二．Simulation situation
1. Simulated illuminance map:

2.Simulated light intensity curve

三．analysis:
It can be seen from the above simulation diagram that after matching the lens, the spot angle is 24 degrees (50% maximum light intensity), and the efficiency is 82%.
The maximum illuminance is 1490 lx, which fails to meet the customer's requirement of 18 degrees and the maximum illuminance is 2600 lx.

四．Suggest:
1. Replace the small light-emitting surface LED;
2. The lens height needs to be increased.