How does an incandescent lamp work?

The retro light bulb is a beautiful thing, no doubt about it. But how does it all work? How is an Edison light bulb different from a regular light bulb? To be honest, almost nothing. Now let's put everything on the shelves.

First the definition.Incandescent lamp- Light source , in which light is emitted by a spiral, also known as an incandescent filament, also known as a filament body, heated by electric current to high temperature. The most commonly used spiral is made of refractory metal, for example tungsten , or carbon thread. To prevent oxidation of the filament upon contact with air, it is placed in a vacuum, pumping out the air from the glass flask.

Operating principle

Any incandescent lamp, whether ordinary or retro, uses the effect of heating the conductor as it flows through it. electric current. The temperature of the filament increases after the electrical circuit is closed. To obtain visible radiation, it is necessary that the temperature of the emitting body exceed 570 degrees (the temperature at which the red glow begins, visible to the human eye in the dark). For human vision, the optimal, physiologically most convenient, spectral composition of visible light corresponds to radiation with a surface temperature of the solar photosphere of 5770 K. However, no solid substances are known that can withstand the temperature of the solar photosphere without destruction, so the operating temperatures of incandescent lamp filaments lie in the range of 2000-2800 C. The filament bodies of modern incandescent lamps use refractory and relatively inexpensive tungsten ( melting temperature 3410 °C), rhenium and (very rarely) osmium. Therefore, the spectrum of incandescent lamps is shifted to the red part of the spectrum. Only a small fraction of electromagnetic radiation lies in the region of visible light, the bulk comes from infrared radiation and is perceived as heat. The lower the temperature of the filament body, the smaller the proportion energy supplied to the heated wire is converted into useful visible radiation, and the more “red” the radiation seems. Accordingly, retro light bulbs differ from ordinary ones in that the filament heats up less. Due to this, the filament evaporates more slowly and functions longer.

Retro light bulbs, by the way, are also useful. At temperatures of 2200–2900 K typical for incandescent lamps, yellowish light is emitted, different from daylight. In the evening, “warm” (< 3500 K) свет более комфортен для человека и меньше подавляет естественную выработку melatonin, important for the regulation daily cycles body (disruption of its synthesis negatively affects health).

In atmospheric air at high temperatures, tungsten quickly oxidizes, forming a characteristic white coating on the inner surface of the lamp when it loses its seal. For this reason, the tungsten filament body is placed in a sealed flask, from which air is pumped out during the manufacturing process of the lamp. Also found, even more often, are gas-filled lamps: in them the bulb is filled with an inert gas - usually argon High blood pressure in the bulb of gas-filled lamps, it reduces the rate of evaporation of the tungsten filament. This not only increases the life of the lamp, but also allows the body temperature of the filament to increase. Thus, the light Efficiency increases, and the emission spectrum approaches white. The inner surface of the bulb of a gas-filled lamp darkens more slowly when the filament body material is sprayed during operation, like a evacuated lamp. Retro light bulbs are usually made with vacuum bulbs, but some manufacturers make them gas-filled.

Design

Construction of an incandescent lamp. In the diagram: 1 - flask; 2 - flask cavity; 3 - filament (heat body); 4, 5 — electrodes; 6 — thread holder hooks; 7 — lamp leg; 8 - fuse; 9 — base body; 10 — base insulator (glass); 11 - contact with the bottom of the base.

The designs of incandescent lamps are very diverse, but consumer differences are mainly in power, shape and size of the bulb and type of base.

In the design of general-purpose lamps, a fuse is provided - a link made of a ferronickel alloy, welded into the gap of one of the current leads and located outside the lamp bulb - usually in the leg. The purpose of the fuse is to prevent destruction of the bulb when the filament breaks during operation.

Filament

The shapes of filament bodies are very diverse and depend on the functional purpose of the lamps. The filament body of the first lamps was made of coal. In modern lamps they are used almost exclusively spirals from tungsten To reduce the size of the filament body, it is usually given the shape of a spiral. In the case of retro light bulbs, when the artistic effect is important, the spiral is attached as required for the artistic effect, for example, the spiral in Edison's historical light bulbs is imitated. In the case of conventional light bulbs, the spiral is often shaped like a hexagon to ensure uniform illumination.

