This disclosure provides systems, devices, and methods for capturing and measuring surface topography. The rollers rotate by rolling along roller-engagement surfaces underlying the conveyor belt along a carryway. The brittle material can be in the form of a moving ribbon of glass sheet, where a vibrational load is applied transverse to the score line to enhance crack propagation along the score line. Therefore, the discrimination medium has unique optical characteristics such that a character, a symbol, a pattern, a figure formed by printing by a thermal printer or the like changes in color depending on the viewing angle.