Highly miniaturized endoscopic spatial confocal point distance sensor

We present a highly miniaturized endoscopic point distance sensor based on a spatial confocal measurement principle.(1) The sensor uses a new technique called spatial confocal point distance measurement. A special feature of the proposed sensor design is the high degree of miniaturization through femtosecond direct laser writing and the use of optical fiber bundles, which enable an endoscopic application. We show the complete sensor measurement principle, sensor head design, experimental setup, and experimental results. (C) 2020 Society of Photo-Optical Instrumentation Engineers (SPIE)