1. LED is a kind of semiconductor diode. Its life is very long. Its theoretical life is 100,000 hours. The life of high-pressure sodium lamp is 24,000 hours. Because unlike traditional light sources, LED needs cathode to emit electrons, so it can switch frequently without damage.

2. The efficiency of LED light source has reached 100 lm/W, and there is still much room for development. The theoretical value can reach 250 lm/W.

3. The color rendering of white LED is much better than that of high-pressure sodium lamp. The color rendering index of high-pressure sodium lamp is only 20 right and left, and white LED can reach 65-80 white LED, which is better than high-pressure sodium lamp. At the level of intermediate vision, the human eye can identify things more easily in high color temperature environment than in low color temperature environment.

4. In the optical system of lamps, the loss of light flux of LED light source is the smallest. Unlike traditional light sources, LED is a half-space light source. High-pressure sodium lamp is the light source of all-space luminescence. It is necessary to change the direction of one half space's outgoing light to the other half space by 180 degrees. When we rely on the reflector to complete, the absorption of light by the reflector and the light shielding of the light source itself are inevitable. The use of LED as a light source, there will be no loss in this respect, the utilization of light is higher than the traditional light source.

5. LED can achieve perfect dimming function. Because of the large working range of LED, its light output is proportional to the working current, so the method of reducing the current can be used to dim the light. In addition, because the frequent switch of the LED does not cause much damage to it, the dimming of the LED can also be achieved by adjusting the pulse width. By adjusting the duty cycle and working frequency of the voltage, the intensity of the LED can be effectively adjusted.

6. LED is a low voltage DC device. The voltage driving a single LED is a safe voltage, so it is a safer power supply than using a high voltage power supply, especially suitable for public places. The characteristics of DC make LED especially suitable for combining with solar energy and wind power.

7. The basic structure of LED is an electroluminescent semiconductor material, which is placed on a lead rack and sealed with epoxy resin around it to protect the inner core, so the anti-seismic performance of LED is good.

8. LED light source does not contain harmful metal mercury, unlike high-pressure sodium lamp, which does harm to the environment when it is discarded. Due to the limitation of working principle of gas discharge lamp, mercury in lamp tube inevitably becomes a major pollution source. The mercury content is about 5 mg, which is enough to cover only one ball-point pen, but it may cause 1 800 tons of water to be polluted after infiltration into the ground.  Because of the low boiling point of mercury, it can evaporate at room temperature. When the waste lamp tube is broken, the concentration of mercury in the surrounding air can instantly exceed the standard by hundreds of times.  Once Mercury enters the human body, it will destroy the central nervous system, and the human body can die by inhaling 25 grams of mercury vapor at a time.  According to the description in the pollution survey report of lighting and electrical appliances industry in China in 2011, our environment will be harmed by 70-80 tons of mercury every year.