Abstract: An improved detector dewar assembly comprised primarily of metal subassemblies, which is easily assembled, and leaves the included detector assembly more readily serviceable.

Abstract: A light absorbing matter is irradiated by light ranging from ultraviolet to infrared and absorbed light energy causes the matter to be raised to an excited energy state. The excited state is then locked by maintaining the temperature of the matter at a predetermined value. Light energy thus stored can be released for utilization by changing the value of the temperature from the predetermined value.

Abstract: An improved optical system for thermal imaging systems using wide field of view optics in conjunction with large detector arrays in which a detector cold shield, system aperture stop and scanning subassembly are placed in substantially the same location such that the size of the scanning optics is minimized and cold shielding efficiency is maximized.

Abstract: An infrared radiation gas analyzer for determining the concentration of an ingredient in a sample gas has a sample gas container for containing a sample gas at a temperature at which the ingredient the concentration of which is to be determined will emit infrared radiation in a range characteristic of the ingredient and a window for allowing the infrared radiation to escape from the container. A pair of filters is provided, one of the filters transmitting only radiation in the range and the other of the filters transmitting only radiation in a range near to the firstmentioned range. A disc with the filters thereon rotates in front of the window for passing the filters across the path of radiation escaping from the container.

Abstract: Resolution and sensitivity of photoconducting light sensitive devices vary nversely with temperature. Hence it is desirable to provide cooling means for photoconductive radiation detectors. One type of low temperature photoconductor is fabricated by placing the photomultiplier tube in a double-walled vacuum Dewar flask. In another type, the detector is mounted near a cryogenic projection, or cold finger, emenating from a refrigerator. In this case fabrication is critical, and great care must be exercised when the cryogenic cold finger is inserted in the Dewar well in order to avoid breakage. A different solution herein to the problem provides detector not as subject as prior devices to breakage of the Dewar detector wall.

Abstract: An infrared radiation gas analyzer for determining the concentration of an ingredient in a sample gas has a sample gas container for containing a sample gas at a temperature at which the ingredient the concentration of which is to be determined will emit infrared radiation in a range characteristic of the ingredient and a window for allowing the infrared radiation to escape from the container. An optical chopper is positioned outside the container for interrupting the radiation escaping from the container. A filter is positioned in the path of the radiation escaping from the container and transmits only radiation in the range. An infrared radiation detector is positioned for receiving the radiation passed by the filter and emitting a signal representative of the radiation received by the detector and which is representative of the concentration of the ingredient the concentration of which is to be determined in the sample gas.

Abstract: An infrared radiation gas analyzer for determining the concentration of an ingredient in a sample gas has a sample gas container for containing a sample gas at a temperature at which the ingredient the concentration of which is to be determined will emit infrared radiation in the range characteristic of the ingredient and a window for allowing the infrared radiation to escape from the container. An optical chopper outside said container interrupts the radiation escaping from the container. A pair of filters is positioned in the path of the radiation escaping from the container and spaced transversely of the path, one of the filters transmitting only radiation in the range and the other of the filters transmitting only radiation in a range near to the first mentioned range.

Abstract: A nondispersive, two-beam, infrared gas analyzer with two differently long measuring gas cells and differential detectors is improved by gilt detection cell interiors and absorbing rods in the detector cell which is in line with the shorter measuring gas cell. Adjustable absorption permits suppression of cross sensitivity errors.

Abstract: A transmission Dewar cooling chamber having a housing for supporting a semiconductor crystal therein within a temperature controlled environment. The housing has walls made partially of material transmissive to a preselected wavelength in order to allow the passing of a beam of electromagnetic radiation completely through the housing. In addition, mounting means are provided to move the housing in at least two dimensions. Securing the semiconductor crystal in place within the housing is a uniquely designed frame/mount arrangement which aids in establishing the temperature controlled environment for the crystal while also allowing the beam of electromagnetic radiation to pass completely through the crystal.

Abstract: A radiation receiver comprises an inner cylindrical part of insulating material having a closed end and an opposite end with a radially extending annular flange. At least one sensor is mounted on the inner part preferably on the closed end thereof and on its exterior. At least one conductor track lead provided on the inner part extending from the sensor on the exterior wall of the inner part and along the exterior of the flange. An outer cylindrical part having a closed end and an opposite open end has a rim surrounding the end which is engaged on the flange over the track at a location to leave an outer extending portion of the track extending outwardly from the exterior of said outer cylindrical part and along said flange. A glass solder seam seals the outer cylindrical part to the flange of the inner cylindrical part around the rim.

