Programmable illumination smartphone microscopy (PISM): A multimodal imaging platform for biomedical applications

Abstract

Microscopes on the smartphone platform are handy for a wide range of applications. We report herein a programmable illumination smartphone microscopy (PISM) as a flexible multimodal imaging platform for contrast enhancement of various samples using different low-cost consumer optoelectronics parts. A miniature (0.96 inches), programmable organic light-emitting diode (OLED) display has been used as an optical source to develop the proposed PISM system. By displaying different color and binary patterns on the OLED display, six well-established imaging modes, namely bright-field (BF), dark-field (DF), oblique illumination (OI), Fluorescence imaging (FI), Rheinberg illumination (RI), and differential phase contrast (DPC) imaging have been demonstrated on a single optical setup. Furthermore, by incorporating additional optical components such as an optical polarizer into the setup, another imaging mode-polarized imaging has been realized with the proposed PISM system. The optical resolution of the designed platform is found to be 1.7 µm and delivers an acceptably resolvable image in all modalities. The versatility of the PISM has been demonstrated through imaging several specimens that include micro-beads, human epithelial check cells (HECC), starch, fungus specimen, nerve tissue cells, and red blood cells.