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Updated: Jun 16, 2026
12:14
The Generation of Higher-order Laguerre-Gauss Optical Beams for High-precision Interferometry
Published on: August 12, 2013
Parametric study of apertured focused gaussian beams
Applied Optics
|January 30, 2010
Summary
Calculations of Gaussian beams focused through annular apertures reveal asymmetric irradiance distributions near the focal plane in large focal length infrared systems. These findings challenge common assumptions about symmetry in optical system design.
Area of Science:
- Optics and Photonics
- Electromagnetism
- Infrared Systems
Background:
- Gaussian beams are fundamental in laser optics.
- Annular apertures are used to modify beam profiles.
- Near-field and focal region optics are critical for system performance.
Purpose of the Study:
- To calculate irradiance and power distributions for Gaussian beams focused through annular apertures.
- To investigate the near-field and focal vicinity.
- To analyze the impact of large focal lengths and aberrations on beam symmetry.
Main Methods:
- Utilized Fresnel diffraction integrals for calculations.
- Developed universal curves using dimensionless parameters.
- Incorporated Gaussian and sinusoidal phase aberrations.
Main Results:
- Plotted irradiance and power distributions in dimensionless parameters.
- Discovered asymmetrical irradiance distribution about the focal plane for large focal length infrared systems.
- Quantified the effects of aberrations on the beam profile.
Conclusions:
- The common assumption of focal plane symmetry is invalid for certain infrared systems.
- Asymmetry arises from large focal lengths and annular apertures.
- Aberrations further influence the beam's spatial distribution.
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