Identifying the tilt angle and correcting the orbital angular momentum spectrum dispersion of misaligned light beam.

ABSTRACT: The axis tilt of light beam in optical system would introduce the dispersion of orbital angular momentum (OAM) spectrum. To deal with it, a two-step method is proposed and demonstrated. First, the tilt angle of optical axis is identified with a deduced relation between the tilt angle and the variation of OAM topological charges with different reference axes, which is obtained with the help of a charge coupled device (CCD) camera. In our experiments, the precision of measured tilt angle is about 10^-4 rad with topological charges of -3~3. With the measured angle value, the additional phase delay due to axis tilt can be calculated so that the dispersion of OAM spectrum can be corrected with a simple formula while the optical axis is not aligned. The experimental results indicate th

SUBMITTER: Zhao P 

PROVIDER: S-EPMC5554247 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature