Patent ID: 8841589

Claim:
A ceramic heater that is formed by providing a heater pattern on a ceramic substrate, the heater pattern having a heat generation portion for generating heat when current is passed therethrough and a pair of lead portions for supplying current to the heat generation portion, the ceramic heater being characterized in that: the heat generation portion has a pair of heat generation connecting ends that are connected to the pair of lead portions; the lead portions have respective lead connecting ends that are connected to the respective heat generation connecting ends of the heat generation portion; the heat generation portion and the lead portions are connected to each other in connecting portions in each of which the heat generation connecting end overlaps with the corresponding lead connecting end; when the ceramic substrate is viewed from a direction perpendicular to a surface in which the heater pattern is formed, the heater pattern is in a shape having sides in a width direction of each connecting portion, each side having an intersection portion in which a contour of the heat generation connecting end of the heat generation portion intersects a contour of the lead connecting end of the corresponding lead portion to form a concave portion in which the heater pattern is recessed inward; at least one of the heat generation connecting end of the heat generation portion and the lead connecting end of the lead portion in the shape of the heater pattern has an edge that is an arc-shaped curve.