| 摘要 |
A curved transducer array or a flat array with an acoustic converging lens functions as a fixed focus physical lens and is focused near maximum range. At longer ranges the full aperture is utilized for good resolution, and at shorter ranges up to a specified fraction of maximum range improved resolution is achieved by a dynamic aperture control which increases the array aperture by steps by switching in more transducer elements. This simplified sector scanner does not require dynamic electronic focusing. |
