Five elements that determine the direction of LED lamp technology development

As the problem of global greenhouse gas emissions is becoming more serious  approaching the critical point of self-regulation of the earth, countries have issued relevant policies. Governments around the world, including China, must implement energy conservation  emission reduction (CO2) without delay. LED lights are currently the most energy-efficient Green  environmentally friendly electric light sources have naturally become the main option for lighting energy saving  emission reduction. With the gradual reduction in the cost  price of led lamps, the speed of their popularity is also accelerating. By 2020, the market share of LED lamps will exceed 50%.

Reduce the cost of LED lights

LED chips occupy the main part of the cost of LED lamps, so the main way to reduce the cost of LEDs is to reduce the cost of LED chips. The key to the development of LED chip technology lies in the base material  epitaxial growth technology. The base material has developed  traditional sapphire materials, silicon  silicon carbide to new materials such as zinc oxide  gallium nitride. In just a few years, with the help of a series of technical improvements including chip structure, surface roughening treatment  multi-quantum well structure design, LED has achieved a huge breakthrough in light efficiency. The cost of silicon substrate is very low,  the technology is constantly improving, but the current luminous efficiency is still  satisfactory. If this development rate is maintained, once it reaches a higher level, the silicon substrate becomes the most important technical solution  becomes an inevitable choice. Enterprises will also Obtain huge economic returns.

Improve the light efficiency of LED lights

Improving light efficiency can also start with increasing the proportion of effective light. Thin film chip technology can reduce the light output loss of each side. With the reflective surface at the bottom, more than 97% of the light is output  the front, so that most of the light converted by electrical energy is effective light, which  only significantly improves the light efficiency of the LED. It also creates superior convenience for lens design. Thin film chip technology is the core technology in the production of ultra-bright LED chips.

Improve the color rendering of LED lights

In high-brightness white LEDs, a small portion of blue light has a longer wavelength after Stokes shift. This is a good thing because it allows LED lamp manufacturers to use many phosphor layers of different colors to expand the emission spectrum  effectively improve the color rendering index (CRI) of the LED. The high CRI obtained with phosphor white LEDs comes at a price, because the Stokes shift causes white LEDs to be less efficient than monochromatic LEDs. However, for most lighting applications, LED lamps with high CRI  slightly lower efficiency are preferred.

Improve the efficiency of LED lamp power supply

Regardless of whether it is a current-limiting constant current control power supply  an op amp controlled constant current power supply, the power supply problem must be solved. That is, when the switching power supply chip works, it needs a relatively stable DC voltage to power the chip,  the working current of the chip varies  one MA to several MAs. Like FSD200, NCP1012,  HV9910, this chip is high-voltage self-feeding, which is convenient to use, but high-voltage feeding causes the IC heat to rise, because the IC has to withstand about 300V DC, as long as a little current An MA also has a damage of 0.3 watts. Generally, the LED power supply is only about ten watts,  the loss of a few watts can pull down the efficiency of the power supply by a few points. Typical like QX9910. Use the resistor to pull down the electricity, so that the loss is on the resistor,  it has to be a few watts. There is also magnetic coupling, which is to use a transformer to add a winding to the main power coil, just like the auxiliary winding of the flyback power supply, so that the power of a few watts can be avoided. This is one of the reasons why transformers are used to isolate the power supply, in order to avoid the loss of a few watts of power  increase the efficiency by a few points.

Improve LED light system reliability

The overall efficiency, service life  reliability of LEDs must be improved through system optimization.

Light source: compact  efficient, choose appropriate color  output power.

Control  drive: Use electronic circuit to realize constant current drive  control of LED.

Thermal management: To achieve a longer service life, the LED node temperature must be controlled. The calculation of the heat dissipation model  the application of new materials  new processes are hot spots of LED lamp technology.

Optical components: lenses, reflectors,  light guide plate materials focus the light on the target area  disperse it around, which depends on the design requirements.

With the rapid development of LED street lamp housing technology  the gradual improvement of LED light efficiency, the application of LED lamps will become more  more extensive. Especially as the global energy shortage becomes more  more serious, LED lamps will be an inevitable choice to replace incandescent lamps, tungsten filament lamps  fluorescent lamps. In addition, in the design of indoor lamps, LEDs will tend to be intelligent, diverse  artistic.