A multifocal ophthalmic device comprising a lens body being formed with a plurality of concentric annular zones having surfaces separated by slanted steps having surfaces, wherein said surfaces of said concentric zones effect both diffraction and refraction of incident light, while said surfaces of said steps are substantially devoid of any diffractive or refractive power, and wherein at least one zone of said plurality of concentric zones has a diffraction pattern formed on a respective surface such that a diffractive power of said surface gradually decreases across said surface, and wherein said lens body comprises a co-polymeric composition which comprises a polymeric backbone composed of a plurality of backbone units covalently linked to one another, said backbone units being derived from a pre-polymerization mixture of monomers which comprises: a first aromatic acrylate monomer, characterized as forming a first homopolymer having a refractive index that ranges from 1.50 to 1.53, when measured according to a standard procedure, and having a Tg, measured according to a standard procedure; a second aromatic acrylate monomer, characterized as forming a second homopolymer having a Tg lower by a range of 2 °C to 30 °C than said Tg of said first homopolymer, when measured according to a standard procedure; a third monomer, characterized as forming a third homopolymer having a Tg lower than 35 °C; a fourth monomer, characterized as forming a fourth homopolymer which is capable of absorbing water to at least 20 % of the total weight of said fourth homopolymer when meaqsured according to a standard procedure; and a fifth monomer, being a crosslinking monomer, wherein: a concentration of said first aromatic acrylate monomer ranges from 50 % to 60 % of the total weight of the composition; a concentration of said second aromatic acrylate monomer ranges from 15 % to 20 % of the total weight of the composition; a concentration of said third monomer ranges from 10 % to 15 % of the total weight of the composition; a concentration of said fourth monomer ranges from 5 % to 10 % of the total weight of the composition; and a concentration of said fifth monomer ranges from 2 % to 5 % of the total weight of the composition. a first aromatic acrylate monomer, characterized as forming a first homopolymer having a refractive index that ranges from 1.50 to 1.53, when measured according to a standard procedure, and having a Tg, measured according to a standard procedure; a second aromatic acrylate monomer, characterized as forming a second homopolymer having a Tg lower by a range of 2 °C to 30 °C than said Tg of said first homopolymer, when measured according to a standard procedure; a third monomer, characterized as forming a third homopolymer having a Tg lower than 35 °C; a fourth monomer, characterized as forming a fourth homopolymer which is capable of absorbing water to at least 20 % of the total weight of said fourth homopolymer when meaqsured according to a standard procedure; and a fifth monomer, being a crosslinking monomer, a concentration of said first aromatic acrylate monomer ranges from 50 % to 60 % of the total weight of the composition; a concentration of said second aromatic acrylate monomer ranges from 15 % to 20 % of the total weight of the composition; a concentration of said third monomer ranges from 10 % to 15 % of the total weight of the composition; a concentration of said fourth monomer ranges from 5 % to 10 % of the total weight of the composition; and a concentration of said fifth monomer ranges from 2 % to 5 % of the total weight of the composition.