An incandescent lamp is an artificial light source in which light comes from an incandescent body that is heated by an electric current to a high temperature. As a heating body, a spiral made of refractory metal (most often tungsten) or a carbon filament is most often used. To prevent oxidation of the heating body upon contact with air, it is placed in an evacuated flask, or a flask filled with inert gases or halogen vapors.
Two centuries ago, in 1840, the Englishman Delarue produced the world's first incandescent lamp (then it was with a platinum spiral and did not differ in its practicality) ... As they say, the first pancake is lumpy .. but a start has been made ..
Almost 15 years later, in 1854, the German Heinrich Göbel developed the first "modern" lamp at that time: a charred bamboo thread in an evacuated vessel. It then took him another 5 years to develop what many today call the first practical lamp.
In 1860, the English chemist and physicist Joseph Wilson Swan demonstrated the first results of this lamp and received a patent, but difficulties in obtaining a vacuum led to the fact that Swan's lamp did not work long and inefficiently.
In July 1874, the now Russian engineer declared himself. Alexander Nikolaevich Lodygin received a patent for a filament lamp. As a filament, he used a carbon rod placed in an evacuated vessel.+
A year later, Lodygin's lamp was improved. This was done by the scientist Didrichson, he evacuated the air from it and used several hairs in the lamp (in case one of them burned out, the next one turned on automatically).
In the same year, maybe a little later, the Russian electrical engineer Pavel Nikolaevich Yablochkov, working on the "electric candle", discovered that the kaolin, which he used to insulate the coals of the candle, was electrically conductive at high temperature. After which he created the "kaolin lamp", where the "filament" was made of kaolin. A feature of this lamp was that it did not require a vacuum, and the "filament" did not burn out in the open air. However, Yablochkov, with a Russian soul, believed that incandescent lamps were unpromising, and did not believe in the possibility of their use on a large scale.
Yablochkov's "kaolin lamp" was quickly forgotten, but later the German physicist Walter Nernst created a similar lamp, where the "filament" was made of magnesia. But these lamps were not destined to conquer our ceilings. The Nernst lamp also did not require a vacuum, but the essential feature of the "kaolin lamp" and the Nernst lamp is that the "filament" had to be heated to a high temperature in order for the lamp to light up. In the first lamps, the “filament” was heated by a match, later they began to use electric heaters, but this did not allow the lamps to hold out for a long time in the lead.
In 1878, English inventor Joseph Wilson Swan received a British patent for a carbon fiber lamp. In his lamps, the fiber was in a rarefied oxygen atmosphere, which made it possible to obtain very bright light. But this is not yet the lamp that humanity dreamed of.
In the second half of the 1870s, the American inventor Thomas Edison did research work in which he tried various metals as filaments. In 1879 he patents a platinum filament lamp.
In 1880, he returned to carbon fiber again and created a lamp with a lifetime of 40 hours - it was not even bad for that time, although negligible. Interestingly, in selecting the material for the thread, Edison spent, just think about it, about 1500 tests of various materials, and then about 6000 more experiments on the carbonization of various plants. A kind of fan of his work.
By the way, at the same time, Thomas Edison invented the household rotary switch. The kind to say, after.
Still, despite such a short lifespan, Edison lamps are replacing the gas lighting used until then. For some time, the invention even bore the generalized name "Edison-Swan".
In the 1890s, Alexander Nikolaevich Lodygin invented several types of lamps with filaments made of refractory metals. Lodygin suggested using tungsten filaments in lamps (these are the ones used today in light bulbs) and molybdenum and twisting the filament in the form of a spiral. He made the first attempts to pump air out of the lamps, which kept the thread from oxidizing and increased their service life many times over.
By the way, the first American commercial lamp with a tungsten filament was subsequently produced according to Lodygin's patent.
Lodygin also made gas-filled lamps (with carbon filament and nitrogen filling).
Since the late 1890s, lamps with incandescent filaments of magnesium oxide, thorium, zirconium and yttrium have appeared, and a filament of metallic osmium and tantalum has also been used.
At the beginning of the 20th century, in 1904, the Austro-Hungarian specialists Sandor Just and Franjo Hanaman received a patent for the use of tungsten filament in lamps. And in Hungary the first such lamps were produced, which entered the market through one Hungarian company in 1905.
