Fig. 1. Schematic of entangled two-photon correlated imaging^[6]

Fig. 2. Klyshko geometric optical path diagram^[6]

Fig. 3. Experimental results of correlated imaging. (a) Object in the signal beam; (b) counts rate as a function of the fiber tip's transverse plane coordinates^[6]

Fig. 4. Experimental setup of the violation of Bell inequality^[18]

Fig. 5. Experimental result of violation of Bell inequality (sinusoidal patterns of coincidence counts when orientations of phase filter in reference optical path are 0°, 45°, 90°, and 135°, respectively^[18])

Fig. 6. Experimental setup of imaging with less photons^[20]

Fig. 7. Reconstructed images of a wasp wing. (a) Image of wasp wing using 40419 detected photons; (b) reconstructed image corresponding to Fig. 7(a) when λ=5; (c) image of the same wasp wing using 738298 detected photons; (d) reconstructed image corresponding to Fig. 7(c) when λ=10^[20]

Fig. 8. Setup of photon-sparse microscopy experiment^[25]

Fig. 9. Result of photon-sparse microscopy experiment^[25]

Fig. 10. Experimental setup of quantum digital spiral imaging^[29]

Fig. 11. Results of quantum digital spiral imaging^[29] for different fractional topological charges. (a) M=-1/2; (b) M=-2/3; (c) M=-5/2; (d) M=-8/3

Fig. 12. HBT interferometry with vortex light. (a) Experimental setup; (b) hologram displayed on SLM; (c) pseudothermal beam^[56]

Fig. 13. Experimental results of HBT interferometry with vortex light under different coherent degrees. (a)-(d) first-order Young interference; (e)-(h) second-order HBT interference^[56]

Fig. 14. Experimental setup of 3D full-color computational correlated imaging^[66]

Fig. 15. Experimental results of 3D full-color computational correlated imaging. (a) Full-color reconstruction; (b) red reconstruction; (c) green reconstruction; (d) blue reconstruction^[66]

Fig. 16. Reflection confocal microscopy (RCM) scans for different onion-skin samples. (a) Untreated onion-skin; (b) onion-skin incubated for 48 h in solution of pegylated gold nanoparticles; (c) onion-skin incubated for 48 h in solution of solid gold nanoparticles with bovine serum albumin (BSA) attached to them^[130]

Fig. 17. Experimental setup of quantum pattern recognition^[132]

Fig. 18. Experimental results for human face recognition^[132]