Prior-free position detection for large field-of-view scattering imaging

Prior-free imaging beyond the memory effect (ME) is critical to seeing through the scattering media. However, methods proposed to exceed the ME range have suffered from the availability of prior information of imaging targets. Here, we propose a blind target position detection for large field-of-view scattering imaging. Only exploiting two captured multi-target near-field speckles at different imaging distances, the unknown number and locations of the isolated imaging targets are blindly reconstructed via the proposed scaling-vector-based detection. Autocorrelations can be calculated for the speckle regions centered by the derived positions via low-cross-talk region allocation strategy. Working with the modified phase retrieval algorithm, the complete scene of the multiple targets exceeding the ME range can be reconstructed without any prior information. The effectiveness of the proposed algorithm is verified by testing on a real scattering imaging system.