Piezoelectric Actuator

A device that converts electrical energy into precise mechanical motion using the piezoelectric effect — the property of certain materials to change shape when an electric voltage is applied. In assistive technology, piezoelectric actuators are the dominant mechanism used in refreshable Braille displays to raise and lower individual Braille dots. Each actuator can push a pin up to represent a raised dot or allow it to fall to represent the absence of a dot. The high cost of these actuators, combined with the need for one per Braille dot (six or eight per cell, multiplied by 20-80 cells), is the primary reason refreshable Braille displays remain expensive.