History of Ultrasonics

Ultrasound

Shortly after the close of world war II, researchers in Japan began to explore the medical diagnostic capabilities of ultrasound. The first ultrasonic instruments used an A-mode presentation with blips on an oscilloscope screen. That was followed by a B-mode presentation with a two dimensional, gray scale image.

Japan's work in ultrasound was relatively unknown in the United States and Europe untill the 1950s. Researchers then presented their findings on the use of ultrasound to detect gallstones, breast masses, and tumors to the international medical community. Japan was also the first country to apply Doppler ultrasound, an application of ultrasound that detects internal moving objects such as blood coursing through the heart for cardiovascular investigation.

Ultrasound pioneers working in the United States contributed many innovations and important discoveries to the field during the following decades. Researchers learned to use ultrasound to detect potential cancer and to visualize tumors in living subjects and in excised tissue. Real-time imaging, another significant diagnostic fool for physicians, presented ultrasound images directly on the system's CRT screen at the time of scanning. The introduction of spectral Doppler and later color Doppler depicted bood flow in various colors to indicate the speed and direction of the flow.

The United States also produced the earliest hand held "contact" scanner for clinical use, the second generation of B-mode equipment, and the prototype for the first articulated-arm hand held scanner, with 2-D images.

The history of ultrasonics

In 1917, French physicist Paul Langevin developed the first practical ultrasonic generator, which was capable of producing high-frequency sound waves of up to 20 kHz. Langevin used his ultrasonic generator to study the properties of solids and liquids, and he also discovered that the sound waves could be used to detect flaws in metal.

In the 1930s, engineers and scientists in the United States, Canada, and Europe began to experiment with ultrasonics for industrial applications. They developed techniques for using ultrasonic waves to inspect metal parts for defects, such as cracks and voids.

During World War II, ultrasonics was used to inspect the quality of welds in military equipment. This was an important application as it allowed for quick and non-destructive testing of the military equipment, which helped to improve the safety and reliability of the equipment.

In the 1950s, ultrasonics began to be used for medical imaging, such as for prenatal ultrasound scans.

In the 1960s, the use of ultrasonics expanded to the aerospace and automotive industries, where it was used to inspect the quality of aircraft and car parts.

In the 1970s, advances in electronic technology led to the development of more sophisticated ultrasonic testing equipment, which made it possible to detect smaller defects and to inspect thicker and more complex materials.

Today, ultrasonics is widely used in various industries, including aerospace, automotive, power generation, shipbuilding, and many more. It has become an essential tool for non-destructive testing and quality control, allowing for the safe and efficient inspection of materials and components.

Ultrasonics technology is still evolving, for example, in the recent years, the development of phased arrays and the integration of artificial intelligence (AI) techniques have led to new possibilities for ultrasonics testing, such as remote inspection and automation.

Beginnings of Nondestructive Evaluation (NDE)

Nondestructive testing has been practiced for many decades, with initial rapid developments in instrumentation spurred by the technological advances that occurred during World War II and the detection of defects. As a part of "safe life" design, it was intended that a structure should not develop macroscopic defects during its life, with the detection of such defects being a cause for removal of the component from service. In response to this need, increasingly sophisticated techniques using ultrasonics, eddy currents, x-rays, dye penetrants, magnetic particles, and other forms in interrogating energy emerged.

In the early 1970's two events occurred which caused a major change in the NDT field. First, improvements in the technology led to the ability to detect small flaws, which caused more parts to be rejected even though the probability of component failure had not changed. However, the discipline of fracture mechanics emerged, which enabled one to predict whether a crack of a given size will fail under a particular load when a material's fracture toughness properties are known. Other laws were developed to predict the growth rate of cracks under cyclic loading (fatigue). With the advent of these tools, it became possible to accept structures containing defects if the sizes of those defects were known. This formed the basis for the new philosophy of "damage tolerant" design. Components having known defects could continue in service as long as it could be established that those defects would not grow to a critical, failure producing size. A new challenge was thus presented to the nondestructive testing community. Detection was not enough. One needed to also obtain quantitative information about flaw size to serve as an input to fracture mechanics based predictions of remaining life. The need for quantitative information was particularly strongly in the defense and nuclear power industries and led to the emergence of quantitative nondestructive evaluation (QNDE) as a new engineering/research discipline. A number of research programs around the world were started, such as the center for nondestructive evaluation at Iowa State University (growing out of a major research effort at the Rockwell International Science Center); the Electric Power Reserach Institute in Charlotte, North Carolina; the Fraunhofer Institute for Nondestructive Testing in Saarbrucken, Germany; and the Nondestructive Testing Centre in Harwel, England.

