The Thesis Trilogy, designed from 1994-1999, was envisaged as an adaptable and flexible typographic family on a grand and impressive scale. Moreover, the Thesis font families were born from the dissatisfaction that de Groot felt with the restrictive and inadequate range of typefaces that were in circulation for projects involving corporate identities. The aim of the Thesis family of fonts is to fill a fissure that exists in typography – giving the end user three compatible fonts that can work in unison.

In designing the Thesis font families, de Groot crafted an Interpolation Theory to determine the range of the weights. This theory stated that the optical interpolation b, in the three stems a (thinnest), b (interpolation) and c (thickest), is positioned to the geometric mean of a and c. In other words, b² = ac (as opposed to the linear arithmetic method). Using his theory, de Groot developed the Sans, the Mix, and the Serif. Each font is in visual accord with the others.

de Groot first published The Sans design in 1994. During the next decade-and-a-half, this lovely font has come to typify and embody the sans serif ideal – functional, friendly and multi-purpose.

Reference:
LucasFonts - The Sans

As one of the most sought after font families, The Sans has been adopted by large corporations and organizations around the world. Perhaps the most notable use of The Sans design is by one of the U.S.’ biggest Internet service providers, AOL (America Online). Spain’s major cell phone provide, Movistar, uses the font for posters and advertisements. North American mobile phone provider Sprint Nextel has implemented The Sans design as its corporate typeface. The Dutch roadside assistance organization ANWB uses The Sans design as its official corporate typeface.

Because of its versatility and its ability to blend in with other fonts in the Thesis family, The Sans typeface family is ideal for use both in print and digitally, on-screen. From corporate print and design to national ad campaigns, this font is adaptable to a large number of media applications, including websites and mobile text for a number of handheld devices.