A display unit comprising a board (10), a three-primary color-independent optical waveguide (100) arranged and formed on one side thereof, and a transparent electrode (30) and an electrode (40) serving as counter electrodes arranged and formed to sandwich an electric field reaction material (20) formed on one of two optical waveguides constituting the optical waveguide (100) and being transparent to waveguide light, wherein part of the waveguide light is allowed to pass at least the field reaction material (20), and a voltage applied between these counter electrodes changes the shape of the reaction material (20) to scatter the waveguide light and form pixels in to a displayed image, whereby the device is free from a mechanical drive unit, high in reliability, quality, brightness and response speed, low in power consumption and cost, and capable of full color displaying.