This paper first reviews the practical optical calibration constrains of the optical metrology equipment Periscope, which measures AR/VR glass’s binocular disparity by providing the numerical measurement of non-parallelism between two eyes’ optical axes. A self-adaptive calibration methodology with close loop feedback to track on the calibration tool’s accuracy is proposed to precisely calibrate the parallelism of the periscope’s two optical sensing channels and efficiently verify this parameter periodically with consistency over time or instruments. A few implementation schemes, including a passive target, an active selfreferenced target, and two different sensitivity enhanced targets are discussed in depth to compare the performance contributors: accuracy, repeatability, and system complexity, which leads to the recommendations for different application scenarios. Beyond the AR/VR disparity measurement a potential application based on the same methodology is introduced to evaluate the precision motion system’s accuracy and tolerance.
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