See Also: Bertrand lens(medicine)
lens, Bertrand(medicine)
Bertrand (as used in expressions)(encyclopedia)
Russell, Bertrand(dictionary)
Bertrand, Ivan Georges(medicine)
Aristide, Jean-Bertrand(encyclopedia)
Canavan-van Bogaert-Bertrand disease(medicine)
Beauvoir, Simone (Lucie-Ernestine-Marie-Bertrand) de(encyclopedia)
Russell, Bertrand (Arthur William), 3rd Earl Russell(encyclopedia)
Lens(health)

phase 1, noun (oh) and Bertrand lens (medicine)


phase 1, noun (oh)



[Date: 1800-1900; Language: Modern Latin; Origin: phasis, from Greek, 'appearance of a star, phase of the moon', from phanein 'to show, appear']
one of the stages of a process of development or change
::a new drug that is in the experimental phase
phase of
::The first phase of renovations should be finished by January.
in phases
::The work will be carried out in phases.
::It's just a phase he's going through .
out of phase (with sth)
BrE not happening together in the right way
::Nizan's views were out of phase with the political climate of the time.
in phase (with sth)
BrE happening together in the right way
::The electrical work will be carried out in phase with the Other renovations.
technical one of a fixed number of changes in the appearance of the moon or a planet when it is seen from the Earth

Bertrand lens (medicine)


Bertrand lens
<physics> A small, low-power lens, usually on a slide for insertion into the drawtube between analyser and ocular. It is used to observe the back focal plane of the objective so as to examine interference figures or as an aid in achieving interference figures. It is apt to be strongly astigmatic. It is used to image the lamp filament in setting up Kohler illumination as well as for centreing dispersion staining stops to the substage aperture diaphragm.