Base

Base shape with thread of a conventional incandescent lamp was proposed Joseph Wilson Swan or, according to other sources, Lewis Howard Latimer - in the Edison company. The sizes of the socles are standardized. At the lamps household use most common Edison sockets E14, E27 and E40 (the number indicates the outer diameter in mm).

In the USA and Canada, different sockets are used (this is partly due to other voltage in the networks- 110 V, therefore other sizes of sockets prevent accidental screwing in of European lamps designed for a different voltage: E12 (candelabra), E17 (intermediate), E26 (standard or medium), E39 (mogul).

Interesting Facts

"Century Lamp"

• In the USA, one of the fire departments in the city of Livermore (California) has a 60-watt lamp self made, known as the "Century Lamp". It has been continuously burning for over 114 years, since 1901. The unusually long service life of the lamp was ensured mainly by operation at low power (4 Watts), in a deep low-voltage state, with a very low efficiency. Lamp includedGuinness Book of Records in 1972. Photos of this particular light bulb are often published as a “retro light bulb”...
• In the USSR, after the implementation of Lenin’s GOELRO plan, the incandescent lamp received the nickname “Ilyich’s light bulb”. Nowadays, this is most often called a simple incandescent lamp hanging from the ceiling on an electrical cord without a shade.
• To make a regular light bulb, at least 7 metals are required.

The history of incandescent lamps dates back to the nineteenth century. Let's consider the main points associated with this unique invention of mankind.

Peculiarities

An incandescent light bulb is an object that is familiar to many people. Currently, it is difficult to imagine the life of mankind without the use of artificial and electric light. At the same time, rarely does anyone think about what the first lamp looked like, in what historical period it was created.

First, let's look at the design of an incandescent lamp. This electric light source is a conductor with a high melting point, which is located in a bulb. The air has been previously pumped out of it; instead, the flask is filled with an inert gas. Passing through the lamp, the electric current emits a stream of light.

The essence of operation

What is the working principle of an incandescent lamp? It lies in the fact that when electric current flows through the filament body, the element heats up, and the tungsten filament itself heats up. It is she who emits thermal and electromagnetic radiation according to Planck’s law. To create a full-fledged glow, it is necessary to heat the tungsten filament to several hundred degrees. As the temperature decreases, the spectrum becomes red.

The first incandescent lamps had many disadvantages. For example, it was difficult to regulate the temperature, as a result of which the lamps quickly failed.

Technical features

What is the design of a modern incandescent lamp? Since it became the first light source, it has a fairly simple design. The main elements of the lamp are:

• filament body;
• flask;
• current inputs.

Currently, various modifications have been developed; a fuse, which is a link, has been introduced into the lamp. An iron-nickel alloy is used to produce this part. The link is welded into the current input leg in order to prevent the glass bulb from being destroyed when the tungsten filament is heated.

Considering the main advantages and disadvantages of incandescent lamps, we note that since their introduction, lamps have been significantly modernized. For example, thanks to the use of a fuse, the likelihood of rapid destruction of the lamp was reduced.

The main disadvantage of such lighting elements is their high energy consumption. That is why they are now used much less frequently.

How did artificial light sources appear?

The history of incandescent lamps is associated with many inventors. Before the time when the Russian physicist Alexander Lodygin began working on its creation, the first models of incandescent lamps had already been developed. In 1809, the English inventor Delarue developed a model that was equipped with a platinum spiral. The history of incandescent lamps is also connected with the inventor Heinrich Hebel. In the example created by the German, a charred bamboo thread was placed in a vessel from which the air was first pumped out. Goebel has been modernizing his incandescent lamp model for fifteen years. He managed to get a working version of an incandescent light bulb. Lodygin achieved high-quality glow from a carbon rod placed in a glass vessel from which air had been removed.

Practical model option

The first incandescent lamps that could be produced in large quantities appeared in England at the end of the nineteenth century. Joseph Wilson Swan even managed to obtain a patent for his own development.

