Skip to main content
. 2017 Dec 21;7:18011. doi: 10.1038/s41598-017-18147-7

Figure 4.

Figure 4

(a) Experimental beam generated by SPP with p = 1,  = 1. Brightness and colours refer to intensity (experimental) and phase (theoretical) respectively. (b) Input image entering the optimization loop. (c) On the left: diffracted pattern window (DPW) on the object plane, including the signal window (SW) where the image is formed. At each step of the algorithm, a replacement of the output signal amplitude with the desired image amplitude within the SW is imposed, while free phase is left on the whole DPW. On the right: corresponding hologram phase pattern after 200 iterations. On the hologram plane, direct amplitude-elimination and partial phase-quantization are performed at each step. Evolution of diffraction efficiency η (d) and signal-to-noise ratio (SNR) (e) during algorithm convergence to an optimized design of the computer-generated hologram for illumination with an OAM beam with indices (p = 1,  = 1) (ac).