The Optacon is an electromechanical device which can enable blind or deafblind people to read printed material that isn't transcribed into Braille. This compact reading aid is highly portable, with the main electronics unit being around the size of a tape recorder. This is connected by a thin cable to a camera model which is around the size of a penknife. The electronics unit comes with a refreshable 'tactile array' which the blind user places their index finger on. The user then moves the camera module along a line of print and scans an image of the text which is then transmitted through the connecting cable back to the main electronics unit. The tactile array in the unit has a matrix of tiny rods, these can expand by using something known as the piezo effect. This means rods will expand when a voltage is applied to them. The rods are vibrated which will correspond to black parts of the image. In this way a tactile image of the letter being viewed by the camera module is created.As the lens module is moved along the print line by the user, tactile images of print letters can be felt moving across the array of rods located under the user's finger. The rate at which the rods vibrate can also be customised via a knob which can adjust the intensity. Similarly the the image threshold and which images will be interpreted as dark or light print on a background can also be adjusted.
To use the Optacon successfully the user must have a decent grasp of the English language. This is due to the fact that speed and ease of reading depends upon a users ability to anticipate words which occur commonly like, "the", "and" or "of". This machine is a great option for those who have lost both hearing and sight after acquiring knowledge of the English language. However for those who are congenitally deafblind it would be almost impossible to use as it relies on the ability to anticipate certain words.