In order to ensure a correct flow of information, he started to work following three directions of research: lenses, prisms and filters. Lenses had been adopted in all functional, behavioural, and preventive approaches, but had not given the desired results, while filters had been used in some experiments in the United States with positive effects.

Prisms, however, represented a possible new frontier. Marco Grassi, with his experience as a manufacturer and designer of materials for visual rehabilitation, began to experiment, hypothesizing the possible effects of a prism that would move the light as little as possible, working more on its ‘diffusion’ within the peripheral retinal surface.

Starting from prisms with less than 1 prism diopter, the experimentation continued with decimal steps; as the magnitude was lowered, the response was faster and with higher acceptance and perceptual openness.

What followed was a long work to find the exact centesimal power to produce the opening of the sensory system without destabilizing it.

Thanks to this twenty-year research and the continuous exchange with colleagues, researchers, physiotherapists and neurologists, it was possible to develop the application model, to define a protocol for the rebalancing of coordination between vision and other perceptual processes and to develop a special device, patented in Italy, Europe and the United States, which improves quality of life and optimizes the work of professionals.