Because the luminous principle of LED lamp is that the yellow light produced by the interaction of blue light and phosphor excites white light together, it is fundamentally different from that of incandescent lamp.
Because of the incandescent lamp's luminous principle, it is first heated and then luminous. So light is only a by-product of incandescent lamps, accounting for a small proportion - about 5% (halogen lamps are slightly higher, up to 8%). Of these, the remaining 73% is heat and 19% is infrared (IR).
Forty percent of the energy in the LED source is converted to light, and the remaining 60 percent is heat. Although the heat production of LED is very high, compared with incandescent lamp, its luminous efficiency has been improved a lot, and there is no generation and waste of infrared ray.
Then with the development of the times and the improvement of technology, the light efficiency of incandescent lamp is getting higher and higher, but it can reach 20 lm/w at most, which is caused by its luminous principle. It took only a few years to raise the light efficiency of white LED to 160 lm/w since it began to be used. Until recently, the light efficiency of white LED is still rising by leaps and bounds.