beam diameter


Also found in: Dictionary, Wikipedia.

beam diameter

[′bēm dī‚am·əd·ər]
(optics)
The distance between points on opposite sides of a light beam at which the power per unit area drops to 1/ e (0.37) times its maximum value.
References in periodicals archive ?
Boone and Crockett's scoring system can reveal if a particular buck is charging forward or stuck in neutral, but the beam diameter right above the burr reveals true health and genetic potential.
Power mode" is when the beam diameter is less than the defining aperture of the TSI instrument (or NIST irradiance standard); "irradiance mode" is when the input beam diameter is greater than the diameter of the defining aperture.
Early on, the beam diameters of lasers were 300 lam or more, and the mask for the laser process was etched for these tiny holes, but not with the best yield.
Farmland Antler Beam Diameter Antler Points Mean Mean n (mm) SE n (#) SE 1981-82 (1) 356 24.
Establishing a microprobe protocol for measurement of St/Ca ratios in otoliths involves a balancing act of counting times, beam current, and beam diameter.
Due to the double condenser lens of the GEMINI[R] II column within the MERLIN, the beam diameter is minimized to the extreme, resulting in high spatial resolution of the WDS analysis.
Features include one-handed, full-range adjustment of beam diameter and light strength, 9 fully multicoated lenses, and more than 7 hours of battery power.
LightPath Technologies introduces 6 new asphere lenses, including three Kodak equivalent aspheric lenses and three LightPath exclusive large numerical aperture, large beam diameter aspheric lenses.
At the NG-6 end station, the highly collimated cold neutron beam exits the guide through a thin Mg window and travels through 79 cm of air to an aperture that defines the beam diameter.
Supply of a pulsed laser source, modulated in wavelength in a wide spectral window, high average power, small beam diameter and reduced ellipticity.
Because the fiber is used between the input and output lenses, the output beam diameter will remain steady -- even when there are fluctuations to the input beam diameter.