u2062 u2062 cos u2061 u03b8 1 2 where u03b8 is a beam angle of the led module that is the maximum distance between the two led modules can be determined according to the beam angle u03b8 of the led module as well as the distance between the led module and the target illuminated zone then the light emitting surface curvature and the installation angle of the led lamps are regulated according to the installation height of the actual led lamps and the range to be irradiated case for a high pole lamp on a high speed parking lot it was found by measurement and dialux optical simulation that the light uniformity of the target illuminated zone was only 0 29 with the light spot very obvious while after using the led lamp of this structure of this example it was found that the target illuminated zone had a very pale light spot with the light uniformity also improved significantly to reach the level of 0 43 as shown in fig9 12 the structure of this led module provided by this example is similar to that in example 1 with the main difference in the following aspects a in this example the base 1 having an external contour of a regular hexagonal prism is provided thereon with six air convection cooling holes 3 going through this base which are disposed on the six edges of the regular hexagonal prism respectively b the led circuit board is provided with six led lamp beads not shown in.