| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a diaphragm capable of reducing the lowest resonance frequency and suppressing propping of an edge portion, and a speaker unit and a portable information terminal which are equipped with the diaphragm. <P>SOLUTION: An edge portion 12c comprises a center portion 120, one end portion 121 positioned between the center portion 120 and a voice coil installing portion 12b, and the other end portion 122 positioned between the center portion 120 and a frame installing portion 12d. In a cross-sectional view in a diametrical direction D1 of a diaphragm 12, each of the center portion 120, the one end portion 121 and the other end portion 122 is made from a respective arc forming a convex shape toward the outside of a projecting shape of the edge portion 12c. A curvature radius R0 of the arc of the center portion 120 is larger than the curvature radii R1 and R2 of the one end portion 121 and the other end portion 122, respectively. <P>COPYRIGHT: (C)2012,JPO&INPIT |
