PURPOSE: To reduce the trouble and the time needed for manual operations by automatically setting an image forming means at a place near a tentative focus position before the image forming position of the image forming means is manually moved.

CONSTITUTION: A RAM includes an area where the tentative focus position data on a projection lens 1018 is stored. When a manual and a displayed part of a touch panel display of an operating part 1020 are pushed, the control is started to reset the lens 1018 to a reference position. Then the lens 1018 is moved forward by an extent equal to the distance shown by the contents of a tentative focus position RAM. Then an operator releases the holding state of a stepping motor 1014 which drives the lens 1018 so that the operator can set manually the position of the lens 1018. Thus the operator moves the lens 1018 to focus it by reference to the image projected on the white paper set under a Fresnel lens 708. In such a way, the manual control operation is simplified.