Abstract: A printing head which comprises an insulating substrate and a plurality of printing electrodes for a resistive ribbon type printing apparatus, in which a ribbon composed of a layer of thermal transferable ink and an electrical resistive layer is supplied with an electric current through selected printing electrodes so that the current passes through a portion of the resistive layer to generate Jule heat and melt a portion of the ink layer, and the molten ink is transferred to a paper. The printing electrodes are made of a plating material and the substrate is made of a machinable ceramic having a hardness equal to or lower than the hardness of the printing electrodes.

Abstract: This specification teaches an electrically heated, glass vision unit having a complex curved configuration. The unit is made by cutting a glass substrate (10) from a flat glass bracket (12). The glass substrate (10) has first and second surfaces separated by a uniform distance. A pair of electrically conductive bus bars (16--16) are applied to one of the surfaces of the glass substrate (10). The bus bars (16--16) are so positioned on the flat glass substrate (10) that when the substrate (10) is bent to form the glass vision unit of complex curved configuration, inboard edges (16a--16a) of the pair of electrically conductive bus bars (16--16) are equally distant from one another throughout their entire extent. The flat glass substrate (10) is bent to form the glass vision unit of complex curved configuration. A conductive coating (20) is applied to the one surface of the glass substrate (10) and extends between the pair of bus bars (16--16) throughout their entire extent.