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[Solving resolution of diffraction gratings using coefficients of Zernike polynomials]
Hai-li Yu1, Xiang-dong Qi, Bayanheshig
1Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China. yuhailitc@163.com
Guang Pu Xue Yu Guang Pu Fen Xi = Guang Pu
|April 14, 2012
Summary
Directly testing grating resolution is difficult. This study proposes an indirect method using Zernike polynomials and wavefront aberration, reducing testing errors and complexity.
Area of Science:
- Optics and Photonics
- Diffraction Grating Metrology
Context:
- Direct resolution testing of diffraction gratings requires extensive equipment.
- Existing methods are costly and impractical due to long focal lengths.
Purpose:
- To establish a normalization model for indirectly determining grating resolution.
- To propose a novel method for resolution testing using Zernike polynomial coefficients.
Summary:
- A model based on Fourier optics and spectral imaging relates grating resolution to wavefront aberration.
- The study introduces an indirect resolution testing method utilizing Zernike polynomial fitting coefficients.
- This method employs ZYGO interferometry for wavefront aberration measurement.
Impact:
- The indirect method shows less than 4.22% error compared to direct testing.
- This approach offers a practical and less costly alternative for resolution testing.
- Enables efficient resolution measurement using standard interferometry equipment.
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