@article{mercer_creath_1994, 
  title={Liquid-crystal point-diffraction interferometer}, 
  volume={19}, 
  DOI={10.1364/ol.19.000916}, 
  number={12}, 
  publisher={The Optical Society}, 
  author={Mercer and Creath}, 
  year={1994}, 
  month={Jun}
  }