Development of micro-objective lens array for large field-of-view multi-optical probe confocal microscopy

Abstract

We describe multi-optical probe confocal microscopy using a micro-objective lens array for large areal inspection. A microlens array with 100 µm focal length, 80 µm diameter and 90 µm pitch was designed and fabricated with an array size of 10 × 10. In order to produce the high-fidelity microlens array, a UV imprinting process was employed, and a UV transparent mold for the imprinting process was manufactured by replicating a reflow lens master. A blocking filter between the microlenses was introduced to minimize crosstalk and stray light noise for high resolution and high contrast imaging. The developed system is characterized by a 1 mm × 1 mm field of view with a nano-stage with 100 µm travel length. The lateral resolution was measured to be 0.79 µm. The method can be used for various applications such as the inspection of electric devices including display panels and large-area printed circuits with a high resolution.