Abstract: This invention relates to a compact cavity ring down spectrometer for detection and measurement of trace species in a sample gas using a tunable solid-state continuous-wave mid-infrared PPLN OPO laser or a tunable low-power solid-state continuous wave near-infrared diode laser with an algorithm for reducing the periodic noise in the voltage decay signal which subjects the data to cluster analysis or by averaging of the interquartile range of the data.

Abstract: A gas sensor comprises a cavity for containing a gas, means for generating radiation which is transmitted through the cavity and includes one or more wavelengths which is absorbed in use by a gas to be detected; and a detector for detecting radiation which has passed through the cavity. The walls of the cavity are sufficiently reflective to the radiation that the cavity is substantially uniformally illuminated with the radiation.

Abstract: Systems and methods for long range recognition and identification of objects and targets, and, more particularly, to long range imaging systems that include the use of mid-wave infrared laser illumination technology are provided. In particular, mid-wave infrared laser illuminated imaging systems and methods are disclosed for addressing, among other things, the problems associated with long range, day or night observations of targets through various obscurants (e.g., fog, haze, rain, smoke). Such systems may be configured to operate in either a single, active illumination mode or in a dual, active/passive mode.

Abstract: An apparatus for analyzing, identifying or imaging an object including a source of pulsed signals in the range of frequencies from 100 GHz to over 2 THz focused on the object; and a detector for acquiring spectral information from signals reflected from the object and using a heterodyning process to generate an electrical signal representative of some characteristics of the object. The source of pulse signals and the detector is a photoconductive switch activated by a pulsed laser beam.

Abstract: Provided is a solder material test method that reduces labor and time and is preferred in operation hygiene. Detected are a first intensity at a particular wave number of infrared radiation reflected from a test-sample solder material by illuminating light to the test-sample solder material and a second intensity at the particular wave number of infrared radiation reflected from a comparative-sample solder material by illuminating light to the comparative-sample solder material. Depending upon the first and second intensities detected, intensity differences and ratios are determined. Those may be absorbance differences or intensities of between an infrared radiation absorbance to test-sample solder material and an infrared radiation absorbance to comparative-sample solder material. From the intensity difference, intensity ratio, absorbance difference and absorbance ratio, the test-sample solder material is tested for deterioration degree relatively to the comparative sample.

Abstract: Systems for THz transmission using new types of THz waveguides with low loss, negligible group velocity dispersion and structural simplicity are described herein. The THz system incorporates the use of a waveguide with two or more substantially parallel conductive elements which may enable many new THz sensing applications. It is now possible to direct the THz pulse inside of containers or around corners, where line-of-sight optics are not practical. Moreover, the systems allow use of either radially polarized or linearly polarized THz antennas. The disclosed systems are compatible with existing terahertz generation and detection techniques.

Abstract: An analysis apparatus and analysis method are provided for obtaining information on a sample from change in propagation state of a magnetic wave caused thereby, with less influence of frequency characteristics on the detection unit side. The analysis apparatus comprises a generating unit for generating a terahertz wave, a signal-making unit for making a code pattern, a delaying unit for delaying the code pattern produced by the signal-making unit, a band-diffusing unit for diffusing a band of the terahertz wave by modifying the phase of the terahertz wave generated by the generating unit in accordance with the code pattern produced by the signal-making unit, a detecting unit for detecting the terahertz wave, and a band-restoring unit for restoring the band by modulating the phase of the terahertz wave in accordance with the code pattern being output from the delaying unit before detection by the detecting unit.

Abstract: A method of analyzing a remotely-located object includes the steps of inducing a volume of an ionized ambient gas to emit pulsed terahertz radiation directed toward a targeted object by focusing an optical pump beam in the volume and ionizing another volume of the ambient gas to produce a sensor plasma by focusing an optical probe beam in the other volume of ambient gas. The interaction, in the sensor plasma, of the focused optical probe beam and an incident terahertz wave, which is produced by the targeted object reflecting, scattering, or transmitting the pulsed terahertz radiation, produces a resultant radiation. Detecting an optical component of the resultant radiation emitted by the sensor plasma facilitates detection of a signature of the targeted object imposed onto the incident terahertz radiation.

