Vibration plate of a speaker and method for producing same.

摘要

A diamond vibration plate of a speaker which has high sound velocity or E/ rho would be superior in high-pitched tone performance. However, diamond vibration plates which are made overall from crystalline diamond were apt to split or break at a flange due to the high rigidity. The periphery of the flange is circularly cut by laser beams to eliminate rugged circumference. The laser treatment converts the crystalline diamond of the flange into non-diamond carbon. The vibration plate with a central spherical part of crystalline diamond and a periphery of a flange of non-diamond carbon excels both in high frequency property and mechanical strength.