Design of refractive optical elements producing required irradiance distribution in the rectangular area with big aspect ratio

Optical element design containing two groups of optical surfaces is presented. The first group produces cylindrical beam from the light source spherical beam. The second one generates required irradiance distribution from incident cylindrical beam. The method for optical elements design to generate required irradiance distribution is presented. Two optical elements producing uniform irradiance distribution in rectangular regions with sizes 17 x 4 meters and 17 x 2 meters are computed. Energy efficiency of computed optical elements exceeds 83 % and non-uniformity of generated irradiance distribution is less than 9 %.