Both packs of Trojans consist of predominantly of dark, reddish rocks with a matte, non-reflecting surface.
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A radio telescope's bowl-shaped reflecting surface — that giant glinting dish — is tiled with metal panels, each one polished to exacting specifications.
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The issue of the photoswitch that the reflecting efficiency of the reflecting member may be drastically lowered due to dewing and clouding of the reflecting surface due to a change in the ambient temperature. The dew on the reflecting surface causes a random reflection. In order to avoid the clouding of the reflecting surface, it has been proposed to apply silicon or the like to the surface of the reflecting member. This countermeasure, however, cannot prevent condensing of dew onto the lower part of the reflecting surface.
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When the reflecting surface is absorbing, reflectivity at parallel polarization (p) goes through a non-zero minimum at the so-called pseudo-Brewster's angle.
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Fluorescence interference contrast (FLIC) microscopy is a microscopic technique developed to achieve z-resolution on the nanometer scale. FLIC occurs whenever fluorescent objects are in the vicinity of a reflecting surface (e.g. Si wafer). The resulting interference between the direct and the reflected light leads to a double sin2 modulation of the intensity, I, of a fluorescent object as a function of distance, h, above the reflecting surface.
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Near the end of the video game Simon the Sorcerer, the player can use the Magic Mirror in Sordid's tower as a surveillance monitor, using any reflecting surface like a camera.
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The value of q(\alpha) depends on the properties of the reflecting surface, in particular on its roughness. In practice, different approximations are used based on the known or assumed properties of the surface.
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Before it was applied to photography, the concept of circle of confusion was applied to optical instruments such as telescopes. Coddington (1829, 54) quantifies both a circle of least confusion and a least circle of confusion for a spherical reflecting surface.
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A concave mirror diagram showing the focus, focal length, centre of curvature, principal axis, etc. A concave mirror, or converging mirror, has a reflecting surface that is recessed inward (away from the incident light). Concave mirrors reflect light inward to one focal point. They are used to focus light.
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One advantage is that a pinhead mirror can be swiveled to scan a scene or project a scene to different locations. Pinhead mirror technology was protected under US patent 4,948,211 - "Method and Apparatus for Optical Imaging Using a Small, Flat Reflecting Surface" until the patent expired in 2009.
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The observatory is equipped with a single 260 ton radio telescope with a main reflecting surface diameter of 26 metres. The telescope is equipped with radio receivers operating in the microwave band at wavelengths of 18 cm, 13 cm, 6 cm, 4.5 cm, 3.5 cm, 2.5 cm and 1.3 cm.
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A speculum is a circular or oval hand-mirror used predominantly by Etruscan women. Speculum is Latin; the Etruscan word is or . Specula were cast in bronze as one piece or with a tang into which a wooden, bone, or ivory handle fitted. The reflecting surface was created by polishing the flat side.
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Repetition pitch is an unexpected sensation of tonality or pitch that often occurs in nature when a sound is reflected against a sound-reflecting surface (for example: a brick wall), and both the original and the reflected sound arrive at the ear of an observer, but with a short time delay between the two arrivals.
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Reflections in a convex mirror. The photographer is seen reflected at top right A curved mirror is a mirror with a curved reflecting surface. The surface may be either convex (bulging outward) or concave (recessed inward). Most curved mirrors have surfaces that are shaped like part of a sphere, but other shapes are sometimes used in optical devices.
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However, if n-1 > n-2: no phase change. The phase of the reflected electric field has normal incidence the same phase of the electric field impinging at the interface of the reflecting surface. The variation of the reflection phase is continuous between +180◦ to −180◦ relative to the frequency. Zero is crossed at one frequency, where resonance occurs.
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The horizontal line image is then projected onto a diffraction grating, which is a very finely etched reflecting surface that disperses light into its spectra. The diffraction grating is specially constructed and positioned to create a two-dimensional (2D) spectrum image from the horizontal line image. The spectra are projected vertically, i.e., perpendicular to the line image, by the design and arrangement of the diffraction grating.
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Before it became possible to produce glass with acceptably flat surfaces, bronze was a standard material for mirrors. The reflecting surface was typically made slightly convex so that the whole face could be seen in a small mirror. Bronze was used for this purpose in many parts of the world, probably based on independent discoveries. Bronze mirrors survive from the Egyptian Middle Kingdom (2040–1750 BC).
