Method for reducing influence of chromatic aberration of beam splitter prism on wavefront detection precision of phase difference method

Abstract

The invention discloses a method for reducing influence of chromatic aberration of a beam splitter prism on wavefront detection precision of a phase difference method, and belongs to the field of optical detection. The method comprises the steps of determining the aberration type influenced by chromatic aberration of the beam splitter prism; correcting an imaging model between a PSF image which has a specific spectral bandwidth and is influenced by the chromatic aberration of the beam splitter prism and the aberration coefficient under the central wavelength; according to the size and material of the beam splitter prism, the spectral bandwidth and the central wavelength, determining a specific quantization function relationship between the aberration coefficient variation caused by the chromatic aberration of the beam splitter prism and the wavelength, and obtaining an imaging model between the PSF image and the aberration coefficient under the central wavelength; collecting two PSF image pairs at different focal plane positions; establishing a nonlinear equation set by using the imaging model after color difference correction and the PSF image pairs; and establishing an objective function, and solving a nonlinear equation set by using a numerical optimization algorithm. According to the invention, the wavefront detection precision of the wavefront detection method based on the phase difference principle when the beam splitter prism is applied and non-monochromatic light imaging is carried out is improved.

Description

technical field [0001] The invention belongs to the technical field of optical detection, and in particular relates to a method for reducing the influence of the chromatic aberration of a dichroic prism on the wavefront detection accuracy of a phase difference method. Background technique [0002] Large-aperture astronomical telescopes have important strategic significance for my country's scientific and technological progress and social development. It is not only a key device for studying a series of major frontier scientific issues such as the evolution of the universe, the origin of life, the nature of dark matter and dark energy, but also can provide an important driving force for original innovation in the field of optoelectronics, leading to the rapid development of several cutting-edge technologies and their industries. [0003] The increase of the mirror aperture of a large-aperture astronomical telescope poses a severe challenge to the maintenance of the imaging qu...

AI Technical Summary

Problems solved by technology

The beamsplitter prism is a transmission optical device. The refractive index of light of different wavelengths is different, and the wave aberration introduced is different (that is, there is chromatic aberration), which causes the collected point spread function (PSF) image to become blurred and reduces the accuracy of wavefront detection.

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