The whole process of Edison's invention of electric light

1878 In September, Edison began to study electric light, but because of Edison's economic problems, he had to seek financial support, so he set up a joint-stock company to provide financial support for the experiment. Soon, Lore found several shareholders who were willing to pay for Edison's electric light research.

However, Edison failed many times and soon spent 50 thousand dollars. The beliefs of some shareholders began to waver. Edison tried hard to persuade the shareholders to give Edison another $50,000. ?

1879 65438+1October 2 1, the electric lamp was successfully developed. He tried nearly 1600 materials for this purpose, and the filament of this electric lamp was burned out after 45 hours of continuous use. This is the first electric lamp with wide practical value. This kind of electric lamp includes "high resistance incandescent lamp" and "carbonized cotton filament lamp".

From 65438 to 0880, Edison sent assistants and experts all over the world to find suitable bamboos, about 6000 species, of which carbon fibers made of Japanese bamboo are the most practical, which can last for more than 1000 hours, achieving the purpose of durability. This kind of lamp is called "carbonized bamboo filament lamp".

188 1 year, at the Paris World Expo, Edison exhibited a 27-ton power generation equipment, which could be illuminated by 1200 electric lights.

1883, Edison observed that a copper wire was sealed in the light bulb during an electric lamp test, and thought that this could prevent the carbon wire from evaporating and prolong the life of the light bulb.

After repeated experiments, although the carbon wire evaporated as before, he found from this failure that after the carbon wire was heated, a weak current passed through the copper wire. Later, this phenomenon was called "Edison effect". 1904, the British physicist Fleming invented the electron tube according to the Edison effect.

Extended data

Edison's main achievements

1, phonograph

1877, Edison found that the diaphragm in the telephone transmitter would vibrate with the voice of speech, so he took a short needle and did an experiment, from which he was greatly inspired. Speech speed can make the short needle vibrate accordingly. On the other hand, this kind of vibration will definitely make the original sound, so he began to study the problem of sound reproduction.

/kloc-in August of 0/5, Edison asked his assistant to make a "strange machine" consisting of a large cylinder, a crank, a receiver and a diaphragm according to the pattern. When finished, Edison took out a piece of tin foil and rolled it on a metal cylinder engraved with spiral grooves, so that one end of the needle gently rubbed the tin foil to rotate.

The other end is connected to the receiver, then Edison shakes the crank to sing to the receiver, then puts the needle back in its original position, and then shakes the crank, and then the machine will release Edison's voice. In February 65438, Edison publicly demonstrated this "tin foil cylinder phonograph", which caused a sensation all over the world.

2. electric light

Contrary to popular understanding, Edison was not the inventor of electric light at first, but Edison improved it. As early as 180 1 year, a British chemist named humphry davy used platinum wire to electrify and glow in the laboratory. 18 10, he invented the "electric candle" which was illuminated by the arc between two charged carbon rods, which was the earliest prototype of the electric lamp.

Joseph swan, another British electrical engineer, after nearly 30 years' research, made a vacuum bulb with electricity and light from carbon wire in 1878+02.

The report about the swan's light bulb gave Edison a great inspiration. 1879 10, Edison finally succeeded in making an incandescent light bulb with carbon fiber as the filament, which is called "carbonized cotton filament incandescent lamp". Later, a large number of incandescent lamps were put into production, and companies were established to establish corresponding power stations, transmission networks and other infrastructure, which soon made electric lamps widely used in the United States.

During this period, he constantly improved his technology, and finally decided to use tungsten wire as the filament, which is called "tungsten lamp" and has been used ever since, so Edison became a recognized inventor of electric lamp. ?

3. movies.

Movable film camera: 1889, Edison invented the movable film camera. This camera uses a pointed gear to drive the tape with the width of 19 mm, and under the control of the ratchet wheel, it drives the tape to move intermittently and punch holes at the same time. This camera is driven by a motor, and the shutter shaft is connected to the phonograph. When the camera is running, the phonograph records sound and can take pictures continuously. ?

Movable film projector: 189 1 year, Edison invented the movable film projector, which is an early film projection equipment, and introduced the basic methods of film projection. The motor is used in front of the light source to make the film of continuous pictures rotate at high speed, thus creating the illusion of motion. The light source projects the image on the film onto the screen.

Audio film: 19 10, Edison invented a movie camera consisting of a phonograph and a camera. Under the energy of the motor, the camera's shading crankshaft is linked with the phonograph, which can record when the camera is running. During the screening, the phonograph runs synchronously with the picture, so that sound and image appear at the same time.

Baidu Encyclopedia-Thomas Alva Edison