What’s the recipe for an inexpensive, high-quality lens? Just bake it!

 

 

Ever looked at a droplet of water on a window, and thought "That looks a lot like a lens"? You're not alone. Researchers at Australian National University noticed the same thing, and they ran with it, creating a lens that's inexpensive, easy to make, and yet very high quality.

Of course, water's not the greatest material from which to make a lens -- at least, if you don't want it to evaporate away. Instead, their creation used heat-cured silicone. Simply put, a droplet of liquid silicone is applied to a curved substrate, then cured in an oven at around 158°F (70°C) for 15 minutes. After it's cured, further droplets are added and cured to adjust the curvature of the lens, and thus its focal length.

 

 

The result, says a white paper on the research, is a lens that costs as little as one cent, yet has comparable quality to a commercial microscope lens. Attached to a smartphone camera -- specifically, a Google Nexus 4 -- it's capable of clearly resolving fingerprint ridges and individual sweat pores.

The full text of the research paper can be found on the OpticsInfoBase website.

 

a) Droplet lens affixed to Google Nexus 4 smartphone; b) resolution chart comparison without (left) / and with (right) the lens affixed; c) image of finger taken without lens affixed; and d) image of fingertip with ~60x magnification from droplet lens.

(via Petapixel)