Kinds and types of light-emitting diodes: classification, characteristics, purpose

LEDs are becoming more and more popular solutions, and in many different areas. They can be used as decorative products or for lighting purposes, as well as for various areas outside the buildings. LEDs are delivered to the market in a fairly wide range of modifications. At the same time, the developers of the respective products periodically offer innovative solutions, which in the future are able to form new market niches. What are the most common types of LEDs today? For what purposes can they be used?

What are LEDs?

Before considering common types of LEDs, we will study general information about the corresponding devices. The LED is a semiconductor that is able to convert an electric current into light. In this case, the semiconductor crystal, which is its main component, consists of several layers characterized by two types of conductivity. Namely - hole and electronic.

Conductivity of the first type implies the transition of an electron from one atom to another, on which there is free space. In turn, another electron arrives at the first atom, another electron, etc. This mechanism acts due to the covalent bonds between the atoms. At the same time, they do not move. As a matter of fact, a positive charge is moving, which physically is called a hole. In this case, during the transition of an electron to holes, light is released.

The structure of the LED in general is similar to a rectifier diode. That is, it has 2 outputs - the anode and the cathode. This feature predetermines the need to observe polarity when connecting the LED to an electrical power source.

The corresponding products are calculated in the general case for a direct current of 20 milliamps. In principle, this value can be reduced, however, in this case, the color may change and the brightness of the LED may decrease. In turn, it is undesirable to increase the corresponding parameter. If the current exceeds the optimum value, then in order to reduce it to the required level, a limiting resistor is applied.

There are quite a few nuances that should be borne in mind when installing LEDs. This is predetermined by their internal structure, form of execution. In some cases, it may be necessary to use a stabilizer for LEDs and other electronic components to ensure the functioning of the device in which the product in question is being installed.

Depending on the composition of semiconductors in the LED, it can be red, yellow, green or blue. For example, if the structure of the corresponding electronic component contains gallium nitride, then the LED will glow blue. Actually, one of the criteria, based on which these or other types of LEDs are allocated, can be their color.

Application

The first light-emitting diodes delivered on the market, were issued in cases from metal. Gradually, it began to replace plastic. In this case, according to color, it is usually chosen taking into account the color of the LED's emission. However, transparent plastic enclosures are also quite common.

The considered electronic devices find wide application in the most different spheres. This is due to the fact that almost all types of LEDs are characterized by:

- energy efficiency;

- long service life;

- the ability to determine the color of the glow, as well as to regulate its power;

- security;

- ecological compatibility.

If we talk about energy efficiency, LEDs with the same light output can have significantly less power than conventional lamps. The smaller power LEDs at the same time reduces the overall load on the energy system of the building. The service life of devices can be several tens of times higher than what characterizes ordinary lamps. In this case, in terms of functions, LEDs can not be inferior to them at all.

As the mass demand for these products is formed, as well as their cheaper prices, LEDs are increasingly being used for the same purposes as conventional lamps. There are no difficulties in installing the corresponding solutions in comparison with traditional lighting devices. It is important only to make sure whether a particular LED is suitable for installation in the grid. To do this, it may be necessary in advance - before buying LEDs - to reveal its main parameters.

What other advantages can the considered solutions have?

So, it can be noted that the color temperature of the LED can be almost any - including when combining the above colors. In addition, the devices can be supplemented with different light filters that can significantly expand the scope of application of LEDs in terms of selecting the required color temperature.

The ability to control the luminescence power is another advantage of the devices under consideration. This option is perfectly combined with their high energy efficiency. The power of the LED can be adjusted in automatic mode - based on the actual conditions of use of lighting devices. And it practically does not affect their service life.

LEDs are environmentally friendly, since they do not emit harmful radiation for humans. This feature, again, extends the possibilities of using the devices under consideration.

Classification: indicator and lighting solutions

Experts identify 2 main categories of LEDs - indicator lights, as well as lighting. The first are mainly designed to create a decorative light effect and are used as an element of decorating a building, room, vehicle. Or as a tool for text styling - for example, on an advertising banner.

