The LED light tube provides monochromatic light with a large half-width. Since the energy gap of the semiconductor decreases with the increase in temperature, the peak wavelength emitted by it increases with the increase in temperature, that is, the spectral red shift, and the temperature coefficient is +2~3A/. The LED luminous brightness L is approximately proportional to the forward current. As the current increases, the luminous brightness also increases approximately. In addition, the luminous brightness is also related to the ambient temperature. When the ambient temperature is high, the recombination efficiency decreases and the luminous intensity decreases.


　　 1. Look at the packaging and labels

　　 National mandatory product LED lighting manufacturers mark the following on the package: rated voltage range, rated power, and rated frequency. In general, the printed high-quality products are of good quality, clear handwriting, and not easy to fall off. Wipe with a soft damp cloth, the logo is clearly identifiable, the trademark of China 200W Led Flood Light Factory （https://www.xiangruilight.com/product/flood-light-mars-series/high-power-400w-outdoor-slim-led-floodlight-ip65-mars-series.html）and related certification marks.

　　2, look at the appearance of the LED tube

　　Real LED fluorescent lamp. From the perspective of the lamp, the shape and size of the lamp are better and more consistent, the product consistency is good, and the quality assurance is easier. Of course, there can be no cracks or looseness between the interfaces. The led tube must choose the kind of engineering plastic flame-retardant plastic PC shell. Ordinary plastic deformation and flammability, the aluminum tube must be bright, aviation aluminum.

　　3, working temperature

　　 When the LED fluorescent lamp is in normal operation, the temperature should be low. Otherwise, the life of the LED lamp is very short. At the same time, when the energy-saving lamp is lit, fast flashing or very harsh fluctuations indicate that the energy-saving lamp has quality problems. After a few minutes of power-on, there should be a temperature, which proves that the heat dissipation is good, and the aluminum substrate used for heat dissipation. Without temperature, it is a fiberglass board, and the heat cannot be dissipated.

　　4, look at the startup performance

　　China 400W Led Flood Light Factory （https://www.xiangruilight.com/product/flood-light-mars-series/high-power-200w-outdoor-slim-led-floodlight-ip65-mars-series.html） has a characteristic when looking at the start of LED fluorescent lamp: it turns on when it is powered on, and does not flicker.

　　5. Weigh the weights, compare the weights with each other, the heavier is better than the lighter, and the heavier is better for the material.