In 1906, Lodygin sold a patent for a tungsten filament to General Electric. In the same 1906, in the USA, he built and put into operation a plant for the electrochemical production of tungsten, chromium and titanium. It must be said that due to the high cost of tungsten, Ladygin's patent finds only limited application.
As we know, progress did not stand still in the 20th century. And in a couple of years, William David Coolidge invents an improved method for the production of a tungsten filament, which subsequently displaces all other types of filaments. Thus, today's light bulb was born.
There remained only the problem with the rapid evaporation of the filament in a vacuum, but it was also solved by an American scientist, a well-known specialist in the field of vacuum technology, Irving Langmuir, who, working since 1909, at General Electric. Langmuir introduced into production the filling of lamp bulbs with inert, more precisely, heavy noble gases (in particular, argon), which significantly increased their operating time and increased light output.
I must say that today the light bulb familiar to us is gradually but surely going to become a thing of the past ..
Today, due to the need to save energy and reduce carbon dioxide emissions into the atmosphere, many countries have introduced or are planning to introduce a ban on the production, purchase and import of incandescent lamps in order to force them to be replaced with energy-saving ones.
An incandescent light bulb is an object familiar to everyone. Electricity and artificial light have long been an integral part of reality for us. But few people think about how the very first and familiar incandescent lamp appeared.
Our article will tell you what an incandescent lamp is, how it works and how it appeared in Russia and around the world.
What is
An incandescent lamp is an electrical version of a light source, the main part of which is a refractory conductor that plays the role of a filament body. The conductor is placed in a glass flask, which inside is pumped with an inert gas or completely devoid of air. By passing an electric current through a refractory type of conductor, this lamp can emit a luminous flux.
The glow of an incandescent lamp
The principle of operation is based on the fact that when an electric current flows through the filament body, this element begins to glow, heating the tungsten filament. As a result, the filament begins to emit radiation of the electromagnetic-thermal type (Planck's law). To create a glow, the temperature of the glow must be a couple of thousand degrees. As the temperature decreases, the glow spectrum will become more and more red.
All the disadvantages of an incandescent lamp lie in the incandescent temperature. The better the luminous flux is needed, the higher the temperature required. At the same time, the tungsten filament is characterized by a filament limit, above which this light source permanently fails.
Note! The temperature limit of heating for incandescent lamps is 3410 ° C.
Design features
Since the incandescent lamp is considered the very first light source, it is quite natural that its design should be quite simple. Especially when compared with current light sources, which are gradually pushing it out of the market.
In an incandescent lamp, the leading elements are:
- lamp bulb;
- glow body;
- current leads.
Note! The first such lamp had just such a structure.
Incandescent lamp design
To date, several variants of incandescent lamps have been developed, but such a structure is typical for the simplest and very first models.
In a standard incandescent bulb, in addition to the elements described above, there is a fuse, which is a link. It is made of ferronickel alloy. It is welded into the gap of one of the two current leads of the product. The link is located in the leg of the current lead. It is necessary in order to prevent the destruction of the glass bulb during the breakthrough of the filament. This is due to the fact that when a tungsten filament breaks through, an electric arc is created. It can melt the remnants of the thread. And its fragments can damage the glass flask and cause a fire.
The fuse destroys the electric arc. Such a ferronickel link is placed in a cavity where the pressure is equal to atmospheric. In this situation, the arc goes out.
Such a structure and principle of operation provided the incandescent lamp with wide distribution around the world, but due to their high energy consumption and short service life, they are now used much less frequently. This is due to the fact that more modern and efficient light sources have appeared.
Discovery history
Researchers from Russia and other countries of the world made their contribution to the creation of the incandescent lamp in the form in which it is known today.
Alexander Lodygin
Until the moment when the inventor Alexander Lodygin from Russia began to work on the development of incandescent lamps, some important events should be noted in its history:
- in 1809, the famous inventor Delarue from England created his first incandescent lamp equipped with a platinum spiral;
- almost 30 years later, in 1938, the Belgian inventor Jobar developed a carbon model of an incandescent lamp;
- Inventor Heinrich Goebel from Germany in 1854 already presented the first version of a working light source.
