Multifocal diffractive ophthalmic lenses with evenly spaced echelettes

A multifocal ophthalmic lens, comprising:

• a base lens having a base curvature corresponding to a base power;
• and
• a diffractive structure formed on a first surface of the base lens generating a zero-order diffraction having a distance vision focal point determined by the base power, a first-order diffraction, a second-order diffraction having an intermediate vision focal point, and a third-order diffraction corresponding to a near vision focal point, wherein:
• the diffractive structure comprises a central zone comprising a first echelette at a center of the diffractive structure and a plurality of annular echelettes surrounding the first echelette,
• at least two echelettes of the plurality of annular echelettes have different sag profiles relative to each other,
• a radial spacing of each of the plurality of annular echelettes is constant throughout the diffractive structure,
• diffraction efficiency of the zero-order diffraction is between 35% and 50%,
• diffraction efficiency of the first-order diffraction is between 3% and 10%,
• diffraction efficiency of the second-order diffraction is between 10% and 15%, and
• diffraction efficiency of the third-order diffraction is between 15% and 25%.

A method for configuring an ophthalmic lens, comprising:

• computing a constant radial spacing for each of a plurality of annular echelettes, to be formed on a first surface of a base lens, based on a predetermined add power, wherein:
• the base lens comprises a central zone comprising a first echelette at a center of the base lens, and
• the plurality of annular echelettes surround the first echelette,
• at least two echelettes of the plurality of annular echelettes have different sag profiles relative to each other, and
• forming the plurality of annular echelettes or causing the plurality of annular echelettes to be formed on the ophthalmic lens based on the computed constant radial spacing.