What he means is that you should provide blanking - as in an amp which can turn the laser on and off (or turn up and down power if you are using advanced projection and colour blending) many thousand times per second. Without this capability you cannot really use the laser for scanner shows as all things you draw will have lines between them (for example, a picture of a smiley would have a line from the "head" to the eyes, then the mouth, but with blanking the laser would turn off when scanning from one area to another.
I think you can buy amps seperately and connect them to labbys to provide this feature but I don't recall which place was selling them..
Seb