Semi-tempered glass is annealed glass through high temperature and quenching. The surface layer forms a compressive stress of less than 69 MPa, which increases the mechanical strength of the glass several times. After it is broken, it has the same thermal shock resistance and will not self-explode.

Tempered glass is annealed glass through high temperature and quenching, forming a strong compressive stress on the surface, which increases the mechanical strength of the glass several times. The surface stress of tempered glass is 69～168 Mpa. As a safety glass, it will be broken into small obtuse-angled particles, which will not cause major harm to the human body. Its impact resistance and bending strength are 4 times or more that of ordinary glass, and it has good thermal stability.