SHEET MATERIAL DISCRIMINATION DEVICE, IMAGE FORMATION APPARATUS AND DEVICE FOR DETECTING OPTICAL SIGNAL

摘要

PROBLEM TO BE SOLVED: To provide a sheet material discrimination device which can suppress the occurrence of erroneous detection of sheet material information while enhancing the workability at the time of placing a sheet material on a sheet material placement part.SOLUTION: A sheet material discrimination device comprises: a sheet material pressing part 103 which presses a sheet material P from above toward a sheet material placement part 104 when detecting information on the sheet material P; and a sheet material holding mechanism which can switch between the state where the sheet material P is held between the sheet material placement part 104 and the sheet material pressing part 103 and the state where the sheet material pressing part 103 is separated from the sheet material P on the sheet material placement part 104. An upper sensor unit 110A having light reception means such as a first light receiver 113 located on the upper side of the sheet material P is provided separately from the sheet material pressing part 103 and is supported by the sheet material placement part 104.SELECTED DRAWING: Figure 1