Its rainbow-like features are produced by water droplets that diffract incoming sunlight.
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Many comb jellies produce a pulsing rainbow effect as their beating cilia diffract light.
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But a surface can also diffract light, bending its path—when light grazes past an object.
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These scales refract light, splitting it into its component wavelengths, and also diffract it, causing those various wavelengths to interfere with one another.
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Dr Menon and his team thought mimicking the way morphos refract and diffract light might thus let them create more realistic and usable holograms than today's.
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They diffract the light from the stage and turn every flash into a cheap, spotty rainbow, a dozen needless spectrums clumsily holding firm over the image of the stage.
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If you barely let a point of sunlight sneak through, you can diffract and project the light using a fleshly pinhole camera: There are other, more effective ways to use projection to your advantage, though.
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Current optics technologies being used by HoloLens, Vuzix and Magic Leap all rely on a complicated high-end type of waveguide display technology that utilizes lenses with etched structures that capture and diffract light being projected into the edge of the glass.
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A liquid, whose atoms are jumbled and moving, will scatter the X-rays all over the place and fail to create a pattern, whereas a crystal's rigid lattice of atoms—such as in salt or diamond—will diffract them in a more orderly manner due to their repetitive internal structure.
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Relatively larger molecules like buckyballs were also shown to diffract.
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By 1927, Davisson and Germer and separately G. Thomson successfully diffract electrons, providing experimental evidence of wave- particle duality.
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Because of their highly ordered and repetitive atomic structure (Bravais lattice), crystals diffract x-rays in a coherent manner, also referred to as Bragg's reflection.
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The Kapitsa–Dirac effect causes beams of particles to diffract as the result of meeting a standing wave of light. Light can be used to position matter using various phenomena (see optical tweezers).
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Emerging methods like multiple isomorphous replacement use the presence of a heavy metal ion to diffract the x-rays into a more predictable manner, reducing the number of variables involved and resolving the phase problem.
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Usually two lasers at an angle are used to build an EIG. The EIG is used to diffract a third laser, to monitor the behavior of the underlying substrate where the EIG was written or to serve as a switch for one of the lasers involved in the process.
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Diffraction phenomena by small obstacles are also important at high frequencies. Signals for urban cellular telephony tend to be dominated by ground-plane effects as they travel over the rooftops of the urban environment. They then diffract over roof edges into the street, where multipath propagation, absorption and diffraction phenomena dominate.
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Membrane optics employ plastic in place of glass to diffract rather than refract or reflect light. Concentric microscopic grooves etched into the plastic provide the diffraction. Glass transmits light with 90% efficiency, while membrane efficiencies range from 30-55%. Membrane thickness is on the order of that of plastic wrap.
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U.S. Space Shuttle or Russian Space Station, Mir. Protein crystallization is the process of formation of a regular array of individual protein molecules stabilized by crystal contacts. If the crystal is sufficiently ordered, it will diffract. Some proteins naturally form crystalline arrays, like aquaporin in the lens of the eye.
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Volume holograms were first treated by H. Kogelnik in 1969 by the so-called "coupled-wave theory". For volume phase holograms it is possible to diffract 100% of the incoming reference light into the signal wave, i.e., full diffraction of light can be achieved. Volume absorption holograms show much lower efficiencies.
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A cross section of an ideal Airy beam would reveal an area of principal intensity, with a series of adjacent, less luminous areas trailing off to infinity. In reality, the beam is truncated so as to have a finite composition. As the beam propagates, it does not diffract, i.e., does not spread out.
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Other birds with breast muscle more suitable for sustained flight, such as ducks and geese, have red muscle (and therefore dark meat) throughout. Some cuts of meat including poultry expose the microscopic regular structure of intracellular muscle fibrils which can diffract light and produce iridescent colors, an optical phenomenon sometimes called structural coloration.
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If the slit width is large, light passing the slit does not diffract so much, but the wider slits create crosstalk due to geometric ray paths. Therefore, the design suffers more crosstalk. The brightness of the display is increased. Therefore, the best slit width is given by a trade off between crosstalk and brightness.
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Membrane optics is a flat lens that employs plastic in place of glass to diffract rather than reflect or refract light. Concentric microscopic grooves etched into the plastic provide the diffraction. Glass transmits light with 90% efficiency, while membrane efficiencies range from 30-55%. Membrane thickness is on the order of that of plastic wrap.
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On the downside, higher frequencies are less susceptible to diffraction. This means that the signals will not bend around obstructions as readily as a VHF signal. This is a particular problem for receivers located in depressions and valleys. Normally the upper edge of the landform acts as a knife-edge and causes the signal to diffract downwards.
