Air conditioner and indoor humidity control method

An air conditioner having a regular mode and a sleep mode, the air conditioner comprising:

• a humidity adjustment unit being configured to humidify or dehumidify air and to supply the air into a room;
• a command receive unit being configured to receive operation initiation commands for the regular mode or the sleep mode;
• and
• a humidity control unit controlling the humidity adjustment unit so that the indoor humidity reaches a first target humidity when the command receive unit has received a command to initiate the regular mode operation, and controlling the humidity adjustment unit so that the indoor humidity reaches a second target humidity being higher than the first target humidity when a predetermined time period has passed after the command receive unit has received a command to initiate the sleep mode operation.

A humidity control method for controlling indoor humidity so that the indoor humidity during a regular mode reaches a first target humidity, the humidity control method comprising:

• receiving a command to initiate a sleep mode operation;
• dehumidifying or humidifying air and supplying the air into a room so that the indoor humidity reaches a second target humidity being lower than the first target humidity;
• and
• humidifying air and supplying the air into the room so that the indoor humidity reaches a third target humidity being higher than the first target humidity, when a predetermined time period has passed after the operation initiation command was received.