Zhanchen Zhu

Microlens arrays (MLAs) play an essential role in advanced optical systems, especially in applications such as three-dimensional imaging and augmented reality. However, the mass production of large-area MLAs on optical glass substrates remains challenging due to limitations in replication area and manufacturing efficiency inherent in conventional plate-to-plate (P2P) hot embossing. To enable the fabrication of large-area optical glass MLAs with high efficiency and consistency, this study proposes a novel roll-to-plate (R2P) hot embossing technology designed to achieve high-throughput production while addressing critical challenges in microstructure replication, including embossing-induced surface defects, unsatisfactory forming accuracy, and excessive manufacturing costs for large-area optical microstructures. A combined computational and experimental approach was employed to systematically investigate the glass filling behavior during the R2P embossing process. The parametric effects on MLA filling uniformity were quantitatively evaluated through designed factorial experiments. Optimal processing parameters were subsequently identified, enabling the successful fabrication of glass MLAs with high precision and exceptional surface consistency. This study thus demonstrates R2P hot embossing as a promising and economically attractive solution for the fabrication of advanced glass-based optical systems.

Brittle materials such as single crystals, polycrystalline ceramics, and amorphous glass are indispensable in modern industry. Driven by improvements in equipment performance, the required fabrication precision for optical elements and devices has reached nanoscale and is steadily advancing toward atomic level. Despite their outstanding physical and chemical properties, fabricating a defect-free surface with nanometer-level roughness on brittle materials is challenging due to microcracking, brittle fracture and severe tool wear. In recent years, field-assisted cutting has emerged to overcome the bottleneck in ultra-precision cutting of brittle materials. This review summarizes investigations of material removal mechanisms of brittle materials in ultra-precision cutting and surveys representative field-assisted cutting technologies—including laser, vibration, magnetic field, and ion implantation assisted cutting—highlighting how these fields broaden ductile-regime machining and suppress the machining-induced defects. This review further discusses the emerging multi-field coupling strategies and outlines future research directions in machining mechanisms to enable high-efficiency, low-damage, and high-consistency manufacturing of brittle materials.

Precision glass molding (PGM) has become an efficacious technique to fabricate high-precision optics. Chalcogenide (ChG) glass is increasingly used in thermal imaging, night vision, etc., because of its excellent infrared optical properties. Nevertheless, glass-mold interfacial adhesion has emerged as a pivotal issue within the PGM process. The interfacial adhesion during PGM has the potential to significantly undermine the performance of molded optics and reduce the longevity of molds. It is important to investigate interfacial adhesion behaviors in the PGM. In this study, the interfacial adhesion mechanism between ChG glass and the nickel-phosphorus (Ni-P) mold is analyzed using the cylindrical compression test. The effect of ChG glass internal stress on physical adhesion is investigated by finite element method (FEM) simulation. The spherical preform is proven to be capable of reducing the stress concentration and preventing physical adhesion. More importantly, a rhenium-iridium (Re-Ir) alloy coating is deposited on the Ni-P mold surface by ion sputtering to prevent atomic diffusion and resolve the problem of chemical adhesion. Finally, ChG glass microstructures with high accuracy are fabricated using the spherical ChG glass preform and the Re-Ir-coated Ni-P mold by PGM.

Precision glass molding (PGM) is an efficient process for manufacturing high precision glass optics. Chalcogenide (ChG) glass is increasingly used in thermal imaging and night vision, etc., owing to their excellent infrared optical properties. However, the glass-mold interfacial adhesion has been one of the crucial issues in the PGM production. The glass-mold adhesion in PGM could severely degrade the quality of molded optics and shorten the lifespan of the precious molds. It is important to investigate the interfacial adhesion behaviors during the molding process. In this paper, the interfacial adhesion mechanism between the ChG glass and nickel-phosphorus (Ni-P) mold is analyzed using the cylindrical compression test. The effect of ChG glass internal stress on physical adhesion is investigated by finite element method (FEM) simulation. Spherical preform is proven to be capable of reducing the stress concentration and preventing physical adhesion. More importantly, a rhenium-iridium (Re-Ir) alloy coating is deposited on the surface of Ni-P mold by ion sputtering to prevent the atomic diffusion and solve the problem of chemical adhesion. Finally, the ChG glass microstructures with high accuracy are fabricated using the spherical ChG glass preform and Re-Ir coated Ni-P mold by PGM.

Micro/nanostructured components play an important role in micro-optics and optical engineering, tribology and surface engineering, and biological and biomedical engineering, among other fields. Precision glass molding technology is the most efficient method of manufacturing micro/nanostructured glass components, the premise of which is meld manufacturing with complementary micro/nanostructures. Numerous mold manufacturing methods have been developed to fabricate extremely small and high-quality micro/nanostructures to satisfy the demands of functional micro/nanostructured glass components for various applications. Moreover, the service performance of the mold should also be carefully considered. This paper reviews a variety of technologies for manufacturing micro/nanostructured molds. The authors begin with an introduction of the extreme requirements of mold materials. The following section provides a detailed survey of the existing micro/nanostructured mold manufacturing techniques and their corresponding mold materials, including nonmechanical and mechanical methods. This paper concludes with a detailed discussion of the authors recent research on nickel-phosphorus (Ni-P) mold manufacturing and its service performance.