NOVELTY - The photovoltaic concentration technology comprises partially filtering solar irradiation at different incidence angles on a photovoltaic module by an optical filter medium composed of a nanostructure having birefringence properties or by a Bragg mirror realized by the encapsulation of the nanostructure at the time of the encapsulation of solar cells of the photovoltaic module and the encapsulation of the nanostructure with a transparent medium. The optical filter medium is arranged opposite to the photovoltaic module with a slope at an angle defined by (a =q-i).    USE - The technology is useful for photovoltaic concentration on greenhouse (claimed).    ADVANTAGE - The technology improves the spectral response of the photovoltaic module thus increasing the electric production and improving the conversion efficiency of the photovoltaic module.    DETAILED DESCRIPTION - The photovoltaic concentration technology comprises partially filtering solar irradiation at different incidence angles on a photovoltaic module by an optical filter medium composed of a nanostructure having birefringence properties or by a Bragg mirror realized by the encapsulation of the nanostructure at the time of the encapsulation of solar cells of the photovoltaic module and the encapsulation of the nanostructure with a transparent medium. The optical filter medium is arranged opposite to the photovoltaic module with a slope at an angle defined by (a=q -i), where q is angle of inclination of filter in degree, q is angle of inclination of the photovoltaic module in degree, and i is 5-20. The encapsulation of the nanostructure film comprises assembling and combining: a transparent medium-I; an encapsulant-I containing silicone having a spectral response of 200 nm and a transmittance of 95% on the photovoltaic spectral band and an index of refraction of 1.34-1.43; a nanostructure film composed of a first medium having a refraction index of 1.3-1.5 and a second medium having a refraction index of 1.6-2; an encapsulant-II having a spectral response of 350 nm and a transmittance of 93% on the photovoltaic spectral band and an index of refraction of 1.4-1.46; and a transparent medium-II. The transparent medium-I and the transparent medium-II have a transmittance of 92% on the spectral band of 275-1500 nm. The encapsulant I and the encapsulant II are silicone formulations in liquid, gel, or gum form and are polymerizable at a lamination temperature of lower than 130?oC, where the silicone is doped by carbon nanotubes or by diamond in the form of nano powder or by graphite in the form of nano powder or by nano luminophores. The nanostructure is a birefringence optical medium or a Bragg mirror. The optical medium is composed of a first medium having a refraction index of 1.45-1.55 on a spectrum of 200-1400nm and a second medium having a refraction index of 1.6-1.98 a spectrum of 200-1400 nm. Each medium with optical anisotropy is in the form of layer having a thickness of higher than 10 ?A . The nanostructure is defined by a nano-laminate, which has a prismatic shape nanotexture and a pyramidal nanotexture in the depth of the medium I and/or the medium II and in the direction of the plane of the mirror according to the medium I or medium II and according to the level in the nano-laminate.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic view of a photovoltaic concentration technology (Drawing includes non-English language text).