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    The accuracy and the measurement range of surface profilometry by wavelength scanning interferometry applied to diffusely reflecting surfaces are investigated. The influences of surface roughness and the imaging system in the interferometer are theoretically analyzed by derivation of the autocorrelation function of interferograms arising from wavelength scanning. By using a dye laser with a tuning range of 4.2 nm to a yield resolution of 39.1 μm, we have observed interferograms and their Fourier transforms and autocorrelations to study effects of defocusing and the size ratio of speckle to the CCD pixel for a plane diffuse object positioned normal to the incident beam.
    Speckle imaging
    Decorrelation
    Citations (35)
    Optically recorded Fresnel zone plates have proper spatial frequency characteristics for use as a laser scanner. Such grating scanners can easily be made and can scan over large cone angles with, however, severe aberrations of the diffracted laser beam at large deflection angles. Optically recorded Fresnel zone plates for laser beam scanning are investigated, and their aberration properties are analyzed. A method for removing the wavefront error caused by this type of zone plate is discussed, and the feasibility of the method is demonstrated.
    Zone plate
    Fresnel zone
    Laser Scanning
    Fresnel number
    Diffraction efficiency
    Citations (18)
    A large-aperture interferometer has been devised by adding a local reference-beam-generating interferometer to a schlieren system. Two versions of the interferometer were demonstrated, one employing 12.7-cm diam schlieren optics, the other employing 30.48-cm diam parabolic mirrors in an off-axis system. In the latter configuration, a cylindrical lens was introduced near the light source to correct for astigmatism. A zone plate was a satisfactory decollimating element in the reference-beam arm of the interferometer. Attempts to increase the flux and uniformity of irradiance in the reference beam by using a diffuser are discussed.
    Aperture (computer memory)
    Diffuser (optics)
    Reference beam
    Light beam
    Citations (11)
    A system of large rectangular Fresnel lenses has been used in the laser alignment system for the SLAC two-mile accelerator. The alignment system consists of a He-Ne laser light source, a photoelectric detector, and the lenses, one of which is located at each of 297 points which are to be aligned. Each lens has the proper focal length to focus the laser to a point image at the detector. When the alignment at a certain point is to be checked, the image from that lens is scanned by the detector. The image is found to be displaced from its normal position by an amount equal to the product of the position error and the magnification of the lens. The alignment sensitivity is +/-0.0025 mm. The targets are enclosed in a 60-cm diam evacuated light pipe to avoid atmospheric disturbances.
    Fresnel lens
    Stray light
    Position (finance)
    Point spread function
    Citations (54)
    In a previous paper by Cebrian et al. [Opt. Eng.53, 092006 (2014)OPEGAR0091-328610.1117/1.OE.53.9.092006], the knife-edge interferometer (KEI) was used for testing lenses with a collimated beam illuminating the lens. In this paper, a 2f scheme is used to test lenses, eliminating the use of a collimation beam, and testing, for the first time, concave reflecting (spherical and parabolic) surfaces at the center of curvature with KEI.
    Collimated light
    Parabolic reflector
    Curved mirror
    Citations (1)
    We report a laser writing system for fabrication of diffractive optical elements with He-Cd laser. The wavelength of the light source is 441.6 nm. The output beam is collimated into parallel light with uniform intensity distribution after passing through the spatial filter with a pinhole of 25 um and the collimating device. A microscopy objective lens with numerical aperture (NA) of 0.65 is used to focus the beam into a small diffraction spot. Any pattern can be written with this system. Experimental results are presented. The written gratings and the phase patterns were verified with a conventional optical microscopy and the Taylor Hobson equipment.
    Collimated light
    Pinhole (optics)
    Aperture (computer memory)
    Numerical aperture
    Spatial filter
    Citations (1)
    A simple diagnostic characterizing one-dimensional chromatic aberrations in a broadband beam is introduced. A Ronchi grating placed in front of a spectrometer entrance slit provides spectrally coupled spatial phase information. The radial-group delay of a refractive system and the pulse-front delay of a wedged glass plate have been characterized accurately in a demonstration experiment.
    Chromatic aberration
    Spatial frequency
    Shearing interferometer
    Citations (11)
    Бұл зерттеужұмысындaКaно моделітурaлы жәнеоғaн қaтыстытолықмәліметберілгенжәнеуниверситетстуденттерінебaғыттaлғaн қолдaнбaлы (кейстік)зерттеужүргізілген.АхметЯссaуи университетініңстуденттеріүшін Кaно моделіқолдaнылғaн, олaрдың жоғaры білімберусaпaсынa қоятынмaңыздытaлaптaры, яғнисaпaлық қaжеттіліктері,олaрдың мaңыздылығытурaлы жәнесaпaлық қaжеттіліктерінеқaтыстыөз университетінқaлaй бaғaлaйтындығытурaлы сұрaқтaр қойылғaн. Осы зерттеудіңмaқсaты АхметЯсaуи университетіндетуризмменеджментіжәнеқaржы бaкaлaвриaт бaғдaрлaмaлaрыныңсaпaсынa қaтыстыстуденттердіңқaжеттіліктерінaнықтaу, студенттердіңқaнaғaттaну, қaнaғaттaнбaу дәрежелерінбелгілеу,білімберусaпaсын aнықтaу мен жетілдіружолдaрын тaлдaу болыптaбылaды. Осы мaқсaтқaжетуүшін, ең aлдыменКaно сaуaлнaмaсы түзіліп,116 студенткеқолдaнылдыжәнебілімберугежәнеоның сaпaсынa қaтыстыстуденттердіңтaлaптaры мен қaжеттіліктерітоптықжұмыстaрaрқылыaнықтaлды. Екіншіден,бұл aнықтaлғaн тaлaптaр мен қaжеттіліктерКaно бaғaлaу кестесіменжіктелді.Осылaйшa, сaпa тaлaптaры төрт сaнaтқa бөлінді:болуытиіс, бір өлшемді,тaртымдыжәнебейтaрaп.Соңындa,қaнaғaттaну мен қaнaғaттaнбaудың мәндеріесептелдіжәнестуденттердіңқaнaғaттaну мен қaнaғaттaнбaу деңгейлерінжоғaрылaту мен төмендетудеосытaлaптaр мен қaжеттіліктердіңрөліaйқын aнықтaлды.Түйінсөздер:сaпa, сaпaлық қaжеттіліктер,білімберусaпaсы, Кaно моделі.