Abstract: A miniature, nonevacuated, detector refrigerator assembly for use in infrared imaging systems is described. The assembly incorporates a miniature Joule-Thomson laminar refrigerator which serves as the substrate for the detector subassembly, electrical leads, as well as the primary structural element of the assembly. The detector subassembly is positioned on the cold region of the refrigerator, surrounded by insulating material and capped by an optical window or filter as required. As a result, the detector is cooled while the contact pads used for connection to external devices are at the ambient temperature. A piece of high thermally conductive material may be placed in the vicinity of the detector subassembly so that during operation gases in the chamber surrounding the detector assembly will preferentially condense thereon rather than on the detector subassembly.

Abstract: A planar detector of a device for detecting corpuscular or electromagnetic radiation, utilizing the magnetic superheating properties of small superconducting particles in a magnetic field has its receiving surface subdivided into small superconducting detector elements of equal size and placed on a transparent body of a magneto-optically active material. The elements are illuminated from the rear with monochromatic, linearly polarized light, and can be observed via a crossed polarization filter to provide a radiation receiver of relatively simple design and high resolution.

Abstract: An infra-red radiation detector comprises an envelope in the form of a dewar (1,2) in which a vacuum space (12) is present between an outer wall (2) and inner wall (1) cooled by a cooling element (20). Gas molecules are gettered from the vacuum space (12) by at least one shaped molecular-sorbent porous body (10,10') having a major surface which fits onto and is bonded to a cooled surface (e.g. of a radiation shield 8) associated with the cooled inner wall (1). The shaped getter body (10,10') is secured (e.g. by epoxy adhesive) at its major surface to this cooled surface in a heat-exchange relationship so as to be cooled by the cooling element (20) during operation of the detector. The shaped getter body (10,10') is preferably a moulded annulus of synthetic zeolite material.

Abstract: An improved radiation detector is provided which comprises a thick film of thermistor material deposited upon a substrate of beryllium oxide, alumina or other suitable material having high thermal conductivity. The substrate is soldered to and supported by a heat sink. The detector films of this invention may be deposited in pairs, one element of each pair being shielded, to compensate for temperature fluctuations. An array of detector pairs of this invention may be constructed to measure laser beam intensity across the breadth of the beam to ascertain the intensity profile of the incident beam.

Abstract: A thermal coupler assembly mounted to the coldfinger of a cryogenic cooler which provides improved thermal transfer between the coldfinger and the detector assembly mounted on the dewar endwell. The thermal coupler design comprises a stud and spring-loaded cap mounted on the coldfinger assembly. Thermal transfer is made primarily through the air space between the cap and coldwell walls along the radial surfaces. The cap is spring loaded to provide thermal contact between the cap and endwell end surfaces.

Abstract: A detector for infrared radiation, having a multicell photosensor disposed at the top of a cold finger in an evacuated container, comprises a stack of annular ceramic layers coaxially surrounding the cold finger and serving as supports for several arrays of radially extending metallic strips screen-printed on respective layers in angularly offset relationship. The metallic strips are conductively connected to respective cells of the sensor to serve as output leads thereof. The conductive connections include axially extending metal pins spacedly surrounding the cold finger while being linked with the sensor cells by short, thin wires spanning an intervening annular gap.

Abstract: A shield for limiting the radiation received by electromagnetic energy radiation detectors to the radiation provided to the detectors by the optics of an electromagnetic energy detection system. The shield comprises a member transparent to a predetermined spectrum of radiation. An opaque thin film is deposited on a surface of the member, the thin film having apertures defined therein, the detectors viewing the optics through the member and the apertures. The thin film shields the detectors from electromagnetic radiation generated outside the field of view of the optics, thereby improving the sensitivity of the detection system. Virtually any desired thickness for the member may be used, thus allowing very close placement of the shield to the detectors and permitting use of very high density arrays.

