Lingering haze torture LED shortcomings and causes

LED, IT is the most popular topic. As long as the addition of LED two words, the product will be worth double. Manufacturers of publicity, the media to hype, almost reached the level of LED to reach the peak of perfection. However, no one has any doubt about the holy name of LED? We made a small interview, hoping to be helpful to everyone.

LED has a long future

In reality, how much fire LED?

Can be described as the fire of a mess.

Shanghai World Expo

2008 Beijing Olympic Games, Shanghai, World Expo, in 2010, so that people recognize the LED engineering lighting unlimited business opportunities.

2009 China Lighting sales of more than 200 billion yuan, in the face of the semiconductor market prospects and great temptation to seize the commanding heights of the emerging industries of semiconductor lighting battle quietly started in the world.

How close is LED to our relationship?

LED is all around us. In the civil field, LED is mainly used in the following aspects:

LED lattice

Application of A, display screen and traffic signal display light source. The application of LED lamp has the advantages of shock resistance, light response speed, electricity saving and long service life.

LED taillights LED decoration

Application of B in automotive industry. The dashboard, car interior sound lights, switch back light, reading lamp and external brake lights, tail lights, side lights and headlights contain lights for automobiles. The advantages of using LED long life and fast response.

C, LED backlight source with high efficiency side emitting backlight. Mainly used in LED backlight TV, LED light source projector. The advantages of using LED wide color gamut, thin, low power consumption.

D, LED lighting. Using LED light source energy saving features.

LED toys"

E, decoration, instructions. Mainly used in toys, decorative lights, clothing, etc.. The advantages of small volume, no pollution, rich color, non fragile and low pressure using LED.

LED bulb

F, home interior lighting. Use LED power saving, pollution-free, long-life advantages.

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LED whether there are shortcomings?

LED has shortcomings, simply put, is the price is too high.

LED advantage, has been the major media hype. Even the country's propaganda is, LED has advantages, no shortcomings. However, the current penetration rate of LED is still not high, the reason is the price problem.

Why LED prices will remain high?

Low brightness LED products, lower prices.

Due to the limitations of technology and production process, high brightness LED price is difficult to reduce costs.

The shortcomings of the LED can be subdivided into low luminous efficiency, high packaging cost, high performance materials, and ultimately lead to the high cost of manufacturing LED, the market price is naturally high. Not that LED energy saving? Why is LED luminous efficiency low?

Energy saving, refers to high light efficiency, low heat. However, the so-called energy-saving LED, mainly in the low brightness of LED products, high brightness LED is not energy saving. Today, the application of LED products are mainly used in multiple, dot matrix, and so on, and the application of low brightness LED products.

LED lattice

Due to the low luminous efficiency of LED itself, about 70% of the input power is converted into heat energy. This is the lW power LED light efficiency with the input current trend of the chart, we learned that with the increase of LED current, light efficiency decreased, the most obvious decline in white light. With the decrease of the luminous efficiency, a large amount of heat energy is produced.

Fig. 1 the change trend of lW power LED with input current

Said LED luminous efficiency is low, mainly refers to the high brightness LED, in reality, the high brightness of the LED, it is more valuable. For example, LED light source projector requires a single high brightness LED products. At this stage, high brightness, mature LED projector products are less, and the price is not cheap, the use of a special high-end materials, with high cost to achieve a high brightness, in the civilian market lost practical value.

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LED is not cheap?

Low end, low brightness LED is cheap, but high brightness, high light efficiency LED price is not cheap, at this stage there is almost no price. If you want to understand LED, you should start with its structure.

Semiconductor light-emitting devices, including semiconductor light-emitting diode (LED), digital tube, symbol tube, meter word tube and dot matrix display (matrix). In fact, the digital tube, the symbol tube, the meter tube and the matrix of each light-emitting unit is a light-emitting diode. LED, the English name Light Emitting Diode, light-emitting diode, is a solid-state semiconductor device, which can directly convert electricity into light. The core of LED is a semiconductor wafer, one end of the wafer is attached to a bracket, one end is a negative electrode, and the other end is connected with the positive pole of the power supply, so that the whole chip is encapsulated by epoxy resin.

A variety of LED

Our common LED, straw hat shaped, oval, flat head, SMD, etc.. The light emitting diode text symbol is "VD", the graphic symbol is in the common diode symbol next to add two outward small arrow, the triangle is the positive pole, the short bar indicates the negative pole. Light emitting diodes are also diverse:

1, from the color of red, green, yellow and other colors of visible light