Liquid Camera Lens uses water and sound

Liquid Camera Lens uses water and sound. Researchers at Rensselaer Polytechnic Institute have designed and tested an adaptive liquid lens that captures 250 pictures per second and requires considerably less energy to operate than competing technologies. The series of time-lapse photos shows how the lens, made up of two droplets of water vibrating at a high speed, changes shape and, in turn, moves in and out of focus. The time between frames is four milliseconds.

The lens is made up of a pair of water droplets, which vibrate back and forth upon exposure to a high-frequency sound, and in turn change the focus of the lens. By using imaging software to automatically capture in-focus frames and discard any out of focus frames, the researchers can create streaming images from lightweight, low-cost, high-fidelity miniature cameras.

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