Abstract: An optical system is disclosed for use with a radiant energy receiver which provides high cold shield efficiency and is compact; further the optical system is temperature tolerant to maintain focus with changes in temperature and wavelength without operator intervention. The optical system has primary utility in the infrared region of the spectrum and where a two dimensional array of detectors senses the infrared radiant energy or flux from the scene of interest. The optical system is comprised of a window for environmental protection and two objective mirrors for folding and focusing the scene of interest on a first focal plane.

Abstract: A shield for limiting the radiation received by individual detectors within a detector array of an electromagnetic radiation detection system to the radiation provided to the detectors by the optics of the system. The shield comprises a member of etchable glass having apertures formed therein, the position of the aperture edges being in predetermined relation to the edges of the detectors for shielding the detectors from electromagnetic radiation generated outside the field of view of the optics.

Abstract: A processor apparatus is provided in which a blackbody radiator having a constant planar energy flux characteristic is placed in opposition to semiconductor material. The blackbody source produces a constant planar energy flux to uniformly heat the material. The source is heated to a sufficiently high temperature for a sufficient time to anneal or activate a semiconductor wafer or to epitaxially regrow a thin epitaxial film. The processor is operated by accomplishing the steps of presenting a blackbody radiator in opposition to semiconductor material to be thermally treated, radiatively heating the material to a sufficiently high temperature for a sufficient time to accomplish the desired process result, and cooling and removing the material. In the interval between presentation of successive samples of the material to the source, the source may be shuttered or idled to reduce energy consumption.

Abstract: A dark field infrared telescope. Energy from an infrared scene is focused by a lens (10) onto a thermoptic modulator (12) comprising an optical structure (16) containing a thin film of vanadium dioxide disposed to form the faceplate of a conventional cathode ray tube. The modulator, normally nonreflecting of infrared energy, may have reflecting spots written at selected coordinates thereon by an electron beam from the cathode ray tube. A reflecting spot written on the modulator optically couples a selected element of the scene imaged on the modulator to an infrared detector (52) maintained at low temperature. A retroreflecting mirror (30), cold spectral filter (46), field lens (47), cold field stop (48) and cold pupil stop (50) are provided ahead of the detector to produce a low background flux cavity with the detector at one end and the retroreflecting mirror at the other. In its unswitched state, the modulator is nonreflecting and the scene image is not coupled to the detector.

Abstract: A detector device for limiting background noise detected by a cooled infrared detector. In order to delimit the angle of view of the detector, the device comprises a reflecting deposit formed externally of the cooling device on one face of a transparent element interposed on the receiving path. The deposit can be located on the outer face of the window of the cooling device within which the detector is mounted on a cold table forming a spherical mirror. The complete assembly is optically combined so as to ensure that the radiation issuing from the detector outside the angle of view is returned to the detector.

Abstract: A processor apparatus is provided in which a blackbody radiator having a constant planar energy flux characteristic is placed in opposition to semiconductor material. The blackbody source produces a constant planar energy flux to uniformly heat the material. The source is heated to a sufficiently high temperature for a sufficient time to anneal or activate a semiconductor wafer or to epitaxially regrow a thin epitaxial film. The processor is operated by accomplishing the steps of presenting a blackbody radiator in opposition to semiconductor material to be thermally treated, radiatively heating the material to a sufficiently high temperature for a sufficient time to accomplish the desired process result, and cooling and removing the material. In the interval between presentation of successive samples of the material to the source, the source may be shuttered or idled to reduce energy consumption.

Abstract: An infrared radiation detecting system comprises a detector element 13A forming part of a detector 13 incorporating a cold shield 14 and an optical system 12, 15, for imaging infrared radiation from a field of view O onto a real image surface 19 spaced from the detector element 13A and relaying the image I from the surface 19 to the detector element 13A is provided with a graticule 20 having markings which are reflective to infrared radiation emitted by the detector 13. Graticule 20 is located at the image surface 19 so that the graticule markings are imaged onto the detector element 13A in superimposition with the infrared radiation from the field of view O.

Abstract: The chopped infrared radiation leaving a measuring and sample gas chamber in an infrared gas analyzer is passed through and into two serially arranged detection chambers which are connected to a differential pressure chamber with capacitive pickup. The chambers are filled with gas of the type whose concentration, in the sample gas, is to be detected. One of the detector chambers contains a thin black wire, a diaphragm on the outside may shield an adjustable portion of that wire from radiation. The wire absorbs all radiation it intercepts and heats the environment.

