Development of a miniature second-order directional microphone diaphragm for hear

描述（由申请人提供）：拟议研究的主要目的是开发一种用于助听器的微型麦克风振膜，该振膜在对语音重要的频率范围内对声音实现二阶方向灵敏度。能够实现二阶方向灵敏度的助听器能够对干扰语音的不想要的声音衰减超过9dB。现有的实现这种降噪的方法是基于对来自三个非定向麦克风的信号的处理。这些系统的有效性受到麦克风自噪声的影响以及对麦克风之间失配的敏感性的阻碍。此外，容纳三个麦克风所需的空间限制了这些设备在较大的耳后式助听器中的应用。所提出的研究的方法避免了这些困难，通过开发一个单一的微型麦克风膜片，有可能实现二阶方向响应超过大部分的可听频率范围。微型麦克风振膜将被设计和制造，包括我们在目前的NIH BRP奖下开发的成功的一阶定向麦克风振膜的延伸。将对设计进行优化，以确保二阶方向响应在尽可能宽的频率范围内占主导地位。设计将使用硅微加工技术制造，定向声学响应将通过实验验证。通过比较二阶响应与响应的二阶导数的测量值来完成制造的振膜的声学表征，所述响应的二阶导数的测量值使用在振膜附近的位置阵列处的声压的测量值获得。这项工作将证明创建一个微型二阶麦克风膜片，可以纳入助听器的可行性。在展示了一个实用的麦克风膜片设计，电子读出将在后续的研究开发，以将膜片运动转换成电子信号。 公共卫生相关性：据估计，全世界有5亿人患有听力损失，使其成为世界上头号残疾（Phonak，2006年9月）。助听器仍然是治疗的主要形式，但用户的头号投诉是在嘈杂的环境中难以理解语音。由于设计，耻辱和成本问题，大约一半的人可以从助听器中受益而不使用它们;然而，较小的助听器是他们的第二首选解决方案。这项拟议的研究将导致微型二阶定向麦克风技术的显着改进，这将有助于用户在复杂的声学环境中进行通信，并吸引新用户。

DESCRIPTION (provided by applicant): The primary aim of the proposed research is to develop a miniature microphone diaphragm for hearing aids that achieves second-order directional sensitivity to sound over the frequency range that is important for speech. A hearing aid that can achieve second-order directional sensitivity can be capable of over 9 dB of attenuation of unwanted sounds that interfere with speech. Existing approaches to achieving this noise reduction are based on the processing of signals from three nondirectional microphones. The effectiveness of these systems has been hampered by the effects of microphone self-noise, and sensitivity to mismatches between the microphones. In addition, the space required to house the three microphones limits the application of these devices to larger behind-the-ear hearing aids. The approach of the proposed study avoids these difficulties by developing a single miniature microphone diaphragm that has the potential of achieving second-order directional response over much of the audible range of frequencies. Miniature microphone diaphragms will be designed and fabricated that comprises an extension of the successful first-order directional microphone diaphragms we have developed under our current NIH BRP award. The designs will be optimized to ensure that the 2nd order directional response dominates over as wide a range of frequencies as possible. The designs will be fabricated using silicon microfabrication technology and the directional acoustic response will be verified experimentally. The acoustic characterization of the fabricated diaphragms will be accomplished by comparing the 2nd order response with measurements of the 2nd derivative of the response obtained using measurements of the sound pressure at an array of locations in the vicinity of the diaphragm. This effort will demonstrate the feasibility of creating a miniature 2nd order microphone diaphragm that can be incorporated into hearing aids. Having demonstrated a practical microphone diaphragm design, an electronic read-out will be developed in a follow-on study to transduce the diaphragm motion into an electronic signal. PUBLIC HEALTH RELEVANCE: An estimated 500 million people worldwide suffer hearing loss, making it the number one disability in the world (Phonak, Sep 2006.) Hearing aids remain the primary form of treatment, yet the number one complaint of users is difficulty understanding speech in noisy environments. About half of those who could benefit from an aid do not use them because of design, stigma and cost issues; however a smaller hearing aid is their second most preferred solution. This proposed research will lead to a dramatic improvement in miniature, second-order directional microphone technology that will help users communicate in complex acoustical environments and attract new users.