Application of advanced technology of micro computer, Digital Scanning Converter (DSC), variable aperture, multi-section dynamic focusing, high dynamic, low noise, wide band pre-amplifier, log compression, TGC control, dynamic filtering, edge enhancement and frame correlation etc, to get high resolution and sharp images. Four display mode: B, BB, BM, M Grey scales: 256 grades The image can be displayed in real time, frozenm amplified, black-white reversed, up and down conversed and upgraded in depth in real time. Standard PAL-D and VGA video output, available to access to the large screen monitor, video cassette recorder and video image printer etc. Optional probes and built-in color coding module. General gain control, near field and far field (T.G.C) control, brightness and contrast adjustment. Foldaway keyboard and trackball are equipped to get fast, convenient and flexible operation. The device is portable structured with plastic cover. Switch power is used without working frequency transformer. Various programmable devices and SMT in the device make the device high integrated, small volume and light weighted. The device passed the clinical verification of safety and diagnosis validity.