We implement an SLM to generate laser beams of variable orbital angular momentum, also referred as Laguerre-
Gaussian beams. Input beam polarization takes into account a local birefringence of each pixel of the SLM. We identify
the beam polarization eigenstates allowing generate L-G beams of different order via matching variable birefringence of
every separate pixels. Zero-order beam passing through the SLM can interact with a generated OAM beam to create an
interference pattern. Experimental results demonstrate good agreement with simulations.