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Lambertian reflectance is the property that defines an ideal "matte" or diffusely reflecting surface. The apparent brightness of a Lambertian surface to an observer is the same regardless of the observer's angle of view. More technically, the surface's luminance is isotropic, and the luminous intensity obeys Lambert's cosine law. Lambertian reflectance is named after Johann Heinrich Lambert, who introduced the concept of perfect diffusion in his 1760 book Photometria.
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In the north-south direction, the telescope operates as a phased-array and is steerable by varying the phase gradients The telescope can be operated in either total power or correlation mode. In each mode, 12 beams are formed; beam 1 is the southernmost beam and beam 12 is the northernmost. These 12-beam systems are useful in sky survey observations. Recently, the reflecting surface of the ORT has been refurbished.
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DHM can operate both in reflection and transmission mode. In reflection mode, the phase shift image provides a relative distance measurement and thus represents a topography map of the reflecting surface. In transmission mode, the phase shift image provides a label-free quantitative measurement of the optical thickness of the specimen. Phase shift images of biological cells are very similar to images of stained cells and have successfully been analyzed by high content analysis software.
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The reflection is caused by the coherent strong interaction of the neutron with atomic nuclei. It can be quantum-mechanically described by an effective potential which is commonly referred to as the Fermi pseudo potential or the neutron optical potential. The corresponding velocity is called the critical velocity of a material. Neutrons are reflected from a surface if the velocity component normal to the reflecting surface is less than or equal to the critical velocity.
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They typically employ prisms and total internal reflection instead of mirrors, because prisms, which do not require coatings on the reflecting surface, are much more rugged than mirrors. They may have additional optical capabilities such as range-finding and targeting. The mechanical systems of submarine periscopes typically use hydraulics and need to be quite sturdy to withstand the drag through water. The periscope chassis may also support a radio or radar antenna.
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These patches can be seen as silver-grey areas over the white Beta cloth of the main suit. Using patches, rather than an entire garment, avoided the flexibility problems with Gemini. The upper areas of the overshoes, the gloves and patches beneath the life support backpack were of Chromel-R. Gold-plated open-weave Chromel-R mesh has also been used as the reflecting surface for compact-folding parabolic antenna on spacecraft.
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In optics, Lambert's cosine law says that the radiant intensity or luminous intensity observed from an ideal diffusely reflecting surface or ideal diffuse radiator is directly proportional to the cosine of the angle θ between the direction of the incident light and the surface normal.RCA Electro-Optics Handbook, p.18 ffModern Optical Engineering, Warren J. Smith, McGraw-Hill, p.228, 256 The law is also known as the cosine emission law or Lambert's emission law.
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Caltech, the University of Hawaii System, and the University of California accept proposals from their own researchers. NASA accepts proposals from researchers based in the United States. Jerry Nelson was the project scientist for the Keck Telescope, and he also contributed to later multi- mirror projects until he died in June 2017. Nelson was behind one of the innovations of the Keck telescope, the use of multiple thin segments acting as one mirror to provide the reflecting surface.
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When using optics with real materials, light will be attenuated at various wavelengths through interference with the medium through which the light traversed. In this sense, material selection may be utilized to selectively filter light according to the wavelengths that are minimally attenuated. To some extent, all real optical systems will suffer from this phenomena. Alternatively, it is also possible to use an oscillating reflecting surface to cause destructive interference with reflected light along a single optical path.
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Feedback is more likely to occur when the hearing aid volume is increased, when the hearing aid fitting is not in its proper position or when the hearing aid is brought close to a reflecting surface (e.g. when using a mobile phone). Adaptive feedback cancellation algorithms are techniques that estimate the transmission path between loudspeaker and microphone(s). This estimate is then used to implement a neutralizing electronic feedback path that suppresses the tonal feedback signal.
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Heiland Densitometer TRDZ 1 A densitometer is a device that measures the degree of darkness (the optical density) of a photographic or semitransparent material or of a reflecting surface. The densitometer is basically a light source aimed at a photoelectric cell. It determines the density of a sample placed between the light source and the photoelectric cell from differences in the readings. Modern densitometers have the same components, but also have electronic integrated circuitry for better reading.
