Principles of construction of high-power LEDs. Scheme, description

ENCYCLOPEDIA OF RADIO ELECTRONICS AND ELECTRICAL ENGINEERING
Free library / Electrician

LEDs. Principles of construction of high-power LEDs. Encyclopedia of radio electronics and electrical engineering

Free technical library

Encyclopedia of radio electronics and electrical engineering / LEDs

Power LED designs are based on the following principles:

Highly efficient emitting heterostructures were used in AlGalnP/GaAs systems. AlGalnP/GaP and InGaN (the active region of the heterostructure contains either a single or multiple quantum wells);
emitting crystals have an increased area S of more than 1 mm2 (instead of 0,05 mm2 in standard LEDs with a diameter of 5 mm), an increase in the crystal area is aimed at increasing the operating current, i.e., increasing the luminous flux and reducing the thermal resistance of the crystal;
to increase the luminous flux in a number of designs, several crystals are used, connected both in series and in parallel-series;
powerful copper or aluminum bases (radiators) are used as a crystal holder to improve heat dissipation;
appropriate reflectors were used to collect and convert the lateral radiation of the crystals;
For efficient output of radiation and formation of a given radiation pattern, LED designs contain a polymer lens matched in size with a side radiation reflector, as well as secondary optics in some designs.

At the moment, Luxeon type LEDs from Lumileds Lighting are widely used. On fig. 4.6 shows the structure of a powerful Luxeon LED.

Principles of building high-power LEDs
Rice. 4.6. The structure of a powerful Luxeon LED

A similar design has many powerful inexpensive LEDs from Chinese manufacturers. The design of the Luxeon LED ensures efficient heat dissipation from the die. A significant amount of energy supplied to the LED is still used to heat the crystal. The luminous efficiency of a white Luxeon LED at a nominal forward current of 0,3 A is 30-40 lm / W. That is, this is more than the light output of classic and halogen incandescent lamps.

Luxeon LEDs are divided by electrical power into the following series:

Luxeon - 1 W (single-chip with a direct operating current of 350 mA);
Luxeon III - 3 W (single-chip with direct operating current 0,7-1 A);
Luxeon V - 5 W (four-chip with a direct operating current of 700 mA).

Luxeon LEDs are divided by design:

Emitter - single LED (base element);
Star - Emitter on a heat sink base.

On fig. 4.7 shows the appearance of a white LED Luxeon Star (crystal and reflector are covered with a layer of yellow phosphor). And in fig. Figure 4.8 shows Luxeon Side Emitting based on Star. Thanks to a special conical lens (reverse lens) it has a circular radiation pattern.

Star/C - Emitter on square heat sink with connector

Star/O - Emitter with integrated secondary optics

On fig. 4.9 are shown from left to right Luxeon Star/O (with integrated secondary optics), Luxeon Star and Luxeon Emitter.

Ring 6, Ring 12 - a module consisting of 6 and 12 Star / O LEDs mounted on a ring base (Fig. 4.10).

Principles of building high-power LEDs
Rice. 4.7. Appearance of white LED Luxeon Star

Principles of building high-power LEDs
Rice. 4.8. Appearance of Luxeon Side Emitting based on Star

Principles of building high-power LEDs
Rice. 4.9. Appearance of white LED Luxeon Star

Principles of building high-power LEDs
Rice. 4.10. Appearance of Ring 6, Ring 12 modules

In addition to Lumileds Lighting, high-efficiency (1W) LEDs are produced by other well-known manufacturers, for example, OSRAM Optosemiconductors produces the Golden DRAGON ™ series. In table. 4.1 are given Specifications for OSRAM, NICHIA, Edixeon 1W white light LEDs.

Table 4.1. Specifications of white light LEDs OSRAM, NICHIA, Edixeon

Principles of building high-power LEDs

The next stage in the development of Luxeon LEDs was Luxeon K2 series LEDs. Variants of their execution are shown in fig. 4.11 and fig. 4.12. The following figure (Fig. 4.13) shows the internal structure of the Luxeon K2 LED.

