Preparation And Properties Of Composite Optical Diffusion Materials Based On Microstructure

With the advent of the intelligent era,optical lighting display devices have entered thousands of households.The demand for optical diffusion materials,which play a core role in light extraction and diffusion,is increasing.Currently,the mainstream design and preparation methods for optical diffusion materials include volume diffusion and surface microstructure.Among them,the volume diffusion material achieves the diffusion effect of light by adding scattering particles,but it has disadvantages such as insignificant performance improvement and unfriendly environmental impact.The surface microstructure material changes the light path by constructing microstructures on the transparent substrate through methods such as photolithography and imprinting.However,it has drawbacks such as expensive costs and complex processes that prevent large-scale production.To address these issues,this paper proposes a new type of composite optical diffusion material that combines optical diffusion particles with microstructures,while reducing the difficulty and cost of microstructure preparation.This material achieves excellent performance in the field of optical lighting.The research mainly includes the following two aspects:High refractive index titanium dioxide（Ti O₂）and high transparency polystyrene（PS）are selected as optical diffusion agents.The surface of Ti O₂ is modified with a hydrophobic coupling agent,and a layer of PS is wrapped around the Ti O₂ core using a dispersion polymerization method to prepare PS@Ti O₂ core-shell microspheres.The influence of dispersing stabilizer content on microspheres is explored.Three sizes of microhole silicon templates are prepared by photolithography.High transparency,inertness,and high flexibility polydimethylsiloxane（PDMS）is selected as the substrate for replication.PS@Ti O₂ core-shell microspheres are introduced during the replication process to prepare a composite optical diffusion film with a surface containing a micro-column array structure.Under the conditions of 3 wt%particle addition and 50μm micro-column size,the composite film achieves the best light diffusion performance.Polymethyl methacrylate（PMMA）is used as the film-forming substrate,chloroform as the good solvent,and spin-coating and one-step phase separation methods are used to prepare a polymer porous film with a tightly arranged structure.The factors affecting the formation of the porous film are explored by adjusting PMMA concentration,relative humidity,solvent type,and substrate material,and the one-step phase separation process is monitored and analyzed.Under the condition of 10 wt%PMMA/chloroform solution and 80%relative humidity,a uniform and tightly arranged porous film structure is achieved,which exhibits strong light diffusion performance.The porous film can be used as a template to prepare a PDMS microlens film through large-scale replication,which has excellent hydrophobic and light diffusion properties.The composite film prepared by combining PS@Ti O₂ core-shell microspheres successfully softens the glare point light source into a surface light source.Thanks to the innovation of microstructure production technology,the composite film can be widely used in the field of optical lighting.In summary,the new composite optical diffusion material proposed in this paper effectively combines the advantages of volume diffusion and surface microstructure,and greatly reduces the cost and complexity of the preparation process.It has excellent light diffusion performance and has broad application prospects in the field of optical lighting..