LED light
One or more LED modules for generating light are usually permanently integrated in LED lights . This means that the lamp or module is no longer changed by the end user, but by the manufacturer or specialist staff. This means that the thermal path is retained even after the repair. LED retrofits in lamp form with screw or plug bases, on the other hand, are a transitional solution for conventional lights.
construction
Control gear
The operation of LED modules is decisively influenced by the current and voltage supply. Electronic control gear and converters ensure good luminous efficiency , a long service life and offer interfaces for electronic control by precisely defining the electrical parameters .
Housing with heat sink
Mechanical, optical and thermal designs of a luminaire must be coordinated with one another. Heat sinks dissipate the resulting heat loss from the semiconductor chip.
Optical system
Secondary optics ensure targeted light distribution. Optical systems, covers and lenses should let through as much light as possible. They scatter the light or direct it into focus.
LED modules
Light-emitting diodes can only be used for lighting tasks if they form a module on circuit boards . LED modules generate light via circuit boards equipped with individual LEDs. The circuit board or board is responsible for power supply, heat dissipation and control. Depending on the expansion stage, modules can already be provided with optics for directing light and a heat sink.
crisps
Chips are made of semiconductor material and are the basis of every LED solution (light sources and lights). They are available in three versions: low and mid-power LEDs, high-power LEDs and multi-chip LEDs.
Low and mid power LED
Low and mid-power LEDs consist of a plastic housing with a lead frame for power supply and heat dissipation and a chip. They are available with outputs from 0.1 to 0.5 watts . Low-power LEDs come from the early days of light-emitting diodes and are mainly used in signal lighting. Superflux models such as the Spider or Piranha are used in automotive engineering.
High power LEDs
High-performance LEDs produce an output of 1 to 5 watts and use plastic optics to achieve precise light control. They are common in street lighting .
Multi-chip LED
Here the chips are used behind a larger conversion area, for example COB LEDs ( chip on board ). Modules with these components are available in downlights, hall or table lights .
Overview of designs
- The first types were leaded LEDs (radial LEDs), usually low-power LEDs.
- COB LEDs are powerful, tightly packed LED modules. The non-encapsulated semiconductor chip is glued to the circuit board and contacted via a bonding wire as the opposite pole. The applied bubble (epoxy lens) determines the narrow or wide beam angle .
- SMD LEDs ( Surface Mounted Devices ) can be processed flexibly and are most often installed in LED lights and LED modules. There are SMD designs equipped with low-power and high-power LEDs.
Thermal management
Good heat dissipation, for example through heat sinks, is an important quality feature for LED components and modules. Because temperatures that are too high have a negative effect on service life and luminous flux . Conversely, the cooler the ambient temperature, the longer the service life and the higher the efficiency . Reputable manufacturers indicate the permissible ambient temperature on the product.
Individual evidence
- ↑ licht.wissen 17 “LED: Basics - Application - Effect”. (PDF; 5.4 MB) In: www.licht.de. licht.de - an industry initiative of the ZVEI - Zentralverband Elektrotechnik- und Elektronikindustrie e. V. , April 17, 2018, accessed on September 17, 2018 .