Who invented ultrasound

Ultrasound technology, also known as ultrasonography or medical sonography, was developed over several decades by multiple scientists and engineers. It was not the invention of a single individual, but rather the result of collaborative efforts and incremental advancements in various fields. Here are some key milestones and contributors in the development of ultrasound:

Early Discoveries (Late 19th and Early 20th Centuries):

French physicist Pierre Curie and his brother Jacques Curie made significant contributions to piezoelectricity, a phenomenon involving certain crystals that produce electrical charges when mechanical stress is applied. This discovery laid the foundation for ultrasound transducers.

World War I (1914-1918):

During World War I, researchers like Paul Langevin and his colleagues developed underwater sonar technology, which used ultrasonic waves to detect submarines. This technology marked one of the earliest practical applications of ultrasound.

1930s and 1940s:

Researchers in various countries, including Karl Dussik in Austria and Ian Donald in Scotland, began experimenting with ultrasound for medical purposes. Dussik conducted early experiments using ultrasound to image the brain.

1950s:

George Ludwig, a physicist, and Douglas Howry, a radiologist, developed the first practical ultrasound machine for medical imaging in the United States. This machine, known as the "Reflectoscope," was used for obstetric and gynecological examinations.

1960s:

Continuous-wave Doppler ultrasound was developed, allowing for the measurement of blood flow in the body. This innovation was instrumental in cardiology and vascular medicine.

1970s:

Real-time ultrasound imaging technology was developed, enabling dynamic, moving images of the human body. This advancement significantly improved the diagnostic capabilities of ultrasound.

1980s and Beyond:

Advances in ultrasound technology continued, with the development of color Doppler, 3D ultrasound, and 4D ultrasound (real-time 3D). These innovations expanded the range of applications and improved the quality of diagnostic imaging.

It's important to note that ultrasound technology has applications beyond medical imaging, including industrial testing, materials inspection, and underwater exploration. The development of ultrasound technology has been a collaborative effort involving physicists, engineers, and medical professionals over many years.

Why ultrasonic sensor is used

Ultrasonic sensors are used in various applications across different industries due to their ability to measure distances, detect objects, and provide non-contact sensing solutions. These sensors operate by emitting ultrasonic waves (high-frequency sound waves) and measuring the time it takes for the waves to bounce off an object and return to the sensor. Here are some common reasons why ultrasonic sensors are used:

Distance Measurement: Ultrasonic sensors are widely employed for accurately measuring distances to objects without physical contact. They are capable of providing precise distance readings, making them valuable in applications such as:

Industrial automation: For object detection and position control in manufacturing processes.
Robotics: For obstacle avoidance and navigation.
Automotive: In parking assist systems, collision avoidance, and adaptive cruise control.
Home appliances: In washing machines, dishwashers, and robotic vacuum cleaners for obstacle detection.

Object Detection and Presence Sensing: Ultrasonic sensors are effective at detecting the presence or absence of objects in their field of view. They are commonly used in:

Security systems: For detecting intruders or unauthorized access.
Retail: In automatic doors, vending machines, and inventory management.
Conveyor systems: For object counting and sorting.
Parking garages: To monitor vehicle occupancy.

Liquid Level Measurement: Ultrasonic sensors are capable of accurately measuring the level of liquids in tanks or containers. This is essential in industries such as:

Agriculture: For monitoring water levels in irrigation systems.
Chemical processing: In storage tanks and chemical reactors.
Environmental monitoring: In wastewater treatment plants and reservoirs.

