Woo Seong Tak, Shin Dong Ho, Lim Hyung-Gyu, Seong Ki-Woong, Gottlieb Peter, Puria Sunil, Lee Kyu-Yup, Cho Jin-Ho
Graduate School of Electronic Engineering, Kyungpook National University, 80 Daehak-ro, Buk-gu, 41566 Daegu, Korea.
Department of Biomedical Engineering, Kyungpook National University Hospital, 130 Dongdeok-ro, Jung-gu, 41944 Daegu, Korea.
Sensors (Basel). 2015 Sep 9;15(9):22798-810. doi: 10.3390/s150922798.
Fully implantable hearing devices (FIHDs) have been developed as a new technology to overcome the disadvantages of conventional acoustic hearing aids. The implantable microphones currently used in FIHDs, however, have difficulty achieving high sensitivity to environmental sounds, low sensitivity to body noise, and ease of implantation. In general, implantable microphones may be placed under the skin in the temporal bone region of the skull. In this situation, body noise picked up during mastication and touching can be significant, and the layer of skin and hair can both attenuate and distort sounds. The new approach presently proposed is a microphone implanted at the tympanic membrane. This method increases the microphone's sensitivity by utilizing the pinna's directionally dependent sound collection capabilities and the natural resonances of the ear canal. The sensitivity and insertion loss of this microphone were measured in human cadaveric specimens in the 0.1 to 16 kHz frequency range. In addition, the maximum stable gain due to feedback between the trans-tympanic microphone and a round-window-drive transducer, was measured. The results confirmed in situ high-performance capabilities of the proposed trans-tympanic microphone.
完全植入式听力设备（FIHDs）作为一种新技术被开发出来，以克服传统声学助听器的缺点。然而，目前FIHDs中使用的植入式麦克风在实现对环境声音的高灵敏度、对身体噪音的低灵敏度以及易于植入方面存在困难。一般来说，植入式麦克风可置于颅骨颞骨区域的皮下。在这种情况下，咀嚼和触摸时拾取的身体噪音可能很大，而且皮肤和毛发层都会使声音衰减和失真。目前提出的新方法是将麦克风植入鼓膜。这种方法通过利用耳廓的方向依赖性声音收集能力和耳道的自然共振来提高麦克风的灵敏度。在0.1至16kHz频率范围内，在人体尸体标本中测量了这种麦克风的灵敏度和插入损耗。此外，还测量了经鼓膜麦克风与圆窗驱动换能器之间反馈产生的最大稳定增益。结果证实了所提出的经鼓膜麦克风在原位的高性能。
