Mask-Moving-Lithography-Based High-Precision Surface Fabrication Method for Microlens Arrays

Area of Science:

• Optics and Photonics
• Materials Science
• Microfabrication Technologies

Background:

• Microlens arrays are crucial micro-optical elements for enhancing optical system integration and performance.
• Surface shape errors and roughness are key determinants of microlens array optical characteristics and overall performance.

Purpose of the Study:

• To propose and validate a high-precision surface fabrication method for microlens arrays.
• To reduce surface shape errors and surface roughness in microlens arrays.
• To improve the fabrication precision of microlens arrays for advanced optical applications.

Main Methods:

• Utilized mask-moving-projection-lithography for precise surface fabrication.
• Employed pre-exposure technology to lower photoresist development threshold, mitigating exposure impact on surface shape.
• Applied an inverted air bath reflux method post-development to eliminate surface protrusions by achieving a molten state.

Main Results:

• Fabricated microlens arrays exhibited a root mean square error below 2.8%.
• Achieved surface roughness at the nanometer level, indicating superior surface quality.
• Demonstrated significant improvement in the fabrication precision of microlens arrays.

Conclusions:

• The proposed mask-moving-projection-lithography method effectively enhances microlens array precision.
• The combination of pre-exposure and inverted air bath reflux successfully minimizes surface defects.
• This advanced fabrication technique offers a pathway to higher-performance micro-optical systems.