Flow Rate Measurement: Ultrasonic sensors can measure the flow rate of liquids or gases by assessing the speed of sound in the fluid. This is useful in applications like:

Water and wastewater treatment: For monitoring flow rates and controlling processes.
Oil and gas industry: In flow meters for custody transfer and process control.

Proximity Sensing: Ultrasonic sensors can detect the proximity of objects or individuals without physical contact. They are used in:

Home automation: For touchless light switches and faucets.
Healthcare: In touchless hand sanitizers and soap dispensers.
Human-computer interaction: In gesture recognition systems.

Level and Depth Sensing: In addition to liquid level measurement, ultrasonic sensors are used to measure the depth of bodies of water, including rivers, lakes, and oceans. This is valuable in hydrology, environmental monitoring, and navigation.

Obstacle Avoidance: In robotics and autonomous vehicles, ultrasonic sensors are used for obstacle detection and avoidance. They help ensure safe navigation in various environments.

Quality Control: In manufacturing, ultrasonic sensors are used for quality control by detecting defects or irregularities in products, such as measuring the thickness of materials or inspecting welds.

Ultrasonic sensors offer advantages such as non-contact operation, high accuracy, and reliability in a wide range of environmental conditions. Their versatility and ability to provide precise measurements make them essential in numerous applications across industries.

Are ultrasonic waves harmful

Ultrasonic waves, which are sound waves with frequencies higher than the upper limit of human hearing (typically above 20,000 hertz), are generally considered safe for humans when used within appropriate limits. In fact, ultrasonic waves have many practical and beneficial applications in various fields. However, their safety depends on several factors:

Frequency and Intensity: The safety of ultrasonic waves depends on the frequency and intensity of the waves. Higher frequencies and intensities can potentially cause more harm. Most common ultrasonic applications, such as medical imaging, industrial testing, and object detection, use frequencies well within safe limits for humans.

Exposure Duration: The duration of exposure to ultrasonic waves matters. Short-term exposure to low-intensity ultrasonic waves, such as those used in medical imaging, is generally safe. Prolonged exposure to high-intensity ultrasound can lead to tissue heating and potential harm.

Distance from the Source: The closer a person is to the source of ultrasonic waves, the higher the potential risk. Many ultrasonic applications, like medical ultrasound, are designed to focus the waves on a specific area, minimizing exposure to surrounding tissues.

Frequency Range: Different tissues and materials in the body have varying responses to ultrasound waves depending on their composition and density. Medical ultrasound, for example, carefully selects frequencies and intensities that are safe for imaging soft tissues.

Regulations and Guidelines: Regulatory agencies and organizations, such as the FDA (U.S. Food and Drug Administration) for medical devices, establish safety guidelines and limits for the use of ultrasound. Adherence to these guidelines is essential for ensuring safety in medical and industrial applications.

Common uses of ultrasonic waves that are considered safe include:

Medical Imaging: Ultrasound imaging (sonography) is widely used for diagnostic purposes in obstetrics, cardiology, and various medical specialties. It is non-invasive and generally safe for both patients and healthcare providers.

Industrial Testing: Ultrasonic testing is used to inspect materials for defects, thickness measurements, and flaw detection in structures and components. It is safe when conducted following established safety protocols.

Object Detection: Ultrasonic sensors in devices like parking assist systems, robotics, and home automation are designed to emit low-intensity ultrasonic waves and are considered safe for human interaction.

However, it's essential to follow safety guidelines and best practices when using ultrasonic devices, especially in medical and industrial settings where higher intensities are involved. Incorrect or prolonged exposure to high-intensity ultrasonic waves can potentially cause tissue damage or harm.

In summary, ultrasonic waves are generally safe when used within safe frequency and intensity limits and in accordance with established guidelines and safety practices. Proper equipment design and operator training are crucial for ensuring safety in various ultrasonic applications.

