SMD-LEDs: history and main characteristics

LED phenomena by humans were first noticed 90 years ago. This happened in Russia in 1923, when Oleg Losev in the radio technical laboratory of Nizhny Novgorod for the first time observed the glow of silicon carbide. Scientific articles on this subject were published in the 30s of the last century, and the first development appeared only in the 70's. In Leningrad, Zelenograd and Kaluga. Active development of these techniques is associated with orders of the State Traffic Inspectorate for the manufacture of 1000 traffic lights for the 850th anniversary of the capital, in which instead of incandescent lamps , more bright green LEDs were used.

The LED is a crystal-semiconductor attached to an aluminum or copper substrate and designed with an optical system and contact outputs. SMD (surface montage details) LED from other types differs in that the parts in it are mounted directly on the surface. Crystalline structures for this technology are grown by means of organometallic epitaxy. During this process, within one day, the required structures (chips) can be grown on a maximum of 12 substrates.

Further, the crystals obtained are processed with the help of high technologies: they are mounted to the shell, outputs are made, additional substances are applied, heat removal and the necessary focusing are organized. This stage is very expensive, so SMD LEDs are much more expensive than conventional lamps. It is believed that the cost of one lumen, generated by a light-emitting diode, is 100 times higher than the same unit created by a halogen lamp.

The positive characteristics of these systems include low heat, high color purity, lack of infrared and ultraviolet radiation, sufficient strength, durability and safety. Today, the lyrical country of all that produces SMD-LEDs is Japan.

When working with these elements, the following characteristics are usually considered:

- light that can be white (warm or cold), blue, green, yellow or red. White light SMD-LEDs are produced in various ways, including the RGB method, when different colors are mixed with a lens or other optical system;

- country of origin of the chip (usually Taiwan);

- luminous flux (in lumens);

- required voltage;

- the number of crystals (chips);

- the necessary current strength;

- angle of light (from 45 to 140 degrees);

- the presence or absence of a substrate, which is often paid additionally.

SMD-LEDs are widely used for lighting in a variety of areas. They are loved by designers for their high quality of light and electrical safety, employees of the communal sphere - for low energy consumption and high vandal resistance. The only exception to the application of these technologies today is the availability of large areas, so they are not used in production. LED tapes today can be seen in apartments, cafes and offices, including in wet environments, because There are certain types of diodes that are not afraid of water.

The service life of these devices is large enough (up to 50,000 hours for powerful samples), so you can say that SMD-LEDs are the best tool for lighting in the future.