What is the principle of LED light?


LED (light emitting diode) lighting is the use of fourth-generation green light to make an LED lighting. LED is called the fourth generation light source or green light, energy saving, environmental protection, long life, small size and other characteristics, can be widely used in various directions, display, decoration, backlighting, general lighting and urban landscape and other fields.

Energy: saving energy is the environmental pollution. DC drive, ultra-low power consumption (single tube 0.03-0.06 W) electro-optical power conversion close to 100%, the same lighting effects than traditional energy sources more than 80%.

Long life: LED light source that some people call longevity, meaning light never goes out. Solid cold light source, epoxy resin, light body and no loose parts, there is no filament light easy to burn, heat deposition, the light fades and other shortcomings, the service life of up to 60,000 to 100,000 hours, 10 times longer life than conventional light sources the above.

Many changes: LED light source can use red, green, blue color theory, under the control of computer technology to make three colors with 256 gray scale, and any mix can produce 256 × 256 × 256 = 16777216 colors, to form a different light The varied color combination, to achieve a variety of dynamic effects and variety of images.

Lee Green: Environmental benefits of better, no ultraviolet and infrared spectra, neither heat nor radiation, glare is small, and recyclable waste, no pollution, no mercury elements, cold light source, safe touch, typical of the green lighting.

High-tech tip: Compared with traditional light glow monotonous, LED lighting is low voltage microelectronic products, the successful integration of computer technology, network communications technology, image processing technology, embedded control technology, so it is also digital information products which such as:led ice bucket, is semiconductor optoelectronic devices, “high point” technology, with online programming, unlimited scalability, flexible features.

Terminology: wavelength: color changes in the strength of the light, it can be described by the data, the data is called wavelength. Wavelength of light that we can see, in the range of 380 to 780nm. Unit: nanometer (nm)
Brightness: Brightness is the degree of shading of the object, defined as the luminous intensity per unit area. Unit: nits (nit)
Intensity: refers to the brightness of the light source. Also means that the visible radiation source in a certain direction and scope of the issue of physical strength.
Unit: candle (cd)
Flux: the sum of the amount of visible light emitted per second. Unit: lumens (Lm)
Light efficiency: light flux emitted divided by the power source. It is an important measure of light energy. Unit: lumens per watt (Lm / w).
Color: light on the extent of the object presented, that is, the degree of color fidelity. Commonly referred to as “CRI” units: Ra.

Color: the color of a light source for emitting light and blackbody radiation at a certain temperature while the hue, the color temperature of the blackbody temperature of the light source is called.
Unit: Kelvin (k).
Glare: within view of the very high brightness of an object or a strong brightness contrast, caused visual discomfort known as glare, glare is an important factor affecting the quality of lighting.
Synchronization: two or more LED lamps in normal operation is not predetermined manner according to the procedure set time, generally refers to the internal control mode LED lights, LED lamp to achieve synchronization is coordinated changes in the basic requirements.

Protection class: IP protection class is lighting according to their dust, anti-moisture characteristics to grade, consisting of two figures, the first number represents the light dust, to prevent invasion of foreign objects grade (grade 0-6 points ), and the second number represents the lamp against moisture, water intrusion sealing degree (grade 0-8 points), the larger the number, the higher its protection.
Design Theory
The emergence of LED design methods and ideas to break the traditional light sources, there are two new design concepts.
1. Scenario Lighting: is the demand environment to design lamps. Mood lighting in place as a starting point, aims to create a beautiful, brilliant light environment, to heighten the effect of the scene, people feel there is a scene atmosphere.

2. mood lighting: is the person needs to design lamps. Mood lighting is human emotion as a starting point, from a human point of view to create a mood like light conditions. Mood lighting includes four aspects: First, energy saving and environmental protection, the second is health, three are intelligent, four are humane.
“Mood lighting book” is China’s first LED lighting design trends of the leading books, breaking the design theory has long been monopolized by foreign giants situation, make it easier for LED application market needs. The latest mood lighting design contribute to share with you, I hope to take more experts, designers participate in discussions and proposed the construction of meaning
What is the principle of LED light?

Mainly by the PN junction light emitting diode chip, the electrodes and the optical system. Its luminous body – wafer area 10.12ml (1mil = 0.0254 mm2), the big chip LED current international, the chip area of ​​40mil.
Luminescence process consists of three parts: a forward bias carrier injection, recombination radiation and energy transfer. Tiny semiconductor chip is packaged in a clean epoxy material, when the electrons pass through the wafer, the negatively charged electrons move to the positively charged area of ​​the hole and with the compound, while the disappearance of electrons and holes generate photons. Energy (band gap) between the electron and hole the greater the energy produced higher photon. The energy of the photons, in turn, corresponds with the color of the light, the visible spectral range, blue light, violet light energy carried up, orange light, red light energy to carry the least. Since different materials have different band gaps, it is possible to emit different colors of light.
Mainstream LED lighting will be the high-brightness white LED. At present, the commercialization of white LED mostly two wavelengths, ie blue chip with YAG yellow phosphor mix to produce white light. The future is more promising three-wavelength white LED, that is inorganic UV chip plus red, blue and green color phosphor mix to produce white light, it will replace the fluorescent lamps, energy-saving compact fluorescent light bulbs and LED backlight and other markets.