Brightfield imaging with PDMS lens on an upright Olympus BX 51 microscope. (a) shows the image of a slice of human colon from a fixed pathology slide taken with the PDMS lens. (b) shows the image of the same sample taken with a 10 × 0.25 NA microscope objective. (c) shows image of pollen grains on a fixed slide (Carolina Biological Supply). (d) shows grating elements on a USAF 1951 target card group (6, 7) taken at different transfer position that are spaced 200 µm apart of each other. Scale Bar (a), (b), (c), (d) 50 µm. Biomedical Optics Express
High quality lenses are essential components of microscopes, but they’re also the parts that cost the most to produce. That’s because traditional lens manufacturing requires using molds and high-precision grinders, a process that costs a lot of money and takes significant amount of time. Researchers at Australian National University developed a new method that costs less than a penny and takes little time to make a lens.
They deposited droplets of polydimethylsiloxane (PDMS), a silicon-based organic polymer, onto a curved surface and let them cure in an oven upside down. By optimizing the curvature of the substrate, they were able to create lenses with a focal point of around 2 mm, allowing for imaging of objects down to 4 µm at 160x magnification. They tested the lenses on a smartphone, achieving resolutions sufficient for dermatologic microscopy and visualizing sweat pores on the surface of the skin.
Study in Biomedical Optics Express: Fabricating low cost and high performance elastomer lenses using hanging droplets…
Optical Society: Bake your own droplet lens…