Principles of building high-power LEDs
Rice. 4.11. Appearance of Luxeon K2 series LED based on STAR

Principles of building high-power LEDs
Rice. 4.12. The appearance of the Luxeon K2 series LED (Emitting)

Principles of building high-power LEDs
Rice. 4.13. The internal structure of the LED Luxeon K2

The luminous flux of LEDs of the Luxeon K2 series, for example, for the LXK2-PW14-V00, is 120 lm with a direct operating current of 1 A.

Author: Koryakin-Chernyak S.L.

See other articles Section LEDs.

Read and write useful comments on this article.

<< Back

Latest news of science and technology, new electronics:

A New Way to Control and Manipulate Optical Signals 05.05.2024

The modern world of science and technology is developing rapidly, and every day new methods and technologies appear that open up new prospects for us in various fields. One such innovation is the development by German scientists of a new way to control optical signals, which could lead to significant progress in the field of photonics. Recent research has allowed German scientists to create a tunable waveplate inside a fused silica waveguide. This method, based on the use of a liquid crystal layer, allows one to effectively change the polarization of light passing through a waveguide. This technological breakthrough opens up new prospects for the development of compact and efficient photonic devices capable of processing large volumes of data. The electro-optical control of polarization provided by the new method could provide the basis for a new class of integrated photonic devices. This opens up great opportunities for ... >>

Primium Seneca keyboard 05.05.2024

Keyboards are an integral part of our daily computer work. However, one of the main problems that users face is noise, especially in the case of premium models. But with the new Seneca keyboard from Norbauer & Co, that may change. Seneca is not just a keyboard, it is the result of five years of development work to create the ideal device. Every aspect of this keyboard, from acoustic properties to mechanical characteristics, has been carefully considered and balanced. One of the key features of Seneca is its silent stabilizers, which solve the noise problem common to many keyboards. In addition, the keyboard supports various key widths, making it convenient for any user. Although Seneca is not yet available for purchase, it is scheduled for release in late summer. Norbauer & Co's Seneca represents new standards in keyboard design. Her ... >>

The world's tallest astronomical observatory opened 04.05.2024

Exploring space and its mysteries is a task that attracts the attention of astronomers from all over the world. In the fresh air of the high mountains, far from city light pollution, the stars and planets reveal their secrets with greater clarity. A new page is opening in the history of astronomy with the opening of the world's highest astronomical observatory - the Atacama Observatory of the University of Tokyo. The Atacama Observatory, located at an altitude of 5640 meters above sea level, opens up new opportunities for astronomers in the study of space. This site has become the highest location for a ground-based telescope, providing researchers with a unique tool for studying infrared waves in the Universe. Although the high altitude location provides clearer skies and less interference from the atmosphere, building an observatory on a high mountain poses enormous difficulties and challenges. However, despite the difficulties, the new observatory opens up broad research prospects for astronomers. ... >>

Random news from the Archive

Ancient penguin feathers 02.08.2011

In Peru, paleontologists have unearthed an almost complete skeleton of an ancient bird, the distant ancestor of the emperor penguin.

The height of the penguin, who lived near the equator more than 36 million years ago, was one and a half meters. Even the feathers have survived. The color of the plumage was reddish-gray, in contrast to modern penguins, whose coloring is dominated by black and white.

Other interesting news:

▪ The danger of space debris

▪ Electric submarine for tourists

▪ The benefits of education for memory retention

▪ Smart alarm clock EzLarm

▪ Algae fuel

News feed of science and technology, new electronics

Interesting materials of the Free Technical Library:

▪ site section Power regulators, thermometers, heat stabilizers. Article selection

▪ article Revolutionaries in a dressing gown and shoes. Popular expression

▪ article In which country is the official Twitter account maintained by ordinary citizens, replacing each other? Detailed answer

▪ article Operator at the checkpoint. Standard instruction on labor protection

▪ article Alto sound simulator. Encyclopedia of radio electronics and electrical engineering

▪ article Power regulator on a triac. Encyclopedia of radio electronics and electrical engineering

Leave your comment on this article:

All languages of this page

Home page | Library | Articles | Website map | Site Reviews