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Leia Inc. is a Menlo Park-based startup company developing display technology that uses nanostructures to diffract a backlight directionally into a light field and create "holographic" visual effects. Leia is headquartered in Menlo Park, California, with a nano-fabrication center in Palo Alto, a content team in Los Angeles and industrialization center in Suzhou, China.
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A second type of OTH radar uses much lower frequencies, in the longwave bands. Radio waves at these frequencies can diffract around obstacles and follow the curving contour of the earth, traveling beyond the horizon. Echos reflected off the target return to the transmitter location by the same path. These ground waves have the longest range over the sea.
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Hydrogen–deuterium exchange of fast-exchanging species (e.g. hydroxyl groups) can be measured at atomic resolution quantitatively by neutron crystallography, and in real time if exchange is conducted during the diffraction experiment. High intensity neutron beams are generally generated by spallation at linac particle accelerators such as the Spallation Neutron Source. Neutrons diffract crystals similarly to X-rays and can be used for structural determination.
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Under certain beam geometries, the anti-Stokes emission may diffract away from the probe beam, and can be detected in a separate direction. While intuitive, this classical picture does not take into account the quantum mechanical energy levels of the molecule. Quantum mechanically, the CARS process can be understood as follows. Our molecule is initially in the ground state, the lowest energy state of the molecule.
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The spatial coherence guarantees a uniform wavefront prior to beam splitting. Second, it is preferred to use a monochromatic or temporally coherent light source. This is readily achieved with a laser but broadband sources would require a filter. The monochromatic requirement can be lifted if a diffraction grating is used as a beam splitter, since different wavelengths would diffract into different angles but eventually recombine anyway.
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A special kind of monochromator is needed to diffract the radiation produced in X-Ray-Sources. This is because X-rays have a refractive index n ≈ 1. Bragg came up with the equation that describes x-ray/neutron diffraction when those particles pass a crystal lattice.(X-ray diffraction) For this purpose "perfect crystals" have been produced in many shapes, depending on the geometry and energy range of the instrument.
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ULVZs are discovered by the delay and scattering of body waves that reflect and diffract on or are refracted by the core-mantle boundary. Different body waves types give different constraints on the dimensions or velocity contrasts of the ULVZ. Even though ULVZs are discovered in places, it remains difficult to map out their extent and constrain their density and velocity. Usually trade-offs between various parameters exist.
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Based on analysis by French physicist Augustin-Jean Fresnel, they are sometimes called Fresnel zone plates in his honor. The zone plate's focusing ability is an extension of the Arago spot phenomenon caused by diffraction from an opaque disc. A zone plate consists of a set of concentric rings, known as Fresnel zones, which alternate between being opaque and transparent. Light hitting the zone plate will diffract around the opaque zones.
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They use diffraction instead of refraction or reflection to focus the light. Light hitting the FZP will diffract around the opaque zones, therefore an image will be created when constructive interference occurs. The opaque and transparent zones can be spaced so that imaging occurs at different focuses. In the early work on coded-apertures, pinholes were randomly distributed on the mask and placed in front of a source to be analyzed.
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These diffracted electrons can escape the material and some will collide and excite the phosphor causing it to fluoresce. Inside the SEM, the electron beam is focussed onto the surface of a crystalline sample. The electrons enter the sample and some may backscatter. Escaping electrons may exit near to the Bragg angle and diffract to form Kikuchi bands which correspond to each of the lattice diffracting crystal planes.
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Radio waves at MF wavelengths propagate via ground waves and reflection from the ionosphere (called skywaves). Ground waves follow the contour of the Earth. At these wavelengths they can bend (diffract) over hills, and travel beyond the visual horizon, although they may be blocked by mountain ranges. Typical MF radio stations can cover a radius of several hundred miles from the transmitter, with longer distances over water and damp earth.
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Hydrogen atoms, with between one and zero electrons in a biological setting, diffract X-rays poorly and are effectively invisible under normal experimental conditions. Neutrons scatter from atomic nuclei, and are therefore capable of detecting hydrogen and deuterium atoms. Hydrogen atoms are routinely replaced with deuterium, which introduce a strong and positive scattering factor. It is often sufficient to replace only the solvent and labile hydrogen atoms in a protein crystal by vapor diffusion.
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Knife-edge diffraction is the propagation mode where radio waves are bent around sharp edges. For example, this mode is used to send radio signals over a mountain range when a line-of-sight path is not available. However, the angle cannot be too sharp or the signal will not diffract. The diffraction mode requires increased signal strength, so higher power or better antennas will be needed than for an equivalent line-of-sight path.
