541 results about "Radiant intensity" patented technology

The invention consists in structuring scintillation radiation detectors as Photonic Bandgap Crystals or 3D layers of thin filaments, thus enabling extremely high spatial resolutions and achieving virtual voxellation of the radiation detector without physical separating walls. The ability to precisely measure the recoil electron track in a Compton camera enables to assess the directions of the gamma rays hitting the detector and consequently dispensing with collimators that strongly reduce the intensity of radiation detected by gamma cameras. The invention enables great enhancements of the capabilities of gamma cameras, SPECT, PET, CT and DR machines as well as their use in Homeland Security applications. Methods of fabrication of such radiation detectors are decribed.

A parallel-beam optical tomography system for imaging an object of interest includes a parallel ray beam radiation source that illuminates the object of interest with a plurality of parallel radiation beams. After passing through the object of interest the pattern of transmitted or emitted radiation intensities is magnified by a post specimen optical element or elements. An object containing tube is located within an outer tube, wherein the object of interest is held within or flows through the object containing tube. A motor may be coupled to rotate and/or translate the object containing tube to present differing views of the object of interest. One or more detector arrays are located to receive the emerging radiation from the post specimen magnifying optic. Two- or three-dimensional images may be reconstructed from the magnified parallel projection data.

The subject invention relates to a new alarm which is based on using a quarternary tunable Mid-IR laser to measure both particles and gas at the same time. The measurement is done within an area of which the gas of interest will absorb the Mid-IR radiation. By widely tuning the emission wavelength of the laser, several wavelengths can be measured in order to accurately find both gas composition and particle density with one laser based sensor. We tested a new device which use radiation between 2.27 μm and 2.316 μm. Methane gas reduces intensity of the radiation at certain wavelengths in this device, while particles/fog reduce intensity for all wavelengths. In this case, fog should not trigger an alarm, while methane leaks should. This can also be applied for CO and smoke in which one sensor will measure both parameters to sound an alarm instead of just one parameter.

A radiation source is disclosed comprising a source of charged particles that travel along a path. Target material lies along the path to generate radiation upon impact by the beam. A magnet is provided to deflect the beam prior to impacting the target. The magnet may generate a time-varying magnetic field or a constant magnetic field. A constant magnetic field may be varied spatially across the beam. The magnet may be an electromagnet or a permanent magnet. In one example, deflection of the beam results in impact of the beam on the target along a plurality of axes. In another example, portions of the beam are differentially deflected. The source may thereby irradiate an object to be scanned with more uniform radiation. The charged particles may be electrons or protons and the radiation may be X-ray or gamma ray radiation, or neutrons. Scanning systems incorporating such sources, methods of generating radiation and methods of examining objects are disclosed, as well.

A system and method for controlling the light source of a cavity ring-down spectrometer (CRDS). The system comprises a resonant optical cavity having at least two high reflectivity mirrors; a source for providing a continuous wave optical signal into the optical cavity, the source comprising an electrically pumped semiconductor gain medium; and a SOA interposed between the optical signal source and the optical cavity. The SOA receives the optical signal and transmits it to the resonant optical cavity. The system also includes a first detector for monitoring the intensity of radiation emitted from said cavity and generating a first detection signal based thereon; and at least a first controller for deactivating the optical signal based on a comparison of the first detection signal and a predetermined threshold and for thereafter reactivating the optical signal after a delay period in excess of the ring-down time of the optical cavity, the deactivating and reactivating being achieved by respectively turning off and then turning on electrical current to the SOA.

A portable survey instrument and methodology yield intensity of neutron radiation, intensity of gamma radiation, and a direction of impinging gamma radiation. The instrument uses a neutron detector surrounded by an essentially rectangular moderator with preferably four gamma ray detectors disposed symmetrically about the neutron detector and within the moderator. Material and dimensions of the moderator are selected so that the neutron-measurement is equally sensitive to fast and thermal neutrons. The moderator also induces angular responses to the gamma ray detectors. Responses of the gamma ray detectors are combined to yield a parameter indicative of the angular position of a source. The survey instrument is portable and suited for hand held use.

