Holographic optical element converting the Gaussian laser beam into a more uniform one

A surface relief holographic grating is designed for the transformation of a Gaussian laser beam into a beam with a flattened plateau in its central part. The depth of grating grooves varies over the surface in order to achieve a distribution of diffraction efficiency complementary to the intensity profile of the laser beam to be transformed. The appropriate efficiency distribution over the grating can be obtained by a technological process during the exposure and development. Experiments have proved that produced grating samples can sufficiently flatten the Gaussian beam, and that the degree of the beam flattening can be easily controlled.