Enlarged range of measurement method with strong noise resistance for dual-wavelength digital holography

A concise and powerful method for dual-wavelength digital holography (DWDH) is proposed. By designing a new algorithm, this proposed method bypasses the phase synthesis process and directly obtains the thickness distribution of the object. This method can enlarge the range of measurement with strong noise resistance. For example, noise analysis results show that the proposed method reduces the reconstruction error from 101 nm to 9 nm when the signal-to-noise ratio is equal to 30. Therefore, this method would prove useful for DWDH, and its effectiveness is verified by both numerical simulations and experimental results.