| 摘要 |
PROBLEM TO BE SOLVED: To reduce noise by reducing the number of rotations of a fan when a user feels uncomfortable about the noise of the fan but the number of rotations of the fan is kept when the user does not feel uncomfortable about it.SOLUTION: An image display device 100 comprises: a speaker 10 for outputting sound; a display part 14 for displaying an image; a light source 13 for radiating light for displaying an image on the display part 14; a fan 12 for cooling the light source 13; a sound processing part (a calculation part) 9 for calculating information representing clearness of the sound from the ratio or the difference of the sound volume level output from the speaker 10 and the volume level of the noise of the fan; and a CPU (a control part) 8 for controlling the number of rotations of the fan 12 on the basis of the information representing the clearness of the sound calculated by the sound processing part 9. |
