Advice for a custom green pointer that is safe for eye exposure.

[Ableton69]

Hello everyone,

I've been quietly perusing the forum for years, and always found relevant information about lasers. I would be very grateful for any insight you can provide.

First a little backstory, feel free to skip the paragraph xD

I am based in europe and my work field is entertainment and stage lighting, and lasers are an integral part of it. I'm currently developing a show similar to the laserman show, but I feel very disconcerted with the handheld laser units that are being used. Recently I saw a show where the beams looked very nice and very thin with very little haze, and I got the hell out of there as fast as I could, because I talked to the guy backstage and he told me he got the whole system from AliExpress for a few thousand euros.
The handheld units, we are talking about 50mw - 150 mw 532 nm going for 30 - 40 euros a pop that arent probably even IR filtered.
(kinda like this https://www.aliexpress.com/i/32950848822.html?spm=2114.12057483.0.0.48476de6seGW7A )

So, what I want is a safe green laser (and a unicorn ) that if accidentally "scanned" into an audience, would not cause eye damage. The performer can make mistakes, and I would always sacrifice visibility for safety.
The unit needs to be very small with a body pack power supply.

My current unit is a 5mw 532 NM cheap laser pointer that I took apart. Since it had a click style switch, I soldered a flip switch which leads to an external 2 AA battery holder. As long as there is darkness and haze, it looks great. The modules are 2 years old now, and still working fine.
But I feel with the addition of other lasers (two RGB 3000 mw laser scanners with ILDA), they arent going to be able to keep up.
So, I have to ramp up the power.

My current (very very very limited) understanding is to use an expander to make the beam thicker.
I did some research online, and I came across this:

https://www.altechna.com/products/fixed-ratio-beam-expanders/

So, here are the questions I have:

Using the expander to get a thicker beam would really make it safer?
What other steps can I take to mitigate the risk factor to the naked human eye while doing so?
Using an IR filter for a 532 nm laser reduces eye risk?
Can you give me links to a high quality green laser diode with variable power output? Possibly compatible with the expander that uses SM1 mount.

I am quite handy in basic soldering and I am familiar with 3d design and printing, so I can make my own housing and parts to tie all the elements together.
Also I am willing to spend more money for quality products and safety.
My plan is to have the system wired up an ready, and to go have it tested and dialed back to safe levels.

And finally, am I asking for the impossible?

 

[steve001]

Hello everyone,

I've been quietly perusing the forum for years, and always found relevant information about lasers. I would be very grateful for any insight you can provide.

First a little backstory, feel free to skip the paragraph xD

I am based in europe and my work field is entertainment and stage lighting, and lasers are an integral part of it. I'm currently developing a show similar to the laserman show, but I feel very disconcerted with the handheld laser units that are being used. Recently I saw a show where the beams looked very nice and very thin with very little haze, and I got the hell out of there as fast as I could, because I talked to the guy backstage and he told me he got the whole system from AliExpress for a few thousand euros.
The handheld units, we are talking about 50mw - 150 mw 532 nm going for 30 - 40 euros a pop that arent probably even IR filtered.
(kinda like this https://www.aliexpress.com/i/32950848822.html?spm=2114.12057483.0.0.48476de6seGW7A )

So, what I want is a safe green laser (and a unicorn ) that if accidentally "scanned" into an audience, would not cause eye damage. The performer can make mistakes, and I would always sacrifice visibility for safety.
The unit needs to be very small with a body pack power supply.

My current unit is a 5mw 532 NM cheap laser pointer that I took apart. Since it had a click style switch, I soldered a flip switch which leads to an external 2 AA battery holder. As long as there is darkness and haze, it looks great. The modules are 2 years old now, and still working fine.
But I feel with the addition of other lasers (two RGB 3000 mw laser scanners with ILDA), they arent going to be able to keep up.
So, I have to ramp up the power.

My current (very very very limited) understanding is to use an expander to make the beam thicker.
I did some research online, and I came across this:

https://www.altechna.com/products/fixed-ratio-beam-expanders/

So, here are the questions I have:

Using the expander to get a thicker beam would really make it safer?
What other steps can I take to mitigate the risk factor to the naked human eye while doing so?
Using an IR filter for a 532 nm laser reduces eye risk?
Can you give me links to a high quality green laser diode with variable power output? Possibly compatible with the expander that uses SM1 mount.

I am quite handy in basic soldering and I am familiar with 3d design and printing, so I can make my own housing and parts to tie all the elements together.
Also I am willing to spend more money for quality products and safety.
My plan is to have the system wired up an ready, and to go have it tested and dialed back to safe levels.

And finally, am I asking for the impossible?

A beam expander could make the beam more hazardous depending on how it's used. There is a laser thing known as "Fat Beam" which is a better option.

 

[Ableton69]

Im not really sure what you mean by fat beam, what I mean by expanding is to widen a laser beams diameter to 8-10mm, end result being something like this

My doubt is whether a "fat beam" is safer then a thin one.

 

[steve001]

Im not really sure what you mean by fat beam, what I mean by expanding is to widen a laser beams diameter to 8-10mm, end result being something like this

My doubt is whether a "fat beam" is safer then a thin one.

