Method for analyzing space images of high numerical aperture imaging system

Abstract

The invention provides a method for analyzing space images of a high numerical aperture imaging system, which comprises the following steps of: initializing imaging object images into a matrix, wherein an element of the matrix is the transmissivity of an imaging object; rasterizing a partial correlated light source surface, taking each grid region as a point light source, and expressing the amplitude and the phase of the light source of the central point in the grid region by utilizing the amplitude and the phase of the light source of the central point of each region; calculating the distribution of a diffraction spectrum on an entrance pupil of an imaging system under a global coordinate system by utilizing a fourier optics theory; acquiring the imaging system; determining the distribution of the spectrum on an exit pupil of the imaging system under the global coordinate system; further determining the light intensity distribution on an image surface; and superposing the light intensity distribution on the image surface corresponding to all the point light sources, and determining the light intensity distribution on the image surface corresponding to a partial correlated light source. The method makes up the defect of analyzing view field point space images out of an axis of a high-NA (numerical aperture) imaging system by combining an imaging model of two-dimensional polarization aberration, and the method for analyzing the space images of the high numerical aperture imaging system is suitable for any high-NA imaging system.

Description

technical field [0001] The invention designs a method for analyzing the spatial image of a high numerical aperture imaging system, and belongs to the technical field of high-resolution imaging and resolution enhancement. Background technique [0002] Current high-resolution microscopes, telescopes, and lithography systems used to fabricate VLSI all use high numerical aperture (NA) imaging technology. In order to improve the resolution of the imaging system, it is necessary to use an immersion (NA>1) imaging system. Research shows that for immersion imaging systems, the scalar imaging model that ignores the vector characteristics of electromagnetic waves is no longer applicable. Only the imaging model that considers the vector characteristics of electromagnetic waves in the full optical path can accurately describe the imaging characteristics of off-axis field of view points. [0003] In an actual NA>1 polarization imaging system, polarization aberration inevitably exi...

AI Technical Summary

Problems solved by technology

However, the two-dimensional polarization aberration in the above method needs to be converted from two-dimensional to three-dimensional when combined with the imaging model, which is not accurate enough when simulating the off-axis field of view of the high-NA imaging system, and will bring a certain degree of error

Therefore, this method is not completely suitable for the imaging performance analysis of high NA imaging systems and the research on the optimization method of resolution enhancement technology for high NA imaging systems

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