Control method of dishwasher

A method of controlling a dishwasher, wherein the dishwasher includes a tub that defines a washing chamber in which one or more washing targets are accommodated, at least one spray nozzle that is rotatably provided in the washing chamber and that is configured to spray washing water to the washing chamber, a rack that is accommodated in the washing chamber and that is configured to receive the one or more washing targets, and a microphone provided in the tub, the method comprising:

• spraying, by the at least one spray nozzle, the washing water while the at least one spray nozzle is rotating;
• analyzing a characteristic of a sound wave input to the microphone, the sound wave being generated based on the washing water colliding with the one or more washing targets;
• determining whether a washing target made of a set material is present among the one or more washing targets based on the analyzed characteristic of the sound wave;
• determining, based on determining that the washing target made of the set material is present, a location in which the washing target made of the set material is present according to the analyzed characteristic of the sound wave;
• and
• reducing an amount of impact applied to the washing target made of the set material by the washing water sprayed from the at least one spray nozzle,
• wherein analyzing the characteristic of the sound wave includes analyzing at least one of an amplitude or a frequency of the sound wave input to the microphone.