Design of a human eye retinal camera optical system with dual-wavelength coaxial astigmatism correction

Abstract

In order to better improve vision, an accurate measurement of the aberrations in the human eye has important experimental and clinical significance. An adaptive fundus camera that uses a double-column lens to correct human astigmatism is designed. In the illumination system, ring light generated by a pair of axicon lenses is used to illuminate the human eye, abandoning the traditional illumination method. In the target adjustment system, a simple real image is set, the plane mirror group and the double cylinder lens are adjusted, and the defocus and astigmatism of the human eye are corrected, so that the residual aberration of the human eye is controlled within the correction range of the adaptive imaging system. In the adaptive imaging system, a Shack–Hartmann wavefront sensor is used as a wavefront detector, and a liquid crystal spatial light modulator is used as a wavefront corrector to correct the high-order aberrations of the human eye. The lighting system and imaging system operate in different bands. The simulation results show that the illumination light path avoids the strongly reflected light of the cornea and can uniformly illuminate the human eye. The design of the adaptive imaging system achieves the diffraction limit, and the astigmatism is corrected by a cylindrical lens in the imaging system. Additional aberrations are generated, and the plane mirror is adjusted to adjust the optical path to accommodate human eyes with different diopters.