High NA Microscope Objective with Depth-Dependent Spherical Aberration Correction

Overview

This project developed a high-numerical-aperture microscope objective for voxel-level reading and writing inside a 3D optical storage medium. Because the beam travels through a different thickness of material at each storage depth, the system accumulates depth-dependent spherical aberration. The design therefore had to preserve imaging performance across the storage volume, not only at a single nominal plane.

Approach

1. 01

   Translated the Project Silica-inspired storage geometry into first-order optical requirements, including numerical aperture, working distance, field, and substrate-depth conditions.

2. 02

   Designed and optimized a multi-element objective in CODE V, using a merit function that balanced aberration correction, manufacturability, and performance across representative storage depths.

3. 03

   Evaluated the objective at multiple depths and introduced a depth-dependent correction strategy so that spherical aberration could be compensated as the read-write plane moved through the medium.