The led flood light can produce the beam width may be larger or smaller, depending on the optical system and the light source in the lamp position adjustment.
By convention, the floodlight’s beam range is determined by the direction of luminous intensity equal to 50% of the peak luminous intensity in the beam axis. The beam range of a circularly symmetric floodlight remains constant across all surfaces. The beam range of a rectangular floodlight is usually oval and is determined by two values corresponding to two planes of symmetry.
In some applications, the lamp light used is asymmetrical at peak light intensity. In this case, the beam range is equal to 50% of the light intensity of the two half-angles determined. Light intensity distribution curves led flood lights with the same intensity peak and the same beam range may have different light intensity distribution curves that will provide useful information when selecting the luminaire that best suits one flood lighting problem . Due to the narrow beam range of many floodlights, the plots in the polar coordinates of the above figure are usually not readable or inaccurate. In most floodlights, shifting the light source of the optical system will change the shape of the profile (beam range, intensity and symmetry).