Abstract: A sensor having a movable element, such as a microphone with a diaphragm, where received sound is filtered by two parallel acoustical filters before being sensed by the sensor, where one acoustical filter has a larger acoustical resistance and a lower acoustical mass than the other.

Abstract: The present invention relates to a microphone that includes a housing and a diaphragm and backplate located with the housing. The housing has a sound port for receiving the sound. The diaphragm undergoes movement relative to the backplate, which it opposes, in response to the incoming sound. The backplate has a charged layer with a first surface that is exposed to the diaphragm and a second surface opposite the first surface. The backplate further includes a conductor for transmitting a signal from the backplate to electronics in the housing. The conductor faces the second surface of the charged layer. To minimize the charge degradation created by contact with or infiltration of foreign materials, the first surface, the second surface, or both surfaces of the charged layer includes a protective layer thereon.

Abstract: The present invention relates to a microphone that includes a housing and a diaphragm and backplate located with the housing. The housing has a sound port for receiving the sound. The diaphragm undergoes movement relative to the backplate, which it opposes, in response to the incoming sound. The backplate has a charged layer with a first surface that is exposed to the diaphragm and a second surface opposite the first surface. The backplate further includes a conductor for transmitting a signal from the backplate to electronics in the housing. The conductor faces the second surface of the charged layer. To minimize the charge degradation created by contact with or infiltration of foreign materials, the first surface, the second surface, or both surfaces of the charged layer includes a protective layer thereon.

Abstract: The present invention relates to a microphone that includes a housing and a diaphragm and backplate located with the housing. The housing has a sound port for receiving the sound. The diaphragm undergoes movement relative to the backplate, which it opposes, in response to the incoming sound. The backplate has a charged layer with a first surface that is exposed to the diaphragm and a second surface opposite the first surface. The backplate further includes a conductor for transmitting a signal from the backplate to electronics in the housing. The conductor faces the second surface of the charged layer. To minimize the charge degradation created by contact with or infiltration of foreign materials, the first surface, the second surface, or both surfaces of the charged layer includes a protective layer thereon.

Abstract: The present invention relates to a microphone that includes a housing and a diaphragm and backplate located with the housing. The housing has a sound port for receiving the sound. The diaphragm undergoes movement relative to the backplate, which it opposes, in response to the incoming sound. The backplate has a charged layer with a first surface that is exposed to the diaphragm and a second surface opposite the first surface. The backplate further includes a conductor for transmitting a signal from the backplate to electronics in the housing. The conductor faces the second surface of the charged layer. To minimize the charge degradation created by contact with or infiltration of foreign materials, the first surface, the second surface, or both surfaces of the charged layer includes a protective layer thereon.

Abstract: The present invention relates to a microphone that includes a housing and a diaphragm and backplate located with the housing. The housing has a sound port for receiving the sound. The diaphragm undergoes movement relative to the backplate, which it opposes, in response to the incoming sound. The backplate has a charged layer with a first surface that is exposed to the diaphragm and a second surface opposite the first surface. The backplate further includes a conductor for transmitting a signal from the backplate to electronics in the housing. The conductor faces the second surface of the charged layer. To minimize the charge degradation created by contact with or infiltration of foreign materials, the first surface, the second surface, or both surfaces of the charged layer includes a protective layer thereon.

Abstract: A microphone is constructed to be more tolerant to a wide range of relative humidity conditions without adversely affecting the performance of the microphone. The microphone includes a housing with a sound port for receiving sound and an electret assembly for converting the sound into an output signal. The electret assembly includes a diaphragm and a backplate. The backplate is made of at least two layers, usually polymeric layers. The first layer of material has a first hygroscopic coefficient and a second layer of material has a second hygroscopic coefficient. The first and second layers cause the backplate to bend in response to higher humidity conditions, thereby minimizing the adverse effects on microphone performance caused by characteristic changes in the diaphragm at the higher humidity conditions.

Abstract: The present invention relates to a microphone that includes a housing and a diaphragm and backplate located with the housing. The housing has a sound port for receiving the sound. The diaphragm undergoes movement relative to the backplate, which it opposes, in response to the incoming sound. The backplate has a charged layer with a first surface that is exposed to the diaphragm and a second surface opposite the first surface. The backplate further includes a conductor for transmitting a signal from the backplate to electronics in the housing. The conductor faces the second surface of the charged layer. To minimize the charge degradation created by contact with or infiltration of foreign materials, the first surface, the second surface, or both surfaces of the charged layer includes a protective layer thereon.

Abstract: A microphone is constructed to be more tolerant to a wide range of relative humidity conditions without adversely affecting the performance of the microphone. The microphone includes a housing with a sound port for receiving sound and an electret assembly for converting the sound into an output signal. The electret assembly includes a diaphragm and a backplate. The backplate is made of at least two layers, usually polymeric layers. The first layer of material has a first hygroscopic coefficient and a second layer of material has a second hygroscopic coefficient. The first and second layers cause the backplate to bend in response to higher humidity conditions, thereby minimizing the adverse effects on microphone performance caused by characteristic changes in the diaphragm at the higher humidity conditions.