A transparent sheet display by plastic MEMS

A new type of color-image display pixel based on MEMS ( microelectromechanical systems) technology of plastic materials is presented. The mechanism for making color is optical interference using a Fabry-Perot interferometer. A thin sheet of PEN ( polyethylene naphthalate) with a metal half-mirror was laminated over a glass or PEN substrate with an optical cavity inside. The electrostatically controlled deformation of the PEN film changes the color of the transmitting light by interference within the optical cavity. Color pixels of three primary colors ( red, green, and blue) were successfully developed and demonstrated, with a driving voltage ranging from 80 to 120 V-dc. Thanks to the mechanical flexibility of the PEN films, the display could operate even when placed on a curved surface.