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The reflecting surface reflects most of the light striking it as long as the surface remains uncontaminated by tarnishing or oxidation. Most modern plane mirrors are designed with a thin piece of plate glass that protects and strengthens the mirror surface and helps prevent tarnishing. Historically, mirrors were simply flat pieces of polished copper, obsidian, brass, or a precious metal. Mirrors made from liquid also exist, as the elements gallium and mercury are both highly reflective in their liquid state.
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Another, psychovisually even more accurate, but also more complex method to obtain or specify the saturation is to use a color appearance model like CIECAM02. Here, the chroma color appearance parameter might (depending on the color appearance model) be intertwined with e.g. the physical brightness of the illumination or the characteristics of the emitting/reflecting surface, which is more sensible psychovisually. The CIECAM02 chroma C, for example, is computed from a lightness J in addition to a naively-evaluted color-magnitude t.
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In audio signal processing and acoustics, echo is a reflection of sound that arrives at the listener with a delay after the direct sound. The delay is directly proportional to the distance of the reflecting surface from the source and the listener. Typical examples are the echo produced by the bottom of a well, by a building, or by the walls of an enclosed room and an empty room. A true echo is a single reflection of the sound source.
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E-ELT mirror segments under test Telescopes and other precision instruments use front silvered or first surface mirrors, where the reflecting surface is placed on the front (or first) surface of the glass (this eliminates reflection from glass surface ordinary back mirrors have). Some of them use silver, but most are aluminium, which is more reflective at short wavelengths than silver. All of these coatings are easily damaged and require special handling. They reflect 90% to 95% of the incident light when new.
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A Slaver stasis field creates a bubble of space/time disconnected from the entropy gradient of the rest of the universe. Time slows effectively to a stop for an object in stasis, at a ratio of some billions of years outside to a second inside. An object in stasis is invulnerable to anything occurring outside the field, as well as being preserved indefinitely. A stasis field may be recognized by its perfectly reflecting surface, so perfect that it reflects 100% of all radiation and particles, including neutrinos.
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As well as degradation of the dye, failure of a CD-R can be due to the reflective surface. While silver is less expensive and more widely used, it is more prone to oxidation resulting in a non-reflecting surface. Gold on the other hand, although more expensive and no longer widely used, is an inert material, so gold-based CD-Rs do not suffer from this problem. Manufacturers have estimated the longevity of gold-based CD-Rs to be as high as 100 years.
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Anderson et al. (2005) wrote: "synapomorphic characters that link the fossils seeds [of P. splendens] to extant Aldrovanda include hard testa with an outer epidermis of palisade cells and with a smooth, strongly reflecting surface, short micropylar neck, and extruding, pointed chalazal area".Anderson, C.L., K. Bremer & E.M. Friis 2005. American Journal of Botany 92(10): 1737–1748. However, research published by Heřmanová & Kvaček (2010) has cast doubt on this hypothesis. These authors identified the fossilised remains of Palaeoaldrovanda as insect eggs, writing:Heřmanová, Z. & J. Kvaček 2010.
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This type of antenna is called a Hogg or horn-reflector antenna, invented by Alfred C. Beck and Harald T. Friis in 1941. U. S. patent no. 2416675 Horn antenna system, filed November 26, 1941, granted Mar 4, 1947, Alfred C. Beck, Harold T. Friis on Google Patents It was built by David C. Hogg. on Alcatel-Lucent website It consists of a flaring metal horn with a curved reflecting surface mounted in its mouth, at a 45° angle to the long axis of the horn.
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A new generation of telescopes built since the 1980s uses thin, lighter weight mirrors instead. They are too thin to maintain themselves rigidly in the correct shape, so an array of actuators is attached to the rear side of the mirror. The actuators apply variable forces to the mirror body to keep the reflecting surface in the correct shape over repositioning. The telescope may also be segmented into multiple smaller mirrors, which reduce the sagging due to weight that occurs for large, monolithic mirrors.
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Coplanar condition of specular reflection, in which \theta _i = \theta _r. Reflections on still water are an example of specular reflection. Specular reflection, or regular reflection, is the mirror-like reflection of waves, such as light, from a surface. The law of reflection states that a reflected ray of light emerges from the reflecting surface at the same angle to the surface normal as the incident ray, but on the opposing side of the surface normal in the plane formed by the incident and reflected rays.
