Near-infrared scanning holography with a Fresnel zone plate (FZP) coded aperture has potential applications in imaging through turbid media. However, the nonnegative intensity-distribution function of the FZP coded aperture introduces the background artifacts into the reconstructed images, reducing the contrast and the signal-to-noise ratio (SNR) of the images. A novel method termed as the composite hologram is proposed to reduce the artifacts. The computer simulations showed that the contrast and the SNR of the reconstructed images had improvements of at least 50.2% and 5.58-dB, respectively, compared with the conventional method. The composite hologram of a metal ring with a 6.0-mm diameter made by a wire with a 0.4-mm diameter immersing in 1% intralipid solution was recorded, and the reconstruction was performed numerically. The experimental results demonstrated that the contrast and the SNR of the reconstructed image had improvements of at least 32.3% and 2.51-dB, respectively.
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