This is based on a ball lens. There are several ball lens hacks floating around the internet, like this "iPhone Microscope" research paper[0] and this DIY[1] to

This is based on a ball lens. There are several ball lens hacks floating around the internet, like this "iPhone Microscope" research paper[0] and this DIY[1] to build your own. Ball lenses are cheap and you can attach it to cellphone camera lens with a little M3 tape. The cutout paper part seems to just hold the slide, and pane it in front of the lens. [0] http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0017150 http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjourna... [1] http://www.instructables.com/id/Cheap-and-easy-iPhone-microscope/ http://www.instructables.com/id/Cheap-and-easy-iPhone-micros...