Subaperture translation estimation accuracy in transverse translation diversity phase retrieval.

For optical metrology by transverse translation diversity phase retrieval (or ptychography), information theoretic limits on the ability to estimate subaperture translation, essential for accurate metrology, are assessed as a function of the optical aberrations of the system being measured. Special attention is given to the case that an unknown linear phase aberration, or equivalent detector or target motion, is present that varies with each point spread function in the measured data.