A film positive or negative comprising lines of type at various sizes—some at hard-to-reproduce sizes—used to determine the exposure time for photostencils used in screen printing. By covering various portions of the step wedge and exposing portions of it for varying amounts of time, upon development, washing, and mounting the best exposure time for a particular photostencil material can be gauged. See Photostencil.
A step wedge is also an alternate term for a type of gray scale known as a step tablet. See Step Tablet and Gray Scale.