Abstract: A spectrometer system for providing information about a target with terahertz radiation. The system may receive incident radiation from the target through fore optics, a slit aperture, secondary optics and a dispersive element which images a slit on an array of terahertz sensitive detectors. The detectors may include uncooled sensors. Each sensor may be connected to its own micro antenna. The array of detectors may be situated proximate to the dispersive element so that radiation from the element may be dispersed according to wavelength to the respective detectors optimally sensitive to the various respective wavelengths. Detector signals indicating the impingement of terahertz radiation may provide information for identifying a material of the target.

Abstract: A system and method of monitoring with temperature stabilization. The system can include a housing operably connected to a fiber optic cable that provides a light wave thereto, a relay optic for receiving the light wave and being positioned in the housing, a radiation device for processing or producing radiation in the frequency range of 10 GHz to 100 THz from the light wave and being positioned in the housing, a temperature sensor in thermal communication with the housing, and a thermal management device in thermal communication with the housing where the thermal management device adjusts a temperature within the housing based on temperature conditions measured by the temperature sensor. Other embodiments are disclosed.

Abstract: A process for characterizing the phase of an organic material in a thin film comprises employing a reference spectrum library for potential phases, subjecting the film to a vibrational spectroscopy measurement to obtain a resulting spectrum; and comparing the resulting spectrum to those in the reference library to characterize the phase of the organic material.

Abstract: A time-domain pulsed spectroscopy apparatus which has a pulsed laser light source; a splitting unit to split pulsed laser light; a pulsed-light emitting unit; a detector; a sample holder; and a sample-unit entrance and exit optical systems; wherein the time-domain pulsed spectroscopy apparatus further comprises: at least one optical-path-length varying unit for setting a photometric range; at least one optical delay unit for the wave form signal measurement; and, at least one gate member to pass or block the pulsed light to a reflector.

Abstract: A method and system for detecting concealed weapons and explosives by imaging THz scenes using conventional optics and detectors is provided. Photon fields with two different wavelengths can be sent through a chopper and towards a wavelength-selective mirror. A light beam with a wavelength in the visible or IR range is sent toward a visible photon array detector. Similarly, light beams with wavelengths in the THz range can be sent towards a target, which are reflected and/or absorbed by objects in the target. The reflected or transmitted light continues on through an optional filter to remove background light, then into a non-imaging detector. The visible photon array detector can be coupled with the non-imaging detector, which will register an image of the scene that is illuminated by the THz photons.

Abstract: A detector arrangement for electromagnetic radiation has at least an absorbing element and a cantilever sensor which are in operational connection with each other, so that the sensor is bendable in response to electromagnetic radiation absorbed by the absorbing element. The arrangement further includes an interferometer for measuring bending of the cantilever sensor. In a method for measuring electromagnetic radiation, electromagnetic radiation is directed on to the absorbing element and thereby bending of the cantilever sensor is caused. Bending of the cantilever sensor is measured with an interferometer. The cantilever sensor can be a door-like flap made of silicon, attached to one side of a frame of silicon.

Abstract: The present invention relates to a device for imaging a turbid medium (130, 132; 184) comprising: means (110; 134, 138, 140, 142, 144, 146) for optically scanning a predefined maximum area of a scanning plane (102; 104) for acquisition of imaging data, means (134, 136; 206, 208, 210) for detection of an outer contour of the turbid medium, means (112, 120, 122) for controlling the optical scanning such that a sub-area of the maximum area is scanned that is smaller than the maximum area and that covers the outer contour.

Abstract: The invention relates to improved terahertz radiation sources and associated methods. A terahertz radiation source is described, comprising: an emitter (202) comprising a semiconductor material (12); a pair of electrodes (204a,b) adjacent a face of said semiconductor, said pair of electrodes defining a gap between said electrodes; a pulsed light source input for illuminating said semiconductor to excite photo-carriers in said semiconductor to generate terahertz radiation; and a radiation collector (212) to collect said terahertz radiation; and wherein said radiation collector is disposed on the same side of said semiconductor as said electrodes. A related method of providing terahertz radiation is also described.

