Scientists have developed an impossibly thin telescope lens that addresses a key astronomical challenge in a new study funded ...

Though still only in the prototype stage, this flat lens could one day be used on space telescopes, and perhaps even on ...

Pronounced "fraynel zone." The pattern of electromagnetic radiation that is created by a transmitting station from its antenna to receiving antennas. It is in the shape of an ellipsoid ...

One existing type, called a Fresnel zone plate (FZP), uses concentric ridges to focus light, rather than a thick, curved ...

IN this communication I give a somewhat more general discussion of the Fresnel drag coefficient than is usual, with the view of clarifying the relation between two expressions for it, which occur ...