In turn, there are lighting LEDs. They are designed to increase the brightness of lighting in a room or in a certain area of the territory - for example, if we consider LEDs for cars. Appropriate type of solutions are an alternative to the use of conventional lamps and in many cases more profitable in terms of energy efficiency and environmental friendliness.

Types of execution

But back to the classification of LEDs. You can determine the widest range of grounds for their classification as one or another category. The widely used in the expert environment involves the allocation of the following main types of LEDs:

- DIP;

- Spider LED;

- SMD;

- COB;

- Fiber;

- Filament.

Let us consider them in more detail.

What is the specificity of DIP-LEDs?

If we study in more detail how these types of LEDs appeared on the market, then devices of the DIP class can be attributed to the first, which began to be sold massively. These solutions are crystals that are housed in cases with optical components, in particular a lens that creates a light beam.

It can be noted that the category of light-emitting diodes in question, despite the general prevalence, is rarely used in the high-tech sphere. Most often, these solutions are used as components of light advertising, tapes, highlights, ornaments.

LEDs DIP are classified as indicator. They have one more name - DIL. They are installed on the board, on which you first need to make holes. It can be noted that different types of light-emitting diodes can be distinguished in the category under consideration, which differ in diameter of the bulb, color, material of manufacture. In this case, the corresponding parameters can be represented in the widest spectrum. In form, the solutions under consideration are cylindrical. Among the corresponding LEDs are both monochrome and multicolor devices.

Spider LED

This type of LEDs in general are very similar to the previous devices. But they have twice as many leads - 4. While the DIP LEDs - 2. The fact that the type of solutions presented has more outputs, optimizes the heat sink and increases the reliability of the corresponding components. In practice, they are used in various areas, in particular as LEDs for cars.

SMD type LEDs

These solutions are manufactured using the concept of surface mounting. That is, they are LEDs that are installed on any surface, while other solutions can be installed through through-wiring.

Dimensions of LEDs of this type can be significantly smaller than those of alternative solutions, as well as those structures for which they are installed. Again, in this case it is legitimate to talk about a more optimal heat sink. The use of LEDs such as SMD in many cases makes it possible to extend the variability of the design of lighting structures.

SMD-LEDs belong to the category of lighting. Characterized by a rather complex structure. So, the LED itself consists of a metal substrate. It fixes the crystal, which is soldered directly to the contacts of the substrate body. A lens is placed above the crystal. In this case, 1-3 LEDs can be installed on one substrate. SMDs include common types of ultra-bright LEDs, such as 3528. These solutions have a high level of demand.

COB-type LEDs

The next popular type of LED is COB. It is made with the use of technology, which involves the installation of the crystal directly on the board. This solution is characterized by a large number of advantages:

- the protection of the compound from oxidation;

- small dimensions of the structure;

- Heat sink efficiency;

- Reducing the cost of installing LEDs - in comparison, in particular, with devices such as SMD.

If we consider the above types of LEDs, it can be noted that the solutions of the COB brand can be attributed to the most innovative. This technology was first realized by Japanese engineers in the late 2000s. Now these types of LEDs continue to gain popularity.

According to experts, the solutions under consideration may even become the most in demand at the market, especially if we talk about the commercial segment, the sphere of household lighting. It is worth noting that there are areas within which the use of COB LEDs can be difficult. Among them - the production of professional lighting equipment. The fact is that the LEDs under consideration are not very optimal from the point of view of adapting to the organization of lighting with the established light intensity curve. In such cases, devices like SMD may be more suitable.

The described diodes refer to lighting. As experts note, they can be attributed to the best, based on the characteristics of the light flux. Supplied on the market in different colors, for example red, green, blue, and also white. The luminous flux of these models has a scattering angle of 40-120 degrees.

