Nonparaxial optical transfer function for arbitrary illumination in partially coherent imaging systems and the...

Area of Science:

• Optical microscopy
• Image processing
• Diffraction tomography

Background:

• Partially coherent imaging setups show promise for quantitative phase and refractive index microscopy.
• The phase optical transfer function (POTF) is critical for these methods, describing spatial frequency transmission.
• Existing POTF expressions are often limited to specific, axially symmetric illumination conditions.

Purpose of the Study:

• To derive a generalized one-dimensional integral representation of the POTF for arbitrary illumination in imaging systems.
• To extend the applicability of POTF calculations beyond axially symmetric setups.
• To provide a new framework for illumination design in advanced microscopy techniques.

Main Methods:

• Derivation of a general integral representation for the POTF.
• Development of an analytical solution for the POTF under oblique homogeneous disk-shaped illumination.
• Theoretical analysis of spatial frequency transmission in partially coherent imaging.

Main Results:

• A novel, general one-dimensional integral representation of the POTF has been established.
• This representation successfully generalizes existing POTF expressions.
• An analytical solution for a specific non-axially symmetric illumination case was obtained.

Conclusions:

• The generalized POTF representation offers a more versatile tool for quantitative phase and refractive index microscopy.
• This work provides a new approach for designing illumination strategies in microscopy.
• The findings can enhance the performance and applicability of partially coherent imaging techniques.