Hi guys.

I'm trying to design a laser/mirror ball setup for use in a nightclub. Basically what I want to do is stick a big mirror ball (well, half-ball) to the ceiling in the center of the room, on a motor so it rotates, and place lasers in four corners surrounding the mirrorball (equally spaced from each other and the ball).

For the lasers I will be using laser-pointers. I will be mounting 3 or 4 lasers in a row in a project box. The number of lasers depends on what colors I can get hold of. They will be mounted inside the box, pointing out the holes as per the diagram. (Nothing to scale).

There will be one of these boxes in each of the four corners of the room. Each box will be pointed toward the the mirrorball, so that the lasers reflect off the spinning ball.

Now for the difficult part. The lasers all need to be made to flash. I want these boxes to have a selection of 4 settings, controllable from buttons in the DJ booth.

1. With each beat of the music, one random laser from each box flashes.
2. With each beat of the music, a random laser from each box flashes, at a rate of 8 random flashes per box on each beat.
3. The lasers flash in order from 1 to 16 at a rate of 10 flashes per second.
4. Lasers flash randomly, one at a time from any of the boxes, at a rate of 16 flashes per second.

My thoughts on this are that for settings 1 and 2, each box would have to have its own circuit board to control those functions, and for 3 and 4, a central circuit board would be needed. Or would it be possible to do it all with one central circuit board?

My real dilemma here is I have no idea how to do this. I'm well experienced at soldering, I'm just certainly not up to scratch on the whole circuit-making thing. Does anybody have any info, advice, or tutorials on how one would go about making such a setup?

Cheers.

 

I think you would have better results if you used focused, colored high-intensity lamp projectors. Laser pointers have such tightly collimated beams and are so low powered that you won't get the effect you're hoping for.

Your lasers being in a fixed position will reflect in a very narrow area. I'm afraid it will be a rather boring display after a few minutes.

The lasers that are used in light shows are much more powerful than your typical laser pointers. You can't see the trace from a red laser beam, unless you have a fogger going for the beam to reflect from. Green is quite visible, but comparatively expensive. Rotating mirrors can be used to steer the beams about, but that gets expensive too.

 

Cheers, SgtWookie.

I plan on using reasonably powered laser pointers (about 50 to 80mW probably). They don't need to be anything overly powerful anyway, mind, because we are only talking a 250 capacity venue, so its only small scale. As for the fogger, I already use two of them. As for the rotation mirrors, again, already have them on the mirrorball. The ball is custom designed with the mirrors not flat to its surface but all mounted at random angles, and the whole ball rotates on the vertical axis, so the angle of reflection of the beam is constantly changing.

Also, I have already tested this and I'm quite happy with the effect I get from it. The thing is that to test the system I've had to have a person standing in each corner holding the pointers, and I'd rather not pay 4 guys to stand in the corners of my venue and flash lasers about all night, lol.

 

This is an ideal job for a micro-controller, you'll also need a little circuit to convert sound/beats into pulses for triggering some of the sequences.

Take a look at the Microchip PIC 16F84, there are loads of example projects and tutorials out there. The code doesn't need to be complex for you requirements.

 

I think you should use high power green laser pointers.

 

How are you going to prevent potential eye damage to the patrons?
A reflected laser is just as dangerous as a direct shot.
Unless you can know for sure where the beam is going , I would reccomend a different light source.

 

The U.S. has some very strict regulations for using lasers in public performance. You might want to check Tasmanian regulations, if such exist.

 

There are regulations in Tasmania on use of lasers for whatever reason, not just public performance. Anyone can use any laser for anything up to a certain power rating. Once you get over that rating, you need a license to use it. ATM, regulations depend on what state you live in - there is no blanket rule for the country. The Aus gov't is trying to draft legislation for a national rule tho, coz too many kids are pointing their pocket pointers at airplanes.

Many nightclubs ban personal lasers, too. So if a performer supplies them as part of their lighting rig most allow it, but Joe Bloggs can't walk in off the street and start flashing his pocket laser around in the smoke.

As Gerty said, there is potential for eye damage. The way this will be prevented is simple - don't point the laser beam where it will reflect into the crowd. When it comes to light entertainment, there is always potential danger - smoke machines occasionally trigger asthma, strobes sometimes cause epileptic seizures, and lasers in the air above a crowd at times find their way to someones eye (or their eye finds the laser). The best we can do is minimize mishaps, lest we spoil the enjoyment of the patrons. The lasers I will be using won't be overly high powered, and they will be well below the power generally used in most clubs and events.

@ blocco a spirale: Cheers for the suggestions. I will look into the microchip. I'm not really up with that sort of thing, or circuits in general for that matter, but I know a couple of people who are that could probably help me out. That and I will hunt out some tutorials. I have a circuit at home from an old 12v car light that flashed to the beat of the music that I will try an integrate into the system to detect the beats.

 

Detecting the beat of the music can be accomplished with a low-pass filter. There are several "color organ" schematics on the net which activate lights in time with music.

The remaining features might be most easily accomplished with a microprocessor, especially the psudo-random features. Output from the microprocessor could then control the lasers via Darlington BJTs or via MOSFETs.

 

Not to rain on any parades, but wouldn't the laser produce just a little dot that would do nothing more than entertain cats for hours? Wouldn't you need a lens to spread it out and make it more "visual"? I'm thinking along the lines of the Aliens movie when the ship docks to the mining colony's vessel and the "scanner" is moved in to scan the ship with an elongated laser beam. That would give much more coverage when striking the reflective ball.

 

If the mirror ball is the kind I've seen in dance halls, it rotates. This would cause the dot to move. If there were smoke or mist in the air, the beam would be visible as it moved.

 

If the mirror ball is the kind I've seen in dance halls, it rotates. This would cause the dot to move. If there were smoke or mist in the air, the beam would be visible as it moved.

But it would just be a dot... I mean, that's cool and all... but I'm visioning a laser pointer dot just moving around a room, as if a screensaver were on the walls. Bar code readers create a "line" by moving the laser back and forth in a sine wave motion very quickly. This would produce some interesting effects.