Doming (television)

As a temporary doming deformation of the hole or slot mask a picture tube is designated by the electron beam, such as high brightness or contrast, arises due to increased heating of the mask. By the deformation of the shadow mask is not correctly aligned with the light-emitting layer so that the electron beam after passing through the shadow mask not exactly match the corresponding points of the light - colored layer. This color impurities arise especially in the corners and sides of the screen, and poor brightness distribution.

In order to avoid the effect of an Invar alloy can be used for the shadow mask. Likewise stripe masks are less vulnerable because they implement only a minor portion of the energy contained in the electron beam to heat due to their smaller surface.