Organic light active devices with particulated light active material in a carrier matrix

Abstract

A light active device includes a semiconductor particulate dispersed within a carrier material. A first contact layer is provided so that on application of an electric field charge carriers having a polarity are injected into the semiconductor particulate through the conductive carrier material. A second contact layer is provided so that on application of the electric field to the second contact layer charge carriers having an opposite polarity are injected into the semiconductor particulate through the conductive carrier material. The semiconductor particulate comprises at least one of an organic and an inorganic semiconductor. The semiconductor particulate may comprise an organic light active particulate that includes at least one conjugated polymer. When an electric field is applied between the first and second contact layers to the semiconductor particulate through the conductive carrier material, the second contact layer becomes positive relative to the first contact layer and charge carriers of opposite polarity are injected into the semiconductor particulate. The opposite polarity charge carriers combine to form in the conjugated polymer charge carrier pairs which decay radiatively so that radiation is emitted from the conjugated polymer. In this case, the inventive light active device acts as a light emitting diode.