More than 9 COB-type LEDs can be installed on one substrate. They are covered with a phosphor, due to which they acquire a high luminosity. It can be noted that the luminous flux of these solutions is higher than that of devices of the SMD type. Thus, if we consider what type of LEDs are better, then according to the specified criterion an advantage can be a solution of the COB class.

LEDs such as COB also find application in the automotive industry. They can be used as a component of the front, taillights, turn signals. The main thing is to properly install the purchased devices. For this it makes sense to turn to experienced specialists.

Fiber LEDs

To the innovative can be attributed fiber LEDs. They appeared on the market recently, in 2015. Developed were the solutions considered by engineers from South Korea.

Use these types of LEDs can be in the production of clothing. That is, it is quite realistic to sew a shirt or T-shirt that can shine. Manufacture of clothes based on fiber LEDs also involves the use of various polymers, as well as aluminum compounds.

LEDs Filament

Another example of innovative LEDs - solutions like Filament. Their main advantage is high energy efficiency. With the same power, for example, with LEDs such as COB, Filament solutions can provide a higher level of illumination.

The innovative product in question is most often used in the manufacture of lighting lamps. Among the remarkable characteristics of the production of the corresponding LEDs is the installation directly on a substrate made of glass. This approach makes it possible to propagate the light emitted by the LED by 360 degrees.

How to choose the best option?

How to determine the type of LED, which is optimal for a particular design? There are a large number of criteria that can be used in this matter. In principle, it is quite legitimate to determine the scope of the LED based on its classification by the features that we have discussed above. Let's study the specificity of the choice of the corresponding electronic components taking into account the features of the devices:

- DIP;

- SMD;

- COB.

Selection of LEDs: DIP solutions

As we noted above, DIP-LEDs are among the earliest products that have appeared on the market. Thus, they involve quite old, but still in demand technologies. Their main advantages are simple installation, convenient form, low power consumption, low heating, and also a sufficiently high degree of protection from external influences.

Most often, the LEDs under consideration are available in diameters of 3 and 5 mm. If we compare LEDs by types, we can conclude that the solutions in question are the most optimal for use:

- as elements of car tuning;

- as decorative components;

- as part of low-power - as a variant of self-made - lanterns.

The LEDs under consideration have relatively low cost and availability in the market. It can be noted that among the most frequently encountered modifications are 12-volt LEDs. They can be present in various online catalogs, as well as specialized stores in a wide range. Actually, any 12 volts LEDs are characterized by a high demand in the market.

Selection of LEDs: features of solutions such as SMD

The corresponding type of solutions in appearance differ fundamentally from the others in that they have a planar shape. Installation of these electronic components is carried out without the use of legs. The current to the SMD type LEDs is applied to the terminals, which are located on their back side.

Thus, the installation of these devices is done without the use of holes. Placement of LEDs can be carried out very compactly. As a result, the design on which the corresponding devices are located may also decrease.

The main methods of application of the devices under consideration are the same auto tuning, various types of interior lighting. Among the most significant advantages of these options are high brightness, light output. In combination with small sizes, these solutions have significant advantages over alternative models of products.

Among the most common in the modern market - the type of LED 3528. These products are widely used in the production of LED strips. The design of the respective products allows the production of three-color LEDs - with red, blue, and green glow colors. On the basis of solutions of type 3528, many other electronic components are manufactured, for example, an LED like SMD 5050.

The products in question are also characterized by price accessibility. Presented on the market, they are usually in a wide range.

Selection of LEDs: features of COB solutions

First of all, it should be noted that a significant part of the LEDs of the corresponding type are very powerful structures. Their characteristic feature is the rapid dispersion of light, due to the placement of crystals on the surface, which provides dynamic heat removal.

The LEDs under consideration are very bright. This makes them in demand just for use in the design of automobile headlights. It should be noted that these products should be installed taking into account a number of significant nuances - these can be known only by experienced specialists. Therefore, to install the appropriate solutions it is recommended to contact the competent service.