UNIFOCAL SPECTACLE LENS WITH TWO ASPHERICAL FACES

摘要

One surface at least has the same curve radii at the apex. The mean surface refraction value is dependent on the main curve radius at each point. Dependent on the distance of each point from the apex at a constant meridional angle, this value is the maximum or nil. This can be the same for both surfaces, which can be circular and symmetrical. One of the surfaces can have different effects at different sections, so that the lens has an astigmatic effect.