噪音对人体有害,已经不算什么新闻了,长期在充斥着强噪音的场所生活工作,终日昏头昏脑,思维迟顿,食欲不振,消化系统机能衰退,听觉细胞受到严重伤害,仅美国就有九百万以上公民受它的折磨,十分痛苦,虽然在不太强的噪音下生活时间长了也能适应,但据医生调查,十几岁的青年工作二十五年后听力基本丧失,要与聋子为伍,尤其投身于采矿,造船,食品加工,印刷等行业谋生的人,无不付出双耳作代价。过去曾有人研究出各种防噪音设备,从给机器配橡皮垫到隔音塞不下数十种,然而效果并不佳,甚至飞机驾驶员戴的耳机(里面有一层厚厚的塑料膜吸收声波)也不尽如人意。直到八十年代美国和欧洲几家公司研制出高效能,技术尖端的电子反噪音耳机后,才打开被动局面。新型耳机内有一个微型装置,可以接收噪音,通过一个专用线路加工后向外发出反噪音波,噪音 Noise is harmful to the human body. It is no longer news. It has long been working in a place full of strong noises. It has been fainting for a long time, thinking late, losing appetite, digestive system decline, and hearing cells severely harmed. Only the United States has 900 Tens of thousands of citizens are tortured by it. It is very painful. Although life time can be adjusted under the not too noisy noise, according to the doctor’s investigation, the hearing loss is basically lost to the teenage youth after 25 years of work. In particular, those engaged in the mining, shipbuilding, food processing, printing and other industries to make a living make every effort to pay their ears. In the past, a variety of anti-noise devices have been developed. From dozens of rubber lugs to noise dampers, the effect is not good. Even earphones worn by pilots (with a thick plastic film absorbing sound waves) Not satisfactory. Until the eighties the United States and several European companies developed high-performance, sophisticated electronic anti-noise headphones, it turned on the passive situation. The new headphones have a miniature device that can receive noise, processed through a dedicated line out of the anti-noise waves, noise