Beam Angle
light metric
Definition of Beam Angle
Beam angle is the measurement of how wide the light spreads from a light fixture. It’s usually measured at the angle at which the light beam reaches 50% of its peak intensity.
A broad beam angle illuminates a wider area with less intense light while a narrower beam angle gives high intensity light to a smaller area.
Using this metric, light sources can be divided into:
- Narrow angle: Ranging from 5–45°, which is typical for spotlights, such as the Fully Waterproof LED Spotlight
- Wide angle: Ranging from 45–120°, typical of floodlights, for example, the Caprera 2 LED Flood Light DUAL COLOR
Beam angle is an essential metric for optimizing light coverage on your boat and ensuring your navigation lights meet nautical safety standards.
How do you choose light fixtures with the most suitable beam angle for your lighting needs?
| Beam Angle | Pro | Con | Lighting Application |
| Narrow beam angle <45° |
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| Wide beam angle >45° |
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"Floodlight would work great for a smaller boat deck light. We use it for side lighting for buoys while fishing and it lights the dock up very well when pulling into the stall." Doug D., United States
Example of Beam Angle in a Sentence
"The starboard and port sidelights of a boat should have an unbroken beam angle of 112.5°."
Synonyms: beam spread, radiation angle
Related Terms for Beam Angle