Abstract: A heater device includes an insulating base material, a heater wire, a temperature detection element, a line and a branch line. The heater wire is provided on the insulating base material, forms a path through which current flows when energized, and generates heat when energized. The temperature detection element is provided on the insulating base material and has an electrical characteristics that change according to temperature. The line is provided on the insulating base material and is electrically connected to the temperature detection element. The branch line is provided on the insulating base material, has one end connected to the heater wire and the other end not connected to the heater wire, and extends around the temperature detection element.

Abstract: A heating wire having a first heating wire and a second heating wire. A receiving electrode is provided between the first heating wire and the second heating wire. A transmitting electrode includes a first transmitting electrode provided between the first heating wire and the receiving electrode, and a second transmitting electrode provided between the second heating wire and the receiving electrode. A distance between the first heating wire and the first transmitting electrode is defined as Dh1, a distance between the first transmitting electrode and the receiving electrode is defined as Ds1, a distance between the second heating wire and the second transmitting electrode is defined as Dh2, and a distance between the second transmitting electrode and the receiving electrode is defined as Ds2. A relationship of Dh1?Ds1 and Dh2?Ds2 is satisfied.

Abstract: A heater device includes a heat generating portion formed so as to be adjacent to one surface of an insulating substrate and configured to generate heat, and a heat equalizing portion arranged between adjacent heat generating portions and configured to diffuse the heat of the heat generating portion. The heat generating portion has a linear shape, and at least one of a distance between one of the adjacent heat generating portions and the heat equalizing portion and a distance between the other of the adjacent heat generating portions and the heat equalizing portion is equal to or less than a line width of the heat generating portion. In the heat equalizing portion, a distance between one end of one of the adjacent heat generating portions and the other end of the other of the adjacent heat generating portions is longer than the line width of the heat generating portion.