Four-dimensional image formation theory of optical coherence tomography

Area of Science:

• Optics and Imaging Science
• Biomedical Optics

Background:

• Optical coherence tomography/microscopy (OCT/OCM) is a powerful imaging technique.
• Existing theories often rely on approximations, limiting precision in optical resolution and imaging characteristics.

Purpose of the Study:

• To construct an accurate, non-approximated imaging theory for OCT/OCM.
• To precisely calculate optical resolution and imaging characteristics.
• To provide insights into image formation, especially with high numerical aperture (NA) systems.

Main Methods:

• Representing a broadband light source using a four-dimensional (4D) pupil function.
• Incorporating light frequency as the fourth dimension in 4D frequency space.
• Utilizing a 4D Fourier transform to connect 4D frequency space and real space.

Main Results:

• Development of an exact imaging theory for OCT/OCM.
• Precise calculation of optical resolution and imaging characteristics.
• Demonstration of the theory's utility in understanding image formation with high NA systems, handling aberrations and dispersions.

Conclusions:

• The developed theory offers an accurate, approximation-free approach to OCT/OCM imaging.
• It enhances understanding of image formation, particularly in complex optical systems.
• This provides a foundation for improved OCT/OCM system design and performance analysis.