Another great invention of “the father of the phone” – hearing aids

Did you know that Bell, who is known as the “father of the telephone”, also invented the hearing aid, which was improved on the basis of the phonograph invented by Edison.

1878In the year, American scientist Bell invented the first carbon hearing aid. Hearing aids are assembled from carbon microphones, earphones, batteries, wires and other components.

1890Year, Austrian scientistFerdinant AltThe first generation of hearing aids was prepared.

The first electronic hearing aid

1904Year, Danish Hans De Mante (HansDemantAnd the US Lacey Hutchison (ResseHutchison) Co-invested in mass production of hearing aids. To20century40In the ages, there were two types of hearing aids: air conduction and bone conduction. During this period, hearing aids 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 and loud volume, such as17Inch TV, not easy to carry.

1920In the year, shortly after the appearance of thermionic vacuum tube (hot cathode tube), a vacuum tube hearing aid appeared. With the continuous development of vacuum tube technology, the volume of the hearing aid is gradually reduced, and the separation of the main battery is realized.1921In the year, the UK first produced commercial tube auxiliary equipment. Because the tube requires two power supplies (one is to heat the filament in the tube to emit electrons; the other is to drive the electrons through the grid to the anode. Therefore, the hearing aid is large and bulky. Although the gain and clarity are better, it is hardly May carry. Over time, mercury batteries replaced zinc batteries, resulting in a significant reduction in the size of the battery, and finally the battery and hearing aids can be combined. During the Second World War, new technologies such as printed circuits and ceramic capacitors appeared. The material has led to a significant reduction in the size of the integrated hearing aid, allowing the hearing aid to be carried around. Gradually, the hearing aid is also beginning to use peaks (pc) and compression (aGC) and other technologies.

The father of the phone

1943In the year, the development of integrated hearing aids began with the installation of power supplies, microphones and loudspeakers in a small box, which is the prototype of modern box hearing aids. In the same year, Denmark established two factories that produced hearing aids on a large scale.OticonOne isDanavox. The size of hearing aids is getting smaller and smaller. In the end, the game is as big as a cigarette case and it is very convenient to carry.

1948In the year of semiconductors, electronic engineers immediately applied semiconductor technology to hearing aids and achieved good results. The use of some semiconductor components can further reduce the volume of the hearing aid. Acoustic feedback will be inevitable if all semiconductor components are used.

1953In the year, the introduction of transistor hearing aids made it possible for hearing aids to develop into miniaturization. 1954In the year, glasses-type hearing aids appeared. To avoid acoustic feedback, the designer placed the receiver and microphone on the arms on either side, but failed to achieve binaural wear. 1955In the year, a single-body eyeglass-type hearing aid was introduced on a single temple, making it possible to wear a hearing aid in both ears.

1956In the year, the ear canal hearing aid was manufactured, which not only further reduced the volume, but also exceeded the glasses and card hearing aids, becoming the world’s largest sales channel for hearing aids.

Hearing aid inventor

1957In the year, artificial hearing aids were introduced. The new ceramic microphone has a wide and flat frequency that overcomes the shortcomings of conventional piezoelectric crystals. The appearance of tantalum capacitors further reduces the capacitance volume, and the transistor circuit rapidly develops in the direction of miniaturization of integrated circuits. With the advent of large scale integrated circuits, the volume of hearing aids has been further reduced. Shortly after the emergence of hearing aids in the ear, half ear studs, ear canals, and full ear canal hearing aids appeared one after another, largely satisfying the psychological and aesthetic needs of patients.

1958In the year, China began to produce box-type hearing aids.

1988In the year, a programmable hearing aid was used to modify some listening programs with remote controls for the most comfortable listening experience. Programmable hearing aids use wide-angle microphones and directional microphone hearing aids to use different listening modes in everyday life and noisy environments to make the sounds clearer. People with directional hearing aids don’t look at you, but he is listening to your speech, so listening seems to have a special purpose. It is said that the former president of the United States wears such hearing aids.

Old-fashioned hearing aid

The advent of integrated circuits quickly replaced “transistor hearing aids.” integrated circuitICto1964Launched in the year. They are lightweight, low power and more stable. In recent years, with the rapid development of science and technology, hearing aids have gradually developed into intelligent and internalized:1982In the year, the advent of the “electret microphone” achieved the miniaturization of hearing aids, and the sensitivity and clarity reached a new level. ;With the advent of “computer-programmed hearing aids”, the benefits of hearing aids have initially been intelligently adjusted, and hearing aids have reached another new level. 1997In the year, the “Digital Hearing Aid” was intelligently adjusted, which was extremely convenient to use and had higher performance.

With the development of hearing aid technology, it has now been launched.Full digital hearing aidThe performance is much higher than that of the analog computer, which makes the deaf patients have a better experience and comfort.

Link:Another great invention of "the father of the phone" - hearing aids

REF: Hearing aids ChinaHearing amplifierDigital Hearing Aids
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