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Effects of sampling on the phase transfer function of incoherent imaging systems
Vikrant R Bhakta1, Manjunath Somayaji, Marc P Christensen
1Department of Electrical Engineering, Southern Methodist University, Dallas, Texas 75275-0338, USA. vrbhakta@ti.com
Optics Express
|November 24, 2011
Summary
Modern computational imaging requires considering the phase transfer function (PTF). This study details PTF properties in digital systems, analyzing aliasing and shifts for improved imaging performance.
Area of Science:
- Optical Imaging
- Digital Signal Processing
- Computational Photography
Background:
- Traditional optical transfer function (OTF) analysis often neglects phase information.
- Modern computational imaging systems necessitate a deeper understanding of phase effects.
Purpose of the Study:
- To investigate the properties and implications of the phase transfer function (PTF) in digital incoherent imaging systems.
- To analyze the impact of aliasing and sub-pixel shifts on the PTF.
- To explore the application of PTF analysis in diverse imaging scenarios.
Main Methods:
- Analysis of the complex frequency response of sampled digital imaging systems.
- Derivation of key PTF properties under aliased conditions.
- Examination of aliasing and sub-pixel image shift effects on phase.
Main Results:
- Demonstrated that the phase of the optical transfer function is critical in modern computational imagers.
- Quantified the effects of aliasing and sub-pixel shifts on the PTF.
- Derived specific PTF properties relevant to aliased imaging systems.
Conclusions:
- The phase transfer function plays a significant role in the performance and characterization of digital incoherent imaging systems.
- Understanding PTF behavior under aliasing and shifts is crucial for advanced imaging applications.
- PTF analysis offers valuable insights for both traditional and computational imaging.
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