Abstract: The present invention relates to a method of manufacture of an optical lens providing refractive index modulation, characterized in that, starting from a lens of transparent hydrophilic polymer preferably of the hydrogel type, which has previously been shaped, the lens is impregnated with a photopolymerizable composition containing at least one monomer and a photoinitiator, which are in solution in water in the case of a hydrogel, the impregnated lens is subjected to locally modulated irradiation so as to cause local selective polymerization of the monomer, whereupon the excess non-hardened photoinitiator and non-pulverizable monomer is removed.

Abstract: The manufacture of an artificial optical lens having any given power profile starts from an artificial optical lens having a different power profile. A physical-chemical treatment method modifies the power profile to obtain a required power profile. A rotating mask is used for spatial modulation of the energy flux.

Abstract: Disclosed is an ophthalmic lens which characteristically comprises at least two concentric regions having diffractive components with different phase profiles in order to use different orders of diffraction. The diffractive components may be formed by holograms in relief or index holograms.

Abstract: A diffractive contact lens in relief includes a smoothing layer (50) of optically transparent material having a smooth outside surface (51) and placed over the optical surface (16) in relief so as to immerse the relief.

Abstract: The present invention relates to an optical lens for correcting astigmatism. It includes diffractive components whose outlines are delimited by conic section curves having non-degenerate centers. More precisely, in accordance with the invention, the lens includes adjacent diffractive components having hyperbolic or elliptical outlines with a periodicity in r.sup.2 in two mutually orthogonal directions x and y intersecting on the axis of the lens and coinciding with the main axes of the hyperbolas or of the ellipses, which are determined respectively by the equations: .DELTA.r.sub.x.sup.2 =2.lambda..vertline.f.sub.x .vertline.; and .DELTA.r.sub.y.sup.2 =2.lambda..vertline.f.sub.y .vertline.; in which: .DELTA.r.sub.x.sup.2 represents the periodicity in r.sup.2 along the x direction; .DELTA.r.sub.y.sup.2 represents the periodicity in r.sup.2 along the y direction; .lambda. represents the mean utilization wavelength; f.sub.x represents the desired focal length in the X direction; and f.sub.