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In our lives today we have had to appreciate the importance of technology, especially in the medical sector. Many people are familiar with the medical applications of ultrasonic imaging, in which high frequency sound waves are used to create highly detailed cross-sectional pictures of internal organs. Doctors are now able to work with a lot of accuracy and efficiency, because discoveries of better analysis have improved through technology. Among the discoveries that are recently being used is the use of ultrasound transducers, transducers are devices that convert one form of energy to another. In context,(Smith), Anything that converts energy into another form is simply known as a transducer.
Transducers can be divided into two, actuators and sensors as major categories.
Sensors are mostly used to transform energy in physical form, such as in speakers and microphones. They change the transmission of one form of energy to another with according to the objective. E.g. in a speaker, sound energy is produced when electrical energy is transformed by a coil to produce sound energy.
Actuators convert electrical energy to physical one in a way that only the physical object is relayed. Such energy transformation includes the ringing of a bell. Such energy, which is electronically passed in form of a ringing sound, comes from an actuator, in this case a bell.
Mostly transducers are used in sonography (ultrasound) laboratory. They are known as ultrasound transducers. Imaging technology nowadays is in wide range of applications, in maternal monitory and in surgery. Advanced imaging transducers have led to image production that is more of quality and high resolution. For a complete image, an array of transducers is used to construct an image consisting of multiple angles. Experts in the medical field assert that the risk of using ultrasound technology is little and worth no worry.
A transducer consists of many small elements. An element is a multilayer sandwich of piezoelectric and other materials. Piezoelectric transducer is a commonly used piezoelectric ceramic sensor material having an acoustic impedance between 28 and 36x10^6 kg/m2s (Rayl). To improve coupling, a front matching layer, a coupling material with intermediate acoustic impedance, is added to the front face of the piezoelectric to aid in transferring the sound wave more efficiently to and from the body. An acoustically absorbing material called a backing is added to the back of the sensor to dampen energy that might cause additional mechanical vibrations. An important aspect in ultrasound imaging is the ability to detect and resolve small structures in the body. This is largely determined by how well the beam is focused. Beam focusing for linear and phased arrays is determined by two different measures: elevation beam width and lateral beam width.
According to Nelligan,Ultrasound imaging technology in sonography laboratories comprises the use of transducers commonly known as phased arrays. Phased arrays not only apply in medical purposes, but some industries have discovered this technology and now use it to provide new levels of information and visualization, which include crack detection, bond testing and material thickness. Phased arrays consist of a transducers assembly of 16 to as many as 256 small individual elements by which each can be transmitted separately. They can be arranged in a linear, single phased or take a linear curvature or more combined shapes. Phased array design may be for direct use or indirect.
Linear Phased transducers
This transducers offer several new technologies, one of which is continuous steering of the image. Since color flow and Doppler imaging are based on the Doppler principle, they are most sensitive when the blood vessels and the blood carry point towards or away from the transducers. The continuous steering is made possible by combining 288 transducers elements into 128 signal paths, which match the 128 channels on the ultrasound system.
Advantages of Ultrasound transducers
Scanning is more effective since with phased array time taken is less. It is more flexible, as phased array can change the direction of image processing. It hassmall matrix arrays that give significantly more flexibility than conventional probes for inspecting restricted areas. With a very strong imaging information can be displayed as.
Disadvantages of transducers
Limited image resolution: due to the time this problem will be solved, but still there are many situations where images have much higher resolution. And also where they are bones no clear vision is obtained.
Reflection in gas areas: this means that in areas where there gases, ultrasound is not applicable.
As medicine takes a higher notch in terms of technology, it is observed that imaging technology is much taken in consideration. The transducers have formed a basis for better services in medicine. Sonographers have had reduced work in return to less time spent in analysis and presentation of results. With the improved image quality, improved ergonomics, and trapezoidal imaging format, doctors are now able to provide more accurate diagnoses.