UROP Proceedings 2022-23

School of Engineering Department of Mechanical and Aerospace Engineering 152 Development of Low-cost Smartphone-based Microscope for Global Health Supervisor: LEE, Yi-Kuen / MAE Student: LEUNG, Chi San Ivor / PHYS Course: UROP4100, Fall We have proposed a novel way to carry out confocal microscopy, namely Tubehole Confocal Microscopy (TCM). This approach makes use of an extended infinity space (a virtual tubehole) to block the out-of-focus light according to their geometry of light rays in the infinity space. Numerical analysis is performed to decide the optimum tube length to be used. We have decided to set the tube length to be 4000 mm to test its feasibility. We also proposed another design of smartphone microscope used for water quality monitoring, using an extra infinity-corrected system to provide a larger magnification. Fig. 1. Basic principle of TCM. In both figures, yellow rays represent in-focus light, and green and red rays represent out-of-focus light. Fig. 2. Schematics of the TCM setup (A) and the widefield setup (B). Fig. 3. The TCM setup. In (B), covers are removed to show the internal structure of the microscope. The yellow rectangle indicates the objective lens and the prism, while the red rectangle indicates the tube lens and the camera sensor. The scale bar is 10 cm.