| 摘要 |
PURPOSE:To simplify the test for the electrode measurement in the etching process and then obtain a filter element having the good characteristics, by disposing the symbol and the electrode measurement detecting pattern of the comb-line part to the supporting part where both the input and output electrodes are supported. CONSTITUTION:Both comb-line input electrode 12 plus comb-line output electrode 14 which are intermeshing each other are formed on the surface of piezoelectric substrate 11 made of the ceramics or the like. In addition, sound absorbing agent layer 15 is formed along part of electrodes 12 and 14 each. Thus the surface wave filter element is formed. Parts A and B are provided to support electrodes 12b and 14b of such constitution, and then detecting pattern 19 to detect space 18 of the comb-line part plus symbol 20 indicating the article name or the like are provided to parts A and B. The electrode measurement is written to aperture parts 19a-19d of pattern 19 in order to secure the simple test for the measurement when the optimum etching is given to space 18. Thus the manufacture is facilitated for the filter element. |
