IIT-Bombay Research: A smartphone microscope can identify fake notes, detect malaria

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Researchers at IIT-Bombay (IIT-B) have developed a ‘smartphone microscope’ that could identify counterfeit notes, study blood cells on slides or even check contaminants in the water. The fabricated lens can be placed over a smartphone’s camera to observe what it not visible with the naked eye.
The lens has been developed by Bhuvaneshwari Karunakaran as part of her PhD research at IIT-Bombay.

When water is filled in a glass test tube, the water surface is never flat, instead it forms a crescent shape. Similar crescents develop at the interface of two fluids, which do not mix with each other. The researchers made use of this property to make their lens. They made use of a silicone elastomer called polydimethylsiloxane (PDMS) to develop the lens and placed the PDMS on water, which does not mix with it. Instead, it forms a hemisphere at the interface of both the fluids. “Once this liquid polymer is heated, it solidifies and doesn’t deform,” said Mukherji. By applying additional pressure at one end of the fluid interface, the curvature of the lens could be altered to change the magnification. The technique used by the researchers was published in the Journal of Biomedical Optics.

“While traditional methods of fabricating lenses are expensive as they require labour and costly equipment, this is a simple, inexpensive and off-the-shelf approach to fabricate miniature lenses,” said the researchers. These microscopes can be used to see objects of about 1.5 microns in size.
Mukherji said these tiny lenses could be put to multiple use. “Right from contaminants in water to the micro-features on currency note, everything can be seen by just placing this lens over the smartphone’s camera,” he added. Karunakaran said these lenses can also be used in endoscopes and sperm counting.