Sunday January 14 2007 00:00 IST
NEW DELHI: No more thick curtains or tinged screens to block out the sun. IIT Delhiââ¬â¢s Department of Textile Technology has now come up with a smart window that responds to outer temperatures.
While it lets in only diffused light when it is very hot, it turns clear when it gets cooler. The project was initiated at the DRDOââ¬â¢s request to build windows suitable for bunkers in the Thar Desert and other extremely hot areas.
The Defence Lab, Jodhpur, DRDO has funded the research but the IIT intends to market the windows for commercial and office use as well.
ââ¬ÅWe were asked by the DRDO to build windows for bunkers in the Thar desert or other very hot areas where the Defence forces have to operate. The windows are coated with a polymer that responds instantaneously to temperature change, that is, the windows will turn cloudy or clear at the same rate as the temperature outside is going up or down,ââ¬Â said Ashwini K Agrawal, Associate Professor, Department of Textile Technology.
ââ¬ÅThis is a sea change from the other ways that extreme heat is blocked - by coating the window with black film for instance - which actually ends up heating the glass more,ââ¬Â he adds.
The temperature range to which the window responds can be changed according to requirement. The thermo-responsive polymer, which the window is coated with, becomes solid or semi-solid when it is very hot, in effect blocking radiation but letting in diffused light. It turns liquid when it is warm, letting in the warmth of the sunlight.
Ninety percent of the radiations are dispersed by the polymer.
ââ¬ÅThis technology can be used in old age homes, for growing sensitive plants, in homes and offices. The polymer makes use of indigenous materials, so it is not very expensive,ââ¬Â says Agrawal.
http://www.newindpress.com/NewsItem...3&Title=Features+-+Health+&+Science&Topic=166
