US Patent 7727156 Dual frequency band ultrasound transducer arrays

Ultrasound probes that transmits/receives ultrasound pulses with frequencies both in a low frequency (LF) and a high frequency (HF) band, where the radiation surfaces of said HF and LF bands at least have a common region. Several solutions for transmission (and reception) of LF and HF pulses through the same radiation surface are given. The arrays and elements can be of a general type, for example linear phased or switched arrays, or annular arrays or elements with division in both azimuth and elevation direction, like a 1.5D, a 1.75D and a full 2D array. The LF and HF element division and array apertures can also be different.