QUARTZ GLASS PLATE

The present invention is a quartz glass plate comprising a quartz glass plate main body, and a quartz glass member adhered via an adhesive layer to the quartz glass plate main body. In this quartz glass plate, the adhesive layer comprises silica, and the sum of the concentrations of Ca ions, which are alkaline earth metal ions, and Li, Na, and K ions, which are alkali metal ions, included in the adhesive layer, is 10 ppm by mass or lower. Provided in this manner is a quartz glass plate that allows a level difference of a uniform thickness to be formed, and that is not readily damaged by the irradiation of light comprising UV radiation. 本发明为一种石英玻璃板，其具有石英玻璃板本体与石英玻璃构件，所述石英玻璃构件隔着粘合层而与所述石英玻璃板本体粘合，所述石英玻璃板中，所述粘合层包含二氧化硅，所述粘合层所包含的作为碱金属离子的Li离子、Na离子、K离子与作为碱土类金属离子的Ca离子的浓度的合计为10质量ppm以下。由此，可提供一种石英玻璃板，其能够形成均匀厚度的段差，且不易因包含紫外线的光的照射而发生破损。