Device for detecting acoustic waves

Abstract

A device for detecting acoustic waves may include a housing having a housing wall with an inner surface, and an acoustic wave sensor provided at least partially inside the housing and configured to detect acoustic waves. The inner surface of the housing wall is made in at least half of its entire area of a thermally insulating material.

What is claimed is: 
     
         1 . A device for detecting acoustic waves, comprising:
 a housing having a housing wall with an inner surface; and   an acoustic wave sensor provided at least partially inside the housing and configured to detect acoustic waves,   wherein the inner surface of the housing wall is made in at least half of its entire area of a thermally insulating material.   
     
     
         2 . The device of  claim 1 , wherein the thermal conductivity of the thermally insulating material is less than 20 W/(m·K). 
     
     
         3 . The device of  claim 1 ,
 wherein the inner surface of the housing wall is made in at least 70% of its entire area of the thermally insulating material.   
     
     
         4 . The device of  claim 1 ,
 wherein the housing wall comprises a layered portion comprising a plurality of layers stacked in a thickness direction of the housing wall;   wherein the layered portion comprises an inner layer forming at least a part of the inner surface of the housing wall, and at least one outer layer positioned closer to an outer surface of the housing wall than the inner layer.   
     
     
         5 . The device of  claim 4 ,
 wherein the inner layer is made at least in part of the thermally insulating material.   
     
     
         6 . The device of  claim 5 ,
 wherein at least one outer layer is made at least in part of a material having a higher thermal conductivity than the material of the inner layer;   wherein optionally one outer layer forming at least a part of the outer surface of the housing wall has a higher thermal conductivity than the inner layer.   
     
     
         7 . The device of  claim 6 ,
 wherein at least one outer layer is made at least in part of a metal.   
     
     
         8 . The device of  claim 4 ,
 wherein the inner layer is made at least in part of a material which is optically transparent.   
     
     
         9 . The device of  claim 8 ,
 wherein the optically transparent material is optically transparent in at least one of the following frequency ranges:
 the infrared frequency range; 
 the visible frequency range; 
 the ultraviolet frequency range. 
   
     
     
         10 . The device of  claim 9 ,
 wherein the optically transparent material has a transmittance of at least 80% in at least one of the following frequency ranges:
 the infrared frequency range; 
 the visible frequency range; 
 the ultraviolet frequency range. 
   
     
     
         11 . The device of  claim 4 ,
 wherein at least one outer layer is made at least in part of a material which is optically opaque.   
     
     
         12 . The device of  claim 11 ,
 wherein the optically opaque material is optically opaque in at least one of the following frequency ranges:
 the infrared frequency range; 
 the visible frequency range; 
 the ultraviolet frequency range. 
   
     
     
         13 . The device of  claim 12 ,
 wherein the optically opaque material has a reflectance of at least 80% in at least one of the following frequency ranges:
 the infrared frequency range; 
 the visible frequency range; 
 the ultraviolet frequency range. 
   
     
     
         14 . The device of  claim 1 ,
 wherein the housing comprises a substrate on which the acoustic wave sensor is mounted, and a lid.   
     
     
         15 . The device of  claim 14 ,
 wherein the lid comprises a layered portion.   
     
     
         16 . The device of  claim 14 ,
 wherein at least a part of the substrate facing to the inside of the housing is coated with a thermally insulating substrate material.   
     
     
         17 . The device of  claim 16 ,
 wherein the thermal conductivity of the thermally insulating substrate material is less than 20 W/(m·K).   
     
     
         18 . The device of  claim 14 ,
 wherein the substrate comprises an electronic circuit mounted thereon inside the housing,   wherein the electronic circuit is at least in part coated with the thermally insulating substrate material.   
     
     
         19 . The device of  claim 1 ,
 wherein the acoustic wave sensor is configured as a microphone.   
     
     
         20 . The device of  claim 1 ,
 wherein the housing wall comprises an optically transparent window portion providing an optical port to the inside of the housing.   
     
     
         21 . The device of  claim 1 ,
 wherein at least one of the thermally insulating material or the thermally insulating substrate material is selected from glass materials, plastic materials, and oxides.   
     
     
         22 . The device of  claim 4 ,
 wherein the housing wall comprises a portion extending from the inner surface to the outer surface of the housing wall, the portion being entirely made of the thermally insulating material.   
     
     
         23 . A device for detecting acoustic waves, comprising:
 a housing having a metal housing portion; and   a layer formed on an inner surface of the metal housing portion;   an acoustic wave sensor provided at least partially inside the housing and configured to detect acoustic waves,   wherein the layer is made of a material having a thermal conductivity that is smaller than the thermal conductivity of the metal housing portion.   
     
     
         24 . A device for detecting acoustic waves, comprising:
 a housing having a housing wall with an inner surface and an outer surface; and   an acoustic wave sensor provided at least partially inside the housing and configured to detect acoustic waves,   wherein the housing wall comprises a portion extending from the inner surface to the outer surface of the housing wall, the portion being entirely made of a thermally insulating material.   
     
     
         25 . The device of  claim 24 ,
 wherein the thermal conductivity of the thermally insulating material is less than 20 W/(m·K).