PUPIL PHOTOCHROMIC CONTACT LENSES HAVING DESIRABLE OPTICAL PROPERTIES AND COMFORTABLE TO WEAR Russian patent published in 2016 - IPC G02C7/04 G02B1/04 

FIELD: physics, optics.

SUBSTANCE: method for making photochromic, hydrogel contact lenses includes dosing the first hydrogel lens composition on a front mould par, the said composition comprising a contact lens monomer and a photochromic material; dosing the second hydrogel lens composition on top of the first composition, wherein the first composition has a viscosity greater than that of the second composition; positioning the second mould part in the immediate vicinity of the first mould part thereby forming a cavity with the first composition and the second composition, and curing the first and second compositions to form a hydrogel contact lens having an actual sagittal depth within about 100 mcm of a design sagittal depth. In the first version, the first and second composition, when cured, have expansion factors which are within 10% of each other. In the second version, the lens has a tensile modulus of less than about 1379.0 kPa.

EFFECT: reduced deformation and optical distortions and high wearing comfort.

15 cl, 10 dwg, 7 tbl