This year, Professor Pringle’s EEB321 (Ecology: Species Interactions, Biodiversity and Society) class at Princeton University was given the opportunity to explore the image enhancing capabilities of foldscopes – printable microscopes made for only a dollar each. In class, we each built our own foldscope and were encouraged to explore with it. I focused on attempting to use my foldscope to examine leaf structures, from small pieces of green leaf found outside our class building.
At first, this process was entirely unsuccessful, and I began to doubt whether foldscopes were truly as easily usable as advertised. I tried moving the leaf around, shining light on it from different angles, and using the foldscope’s adaptable “zoom” capabilities to attempt to bring the leaf into focus, but still, this was the best I could do:
As you can see, I wasn’t seeing “leaf” so much as “greenish blob.”
But after much more adjustment, removal of slide layers, and wrestling with my phone’s camera until it stopped shaking long enough for me to take a photo, I finally found myself peering into the inner workings of a leaf.
The above photo illustrates the complexity of leaf structure. We can prominently see the light green veins branching across the image, but even more impressively, we can see the outlines of cell patterns. This pattern is most easily pointed to on the veins themselves, due to their lighter hue, but they can also be observed throughout the image. While I was unable to detect organelles in any of my foldscope explorations, I’m very impressed that such a portable, cheap contraption was able to expand nature’s visibility so far beyond what I can observe with my own naked eyes.
I am also curious about the aspects of the photo I could not identify: namely, the darker green “X” in the upper right and the thin, darker green line that curves alongside the main vein branch. Were those simply examples of leaf decay, or are they something more specific to leaf structure?
I conducted this project as part of Professor Pringle’s EEB321 class at Princeton University.