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Fig.7:Total internal reflection by the water's surface at the shallow end of a swimming pool. The broad bubble-like apparition between the swimmer and her reflection is merely a disturbance of the reflecting surface. Some of the space above the water level can be seen through "Snell's window" at the top of the frame. When standing beside an aquarium with one's eyes below the water level, one is likely to see fish or submerged objects reflected in the water-air surface (Fig.1).
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Instead, IXO's mirrors, like all prior X-ray telescopes, will use grazing incidences, scattering at a very shallow angle. As a result, X-ray telescopes consist of nested cylindrical shells, with their inner surface being the reflecting surface. However, as the goal is to collect as many photons as possible, IXO will have a bigger than 3m diameter mirror. As the grazing angle is a function inversely proportional to photon energy, the higher-energy X-rays require smaller (less than 2 degrees) grazing angles to be focused.
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The printed subjects show a broad spectrum of motives: for example self-portraits, pictures from gallery visitors or objects of daily life. Pistoletto intentionally uses the reflective properties of the steel to produce an interactive dialogue between the viewer and the image in front of them. From an interview in 1963 Pistoletto states the relationship between the viewer, the painting, and the virtual space as “the joining of couples of opposite polarity between the photographic image and what goes on in the virtual space generated by the reflecting surface…”Michelangelo Pistoletto. 2011. Mirror Paintings.
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Evanescent-wave coupling is synonymous with near field interaction in electromagnetic field theory. Depending on the nature of the source element, the evanescent field involved is either predominantly electric (capacitive) or magnetic (inductive), unlike (propagating) waves in the far field where these components are connected (identical phase, in the ratio of the impedance of free space). The evanescent wave coupling takes place in the non-radiative field near each medium and as such is always associated with matter; i.e., with the induced currents and charges within a partially reflecting surface.
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The pellicle mirror of the Canon EOS RT A pellicle mirror (diminutive of pellis, a skin or film) is an ultra-thin, ultra-lightweight semi-transparent mirror employed in the light path of an optical instrument, splitting the light beam into two separate beams, both of reduced light intensity. Splitting the beam allows its use for multiple purposes simultaneously. The thinness of the mirror practically eliminates beam or image doubling due to a non- coincident weak second reflection from the nominally non-reflecting surface, a problem with mirror-type beam splitters.
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There are two common methods to obtaining sound velocity in water using the probe method. Firstly, the main three variables that affect sound velocity may be measured using a Conductivity, Temperature & Depth Probe (CTD Probe). This instrument can determine the salinity, temperature and pressure variables, and then calculate the sound velocity of the water using one of the many formulae available. Secondly, the speed of sound may be directly measured using a small acoustic transducer and a reflecting surface, mounted at a known distance from the acoustic center of the transducer.
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They are used to make disk lasers. The amplification is typically over a narrow range of wavelengths, and requires an external source of power. In X-ray telescopes, the X-rays incide on a highly precise metal surface at almost grazing angles, and only a small fraction of the rays are reflected. In flying relativistic mirrors conceived for X-ray lasers, the reflecting surface is a spherical shockwave (wake wave) created in a low-density plasma by a very intense laser-pulse, and moving at an extremely high velocity.
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The curtain array is a larger version used by shortwave radio broadcasting stations. Reflective array antennas usually have a number of identical driven elements, fed in phase, in front of a flat, electrically large reflecting surface to produce a unidirectional beam of radio waves, increasing antenna gain and reducing radiation in unwanted directions. The larger the number of elements used, the higher the gain; the narrower the beam is and the smaller the sidelobes are. The individual elements are most commonly half wave dipoles, although they sometimes contain parasitic elements as well as driven elements.
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MAGIC (Major Atmospheric Gamma Imaging Cherenkov Telescopes) is a system of two Imaging Atmospheric Cherenkov telescopes situated at the Roque de los Muchachos Observatory on La Palma, one of the Canary Islands, at about 2200 m above sea level. MAGIC detects particle showers released by gamma rays, using the Cherenkov radiation, i.e., faint light radiated by the charged particles in the showers. With a diameter of 17 meters for the reflecting surface, it was the largest in the world before the construction of H.E.S.S. II. The first telescope was built in 2004 and operated for five years in standalone mode.
