Patent ID: 7621369

Claim:
A sound projector for generating a sound beam along a radiant axis, the sound projector comprising: a reflector exhibiting symmetry with respect to the radiant axis and having a focal ring of non-zero circumference; an annular sound source of non-zero circumference dimensionally matching the non-zero circumference of the focal ring, the annular sound source being centered on the radiant axis and oriented to radiate sound energy into the reflector for reflection forward along the radiant axis; the annular sound source comprising a plurality of discrete sound sources arranged radially around and oriented into the reflector, the discrete sound sources being mutually spaced to operate as a linear array; the annular sound source being located in a plane perpendicular to the radiant axis; the reflector being a hyperboloid and having a contour along at least a portion of its length resulting in the focal ring lying in a plane perpendicular to the radiant axis; and means for repositioning the annular sound source along the radiant axis and thereby positioning the annular sound source relative to the reflector to produce a dispersive sound field, a non-dispersive sound field when the annular sound source is substantially positioned at the annular focus of the reflector or a sound field having a convergence point forward from the reflector.