Playing with Lasers

It’s been a long week, up early and late to bed but the end is nearly upon us. Today was the practical side to the laser training, learning how to use the laser control system and putting into practice the safe programming techniques that we learned yesterday. Once again, it is one of those things that they can tell you how to do a million times but until you actually try doing it in practice, you will never really learn how to do it. The schedule for the day meant that before lunch, two people would have to program a single head show and one person a two head show. The more senior members were allowed to do the two head show and I was using the single head. We had about thirty minutes for the two of us to program our shows which should last the duration of the song we had chosen. It was a pretty big ask given that we had never before touched the control system and only one person could use it at a time meaning that in reality we only had about fifteen minutes each.

In the end it went fine and the most difficult bit was knowing what the laser would look like from the audience’s point of view as all you could see from the control stand was the final projection on the wall. Because of this, me and the other person using the single head controller spent most of our time making the final projections look nice not even considering what that would look like in the smoke. Although I didn’t get to see my show from the audience’s point of view, I know that the better shows used simpler things like flat scans (horizontal and vertical lines) and simple circles and circular patterns. This is because when reflected off the smoke particles it feels like you are being enveloped in a cone with the circular scans and the flat scans come crashing down through you which looks really really good.

After lunch the groups swapped round and it was our turn to do the safety side of things taking readings of the lasers brightness when it is at a point. Knowing these figures lets you calculate the safer distance and height so that you can minimise the potential risk of damaging eyesight. By ensuring the risk of a single point is below the guideline amount, any other effects you add onto that minimise the risk significantly. If you take into account the movement, rotation etc of the beam under normal operating conditions then you can reduce the risk by as much as 64 times and that isn’t including environmental factors like smoke.

At the end of the day we were treated to a three head laser display from the course leaders to the Star Wars theme tune. You can really tell that they have been in the business a long time because within seconds of taking control, the two operators were in sync with each other using patterns that had been programmed by us. I have no idea how they managed this but the result was amazing, maybe in 25 yeas time I will be that good!

We finished much earlier than I had expected and so I ended up wasting away the rest of the afternoon in the beer garden enjoying the nice weather we’ve been having. When I got back to my room though I was shocked to find it had reached a toasty 28°C! Walking up the second flight of stairs was like entering a sauna and so I spent the next couple of hours desperately trying to cool my room down before I had to head off to the library.

Sadly the final four hours of work were not enough to get the assignment finished and so I will be heading down to the lab tomorrow to put the final touches to everything. Each time I make a modification to the code, everything breaks. It then takes me half an hour plus to try and fix everything before making another change. The final modifications are necessary but it takes a deceptively long time to implement them.