| 摘要 |
PURPOSE:To obtain a diaphragm with good sensitivity easily at low cost by removing part of metallic plates by etching work after sticking the metallic plates to both surfaces of the synthetic resin film, and thus forming a frame. CONSTITUTION:The synthetic resin film 11 as a diaphragm is heated about up to its melting point and metallic plates 12a and 12b are stuck to both surfaces of the film 11. Then surfaces of the metallic plates 12a and 12b which are left as the frame are covered with resist layers 13a and 13b. In this state, parts of the metallic plates 12a and 12b which are not masked with the layers 13a and 13b are etched to form frames 12a' and 12b' while the film 11 as the diaphragm 11' is exposed. Then, the layers 13a and 13b are removed and the body is cut in an adequate outward appearance shape. This manufacturing method facilitates the manufacture and reduces the stiffness of the diaphragm, improving the sensitivity and performance of the diaphragm. |