History of ultrasound

The history of ultrasound, or ultrasonography, is a fascinating journey of scientific discovery and technological innovation. Ultrasound technology has evolved over the years, and its applications have expanded across various fields, including medicine, industry, and more. Here's an overview of the key milestones in the history of ultrasound:

Early Discoveries (Late 19th and Early 20th Centuries):

The groundwork for ultrasound technology was laid by discoveries in acoustics and the properties of sound waves. Scientists like Pierre Curie and Jacques Curie in France made significant contributions to the understanding of piezoelectricity, which is the ability of certain materials to generate electrical charges when subjected to mechanical stress.

World War I (1914-1918):

During World War I, researchers like Paul Langevin, a French physicist, developed underwater sonar technology using ultrasonic waves to detect submarines. This marked one of the earliest practical applications of ultrasound.

1930s and 1940s:

Researchers began experimenting with ultrasound for medical purposes. Karl Dussik, an Austrian neurologist, conducted early experiments using ultrasound to image the brain. These early attempts laid the foundation for medical ultrasound imaging.

1950s:

George Ludwig, a physicist, and Douglas Howry, a radiologist, developed the first practical ultrasound machine for medical imaging in the United States. This machine, known as the "Reflectoscope," was used for obstetric and gynecological examinations.

1960s:

Continuous-wave Doppler ultrasound was developed, allowing for the measurement of blood flow in the body. This innovation was instrumental in cardiology and vascular medicine.

1970s:

Real-time ultrasound imaging technology was developed, enabling dynamic, moving images of the human body. This advancement significantly improved the diagnostic capabilities of ultrasound.

1980s and Beyond:

Advances in ultrasound technology continued, with the development of color Doppler, 3D ultrasound, and 4D ultrasound (real-time 3D). These innovations expanded the range of applications and improved the quality of diagnostic imaging.

Non-Medical Applications:

Ultrasound technology found applications beyond medicine, including industrial testing, materials inspection, underwater exploration, and more. It became a valuable tool for non-destructive testing and quality control.

Current Applications:

Today, ultrasound is widely used in various medical specialties, including obstetrics, cardiology, radiology, and urology. It plays a crucial role in diagnosing and monitoring various medical conditions.

Ongoing Research:

Ongoing research and development continue to push the boundaries of ultrasound technology, leading to innovations in areas such as therapeutic ultrasound (ultrasound for medical treatments), point-of-care ultrasound devices, and more.

The history of ultrasound reflects the collaborative efforts of physicists, engineers, and medical professionals over many decades. This technology has revolutionized medical diagnostics and has become an indispensable tool in modern healthcare while finding diverse applications in other industries as well.

Is ultrasonic and ultrasound the same

"Ultrasonic" and "ultrasound" are related terms, but they have distinct meanings and are used in different contexts:

Ultrasonic:

"Ultrasonic" is an adjective that describes sound waves or vibrations at frequencies higher than the upper limit of human hearing. In other words, it refers to sound waves with frequencies above the audible range for humans, which is typically considered to be around 20,000 hertz (Hz).
Ultrasonic waves are characterized by their high frequency and are often used in various applications, including medical imaging, industrial testing, cleaning, and object detection. Ultrasonic sensors, for example, emit and receive ultrasonic waves to measure distances or detect objects.

Ultrasound:

"Ultrasound" is a noun that specifically refers to the diagnostic imaging technique that uses high-frequency sound waves to create images of the inside of the human body or objects. It is commonly used in medical diagnostics to visualize internal organs, tissues, and structures.
In medical ultrasound, a transducer emits ultrasonic waves into the body, and the waves bounce back (echo) when they encounter different tissues or structures. By analyzing the echoes, a computer creates real-time images that can be used for medical diagnosis and monitoring.

In summary, "ultrasonic" is a broader term that describes sound waves with frequencies beyond human hearing, while "ultrasound" is a specific application of ultrasonic waves in medical imaging. Ultrasound technology uses ultrasonic waves to create images and is commonly referred to as "ultrasound imaging" or simply "ultrasound" in the medical field.