The German-style light bulb had a charred bamboo filament that was placed in an evacuated vessel. Over the next five years, Heinrich Goebel continued his developments and eventually came to the first prototype of a working incandescent light bulb.
First practical light bulb
Joseph Wilson Swan, the famous physicist and chemist from England, in 1860 showed the world his first successes in the development of a light source and was rewarded with a patent for his results. But some of the difficulties that arose with the creation of a vacuum showed the inefficient and not long-term operation of the Swan lamp.
In Russia, as noted above, Alexander Lodygin was engaged in research in the field of efficient light sources. In Russia, he was able to achieve a glow in a glass vessel of a carbon rod, from which the air had previously been pumped out. In Russia, the history of the discovery of the incandescent light bulb began in 1872. It was in this year that Alexander Lodygin succeeded in his experiments with a carbon rod. Two years later, in Russia, he receives a patent under the number 1619, which was issued to him for a filament type of lamp. He replaced the thread with a rod of coal, which was in a vacuum flask.
Exactly one year later, V. F. Didrikhson significantly improved the appearance of the incandescent lamp created in Russia by Lodygin. The improvement consisted in replacing the carbon rod with several hairs.
Note! In a situation where one of them burned out, the other automatically turned on.
Joseph Wilson Swan, who continued his attempts to improve the already existing model of the light source, receives a patent for light bulbs. Here, carbon fiber acted as a heating element. But here it was located already in a rarefied atmosphere of oxygen. Such an atmosphere made it possible to obtain very bright light.
Contribution of Thomas Edison
In the 1970s, an inventor from America, Thomas Edison, joined the inventive race to create a working model of an incandescent lamp.
Thomas Edison
He conducted research on the use of filaments made from various materials as an incandescent element. Edison in 1879 receives a patent for a light bulb equipped with a platinum filament. But a year later, he returns to the already proven carbon fiber and creates a light source with a lifespan of 40 hours.
Note! Simultaneously with the work on creating an efficient light source, Thomas Edison created a rotary type of household switch.
Despite the fact that Edison bulbs work only 40 hours, they began to actively force out the old version of gas lighting from the market.
The results of the work of Alexander Lodygin
While Thomas Edison was conducting his experiments on the other side of the world, Alexander Lodygin continued to do similar research in Russia. In the 90s of the 19th century, he invented several types of light bulbs at once, the threads of which were made of refractory metals.
Note! It was Lodygin who first decided to use a tungsten filament as an incandescent body.
Bulb Lodygin
In addition to tungsten, he also proposed using filaments made of molybdenum, as well as twisting them into a spiral. Lodygin placed such threads of his in flasks, from which all the air was pumped out. As a result of such actions, the threads were protected from oxygen oxidation, which made the service life of the products much longer.
The first type of commercial light bulb produced in America contained a tungsten filament and was made according to Lodygin's patent.
It is also worth noting that Lodygin developed gas-filled lamps containing carbon filaments and filled with nitrogen.
Thus, the authorship of the first incandescent light bulb sent into serial production belongs to the Russian researcher Alexander Lodygin.
Features of the Lodygin light bulb
Modern incandescent lamps, which are direct descendants of Alexander Lodygin's model, are characterized by:
- excellent luminous flux;
- excellent color reproduction;
Incandescent lamp color rendering
- low rate of convection and heat conduction;
- filament filament temperature - 3400 K;
- at the maximum level of the glow temperature indicator, the coefficient for efficiency is 15%.
In addition, this type of light source consumes a lot of electricity during its operation, compared to other modern light bulbs. Due to the design features, such lamps can operate for approximately 1000 hours.
But, despite the fact that, according to many evaluation criteria, these products are inferior to more advanced modern light sources, due to their low cost, they still remain relevant.
Conclusion
Inventors from different countries participated in the creation of an efficient incandescent lamp. But only the Russian scientist Alexander Lodygin was able to create the most optimal option, which we, in fact, continue to use to this day.
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Guess how long an incandescent lamp can last?
