Although the topic of the best running headlamp is hot, the discussion on the best lumens for running headlamps has not stopped. This is because headlamps not only illuminate themselves, but the intensity of the light affects our vision. The wild environment is full of uncertainties, and the premise of enjoying life is to ensure personal safety. In addition, people often judge the best lumens of headlights based on home lighting, ignoring that there is no other source of light (street lights or car lights) in the dark outdoors, and our judgment is not comprehensive. In my opinion, specific issues need to be analyzed in detail.
As we all know, lumen is the international unit of luminous flux, which is defined in terms of candela sphere angle (cd times sr). 1 lumen is the amount of light emitted in 1 spherical angle unit, emitting the same amount of energy in all directions from the light source, and the intensity is 1cd. Secondly, the light energy emitted by the light source is radiated in all directions. For the light energy passing through a certain area in unit time, it is called the radiant energy flux passing through this area. The frequency of each color light is different, and the sensitivity of the eye to each color light is also different. Even if the radiant energy flux of each color light is equal, it cannot produce the same brightness visually.
The most commonly used LED lamps are generally 50-70 lm/W, and energy-saving lamps are 50-80 lm/W, which means that 1W LED lamps are equivalent to about 5W incandescent lamps. The actual light efficiency of the whole led lamp is about 70LM/W, and 200-1000 lumens is enough for dark lighting. This statement is because the larger the lumen, the faster the power consumption, and the appropriate lumen value can avoid frequent replacement of the 18650 lithium battery, thereby reducing additional troubles.
