Development of Sound Source Inquiry Equipment: The Sound-Visualizing Camera

Recently, the noise problems of electric power facilities such as noises of transformers, fans, or corona noises of insulators are increasing. When the noises exceed the regulation level on the boundary of site or cause bad influence on in-house workers, effective measures should be taken against noises to solve them. When considering the measures against noises, the sound source and loudness of the noises should be specified. But the accurate evaluation of the target sound by using sound level meter is difficult, because the sound which reaches the noise meter is the sound which contains unrelated sound except for the target. So authors have developed the sound-visualizing camera that can investigate the direction of sound with each frequency every 1Hz. In this paper, authors explain the principle and experimental results of the sound-visualizing camera and its application to various fields.