In-focus wavefront sensing using non-redundant mask-induced pupil diversity

Area of Science:

• Optical engineering
• Astronomy
• Image processing

Background:

• Wavefront estimation is vital for optical system performance.
• In-focus image data alone presents a sign ambiguity, leading to non-unique solutions.
• Non-redundant pupil masks (NRM) offer a way to resolve this ambiguity.

Purpose of the Study:

• To develop and demonstrate a method for unambiguous wavefront estimation.
• To leverage NRM data to overcome the sign-flipping ambiguity in phase retrieval.
• To apply the developed method to simulated aberrations on the James Webb Space Telescope (JWST) mirror.

Main Methods:

• Priming Gerchberg-Saxton phase retrieval with NRM fringe phase information.
• Utilizing both full pupil and NRM data for aberration measurement.
• Simulating aberrations on the JWST segmented mirror.

Main Results:

• Successfully demonstrated unambiguous wavefront estimation.
• Accurate determination of simulated aberrations on the JWST mirror.
• Validation of the NRM-assisted phase retrieval method.

Conclusions:

• NRM data effectively breaks the sign ambiguity in wavefront estimation.
• The proposed method is applicable to complex optical systems like JWST.
• Accurate wavefront sensing is achievable using combined full pupil and NRM data.