520nm super-safe beamer

Hey folks.

Many thanks to everybody for your kind support and help so far.

Me and a friend started our own company working on a project for indoor climbing. We use a laser-beam to show steps and holds for climbers. But there are many safety regulations and we don't want to harm people's eyes. Therefore we are constructing our own specialized beamer that will adapt it's output power for each stroke of the displayed graphic independently. So we will be certified in laser safety class 2. There are some projectors out there that are in the same safety class but they are extremely expensive and only used in construction. We have different requirements - this is why we make our own. But we'd love to get some feedback from you about it. What do you think? You can get more details and a demo video too here: http://www.geccoguide.com/demo-video/

We are also engaged in a crowd-investing campaign. That topic is quite new here in conservative Austria, but it works. If you are interested in more details or if you want to join by placing your own investment, let us know. More information: http://www.geccoguide.com/support/

Cheers

Matthias

Him, nice idea. Keen to see pics of your projector. What is the beam power in the video? It looks more than 1mW to me.

Yeah, we will post some pictures as soon as the design of the casing is done. The beamer in the video was from Tarm and had more power (5 to 20mW) and a widening lens. The intensity of the final beamer is of course much lower. But we tested it and the visibility of the green beam is still good then. Even better, for the human eye the lower intensity feels better. With the higher power people complained that the light is annoying then.

What a great idea! I used to climb a lot and this is a wicked application for lasers.

It looks like you know what you are talking about but some thoughts from me anyway, just in case they help (helps me learn too) :P

It's a good idea to use green as the eye sees it much brighter than other colours (I think blue is good too) with a lower power density.

I've just purchased a Coherent LaserCheck second hand from a forum member (awaiting delivery) for measuring audience scanned effects. One might be handy for you. It only measures 10uW to 10mW so not for measuring power of laser output. In the UK the MPE is 1mW for a static beam, so you would need to measure a static beam anywhere where people have a beam accessible to them and within 3m of the floor (although not sure what the equivalent would be with climbing) or 2.5m laterally.

If your lasers are floor mounted, this becomes a problem as the Nominal Ocular Hazard Distance is far greater. If the lasers are mounted high, then it could improve the situation (looks like you are ceiling mounted from the video?)
Energy density AND brightness from the source reduces according to inverse square law, so if you have 1mW close to the laser (when mounted low) by the time it reaches the climbing wall it may be VERY dim!

I imagine the climbing wall environment is pretty difficult to set lasers up in because NOHD has to be calculated carefully, estimating how people are likely to swing from ropes and measuring the beam from those positions, or otherwise calculating it based on known power at laser aperture and divergence.

I hope this project works out for you and sure it will. I've not seen anything like it and sure it'll be popular :)

Keith

Just wondering if you could achieve similar with a video projector.... Focus might be an issue.

Hey Keith. Hey Dnar.

How would you achieve the same with a video projector? We choose a laser beam because of the opening angle (field of view) and the brightness on daylight conditions. Nice side effects are life time, price and power consumption.

Keith, the beamer will be mounted on the ceiling or on a wall. But the certification test is done by authorities and the check is 10cm from the aperture. This is why we don't need to focus that much on distances or how people move along the wall or if they look into the beam. Thanks for pointing to the Coherent LaserCheck. We have a similar sensor in house already (but not from Coherent).

Mat

Hey Mat

You would have to spend an awful sum of money on projectors to make them visible in the sort of conditions usually found around climbing walls.


Have you tried a diverged 1mW/7mm2 beam yet?

I'm wondering whether manufacturing this device as a class II device is the best option. Is your company going to be installing them? A class II device will be limited to 1mW at the laser aperture, so light intensity on the wall would be considerably lower than having a class IIIR (5mW) at a distance from the wall and a blink-safe 1mW at the closest position that a climber can reach.

This may complicate things a little too much but some thoughts anyway.

Keith

Hey Keith.

True, the projector won't work under very bright conditions. But we tested all possibilities and all intensity levels on different material and different colors of the wall. Most of them are perfectly fine.

The certification for class II is done differently. Because the beam is moving (scanned), the output power at the aperture can be higher than 1mW, but if any point of the projected pattern is tested in 10cm distance from the aperture no more than 1mW is allowed. Unfortunately there is no scenario where you could use a class IIIR or IIIB device. In Austria you won't get an allowance for that and in Germany for instance you would need a trained security staff working there all day. This is impossible to realize. And usually it's not allowed to scan into the audience even if the projector is mounted in the ceiling 10m away. We as a company want to be on the safe side so that no one will sue us.

Mat

Not sure about your local regs, but here without an approved scan fail device (none are recognized) we have to work on the assumption scanning will fail, therefore static beams possible. This makes crowd scanning a big no-no, and this is what I would say your doing, crowd scanning.

Make sure you cover your ass. You currently rely on the beam scanning working to comply with safety regs....

That's interesting Mat. There are so many different rules around the world. I think the same actually goes here with audience scanned effects and class IIIR, although I've not looked into unsupervised permanent installations myself.

I hope things work out for you :)

Keith

We are including a scan-fail mechanism in the device and it's important for certification. Not sure if I can get that in UK or US, too. But we will at least try.

If possible, meet the US regs by going with an expanded beam. There is a precedent for it, Chauvet's FATBEAM devices. Proving out a scan fail here in the US will requiring hiring one of three or four consultants who specialize in this area.

Steve

This makes crowd scanning a big no-no, and this is what I would say your doing, crowd scanning.

Quote:

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Originally Posted by bruce741

This makes crowd scanning a big no-no, and this is what I would say your doing, crowd scanning.

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[something constructive]

There is plenty of precedent for laser guide-lights in manufacturing in the US, used to guide painting, making of cables, fiberglass layout etc.

ie Virtek Laser Solutions etc....

Steve