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This expression comes from word "lomcovat" which means to jiggle; shake violently (violently move with short moves with something, what is attached hardly - e.g. the jail grille). The etymology origin is in Lomit which means "to diffract; to divide; braking (rod)," most likely a reference to the stick manipulation during the maneuvre. In the 1940s Czech aerobatic pilots called this a Talířek which means a small saucer, after the horizontal rotary movement of the aircraft.
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VHF signals will be seen by antennas in the valley, whereas UHF bends about as much, and far less signal will be received. The same effect also makes UHF signals more difficult to receive around obstructions. VHF will quickly diffract around trees and poles and the received energy immediately downstream will be about 40% of the original signal. In comparison, UHF blockage by the same obstruction will result on the order of 10% being received.
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A dielectric, laser output-coupler that is 75–80% reflective between 500 and 600 nm, on a 3° wedge prism made of quartz glass. Left: The mirror is highly reflective to yellow and green but highly transmissive to red and blue. Right: The mirror transmits 25% of the 589 nm laser light. Because the smoke particles diffract more light than they reflect, the beam appears much brighter when reflecting back toward the observer.
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One fascinating field in which SMPs are impacting quite significantly nowadays is photonics. Due to the shape changing capability, SMPs enable the production of functional and responsive photonic gratings. In fact, by using modern soft lithography techniques such as replica molding, it is possible to imprint periodic nanostructures, with sizes of the order of magnitude of visible light, onto the surface of shape memory polymeric blocks. As a result of the refractive index periodicity, these systems diffract light.
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Diffraction depends on the relationship between the wavelength and the size of the obstacle. In other words, the size of the obstacle in wavelengths. Lower frequencies diffract around large smooth obstacles such as hills more easily. For example, in many cases where VHF (or higher frequency) communication is not possible due to shadowing by a hill, it is still possible to communicate using the upper part of the HF band where the surface wave is of little use.
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Because gas molecules diffract electrons and affect the quality of the electron gun, RHEED experiments are performed under vacuum. The RHEED system must operate at a pressure low enough to prevent significant scattering of the electron beams by gas molecules in the chamber. At electron energies of 10keV, a chamber pressure of 10−5 mbar or lower is necessary to prevent significant scattering of electrons by the background gas. In practice, RHEED systems are operated under ultra high vacuums.
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The Hydrogen One's design is influenced by the lens mounts of Red's cinema cameras, with aluminum and Kevlar materials. scalloped grips, and texturing; hardware buttons and a fingerprint reader are integrated into some of the scallops. It features a 5.7-inch 1440p LCD with 3D display technology branded as "4V" ("4 View"). Developed by the Red-backed startup Leia, it uses nanostructures to diffract the display's backlight into a light field, creating a "holographic" depth effect.
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Atmospheric radio noise increases with decreasing frequency. At the LF band and below, it is far above the thermal noise floor in receiver circuits. Therefore, inefficient antennas much smaller than the wavelength are adequate for reception Because of their long wavelength, low frequency radio waves can diffract over obstacles like mountain ranges and travel beyond the horizon, following the contour of the Earth. This mode of propagation, called ground wave, is the main mode in the LF band.
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This ability to interfere and diffract is related to coherence (classical or quantum) of the waves produced at both slits. The association of an electron with a wave is unique to quantum theory. When the incident beam is represented by a quantum pure state, the split beams downstream of the two slits are represented as a superposition of the pure states representing each split beam. The quantum description of imperfectly coherent paths is called a mixed state.
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Because of their long wavelength, radio waves in this frequency range can diffract over obstacles like mountain ranges and travel beyond the horizon, following the contour of the Earth. This mode of propagation, called ground wave, is the main mode in the longwave band. The attenuation of signal strength with distance by absorption in the ground is lower than at higher frequencies, and falls with frequency. Low frequency ground waves can be received up to from the transmitting antenna.
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') In his 1704 book Opticks, Isaac Newton described the mechanism of the colours other than the brown pigment of peacock tail feathers. Newton noted that In 1892, Frank Evers Beddard noted that Chrysospalax golden moles' thick fur was structurally coloured. Thomas Young (1773–1829) extended Newton's particle theory of light by showing that light could also behave as a wave. He showed in 1803 that light could diffract from sharp edges or slits, creating interference patterns.
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These are usually observed much closer to the light source than halos, and are caused by very fine particles, like water droplets, ice crystals, or smoke particles in a hazy sky. When the particles are all nearly the same size they diffract the incoming light at very specific angles. The exact angle depends on the size of the particles. Diffraction coronas are commonly observed around light sources, like candle flames or street lights, in the fog.
