Reflective metalens with enhanced off-axis focusing performance

Flat mirrors have been a consistent part of optical systems with a need to be included in devices such as microscopes and spectrometers Both the cases signify applications in which the limitations of flat mirrors are ever so important in the scope of modern optics, which has applications such as optical tweezers that require high focusing efficiency for trapping and rotation of particles Traditional invisible mirrors feature optical aberrations in off axis applications and further need multifunctional optical devices Metalenses are flat optics patterned with nanostructures, which have already given the potential for focusing and reflecting light without essential energy waste However, most conventional reflective metalenses are using a parabolic phase profile that reshapes the wavefront of the reflected beam The design based on lens models of the sphere leads to an often off the axis of propagation beam rays crossing the metalens nanoparticles, becoming specifically deviated upon them, with a loss of focal accuracy The paper presents a dielectric metalens based on the DMR structure and utilizes a dielectric Distributed Bragg Reflector ( to incorporate high reflection Accordingly, the so developed all dielectric reflector is aimed for the focusing of the incident electromagnetic waves having a wavelength in the visible range at a number of incidence angles, which, perhaps, may reduce major optical aberrations in off axis applications