Laser Grid - How?

[paul1598419]

No one has mentioned that using a mirror to project the beams from a diffraction grating downward would not give you parallel beams. They will continue to diverge like they do without the mirror. If you want parallel beams you will have to project then onto a surface, or use the other more expensive option mentioned by myself and others.

 

[Encap]

Not really clear what you want to do nor what the purpose for it is " Green laser gate/grid, as a portal, between two rooms, " that nobody is going to walk through or have their eyes exposed to potentially dmageing level of laser light? Is there any real purpose for such a thing?

If you want to do what is what the videos show--a serious quality effect-- you will need to fabricate long bars with as many lasers as you want lines either just up and down or crisscrossed to make squares---you say "Size of the grid 4x3m 13x9Ft " " Must be well visible, with light on, or at least suffused, no fog/smoke " so lasers strong enough for beam to be seen with light on---
For 1 laser every foot would need 22 lasers and 44 if every 6" if that is what you mean + you need a way to align them all perfectly so they are pointing in same direction in same plane and making equidistant lines.---figure $100 to $150 each for the diode, drivers and module + a power source or sources + whatever tools, mounting , aligning, and fixture costs---not a low cost project to make a credible grid of the type you want. Could easily become very expensive.
If it could be easily and cheaply done it would have been very many times over and efforts of others would be available to copy

What about where the beams terminate?--Will be a lot of very bright spots lighting up the area with a green glow.

Suggest you buy a 300mW green laser with active cooling--fan, TEC or both, a 12 volt power source for it, and a diffraction grid and experiment with it to see what it does and if what it does suits your purpose in the real world before you take on something like making multiple laser bars
For $80 to $200 --several choices here: https://www.ebay.com/itm/Focusable-...424074?hash=item43f9c7b6ca:g:rKAAAOSwImRYOCq7

If using a hand held pointer, consider how long do you want to leave whatever it is you put together "ON" .
Keep in mid you have to consider duty cycle, tine on vs time off, to avoid damage and/or burning out the laser, of any laser you decide to use.
For instance a Thor M2 1.6W 445nm blue pointer can only be left on for a minute or so, 2 min max before you have to turn it off and let it cool completely.
If you want to leave it on for extended periods of time look for a laser with a continuous duty cycle , good for running continuously.

You can have a look at this 3 projector laser grid "ghostbuster" low cost device for $169 and see if it suits you here: https://www.theghosthunterstore.com/product-p/puckgrid.htm

 

[Laserblast]

...If you want to leave it on for extended periods of time look for a laser with no duty cycle , good for running continuously.

Tnx for the Thor (edit: the price is rly good)

Good question ... I was no longer considering the switch-on time ....
I was thinking in the order of the hours, but...now i have to reconsider it.

If there are no other factors in game, other than prolonged heat exposure. I could add a liquid cooling system to the heat sink, but, if there is something else that could mess up the laser, when switched on too longs, i'm forced to think about, much shorter times.
I know that the diodes normally have a life span, around 25,000h even more if not overheated (so not my case)

I could even buying two. Turn them on and off with Arduino, to giving them some breaks.

 

[Encap]

Tnx for the Thor (edit: the price is rly good)

Good question ... I was no longer considering the switch-on time ....
I was thinking in the order of the hours, but...now i have to reconsider it.

If there are no other factors in game, other than prolonged heat exposure. I could add a liquid cooling system to the heat sink, but, if there is something else that could mess up the laser, when switched on too longs, i'm forced to think about, much shorter times.
I know that the diodes normally have a life span, around 25,000h even more if not overheated (so not my case)

I could even buying two. Turn them on and off with Arduino, to giving them some breaks.

Liquid cooled laser pointer or module Is a relatively insane daydream---would be at best expensive, difficult to accompish and problematical--nobody does or even offers anything like that for a lot of reasons except in the case a very high Watt power lasers. lol

TEC and fan cooling made for and integrated into diode laser modules made to be continuous duty/continuous running like in the whole page of 300mW green modules I gave you a link to is a already well proven, better, and lower cost way.

Pointer is not the way to go--especially cheap pointer--that Thor was just an example of a blue laser, low cost and quality.----
532nm green is about 10X as bright as blue and you will need as bright a possible---a 300mW 532nm green is as bright visually as a 3W blue.
The modules I put a link to are a better bet and many of them can run for hours/continuously.

Everything is possible in imagination, not so in the real world.
Nothing cheap or easy that is going to accomplish what you want to do unfortunately or it would have been done a thousand times over already by people who know what they are doing and there would be generally available pre-assembled and/or DIY parts for making such a grid.

If you want to buy a good quality laser pointer see: https://www.jetlasers.org/index.php and https://www.sanwulasers.com/

Good quailty new diodes , drivers for same, modules, and lens choices can be purchased here --if you want to investigate costs: https://sites.google.com/site/dtrslasershop/

 

[diachi]

No one has mentioned that using a mirror to project the beams from a diffraction grating downward would not give you parallel beams. They will continue to diverge like they do without the mirror.

Sounded to me like they were suggesting a mirror for each beam, that way you could adjust them all to make the beams parallel.

 

[paul1598419]

My guess is you are referring to post #7. I did read it as well as look at the diagram, but missed the (/some mirror) after the word mirror, somehow. My mistake. With the diagram and the word mirror, it is somewhat misleading, though.