Fig. 1. (a) Error between eiϕ(r) and 1+iϕ(r). (b) Intensity difference images and RMSE between DPC images using the WOA and those without it for different coherence parameters.

Fig. 2. (a1)–(a3) Intensity distribution, absolute value of the transfer function, and intensity spectrum at the focal plane under matched-illumination (S=1), respectively. (b1)–(b3) Intensity distribution, absolute value of the transfer function, and intensity spectrum at the focal plane under non-matched-illumination (S=0.65). (c1)–(c3) Intensity distribution, absolute value of the transfer function, and intensity spectrum at the defocus plane under non-matched-illumination (S=0.65).

Fig. 3. (a) Experimental setup. (b) Positional relationship between the LED array and the sample. (c) PGTF under different coherence parameters.

Fig. 4. Data processing steps of TI-DPC using oral epithelial cells as an example.

Fig. 5. (a) Ground-truth phase and input intensities. (b) Phase retrieval results, spectrum distribution, and phase error for matched-illum DPC, non-matched-illum DPC, TIE, and the proposed TI-DPC, respectively. (c) RMSE of non-matched-illum DPC, TIE, and proposed TI-DPC for different coherence parameters. (d) SSIM of non-matched-illum DPC, TIE, and proposed TI-DPC for different coherence parameters.

Fig. 6. (a) Reconstruction results of the step samples by non-matched-illum DPC (S=0.65), matched-illum DPC (S=1), TIE (S=0.65), and TI-DPC (S=0.65). (b) Phase profile at the locations of the green, red, blue, and yellow rectangular slices.

Fig. 7. (a) Reconstruction results of the USAF resolution test target by non-matched-illum DPC (S=0.65), matched-illum DPC (S=1), TIE (S=0.65), and TI-DPC (S=0.65). (b) Phase profile at the locations of the green, red, blue, and yellow solid lines.

Fig. 8. (a) Actual image of MLA and the ground-truth phase measured with a profilometer. (b) Reconstruction result using non-matched-illum DPC (S=0.7) and 3D point cloud matching results with the ground truth using the ICP algorithm. (c) Reconstruction result using matched-illum DPC (S=1) and 3D point cloud matching results with the ground truth using the ICP algorithm. (d) Reconstruction result using TIE (S=0.7) and 3D point cloud matching results with the ground truth using the ICP algorithm. (e) Reconstruction result using TI-DPC (S=0.7) and 3D point cloud matching results with the ground truth using the ICP algorithm. (f) Profile of the phase at the white dotted line in (a).

Fig. 9. (a) Comparison of results among three traditional quantitative phase imaging techniques and the proposed TI-DPC. (b1)–(b4) Magnified comparison of the recovered results from the four phase imaging techniques at ROI 1. (c) Quantitative phase of oral epithelial cells reconstructed by TI-DPC under a 40× objective. (d) Magnified phase distributions at ROI 2 reconstructed by TI-DPC and matched-illum DPC. (e) Phase profile at the white dotted line position in (d). (f1)–(f3) Magnified images of the phase recovered at ROI 4 by matched-illum DPC, TIE, and TI-DPC.