A method of manufacturing an ophthalmic lens having a desired optical function, the ophthalmic lens comprising a starting optical system having a first main refractive index and a complementary optical element having a second main refractive index, the difference between the first main refractive index and the second main refractive index being superior or equal to 0.1, each of the starting optical system and of the complementary optical element providing a part of the optical function of the ophthalmic lens, the ophthalmic lens defining a thickness axis, the method comprising: - a step of providing the starting optical system, the starting optical system having a first optical function, - a step of providing a transition layer intended to be disposed between the starting optical system and the complementary optical element, the transition layer aiming at reducing unwanted reflection caused by the mismatch between the first and the second main refractive index, the transition layer having a transition optical function, said step of providing the transition layer comprising: o providing at least two materials with a first and a second transition refractive indexes, respectively; o distributing said at least two materials so that the amount of each of said at least two materials varying in the transition layer along the thickness axis, said at least two materials being distributed in the transition layer so that first and second transition refractive indexes form a refractive index gradient between first and second main refractive indexes along the thickness axis, and - a step of additively manufacturing the complementary optical element on the transition layer, the complementary optical element having a second optical function, the second optical function being predetermined as a function of the first optical function and of the transition optical function in order to match the desired optical function of the ophthalmic lens. - a step of providing the starting optical system, the starting optical system having a first optical function, - a step of providing a transition layer intended to be disposed between the starting optical system and the complementary optical element, the transition layer aiming at reducing unwanted reflection caused by the mismatch between the first and the second main refractive index, the transition layer having a transition optical function, said step of providing the transition layer comprising: o providing at least two materials with a first and a second transition refractive indexes, respectively; o distributing said at least two materials so that the amount of each of said at least two materials varying in the transition layer along the thickness axis, said at least two materials being distributed in the transition layer so that first and second transition refractive indexes form a refractive index gradient between first and second main refractive indexes along the thickness axis, and o providing at least two materials with a first and a second transition refractive indexes, respectively; o distributing said at least two materials so that the amount of each of said at least two materials varying in the transition layer along the thickness axis, said at least two materials being distributed in the transition layer so that first and second transition refractive indexes form a refractive index gradient between first and second main refractive indexes along the thickness axis, and - a step of additively manufacturing the complementary optical element on the transition layer, the complementary optical element having a second optical function, the second optical function being predetermined as a function of the first optical function and of the transition optical function in order to match the desired optical function of the ophthalmic lens.