The invention relates to a mobile microscopic imaging device comprising a sample stage for holding a sample to be imaged, at least one light source for illumination of the sample, an imaging panel capable of capturing an image of the sample upon transmission illumination of the sample by the light source, and an optical magnification unit between the sample and the imaging panel for guiding light from the illuminated sample to the imaging panel so that a magnified image of at least portion of the sample is formed at the imaging panel. According to the invention, the optical magnification unit comprises a filter integrated polymeric lens assembly in a transmitted light fluorescence configuration which allows for both miniaturization of the device to a truly mobile level and reducing manufacturing costs.