Thermo-optical sound generator for e.g. earphone, has porous material with pores filled with fluid staying in direct contact with medium and under static pressure, where membrane does not exist between fluid in region of material and medium

摘要

The generator has a porous or fibrous material (8) converting light (3a) into sound in a region of the material, and comprising pores or fiber spaces filled with fluid, where the material is completely or partially open porous and elastic or inelastic. An optical fiber (6) transports light to a light emitting area (7). The fluid stays in direct contact with a surrounding medium and under a static pressure, where a membrane does not exist between the fluid in an inner region of the material and the surrounding medium.