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Radio waves are very widely used in modern technology for fixed and mobile radio communication, broadcasting, radar and radio navigation systems, communications satellites, wireless computer networks and many other applications. Different frequencies of radio waves have different propagation characteristics in the Earth's atmosphere; long waves can diffract around obstacles like mountains and follow the contour of the earth (ground waves), shorter waves can reflect off the ionosphere and return to earth beyond the horizon (skywaves), while much shorter wavelengths bend or diffract very little and travel on a line of sight, so their propagation distances are limited to the visual horizon. To prevent interference between different users, the artificial generation and use of radio waves is strictly regulated by law, coordinated by an international body called the International Telecommunications Union (ITU), which defines radio waves as "electromagnetic waves of frequencies arbitrarily lower than 3 000 GHz, propagated in space without artificial guide". The radio spectrum is divided into a number of radio bands on the basis of frequency, allocated to different uses.
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In the RHEED setup, only atoms at the sample surface contribute to the RHEED pattern. The glancing angle of incident electrons allows them to escape the bulk of the sample and to reach the detector. Atoms at the sample surface diffract (scatter) the incident electrons due to the wavelike properties of electrons. The diffracted electrons interfere constructively at specific angles according to the crystal structure and spacing of the atoms at the sample surface and the wavelength of the incident electrons.
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Models are refined until their predicted patterns match to as great a degree as can be achieved without radical revision of the model. This is a painstaking process, made much easier today by computers. The mathematical methods for the analysis of diffraction data only apply to patterns, which in turn result only when waves diffract from orderly arrays. Hence crystallography applies for the most part only to crystals, or to molecules which can be coaxed to crystallize for the sake of measurement.
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With the use of copper nanoparticles, the sensor does not require any enzyme and therefore has no need to deal with enzyme degradation and denaturation. As described in Figure 3, depending on the level of glucose, the nanoparticles in the sensor diffract the incident light at a different angle. Consequently, the resulting diffracted light gives a different color based on the level of glucose. In fact, the nanoparticles enable the sensor to be more stable at high temperatures and varying pH, and more resistant to toxic chemicals.
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"Restricted QCC" refers to the first two moments of the probability distribution and is true even when the wave packets diffract, while "detailed QCC" requires smooth potentials which vary over scales much larger than the wavelength, which is what Bohr considered. The post-1925 new quantum theory came in two different formulations. In matrix mechanics, the correspondence principle was built in and was used to construct the theory. In the Schrödinger approach classical behavior is not clear because the waves spread out as they move.
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Because of the way Minovsky particles react with other types of radiation, radar systems and long-range wireless communication systems become useless, infra-red signals are defracted and their accuracy decreases, and visible light is fogged. This became known as the "Minovsky Effect". The disruption of electromagnetic radiation is due to the small lattice of the I-field creating fringes that long wavelengths cannot penetrate, and that diffract wavelengths that have similar distance with the fringes. This diffraction and polarization process disrupts the electromagnetic waves.
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Soft X-rays have different optical properties than visible light and therefore experiments must take place in ultra high vacuum, where the photon beam is manipulated using special mirrors and diffraction gratings. Gratings diffract each energy or wavelength present in the incoming radiation in a different direction. Grating monochromators allow the user to select the specific photon energy they wish to use to excite the sample. Diffraction gratings are also used in the spectrometer to analyze the photon energy of the radiation emitted by the sample.
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Light+Time The Light + Time Tower is a sculpture located in the city of Raleigh, North Carolina designed to diffract the morning and afternoon sunlight into vibrant colors visible to the commuters who pass by it. It is located in the median of Capital Boulevard just northeast of the Fairview Road overpass. The Light + Time Tower consists of a tower supporting 20 panels of clear glass. It was created by internationally known sculptor Dale Eldred and was commissioned by the Raleigh Arts Commission in 1995.
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Another type of solid-state tunable filter is the acousto optic tunable filter (AOTF), based on the principles of the acousto- optic modulator. Compared with LCTFs, AOTFs enjoy a much faster tuning speed (microseconds versus milliseconds) and broader wavelength ranges. However, since they rely on the acousto-optic effect of sound waves to diffract and shift the frequency of light, imaging quality is comparatively poor, and the optical design requirements are more stringent. Indeed, LCTFs are capable of diffraction-limited imaging onto high-resolution imaging sensors.
