Patent ID: 8404350

Claim:
A transparent plate of lithium aluminosilicate glass ceramic with a composition, expressed in wt. %, consisting essentially of: Li 2 O 3.0-4.5 Al 2 O 3 18.0-24.0 SiO 2 55.0-70.0 TiO 2 0.01-2.3 ZrO 2 0.01-2.0 Σ TiO 2 + ZrO 2 0.5-4.3 SnO 2 0-0.2 MgO 0-0.8 BaO 0-3 Na 2 O 0-1.5 ZnO 0-2.5 Fe 2 O 3 40-200 ppm As 2 O 3 0.3-0.9; and having a thermal expansion coefficient (CTE) from −0.15×10 −6 /K to +0.15×10 −6 /K at 30 to 700° C.