Its is mainly used in the buildings with natural lighting, transparence, elegant appearance, thus toughened glass is actually a kind of prestressing force glass. Methods of chemistry or physics are usually used to form the stress of pressing on the glass surface, so that the glass at first offsets the stress from surface layer while bearing the external force. All these thus improve weight-bearing capacity and tensile strength of the glass. There are two major advantages of the toughened glass: one is that the intensity is improved several times compared with the ordinary glass, bending strength is as much as 3-5 times of that of ordinary glass, shock resistance intensity is as much as 50 times of that of ordinary glass, and its security has also improved with its intensity. The second major advantage is that increase of bearing capacity improves fragile nature. And even toughened glass destroys and splits, the small chip are without acute angle, which reduces the injury to the human body greatly. Capacity to bear urgent coldness and urgent heat of toughened glass is as much as 2 times compared with the ordinary glass, and toughened glass can bear difference in temperature change of more than 150 centigrade, and bears obvious effect in preventing heat-explosion.