Abstract: A sensing device includes a transmission path, an electromagnetic-wave input unit through which an electromagnetic wave enters the transmission path, an electromagnetic-wave detector configured to detect the electromagnetic wave propagating through the transmission path, and a bent portion provided in the transmission path. The electromagnetic wave propagates through the transmission path while radiating to the periphery of the transmission path. The bent portion is provided in the transmission path for allowing an interaction to occur between a test subject and the electromagnetic wave in the transmission path. When the test subject is positioned relative to the bent portion, the electromagnetic-wave detector detects a change in the state of the electromagnetic wave caused by the interaction occurring between the test subject and the electromagnetic wave in the bent portion. The detected information provides a basis for obtaining information on the test subject.

Abstract: A system and method for determining a level of effective residual ink concentration (ERIC) in a piece of recycled paper. The piece of paper is illuminated with a beam of radiation and an amount of the beam of radiation reflected and transmitted by the piece of paper is measured. The level of ERIC is determined as a function of the reflected and transmitted radiation.

Abstract: Method and apparatus for irradiating a sample with Terhertz radiation and detecting non-specular radiation in order to characterise the internal structure of the sample. Terahertz radiation specularly reflected from the surface is minimised so that it does not mask the weaker signal originating from the internal structure of the sample.

Abstract: Systems and methods for addressable field enhancement microscopy are provided. In an embodiment, a nanoscale array of islands may be illuminated with an electromagnetic signal and addressed to differentiate signals from different islands of the nanoscale array. The differentiated signals originating from illuminating the nanoscale array may be applied to microscopy of a specimen.

Abstract: A coherent radiation imaging system that produces digital images with a reduced amount of speckle. Radiation from a long coherence length source is used to form an image of a sample. The output coherent wave is temporally divided into a plurality of wavelets. The spatial phase of each wavelet is then modulated a known and different amount. Each phase modulated wavelet illuminates the sample and is perturbed by its interaction with the sample. A spatial phase map of each perturbed wavelet is then created and converted to a sample image with an image reconstruction program. The plurality of sample images thus formed is statistically averaged to form a final averaged image. The high frequency speckle that is not optically resolvable tends to average to zero with continual statistical averaging, leaving only the optically resolvable lower frequency phase information.

Abstract: Diamond-like carbon based energy conversion devices and methods of making and using the same are disclosed. Such devices may include a surface for detection of infrared photons. Such a surface may include at least one metal cone and a diamond-like carbon layer disposed on the at least one metal cone. The at least one diamond-like carbon-coated metal cone is thus configured to receive infrared photons and generate electrons therefrom. In another aspect, the at least one metal cone may be an array of electronically coupled metal cones.

Abstract: A system and method for determining a level of effective residual ink concentration (ERIC) in a piece of recycled paper. The piece of paper is illuminated with a beam of radiation and an amount of the beam of radiation reflected and transmitted by the piece of paper is measured. The level of ERIC is determined as a function of the reflected and transmitted radiation.

Abstract: An AFM based technique has been demonstrated for performing highly localized IR spectroscopy on a sample surface. Such a technique implemented in a commercially viable analytical instrument would be extremely useful. Various aspects of the experimental set-up have to be changed to create a commercial version. The invention addresses many of these issues thereby producing a version of the analytical technique that cab be made generally available to the scientific community.

Abstract: Methods and apparatus are disclosed for directing optical radiation to make multiple passes across an extended region of an electro-optic material, where during each pass the electro-optic material converts a portion of the optical radiation into terahertz radiation, and where the optical radiation is directed into the electro-optic material to cause an amplitude of the terahertz radiation generated from one or more earlier passes of the optical radiation to be constructively enhanced by the terahertz radiation generated from a later pass of the optical radiation.

Abstract: An apparatus for analyzing, identifying or imaging an target including a source of pulsed signals in the range of frequencies from 100 GHz to over 2 THz focused on or transmitted through the target; and a detector for acquiring spectral information from signals reflected from the target and using a multi-spectral heterodyning process to generate an electrical signal representative of some characteristics of the target. The source of pulse signals and the detector are photoconductive switches activated by a pulsed laser beam from a single mode-locked laser.