Speaking about those who invented the incandescent lamp, it is also necessary to dwell on the experiments conducted by Thomas Edison.

He tried to use them as filaments various materials. It was this scientist who proposed a platinum filament as a filament.

This invention of the incandescent lamp marked a new stage in the field of electricity. Initially, Edison's lamps operated only for forty hours, but despite this, they quickly replaced gas lighting.

During the period when Edison was engaged in his research, in Russia Alexander Lodygin managed to create several various types lamps in which refractory metals played the role of filaments.

The history of incandescent lamps indicates that it was the Russian inventor who first began to use refractory metals in the form of an incandescent body.

In addition to tungsten, Lodygin also conducted experiments with molybdenum, twisting it in the form of a spiral.

Specifics of operation of the Lodygin lamp

Modern analogues are characterized by excellent luminous flux, as well as high-quality color rendition. Their efficiency is 15% at the highest glow temperature. Such light sources consume a significant amount of light to operate. electrical energy, therefore their operation lasts no more than 1000 hours. This is more than compensated by the low cost of the lamps, therefore, despite the variety of artificial lighting sources presented on modern market, they are still considered popular and in demand among buyers.

Interesting facts from the history of the incandescent lamp

At the end of the nineteenth century, Didrichson managed to make significant changes to the model proposed by the Russian inventor Lodygin. He completely pumped out the air from it and used several hairs in the lamp at once.

This improvement made it possible to use the lamp even if one of the hairs burned out.

English engineer Joseph Wilson Swan owns a patent confirming his creation of a carbon fiber lamp.

The fiber was located in a rarefied oxygen atmosphere, resulting in brighter and more uniform light.

In the second half of the nineteenth century, Edison, in addition to the lamp itself, invented a rotary household switch.

Large-scale appearance of lamps on the market

Since the end of the nineteenth century, lamps began to appear in which oxides of yttrium, zirconium, thorium, and magnesium were used as filaments.

At the beginning of the last century, Hungarian researchers Sandor Just and Franjo Hanaman received a patent for the use of tungsten filament in incandescent lamps. It was in this country that the first copies of such lamps were manufactured and entered the large-scale market.

In the USA, during the same time period, plants were built and launched for the production of titanium, tungsten, and chromium through electrochemical reduction.

The high cost of tungsten has made adjustments to the speed of introduction of incandescent lamps into everyday life.

In 1910 Coolidge developed new technology production of thin tungsten filaments, which helped reduce the cost of production of artificial incandescent lamps.

The problem of its rapid evaporation was solved by the American scientist Irving Langmuir. It was they who introduced industrial production filling glass flasks with inert gas, which increased the life of the lamp and made them cheaper.

Efficiency

Almost all the energy that is received by the lamp gradually turns into thermal radiation. The efficiency reaches 15 percent at a temperature of 15 percent.

As the temperature increases, the efficiency increases, but this causes a significant reduction in the operating life of the lamp.

At 2700 K, the period of full use of an artificial light source is 1000 hours, and at 3400 K - several hours.

In order to increase the durability of an incandescent lamp, developers propose reducing the supply voltage. Of course, in this case the efficiency will also decrease by about 4-5 times. Engineers use this effect in cases where reliable lighting of minimal brightness is required. For example, this is relevant for evening and night lighting construction sites, flights of stairs.

To do this, carry out serial connection alternating current lamp with a diode, which guarantees the supply of current to the lamp for half of the entire period of current supply.

Considering that the price of a conventional incandescent lamp is significantly less than its average service life, the purchase of such lighting sources can be considered a fairly profitable undertaking.

Conclusion

The history of the appearance of the model of electric lamp that we are accustomed to is associated with the names of many Russian and foreign scientists and inventors. Over the course of two centuries, this artificial lighting source has been subject to transformations and modernization, the purpose of which was to increase the operational life of the device and reduce its cost.

The greatest wear on the filament is observed in the case of sudden voltage supply to the lamp. To solve this problem, inventors began to equip lamps with a variety of devices that ensure their smooth starting.

When cold, tungsten filament has a resistivity that is only twice that of aluminum. To avoid power peaks, designers use thermistors whose resistance drops as the temperature rises.

