The present disclosure relates to an optical sensor module, an optical sensing accessory, and an optical sensing device. An optical sensor module comprises a light source, a photodetector, an electrode and a substrate. The light source is configured to convert electric power into radiant energy and emit light to an object surface. The photodetector is configured to receive the light from an object surface and convert radiant energy into electrical current or voltage. The electrode is configured to detect an external circuit formed by the contact with an object surface. An optical sensing accessory and an optical sensing device comprise the optical sensor module and other electronic modules to have further applications.