Ophthalmic lenses with heterocyclic chromene compounds

An ophthalmic lens comprising a transparent organic polymer material and at least one photochromic compound which is of the original formula:

• ##STR17## wherein R.sup.a, R.sup.b and R.sup.c denote, independently of each other, a hydrogen atom, an alkyl group, an aryl group, an OR, SR, COR or COOR group, where R denotes a hydrogen atom, an alkyl group or an aryl group, an amino group of formula NR.sub.1 R.sup.2 where R.sup.1 and R.sup.2 denote, independently of each other, a hydrogen atom, an alkyl group, a cycloalkyl group or an aryl group;
• a halogen atom;
• a mono- or polyhaloalkyl group;
• or an NO.sub.2, CN or SCN group;
• n and m denote integers from 1 to 5;
• p is equal to 1 or 2;
• R.sup.a, R.sup.b and R.sup.c may have different meanings when m, n and p are greater than 1;
• and H is an aromatic heterocycle having the general formula:
• ##STR18## wherein:
• X, Y and Z represent independently of each other, a CR.sub.8 radical or a nitrogen atom, and one or two of X, Y and Z is a nitrogen atom and R.sub.8 is selected from the group consisting of hydrogen, C.sub.1 -C.sub.6 alkyl and phenyl;
• and R.sub.4 is selected from the group consisting of hydrogen, C.sub.1 -C.sub.6 alkyl and phenyl, said at least one photochromic compound being present in a sufficient amount to enable the ophthalmic lens to change color upon exposure to ultraviolet radiation.