| 摘要 |
PURPOSE: An automatic iris control method for an image system is provided to vary a threshold range for input image luminance signal according to an amplified gain value range, thereby preventing excessive amplification of image noise in the dark situation for improving the image quality. CONSTITUTION: An automatic iris control method for an image system includes the steps of determining whether an input luminance signal exceeds a luminance threshold range and stopping the routine if not(S2,S13), determining whether an electronic shutter is completely opened if smaller(S3-S5), increasing a gain if completely opened for determining the increased gain is larger than a gain threshold value to control the luminance threshold range and repeating the operation of the first step(S6-S9), and reducing the gain according to a gain control mode or close the electronic shutter if larger and repeating the operation of the first step(S10-S12). |