I put "Fat Beam" in quotes and used capitol letters at the beginning of each word to indicate it's not a term I made up. Why did you not look it up to find out if this might be useful?

 

[diachi]

A better place to ask this question would be over on https://www.photonlexicon.com/forums/.

Show type stuff is better suited over there, more folk that know the rules/regulations/laws and can pointed you in the right direction to do it safely.

 

[Ableton69]

I did not in any way imply you coined the phrase.

And I did look it up, and "Fat Beam" as a lets say, technical term, only appears in promotional material of some of Chauvets line of lasers and a couple of dodgy chinese vendors, which to me looks like a laser beam that has been expanded with two optic elements, via Keplerian or Galilean method.

Do you have any information on how a fat beam is achieved, am I barking at the wrong tree here?

 

[Ableton69]

A better place to ask this question would be over on https://www.photonlexicon.com/forums/.

Show type stuff is better suited over there, more folk that know the rules/regulations/laws and can pointed you in the right direction to do it safely.

Thank you for the link!

 

[steve001]

I did not in any way imply you coined the phrase.

And I did look it up, and "Fat Beam" as a lets say, technical term, only appears in promotional material of some of Chauvets line of lasers and a couple of dodgy chinese vendors, which to me looks like a laser beam that has been expanded with two optic elements, via Keplerian or Galilean method.

Do you have any information on how a fat beam is achieved, am I barking at the wrong tree here?

I did not in any way imply you coined the phrase.

And I did look it up, and "Fat Beam" as a lets say, technical term, only appears in promotional material of some of Chauvets line of lasers and a couple of dodgy chinese vendors, which to me looks like a laser beam that has been expanded with two optic elements, via Keplerian or Galilean method.

Do you have any information on how a fat beam is achieved, am I barking at the wrong tree here?

No more than what you know. It could be simply be a beam expander, but if I recall correctly it's an

I did not in any way imply you coined the phrase.

And I did look it up, and "Fat Beam" as a lets say, technical term, only appears in promotional material of some of Chauvets line of lasers and a couple of dodgy chinese vendors, which to me looks like a laser beam that has been expanded with two optic elements, via Keplerian or Galilean method.

Do you have any information on how a fat beam is achieved, am I barking at the wrong tree here?

I don't know how either. It could be a beam expander. It might be an optic that evenly spreads the beam creating what's called a top hat beam profile. Beams typically have a bell shape profile as you know.

 

[Ableton69]

No more than what you know. It could be simply be a beam expander, but if I recall correctly it's an

ITS AN.... WHAT?!?!?!

I don't know how either. It could be a beam expander. It might be an optic that evenly spreads the beam creating what's called a top hat beam profile. Beams typically have a bell shape profile as you know.

I see, thanks I will look into that. Never heard of top hat profiles, lets see what I can dig up.

To be honest, I have 0.001 knowledge of laser physics. When I first used the pointers for an event, I found a guy that had a Laserbee tester to make sure we wouldnt blind anyone and called it quits. I wish i knew Leonard Hofstadter...

 

[smallfreak]

My current unit is a 5mw 532 NM cheap laser pointer

Did you measure it? „5mW“ and „cheap“ usually don‘t go together. They cheap ones usually have 50+ mW. They are labelled down to circumvent problems with marketing platforms and authorities.

 

[Ableton69]

Did you measure it? „5mW“ and „cheap“ usually don‘t go together. They cheap ones usually have 50+ mW. They are labelled down to circumvent problems with marketing platforms and authorities.

Yes, I made sure it was a unit where you can change the output via screw on the PCB. I found someone with a tester, I think it was a laser bee unit and stepped it down to safe levels. That service cost me more then the pointers themselves lol

The pointers are not directed in the audience, but sometimes there are reflectant surfaces, hence my quest...

 

[adalah]

Will be fun follow

 

[Coonie]

Best way to make a laser more visible without increasing power is a lot of fog. It'll make a 5mw 532nm laser insanely bright

 

[Ableton69]

Best way to make a laser more visible without increasing power is a lot of fog. It'll make a 5mw 532nm laser insanely bright

Yes and no, because fog actually makes it look dimmer. You need haze( you probably meant to say haze anyway), and even though it seems to be the same thing, its not.
Fog is thicker with particles that are bigger then haze, which in turn blocks the ray as it travels away from the aperture and blocks the line of sight as well. To top it all off, it dissipates fast too and triggers fire alarms... not fun!

 

[Coonie]

Yes and no, because fog actually makes it look dimmer. You need haze( you probably meant to say haze anyway), and even though it seems to be the same thing, its not.
Fog is thicker with particles that are bigger then haze, which in turn blocks the ray as it travels away from the aperture and blocks the line of sight as well. To top it all off, it dissipates fast too and triggers fire alarms... not fun!

Fog machine - Wikipedia

en.wikipedia.org

 

[Ableton69]

Fog machine - Wikipedia

en.wikipedia.org

Haze machine - Wikipedia

en.m.wikipedia.org

So yeah, there is a big difference. A good fogger is about a 120 euros, and a good hazer is 4 times that and up.