Refractive-diffractive hybrid optics array: comparative analysis of simulation and experiments

Abstract

Hybrid optical elements, which combine refractive and diffractive optical components to enhance the optical performances by taking advantage of the optical characteristics of the individual components, have enormous potential for next-generation optical devices. However, there have not been many reports on the simulation methodology to characterize such hybrid optical systems. Here, we present a method for simulating a hybrid optical element realized by attaching an ultra-thin, flexible diffractive optics array onto a refractive optical element. The ultra-thin diffractive optical element is fabricated by direct-laser-writing technique using a femtosecond pulsed laser as the light source. A systematic investigation of the proposed simulation method, which does not require extensive hardware resources or computational time without sacrificing resolution and accuracy, is presented. The proposed scheme is validated by comparing simulation and experimental results. Simulation and experimental results on the spot size and focal length for the diffractive Fresnel zone plate (FZP) match well with typical errors of less than 6%. The aspect ratio of the focal spot sizes at the compound and FZP focal planes of the hybrid optical system from the simulation and experiment also match quite well with typical errors below 7%. This simulation scheme will expedite the designs for novel hybrid optical systems with optimal optical performances for specific applications, such as microfluidics and aberration-controlled optics.

Femtosecond Laser Fabrication of Refractive/Diffractive Micro‐Optical Components on Hard Brittle Materials

“…A systematic study of the simulated hybrid optical component approach was used to verify the optical properties and system performance. [ 168 ] The simulated and experimental results of the FZP parameters such as spot size, focal length, and aspect ratio of the spot size match very well.…”

Imaging/nonimaging microoptical elements and stereoscopic systems based on femtosecond laser direct writing

“…Owing to the instantaneous high-intensity energy of the femtosecond laser, high-precision machining of hard and brittle materials can be achieved using FLA combined with several auxiliary methods in section of "Processing principle of FLA". Graphene oxide [150][151][152] , optical glass 137,153,154 , and crystals (such as sapphire 71,155 and silicon 146,[156][157][158] ) are the most widely used laser-ablative materials. These materials have excellent physical and chemical stabilities, including high hardness, hightemperature resistance, and corrosion resistance, and are widely used in extreme fields, such as the military and aerospace industries.…”

“…Some laser-ablative materials such as glass, crystals, and graphene oxide 82,150 can also be used as laser-modified materials. Glass and crystalline materials exhibit good light transmission, and FLM can change their refractive indices, absorption coefficients, nonlinear optical sensitivities, and crystal structures 159 .…”

Parametric studies of liquid LIBS for agricultural applications

“…These factors will result in low reproducible LIBS signals, which significantly impacts the detection capability of liquid LIBS. In imaging and collection configurations, it is crucial to consider the system design [20,21]. Similarly, the design, configuration, and optimization of the sampling configurations to improve the liquid LIBS signal collection efficiency are essential for elemental identification and analysis.…”