Abstract: An exercise device for prophylaxis and improving eye acuity conditions that can be used at home or at work without any medical supervision. The device includes several visual targets, a control unit and a keyboard. The device causing one target at a time in a random order to display one of a number of predetermined characters randomly chosen. A person who use the device put equally spaced targets in front of himself or herself at a distance from 0.5' to 20' and adjust the characters displayed to minimal discernable size. During every therapy session the person must denote each character on each target through the keyboard. If the person's response is correct the next character will appear. The amount of correct responses in a session and time intervals between sessions are predetermined depending on the person's age, type of his or her activities and eye acuity conditions.