IMAGE INPUT DEVICE

PROBLEM TO BE SOLVED: To provide an image input device using a combination of a multi-stage diaphragm and a ND filter as a luminous energy control means, wherein chances of luminous energy control using the ND filter are decreased, so as to reduce the cost and achieve a small lens barrel and stabilized operation by reducing the size of a ND filter driving mechanism. SOLUTION: The device includes an optical means for imaging an object image, a first dimming means present on the optical axis of the optical means and controlling the luminance energy by the aperture size of a diaphragm, a second dimming means present on the optical axis of the optical means and changing a transmittance to control the luminous energy of the transmitting light, and a control means to control operations of the first and second dimming means to obtain appropriate exposure upon photographing. The control means performs appropriate exposure by giving priority to the luminous energy control by the first dimming means up to a predetermined aperture diameter of the diaphragm size and then giving priority of the luminous energy control by the second dimming means when the aperture of the diaphragm is reduced smaller than a predetermined aperture size. COPYRIGHT: (C)2007,JPO&INPIT