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Phase modulation is first introduced into aperture-scanning Fourier ptychography. A series of images are acquired with an aperture scanning the Fourier plane of an optical system with a phase modulator. Then the reported algorithm synthesizes the captured images in the frequency domain to recover a high-resolution complex object wavefront. The leading results are considerably improved in robustness against the noises and shift errors, with a much faster convergence speed compared with the conventional scheme without phase modulation. [ABSTRACT FROM AUTHOR]

• High-precision but large-range automatic image stacking technique. • Minimizing the manual operation and additional optical modules in engineering applications. • The dynamic metric optimization strategy avoids falling into local extremes. • It's universal applicability regardless of the arrangements, aperture numbers, and coherence. Image stacking is the first step of alignment of the sparse aperture telescopes. We propose an all-purpose automatic image stacking technique using dynamic metric stochastic parallel gradient descent algorithm (DM-SPGD). With the image stacking modeled as an optimization problem, the dynamic metric functions consisting of a distance metric and an energy metric are defined. According to the judgment of the spot state, the two metrics, both computed from the focal spot at each step, are switched dynamically to perform SPGD optimization. By use of the dynamic metric functions, DM-SPGD can exactly and quickly correct any-amplitude tip/tilt errors, regardless of the array arrangements, aperture numbers and coherence as verified by simulation. In addition, jitter and changes in piston brought about by the environment have no effect on the image stacking. Multiple closed-loop image stacking experiments are performed, demonstrating that the offsets of randomly distributed spots can be all controlled below 0.5 pixels within 300 iterations (within 30 s). [ABSTRACT FROM AUTHOR]

Optical sparse aperture imaging technology has promising applications in the next generation of high-resolution imaging systems, but the phasing errors correction of sparse aperture is an urgent problem to be addressed. In this paper, we propose a blind structured-illumination super-resolution imaging system using a sparse aperture as the transmitter to overcome phasing errors and obtain higher resolution. In our scheme, an unknown pattern is projected onto the object by a sparse aperture system. By translating the unknown pattern, a sequence of modulated raw images is obtained. Based on these low-resolution raw images, the super-resolution object and the unknown illumination pattern are jointly estimated by the Adam algorithm. Here we show, both in the simulation and experiment, the resolution of reconstructions using sparse aperture as transmitter are similar to those using monolithic lens. Furthermore, we validate that the proposed method can protect the reconstruction effect from piston error and widen the tolerance range of tip/tilt error (peak-valley values) up to 0.5λ. At the same time, our proposed system can also alleviate to some extent the problem of mid-frequency modulation transfer function (MTF) attenuation that exists in sparse aperture imaging. Our approach not only simplifies the process of constructing synthetic aperture system, but also provides a novel application for synthetic aperture systems. • The introduction of structured illumination improves the resolution of synthetic aperture imaging. • Protect the reconstruction effect from piston error in the sparse aperture transmitter. • Widen the tolerance range for imaging system of tip/tilt error in sparse aperture transmitter. • Alleviate to some extent the problem of mid-frequency attenuation that exists in sparse aperture imaging. [ABSTRACT FROM AUTHOR]

• The system combines the advantages of multi vision and synthetic aperture imaging. • In this system, besides a high-resolution image captured by synthetic aperture system, lower-resolution images with parallax can be obtained by multi-vision system. • By fusing the high-resolution image and lower-resolution images, a high precision measurement can be achieved. A new system that combines multi-vision system and synthetic aperture system is proposed to improve the measurement of small-scale or longer-range object. In the system, the parallax information is recorded by multi-vision system, meanwhile, a higher optical resolution image is obtained by synthesizing several optical apertures of multi-vision system to increase the effective aperture. By fusing the higher resolution image into the parallax images, we can acquire higher resolution images with parallax information from which the measurement can be improved greatly. As an example, a trinocular vision system improved by synthetic aperture has been studied experimentally. Results show that the method can improve the resolution in detection about two times and perform more accurate measurement than traditional multi-vision system. [ABSTRACT FROM AUTHOR]