Abstract: A method of analyzing a remotely-located object includes the step of illuminating at least a portion of a targeted object with electromagnetic radiation to induce a phase transformation in the targeted object, wherein the phase transformation produces an emitter plasma, which emits terahertz radiation. The method also includes the step of ionizing a volume of an ambient gas to produce a sensor plasma by focusing an optical probe beam in the volume and the step of detecting an optical component of resultant radiation produced from an interaction of the focused optical probe beam and the terahertz radiation in the sensor plasma. Detecting an optical component of the resultant radiation emitted by the sensor plasma facilitates detection of a characteristic fingerprint of the targeted object imposed onto the terahertz radiation produced as a result of the induced phase transformation.

Abstract: Method for determining a mean radiation power P rad 0 _ of electromagnetic radiation of a radiation source, the radiation being intensity-modulated with modulation frequency ?0, in a predetermined time interval.

Abstract: A deflection device includes a tabular object for transmitting or reflecting an electromagnetic wave, a drive unit for driving the tabular object so as to rotate or perform a translation motion, and an electromagnetic wave irradiation unit for irradiating the tabular object with an electromagnetic wave so that an irradiation area extending in a direction intersecting a direction of the rotation or translation motion of the tabular object is formed.

Abstract: The present invention enables permanent biometric authentication without the risk of forgery or the like. The present invention enables living-tissue discrimination as well as biometric authentication. The roughness distribution pattern of deep-layer tissue of the skin covered with epidermal tissue is detected, thereby extracting a unique pattern of the living tissue. Then, biometric authentication is performed based upon the detected pattern. The roughness distribution pattern of the deep-layer tissue of the skin is optically detected using difference in optical properties between the epidermal tissue and the deep-layer tissue of the skin. In this case, long-wavelength light, e.g., near-infrared light is used as illumination light cast onto the skin tissue. A fork structure of a subcutaneous blood vessel is used as the portion which is to be detected, for example. The portion which is to be detected is determined based upon the structure of the fork structure.

Abstract: A mixture ratio detecting apparatus comprises: a light source which emits light including light of an infrared region; a first light detecting unit which detects the light of the infrared region from the light source; a second light detecting unit which detects light of a region having a range different from that of the first light detecting unit; and a control unit which outputs a signal pertaining to a mixture ratio based on signals from the first light detecting unit and the second light detecting unit, and controls the light source, the first light detecting unit, and the second light detecting unit.

Abstract: An apparatus for analyzing, identifying or imaging an target including a source of pulsed signals in the range of frequencies from 100 GHz to over 2 THz focused on or transmitted through the target; and a detector for acquiring spectral information from signals reflected from the target and using a multi-spectral heterodyning process to generate an electrical signal representative of some characteristics of the target. The source of pulse signals and the detector are photoconductive switches activated by a pulsed laser beam from a single mode-locked laser.

Abstract: An apparatus for analyzing, identifying or imaging an object including a source of pulsed signals in the range of frequencies from 100 GHz to over 2 THz focused on the object; and a detector for acquiring spectral information from signals reflected from the object and using a heterodyning process to generate an electrical signal representative of some characteristics of the object. The source of pulse signals and the detector is a photoconductive switch activated by a pulsed laser beam.

Abstract: Provided is a solder material test method that reduces labor and time and is preferred in operation hygiene. Detected are a first intensity at a particular wave number of infrared radiation reflected from a test-sample solder material by illuminating light to the test-sample solder material and a second intensity at the particular wave number of infrared radiation reflected from a comparative-sample solder material by illuminating light to the comparative-sample solder material. Depending upon the first and second intensities detected, intensity differences and ratios are determined. Those may be absorbance differences or intensities of between an infrared radiation absorbance to test-sample solder material and an infrared radiation absorbance to comparative-sample solder material. From the intensity difference, intensity ratio, absorbance difference and absorbance ratio, the test-sample solder material is tested for deterioration degree relatively to the comparative sample.

Abstract: The present invention generally provides a terahertz (THz) imaging system that includes a source for generating radiation (e.g., a quantum cascade laser) having one or more frequencies in a range of about 0.1 THz to about 10 THz, and a two-dimensional detector array comprising a plurality of radiation detecting elements that are capable of detecting radiation in that frequency range. An optical system directs radiation from the source to an object to be imaged. The detector array detects at least a portion of the radiation transmitted through the object (or reflected by the object) so as to form a THz image of that object.

