Fig. 1. Conventional optical imaging system. (a) Conventional optical imaging process^[2]; (b) The contradictory relationship between resolution, cost, and weight of different optical imaging systems in far-field detection^[9]

Fig. 2. (a) Michelson stellar interferometer; (b) Schematic diagram of stellar light interference; (c) Very large array (VLA) in New Mexico, USA^[12]; (d) Global very long baseline interferometry (VLBI)

Fig. 3. Imaging process of the computational optical imaging system^[2]

Fig. 4. Classification and development of synthetic aperture technique in the far-field detection

Fig. 5. Tippie's system schematic for obtaining 200-megapixel synthetic aperture digital holographic result from camera scanning and the quantitative enhancement effect of USAF resolution chart ^[21]

Fig. 6. Synthetic aperture lidar achieves azimuthal resolution enhancement by aperture synthesis with coherent illumination

Fig. 7. Fourier ptychographic microscopy imaging system and experimental results of USAF resolution chart ^[32]

Fig. 8. Schematic diagram of the camera array Fourier ptychography imaging^[37]. (a) The single aperture imaging scheme with a size of 12.5 mm; (b) The scheme to achieve 125 mm synthetic aperture imaging results using the camera array; (c) The imaging scheme in (b) using the aperture scanning to obtain effective high-resolution imaging results

Fig. 9. Synthetic apertures for long-range and subdiffraction-limited visible imaging using Fourier ptychography^[39]. (a) Imaging schematic; (b) Structural diagram of the system at 1 m imaging distance

Fig. 10. FP for improving spatial resolution in diffuse objects^[39]. (a) Resolution of a USAF target under coherent light under various imaging modalities; (b) Magnified regions of various bar groups recovered by the five techniques; (c) Contrast of the bars as a function of feature size; (d) Speckle size and resolution loss are inversely proportional to the size of the imaging aperture

Fig. 11. Schematic diagram of the positioning errors present on the LED array in the Fourier ptychographic microscopy system ^[42]. (a) Errors in the X-Y plane; (b) Pose misalignment due to the angular offset of the LED array

Fig. 12. Schematic diagram of the macroscopic Fourier ptychography imaging system based on TV regularization ^[47]

Fig. 13. Constructed vehicle dynamic pursuit imaging results^[48]. (a) Comparison of imaging results; (b, c) Comparison of magnified details; (d, e) Comparison of PSNR and SSIM as well as comparison of two car displacements

Fig. 14. 12 m far-field imaging experiments based on quasi-plane wave. (a) Experimental setup of the R-FP system; (b) The poker card scenario as the detection target; (c) Partial area enlargement of the R-FP system and low-resolution image capture; (d) Raw image of target by the sub-aperture and corresponding line profile; (e) The result of cumulative averaging method and corresponding line profile; (f) Reconstruction result of R-FP with TV regularization and corresponding line profile

Fig. 15. Typical structure of incoherent synthetic aperture

Fig. 16. Synthetic aperture of Fizeau interferometer. (a) Multi-mirror telescope (MMT); (b) Schematic diagram of the MMT^[57]; (c) James Webb space telescope (JWST); (d) Schematic diagram of the JWST^[59]

Fig. 17. Very large telescope interferometer (vlti) of the european southern observatory (ESO)^[67-68]

Fig. 18. (a) Primitive SPIDER conceptual model and decomposition diagram; (b) Schematic diagram of the internal structure of the PIC^[70]

Fig. 19. (a) Hierarchical multistage lens array with non-uniform hierarchical multistage lens array^[72-73] ; (b) Hexagonal array structure and its 3D structure model^[74]; (c) Equally spaced concentric ring arrangement of the lens array and its baseline pairing method^[75]

Fig. 20. (a) Internal structure design and experimental verification platform of the first-generation PIC ^[80-82]; (b) Three-layer structure and experimental verification platform adopted by the second-generation PIC^[83-85]

Fig. 21. (a) Schematic diagram of synthetic aperture imaging by SAFE technique; (b) Optical path of synthetic aperture imaging by OCTISAI technique^[88]

Fig. 22. (a) Schematic diagram of the principle of aperture synthesis based on autocorrelation detection; (b) Synthetic aperture imaging optical path based on autocorrelation detection; (c, d) Reconstruction results before and after aperture synthesis and detail comparison