Optoelectronic circuitry for a reading aid

A reading aid for the blind has been constructed that generates a tactile image of ordinary printing by using a rectangular array of vibratory pins. Reading material is focused on an array of phototransistors. These individually gate ON or OFF corresponding vibratory piezoelectric reeds that present the tactile image. A first model is described that verifies the unambiguous readability of typed material, but at a slow rate. It demonstrates as well the practicability of implementation of the reading aid using silicon phototransistors and integrated circuits.