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Ultrasound, Acoustic Paramters Calculation. Technical Description of Color Doppler Ultrasound - BIOE 414 Instrumentation Projects - University of Illinois - Engineering Wiki. [Introduction] [History] [Principles of Ultrasound] [Biomedical Significance] [Technical Description] [Instrument Observation] [Artifacts] [Interviews] [Future Direction] [Project Conclusion] The iE55 receives echo voltages from the transducer and display them in the form of anatomic images. The instrument is composed of a beam former, a signal processor, an image processor and a display. [1] Beam Former The first stage of the instrument is the beam former. Pulser The pulser is the source of ultrasound signal. Pulse Delay The pulse delay takes care of the sequencing of pulse, phase delays and the variations in the pulse amplitudes.

Transmit and Receive Switch During transmission, the T/R switch directs the driving voltage from the pulser to the transducer. Amplifiers The beam former increase the voltage amplitude of the echo voltages. A/D Converters The amplified echo voltages need to be digitized for the next step. Summer All the signals components are added together in the last step. Basic ultrasound, echocardiography and Doppler ultrasound. Basic ultrasound, echocardiography and Doppler for clinicians by Asbjørn Støylen, dr. med. This section updated: November 2013 This web page is intended as an introduction to basic ultrasound physics and technology for clinicians without technical or mathematical background. A basic knowledge of the physical principles underlying ultrasound, will give a better understanding of the practical limitations in ultrasound, and the technical solutions used to solve the problems. This will give a clearer picture of the reasons for the problems and artifacts.

Technical or mathematical background is not necessary, explanations are intended to be intuitive and graphic, rather than mathematical. This section is important for the understanding of the basic principles described in detail in the section on measurements of strain rate by ultrasound. Section index Back to website index Next section: Measurements of strain and strain rate by Ultrasound Related section: Mathemathics of strain and strain rate . Elektronica_072009_English. Cookiedetectresponse. Community College Ultrasonic Testing. Overview of Ultrasound Imaging Systems and the Electrical Components Required for Main Subfunctions. Abstract: This application note is an introduction to ultrasound imaging systems. It discusses the trend towards smaller, lower cost, and more portable imaging solutions, while explaining what is required to maintain the performance and diagnostic capabilities found in larger cart-based systems.

The system subfunctions and electrical components for an ultrasound system are outlined. This discussion focuses on transducers, high-voltage multiplexing, high-voltage transmitters, image-path receivers, digital beamformers, beamformed digital-signal processing, and display processing. Overview By transmitting acoustic energy into the body and receiving and processing the returning reflections, phased-array ultrasound systems can generate images of internal organs and structures, map blood flow and tissue motion, and provide highly accurate blood velocity information.

Transducers A critical component of this system is the ultrasound transducer. High-Voltage Multiplexing High-Voltage Transmitters. Ultrasound Production and Interactions. The amplitude of an ultrasound pulse is the range of pressure excursions as below. Ultrasound Pulse Amplitude, Intensity, and Energy . The pressure is related to the degree of tissue displacement caused by the vibration.

The amplitude is related to the energy content, or "loudness," of the ultrasound pulse. The amplitude of the pulse as it leaves the transducer is generally determined by how hard the crystal is "struck" by the electrical pulse. Most systems have a control on the pulse generator that changes the size of the electrical pulse and the ultrasound pulse amplitude.

In diagnostic applications, it is usually necessary to know only the relative amplitude of ultrasound pulses. Relative amplitude (ratio) = A2/A1. There are advantages in expressing relative pulse amplitude in terms of the logarithm of the amplitude ratio. Relative amplitude (dB) = 20 log A2/A1 The following illustration compares decibel values to pulse amplitude ratios and percent values.