It is well known that incandescent lamps burn out rather quickly. But, as it turned out, there is at least one such lamp that has already worked for more than 100 (more precisely, 115) years. It is located in Livermore (USA, California) at the station of the local fire service. It was there that this long-lived light bulb was turned on in the summer of 1901 and has been operating almost continuously since then. Now it is listed in the Guinness Book as the most durable incandescent lamp. Before that, specialists from General Electric conducted a special technical audit, which confirmed that this is exactly the light bulb that was turned on 115 years ago. 
Such a high durability of the “centenary”, or as it was also called, the “Livermore” lamp contributes to its mode of operation: it burns almost continuously, the number of on / off is minimal (for 100 years it was turned off only a few times) at reduced power (4 W), with a very strong "undershoot", and, accordingly, with an extremely low efficiency. This lamp is used for night (duty) lighting. During the service, it was reconnected to new places several times. The latest such reconnection was made in 1976. Then the Livermore lamp was turned off for 22 minutes.
It is not known how long this century-old lamp will last, but after it does burn out, the Livermore Lamp will be placed in the Ripley Museum.
Modern light sources
Energy saving programs involve the replacement of luminaires with traditional light sources, such as the Livermore lamp, with LED, and LED panels are ideally suited to solve such problems in the field of indoor lighting. Light-emitting diode panels (LED panels) are applied to illumination of household, administration and office, trade, entertaining and industrial premises. It should be said that ice panels are currently used to a greater extent for commercial and office buildings, but they fit perfectly into the modern interior of residential premises. In addition, buying LED panels in Ukraine is quite easy, for this, all you need to do is go to the Power of Light online store.
Judgment on electricity
At the dawn of electrification, the advantage of electric lighting was not as obvious as it seems to us now, from the height of almost a century and a half of experience. In addition, economic interests intervened. The massive replacement of gas lighting fixtures with electric ones threatened with serious losses (and even ruin) for British gas companies, which unleashed a real information war against electric lighting. 
In 1879, the British Parliament decided to establish a special commission, which was supposed to deal with the huge flow of true and false information and make a verdict on the prospects for the development of the lighting industry using electricity. This commission was given the most serious powers. The appearance of a witness summoned to the meeting of this commission, as well as the giving of truthful testimony by him, were also obligatory, as if it were a question of a summons to court. The work of the commission itself was also built on the model of the court. But the defendant was extremely unusual - a natural phenomenon known collectively as "electricity".
Members of the commission sat in judges' places, witnesses for the "charge" and "defence" gave their testimony and answered questions, and the entire course of the meetings was carefully recorded in shorthand. As material evidence, a fair amount of various electrical appliances were presented, the work of which was demonstrated here. Also, the commission was presented with a lot of drawings, graphs, diagrams, etc. for consideration.
The arguments of the witnesses of the “accusation”, that is, opponents of electric lighting, boiled down mainly to the fact that electric light is “cold, insensitive and dead” (as one artist said), “it distorts colors, so it is difficult to choose clothes with it, and besides, when under electric lighting, the face seems paler than it actually is ”(opinion of one lady). Vendors at the newly electrified Billingsat Market claimed that the electric lights made fish lose their marketability and their sales fell. In addition, almost all opponents of electrification complained about the annoying flashing of lighting electrical appliances and the sensation of pain in their eyes caused by them.
Supporters of electrification, they are also "witnesses to the protection of electricity" explained that you should not look at the included lamps, just as no one looks directly at the sun on a fine day. The “flashing” effect was due to a technical defect, well-made electric lights shone evenly (and this was demonstrated). As for the distortion of color perception, the traditional for that period candles and gas lanterns distorted colors even more, and the effect of “pale deadness” of the skin of the face, hated by ladies, was observed only if the room (space) was illuminated by a gas and electric lantern at the same time.
The commission sat for a long time, but then issued a final verdict. It was decided that the existing knowledge about the laws of electricity and the development of electrical engineering had reached a level sufficient for mass production and the introduction of electrical appliances. Electric lighting was given the opportunity to compete with gas and other traditional types of it (candle, kerosene, etc.). A special clause of the resolution was forbidden to involve gas companies in the organization of electric lighting, since they are "absolutely incompetent in the field of electrical engineering."