Abstract: A passive infrared detection system which exhibits a consistent optical aperture and sensitivity over different operating ranges. The system includes a mirror assembly having a plurality of spherical segments arranged in two or more ranks, each corresponding to a different operating range. Each mirror segment is disposed at its respective focal length from a detector, and is of a size and configuration to provide an intended optical aperture to achieve uniform detection sensitivity irrespective of the range of the target.

Abstract: The invention relates to a thermal coupling assembly between the cold fin of a cryogenic cooler and a dewar enclosed detector for use at infrared and far infrared frequencies. The coupling provides excellent thermal coupling without solid or even liquid contact between the cold finger and the detector, so that no strain or vibration is transmitted therebetween.

Abstract: An absorbed dose water calorimeter that takes advantage of the low thermal diffusivity of water and the water-imperviousness of polyethylene film. An ultra-small bead thermistor is sandwiched between two thin polyethylene films stretched between insulative supports in a water bath. The polyethylene films insulate the thermistor and its leads, the leads being run out from between the films in insulated sleeving and then to junctions to form a Wheatstone bridge circuit. Convection barriers may be provided to reduce the effects of convection from the point of measurement. Controlled heating of different levels in the water bath is accomplished by electrical heater circuits provided for controlling temperature drift and providing adiabatic operation of the calorimeter. The absorbed dose is determined from the known specific heat of water and the measured temperature change.

Abstract: An infrared detector and envelope arrangement for the detector have a novel mount (21,22,23,24) for a Joule-Thomson or other cooling element (10). The mount is a single unit (21,22,23,24) which includes an inner part (23) on which the cooling element (10) is mounted e.g. via an adaptor (30). The cooling element (10) is secured in a dewar (1,2) of the envelope arrangement by attaching an outer part (21,22) of the mount (21,22,23,24) to a dewar mount (13) e.g. by bolts (22). These inner and outer parts (23 and 21,22) which may have overlapping flanges (43,37 and 21, see FIGS. 2 to 6) are elastically coupled together by a resilient part (24) of the mount (21,22,23,24). The resilient coupling reduces movement and strain of the inner dewar wall (1) caused by movement of the cooling element both during assembly and use of the detector.

Abstract: An infrared detector assembly comprising a substrate of suitable material such as sapphire, an infrared detector array attached to the substrate, a cold shield attached to the detector array, and an optical microphonics filter attached to the cold shield is disclosed. The optical microphonics filter includes a substrate of material having its major surfaces coated with layers of thin film coatings for passing a preselected frequency band, and a metalization for reflecting spurious energy impinging thereon thereby shielding the filter's substrate and coatings therefrom.

Abstract: A passive infrared alarm device evaluates the changes in infrared radiation level of a monitored room or a monitored portion of a room for alarm purposes. In accordance with the invention, an infrared sensing element is employed toward which an optical reflector directs infrared radiation emanating from one or more angles in a room to be monitored. An infrared filter is mounted in the path of the reflected infrared radiation before such radiation reaches the sensing element. The infrared filter is designed to absorb infrared radiation below a predetermined minimum wavelength, and additional means is provided for partially absorbing infrared radiation below the predetermined minimum at the reflector.

Abstract: A gas analyzer of the non-dispersive infrared type is described. An infrared beam passing through a sample cell containing a gas mixture to be analyzed is detected. The resulting electrical signals are processed to produce an output indicating the concentration of the constituents of the gas mixture in the sample cell. The gas analyzer includes provision for temperature stabilizing both a rotary filter wheel and the detector, and for compensating the output of the signal processor for variation in the absorption characteristics of gas with temperature. The emissivity characteristic of the infrared energy source substantially compensates for wavelength dependence of the detector response. The motor drive for the rotary filter wheel is servo-controlled in accordance with synchronizing pulses developed directly from the detector output.

Abstract: Disclosed is an optical system for use in a multispectral scanner of the type used in video imaging devices. Electromagnetic radiation reflected by a rotating scan mirror is focused by a concave primary telescope mirror and collimated by a second concave mirror. The collimated beam is split by a dichroic filter which transmits radiant energy in the infrared spectrum and reflects visible and near infrared energy. The long wavelength beam is filtered and focused on an infrared detector positioned in a cryogenic environment. The short wavelength beam is dispersed by a pair of prisms, then projected on an array of detectors also mounted in a cryogenic environment and oriented at an angle relative to the optical path of the dispersed short wavelength beam.

