Fig. 1. Schematic diagram of a conventional Fourier microscope

Fig. 2. Light-path diagram of a transmission computational Fourier microscope^[27]. (a) Light wave is emitted from on-axis point; (b) light wave is emitted from off-axis point; (c) light waves are simultaneously emitted from all point sources on the LED

Fig. 3. Experimental setup diagram of transmission computational Fourier microscope ^[27]

Fig. 4. Brightfield microscopic imaging results of onion epidermal cells ^[27]. (a) Fourier spectrum image captured by the camera; (b1)--(b3) circular digital masks with different radii; (c1)--(c3) computationally detected circular Fourier spectra; (d1)--(d3) reconstructed brightfield images using computationally detected circular Fourier spectra

Fig. 5. Darkfield microscopic imaging results of onion epidermal cells ^[27]. (a) Fourier spectrum image captured by the camera; (b1)--(b4) annular digital masks with different radii; (c1)--(c4) computationally detected annular Fourier spectra; (d1)--(d4) reconstructed darkfield images using computationally detected annular Fourier spectra

Fig. 6. Semicircular DPC imaging results of onion epidermal cells from different orientations^[27]. (a) Fourier spectrum image captured by the camera; (b1)--(b8) semicircular digital masks with different orientations; (c1)--(c8) computationally detected semicircular Fourier spectra; (d1)--(d4) reconstructed DPC images using computationally detected semicircular Fourier spectra

Fig. 7. Semicircular DPC imaging results of onion epidermal cells from different radii^[27]. (a) Fourier spectrum image captured by the camera; (b1)--(b6) semicircular digital masks with different radii; (c1)--(c6) computationally detected semicircular Fourier spectra; (d1)--(d3) reconstructed DPC images using computationally detected semicircular Fourier spectra

Fig. 8. Semi-annular DPC imaging results of onion epidermal cells from different orientations ^[27]. (a) Fourier spectrum image captured by the camera; (b1)--(b8) semi-annular digital masks with different orientations; (c1)--(c8) computationally detected semi-annular Fourier spectra; (d1)--(d4) reconstructed DPC images using computationally detected semi-annular Fourier spectra

Fig. 9. Semi-annular DPC imaging results of onion epidermal cells from different radii ^[27]. (a) Fourier spectrum image captured by the camera; (b1)--(b6) semi-annular digital masks with different radii; (c1)--(c6) computationally detected semi-annular Fourier spectra; (d1)--(d3) reconstructed DPC images using computationally detected semi-annular Fourier spectra

Fig. 10. Schematic diagram of computational Fourier microscope achieving angular sampling. (a) Specimen in the focal plane of objective lens; (b)(c) specimen in the de-focal plane of objective lens

Fig. 11. Perspective images recovered from different locations of single-pixel detectors. (a1)--(a4) Rightmost, topmost, leftmost, and bottommost single-pixel detectors, respectively; (b1)--(b4) perspective images retrieved from the rightmost, topmost, leftmost, and bottommost single-pixel detectors, respectively

Fig. 12. Digitally refocused images. (a) z=-77 μm; (b) z=-10 μm; (c) z=37 μm

Fig. 13. Light-path diagram of reflection computational Fourier microscope ^[34]

Fig. 14. Perspective images recovered from different locations of single-pixel detectors^[34]. (a1)--(a4) Perspective images retrieved from bottommost, rightmost, topmost, and leftmost single-pixel detectors, respectively; (b1)--(b4) bottommost, rightmost, topmost, and leftmost single-pixel detectors, respectively

Fig. 15. Digitally refocused images of reflective specimen ^[34].(a) z=-15 μm; (b) z=10 μm; (c) z=32 μm

Fig. 16. Color image is reconstructed based on the scheme of sampling the color information of the specimen in the detection side ^[35]. (a1)--(a3) Three-channel light intensity signal separated from the image captured by the camera; (b1)--(b3) sample image corresponding to the three channels reconstructed from the three-channel light intensity signal; (c) color-perspective image synthesized by Fig. 16 (b1)--(b3)

Fig. 17. Perspective images recovered from different locations of single-pixel detectors ^[35]. (a1)--(a4) Perspective images retrieved from rightmost, topmost, leftmost, and bottommost single-pixel detectors, respectively; (b1)--(b4) rightmost, topmost, leftmost, and bottommost single-pixel detectors, respectively

Fig. 18. Digitally refocused color images^[35].(a) z=-77 μm; (b) z=-10 μm; (c) z=37 μm

Fig. 19. Principle of generating color-coded structured light patterns^[36]

Fig. 20. Color images reconstructed based on the scheme of sampling the color information of the specimen at the illumination side ^[35]. (a) 1D light intensity sequence recorded by a single-pixel detector; (b) image of specimen recovered from the 1D light intensity sequence; (c) partially enlarged view of Fig. 20(b); (d) color image recovered by demosaicing from Fig. 20 (b)

Fig. 21. Perspective images recovered from different locations of single-pixel detectors ^[35]. (a1)--(a4) Rightmost, topmost, leftmost, and bottommost single-pixel detectors, respectively; (b1)--(b4) perspective images retrieved from rightmost, topmost, leftmost, and bottommost single-pixel detectors, respectively

Fig. 22. Digitally refocused color images^[35]. (a) z=-53 μm; (b) z=22 μm; (c) z=-59 μm