Power record holders
The absolute superiority in the power of continuously emitted light is held by an arc lamp filled under pressure with an inert gas - argon. It consumes 313 kW of electricity and emits a luminous flux of 1.2 megacandela. This lamp was manufactured in 1984 by the Canadian company Vortek Industries. 
Of the serial products, the most powerful lighting fixture in history was the searchlight, which was produced for military purposes from 1939 to 1945 by the General Electric Company. Its design was developed at the Hearst Research Center (Great Britain, London). This spotlight consumed 600 kW of electricity. Its arc brightness reached 46,500 cd/sq. see. The parabolic reflector had a diameter of 3.04 m. As a result, a beam of light was created with an intensity of 2.7 megacandelas.
Durability vs Efficiency
When incandescent lamps were first invented, many experiments and studies were carried out with them. It was during this period that it was possible to establish that the maximum possible efficiency (here: the percentage of the energy of the emitted light of the visible spectrum to the electricity consumed) is 15% and is achieved at an incandescent filament temperature of 3400K. However, the resource of such lamps was only a few hours, and all attempts to increase it were unsuccessful. However, if the filament is heated to “only” 2700K, the lamp life is approximately 1000 hours. True, its efficiency is reduced to 5%.
It was these lamps that were mass-produced for over 100 years. They are still in use today. Only 5% of the electricity consumed is converted into light radiation. The remaining 25% of the energy is released as heat. So, it is more correct to call incandescent lamps not a “lighting”, but a “heating” device.
The dependence of the brightness of the lamp burning on the magnitude of the voltage
Previously, on the territory of the Russian Federation, the standard voltage for household networks was 220 V. But in 2005, a new GOST was adopted and now the voltage of 230V is considered standard. Moreover, a 10% deviation from the nominal value in any direction is considered acceptable. That is, in a specific household outlet and a specific point in time, the voltage can be from 207 to 253V, and this will be considered normal. The former standard rating of 220V is included in this range, so there was no need for a mass replacement of electrical equipment.
An experiment was carried out to measure the luminous flux emitted by an incandescent lamp at various voltage values, which were set by means of LATR. For the experiment, we took a matte lamp 230V 60W Osram CLAS A FR60 230V E27. According to the information on the packaging, it provides a light output of 710lm. The results of measurements of real luminosity, at various voltages possible in the network (207 - 253V) turned out to be quite remarkable.
With a deviation of the real voltage from the nominal value by 10% (we remind you that such a deviation is considered acceptable) to either side, the brightness of the glow of this lamp changed by at least 30%. So at the lowest of the allowable voltage values of 207V, this nominally 60-watt lamp shone like a 40-watt lamp. True, even at a voltage strictly corresponding to the nominal value of 230V, the lamp did not develop a light flux intensity of 710 Lm., Which were stated in its parameters. And it's still a lamp from the world leader in this industry, "OSRAM". There is reason to believe that with lamps from other manufacturers, including domestic ones, the situation is even sadder.
Note that modern LED lamps are not subject to such a dependence on mains voltage. Even with very serious voltage drops (including those considered “emergency”), LED lamps continue to shine the same way. The device of such lamps necessarily implies the presence of a power driver, which just performs the functions of a "stabilizer".
Before the invention of the electric light source, people illuminated the premises with wax candles, oil lamps, and kerosene lamps. We present interesting facts about the incandescent lamp.
History of creation
Light bulbs were created separately by two inventors - Alexander Lodygin, a native of Russia, and Thomas Edison from the USA. Both scientists made great breakthroughs and contributions to electrical engineering.
In 1872, Lodygin placed a carbon rod in a glass vessel from which he had previously evacuated the air. In 1874 the inventor received a patent for his charcoal lamp. Later, Lodygin proposed to replace the carbon rod with a tungsten one. The thread of this material is still used in modern lamps.
Thomas Edison worked for a very long time to create a lamp that could be used for a long time, and in 1878 he succeeded. In his first light bulb, charred shavings obtained from Japanese bamboo were used. The inventor also created the base and cartridge used in the light bulb.
In the production of tungsten filament in light bulbs, they began to be widely used at the beginning of the 20th century - in 1909. And after a few years, the light bulbs began to be filled with gases - nitrogen, krypton or argon, and the thread acquired a modern look - spiral.
