NBS Technical NoteU.S. Government Printing Office, 1981 |
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Page 2
... aperture . a . Uniformity over aperture . b . Pulse - to - pulse energy . Apparatus and Procedures Before going on to discuss the entries in Table 1 in detail , we must describe the experimental apparatus . We obtained six LEDs whose ...
... aperture . a . Uniformity over aperture . b . Pulse - to - pulse energy . Apparatus and Procedures Before going on to discuss the entries in Table 1 in detail , we must describe the experimental apparatus . We obtained six LEDs whose ...
Page 21
... aperture , we roughly collimated the emission from the diodes with a lens whose focal length was about 20 cm and diameter about 10 cm . We pulsed the LEDs and scanned the detector across the aperture of the lens . This procedure does ...
... aperture , we roughly collimated the emission from the diodes with a lens whose focal length was about 20 cm and diameter about 10 cm . We pulsed the LEDs and scanned the detector across the aperture of the lens . This procedure does ...
Page 22
... aperture . The LEDs with the ruby lenses are uniform to ± 5 % over about an F / 4 aperture . We also used a uniform large - area silicon detector to measure the approximate power each LED radiated into an F / 8 cone . These results are ...
... aperture . The LEDs with the ruby lenses are uniform to ± 5 % over about an F / 4 aperture . We also used a uniform large - area silicon detector to measure the approximate power each LED radiated into an F / 8 cone . These results are ...
Page 25
... aperture with a given dia- meter . On the other hand , a low beam divergence will require the designer to sacrifice energy by using a low - aperture collimating lens or a spatial filter to reduce the apparent diameter of the source ...
... aperture with a given dia- meter . On the other hand , a low beam divergence will require the designer to sacrifice energy by using a low - aperture collimating lens or a spatial filter to reduce the apparent diameter of the source ...
Page 39
... aperture of the receiver , we may set do equal to the ( finite ) area of the receiver and implicitly integrate Eq . ( El ) with respect to . The result is that аф = D2 / 422 . ( E3 ) We are more likely to be interested in energy than in ...
... aperture of the receiver , we may set do equal to the ( finite ) area of the receiver and implicitly integrate Eq . ( El ) with respect to . The result is that аф = D2 / 422 . ( E3 ) We are more likely to be interested in energy than in ...
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antenna attenuation Backscatter response backscatter signal backscatter signature beam beam divergence Bureau of Standards C3Hg calculated calibration capture fractions components coupling loss dBV/m densimeter DEPARTMENT OF COMMERCE detector diameter diode dipole electric field electronic engineering equation experimental far-field fault signature Federal field distortion due field intensity field strength Figure frequency function graded-index fiber Haynes Hiza IEEE Trans index fibers input instrument isotropic Laboratory laser laser diode leaky modes lens logarithmic Magnetic field distortion measurement metering unit methane microbending MIXTURE mode filter mole fraction N₂ National Bureau near-field numerical aperture optical fiber OTDR output parameters peak percent perfectly conducting cylinder potentiometer pulse radiation angle radiation monitor range Rayleigh scattering Report Resistor scan Science sensor step-index fiber switch Table Tech technical Technology temperature transverse electromagnetic cell U.S. DEPARTMENT voltage waveguide wavelength ZERO
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