Multi-layer coating for optoacoustic probe

Abstract

Disclosed is an optoacoustic probe with a coated transducer assembly. The probe includes a transducer assembly with a multi-layer coating on the active end thereof. The multi-layer coating includes a layer of parylene and at least two layers of metal. In an embodiment, the multi-layer coating includes a layer of nickel, at least one layer of parylene, and a layer of gold.

What is claimed is: 
     
         1 . An optoacoustic probe with a coated transducer assembly, the probe comprising:
 a transducer assembly having an active end, the transducer assembly comprising a plurality of transducer elements;   a multi-layer coating on the active end of the transducer assembly, the multi-layer coating comprising at least one layer of parylene, and at least two layers of metal; and   a housing having a distal end and housing the transducer assembly and a plurality of other components, at least one of the housing and one or more of the plurality of other components securing the transducer assembly such that the active end of the transducer assembly is at the distal end of the housing.   
     
     
         2 . The optoacoustic probe claimed in  claim 1 , wherein the multi-layer coating on the active end of the transducer assembly comprises:
 a layer of nickel, the layer of nickel being one of the at least two layers of metal; and   a first layer of parylene, the first layer of parylene being one of the at least one layer of parylene; and   a layer of gold, the layer of gold being one of the at least two layers of metal.   
     
     
         3 . The optoacoustic probe claimed in  claim 2 , wherein the multi-layer coating on the active end of the transducer assembly further comprises:
 a second layer of parylene, the second layer of parylene being another one of the at least one layer of parylene.   
     
     
         4 . The optoacoustic probe claimed in  claim 2 , wherein the first layer of parylene is over the layer of nickel. 
     
     
         5 . The optoacoustic probe claimed in  claim 4 , wherein the layer of gold is over the first layer of parylene. 
     
     
         6 . The optoacoustic probe claimed in  claim 5 , wherein the wherein the multi-layer coating on the active end of the transducer assembly further comprises:
 a second layer of parylene, the second layer of parylene being another one of the at least one layer of parylene.   
     
     
         7 . The optoacoustic probe claimed in  claim 5 , wherein at least a portion of the multi-layer coating is mechanically secured by at least one of the housing and one or more of the plurality of other components to prevent curling or peeling. 
     
     
         8 . A multi-layer coating for an acoustically coupling portion of an optoacoustic probe, the multi-layer coating comprising a layer of nickel, at least one layer of parylene, and a layer of gold. 
     
     
         9 . The multi-layer coating claimed in  claim 8 , wherein the at least one layer of parylene, the layer of nickel and the layer of gold of the multi-layer coating are coated in the order: the layer of nickel, one of the at least one layer of parylene and the layer of gold. 
     
     
         10 . The multi-layer coating claimed in  claim 9 , wherein the layer of nickel, the one of the at least one layer of parylene, and the layer of gold are adjacent to one-another. 
     
     
         11 . The multi-layer coating claimed in  claim 9 , wherein
 a transducer assembly having an outer surface forms at least a portion of the acoustically coupling portion of the handheld probe,   the outer surface of the transducer assembly comprises RTV silicon rubber; and   the one of the at least one layer of parylene is adjacent to the outer surface of the transducer assembly.   
     
     
         12 . The multi-layer coating claimed in  claim 11 , wherein the RTV silicon rubber is doped with TiO 2 . 
     
     
         13 . The multi-layer coating claimed in  claim 11 , wherein the RTV silicon rubber is doped with approximately 4% TiO 2 . 
     
     
         14 . The multi-layer coating claimed in  claim 8 , wherein the layer of nickel, the at least one layer of parylene, and the layer of gold of the multi-layer coating are coated in the order: the layer of nickel, one of the at least one layer of parylene, the layer of gold and one more layer of the at least one layer of parylene. 
     
     
         15 . The multi-layer coating claimed in  claim 14 , wherein the layer of nickel, one of the at least one layer of parylene, the layer of gold and one more layer of the at least one layer of parylene are adjacent to one-another. 
     
     
         16 . The multi-layer coating claimed in  claim 14 , wherein
 a transducer assembly having an outer surface forms at least a portion of the acoustically coupling portion of the handheld probe,   the outer surface of the transducer assembly comprises RTV silicon rubber; and   the one of the at least one layer of parylene is adjacent to the outer surface of the transducer assembly.   
     
     
         17 . The multi-layer coating claimed in  claim 16 , wherein the RTV silicon rubber is doped with TiO 2 . 
     
     
         18 . The multi-layer coating claimed in  claim 16 , wherein the RTV silicon rubber is doped with approximately 4% TiO 2 . 
     
     
         19 . A method of providing a durable gold coating to an RTV silicon rubber acoustic lens, the method comprising the steps of:
 coating the acoustic lens with a first continuous layer;   coating the first continuous layer with a second continuous layer; and   coating the second continuous layer with a layer of gold;   wherein the first continuous layer is selected from the group consisting of: parylene and nickel.   
     
     
         20 . The method of  claim 19 , wherein the first continuous layer is nickel and the second continuous layer is parylene. 
     
     
         21 . The method of  claim 19 , further comprising the step of coating the layer of gold with an outer layer of parylene. 
     
     
         22 . The method of  claim 21 , wherein the first continuous layer is nickel and the second continuous layer is parylene.