Compact metrology for AR projectors and AR devices

In this work, we present a compact single-device solution for optical characterization of AR projectors and near-eye display (NED) systems. Our system combines an imaging luminance measurement device (ILMD) with Type II calibration and a liquid lens-based NED front stop lens. Type II calibration provides photometric calibration and geometric mapping between sensor pixels, viewing directions, and object distances. The liquid lens enables a short minimal focus distance to past infinity with constant image quality and no entrance pupil shift across the entire focus range. This allows us to realize a compact photometric measurement setup including a rapid alignment method. It works through focus-based distance measurements of the eyebox or exit pupil of AR devices or components. Experimental validation shows significant time savings compared to standardized eyebox scanning approaches, while maintaining similar positioning accuracy.