As we all know, Thomas Edison was a great inventor. He obtained 1,093 invention patents in his lifetime. He was the person who obtained the most individual patents since the patent system was implemented. His famous saying "Genius is ninety-nine percent hard work and one percent inspiration" has become a motto that inspires people to work hard. It can be said that Edison's contribution greatly changed human life. Of his many inventions, Edison considered the electric light the most important, but his favorite was the phonograph. The following is the process of the invention of electric light: Lamp is a great invention for mankind to conquer the night. Before the 19th century, people generally used oil lamps, candles, etc. for lighting. Before the advent of electric lights, the most commonly used lighting tools were kerosene lamps or gas lamps. Although this has broken through the night, it has not yet completely liberated mankind from the restrictions of the night. Only the birth of the generator enabled human beings to use various electric lights to brighten the world, turn night into day, expand the scope of human activities, and gain more time to create wealth for society.
Before the advent of electric lights, the most widely used lighting tools were kerosene lamps or gas lamps. This kind of lamp burns kerosene or gas, so it produces strong black smoke and a pungent odor. It is also very inconvenient to add fuel and clean the lampshade frequently. What's more serious is that this kind of lamp can easily cause fire and cause catastrophe. Over the years, many scientists have tried their best to invent an electric light that is both safe and convenient.
In the early 19th century, a British chemist used 2,000 batteries and two carbon rods to make the world's first arc lamp. However, this kind of light is too strong and can only be installed on streets or squares, and ordinary families cannot use it. Countless scientists have been searching hard for this, trying to create a cheap, high-quality, durable household electric light.
The day has finally arrived. On October 21, 1879, an American inventor finally lit the world's first practical electric lamp through long-term repeated experiments. Since then, the name of this inventor, like the electric light he invented, has entered thousands of households. He was Edison, who was praised as the "King of Invention" by later generations.
On February 11, 1847, Edison was born in Milan, Ohio, USA. He only studied in school for three months in his life, but he was studious and diligent in thinking. He invented more than 1,000 inventions such as electric lights, phonographs, and film cameras, and made great contributions to mankind.
When Edison was 12 years old, he was addicted to scientific experiments. Through his tireless self-study and experiments, when he was 16 years old, he invented an automatic telegraph that sent a signal every hour. Later, automatic ticket counting machines were successively invented, the first suitable for typewriters, double and quadruple telegraph machines, automatic telephones and phonographs, etc. Edison was not satisfied with the results of these inventions. In September 1878, Edison decided to launch an attack on the fortress of electric lighting. He read a large number of books on electric lighting and was determined to create electric lights that were cheap, durable, and safe.
He started with incandescent lamps. A small piece of heat-resistant material is placed in a glass bubble. When the current burns it to a white-hot level, it emits light due to heat. He first thought of charcoal, so he put a small piece of charcoal wire into a glass bubble, but it broke immediately as soon as he was powered on.
"What is the cause of this?" Edison picked up the carbon wire broken into two sections and looked at the glass bubble. After a long time, he suddenly remembered, "Oh, maybe because there is air in it, The oxygen in the air assisted the charcoal filament to extinguish, so that it broke immediately!" So he used his handmade air extractor to remove as much air as possible from the glass bubble. As soon as the power is turned on, it does not turn off immediately. But after 8 minutes, the light still went out.
But no matter what, Edison finally discovered: the incandescent lamp is very important in a vacuum state, and the key is the carbon filament. This is the crux of the problem.
So what kind of heat-resistant material should be chosen?
Edison thought about it and decided that platinum has the highest melting point and strong heat resistance! So Edison and his The assistants tried several times with platinum, but this kind of platinum with a higher melting point, although it extended the light-emitting time of the lamp a lot, it still had to be automatically turned off and then automatically illuminated again, which was still very unsatisfactory.
Edison was not discouraged and continued his experimental work. He successively tried various rare metals such as barium, titanium, and indium, but the results were not satisfactory.
After some time, Edison made a summary of the previous experimental work and wrote down all the various heat-resistant materials he could think of. There were as many as 1,600 kinds in total.
Next, he and his assistants classified the 1,600 heat-resistant materials and began testing them. They tried many times, but platinum was still the most suitable. Due to the improved extraction method, the vacuum level in the glass bulb is higher, and the lamp life has been extended to 2 hours. But this kind of lamp made of platinum is too expensive. Who is willing to spend so much money to buy a lamp that can only be used for 2 hours?
The experimental work fell into a trough, and Edison was very worried. Troubled, one cold winter, Edison sat by the fire, looking at the blazing charcoal fire, and couldn't help but murmured to himself: "Charcoal..."
The charcoal strips that can be made from charcoal have been tried. But what should I do? Edison felt hot all over, and he pulled off the scarf around his neck. Seeing the scarf made of cotton yarn, Edison suddenly had a thought in his mind:
Yes! It's made of cotton yarn. The fiber is better than wood. Can this material be used?
He hurriedly pulled off a piece of cotton yarn from the scarf and baked it on the fire for a long time. The cotton yarn turned into charred charcoal. He carefully put the charcoal filament into a glass bubble and tested it, and the result was indeed very good.
Edison was so excited that he made many carbon filaments made of cotton yarn and continued to conduct many experiments. The life of the light bulb was suddenly extended to 13 hours, and later reached 45 hours.
As soon as this news spread, it shocked the whole world. The price of gas stocks in London, England plummeted, and the gas industry was also in chaos. People have a premonition that lighting gas lamps will soon become a thing of the past, and the future will be an era of electric light.
Everyone congratulated Edison, but Edison didn't look happy at all. He shook his head and said, "No, we have to find other information!"
"Why, it stayed on for 45 hours. Not yet?" the assistant asked in surprise. "No! I hope it can last for 1,000 hours, preferably 16,000 hours!" Edison replied.
As we all know, it is good to have more than 1,000 hours of light, but what kind of suitable materials can we find?
Edison already had an idea at this time. Based on the properties of cotton yarn, he decided to look for new materials from plant fibers.
So, the marathon experiment began again. Edison experimented with all the animal materials he could find. He even used horse mane, human hair and beards as filament experiments. Finally, Edison chose bamboo. Before the experiment, he first took out a piece of bamboo, looked at it through a microscope, and jumped up with joy. So, he put the carbonized bamboo filaments into a glass bulb, and when the electricity was turned on, the bamboo filament bulbs lit up continuously for 1,200 hours!
At this time, Edison finally breathed a sigh of relief, and his assistant Everyone wished him well, but he said seriously: "There are many bamboos around the world, and their structures are not the same. We should carefully select them!"
The assistant was deeply impressed by Edison's constantly improving scientific attitude. Excited, they volunteered to go to various places for assessment. After comparison, a kind of bamboo produced in Japan was most suitable, so a large amount of this bamboo was imported from Japan. At the same time, Edison opened a power plant and set up wires. Not long after, the American people began to use this cheap, high-quality, durable bamboo filament light bulb.
When people light up the electric lamp, they often think of this great inventor, who brought endless light to the darkness. In 1979, the United States spent millions of dollars on a year-long commemorative event to commemorate the 100th anniversary of Edison's invention of the electric light.