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Precious opal displays play-of-color (iridescence), common opal does not. Play-of-color is defined as "a pseudo chromatic optical effect resulting in flashes of colored light from certain minerals, as they are turned in white light." The internal structure of precious opal causes it to diffract light, resulting in play-of-color. Depending on the conditions in which it formed, opal may be transparent, translucent, or opaque and the background color may be white, black, or nearly any color of the visual spectrum.
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A true quantum-mechanical wave would diffract from the inner hemisphere, leaving a diffraction pattern to be observed on the outer hemisphere. This is not really an objection, but rather an affirmation that a partial collapse of the wave function has occurred. If a diffraction pattern were not observed, one would be forced to conclude that the particle had collapsed down to a ray, and stayed that way, as it passed the inner hemisphere; this is clearly at odds with standard quantum mechanics. Diffraction from the inner hemisphere is expected.
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Artificial dielectrics are fabricated composite materials, often consisting of arrays of conductive shapes or particles in a nonconductive support matrix, designed to have specific electromagnetic properties similar to dielectrics. As long as the lattice spacing is smaller than a wavelength, these substances can refract and diffract electromagnetic waves, and are used to make lenses, diffraction gratings, mirrors, and polarizers for microwaves. These were first conceptualized, constructed and deployed for interaction in the microwave frequency range in the 1940s and 1950s. The constructed medium, the artificial dielectric, has an effective permittivity and effective permeability, as intended.
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The energy width of the non- monochromated X-ray is roughly 0.70 eV, which, in effect is the ultimate energy resolution of a system using non-monochromatic X-rays. Non- monochromatic X-ray sources do not use any crystals to diffract the X-rays which allows all primary X-rays lines and the full range of high-energy Bremsstrahlung X-rays (1–12 keV) to reach the surface. The ultimate energy resolution (FWHM) when using a non-monochromatic Mg Kα source is 0.9–1.0 eV, which includes some contribution from spectrometer-induced broadening.
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Double- slit fringes with sodium light illumination In the double-slit experiment, the two slits are illuminated by a single light beam. If the width of the slits is small enough (less than the wavelength of the light), the slits diffract the light into cylindrical waves. These two cylindrical wavefronts are superimposed, and the amplitude, and therefore the intensity, at any point in the combined wavefronts depends on both the magnitude and the phase of the two wavefronts.Born & Wolf, 1999, Figure 7.4 These fringes are often known as Young's fringes.
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Although this is quite a lot of information, this data has to be combined with absorption measurements of the so-called "pre-edge" region. Those measurements are called XANES (X-ray absorption near edge structure). Fig.4: XAS Measurement against HERFD In synchrotron facilities those measurement can be done at the same time, yet the experiment setup is quite complex and needs exact and fine tuned crystal monochromators to diffract the tangential beam coming from the electron storage ring. Method is called HERFD, which stands for High Energy Resolution Fluorescence Detection.
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With computer-controlled etching, the technology to create thin plastic sheets with thousands of microscopic ‘prism’ lenses that can magnify or diffract light can be made. Since violet light has more energy than red, and bends more when refracted, some lenses can distort an image if they don’t focus all of the colors at the same point. This distortion is called chromatic aberration. One type of film etching creates lenses that deliberately exaggerate this aberration, separating the colors of an image into different convergence points in the visual field. It’s a patented process called ChromaDepth.
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Early in 1951 Franklin finally arrived. Wilkins was away on holiday and missed an initial meeting at which Raymond Gosling stood in for him along with Alex Stokes, who, like Crick, would solve the basic mathematics that make possible a general theory of how helical structures diffract X-rays. No work had been done on DNA in the laboratory for several months; the new X-ray tube sat unused, waiting for Franklin. Franklin ended up with the DNA from Signer, Gosling became her PhD student, and she had the expectation that DNA X-ray diffraction work was her project.
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The rise of the noise at low frequencies (left side) is radio noise caused by slow processes in the Earth's magnetosphere. Due to their extremely long wavelength, ELF waves can diffract around large obstacles, are not blocked by mountain ranges or the horizon, and can travel around the curve of the Earth. ELF and VLF waves propagate long distances by an Earth-ionosphere waveguide mechanism. The Earth is surrounded by a layer of charged particles (ions and electrons) in the atmosphere at an altitude of about at the bottom of the ionosphere, called the D layer which reflects ELF waves.
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Lower frequencies, with longer wavelengths, diffract the sound around the head forcing the brain to focus only on the phasing cues from the source. Helmut Haas discovered that we can discern the sound source despite additional reflections at 10 decibels louder than the original wave front, using the earliest arriving wave front. This principle is known as the Haas effect, a specific version of the precedence effect. Haas measured down to even a 1 millisecond difference in timing between the original sound and reflected sound increased the spaciousness, allowing the brain to discern the true location of the original sound.
