Patent ID: 11893719
Assignee: NANJING UNIVERSITY OF SCIENCE AND TECHNOLOGY
Field: Computer technology (Electrical engineering)
Classification: CPC G | IPC G

Claim 1:
2. A single-shot differential phase contact (DPC) quantitative phase imaging (QPI) method based on color multiplexed illumination, comprising the steps of:
step 1, displaying color multiplexed illumination pattern irradiated samples by a computer-controlled high-contrast liquid crystal display TFT-LCD or high-density programmable LED array while sending illumination control to generate a synchronous trigger signal to a color camera to capture a color sample image, recorded as Ic; and
using an alternating illumination strategyto rotate the illumination pattern 90° in any direction to illuminate the sample to acquire a second color sample image, denoted as Ic,⊥;
step 2, separating and correcting the two captured color sample images Ic, Ic,⊥, respectively, to obtain two images corresponding to each of red, green and blue channels of sample intensity image Ir,corr, Ig,corr, Ib,corr, Ir,⊥,corr, Ig,⊥,corr, Ib,⊥,corr; step 3, solving the sample intensity images Ir,corr, Ig,corr, Ib,corr, Ir,⊥,corr, Ig,⊥,corr, Ib,⊥,corr of a single channel corresponding to the two acquired images for a spectrum and remvoing zero frequency of the spectrum so as to eliminate background term;
step 4, solving for phase transfer function (PTF) including PTFr(ρ,θ), PTFg(ρ,θ), PTFb(ρ,θ), PTFr,⊥(ρ,θ), PTFg,⊥(ρ,θ), PTFb,⊥(ρ,θ), corresponding to the two illumination patterns;
step 5, bringthe two illumination patterns corresponding to sample image spectrum and transfer function into a deconvolution calculation, and then the solving a quantitative phase distribution ϕ of the sample by the formula:, ϕ
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