Topological Charge Measurement of a Partially Coherent Vortex Beam Using Dual Cylindrical Lenses with an Arbitrary Angle

For a partially coherent Laguerre–Gaussian (PCLG) vortex beam, information regarding the topological charge (TC) is concealed in cross-spectral density (CSD) function phase. Herein, flexible method for simultaneous determination of sign and magnitude TC PCLG beam proposed based on measured CSD amplitude phase after propagates through dual cylindrical lens with adjustable angles. Both stripes exhibit quantitative relationships value TC, that is, N=2l+1. Meanwhile, angle adjustability lenses allows measurements, thus rendering scheme effective both high extreme coherences.