32,821 research outputs found

    Ultraviolet filter

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    Ultraviolet filter of thorium fluoride and cryolite on quartz bas

    Remote sensing of atmospheric winds using a coherent, CW lidar and speckle-turbulence interaction

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    Speckle turbulence interaction has the potential for allowing single ended remote sensing of the path averaged vector crosswind in a plane perpendicular to the line of sight to a target. If a laser transmitter is used to illuminate a target, the resultant speckle field generated by the target is randomly perturbed by the atmospheric turbulence as it propagates back to the location of the transmitter-receiver. When a cross wind is present, this scintillation pattern will move with time across the receiver. A continuous wave (cw) laser transmitter of modest power level in conjunction with optical heterodyne detection was used to exploit the speckel turbulence interaction and measure the crosswind. The use of a cw transmitter at 10.6 microns and optical heterodyne detection has many advantages over direct detection and a double pulsed source in the visible or near infrared. These advantages include the availability of compact, reliable and inexpensive transmitters, better penetration of smoke, dust and fog; stable output power; low beam pointing jitter; and considerably reduced complexity in the receiver electronics

    The selection of random movements as a factor in phototaxis

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    No Abstract.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/50101/1/920150203_ftp.pd

    The reactions of Ranatra to light

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    No Abstract.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/50102/1/920150403_ftp.pd
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