Diffraction-limited performance and aberration tolerance of a sparse optical synthetic aperture imaging system with four sub-apertures

An investigation is made for a four-aperture, sparse optical synthetic aperture imaging system. The characteristics of both the diffraction-limited performance and the effects of aberrations on this system are obtained. According to the coverage range of optical transfer function, the space distribution's restrictive condition of sub-apertures and the diffraction-limited performance are deduced. The wavefront aberrations are classed as three types based on the relationship between the Strehl ratio and the sub-apertures' aberrations with the exponential approximation. The tolerance limits of piston error, tilt error and defocus error are calculated in terms of the Marechal criterion.