Visual system for the blind. Blind man using the TVSS (Tactile Vision Substitution System). The display at right, when compared to the background at left, gives an idea of what can be sensed with this system. TVSS was first developed by Professor Paul Bach-Y-Rita in 1972, and modern versions have since been designed. Input from a video camera (on the side of the head) is converted into output to a vibro-tactile pad on the back (as here), or to an electro-tactile pad on the tongue. The pad is pixellated and vibrates, allowing the blind person to see by 'touch at a distance', as seen here. A key part of this technology is the brain's ability to learn to interpret new sensations.