A set of electrostatic plates deflect charged particles away from the instrument and collimates the beam of incoming neutral atoms to a few degrees.
|
|
Figure 1: Schematic layout of a White-light Interferometer A CCD image sensor like those used for digital photography is placed at the point where the two images are superimposed. A broadband “white light” source is used to illuminate the test and reference surfaces. A condenser lens collimates the light from the broadband light source. A beam splitter separates the light into reference and measurement beams.
|
|
A collimator collimates the beam that is dispersed by a refracting prism and re-imaged onto a detection system by a re- imager. Special care is taken to produce the best possible image of the source onto the slit. The purpose of the collimator and re-imaging optics are to take the best possible image of the slit. An area-array of elements fills the detection system at this stage.
|
|
Diagram depicting how a spherical Fresnel lens collimates light. With the development of the steady illumination of the Argand lamp, the application of optical lenses to increase and focus the light intensity became a practical possibility. William Hutchinson developed the first practical optical system in 1763, known as a catoptric system. He constructed paraboloidal reflectors by attaching small pieces of reflective material to a cast that had been moulded into an approximate paraboloid.
|
|
Reaction kinetics in uniform supersonic flow (, CRESU ) is an experiment investigating chemical reactions taking place at very low temperatures. The technique involves the expansion of a gas or mixture of gases through a de Laval nozzle from a high pressure reservoir into a vacuum chamber. As it expands, the nozzle collimates the gas into a uniform supersonic beam that is essentially collision free and has a temperature that, in the centre of mass frame, can be significantly below that of the reservoir gas. Each nozzle produces a characteristic temperature.
|
|
TREAT has a fast-neutron hodoscope that collimates and detects fast fission neutrons emitted by the experiment fuel sample. The TREAT hodoscope consists of a front collimator, a rear collimator, a bank of detectors, electronics to interface to the detectors, and a data acquisition system. The collimator has 10 columns with 36 rows, which are aligned to an array (or arrays) of 360 detectors. The hodoscope provides time and spatial resolution of fuel motion during transients and in-place measurement of fuel distribution before, during, and after an experiment.
|
|
Diagram depicting how a spherical Fresnel lens collimates light With the development of the steady illumination of the Argand lamp, the application of optical lenses to increase and focus the light intensity became a practical possibility. William Hutchinson developed the first practical optical system in 1763, known as a catoptric system. This rudimentary system effectively collimated the emitted light into a concentrated beam, thereby greatly increasing the light's visibility. The ability to focus the light led to the first revolving lighthouse beams, where the light would appear to the mariners as a series of intermittent flashes.
|
|
Michael Robert Descour, "Non-scanning imaging spectrometry", PhD Thesis, University of Arizona (1994) The optical layout of a CTIS instrument.The optical layout of a CTIS instrument is shown at right: a field stop is placed at the image plane of an objective lens, after which a lens collimates the light before it passes through a disperser (such as a grating or prism). Finally, a re-imaging lens maps the dispersed image of the field stop onto a large-format detector array. Shown here is an example in which the device is imaging the university of Arizona's logo, uses a kinoform grating to disperse the transmitted light, and measures a dispersion pattern on the detector array.
|
|
Similarly, the structures of parabolic arches are purely in compression. Paraboloids arise in several physical situations as well. The best-known instance is the parabolic reflector, which is a mirror or similar reflective device that concentrates light or other forms of electromagnetic radiation to a common focal point, or conversely, collimates light from a point source at the focus into a parallel beam. The principle of the parabolic reflector may have been discovered in the 3rd century BC by the geometer Archimedes, who, according to a dubious legend, constructed parabolic mirrors to defend Syracuse against the Roman fleet, by concentrating the sun's rays to set fire to the decks of the Roman ships.
|
|
ShadowbandsShadow bands are thin, wavy lines of alternating light and dark that can be seen moving and undulating in parallel on plain-coloured surfaces immediately before and after a total solar eclipse.Effects During a Total Solar Eclipse They are caused by the refraction by Earth's atmospheric turbulence of the solar crescent as it thins to a narrow slit, which increasingly collimates the light reaching Earth in the minute just before and after totality. The shadows' detailed structure is due to random patterns of fine air turbulence that refract the collimated sunlight arriving from the narrow eclipse crescent. The bands' rapid sliding motion is due to shifting air currents combined with the angular motion of the sun projecting through higher altitudes.
|
|
Researchers at the Leopold-Franzens University in Innsbruck invented a dedicated PTR-MS inlet system for the analysis of aerosols and particulate matter, which they called "CHemical Analysis of aeRosol ON-line (CHARON)". After further development work in collaboration with a PTR-MS manufacturer, CHARON has become readily available as an add-on for PTR-MS instruments in 2017. The add-on consists of a honeycomb activated charcoal denuder which adsorbs organic gases but transmits particles, an aerodynamic lens system that collimates sub-µm particles, and a thermo-desorber that evaporates non-refractory organic particulate matter at moderate temperatures of 100-160°C and reduced pressures of a few mbar. So far, CHARON has predominantly being utilized within studies in the field of atmospheric chemistry, e.g.
|
|
Drawing of analyzer-based imaging Analyzer-based imaging (ABI) is also known as diffraction-enhanced imaging (DEI), phase-dispersion Introscopy and multiple- image radiography (MIR) Its setup consists of a monochromator (usually a single or double crystal that also collimates the beam) in front of the sample and an analyzer crystal positioned in Bragg geometry between the sample and the detector. (See figure to the right) This analyzer crystal acts as an angular filter for the radiation coming from the sample. When these X-rays hit the analyzer crystal the condition of Bragg diffraction is satisfied only for a very narrow range of incident angles. When the scattered or refracted X-rays have incident angles outside this range they will not be reflected at all and don´t contribute to the signal.
|
|