A nut 13 is provided on a holding board 9 of a barrel 8 housing a projection lens. At both sides of a holding base 11 are supporting plates 12 having a stepping shape for presenting a sliding gap, and the holding board 9 is inserted in the sliding gap. At an upper corner of the holding base 11 is a pivot pedestal 14, and a shift rod 15 is attached revolvable to the pivot pedestal 14, the shift rod 15 having a screw portion 16 that engage with the nut 13. The projection lens moves up and down driven via nut 13 by revolution of the shift rod 15, for the height adjustment of projection lens. <IMAGE>
