Liquid lens-based endoscopic OCT probe with adjustable focus for 3D imaging in cross-sectionally irregular lumens.

For imaging and inspecting lumens in industrial components, endoscopic optical coherence tomography (OCT), with its high resolution and compact probe, is a promising method. The majority of OCT probes possess a fixed depth of field (DOF) and suffer from missing point clouds when measuring cross-sectionally irregular lumens, limiting their application scenarios. To address this problem, we developed an endoscopic OCT probe that incorporates dual electrically tunable liquid lenses for dynamic focal length adjustment, making the system adaptable for imaging irregularly shaped lumens.