MTF tests, one of the most important optical metrology tasks for AR/MR glasses, analyze the DUT’s (Device Under Test) optical resolution to provide quantitative feedback for design verification and manufacturing process control. Due to the immaturity of the whole design/fabrication technical chain, current diffractive AR glasses show strong angular resolution non-uniformity across the FOV, and the measurement’s angular accuracy and consistency significantly impact the test repeatability and reproducibility. This paper presents a novel optical calibration apparatus to enable absolute angular alignment/verification, which can be implemented with a small volume and easily fit into the metrology equipment.
|