The ''plastic retina'': Image enhancement using polymer grid triode arrays

An array of polymer grid triodes (PGTs) connected through a common grid functions as a ''plastic retina'' which provides local contrast gain control for image enhancement. This device, made from layers of conducting polymers, functions as an active resistive network that performs center-surround filtering. The PGT array with common grid is a continuous analog of the discrete approach of Mead, with a variety of fabrication advantages and with a significant saving of ''real estate'' within the unit cell of each pixel.