The hearing aid in the first sense was invented in the 17th century. His styling was inspired by the palm of his hand to collect sound around the ear. Made a "hearing aid" like a horn. They look strange and vary in size. Some shapes are like a water pipe, some are like a big hat, and so on. At that time, people thought that the longer the length of the "hearing aid" was, the clearer the sound heard, so the "hearing aids" at that time were very long. Some lengths can reach a length of one meter. Now, people at that time are not very funny. It is the simple mechanical device of the hearing aid that has been used for centuries and has been used in the 19th century.
In 1878, the first charcoal hearing aid was invented by American scientist bell. The hearing aid is assembled from components such as carbon microphones, earphones, batteries, and wires.
In 1890, the Austrian scientist Ferdinant Alt prepared the first generation of tube hearing aids.
In 1904, Danish Hans Demant and American Resse Hutchison jointly invested in mass production of hearing aids.
By the 1940s, there were already two types of hearing aids, air conduction and bone conduction.
The hearing aids of this period have been greatly developed and improved in technology. Although they can meet the needs of some deaf people, there are still many shortcomings, such as too much noise, bulky, such as 17-inch TV sets, not easy to carry, etc.
In 1920, a thermal ion vacuum tube (hot cathode tube) vacuum tube hearing aid was born.
In 1921, the UK produced the first commercial tube hearing aid.
In 1943, the development of integrated hearing aids, the power supply, microphone and amplifier in a small box, the prototype of modern box hearing aids
In 1948, semiconductors came out, and electronic engineers immediately applied semiconductor technology to hearing aids for better results.
In 1953, transistor hearing aids were introduced, making it possible for hearing aids to develop in miniaturization.
In 1956, the ear-back hearing aid was made, which not only further reduced the size, but also surpassed the glasses-type and box-type hearing aids, and became the world's largest sales aid.
In 1957, an in-ear hearing aid was introduced. The new ceramic microphones have a wide and flat frequency, which overcomes the shortcomings of conventional piezoelectric crystals. The appearance of tantalum capacitors further reduces the capacitance volume, and the transistor circuit develops rapidly toward the miniaturization of integrated circuits.
A programmable hearing aid that appeared in 1988, using a remote control to transform multiple listening programs for the most comfortable listening experience.
In recent years, "digital" hearing aids have been introduced, and the digital signal processing capability is extremely strong, providing greater flexibility for the selection. The emergence of digital hearing aids has enabled the development of a wide range of hearing aids. Make hearing aids smaller, better, and more functional. Bring the gospel to hearing patients.
Current hearing aids are digital hearing aids. It works better than traditional hearing aids. The sound signal processing of the digital hearing aid is more detailed, and it is closer to the natural feeling of the human ear in terms of speech fidelity and sound quality. Different listening programs can be set according to the different usage environments of the users, and the switches can be automatically switched.
Not only that, digital hearing aids have many functions, and their functions are no longer limited to hearing. A Bluetooth-type hearing aid is a user that can connect to a multimedia device. You can watch TV, listen to music, call, and diversify. The definition of a hearing aid is no longer just a medical item. It is a high-tech consumer electronics. Today's people use hearing aids as a fashion item.
Existing hearing aid technology has been able to achieve noise reduction for environmental noise, but selective listening in the background noise environment still does not meet the needs of the wearer. In response, Dr. Gerald Kidd, a professor of the Department of Speech and Hearing Science at the University of Boston's Sargent College, led his team to develop a visually guided prototype of a hearing aid consisting of a microphone array and an eye tracker. composition. The microphone array consists of 16 microphones arranged in four rows facing rear. The eye tracker can sense the gaze of the eye and guide the direction of the microphone accordingly. Their current focus is on the coordination of the two components.
This study validates whether a vision-guided directional system can aid hearing loss in a background noise environment to address the challenges of selective listening in a background noise environment. There are other research teams that are beginning to be interested in this concept and are looking for similar approaches. This is a very promising direction that may make substantial progress in the future practical application of hearing aids, and may soon appear. Where can I listen to hearing aids?
A team led by Dr. Nima Mesgarani, associate professor of neurobiology and behavior at Columbia University's School of Electrical Engineering, showed that the brain's neural response to the target audience can be decoded. The Mesgarani team developed and tested an end-to-end system that selected specific audio receiving channels based on the decoded signals of the wearer's neural signals, each of which contained a full-range speaker. The system then automatically separates the target sound from the noise, analyzes which speaker the listener wants to listen to, and then magnifies the target sound to help the listener. The whole process takes less than 10 seconds. This work combines two advanced technologies - speech processing technology and auditory attention decoding technology.
Mesgarani said that there is no theoretical problem with the practical application of this technology in hearing aids. Several hearing aid companies have begun to pay attention to this technology and have expressed a keen interest in their projects.
Mesgarani said there are at least three more problems to be solved in this project. First, a stable and minimally invasive way to measure brain signals is needed. Second, a powerful algorithm is needed to analyze and process the sound according to the environment. Third, it is necessary to realize miniaturization of the system for practical application in the hearing aid. The good news is that these three challenges are all hot research areas, and each has significant progress. Mesgarani predicts that a cognitive-controlled hearing aid will be available within five years.
In the future, hearing aids will become a mobile phone and become a necessity. The 5G era may come later. The hearing aids will be an intelligent robot. Just like the intelligent butler in Iron Man, they can think independently and help the master to handle various affairs and calculate various information. We will wait and see what will happen to the hearing aid industry in the next decade!