    Citations (0)
    The nationally-recognized Susquehanna Chorale will delight audiences of all ages with a diverse mix of classic and contemporary pieces. The ChoraleAƒÂƒA‚ƒAƒÂ‚A‚ƒAƒÂƒA‚‚AƒÂ‚A‚ƒAƒÂƒA‚ƒAƒÂ‚A‚‚AƒÂƒA‚‚AƒÂ‚A‚ƒAƒÂƒA‚ƒAƒÂ‚A‚ƒAƒÂƒA‚‚AƒÂ‚A‚‚AƒÂƒA‚ƒAƒÂ‚A‚‚AƒÂƒA‚‚AƒÂ‚A‚¢AƒÂƒA‚ƒAƒÂ‚A‚ƒAƒÂƒA‚‚AƒÂ‚A‚ƒAƒÂƒA‚ƒAƒÂ‚A‚‚AƒÂƒA‚‚AƒÂ‚A‚‚AƒÂƒA‚ƒAƒÂ‚A‚ƒAƒÂƒA‚‚AƒÂ‚A‚‚AƒÂƒA‚ƒAƒÂ‚A‚‚AƒÂƒA‚‚AƒÂ‚A‚€AƒÂƒA‚ƒAƒÂ‚A‚ƒAƒÂƒA‚‚AƒÂ‚A‚ƒAƒÂƒA‚ƒAƒÂ‚A‚‚AƒÂƒA‚‚AƒÂ‚A‚‚AƒÂƒA‚ƒAƒÂ‚A‚ƒAƒÂƒA‚‚AƒÂ‚A‚‚AƒÂƒA‚ƒAƒÂ‚A‚‚AƒÂƒA‚‚AƒÂ‚A‚™s performances have been described as AƒÂƒA‚ƒAƒÂ‚A‚ƒAƒÂƒA‚‚AƒÂ‚A‚ƒAƒÂƒA‚ƒAƒÂ‚A‚‚AƒÂƒA‚‚AƒÂ‚A‚ƒAƒÂƒA‚ƒAƒÂ‚A‚ƒAƒÂƒA‚‚AƒÂ‚A‚‚AƒÂƒA‚ƒAƒÂ‚A‚‚AƒÂƒA‚‚AƒÂ‚A‚¢AƒÂƒA‚ƒAƒÂ‚A‚ƒAƒÂƒA‚‚AƒÂ‚A‚ƒAƒÂƒA‚ƒAƒÂ‚A‚‚AƒÂƒA‚‚AƒÂ‚A‚‚AƒÂƒA‚ƒAƒÂ‚A‚ƒAƒÂƒA‚‚AƒÂ‚A‚‚AƒÂƒA‚ƒAƒÂ‚A‚‚AƒÂƒA‚‚AƒÂ‚A‚€AƒÂƒA‚ƒAƒÂ‚A‚ƒAƒÂƒA‚‚AƒÂ‚A‚ƒAƒÂƒA‚ƒAƒÂ‚A‚‚AƒÂƒA‚‚AƒÂ‚A‚‚AƒÂƒA‚ƒAƒÂ‚A‚ƒAƒÂƒA‚‚AƒÂ‚A‚‚AƒÂƒA‚ƒAƒÂ‚A‚‚AƒÂƒA‚‚AƒÂ‚A‚œemotionally unfiltered, honest music making, successful in their aim to make the audience feel, to be moved, to be part of the performance - and all this while working at an extremely high musical level.AƒÂƒA‚ƒAƒÂ‚A‚ƒAƒÂƒA‚‚AƒÂ‚A‚ƒAƒÂƒA‚ƒAƒÂ‚A‚‚AƒÂƒA‚‚AƒÂ‚A‚ƒAƒÂƒA‚ƒAƒÂ‚A‚ƒAƒÂƒA‚‚AƒÂ‚A‚‚AƒÂƒA‚ƒAƒÂ‚A‚‚AƒÂƒA‚‚AƒÂ‚A‚¢AƒÂƒA‚ƒAƒÂ‚A‚ƒAƒÂƒA‚‚AƒÂ‚A‚ƒAƒÂƒA‚ƒAƒÂ‚A‚‚AƒÂƒA‚‚AƒÂ‚A‚‚AƒÂƒA‚ƒAƒÂ‚A‚ƒAƒÂƒA‚‚AƒÂ‚A‚‚AƒÂƒA‚ƒAƒÂ‚A‚‚AƒÂƒA‚‚AƒÂ‚A‚€AƒÂƒA‚ƒAƒÂ‚A‚ƒAƒÂƒA‚‚AƒÂ‚A‚ƒAƒÂƒA‚ƒAƒÂ‚A‚‚AƒÂƒA‚‚AƒÂ‚A‚‚AƒÂƒA‚ƒAƒÂ‚A‚ƒAƒÂƒA‚‚AƒÂ‚A‚‚AƒÂƒA‚ƒAƒÂ‚A‚‚AƒÂƒA‚‚AƒÂ‚A‚ Experience choral singing that will take you to new heights!
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