| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a projection-type video display device, in which video image for control used to focusing or trapezoidal distortion correction is properly formed on an imaging device. <P>SOLUTION: A liquid crystal panel uses an OSD circuit 28, plots and projects a stripe image, wherein a white lateral line region and a back lateral line region are formed alternately. In order to accurately perform focusing or trapezoidal distortion correction, it is desirable that the gaps between black-and-white images formed on a sensor 29 be approximately constant. The number of white images in a black-and-white image, formed on the sensor 29 in a reference zoom state, is then detected and stored in advance. Furthermore, the number of white images formed on the sensor 29 can be detected by projecting a video image for control, when actually using the projection-type video display device. A pattern (pitch) of a stripe image generated, based on the ratio of this number to the number of white images in the reference zoom state, is corrected and plotted. <P>COPYRIGHT: (C)2005,JPO&NCIPI</p> |