Low-voltage lamps with equal power have a much higher service life and light output, since they have a larger cross-section of the incandescent body. In luminaires designed for multiple lamps, series connection of several lamps of lower voltage is effective. For example, instead of six 60 W lamps connected in parallel, you can use only three.

Of course, nowadays various models of electric lamps have appeared, which have much more efficient characteristics than conventional light bulbs invented during the time of Lodygin and Edison.

One of the very first electrical sources light became the legendary incandescent lamp. Her patent was accepted in 1879. Since then, this device has been used by mankind in many fields of activity for a long time. However, today the incandescent lamp is gradually becoming a thing of the past. It has been replaced by more economical lighting sources.

There are certain advantages and disadvantages that characterize these devices, as well as their methods of application and varieties that deserve detailed consideration. Also, their comparative characteristics with other lighting devices used today will allow us to draw conclusions about the advisability of using incandescent lamps.

Lamp device

Lamps with characteristics which will be discussed in detail below, used to be found in almost every home. The use of these devices was very simple and convenient. The design of an incandescent lamp is easy to understand. It consists of a glass bulb, inside of which there is a tungsten filament. This container can be filled with gas or vacuum.

The tungsten filament is located on special electrodes through which electricity is supplied to it. These conductors are hidden by the base. It has a thread, making it easy to screw the lamp into the socket. When electricity is supplied through the network through the base, current is supplied to the tungsten filament. It's heating up. At the same time, in environment light is sent. All incandescent lamps work on this principle. There are a huge number of their varieties.

Main characteristics

Certain properties have incandescent lamps. Characteristics These devices are measured using different indicators. The power range of these appliances intended for domestic purposes is from For street lighting and industrial purposes, lamps up to 1000 W can be used.

During operation, the tungsten filament heats up to 3000 °C. Recoil luminous flux it can vary from 9 to 19 Lm/W. In this case, the device can operate at a rated voltage of 220-230 V. Some devices are designed for 127 V network. The frequency is 50 Hz.

The size of the base for such devices can be of 3 types. This is indicated on the labeling. If it is 14 mm, it is. Accordingly, 27 mm is E27, and 40 mm is E40. The larger the base, the greater the power characteristic of the lighting device. It can be threaded, pin, single- or double-pin.

IN normal conditions Incandescent lamps work for about 1 thousand hours.

Varieties

Incandescent lamps, technical characteristics which were discussed above, come in several types. There are several principles by which the presented devices are classified.

First of all, incandescent lamps are distinguished by They can be spherical (the most common), tubular, cylindrical, spherical. There are other, rarer varieties. They are used to create a certain decorative effect(for example, in Christmas tree garlands).

The flask coating can be transparent or matte. There are also mirror varieties. The purpose of the lamp is also quite varied. It can be used for general or local lighting, as well as for special needs (for example, quartz-halogen types).

Volt-ampere characteristics

Is nonlinear. This is because the resistance of the filament depends on temperature and current. In this case, nonlinearity is of an ascending nature. The greater the current, the greater the resistance of the tungsten conductor.

The curve is upward sloping because the dynamic value of the resistance is positive. At any point, the higher the current increase, the more the voltage drops. This contributes to the automatic formation of a stable regime. At a constant voltage, the current cannot be changed due to internal reasons.

Volt-ampere characteristics show that thanks to all the listed laws, an incandescent lamp can be switched on directly to the mains voltage.

Constant power supply

Which allow them to be used for domestic purposes, most often powered by a constant source of electricity. It is also considered to be a resource of unlimited power. Therefore, the mains voltage is often considered the rated voltage of an incandescent lamp.

But it is worth noting that quite often the voltage in the network and its nominal value are slightly different. Therefore, in order to improve performance characteristics illuminators was developed by GOST 2239-79. It enters 5 supply voltage intervals. It must correspond to incandescent lamps used for domestic purposes.

Limited power sources

Incandescent lamps, characteristics which are designed for use in special devices, can be powered from limited sources (battery, accumulator, generator, etc.).

