This study explores the application of precision glass molding （PGM） technology to enhance the machining accuracy and efficiency of aspherical microlens arrays （AMLA） for fiber array collimation. The research focuses on the control of mold machining accuracy and the implementation of a compensation approach to address form errors in AMLA fabrication. A localized spiral diamond milling method is introduced for machining nickel-phosphorus mold materials， tailored to the structural characteristics and stringent precision requirements of AMLA. Furthermore， a form error compensation method is developed， considering the high-temperature properties of mold and glass materials as well as process parameters affecting accuracy. By optimizing the mold profile through compensation design， the precision of PGM is significantly improved， achieving the high-accuracy fabrication of a 10×10 AMLA. The proposed process controls the form error peak-to-valley （PV） within 220-380 nm and achieves a surface roughness （R_a） of 7-10 nm， thereby enhancing optical performance. This work provides a viable and efficient technical framework for the high-precision， large-scale production of AMLA.

Ultraprecision machining;Spiral diamond milling;Aspherical microlens array;Precision glass molding;Form error