The present invention relates to a method for calibrating elements in a spatial light modulator (SLM) as a function of an applied element control signal. A plurality of elements are calibrated simultaneously. A beam of electromagnetic radiation is projected onto at least a part of the SLM. An image of said part of said SLM is formed on a device for measuring intensity of electromagnetic radiation. Element calibrating data is generated by using the intensity data as a function of the applied element control signal by either driving a sub-matrix comprising at least two elements out of said part of the SLM to a sequence of applied element control signals or by seeking out the control signal for each element which give the same predetermined intensity value on the device for measuring the intensity of electromagnetic radiation and stepping through N different predetermined intensity values. The invention also relates to an apparatus for patterning a workpiece having such a calibration method. Other aspects of the present invention are reflected in the detailed description.

The invention discloses a system for measuring the normal spectral emissivity of a high-temperature material, comprising a vacuum heating unit, a water cooling sleeve unit, an optical fiber sensor measurement unit and a data acquisition and analysis unit, wherein a test sample is arranged on the upper part of the vacuum heating unit, and the vacuum heating unit performs radiant heating on the lower surface of the test sample; the water cooling sleeve unit is sleeved on the upper part of the test sample, and the upper surface of the test sample is placed in a constant-temperature cold environment; the optical fiber sensor measurement unit is arranged above the test sample to measure the normal spectral radiant intensity of the upper surface of the test sample; and the data acquisition and analysis unit is connected with the optical fiber sensor measurement unit and is used for calculating the normal spectral emissivity through a multi-spectrum inversion algorithm according to the measured normal spectral radiant intensity. The invention realizes material normal spectral emissivity measurement in a spectrum range of 0.4-1.7mum and a temperature range of 600-1,500 DEG C without on-line radiometric calibration, is accurate and reliable to realize the technology, and overcomes limitations on high price, complicated structure, high difficulty in technical implementation and other applications of the conventional spectral emissivity device.

To enable differentiation between a particle and a ghost particle, a detector system resolves radiation from a ghost particle from radiation from an actual particle. The detector system outputs at least two detector signals corresponding to intensities of radiation being incident on different parts of the detector system or the detector system outputs at least two detector signals corresponding to intensities of radiation with different wavelengths being incident on the detector system. If radiation is received from a ghost particle, not each of the at least two detector signals has a level above a predetermined threshold level, whereas radiation received from a particle results in the signals having substantially a same level above a threshold level. The detector system may include a radiation detector device configured to generate the first detector signal in response to radiation incident on at least one predetermined part of the radiation detector device and a radiation blocking assembly configured to prevent radiation not originating from a particle from being incident on the predetermined part of the detector device.

A method of reducing a wave front aberration is provided for a lithographic process whereby the reducing is based on the selected pattern to be printed and the selected illumination mode used for exposure. Wave front aberrations of a projection system of a lithographic apparatus are measured and reduced by calculating adjustments of optical elements of the projection system and applying the calculated adjustments to the projection system. The calculation of adjustments is based on information on a spatial distribution of radiant intensity in a pupil of the projection system as present during exposing the radiation sensitive layer, and is limited to aberrations in projection lens pupil areas of relative high radiant flux.

An optical transmission apparatus is provided in which high optical output power is secured in an optical transmitter, the fine adjustment of the optical axis is unnecessary, and the propagation range of the optical output signal can be adaptively changed. A diffusing liquid lens includes a first liquid and a second liquid containing a scattering material that scatters light, and the curvature of the boundary surface between the first and the second liquids is changed according to the control voltage applied from a controlling unit. A first optical signal outputted from a light emitting device is diffused in the first liquid, and emitted as a second optical signal having a spread angle corresponding to the curvature of the boundary surface and a substantially uniform radiant intensity distribution.

The present invention is directed to an infrared light assembly (10, 30, 80, 90). A preferred embodiment of the light assembly (10, 30, 80, 90) may be used on aircraft or other vehicles for landing, taxi mode, or search operations. The light assembly (10, 30, 80, 90) preferably only requires about 10 to 20 watts of power. The light assembly (10, 30, 80, 90) may include a housing (12, 32, 82), a base (14, 34, 50), an IR diode (16, 36, 60), and an aspheric lens (18, 38). The base (14, 34, 50) is preferably connected to the bottom portion (22) of the housing(12, 32, 82), and the aspheric lens (18, 38) is preferably connected to the top portion (24) of the housing (12, 32, 82). The IR diode (16, 36, 60) may be mounted on the base (14, 34, 50). The housing (12, 32, 82) and the base (14, 34, 50) preferably have high thermal conductivity, and they preferably act as heat sinks. In addition, a plurality of thermal electric coolers (20, 40, 70) may be positioned between the base (14, 34, 50) and the IR diode (16, 36, 60) for additional dissipation of the heat generated by the light assembly. The IR diode (16, 36, 60) is adapted to emit infrared light. The light assembly (10, 30, 80, 90) preferably maintains a substantially constant operating temperature so that the peak emission of the IR diode (16, 36, 60) is substantially maintained. The infrared light may radiate through the hollow of the housing(12, 32, 82) to the aspheric lens (18, 38). The aspheric lens (18, 38) is preferably adapted to collimate infrared light. As a result, the light assembly (10, 30, 80, 90) may provide a collimated beam of infrared light having a NVIS radiant intensity greater than about 2.