Their average actual voltage does not correspond to the nominal value. Therefore, for incandescent lamps powered by limited current sources, an indicator such as the design voltage is used. It is equal to the average value at which an incandescent lamp can be used.

Marking

To understand what type of lamp is on sale, special markings for these products have been developed. To correctly select the appropriate type of device, you should familiarize yourself with the generally accepted symbols.

For example, argon spiral incandescent lamp 60 W, characteristics which allows it to be used for domestic purposes will be labeled as B235-245-60. The first letter indicates the physical qualities or design features of the product. If there is a second letter in the marking, this is the purpose of the lamp. It can be railway (R), aircraft (SM), switch (KM), automobile (A), searchlight (PZ).

The first digit in the marking indicates voltage and power. The second numerical value is revision. This allows you to choose the right lamp for a particular lighting fixture.

Advantages

Incandescent and LED lamps, comparative characteristics which are compared when purchasing a particular device are quite different. The advantage of devices with tungsten filament is their low cost. There are a number of other features in which incandescent lamps compare favorably with LED and fluorescent light sources.

The presented devices, used previously, operate stably at low temperatures. They are also not afraid of small power surges in the network. This allows them to be used for quite a long time.

If the voltage drops for some reason, the incandescent lamp will still work, albeit with less intensity. Also, such devices are not afraid high humidity. They are easy to connect to the network and do not require any additional equipment.

If an incandescent lamp breaks, hazardous substances will not be released into the air (as happens with energy-saving types of lighting). Therefore they are considered safer.

Flaws

However, quite significant shortcomings contains characteristics of incandescent lamps. Fluorescent lamps , as well as diode varieties lighting fixtures Today it is used much more for several reasons.

First of all, a significant disadvantage of devices with tungsten filament is low level light output. The emission spectrum is dominated by yellow and red shades. This makes the lighting unnatural.

Compared to new lamps, the incandescent principle is characterized by a low operating life. With deviations in the nominal network voltage, it is reduced even more.

The bulb of an incandescent lamp is quite fragile. For this reason, it is most often used with a lampshade. And this further reduces the intensity of lighting indoors.

Incandescent lamps also consume significantly more electricity. Compared to fluorescent LED varieties, this deviation is truly impressive. Therefore, in order to save energy resources, new types of devices should be chosen. This contributes to the gradual cessation of production of incandescent lamps.

This metal is called tungsten. It was discovered in late 1781 by the Swedish chemist Scheele, and was actively studied by scientists throughout the 19th century. Today, humanity knows enough to successfully use tungsten and its compounds in various industries.

Tungsten has a variable valence, which is due to the special arrangement of electrons in atomic orbitals. This metal is usually silvery-white in color and has a characteristic luster. Externally it resembles platinum.

Tungsten can be classified as an unpretentious metal. No alkali will dissolve it. Even strong acids, such as hydrochloric acid, will not affect it. For this reason, electrodes used in galvanization and electrolysis are made from tungsten.

Tungsten and incandescent lamps

Why is the filament in incandescent lamps made from tungsten? It's all about its unique physical properties. The key role here is played by the melting temperature, which is about 3500 degrees Celsius. This is an order of magnitude higher than many metals often used in industry. For example, aluminum melts at 660 degrees.

Electricity, passing through the filament, heats it up to 3000 degrees. Stands out a large number of thermal energy, which is uselessly spent in the surrounding space. Of all the metals known to science, only tungsten is able to withstand such a high temperature and not melt, unlike aluminum. The unpretentiousness of tungsten allows light bulbs to serve in homes for quite a long time. However, after some time the filament breaks and the lamp fails. Why is this happening? The thing is that under the influence of very high temperatures during the passage of current (about 3000 degrees), tungsten begins to evaporate. The thin filament of the lamp becomes even thinner over time until it breaks.

To melt a tungsten sample, electron beam or argon melting is used. Using these methods, you can easily heat metal up to 6000 degrees Celsius.

Production of tungsten

It is quite difficult to obtain a high-quality sample of this metal, but today scientists are coping with this task brilliantly. Several unique technologies have been developed that make it possible to grow tungsten single crystals and huge tungsten crucibles (weighing up to 6 kg). The latter are widely used to produce expensive alloys.

