US Patent 7745522 Acoustic waveguide plate with nonsolid cores

An acoustic (sound or ultrasound) wave transmitter having a plurality of waveguides is described, and a method of making such a transmitter is described. Each waveguide may have a cladded core. The core may be a liquid such as water, alcohol or mineral oil. Alternatively, the core may be a colloidal gel, such as gelatin dissolved in at least one of water, vinyl plastisol or silicone gel. The cladded core is capable of transmitting acoustic wave energy from a first end surface to a second end surface of the cladded core. The waveguides may be substantially fixed relative to each other by a binder. The binder may be formed by fusing the claddings together, potting a material between the waveguides and/or mechanically holding the waveguides.