Simulation study on retinal imaging display based on meta-surface micro-nano structures
Based on generalized Snell's law and geometric phase metasurface regulation principle,the focusing characteristics of metasurface micro-nano structures were investigated using the finite-difference time-domain(FDTD)method.A retinal projection imaging system based on the Maxwellian view method was designed,and the imaging simulation of the whole system was realized by simulating the thin beam with Gaussian light source.Firstly,based on the TiO2 nano-structure unit,the metalens with a radius of 4.875 μm and a numeri-cal aperture of 0.44 was realized.The error between the simulation value and the design value of the focus po-sition is only 0.4%.Then,it is proved that the same numerical aperture of the metalens has the same imaging effect,and therefore the micro-level simulation can be extended to large size.Finally,the simulation of the retinal projection imaging system shows that imaging of image sources with pattern information can be a-chieved.In addition,the image source pattern can be restored on the different imaging surfaces.It means that the focusing of the eyes does not affect the resolution of the virtual image,and the vergence-accommodation conflict(VAC)can be effectively solved.The retinal projection imaging display based on metasurface micro-nano structure provides a new choice for the development of ultra-thin,ultra-light and non-VAC near-eye dis-play devices.
metasurfacefinite difference time domain(FDTD)metalensretinal projection imaging displayvergence-accommodation conflict