Study Of Liquid Lens Aberration And The Aberration Correction Method

As an important device in adaptive optics,liquid lens has been widely studied and applied due to its simple structure and flexible zooming capability.However,the conventional liquid lens often introduces many aberrations due to its working principle of zooming,especially the spherical aberration portion,which has a great influence on the imaging quality of the optical system.In order to solve the problem of spherical aberration correction of liquid lenses,many scholars have invested a lot of research.However,the current problems with spherical aberration correction for liquid lenses are: the spherical aberration correction has a small focal length range,the correction capability is relatively limited,or the device structure and its control are complicated and lack stability during the dynamic correction process.Aiming at the above problems,a novel tunable liquid aspherical lens design capable of dynamically reducing spherical aberration over a wide focal length tuning range is presented in this paper.Different from conventional treatment using elastic membrane with uniform thickness,in current case,the membrane's cross-section is designed to be a plano-convex shape with aspherical contour.A design flow combining optical ray-tracing and mechanical finite element analysis is especially developed,in which through properly selecting the targeted focal length and the center thickness with respect to particular figure of merit,the membrane can be flexibly optimized to achieve dynamic spherical aberration correction capability over certain focal length range.Besides,no special refractive index matching between the filling liquid and the membrane is required,making current design more practical in real applications.In addition,this paper also proposes a combined liquid lens system design for liquid lens chromatic aberration and spherical aberration simultaneous dynamic correction.Using the chromatic aberration correction formula,the optical power of the combined system is rationally distributed.Through the combination of multiple liquid lenses and the compensating liquid,the continuously adjustable in focal length and the dynamic correction of chromatic aberration are ensured at the same time.Besides,combined with the function of the aspherical liquid lens to correct the spherical aberration,through thedesign and simulation,the combined liquid lens system with simultaneous spherical aberration and chromatic aberration is successfully realized.