A copy machine includes a document table on which a document is placed aligning at the left end with the left end of the document table, and a lamp, under the document table, which scans from left to right for a distance corresonding to the width of a designated copy sheet. Before the start of the copying operation, a carriage for supporting the lamp is located at a position distanced from the left end of the document table by a length corresponding to the width of the copy sheet. A display is provided on the upper surface of the carriage. Before the copying operation starts, the display emits light to indicate a copy allowable range.