Improved edge detection in computational ghost imaging by introducing orbital angular momentum.

The effect of orbital angular momentum (OAM) on computational ghost imaging (CGI) with a classical or thermal source is investigated. Application of the OAM on the phase of object light is shown to enhance edge formation in the constructed image. Ghost image (GI) formation by the correlation of object and reference beams with and without OAM is studied theoretically and experimentally. In both approaches, it is confirmed that employing OAM results in higher values for visibility and contrast-to-noise ratio. Despite lowered signal-to-noise ratios in the introduced method, edge detection shows considerable enhancement over that of CGI. Additionally, compared with the previous methods for edge detection in the GI, we also show that the introduced OAM method requires lower shot numbers for image construction.