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10:53
Simultaneous Measurement of Turbulence and Particle Kinematics Using Flow Imaging Techniques
Published on: March 12, 2019
Imaging of extended objects through a turbulent atmosphere.
Applied Optics
|February 4, 2010
Summary
This study provides an explicit formula for image illuminance, quantifying atmospheric effects on optical system resolution. It details the point spread function and modulation transfer function for atmospheric imaging.
Area of Science:
- Optics and Photonics
- Atmospheric Optics
- Image Science
Background:
- Optical imaging systems are affected by atmospheric conditions.
- Understanding image degradation is crucial for remote sensing and surveillance.
- The Huygens-Fresnel principle is a foundational concept in wave optics.
Purpose of the Study:
- To derive an explicit expression for image plane illuminance distribution for extended objects.
- To quantify the combined effects of attenuation, background luminance, and atmospheric turbulence.
- To analyze the impact of these factors on image resolution and develop a quantitative model.
Main Methods:
- Utilized the extended Huygens-Fresnel principle.
- Derived explicit expressions for image illuminance, point spread function (PSF), and modulation transfer function (MTF).
- Performed quantitative comparisons of atmospheric effects and their contribution to resolution loss.
Main Results:
- An explicit expression for image plane illuminance distribution was derived.
- Quantitative expressions for the PSF and MTF of the combined atmospheric-optical system were obtained.
- Numerical results for image plane modulation were presented for various atmospheric imaging scenarios.
Conclusions:
- The study provides a comprehensive framework for analyzing image quality degradation in atmospheric optical systems.
- The derived expressions enable quantitative assessment of resolution loss due to atmospheric turbulence and other factors.
- The findings are applicable to both upward and downward imaging through the atmosphere.
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