| 摘要 |
PURPOSE:To obtain an excessive light quantity detecting-displaying device allowing a correct MTF value to be constantly measured, by displaying whether the output signal of a self-scanning solid-state image pickup element is below or above a saturation level. CONSTITUTION:A video signal Video from an amplifier 8 is compared with a predetermined reference voltage VRef in a comparator circuit 13. When the output signal of a charge coupled device 5 is above a saturation output level due to an excessive incident light quantity, the comparator circuit 13 detects this and sets a flip-flop 14. In response to a high-level output of the flip-flop 14, a driver circuit 15 drives an excessive light quantity display 16 constituted by a display lamp such as a light-emitting diode or the like to effect display of the excessive light quantity. Thus, the operator can read only a correct MTF value from an MTF display 12 by checking for whether the MTF value is accurately measured or not through observation on the excessive light quantity display 16. |
