X-Nico

2 unusual facts about achromatic lens


Achromatic lens

The choice of glass gives the mean refractive index, often written as n d (for the refractive index at the Fraunhofer "d" spectral line wavelength), and the Abbe number V (for the reciprocal of the glass dispersion).

Simon Plössl

His major achievement at the time was the improvement of the achromatic microscope objective.


Alexander Aubert

Amongst the latter were a Dollond 46-inch achromatic, aperture 3¾ inches, and the one Cassegrain reflector constructed by Short, of 24 inches focus and 6 aperture, known among opticians as 'Short's Dumpy.'

Borescope

Optical systems in rigid borescopes can be of 3 basic types: Harold Hopkins rod lenses, achromatic doublets and gradient index rod lenses.


see also