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The term specular means that light is perfectly reflected in a mirror-like way from the light source to the viewer. Specular reflection is visible only where the surface normal is oriented precisely halfway between the direction of incoming light and the direction of the viewer; this is called the half-angle direction because it bisects (divides into halves) the angle between the incoming light and the viewer. Thus, a specularly reflecting surface would show a specular highlight as the perfectly sharp reflected image of a light source. However, many shiny objects show blurred specular highlights.
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Donald learned of the work of Douglass Howry in the United States that an echo could only return to the probe and be recorded if the echo struck the reflecting surface at right angles, as the laws of optics required. At this point, Tom Brown came on the scene and offered to help. For Brown who was looking at the problem as an engineer in a clinical environment, he felt that the A-scope presentation was incompatible with the nature of the problem. Brown thought the image displayed did not correspond closely enough to the condition to enable a correct diagnosis.
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However, the invention with potentially greatest impact at present is his earliest work on "Glancing- incidence radiation focusing device having a plurality of members with tension-polished reflecting surfaces." This patent, available at Google patents clearly shows the concentric glancing incidence design for X-ray collection. Kantor's innovation, the use of surface tension to achieve a super-smooth reflecting surface is at the heart of the proposed NASA Lynx Observatory, which describes the same physical process as "grazing incidence.". Kantor's work, part of his doctoral project at Columbia University, was supported in part by government funding.
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Stainless steel wires forming the parabolic reflector The Ooty Radio Telescope has been designed and fabricated with domestic Indian technological resources. The ORT was completed in 1970 and continues to be one of the most sensitive radio telescopes in the world. Observations made using this telescope have led to important discoveries and to explain various phenomena occurring in the solar system and in other celestial bodies. The reflecting surface of the telescope is made of 1,100 thin stainless-steel wires running parallel to each other for the entire length of the cylinder and supported on 24 steerable parabolic frames.
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No trace of the pattern can be discerned on the reflecting surface with the naked eye, but minute undulations on the surface are introduced during the manufacturing process and cause the reflected rays of light to form the pattern."Oriental magic mirrors and the Laplacian image" by Michael Berry, Eur. J. Phys. 27 (2006) 109–118, DOI: 10.1088/0143-0807/27/1/012 It is very likely that the practice of image projection via drawings or text on the surface of mirrors predates the very refined ancient art of the magic mirrors, but no evidence seems to be available.
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The CATR is used for microwave and millimeter wave frequencies where the 2 D2/λ far-field distance is large, such as with high-gain reflector antennas. The size of the range that is required can be much less than the size required for a full-size far-field anechoic chamber, although the cost of fabrication of the specially- designed CATR reflector can be expensive due to the need to ensure precision of the reflecting surface (typically less than λ/100 RMS surface accuracy) and to specially treat the edge of the reflector to avoid diffracted waves which can interfere with the desired beam pattern.
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If the collimated beam falls perpendicularly onto a plane reflecting surface, the light is reflected back along its original path and is brought to a focus at a point coincident with the origin point. If the reflector is tilted through an angle θ, the reflected beam is deflected through an angle 2θ, and the image I is displaced laterally from the origin 0.The amount of displacement is given by d=2θf where f is the focal length of the lens, and θ is in radians. Light from an illuminated target graticule at the focus of an objective lens is directed towards the lens by a beam splitter.
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After reflection by a mirror on the workpiece, the light returns through the Autocollimator and passes through the beam splitter, forming an image of the target graticule in the plane of an eyepiece graticule. The eyepiece graticule and the reflected image of the target graticule are viewed simultaneously through the eyepiece. The image of the target graticule is always seen in focus and at constant magnification in the eyepiece, regardless of the distance between the Autocollimator and the reflecting surface. However, at long working distances only a portion of the reflected target graticule may appear in the eyepiece, owing to the failure of obliquely returning rays to enter the Autocollimator.
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Figure 2 A point O (fig. 2) at a finite distance from the axis (or with an infinitely distant object, a point which subtends a finite angle at the system) is, in general, even then not sharply reproduced if the pencil of rays issuing from it and traversing the system is made infinitely narrow by reducing the aperture stop; such a pencil consists of the rays which can pass from the object point through the now infinitely small entrance pupil. It is seen (ignoring exceptional cases) that the pencil does not meet the refracting or reflecting surface at right angles; therefore it is astigmatic (Gr. a-, privative, stigmia, a point).
