That awakens dormant memories. In the early 1970s, I was working as a programmer for a small Cambridge UK company called Laser-Scan. Originally, it built scanners for nuclear physics research, then graphics plotters, and later it became well known in the mapping industry for the Lasertrak line-following automatic map digitiser, and for the LAMPS suite of map production software. Its descendent company is still around as 1spatial.
Anyway, we had particular expertise in computer-controlled laser deflection systems, and used to get people coming from various industries wanting us to write on something with a laser beam. One such was someone wanting to engrave live pigs with a bar-code, so that the meat could be tracked through to bacon!
Another day, there was a visit from a group of long-haired characters who wanted us to write the name of the band on the clouds above their open-air concerts. The people were Pete Townsend, Roger Daltrey, Keith Moon and John Entwistle, and the band was 'The Who'! The other programmer (Martin Fulford) and I put together a demo to use a high-powered turquise argon-ion laser to write 'The Who' and some animated figures on the oposite wall of the building (I think I still have the program source code somewhere, written in PDP11 assembler).
Having proved the technical feasibility, the company turned down the opportunity - the managing director was not into rock music and was worried about liability if the laser zapped the eyeballs of audience or of low-flying aircraft. However a few people left the company and started up their own laser light-show business (LaserPoint), and ended up doing shows for Jean-Michel Jarre etc.
The same laser deflection system went on to be used in various mapping applications, including emergency mapping to locate aircraft emergency beacons, but that's another story.
Regards,
--
Paul Hardy
ESRI Europe (phardy@esri.com)