors.

Abstract: In conventional methods of quantitative hydrocarbon analysis in gaseous sles by means of infrared transmission, systematic inaccuracies may be found which are caused by changes in the composition of the components contained in the sample. Such inaccuracies typically amount to 10 to 30% of the measured value, with occasional rises of up to 100%. In order to eliminate this disadvantage the invention proposes that for determining the total mass of gaseous and condensed hydrocarbons radiation be used with a frequency band whose integral infrared absorption has approximately the same value for each of the main hydrocarbons present.

Abstract: An apparatus and method for measuring the thickness of thin basal coatings on work pieces. The apparatus comprises a beta backscatter type measuring instrument including a work piece positioning system to permit the precise positioning of a coated work piece surface to radiation in a repeatable, non-destructive, non-contacting position with respect to the radiation source.

Abstract: The camera includes a chip of infrared detectors disposed in lines and a processing chip. The latter comprises integrators for integrating the output currents of the detectors, controlled by an automatic gain control loop for reducing the dynamic of the signal, delay lines, a summator for each line of detectors, error correction devices for reducing the fixed spatial noise errors, and a multiplexer receiving the signals associated with the various lines of detectors and furnishing a signal to a display device.

Abstract: A position transmitter which determines the point of incidence of a light or particle beam on a sensor array, and the output signal of which gives the point of incidence in a digital code. The position transmitter comprises a sensor array having diodes which are arranged on a substrate and are connected at least partly to each other as well as to a digital bus, of which a part of the array generates electron-hole pairs if the light or particle beam strikes, and another part of the diode array arranged in accordance with the desired code is switched off in its function.

Abstract: The nuclear moisture-density gauge of the present invention employs a low activity neutron radiation source and a low activity gamma radiation source. In order to achieve more accurate density measurements at the relatively low count rates which results from the use of a low activity gamma source, the present invention is provided with means for generating a correction signal which is a function of the moisture content of the test material and which represents the amount of gamma radiation emitted from the test material resulting from the neutron capture reaction due to the presence of neutron capture elements, such as hydrogen, present in the test material. This correction signal is applied to the uncorrected density signal obtained from the gauge to thereby obtain a corrected density measurement which is unaffected by background gamma radiation caused by the presence of neutron capture elements in the test material.

Abstract: A spark discharge trace element detection system is provided which includes a spark chamber including a pair of electrodes for receiving a sample of gas to be analyzed at no greater than atmospheric pressure. A voltage is provided across the electrodes for generating a spark in the sample. The intensity of the emitted radiation in at least one primary selected narrow band of the radiation is detected. Each primary band corresponds to an element to be detected in the gas. The intensity of the emission in each detected primary band is integrated during the afterglow time interval of the spark emission and a signal representative of the integrated intensity of the emission in each selected primary bond is utilized to determine the concentration of the corresponding element in the gas.

Abstract: A scintillation detector is provided which has a scintillation member comprised of a substance which converts energy received in the form of an ionizing particle to light. The scintillation member, such as a thallium-activated alkali halide crystal, is sealed in a housing containing an atmosphere which is substantially non-reactive to the scintillation member at temperatures ranging from about 100.degree. C. to about 250.degree. C. Examples of suitable atmospheres include the noble gases including helium, neon argon, krypton, xenon and radon; nitrogen; carbon dioxide, a vacuum, and other atmospheres, such as mixtures of these or air which has been substantially depleted of oxygen. Processes for the manufacture of the detector are taught where the scintillation member is encapsulated in a non-reactive atmosphere such as ones listed above. Alternatively, the reactive atmosphere can be washed from the housing or the sealed housing can be evacuated and refilled with a non-reactive atmosphere.