Nonuniform background removal in inline holography using a numerically scaled illuminating beam intensity

A unique method for removing backgrounds from inline holograms using a numerically scaled illuminating beam intensity is proposed. To eliminate differences between the intensities of the illuminating beam and recorded holograms, the scaling employs a contrast function, which is calculated in the spatial frequency domain. Since it is free from manual intensity ratio adjustment, the proposed method is applicable to Gabor's setup. The experimental results show that the proposed nonuniform background elimination method can retrieve the interference fringes better than conventional methods, improving the quality of the reconstructed images.