An eyeglass frame and electroacoustic device combination for the improvement of natural hearing has temples that contain or carry electronic and electroacoustic devices. To enable persons with reduced hearing to again be able to follow a conversation in noisy surroundings, e.g. to concentrate on a partner...http://www.google.com.hk/patents/US4904078?utm_source=gb-gplus-share專利 US4904078 - Eyeglass frame with electroacoustic device for the enhancement of sound intelligibility
