The beam distance is measured in meters or feet. This measures how far the light reaches before it diminishes. Simply speaking, it measures how far ahead you’ll be able to see using your flashlight. In terms of beam distance, there are two types of light dispersals, one that sheds light in terms of length and one that sheds light widely. This mainly depends on the type of reflector or lens your flashlight has.

The beam distance is not actually measured. Instead the value is calculated by taking the peak beam intensity measured above, dividing by 0.25 lux, and taking the square root of the result. For example, if a flashlight has a peak beam intensity of 1,622 cd. Divide this by 0.25 to get 6,488. Now take the square root to get 80.55. Therefore, the beam distance of this flashlight is 81 meters.

In general, flashlights that ‘flood’ a wide area with light tend to have a shorter beam distance, but spread the total lumens to a larger space. Hence, people prefer using this for activities that are close-up. Generally, people who use flashlights for the sole purpose of close up tasks when camping, working on a car, or DIY projects stick to a flood beam.

However, if you need your light to travel a long distance, you will need to choose one that “throws” light (longer range) instead of “flooding” (wider range). People choose this type of flashlight for activities that involve long-distances, such as search and rescue, biking, night hiking, etc.
Using a tactical spotlight with a tight, long-distance beam indoors or in close up situations may actually be harder on your eyes.  At close range, the “hot spot” of the light is a very small diameter and extremely bright.  The reflection of the light alone could hurt your eyes and make whatever your task difficult.

Post time: Apr-07-2022