Visual system for the blind. Blind man using the TVSS (Tactile Vision Substitution 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'. A key part of this technology is the brain's ability to learn to interpret new sensations.