An optical device, such as a microscope, is disclosed that can be assembled from flat materials. The optical device can be assembled via a series of folds of a flat material. The optical microscope can include a stage for supporting a sample, an optic stage, and a light source. The optic stage can include one or more lenses. The optical microscope can be capable of obtaining simultaneous images from different forms of microscopy. The optical microscope may have bright field and filter field viewing capabilities wherein a user shifts from bright field to filter field by lateral movement of the stage containing a lens and a light source that cooperate to provide either the bright field or the filter field.