Abstract

The origins of varifocal spectacle lenses go hack a long way, the patent of Aves (1907) Being generally accepted, as the first practical design of lens. Varifocals as we know them today Began with the Varilux design from Bernard Maitenaz in the late nineteen-fifties. The original Varilux demonstrated three main features:

1) Stable distance power over the upper half of the lens.

2) Starting near the mid point of the lens, a narrow central progressive power corridor leads into a stable reading area at the bottom of the lens.

3) Complete 'invisibility' of the power zones giving rise to a single vision type appearance.

© 1991 Optical Society of America