Minimalist Laser Microscope

thingiverse

HOW IT WORKS Taking advantage of water's surface tension, you can achieve a projection of what's inside a water sample by shining laser light through a suspended droplet. We use a syringe for this purpose. The suspended droplet acts as a lens and amplifies the image. Instead of having a blurry shadow, which you would obtain by using just a regular light source; in this case, the projection will be relatively clear due to the nature of laser light. Here we use an easily-sourced class III laser (a cat training laser pointer will do!). Photons emitted by a laser are coherently in phase, such that refraction via this light source produces a higher-fidelity projection. This is the principle behind our laser microscope. Never look directly into the laser source! Long-term exposure can damage your eyes. Better be safe than sorry! This build will avoid part of this risk by housing the source and diffracting the light. BUILDING YOUR TOOL! These devices can be quite complex, but they don't have to be. Our design reduces their complexity to a bare minimum without impacting its functionality, using only 4 parts: • A class III green laser (https://tinyurl.com/yc6y6a3y) • A 12 mL syringe with blunt dispensing needles (https://tinyurl.com/y8zw2qd4) • The 3D-printed body, which holds the business-end of the laser and the syringe • The 3D-printed end cap Assemble everything as shown in the pictures. USING YOUR TOOL! • First find an interesting water sample (a puddle a couple of hours after it rains, a public fountain, a river or a lake, a murky swamp... anything you can think of!), then suck up a bit of that sample with your syringe. Go explore the wild! • Load the syringe into the microscope. • In a dark room, with the laser light on (you can use a binder clip to keep the button of the laser pressed), gently press down the syringe until an image comes in view. Be careful not to dispense too much or the droplet will fall. Go as slow as possible; patience is key! An upgrade for controlled incremental dosing of the water sample through the syringe will be uploaded at a later date. • Wait for the image to stabilize and enjoy your new living wallpaper! Don't forget to share it with friends and have fun with it! Thanks to Antonio Ianiero and Alessandro Ranellucci (http://www.unterwelt.it) for inspiring me to build this laser microscope. Check out their awesome makerspace and amazing work in Rome! For more educational material and build plans, visit Binomica Labs (https://binomicalabs.org).