Vortex-enhanced coherent-illumination phase diversity for phase retrieval in coherent imaging systems

Area of Science:

• Optical Engineering
• Image Processing
• Metrology

Background:

• Aberrations degrade image quality in coherent imaging systems.
• Accurate aberration characterization is crucial for optical system performance.
• Existing phase-retrieval methods have limitations in accuracy and efficiency.

Purpose of the Study:

• To develop a novel phase-retrieval method for aberration characterization.
• To improve the accuracy of phase retrieval in coherent imaging.
• To validate the proposed method through simulations and experiments.

Main Methods:

• Numerical optimization of a new objective function.
• Utilizing coherent phase-diversity images as input.
• Employing a spatial light modulator to generate spiral phase masks for diversity.

Main Results:

• The proposed method demonstrates increased accuracy in retrieved phase compared to state-of-the-art techniques.
• Simulations show a consistent advantage of the new technique.
• Experimental validation successfully characterized a highly aberrated 4F optical system.

Conclusions:

• The novel phase-retrieval method offers enhanced accuracy for aberration characterization.
• Spiral phase masks provide effective diversity for improved phase retrieval.
• The technique is suitable for real-world applications, including highly aberrated systems.