A temperature monitoring technique for collecting radiation intensity (blackbody emission) across a broad wavelength range. A solid state spectrometer (26) acquires spectra from a sample (10) in real time and resolves the spectra to a radiation intensity (I) versus wavelength (λ) curve. This curve is fitted to Planck's equation using a non-linear least squares fitting analysis. The system can be configured to self-calibrate and then lock in an amplitude value (A) which is used in subsequent temperature measurements by fitting to the blackbody emission curve. Preferably, the spectrometer (26) is flat field corrected (36) in an initial step to counteract variations in the spectrometer response with wavelength.

The present invention provides systems, devices, device components and structures for modulating the intensity and/or energies of electrons, including a beam of incident electrons. In some embodiments, for example, the present invention provides nano-structured semiconductor membrane structures capable of generating secondary electron emission. Nano-structured semiconductor membranes of this aspect of the present invention include membranes having an array of nanopillar structures capable of providing electron emission for amplification, filtering and/or detection of incident radiation, for example secondary electron emission and/or field emission. Nano-structured semiconductor membranes of the present invention are useful as converters wherein interaction of incident primary electrons and nanopillars of the nanopillar array generates secondary emission. Nano-structured semiconductor membranes of this aspect of the present invention are also useful as directed charge amplifiers wherein secondary emission from a nanopillar array provides gain functionality for increasing the intensity of radiation comprising incident electrons.

A laser diode illuminator device and a method for optically conditioning the output beam radiated from such a device, so that highly-demanding illumination application requirements that call for high output powers within a specified field of illumination can be addressed. At the heart of the device is a two-dimensional stack of laser diode bars wherein the linear array of beamlets radiated by each laser diode bar is optically conditioned through its passage in a refractive-type micro-optics device followed by a cylindrical microlens. The micro-optics device performs collimation of the linear array of beamlets along the fast axis of the bars, and it also acts as a beam symmetrization device by interchanging the divergences of the laser beamlets along the fast and slow axes. The cylindrical microlens is for collimation of the beamlets along the slow axis. The optical conditioning is performed individually for each linear array of beamlets so that the radiance or brightness of the laser diode illuminator can be optimized while any specified field of illumination can be filled with an excellent uniformity of the radiant intensity.

The invention discloses a site target emissivity measuring system and method based on the environmental radiation change. The system comprises a target, a spectroscope and an infrared detector, wherein the target, the spectroscope and the infrared detector are sequentially arranged in the optical path direction and located on the same optical axis. The system further comprises a black body and a collecting lens. Radiation light of the black body converges on the spectroscope through the collecting lens, is reflected to the target through the spectroscope, acts on the target, then is reflected to the spectroscope and reaches the detector. The method includes the steps that firstly, radiometric calibration is conducted on the infrared detector; a system response function is established with the radiation of the black body serving as the standard; an output response value V1 of the infrared detector is measured under the condition of the environmental radiation intensity Vs1; an output response value V2 of the infrared detector is measured when the condition is changed into the environmental radiation intensity Vs2; according to the output response values measured under the two different radiation intensity conditions of the infrared detector, the reflectivity and the emissivity of the target are calculated. According to the system and method, necessary parameters are provided for infrared radiation non-contact accurate temperature measurement.

A system for and a method of controlling a spatial distribution of radiation intensity in a beam of radiation is provided. The system includes a control device located to receive the initial beam of radiation from the radiation source. The control device includes a first radiation absorbing structure located at a position in generally superposing alignment relative a position of a second radiation absorbing structure. Each first and second radiation absorbing structure is operable to independently articulate. The modulator configuration signal is operable to cause adjustment of the position of at least one of the first and second radiation absorbing structures relative to the other so as to selectively adjust a spatial distribution of radiation intensity of a modulated beam.