Patent ID: 7907790

Claim:
An image correcting apparatus used in a projection system which includes a plurality of projectors installed away from each other, each of which projectors modulates light emitted from a light source according to image information, and projects the modulated image on a projection surface to display a projection image, the respective projection images projected by the plural projectors being stacked to display a composed projection image on the projection surface, and the projectors correcting the image by operation of the image correcting apparatus, and the image correcting apparatus comprising: a reference image pickup device disposed at a chief audience position for observing the composed projection image to obtain an image of the projection surface on which the composed projection image is displayed and output a reference image; a plurality of detection image pickup devices each of which is disposed close to the corresponding one of the plural projectors to obtain an image of the projection surface in the same direction as the projection direction of the corresponding projector and output a detection image; and a correction control device which controls operations of the reference image pickup device and the plural detection image pickup devices, wherein the correction control device includes a plurality of shadow area judging units each of which is provided on the corresponding one of the plural projectors and judges a shadow area generated on a projection image projected by the projector other than the correction target projector of the plural projectors and displayed on the projection surface based on a detection image obtained by the detection image pickup device disposed close to the correction target projector as a target of image correction and a reference image obtained by the reference image pickup device, and a plurality of shadow correction parameter producing units each of which is provided on the corresponding one of the plural projectors and gives weights to the shadow area and the non-shadow area other than the shadow area to produce shadow correction parameter containing luminance correction weight information based on which the correction target projector corrects luminance of areas corresponding to the shadow area and the non-shadow area in the image according to the weights.