Modern incandescent lamp
In modern light bulbs, a tungsten filament is mainly used as a filament. An electric current passes through the thread, it heats up to 2500 ° C and emits light very close to daylight.
Protection from the effects of atmospheric air is carried out by a glass flask. The base is made of lead glass, and the flask is made of lime. At the moment, most of the lamps are filled with inert gases, with the exception of low-power bulbs (25 W), from which air is pumped out (vacuum).
One of the parts of the lamp - the base - is a kind of conductor between the network and the light bulb. Thanks to him, the lamp is mounted in the cartridge. The external elements of the cartridge are contacts, and the internal elements are electrodes (current inputs).
The flask of different lamps has a different shape: pear-shaped, ovoid, reflex, candle-shaped. Also, incandescent lamps differ in power and application.
Some physical features
The incandescent lamp itself is no longer a source of light, but a source of heat. The efficiency of the lamp is only 5 percent, the remaining 95 goes to the thermal effect. The life of the lamp is about a thousand hours.
Prior to the change in GOST until 2005, the Russian Federation used the 220 V mains voltage standard. Since 2005, the mains voltage has become 230 with a margin of error of 10 percent, i. the norm of voltage in networks is from 207 V to 253 V. One of the important characteristics of incandescent lamps is the luminous flux. Unlike LED lamps, incandescent lamps are very dependent on the mains voltage.
During the experiment with the German Osram bulb, the value of the luminous flux of which is 710 lm at parameters of 230 V and 60 W, it was found that the dependence of the luminous flux on voltage was enormous! Measurements at a voltage of 207 V showed 416 Lm, and at 253 V - 890 Lm. The experiment also showed not only a large spread, but also the fact that the lamp does not fall into its characteristics: at 230 V, the luminous flux was less and amounted to 628 Lm, and only at 237 V did it reach its declared number - 710 Lm.
The oldest lamp
In the American city of Livermore, California, there is the oldest light bulb, which is 118 years old. They turned it on back in 1901 at the fire station and it works virtually continuously. This bulb was listed in the Guinness Book of Records as the most durable. It was made in the late 90s of the 19th century.
She herself is low-power, with a power of 4 watts, has a very low efficiency and is very pale (has a deep undershot). Nevertheless, the light bulb was turned off a couple of times - because of its “moves” to another street (1901, 1903 and 1976), the reconstruction of the building (1937) and power outages (30-70s of the XX century). Since the last move in 1976, the lamp has never gone out.
The light bulb has gained fame not only for itself, but also for its city - thousands of people come on an excursion to look at the centenarian. In 2001, celebrations were held to mark the centenary of the lamp. When the light goes out, they will not throw it away, but will give it to the museum.
To everyone who knew, but forgot, and to those
who wants to satisfy children's interest,
dedicated.
Remember how as a child they ran around the apartment to their parents with questions: what kind of thread in the lamp burned out? And in general, how can that burnt thread glow? Why is it that if you put a lamp in your mouth, you can't get it out without a doctor? Why is the lamp round like a pear? And whose lamp is it, which Ilyich?
And now we have grown up and forgot about all these questions. Let's try to figure it out without mournful scientific terms and super-boring theory.
You enter the store, eyes widen from the number of various lamps on the shelves. So who is the author of this invention? In fact, more than one generation of scientists have worked to create lighting in our homes.
In any historical facts, over time, inaccuracies appear, or they are deliberately turned over. Believe me, the creation of the lamp was no exception. Much is far-fetched, much is an attempt to pull the blanket over to one's side. I will not describe all those who at various times worked on the creation of the lamp. Let's dwell on the most basic milestones of development. Due to the discrepancy between the facts in the huge number of sources studied, I will indicate the time period somewhere in order to avoid mistakes.
It all started back in 1802, when experiments were carried out in the Russian Empire on such a physical phenomenon as an electric arc. Conducted these experiments scientist Vasily Petrov. The result was the creation of an arc lamp based on carbon electrodes.
By the beginning of the second decade of the nineteenth century, Humphrey Davy, an English scientist, had carried out very similar experiments. Later it turns out that both, Petrov and Davy, wrote scientific articles that described the possibility of using electric current in lighting.
