| 摘要 |
<P>PROBLEM TO BE SOLVED: To positively utilize a diaphragm mechanism for picture composition and synchronize video images to be displayed with operation of the diaphragm mechanism as much as possible to alleviate unnatural luminance change of display video images apt to occur at turning points of the video images. <P>SOLUTION: An image projection device projects video images optically modulated by a display panel which forms images on the basis of a video signal on a screen. The image projection device comprises: a diaphragm mechanism arranged in a transmission path of projection light; signal level detection means for detecting the fact that the signal level of the video signal is not more than a prescribed value; signal delay means for delaying the video signal to be supplied to the display panel by a predetermined time; diaphragm operation signal generation means for generating a diaphragm operation signal when the signal level detection means detects the fact that the signal level of the video signal is not more than the prescribed value; and diaphragm mechanism control means for controlling the diaphragm mechanism on the basis of the diaphragm operation signal generated by the diaphragm operation signal generation means. <P>COPYRIGHT: (C)2013,JPO&INPIT |
