FLAT BED TYPE READING DEVICE

PURPOSE:To correct a white level and to improve picture quality according to a condition and kinds of an original by installing a light quantity reference plate to adjust illumination light quantity, adjust a gain of a video amplifier and adjust a reading start position. CONSTITUTION:A white light quantity position reference plate 8 having a black position reference line with prescribed length and width is installed between a case 1 and a glass plate 2 of a reading device. The light quantity position reference plate 8 is used in which printing paper of a photo is developed and fixed (white), and the above-mentioned black position reference line is added to the plate. A scanning part 3 is placed to a position of the reference plate 8 before a reading of an original 7 is started and here, after light quantity of a fluorescent lamp, a gain of a video amplifier and a standard position of read and start are adjusted beforehand, a reading of the original is scanned. In this case, a color tone difference between the original and the reference plate 8 is executed by a white level correcting circuit (not shown in figure).