US Patent 7322701 Projector

To provide a projector having a configuration for reflecting correction by lens shift on keystone correction and preferentially using a lens shift function. The projector includes a keystone correcting portion for applying keystone correction to an input image signal, a display device for displaying an image in accordance with an output signal of the keystone correcting portion, a projection lens for projecting the image displayed on the display device to a screen, a lens driving portion for moving the projection lens and outputting the position information on the projection lens, and a control portion for outputting parameters used for keystone correction and the position information on the lens, in which the control portion determines whether the moving distance of the lens reaches a limit value, receives a keystone adjusting signal for changing the parameters used for keystone correction and receives a keystone adjusting signal for changing parameters used for keystone correction and outputs the signal only when the moving distance reaches the limit value.