From Fukuda Denshi Co., Ltd.;
'With a variety of advanced functions, the CFsonic UF-7700 provides high-resolution images and enhanced Doppler information. The high-end system allows to enjoy the multiple features through the excellent user interface. It establishes a new high-quality imaging environment.'

From SIUI Inc.;
'The CTS-310B is designed for the diagnosis of liver, gall, kidney, pancreas, thyroid, breast, uterus, bladder, ovary, etc. It is a versatile ultrasound scanner with both linear array scanning and convex scanning.'
Features:
'Powerful image processing circuit & High quality image
A wide range of probes for selection
Cineloop
Probe frequency conversation option
Computer image communication
Various measuring function
Backlit keyboard'

From SIUI Inc.;
'Incorporating the latest advances in technology, the CTS-6000 digital B/W ultrasound system provides exceptional imaging quality and complete diagnostic capabilities. It is equipped with extensive analysis package, super broadband multifrequency probes and disk storage capacity, a complete system that fully meets different clinical needs.
CTS-6000 sets a new standard for digital ultrasound imaging.'

(CHI) Contrast harmonic imaging is an ultrasound technique to improve the measurement of blood perfusion or capillary blood flow. Based on the nonlinear properties of contrast agents, CHI transmits at the fundamental frequency but receives at the second harmonic. Contrast enhanced echo signals contain significant energy components at higher harmonics (bubbles acts as harmonic oscillators), while tissue echoes do not. Caused by that contrast signal can be separated from tissue echoes by the characteristic signal.
In combination with the pulse inversion technique, CHI promises very high contrast agent sensitivity with high spatial resolution.

See also Ultrasound Contrast Agent Safety and Hemoglobin.

To calculate the echo position, a constant sound speed of 1538.5 m/sec is assumed. Tissue penetration is frequency depended, if the frequency increases, the imaging depth decreases. The range resolution defines the depth. Ultrasound propagating in tissue is attenuated due to scattering and absorption. The attenuation is proportional to depth and frequency and is typically in the range from 0.5 to 1 dB/(MHz cm).

See also Attenuation Coefficient, Proximity Sensor, and Echo Ranging.