Determining orbital angular momentum of light using simple convex lens

@article{Vaity2012DeterminingOA,
  title={Determining orbital angular momentum of light using simple convex lens},
  author={P. Vaity and A. G. A. Kumar and Salla Gangi Reddy and A. Aadhi and P. Chithrabhanu and Ravindra Pratap Singh},
  journal={2012 International Conference on Fiber Optics and Photonics (PHOTONICS)},
  year={2012},
  pages={1-3}
}
We show that determination of the orbital angular momentum (OAM) of an optical vortex can be possible using simple convex lens, an ubiquitous optical element found in any optics laboratory.