Abstract: A process for manufacturing an optical element comprising a first step of spinning a circular sheet of a first metallic material for it to adhere to a rotating matrix and form a shell; a second step of assembling the shell on a temporary support; and at least a third step of diamond turning the shell by means of a diamond tool to obtain an optical surface.

Abstract: An apparatus for non-invasive inspection of solid bodies by muon imaging, comprising a receiver (3) adapted to intercept a muon flux associated with cosmic rays passing through a portion of a body to be inspected, sensor means (4) adapted to detect the amount of photons or Cherenkov radiation associated with the intercepted muon flux, electronic processing means adapted to reconstruct energy and direction of the muon flux incident the portion of the body to be inspected to calculate the local density thereof. The receiver (3) comprises an optical device (5) provided with at least one receiving surface (6) having reflecting and/or diffractive properties adapted to convey the Cherenkov radiation associated with muons toward the sensor means (4), these latter comprising a multipixel detection chamber (8) adapted to provide an annular image of the muon having radius and position variable as a function of the energy and direction of muon flux.