Spherical aberration measurement with shearing interferometer using fourier imaging and moiré method

Area of Science:

• Optical Metrology
• Lens Aberration Analysis
• Fourier Optics

Background:

• Lateral spherical aberration affects image quality in camera lenses, particularly those with low f-numbers.
• Traditional measurement methods using shearing interferometry often require complex distortion correction for fringe patterns.

Purpose of the Study:

• To develop and demonstrate an experimental method for quantitative measurement of lateral spherical aberration.
• To simplify the analysis of lateral spherical aberration by eliminating the need for fringe distortion correction.

Main Methods:

• Utilized a shearing interferometer combined with Fourier imaging and the moire method.
• Employed an optical arrangement with a plane reference wavefront.
• Measured the aberration of a camera lens with a small f/number (1.7).

Main Results:

• Successfully obtained fringe patterns directly illustrating lateral spherical aberration.
• The proposed method eliminated the necessity of fringe distortion correction.
• Quantitative measurements of lateral spherical aberration were achieved.

Conclusions:

• The developed optical arrangement offers a simplified and effective approach for measuring lateral spherical aberration.
• Using a plane reference wavefront is key to obtaining direct fringe patterns without distortion correction.
• This method enhances the efficiency of lens aberration analysis.