Replication of a glass microlens array using a vitreous carbon mold

Area of Science:

• Materials Science
• Optical Engineering
• Manufacturing Technology

Background:

• Microlens arrays (MLAs) are crucial optical components.
• High-quality fabrication of glass MLAs can be costly and complex.
• Vitreous carbon (VC) offers potential as a mold material due to its properties.

Purpose of the Study:

• To propose and validate a low-cost fabrication method for high-surface-quality glass microlens arrays (MLAs).
• To investigate the use of vitreous carbon (VC) molds for glass molding.
• To analyze the optical performance of the fabricated glass MLAs.

Main Methods:

• Fabrication of a high-surface-quality MLA cavity in a vitreous carbon (VC) mold.
• Replication of a glass MLA using the VC mold via a glass molding technique.
• Optimization of molding conditions to achieve high replication quality.
• Analysis of surface roughness using root mean square (RMS) measurements.
• Evaluation of the focused beam spot characteristics.

Main Results:

• A glass MLA with a root mean square surface roughness of 4.59 nm was successfully replicated.
• The surface quality of the VC mold and the replicated glass MLA was maintained throughout the process.
• The glass molded MLA demonstrated diffraction-limited focusing performance.

Conclusions:

• The proposed glass molding technique using VC molds is a viable low-cost method for producing high-quality glass MLAs.
• The method ensures excellent surface fidelity and preserves optical performance.
• This technique holds promise for scalable and economical production of optical components.