An ornamentaldesign for an exposure unit for lithographic plates, substantially as shown and described.
FIG. 1 is a front elevational view of an exposure unit for lithographic
plates showing my new design, the rear being a mirror image but with the
controls omitted;
FIG. 2 is a top plan view thereof;
FIG. 3 is right side elevational view thereof, the left side being a mirror
image but with the electrical cord omitted;