Instead of blinds or curtains this system uses iron particles suspended in liquid to block sunlight at different levels. It can also harvest heat energy from the Sun.

Magnetic iron nanoparticles are suspended in a liquid, which is contained inside vertical channels in the glass itself. These particles cloud up the window, blocking light to different degrees and soaking up heat as needed. When you want to make it transparent, switching the LaWin on triggers magnets to pull these particles out of the liquid.

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