Back plate

Abstract

A back plate configured to press a mask assembly. The mask assembly includes a glass substrate and a mask that are stacked on the glass substrate. The back plate covers a surface of the glass substrate to press the glass substrate, thereby attaching the glass substrate to the mask. The back plate includes a bottom plate and multiple protrusions, the multiple protrusions include multiple bottom plate protrusions disposed on a side of the bottom plate facing the glass substrate. The multiple bottom plate protrusions are arranged in an array. Orthographic projections of the bottom plate protrusions on a plane of the mask fall within the mask. A distance between the projections of the bottom plate protrusions disposed adjacent to an edge of the mask and the edge of the mask is greater than or equal to a preset distance.

Dependencies are inferred from the claim text.