irradiance distribution

i have a uv a led with the following specification optical watt 0.103W beam angle 15 degrees distance from surface 2.4cm also the circle created by my calculation is 0.313 cmsq is the irradiance 0.103/0.313? i have attached spectral result test if that helps

Hi everyone, I’m stuck on the same problem from few days. So I’m asking for your help… The aim is to calculate the theorical irradiance distribution of a UV led on surface at a typical distance form this UV source. (Unfortunately UV LED are not an isotropic source) For example, let say: -...