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Typical Sensitivity Plots

Typical Directivity Plots (5 MHz)

Durability

Each HNA hydrophone is "stress-tested" to a high-intensity ultrasound field for one hour, verifying that it survives
without any changes either in appearance or in its spectral response between 1 and 20 MHz.
The stress test conditions are provided at the focus of a 1.5 MHz source, operated at 50% duty cycle in deionized,
degassed water at 23C. This provides an exposure intensity of 715 W/cm2 temporal-average and 1430 W/cm2 pulse-
average, corresponding to 15 MPa peak compressional and 3.7 MPa rarefactional pressure .
Further details can be found in "HIFU Transducer Characterization Using a Robust Needle Hydrophone", Proceedings
of the International Society for Therapeutic Ultrasound, Oxford, UK, Aug. 29- Sept 2, 2006.

Mechanical Specifications

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