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One-dimensional Lambertian sources and the associated coherent-mode representation.
1University of Rochester, Department of Physics & Astronomy, Rochester, New York 14627, USA.
Applied Optics
|December 1, 1984
Summary
This study derives the cross-spectral density for a 1-D Lambertian source, developing a coherent-mode representation. Differences in mode strengths explain distinct radiation properties compared to incoherent sources.
Area of Science:
- Optics and Photonics
- Radiometry
- Wave Phenomena
Background:
- Understanding the radiation properties of light sources is crucial in optics.
- Characterizing sources based on their spatial coherence properties is essential for applications.
- Lambertian sources and spatially incoherent sources exhibit distinct radiative behaviors.
Purpose of the Study:
- To derive the cross-spectral density function for a large, homogeneous, one-dimensional (1-D) Lambertian source.
- To develop a coherent-mode representation in the space-frequency domain for this source.
- To compare the radiation properties of Lambertian sources with spatially strictly incoherent sources.
Main Methods:
- Derivation of the explicit form of the cross-spectral density function.
- Development of the coherent-mode representation in the space-frequency domain.
- Analysis of radiant intensity buildup from coherent-mode contributions, considering mode strengths.
Main Results:
- The cross-spectral density function for a 1-D Lambertian source was explicitly derived.
- A coherent-mode representation was successfully developed for the space-frequency domain.
- Comparison revealed that differences in mode strengths explain the distinct radiation properties of Lambertian versus incoherent sources.
Conclusions:
- The coherent-mode representation provides a framework for understanding the radiative behavior of Lambertian sources.
- Mode strength differences are identified as the key physical factor differentiating Lambertian and incoherent source radiation.
- This work offers a deeper physical insight into the radiative characteristics of different types of light sources.
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