Two models for partially coherent imaging

Area of Science:

• Optics and Photonics
• Image Formation Theory

Background:

• Partially coherent imaging systems are crucial in various scientific fields.
• Two distinct models, Transmission Cross Coefficient (TCC) and object spectrum shifting, are used for image formation.
• Understanding the physical underpinnings of these models is essential for accurate analysis.

Purpose of the Study:

• To elucidate the fundamental physical differences between the TCC and object spectrum shifting approaches in partially coherent imaging.
• To demonstrate that despite producing identical images, the underlying physical models are distinct.
• To highlight the limitations of the TCC approach regarding its applicability beyond image calculation.

Main Methods:

• Comparative analysis of two image formation models for partially coherent imaging.
• Utilizing eigenfunction analysis to scrutinize the physical basis of each approach.
• Examining the interchangeability of the models in specific imaging system calculations.

Main Results:

• The TCC approach employs an artificial optical model solely for image calculation.
• The object spectrum shifting approach is based on a different physical model.
• The two approaches are not interchangeable for calculations beyond direct image formation, such as entropy calculation.

Conclusions:

• The physical models underlying the TCC and object spectrum shifting methods are fundamentally different.
• The TCC approach's reliance on an artificial model restricts its application.
• Accurate physical interpretation requires distinguishing between these two image formation strategies.