| 摘要 |
PURPOSE:To secure a necessary length of an output electrode even if a short piezoelectric substrate is used, by using a surface acoustic wave guide path including at least >=1 curve part to form an output electrode which extracts a convolution signal. CONSTITUTION:A substrate 1 is made of a material like LiNbO3, etc. having a large performance exponent M that shows the intensity of a nonlinear interaction. Then roller-screen type converters 2 and 3 which convert an electric signal into a surface acoustic wave are formed on the surface of the substrate 1, and at the same time beam compressors 4 and 5 are provided on an extending line in the propagating direction of the surface acoustic wave to decrease the beam width of the surface acoustic wave. Then two surface acoustic waves signals passed through the compressors 4 and 5 are made incident to a U-shaped convolution signal extracting electrode 6 through end surfaces opposite to each other. Thus a convolution signal having carrier angle frequency 2omega is obtained. In this case, an earth electrode 7 is provided along the electrode 6 to secure a reference potential. |
