Patent 7843476 was granted and assigned to Sony on November, 2010 by the United States Patent and Trademark Office.
A thermal head includes a head containing a glass layer. The glass layer has a projecting portion on one surface and a concave groove on the other surface at a position opposed to the projecting portion. The head further contains a heating resistor disposed on the projecting portion, and a pair of electrodes disposed on both sides of the heating resistor. The thermal head further includes a rigid substrate on which a control circuit for the head is provided, and a flexible substrate for electrically connecting the head and the rigid substrate.