The modern lighting market today is represented not only by a variety of lamps, but also by light sources. Some of the oldest light bulbs of our time are incandescent lamps (ILVs).

Even though there are more advanced light sources today, incandescent lamps are still widely used by people for lighting. various kinds premises. Here we will consider such an important parameter of these lamps as the heating temperature during operation, as well as Colorful temperature.

Features of the light source

Incandescent lamps are the very first source of electric light that was invented by man. These products can have different power (from 5 to 200 W). But the most commonly used models are 60 W.

Note! The biggest disadvantage of incandescent lamps is their high electricity consumption. Because of this, the number of LNs that are actively used as a light source decreases every year.

Before you begin to consider parameters such as heating temperature and color temperature, you need to understand the design features of such lamps, as well as the principle of its operation.
An incandescent lamp, during its operation, converts electrical energy passing through a tungsten filament (spiral) into light and heat.
Today, radiation, according to its physical characteristics, is divided into two types:

Incandescent lamp device

• thermal;
• luminescent.

By thermal, which is typical for incandescent lamps, we mean light radiation. The glow of an incandescent light bulb is based on thermal radiation.
Incandescent lamps consist of:

• glass flask;
• refractory tungsten filament (part of the spiral). Important element the entire lamp, since if the filament is damaged, the light bulb stops glowing;
• base

During the operation of such lamps, the t0 of the filament increases due to the passage of electrical energy in the form of current through it. To avoid rapid burnout of the filament in the spiral, air is pumped out of the flask.
Note! In more advanced models of incandescent lamps, which are halogen bulbs, instead of a vacuum, an inert gas is pumped into the bulb.
The tungsten filament is installed in a spiral, which is fixed to the electrodes. In a spiral, the thread is in the middle. The electrodes to which the spiral and tungsten filament are installed, respectively, are soldered to different elements: one to the metal sleeve of the base, and the second to the metal contact plate.
As a result of this design of the electric light bulb, the current passing through the spiral causes heating (an increase in t0 inside the bulb) of the filament, as it overcomes its resistance.

Working principle of a light bulb

Working incandescent lamp

Heating of the LN during operation occurs due to design features light source. It is precisely because of the strong heating during operation that the operating time of the lamps is significantly reduced, which makes them not so profitable today. In this case, due to heating of the filament, t0 of the flask itself increases.

The operating principle of the LN is based on the conversion of electrical energy that passes through the spiral threads into light radiation. In this case, the temperature of the heated thread can reach 2600-3000 oC.

Note! The melting point for tungsten, from which the spiral threads are made, is 3200-3400 °C. As we can see, normally the heating temperature of the filament cannot lead to the beginning of the melting process.

The spectrum of lamps with this structure differs markedly from the spectrum of daylight. For such a lamp, the spectrum of emitted light will be characterized by a predominance of red and yellow rays.
It is worth noting that the flasks have more modern models LN (halogen) are not evacuated, and also do not contain a spiral thread. Instead, inert gases (argon, nitrogen, krypton, xenon and argon) are pumped into the flask. Such design improvements led to the fact that the heating temperature of the flask during operation decreased somewhat.

Advantages and disadvantages of the light source

Despite the fact that today the light source market is replete with a wide variety of models, incandescent lamps are still quite common on it. Here you can find products for different amounts of W (from 5 to 200 W and above). The most popular light bulbs are from 20 to 60 W, as well as 100 W.

Range of choice

LN continue to be used quite widely because they have their own advantages:

• when turned on, the light ignites almost instantly;
• small dimensions;
• low cost;
• models with only vacuum inside the flask are environmentally friendly products.

It is precisely these advantages that determine the fact that LN are still quite in demand in modern world. In homes and workplaces today you can easily find representatives of these lighting products rated at 60 W and higher.
Note! A large percentage of LN use relates to industry. Often powerful models (200 W) are used here.
But incandescent lamps also have a fairly impressive list of disadvantages, which include:

• the presence of blinding brightness of light emanating from lamps during operation. As a result, the use of special protective screens is required;
• During operation, heating of the filament, as well as the flask itself, is observed. Due to the strong heating of the flask, if even a small amount of water gets on its surface, an explosion is possible. Moreover, heating of the bulb occurs for all light bulbs (at least 60 W, at least lower or higher);

Note! Increasing the heating of the flask still carries a certain degree of danger of injury. Fever glass flask, if touched with unprotected skin, can cause burns. Therefore, such lamps should not be placed in lamps that a child can easily reach. In addition, damage to the glass bulb can cause cuts or other injuries.

