the technique of establishing precise reference lines and planes by means of telescopic sights, especially for the purpose of aligning machinery, machine-shop work, etc.
- Optical time domain reflectometry
Measurement of the elapsed time and intensity of light reflected on optical fibre using an optical time domain reflectometer. The reflectometer can compute the distance to problems on the fibre such as attenuation and breaks, making it a useful tool in optical network trouble-shooting. (1995-02-01)
noun, (used with a singular or plural verb) 1. a laser device used to study, manipulate, or trap a microscopic object, as a microorganism or cell, with nanometer precision.
noun 1. a wedge-shaped filter whose transmittance decreases from one end to the other: used as an exposure control device in sensitometry.
noun, Crystallography. 1. (in a crystal exhibiting double refraction) the direction or directions, uniaxial or biaxial, respectively, along which this phenomenon does not occur. noun 1. the direction in a uniaxial crystal or one of the two directions in a biaxial crystal along which a ray of unpolarized light may pass without undergoing double refraction […]