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What is Ultrasound?
History of Ultrasound
Perception in humans and animals
Applications of Ultrasound
What is Ultrasound?
History of Ultrasound
Perception in humans and animals
Applications of Ultrasound
Ultrasound is an oscillating sound
pressure wave with a frequency greater
than the upper limit of the human hearing
range.
Ultrasound devices operate with
frequencies from 20 kHz up to several
gigahertz.
Ultrasonic is the application of ultrasound.
Ultrasound can be used for medical imaging,
detection, measurement and cleaning. At higher
power levels, ultrasonic is useful for changing the chemical properties of
substances
What is Ultrasound?
History of Ultrasound
Perception in humans and animals
Applications of Ultrasound
1794
A.D.
1917
A.D.
600
B.C.
1893
A.D.
Acoustics, the science of sound, starts as far back as Pythagoras, who wrote on the mathematical properties of stringed instruments.
Echolocation in bats was discovered by Lazzaro Spallanzani, when he demonstrated that bats hunted and navigated by inaudible sound and not vision.
Sir Francis Galton constructed a whistle producing ultrasound
The first technological application of ultrasound was an attempt to detect submarines by Paul Langevin
What is Ultrasound?
History of Ultrasound
Perception in humans and animals
Applications of Ultrasound
Perception
Humans
The upper frequency limit in humans (approximately 20 kHz) is due to
limitations of the middle ear
Children can hear some high-pitched sounds that older adults cannot hear,
because in humans the upper limit pitch of hearing tends to decrease with
age
Animals
Bats use a variety of ultrasonic ranging (echolocation) techniques to detect
their prey. They can detect frequencies beyond 100 kHz, possibly up to 200
kHz
Many insects have good ultrasonic hearing and most of these are nocturnal insects listening for echo locating bats
Dogs with normal hearing can hear ultrasound. A dog whistle exploits this by emitting a high frequency sound to call to
a dog.
Whales and dolphins can hear ultrasound and use such sounds in their navigational system (bio sonar) to orient and capture
prey.
What is Ultrasound?
History of Ultrasound
Perception in humans and animals
Applications of Ultrasound
Non-contact sensor
Motion sensors
Non-destructive testing
Sonar USID
An ultrasonic level or sensing system requires no contact with the target
It uses either Continues or pulsed Waves
It transmit signals of Ultrasonic Waves and then the transmitter waits for a return Signal
Automatic door openers use ultrasonic Sensors to detect people’s approach
It can be used to detect intruders
Polaroid SX-70 camera which included a light-weight transducer system to focus the camera automatically.
Ultrasonic Testing is a type of non-destructive testing
It is used to find flaws in materials and measure their size and thickness
The range between 2 Hz and 10 KHz is used to inspect most metals and plastics
The range between 50 KHz and 500 KHz is used to inspect lower Dense Material such as wood, concrete, and cement
It is the use of ultrasound in underwater Range Finding
It generates a pulse in a certain direction. If there is an object in the path. The object will reflect it back as an echo. The distance is measured by the time the echo have taken to return
It uses Tags or Badges, which has substances attached to it, in order to determine their location
These Badges or tags transmit an ultrasound signal to communicate their location to microphone sensors
ImagingAcoustic
microscopyMedical
SonographyBiomedical
ApplicationsUltrasonic Cleaning
Ultrasonic Imaging Uses Frequencies of 2 MHz and Density of less than 1 Watt
It is used to get pictures in good Resolution of bodies and Tissues
It uses sound waves to visualize structures too small to be seen by the human eye.
The reflection and diffraction of sound wave can show data that is not available even by light waves
It is the use of ultrasound to create medical images of muscles, tendons, and internal organs
It takes the size, Structure, and any pathological lesions and this is the method used to view babies
It can break up stony Deposits
Accelerates the effect of drug in certain places
Assist in the measurement of the elastics properties of tissue
Frequency between 20 to 40 KHz to clean jewelry, lenses, and even surgical instruments
When the bubbles collapse the form tiny jets that are directed at the surface
The method is the collapsing of millions of small cavitations on the dirty surface
Ultrasonic disintegration
UltrasonicWelding
Weapons Sonochemistry
It functions just like the Ultrasonic Cleaning
It breaks down Bacteria and other biological cells
It is used at a level of high frequencies and low amplitudes in order to join plastics together
Ultrasound has been studied as a basis for sonic weapons
Disorientation of attackers, up to lethal levels of sound.
Riot control
The ultrasound helps in chemical reactions
It also breaks up solids and removes inert material layers
It generates extreme temperatures and pressure in liquid
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