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1.助听器发展简介为了帮助耳聋患者利用残余听力,提高对正常的语言声的接收效果而设计的助听器,已有八十年的历史。但是,早期的助听器对声音的放大作用很有限(约20分贝),噪声也较大,因此实用价值不大。随着半导体技术的发展,四十年代出现了利用晶体管放大电路和小型电声器件组装的、可以放在衣服口袋里的盒式助听器。虽然性能还不够理想,但是对于一般传导型耳聋来说,已具有相当明显的助听效果了。
1. Introduction to the development of hearing aids Hearing aids designed to help deaf patients utilize residual hearing and improve their reception of normal speech have been around for eighty years. However, the early hearing aids had a limited effect on the sound amplification (about 20 dB) and the noise was large, so they were of little practical value. With the development of semiconductor technology, there appeared a box-type hearing aid that can be placed in a pocket of clothes in the 1940s by using a transistor amplifier and a small electroacoustic device. Although the performance is not ideal, but for general conduction deafness, has a very significant hearing aid effect.