Abstract: A portal for security screening of transport passengers includes a THz trans-receiver. In one example of the portal, the trans-receiver includes a small-spot, reflective scanning arrangement including a single detector in a heterodyne receiver configuration. In another example, the trans-receiver includes a large-beam reflective scanning arrangement with the trans-receiver in a synthetic aperture radar (SAR) configuration.

Abstract: An infrared radiation element A heat insulating layer having sufficiently smaller thermal conductivity than a semiconductor substrate, is formed on a surface in the thickness direction of the semiconductor substrate. A heating layer, which is in the form of a lamina (plane) and has larger thermal conductivity and larger electrical conductivity than the heat insulating layer, is formed on the heat insulating layer. A pair of pads 4 for energization are formed on the heating layer. The semiconductor substrate is made of a silicon substrate. The heat insulating layer and the heating layer are formed by porous silicon layers having different porosities from each other, and the heating layer has smaller porosity than the heat insulating layer. By using the infrared radiation element as an infrared radiation source of a gas sensor, it becomes possible to extend a life of the infrared radiation source.

Abstract: The present invention relates to a rain sensor that adaptively functions in a variety of different modes when deployed on vehicle windows of different thicknesses and compositions. The arrangement of multiple lens segments and reflecting surfaces in a nonsequential configuration allows utilization of a greater proportion of light rays from the at least two emitters. Further, a greater portion of the light rays emitted by the at least two emitters is captured by the lens segments and reflectors arranged about at least two detectors, and directed to the detectors. Connection to analytical circuitry then allows interpretation of electrical signals, which in turn control, for example, window wiper systems.

Abstract: An apparatus and method for analysing temperature-dependent molecular configurations such as folding comprises a multi-channel flow-through chip (12) along which molecules to be analysed pass. A temperature gradient is maintained along the length of the chip. As molecules pass along the channels they fold or unfold, in response to the changing temperature. These changing molecular configurations are investigated by simultaneously measuring the extent to which the molecules absorb UV light, and the extent to which they fluoresce. The absorption and fluorescence information is supplied to a computer system (26) for real-time analysis.

Abstract: A method for determining a location of IR-cut filter film on a substrate, the filter film and the substrate cooperatively functioning as an IR-cut filter, includes the steps of: providing an infrared laser device, an IR-cut filter and an infrared laser sensor; emitting a laser from the IR laser device to a surface of the IR-cut filter in a manner such that the laser beam is obliquely incident on an edge portion of the IR-cut filter; and determining the location of the filter film on the substrate of the IR-cut filter in such a way that, if the intensity of the laser beam received by the infrared sensor is equal to or close to zero, the location of the filter film is on a surface of the substrate facing towards the infrared laser device; if the intensity of the laser beam received by the infrared sensor is the same as or close to an intensity of the laser beam emitted from the infrared laser device, the location of the filter film is on a surface of the substrate facing away from the infrared sensor.

Abstract: Methods and apparatus for screening diverse arrays of materials using infrared imaging techniques are provided. Typically, each of the individual materials on the array will be screened or interrogated for the same material characteristic. Once screened, the individual materials may be ranked or otherwise compared relative to each other with respect to the material characteristic under investigation. According to one aspect, infrared imaging techniques are used to identify the active sites within an array of compounds by monitoring the temperature change resulting from a reaction. This same technique can also be used to quantify the stability of each new material within an array of compounds. According to another aspect, identification and characterization of condensed phase products is achieved, wherein library elements are activated by a heat source serially, or in parallel.

Abstract: A high resolution material observation system includes an object having at least one spatial dimension sufficient to support production of near-field infrared emissions, a holder adapted to receive a sample to be observed, the holder further adapted to position the sample in the near-field infrared emissions, and a thermal excitation unit, adapted to be thermally coupled to at least one of the object and the sample. The thermal excitation unit is further adapted to causing black body radiation in either the object or the sample within the infrared spectrum.

Abstract: An integrated circuit sensor may include at least one infrared sensing element on a substrate. The sensing element may include at least one first thermocouple junction heated from infrared radiation, at least one second thermocouple junction connected to the first thermocouple junction, and a controller. The controller may detect a temperature difference between the first and second thermocouple junctions, and may pump heat therebetween to drive the detected temperature difference toward a desired value. The controller may also generate an infrared radiation output signal based upon the heat pumped. The controller may alternatingly switch between detecting the temperature difference and pumping heat, and the desired temperature difference may be zero. The sensor is readily made using integrated circuit processing technology, and may, for example, be used in many types of applications, such as biometric identification by including biometric processing circuitry connected to the controller.

