The OptoTech SD progressive lens design spreads the unwanted astigmatism across larger areas of the lens surface, thereby reducing the overall magnitude of blur at the expense of narrowing the zones of perfectly clear vision. The astigmatic error may even affect the distance zone. Consequently, softer progressive lenses generally show the following characteristics: Narrower distance zones, wider near zones, and lower, more slowly increasing levels of astigmatism (widely spaced contours). The max. amount of unwanted astigmatism is reduced to an incredible level of approx. 75% of the addition power.This design variant is partly applicable for modern working places.