| 摘要 |
PROBLEM TO BE SOLVED: To provide a correction means to correct the trapezoidal distortions of a projected image on a projection surface to be generated by positional relation between a projective display device and the projection surface in the projective display device, to project video on a display device on the projection surface. SOLUTION: First correction data in which a compression and extension rate of a horizontal scanning line in the horizontal scanning direction successively changes according to a line position of video data to be displayed on the display device in the vertical direction by first correction quantity according to an angle, by which a light axis of a light flux of a projector is obliquely crossed with the projection surface in the vertical direction and second correction data in which a compression and extension rate of the video data in the vertical scanning direction uniformly changes, according to the first correction quantity are created by a judging circuit 7 respectively, and the video data to serially pass a compression and extension circuit 2 in the horizontal direction to change the compression and extension rate in the horizontal direction based on the first correction data and a compression and extension circuit 3 in the vertical direction, to change the compression and extension rate in the vertical direction based on the second correction data is reflected on the display device 6. |
