An aspherical lens element to achieve sharp definition even from the maximum aperture, was developed together with the highest-end system camera, the F-1 and the best selling SLR camera at the time, the FTb. The ground and polished glass aspherical surface is applied at the front surface of the second lens element. This aspherical lens makes central and peripheral light converge on a single focusing point to correct aberrations. Thus high contrast definition is obtained even at the maximum aperture of f/1.2. The abbreviation “AL” stands for the “Aspherical Lens”.