Abstract: An improved Dewar assembly for infrared detectors is disclosed. Vacuum tight feed-throughs are partially embedded in the inner flask with exposed portions on both sides of a vacuum seal.

Abstract: A cooled echelle grating spectrometer for detecting wavelengths between one micron and fifteen microns. More specifically, a spectrometer is disclosed having a cross-dispersing grating for ordering infrared energy, and an echelle grating for further ordering of the infrared energy. Means are disclosed to direct infrared energy to the cross-dispersing grating and then to the echelle grating. Ordered radiation from the echelle grating is sensed by a detecting means. Means are also disclosed for cooling the cross-dispersing grating, the echelle grating and the detecting means so that background radiation can be minimized. In a specific embodiment the cross-dispersing grating and echelle grating are in separate enclosed volumes having access to each other through a single intermediate aperture, reflected energy from the cross-dispersing grating being focused so as to pass through the intermediate aperture and then collimated and directed to the echelle grating for further ordering.

Abstract: An assembly for transferring heat at cryogenic temperatures across an interface space between a relatively fixed refrigerated cold finger and a relatively movable Dewar vacuum flask having an infrared detector array mounted therein. The interface assembly is formed of two opposing thermal conducting plates which are spring loaded so as to be in intimate contact with both the end face of the cold finger and a face of the opposite side of the mounting element for the detector array in the Dewar vacuum flask. A flexible thermal conductor element surrounds the spring and is securely connected to the opposing plates to complete the thermal conduction path between the flask and the cold finger. A first preferred embodiment of the assembly utilizes a bellows shaped flexible thermal conductor which allows the plates to make intimate contact with their corresponding faces even though the faces may be oriented in non-parallel configurations.

Abstract: A metallic block has a conical measuring-light inlet port and a conical reference-light inlet port formed therein. The ports intersect at a light sensor. The inlet ports are closed by respective multilayer interference filters. Temperature control means, which may be responsive to the light sensor output, maintains the metallic block, and thus the filters and sensor, at a fixed temperature.

Abstract: The invention provides an elastic interface between a cooler dewar and an electronic cold finger which utilizes multitudinous conduction paths consisting of specialized bent fibers.

Abstract: A scanning radiometer having a series of laminations forming a tightly bonded sandwich structure each being electrically insulated from adjacent ones thereof, said series including a thermometric or thermo responsive material, a heat pump functioning material, a heat sink functioning material, and an insulator functioning material, and in which the thermo responsive material is formed of a set of matrix of thin metal alternately with absorptive or blackened portions, each forming opposite arms of a Wheatstone bridge.The use of the term "thermoelectric or thermoresponsive material" designates a metallic or other electric resistor whose resistance is temperature sensitive and when measured, is an indicator of its temperature. "Heat pump functioning material" is a thermoelectric device that tranfers or "pumps" heat from one of its two surfaces to the other when an electric current is supplied to its terminals.

Abstract: A gas-sample collection device is disclosed for matrix isolation of individual gas bands from a gas chromatographic separation and for presenting these distinct samples for spectrometric examination. The device includes a vacuum chamber containing a rotatably supported, specular carrousel having a number of external, reflecting surfaces around its axis of rotation for holding samples. A gas inlet is provided for depositing sample and matrix material on the individual reflecting surfaces maintained at a sufficiently low temperature to cause solidification. Two optical windows or lenses are installed in the vacuum chamber walls for transmitting a beam of electromagnetic radiation, for instance infrared light, through a selected sample. Positioned within the chamber are two concave mirrors, the first aligned to receive the light beam from one of the lenses and focus it to the sample on one of the reflecting surfaces of the carrousel.

Abstract: An improved ferroelectric imaging system comprises a chopper, lens system, ferroelectric detector matrix, anistropic heat sink, switching matrix, temperature controlled heat sink, drive and read out electronics, video processor, and display. The chopper interrupts infrared energy emanating from a scene, and the lens system focuses the chopped infrared energy on the ferroelectric detector matrix which produces electrical signals representative of the infrared energy impinging thereon. The signals are read out by the drive and read out electronics whose action is synchronized with the chopper action, processed in the video processor and displayed by the display. The ferroelectric detector matrix is a plurality of detector capacitor elements whose lower plates are metal pads formed on the lower surface of the dielectric which is a wafer of ferroelectric material.

