Apparatus for producing a printing image by means of a laser

An apparatus useful for producing a printing image on a printing medium held by a cylinder by a laser, the cylinder having an axis, the apparatus comprising:

• a crossmember;
• a laser writing head positioned on the crossmember so as to be displaceable parallel to the axis of the cylinder;
• a first protective switch configured and arranged to detect the presence of a cylinder, the first protective switch being fixedly positioned on the crossmember;
• two switching strips on the crossmember which strips expose a laser writing head displacement region therebetween having a width of the printing image;
• and
• a second protective switch attached to the laser writing head configured and arranged to switch off the laser when the laser is situated outside the laser writing head displacement region;
• wherein the two switching strips and the second protective switch are mutually configured and arranged so that the second protective switch interacts with the two switching strips.