Calibration method for a multi-focus microscopic 3D imaging system

This Letter presents a novel, to the best of our knowledge, method to calibrate multi-focus microscopic structured-light three-dimensional (3D) imaging systems with an electrically adjustable camera focal length. We first leverage the con-ventional method to calibrate the system with a reference focal length f0. Then we calibrate the system with other dis-crete focal lengths fi by determining virtual features on a reconstructed white plane using f0. Finally, we fit the poly-nomial function model using the discrete calibration results for fi. Experimental results demonstrate that our proposed method can calibrate the system consistently and accurately.& COPY; 2023 Optica Publishing Group