Abstract: A closed loop apparatus for spraying coolant against the back of a radiation target. The coolant is circulated through a closed loop with a bubble of inert gas being maintained around the spray. Mesh material is disposed between the bubble and the surface of the liquid coolant which is below the bubble at a predetermined level. In a second embodiment no inert gas is used, the bubble consisting of vapor produced when the coolant is sprayed against the target.

Abstract: The wave length of an infrared, semiconductor laser diode having an output frequency that is dependent on the diode temperature is maintained substantially constant by maintaining the diode temperature constant. The diode is carried by a cold tip of a closed cycle helium refrigerator. The refrigerator has a tendency to cause the temperature of the cold tip to oscillate. A heater diode and a sensor diode are placed on a thermal heat sink that is the only highly conductive thermal path between the laser diode and the cold tip. The heat sink has a small volume and low thermal capacitance so that the sensing diode is at substantially the same temperature as the heater diode and substantially no thermal lag exists between them. The sensor diode is connected in a negative feedback circuit with the heater diode so that the tendency of the laser diode to thermally oscillate is virtually eliminated.

Abstract: A cryogenic container with low thermal losses for infra-red detecting devices, with integrated feed-through connections, wherein said container consists of two elements adapted to have their outer walls joined, the two walls having two edges with surfaces facing one another to define an annular zone arranged to receive vacuum sealed feed-through connections in the form of a substrate on which a multiplicity of conductors is formed by micro-circuitry techniques. The conductors extend through the annular zone and project both inward and outward of the outer wall. A flexible element is provided for contacting an active element inside the cryostat with the conductors. The flexible element consists of a layer of plastic material supporting a multiplicity of conductive tracks.

Abstract: Bolometer cooled to a very low temperature, wherein the sensitive element has a very low thermal capacity and, for this purpose, a semiconductor crystal extended on two faces by beams made of the same material, but of smaller section, which have been metallized. These metallized beams, wherein the volume of crystal has been reduced to a minimum by their very small section, directly or indirectly provide the thermal link with the cryostat and the electrical link with the measuring circuit making it possible to eliminate all welds using bonding metal on the side of the crystal which forms part of the sensitive element. In a preferred mode of embodiment, the thermal substrate thermally linked to the crystal is a piece of monocrystalline diamond.

Abstract: An optical limiter includes two bandpass filters whose narrow passbands are at least partially overlapping at low light levels. One of the two filters is well heat-sunk while the other is not. When the input light level exceeds a threshold level, heating causes the passband of the thermally isolated filter to shift relative to the passband of the heat-sunk filter. High level light self-limits or attenuates itself by virtue of the filter passband mismatch that occurs.

Abstract: The invention is a temperature stabilizing device employing a liquid crys wherein the crystal is itself stabilized to provide a thermal viewing element.

Abstract: The invention relates to a method for the operation of an instrument subjected to a radiation, which is protected from the harmful influence of the radiation by means of an auxiliary medium and/or swinging in of a protective shield between source of radiation and instrument.The invention relates further to an apparatus for carrying out this method.

Abstract: A balancing radiometer for measuring the intensity of incident electromagnetic radiation comprises: a pair of identical sensors, each including a thermally conductive substrate, at least one surface of the substrate being comprised of an electrically insulating material, and means disposed on the one surface for resisting the flow of electric current and absorbing incident radiation; means for shielding one of the two sensors from the radiation source, the other sensor being unshielded; means disposed in thermal conducting relation with the substrate of the shielded sensor for providing a first signal proportional to the temperature of the shielded sensor; second means disposed in thermal conducting relation with the substrate of the unshielded sensor for providing a second signal proportional to the temperature of the unshielded sensor; means for comparing the first and second signals; variable power supply means responsive to the signal comparing means; means for connecting the power supply means to the shi

Abstract: A method and associated apparatus for quantizing radiation beams by optical diffraction including the steps of, and associated apparatus for, reflecting a majority of the energy in an incident radiation beam, optically diffracting portions of the non-reflected incident radiation beam to provide quantized radiation beam portions of reduced intensity, and individually detecting each of the quantized radiation portions. Advantageously, the detected radiation beam portions are converted to electrical signals which may be processed for display, as desired.