iseikonic

Some prescription houses offer lenses specifically designed to increase magnification while leaving the refractive power unaffected; such lenses are referred to as iseikonic or size lenses.

Alternatively, an iseikonic ('sized') lens may be dispensed in order to increase the retinal image size of the least positive eye, although the result may be cosmetically unacceptable due to the lens thickness.

In rare cases, iseikonic spectacle lenses, with specific values of magnification, can be used to correct aniseikonia.