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An acousto-optic modulator consists of a piezoelectric transducer which creates sound waves in a material like glass or quartz. A light beam is diffracted into several orders. By vibrating the material with a pure sinusoid and tilting the AOM so the light is reflected from the flat sound waves into the first diffraction order, up to 90% deflection efficiency can be achieved. An acousto-optic modulator (AOM), also called a Bragg cell or an acousto-optic deflector (AOD), uses the acousto-optic effect to diffract and shift the frequency of light using sound waves (usually at radio-frequency).
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In the field of transmission electron microscopy, phase-contrast imaging may be employed to image columns of individual atoms. This ability arises from the fact that the atoms in a material diffract electrons as the electrons pass through them (the relative phases of the electrons change upon transmission through the sample), causing diffraction contrast in addition to the already present contrast in the transmitted beam. Phase-contrast imaging is the highest resolution imaging technique ever developed, and can allow for resolutions of less than one angstrom (less than 0.1 nanometres). It thus enables the direct viewing of columns of atoms in a crystalline material.
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Because the fault affected by the earthquake was in a nearly north–south orientation, the greatest strength of the tsunami waves was in an east–west direction. Bangladesh, which lies at the northern end of the Bay of Bengal, had few casualties despite being a low- lying country relatively near the epicentre. It also benefited from the fact that the earthquake proceeded more slowly in the northern rupture zone, greatly reducing the energy of the water displacements in that region. Average height of the waves Coasts that have a landmass between them and the tsunami's location of origin are usually safe; however, tsunami waves can sometimes diffract around such landmasses.
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John Sinko and Clifford Schlecht researched a form of reversed-thrust laser propulsion as a macroscopic laser tractor beam. Intended applications include remotely manipulating space objects at distances up to about 100 km, removal of space debris, and retrieval of adrift astronauts or tools on-orbit. In March 2011, Chinese scientists posited that a specific type of Bessel beam (a special kind of laser that does not diffract at the centre) is capable of creating a pull- like effect on a given microscopic particle, forcing it towards the beam source. The underlining physics is the maximization of forward scattering via interference of the radiation multipoles.
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A RHEED system requires an electron source (gun), photoluminescent detector screen and a sample with a clean surface, although modern RHEED systems have additional parts to optimize the technique. The electron gun generates a beam of electrons which strike the sample at a very small angle relative to the sample surface. Incident electrons diffract from atoms at the surface of the sample, and a small fraction of the diffracted electrons interfere constructively at specific angles and form regular patterns on the detector. The electrons interfere according to the position of atoms on the sample surface, so the diffraction pattern at the detector is a function of the sample surface.
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Steps of 321x321px X-ray crystallography is one of the more efficient and important methods for attempting to decipher the three dimensional configuration of a folded protein. To be able to conduct X-ray crystallography, the protein under investigation must be located inside a crystal lattice. To place a protein inside a crystal lattice, one must have a suitable solvent for crystallization, obtain a pure protein at supersaturated levels in solution, and precipitate the crystals in solution. Once a protein is crystallized, x-ray beams can be concentrated through the crystal lattice which would diffract the beams or shoot them outwards in various directions.
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He created a towering sculpture in a Kansas City park that sprayed water in order to create prismatic light refractions. His emphasis increasingly focused on light; he used mirrors, pure pigments, gas flames, fluorescent paint, refraction tape, glass, neon tubes and other materials to create light effects. "I want the sculptures to remind us all," he said, "that our lives are inextricably linked to light, and that our universe is in constant motion." He created the Light+Time Tower at the city of Raleigh, North Carolina designed to diffract the morning and afternoon sunlight into vibrant colors visible to the commuters who pass by it.
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If the oil content is less than 15 ppm, the OCM allows the water to be discharged overboard. If the oil content is higher than 15 ppm, the OCM will activate an alarm and move a three-way valve that, within a short period of time, will recirculate the overboard discharge water to a tank on the OWS suction side. An OCM takes a trickle sample from the OWS overboard discharge line and shines a light through the sample to an optical sensor. Since small oil droplets will diffract and diffuse light, a change in signal at the sensor will indicate the presence of oil.