Tungsten filament glow

• high electricity consumption;
• if they fail, they cannot be repaired;
• low service life. Incandescent lamps quickly fail due to the fact that when the light is turned on or off, the filament of the spiral can be damaged due to frequent heating.

As you can see, using LN carries many more disadvantages than advantages. The most important disadvantages of incandescent paws are considered to be heating due to the increase in temperature inside the bulb, as well as high energy consumption.

Moreover, this applies to all lamp options with a power from 5 to 60 W and higher.

Important Evaluation Parameters
One of the most important parameters of LN operation is the light coefficient. This parameter has the form of the ratio of the radiation power of the visible spectrum and the power of consumed electricity. For this product this is a fairly small value, which does not exceed 4%. That is, LN is characterized by low light output.

• Other important operating parameters include:
• light flow;
• color t0 or glow color;
• power;

life time.

Let's consider the first two parameters, since we figured out the service life in the previous paragraph.

Luminous flux is a physical quantity that determines the amount of luminous power in a particular stream of light emission. In addition, there is one more important aspect, like light output. It determines for a lamp the ratio of the luminous flux emitted by the lamp to the power it consumes. Luminous output measured in lm/W.

Note! Luminous efficiency is an indicator of the economy and efficiency of light sources.

Table of luminous flux and luminous efficiency of incandescent lamps

As you can see, for our light source the above values ​​are at a low level, which indicates their low efficiency.

Light bulb color

Color temperature (t0) is also an important indicator.
Color t0 is a characteristic of the intensity of light emitted by a light bulb and is a function of the wavelength defined for the optical range. This parameter is measured in kelvins (K).

Color temperature for incandescent lamp

It is worth noting that the color temperature for LN is approximately 2700 K (for light sources with a power of 5 to 60 W and above). Color t0 LN is in the red and thermal tint region of the visible spectrum.
Color t0 fully corresponds to the degree of heating of the tungsten filament, which prevents the FL from quickly failing.

Note! For other light sources (such as LED light bulbs), color temperature does not reflect how warm they are. With an LN heating parameter of 2700 K, the LED will warm up by only 80ºC.

Thus, the greater the power of the LN (from 5 to 60 W and higher), the greater the heating of the tungsten filament and the bulb itself will occur. Accordingly, the greater the color t0 will be. Below is a table to compare efficiency and power consumption different types light bulbs As a control group with which comparison is being made, we took LNs with a power of 20 to 60 and up to 200 W.

Comparative table of powers of different light sources

As you can see, incandescent lamps in this parameter are significantly inferior to other light sources in terms of power consumption.

Lighting technology and glow color

In lighting technology, the most important parameter for a light source is its color t0. Thanks to it, you can determine the color tone and chromaticity of light sources.

Color Temperature Options

The color t0 of light bulbs is determined by the color tone and comes in three types:

• cold (from 5000 to 120000K);
• neutral (from 4000 to 50000K);
• warm (from 1850 to 20000K). It is given by a stearic suppository.

Note! When considering the color temperature of the LN, it should be remembered that it does not coincide with the real thermal temperature of the product, which is felt when you touch it with your hand.

For LN, the color temperature ranges from 2200 to 30000K. Therefore, they can have radiation close to ultraviolet.

Conclusion

For any type of light source, an important evaluation parameter is color temperature. At the same time, for LN it serves as a reflection of the degree of heating of the product during its operation. Such light bulbs are characterized by an increase in heating temperature during operation, which is a clear disadvantage that modern light sources such as LED light bulbs do not have. Therefore, today many people give their preference to fluorescent and LED light bulbs, and incandescent lamps are gradually becoming a thing of the past.