Patent attributes
An ignition apparatus for an internal combustion engine is small in size and has high reliability capable of withstanding or enduring a vibration environment of a vehicle to which the ignition apparatus is installed. The ignition apparatus includes a spark plug that has its tip end portion presented in the interior of a cylinder of an internal combustion engine main body, a high voltage generation power supply that serves to apply a high voltage to the spark plug, a microwave oscillation device that has an amplifying element for generating a microwave, and a microwave antenna that is mounted on the spark plug, irradiates the micro wave generated from the microwave oscillation device to the interior of the cylinder, thereby forming a plasma generation region around discharge electrodes of the spark plug. The microwave oscillation device is made into a solid state.