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With Wi-Fi signals line-of-sight usually works best, but signals can transmit, absorb, reflect, refract, diffract and fading through and around structures, both man-made and natural. Due to the complex nature of radio propagation at typical Wi-Fi frequencies, particularly around trees and buildings, algorithms can only approximately predict Wi-Fi signal strength for any given area in relation to a transmitter. This effect does not apply equally to long-range Wi-Fi, since longer links typically operate from towers that transmit above the surrounding foliage. Mobile use of Wi-Fi over wider ranges is limited, for instance, to uses such as in an automobile moving from one hotspot to another.
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This means that as it propagates, it does not diffract and spread out; this is in contrast to the usual behavior of light (or sound), which spreads out after being focused down to a small spot. Bessel beams are also self-healing, meaning that the beam can be partially obstructed at one point, but will re-form at a point further down the beam axis. As with a plane wave, a true Bessel beam cannot be created, as it is unbounded and would require an infinite amount of energy. Reasonably good approximations can be made, however, and these are important in many optical applications because they exhibit little or no diffraction over a limited distance.
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This deflection can be as big as one-quarter wavelength hence creating diffraction effects on incident light that is reflected at an angle that is different from that of the incident light. The wavelength to diffract is determined by the spatial frequency of the ribbons. As this spatial frequency is determined by the photolithographic mask used to form the GLV device in the CMOS fabrication process, the departure angles can be very accurately controlled, which is useful for optical switching applications. Switching from undeflected to maximum ribbon deflection can occur in 20 nanoseconds, which is a million times faster than conventional LCD display devices, and about 1000 times faster than TI’s DMD technology.
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The transmitter antenna only needs to be 10 to 20 cm long, and receiver power usage is much lower; batteries can therefore last longer. In addition, no crystals or frequency selection is required as the latter is performed automatically by the transmitter. However, the short wavelengths do not diffract as easily as the longer wavelengths of PCM/PPM, so 'line of sight' is required between the transmitting antenna and the receiver. Also, should the receiver lose power, even for a few milliseconds, or get 'swamped' by 2.4 GHz interference, it can take a few seconds for the receiver - which, in the case of 2.4 GHz, is almost invariably a digital device - to re-sync.
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This is due to the addition, or interference, of different points on the wavefront (or, equivalently, each wavelet) that travel by paths of different lengths to the registering surface. However, if there are multiple, closely spaced openings, a complex pattern of varying intensity can result. These effects also occur when a light wave travels through a medium with a varying refractive index, or when a sound wave travels through a medium with varying acoustic impedance – all waves diffract, including gravitational waves, water waves, and other electromagnetic waves such as X-rays and radio waves. Furthermore, quantum mechanics also demonstrates that matter possesses wave-like properties, and hence, undergoes diffraction (which is measurable at subatomic to molecular levels).
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The efficiency of a grating may also depend on the polarization of the incident light. Gratings are usually designated by their groove density, the number of grooves per unit length, usually expressed in grooves per millimeter (g/mm), also equal to the inverse of the groove period. The groove period must be on the order of the wavelength of interest; the spectral range covered by a grating is dependent on groove spacing and is the same for ruled and holographic gratings with the same grating constant. The maximum wavelength that a grating can diffract is equal to twice the grating period, in which case the incident and diffracted light are at ninety degrees to the grating normal.
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Densely built Manhattan has been shown to approach a Rayleigh-fading environment. One second of Rayleigh fading with a maximum Doppler shift of 10 Hz. One second of Rayleigh fading with a maximum Doppler shift of 100 Hz. The requirement that there be many scatterers present means that Rayleigh fading can be a useful model in heavily built-up city centres where there is no line of sight between the transmitter and receiver and many buildings and other objects attenuate, reflect, refract, and diffract the signal. Experimental work in Manhattan has found near-Rayleigh fading there. In tropospheric and ionospheric signal propagation the many particles in the atmospheric layers act as scatterers and this kind of environment may also approximate Rayleigh fading.
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For an EBSD measurement a flat/polished crystalline specimen is placed in the SEM chamber at a highly tilted angle (~70° from horizontal) towards the diffraction camera, to increase the contrast in the resultant electron backscatter diffraction pattern. The phosphor screen is located within the specimen chamber of the SEM at an angle of approximately 90° to the pole piece and is coupled to a compact lens which focuses the image from the phosphor screen onto the CCD camera. In this configuration, some of the electrons which enter the sample backscatter and may escape. As these electrons leave the sample, they may exit at the Bragg condition related to the spacing of the periodic atomic lattice planes of the crystalline structure and diffract.