Abstract: Terahertz radiation generation systems and methods are implemented using a variety of methods and devices. According to an example embodiment of the present invention, method for generating terahertz radiation is implemented where the wavelength of an optical pulse is controlled, and where the wavelength is controlled as a function of the group velocity dispersion in a nonlinear crystal. The optical pulse is then directed through consecutively-inverted parallel domains in the nonlinear crystal.

Abstract: In a defect inspection apparatus which combines a plurality of probes for measuring electric properties of a specimen including a fine circuit line pattern with a charged particle beam apparatus, the charged particle beam apparatus reduces a degradation in resolution even with an image-shift of ±75 ?m or more. The defect inspection apparatus has a CAD navigation function associated with an image-shift function. The CAD navigation function uses coordinates for converting an image-shift moving amount to a DUT stage moving amount in communications between an image processing unit for processing charged particle beam images and a memory for storing information on circuit line patterns. The defect inspection provides the user with significantly improved usability.

Abstract: A method for inspecting a package to identify an object concealed in the package includes passing two beams of THz-radiation through the package. The frequency of THz radiation in one beam is different from that in the other, and the beams are at an angle to each other. Each of the transmitted beams is used to form an image of the package and the object. The absorption coefficient of the object is determined from the two images. The material of the object is determined from the absorption coefficients at the two frequencies. The method is useful for detecting explosive material concealed in baggage.

Abstract: A non-invasive active infrared device monitors amphibians and other animals in aqueous environments. An infrared emitter circuit and an infrared detector circuit are secured in a horizontal orientation with respect to each other in a u-shaped Plexiglas structure. A combination of variable resistors, a focusing lens, and a funnel allows the detector circuit to detect a pre-selected size of aquatic animal, and by extension a pre-selected species of aquatic animal. When an aquatic animal of a pre-selected size breaks the infrared beam, an event logger is triggered and records the date and time the beam is broken. This device provides a new and enormously useful system for studying the movement patterns and thus key behavioral traits of aquatic amphibians and other aquatic animals.

Abstract: The invention relates to a method for finding disconnection of a conductive wire formed on a plate glass. This method includes the steps of (a) applying a voltage to the conductive wire; and (b) imaging thermal radiation from a surface of the conductive wire by an infrared image sensor, while the step (a) is conducted, thereby producing a temperature distribution image. An apparatus for conducting the method includes (a) a power source for applying a voltage to the conductive wire; and (b) an infrared image sensor for imaging thermal radiation from a surface of the conductive wire, thereby producing a temperature distribution image.

Abstract: Concentrations of N gas species can be detected from a single beam NDIR gas sensor having a differential infrared source and an (N+1)-passband filter (having a neutral passband and N absorption passbands for N gases) mounted at a single infrared detector by driving the infrared source with N input power levels to render the source into emitting at N distinct temperatures whose radiation outputs are characterized by N corresponding Planck curves which are dependent only upon the respective source temperatures and which link a Spectral Radiant Emittance MsubLamba with wavelength, measuring N detector outputs at the single infrared detector and detecting the concentrations of N different gas species, each of the N gas species having its own unique infrared absorption passband, by (a) setting up N causality relationship equations linking outputs of the detector respectively for N different source temperatures and a set of relevant parameters of the sensor components, (b) determining the values of all of the param

Abstract: This invention relates to apparatus and methods for sensing terahertz radiation, in particular over an area, and to terahertz radiation imaging systems. A terahertz radiation sensor, the sensor comprising an optical beam input to receive an optical probe beam, a detector to modulate said probe beam responsive to terahertz radiation, and a photosensitive detector to provide an output responsive to said probe beam modulation. The sensor being configured to provide a first optical path between said optical beam input and said electro-optic detector and to provide a second optical path between said electro-optic detector and said photosensitive detector, and wherein said sensor further comprises a polarizer, said polarizer being located in both said first and said second optical paths. We further describe imaging systems for use with such a probe.