Abstract: Disclosed is an air cleaner capable of removing contaminants in the air by using various air cleaning methods. The air cleaner includes a case including an upper opening through which air is introduced, a lower opening through which purified air is discharged, a filter module detachably mounted in the case and configured to filter out contaminants in the air, an injector injecting water, and an electric dust collecting device located below the injector and collecting dust in the air.

Abstract: Disclosed is an air cleaner capable of removing contaminants in the air by using various air cleaning methods.

Abstract: A robot cleaner is provided that includes a driver configured to move the robot cleaner, and a suction unit configured to suck foreign objects from a surface below the robot cleaner. The robot cleaner also includes a detector configured to capture images of regions disposed in front of the robot cleaner. The robot cleaner further includes a controller configured to control the detector to capture a first image of a region before cleaning, control the detector to capture a second image of the region after cleaning, and generate cleaning result information using the first and second images.

Abstract: An apparatus including a first speaker configured to output higher-frequency sound from among sound of a channel via at least one slit, and a second speaker configured to output lower-frequency sound from among the sound of the channel via at least one other slit. The at least one slit may have a thickness that is less than a wavelength of sound emitted.

Abstract: A robot cleaner is provided that includes a driver configured to move the robot cleaner, and a suction unit configured to suck foreign objects from a surface below the robot cleaner. The robot cleaner also includes a detector configured to capture images of regions disposed in front of the robot cleaner. The robot cleaner further includes a controller configured to control the detector to capture a first image of a region before cleaning, control the detector to capture a second image of the region after cleaning, and generate cleaning result information using the first and second images.

Abstract: An apparatus including a first speaker configured to output higher-frequency sound from among sound of a channel via at least one slit, and a second speaker configured to output lower-frequency sound from among the sound of the channel via at least one other slit. The at least one slit may have a thickness that is less than a wavelength of sound emitted.