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As computing power has grown exponentially this approach to research, often referred to as in silico (as opposed to in vitro and in vivio), has amassed more attention especially in the area of bioinformatics. More specifically, within bioinformatics, is the study of proteins or proteomics, which is the elucidation of their unknown structures and folding patterns. The general approach in the elucidation of protein structure has been to first purify a protein, crystallize it and then send X-rays through such a purified protein crystal to observe how these x-rays diffract into specific pattern—a process referred to as X-ray crystallography. However, many proteins, especially those embedded in cellular membranes, are nearly impossible to crystallize due to their hydrophobic nature.
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Because of their large wavelengths, VLF radio waves can diffract around large obstacles and so are not blocked by mountain ranges or the horizon, and can propagate as ground waves following the curvature of the Earth. Ground waves are less important beyond several hundred to a thousand miles, and the main mode of long distance propagation is an Earth-ionosphere waveguide mechanism. The Earth is surrounded by a conductive layer of electrons and ions in the upper atmosphere at the bottom of the ionosphere called the D layer at 60 to 90 km (37 to 56 miles) altitude, which reflects VLF radio waves. The conductive ionosphere and the conductive Earth form a horizontal "duct" a few VLF wavelengths high, which acts as a waveguide confining the waves so they don't escape into space.
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A powder x-ray diffractometer in motion X-ray crystallography (XRC) is the experimental science determining the atomic and molecular structure of a crystal, in which the crystalline structure causes a beam of incident X-rays to diffract into many specific directions. By measuring the angles and intensities of these diffracted beams, a crystallographer can produce a three- dimensional picture of the density of electrons within the crystal. From this electron density, the mean positions of the atoms in the crystal can be determined, as well as their chemical bonds, their crystallographic disorder, and various other information. Since many materials can form crystals—such as salts, metals, minerals, semiconductors, as well as various inorganic, organic, and biological molecules—X-ray crystallography has been fundamental in the development of many scientific fields.
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On the other hand, spatial solitons are unstable, so any small perturbation (due to noise, for example) can cause the soliton to diffract as a field in a linear medium or to collapse, thus damaging the material. It is possible to create stable spatial solitons using saturating nonlinear media, where the Kerr relationship n(I) = n + n_2 I is valid until it reaches a maximum value. Working close to this saturation level makes it possible to create a stable soliton in a three-dimensional space. If we consider the propagation of shorter (temporal) light pulses or over a longer distance, we need to consider higher-order corrections and therefore the pulse carrier envelope is governed by the higher-order nonlinear Schrödinger equation (HONSE) for which there are some specialized (analytical) soliton solutions.
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The apparatus used in the colour vision experiments is depicted in Fig. 1. It was constructed by joining a box of (AK) with a box of (KN) at a 100-degree angle. A mirror at M reflects light coming through the opening at BC towards a lens at L. Two equilateral prisms at P diffract light coming from the three slits at X, Y, and Z. This illuminated the prisms with the combination of the spectral colors created by the diffraction of the light from the slits. This light was also visible through the lens at L. The observer then peered through the slit at E while the operator adjusted the position and width of each slit at X, Y, and Z until the observer could not distinguish the prism light from the pure white light reflected by the mirror.
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The boundaries between far infrared, terahertz radiation, microwaves, and ultra-high-frequency radio waves are fairly arbitrary and are used variously between different fields of study. Microwaves travel by line-of-sight; unlike lower frequency radio waves they do not diffract around hills, follow the earth's surface as ground waves, or reflect from the ionosphere, so terrestrial microwave communication links are limited by the visual horizon to about . At the high end of the band they are absorbed by gases in the atmosphere, limiting practical communication distances to around a kilometer. Microwaves are widely used in modern technology, for example in point-to-point communication links, wireless networks, microwave radio relay networks, radar, satellite and spacecraft communication, medical diathermy and cancer treatment, remote sensing, radio astronomy, particle accelerators, spectroscopy, industrial heating, collision avoidance systems, garage door openers and keyless entry systems, and for cooking food in microwave ovens.
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The composition of X-rays was unknown, his father argued that X-rays are streams of particles, others argued that they are waves. Max von Laue directed an X-ray beam at a crystal in front of a photographic plate; alongside of the spot where the beam struck there were additional spots from deflected rays – hence X-rays are waves. In 1912, as a first-year research student at Cambridge, W. L. Bragg, while strolling by the river, had the insight that crystals made from parallel sheets of atoms would not diffract X-ray beams that struck their surface at most angles because X-rays deflected by collisions with atoms would be out of phase, cancelling one another out. However, when the X-ray beam stuck at an angle at which the distances it passed between atomic sheets in the crystal equalled the X-ray's wavelength then those deflected would be in phase and produce a spot on a nearby film.
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