IMAGE COMPOSITE METHOD AND IMAGE COMPOSITE DEVICE

摘要

PURPOSE: To attain composite images in which levels of the images are consecutive from a dark area till a bright area with a high dynamic range by employing an image pickup element whose charge storage time is controlled and calculating a ratio of gains for the two images or over whose charge storage time differs. CONSTITUTION: An image of an object formed on an image pickup section of an image pickup element 1, in which the image is converted into charges. The charge obtained for the charge storage time is converted into a voltage depending on the intensity of light and the voltage is outputted as an electric signal. Thus, the saturation of the signal is not caused even in the case of a high luminous intensity by selecting the charge storage time to be short, and conversely the signal with a sufficiently high voltage is obtained by selecting the charge storage time long in the case of a low luminous intensity. A signal CS 1 corresponding to a short charge storage time and a signal CL 1 corresponding to a long charge storage time are repeated in the charge storage time, the signal CS 1 among the signals read from a CCD 1 is stored in a memory 2 and read from the memory 2 in the same timing when the signal CL 1 is read from the CCD 1. A gain ratio calculation means 3 operates a ratio of the signals CS 1 and CL 1 within a prescribed range of levels.