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The Ooty Radio Telescope (ORT, as it is known) is a cylindrical paraboloid of reflecting surface, 530 m long and 30 m wide, placed on a hill whose slope of about 11 degree in the north-south direction which is the same as the latitude of the location of ORT. This makes it possible to track celestial objects for about 10 hours continuously from their rising in east to their setting in the west by simply rotating the antenna mechanically along its long axis. The telescope is operated at 326.5 MHz (a wavelength of 0.92 m) with 15 MHz usable bandwidth. The large size of the telescope makes it highly sensitive.
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For instance, a snare drum sounds higher pitched than a bass drum though both have indefinite pitch, because its sound contains higher frequencies. In other words, it is possible and often easy to roughly discern the relative pitches of two sounds of indefinite pitch, but sounds of indefinite pitch do not neatly correspond to any specific pitch. A special type of pitch often occurs in free nature when sound reaches the ear of an observer directly from the source, and also after reflecting off a sound-reflecting surface. This phenomenon is called repetition pitch, because the addition of a true repetition of the original sound to itself is the basic prerequisite.
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In electrical engineering, a ground plane is an electrically conductive surface, usually connected to electrical ground. The term has two different meanings in separate areas of electrical engineering. In antenna theory, a ground plane is a conducting surface large in comparison to the wavelength, such as the Earth, which is connected to the transmitter's ground wire and serves as a reflecting surface for radio waves. In printed circuit boards, a ground plane is a large area of copper foil on the board which is connected to the power supply ground terminal and serves as a return path for current from different components on the board.
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The red dots are the wave nodes The interference phenomenon in optics occurs as a result of the wave propagation of light. When light of a given wavelength is reflected back upon itself by a mirror, standing waves are generated, much as the ripples resulting from a stone dropped into still water create standing waves when reflected back by a surface such as the wall of a pool. In the case of ordinary incoherent light, the standing waves are distinct only within a microscopically thin volume of space next to the reflecting surface. Lippmann made use of this phenomenon by projecting an image onto a special photographic plate capable of recording detail smaller than the wavelengths of visible light.
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In this way Photometria demonstrated (rather than assumed) that # Illuminance varies inversely as the square of the distance from a point source of light, # Illuminance on a surface varies as the cosine of the incidence angle measured from the surface perpendicular, and # Light decays exponentially in an absorbing medium. In addition, Lambert postulated a surface that emits light (either as a source or by reflection) in a way such that the density of emitted light (luminous intensity) varies as the cosine of the angle measured from the surface perpendicular. In the case of a reflecting surface, this form of emission is assumed to be the case, regardless of the light's incident direction. Such surfaces are now referred to as "Perfectly Diffuse" or "Lambertian".
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A TLS can be installed in areas where a conventional ILS would not fit or would not function properly, like, for example, an airport that doesn't have a proper reflecting surface for an ILS glideslope because of uneven terrain like steep hills or mountains, or airports that have large buildings like hangars or parking garages that create disruptive reflections that would prevent an ILS localizer from being used.Winner (2002), pp. 3–6. TLS does not even have to be installed at a particular location relative to the runway, but can "offset" its signals from wherever it is installed to appear as if it were at the end of the runway. This makes it much less expensive to install while still providing ILS-class blind-landing approaches.
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It was meant to allow the public to view live video of the Earth from orbit and give researchers the capability to search for near-Earth objects. To protect against damaging environmental factors, Pegaso employs the Space Environment Attenuation Manifold (SEAM/NEMEA), a multi-layer polymer insulation which is designed to block alpha and beta particles, X-ray and gamma radiation, and up to 67% of incoming heat. The insulation additionally provides the spacecraft some degree of protection against EMP and plasma discharge events, and allows Pegaso to retain heat during orbital night. Further thermal control is obtained with a thin sheet of carbon nanotubes layered over a heat-reflecting surface, which helps to equalise the temperature throughout the vehicle.
