MICROWAVE OUTPUT DEVICE AND PLASMA PROCESSING APPARATUS

In a microwave output device of an embodiment, a part of travelling wave propagating from a microwave generation unit to an output are output from a directional coupler. A first measurement unit generates an analog signal corresponding to a power of the part of the travelling wave by using diode detection, and converts the analog signal into a digital value. One or more correction coefficients associated with a set frequency and a set power of a microwave designated for the microwave output device are selected. The selected one or more correction coefficients are multiplied by the digital value, and thus a measured value is determined.