The next round is considered to be the creation of the lamp by the famous astronomer and corresponding member of the St. Petersburg Academy of Sciences - Warren De La Rue. His lamp looked like a tube with a platinum coil. Air was evacuated from the tube as much as possible. Even then it was believed that in a vacuum, light diverges better, and the light source does not oxidize. The generally accepted version is that this lamp was introduced in 1820, but this is not so. Warren De La Rue was born in 1815, and it turns out that he invented the lamp at the age of 5. This is how facts get distorted over time. In fact, the lamp was created in 1840.
Next, we will try to lift the veil of secrecy over who first invented the image of a modern lamp - Lodygin or Edison? Actually Lodygin. But not everything is so clear. In 1872, the first sample of a lamp similar to the modern one appeared. It looked like a ball with evacuated air, in which a thread was placed between the conductors. Yes, you heard right, this was the progenitor of the incandescent lamp, although at that time the filament was carbon. The inventor received a patent number 1619 only two years later, on July 11, 1874. Then, for the first time, a filament incandescent lamp was patented, and the great Russian engineer Alexander Nikolaevich Lodygin did it. About a year later, V. F. Didrikhson improved the lamp by adding a few more filaments to it, in the event of a burnout of one, the next one automatically turned on.
But then Thomas Edison came into play. He spent an astronomical sum of $100,000 at the time, and tried over six thousand thread materials before returning to charred bamboo fiber. He made not much more than two dozen lamps. But they were unrealistically expensive to manufacture. Later, he used a cotton-based thread placed between platinum electrodes. These were very short-lived and expensive lamps, but this did not prevent them from selling successfully for the next few decades.
Simultaneously with Edison's research, Alexander Nikolaevich Lodygin continued to work on improving the lamp. Lodygin studied lamps with a thread of refractory materials for a long time. He received several more patents for lamps of various shapes and principles of operation. But events occurred that forced Alexander Nikolaevich to leave his homeland for as long as 23 years. In 1884, mass arrests and executions of people involved in the revolutionary movement began, including many friends of our engineer, and this was the reason for his departure. In the same year, in Paris, where he left, the production of lamps was organized. The inventor was worried that he would not be able to personally participate in the Third Electrical Exhibition in St. Petersburg, but he nevertheless sent a batch of lamps to the exhibition. In 1893, he began to produce lamps with a brightness of "100-400 candles", and a year later he opened a company for the production of lamps "Lodygin and de Lisle". In 1906, Lodygin sold the patent to a US company, General Electric. Alexander Nikolayevich himself moved to the USA and continued to study refractory metals, and in the same year he opened a titanium, chromium and tungsten processing plant in America, which became the main supplier of tungsten for incandescent lamps. By the way, there is another little-known fact: induction furnaces and resistance furnaces, which melted metal at his factory, he invented himself.
Since the sale of the patent to General Electric, it began to develop the production of lamps. After some time, the company's engineers made the lamp the way we see it today. In Russia, an incandescent lamp appeared in every house after the electrification of the entire country was carried out according to the plan of Vladimir Ilyich Lenin. Hence the name - Ilyich's Lamp.
The answer to the question: why is the lamp round, is actually simple. It's just that the flask is equidistant from the hot filament, so as not to overheat on one side and not burst. In addition, such a shape excludes as much as possible the precipitation of tungsten evaporation products on one side. The thread is very thin, so any sudden movement can break the thread. The flask is filled with an inert gas to minimize oxidation and filament breakage. There are 2 wires inside the base, one is the input of electricity from the base (from the thread), and the second is under the base, the current output from the lamp isolated from it. The base is of this shape simply because it is easier to replace the lamp.
The last question remains: why can't you get a lamp that a child (or maybe not a child) put in his mouth without a doctor? Actually it is elementary. It's just that the muscles of the oral cavity are designed in such a way that the mouth can open to the maximum width only after it is completely closed, otherwise a muscle spasm occurs. And here the doctors will either open the mouth to the end with a special device, or give a relaxing injection. Do not try to verify the validity of the statement on yourself, it can be dangerous.
I hope you had a good time, see you on the pages of our blog!