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Speculum metal found an application in early modern Europe as the only known good reflecting surface for mirrors in reflecting telescopes. In contrast to household mirrors, where the reflecting metal layer is coated on the back of a glass pane and covered with a protective varnish, precision optical equipment like telescopes needs first surface mirrors that can be ground and polished into complex shapes such as parabolic reflectors. For nearly 200 years speculum metal was the only mirror substance that could perform this task. One of the earliest designs, James Gregory’s Gregorian telescope could not be built because Gregory could not find a craftsman capable of fabricating the complex speculum mirrors needed for the design. Isaac Newton was the first to successfully build a reflecting telescope in 1668.
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In other words, it is an image which is located in the plane of convergence for the light rays that originate from a given object. Examples of real images include an image on a cinema screen (the source being the projector, and the screen plays as a diffusely reflecting surface so the image formed on the screen plays as an object to be imaged by human eyes), the image produced on a detector in the rear of a camera, and the image produced on an eyeball retina (the camera and eye focus light through an internal convex lens). In ray diagrams (such as the images on the right), real rays of light are always represented by full, solid lines; perceived or extrapolated rays of light are represented by dashed lines. A real image occurs where rays converge, whereas a virtual image occurs where rays only appear to diverge.
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Renovated tiling in 1900 style In 1996 Saint-Augustin on line 9 was chosen as the trial station for a new renovation style. Its original feature is a new light housing (known as the Bruno-Gaudin light fixture) with a wide wave- shaped reflecting surface which is attached to and follows the curve of the vault, hides the bare fluorescent bulbs seen throughout the metro after World War II, and also hides cables efficiently. The style, which focuses on maximizing the amount of light in the stations and hiding unsightly fixtures, also returns to the classic beveled white tile, which reflects light better than all other types that have been used on the system. For this reason, Bruno-Gaudin can be seen to represent a return to the design charter of the original Métro of 1900, and represents a kind of "neo-CMP" aesthetic.
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A problem with this argument, which Loret acknowledged, is that deities are frequently shown holding the ankh by its loop, and their hands pass through it where the solid reflecting surface of an ankh-shaped mirror would be. Andrew Gordon, an Egyptologist, and Calvin Schwabe, a veterinarian, argue that the origin of the ankh is related to two other signs of uncertain origin that often appear alongside it: the was- sceptre, representing "power" or "dominion", and the djed pillar, representing "stability". According to this hypothesis, the form of each sign is drawn from a part of the anatomy of a bull, like some other hieroglyphic signs that are known to be based on body parts of animals. In Egyptian belief semen was connected with life and, to some extent, with "power" or "dominion", and some texts indicate the Egyptians believed semen originated in the bones.
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Assembly of the telescope The main mirror of AXAF (Chandra) HRC flight unit of Chandra Unlike optical telescopes which possess simple aluminized parabolic surfaces (mirrors), X-ray telescopes generally use a Wolter telescope consisting of nested cylindrical paraboloid and hyperboloid surfaces coated with iridium or gold. X-ray photons would be absorbed by normal mirror surfaces, so mirrors with a low grazing angle are necessary to reflect them. Chandra uses four pairs of nested mirrors, together with their support structure, called the High Resolution Mirror Assembly (HRMA); the mirror substrate is 2 cm-thick glass, with the reflecting surface a 33 nm iridium coating, and the diameters are 65 cm, 87 cm, 99 cm and 123 cm. The thick substrate and particularly careful polishing allowed a very precise optical surface, which is responsible for Chandra's unmatched resolution: between 80% and 95% of the incoming X-ray energy is focused into a one-arcsecond circle.
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Silver lenticular screens, while no longer employed as the standard for motion picture projection, have come back into use as they are ideally suited for modern polarized 3-D projection. The percentage of light reflected from a non- metallic (dielectric) surface varies strongly with the direction of polarization and the angle of incidence; this is not the case for an electric conductor such as a metalReflection 2.2: Fresnel equations for reflection from a dielectric surface (as an illustration of this, sunlight reflected from a horizontal surface such as a reflective road surface or water is attenuated by polarized sunglasses relative to direct light; this is not the case if the light is reflected from a metallic surface). As many 3-D technologies in use today depend upon maintaining the polarization of the images to be presented to each eye, the reflecting surface needs to be metallic rather than dielectric. Additionally, the nature of polarized 3-D projection requires the use of interposed filters, and the overall image is consequently less bright than if it were being normally projected.
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