Square laser grid

[magnus]

Hi guys.

Im struggeling with finding a lens that will project a square laser grid of around 10x10 to 20x20 square lines (not dots!) in the "hobby" side of the price range. I have found some suppliers that are more aimed at the professional machine vision market, and the lenses cost a couple of hundreds of dollars ++.

I have found one cheap model:
https://www.ebay.com/itm/GRID-lens-...900857?hash=item58e4cf1db9:g:0HQAAOSwQItUD4lY

Any other tips?
Thanks alot!

 

[BowtieGuy]

I'm not sure of the cost on one of these grid display units, but it's an option that includes more grids, 9 vs 4.

If you look closely, it's made up of many tiny dots, but it looks like the AixiZ is made similarly.

Edit: These laser grid projectors from "Laserglow" are very nice, but probably not in the price range you are looking at.

 

[magnus]

Hi BowtieGuy.

Ive been in contact with these guys, and unfortunately the cost is about 600 USD, which is too much for my hobby project.

I have also seen some LED grid projectors, which is stated to have a sharper image. The ones I have found are still too expensive for me.

I was hoping for something around 30 USD, but perhaps its unrealistic as this isnt something for the masses?

 

[BowtieGuy]

Hi magnus, I just edited my first post to include one from Laserglow, but it's around 10x what you're looking to spend. :cryyy:

 

[magnus]

Yea, those things are very expensive for some reason. I think the main reason is that they are used for industrial applications and they can take what they want for it, as 400 USD isnt that much compared to the whole system...
However the AixiZ one is just 5 bucks, so there has to be some other cheaper alternatives.
For instance these Ghostbusters use this unit for 55 USD : GhostStop Ghost Hunting Equipment - Laser Grid GS1 Ghost and Motion Detection System

 

[BowtieGuy]

That ghostbusters laser looks exactly what you're looking for; $59 isn't too bad compared to the other stuff out there.

 

[paul1598419]

I think the main difference is in the product. You only need the diffraction grating like AixiZ offers, but these others include a laser and mounting accessories. I would just search for a grid diffraction grating. By limiting your search to this, you'll weed out the more expensive options.

 

[Cyparagon]

I figured out how the ghostbusters laser is doing it. Any guesses? Hint: it is not a custom grating.

Answer will be posted tomorrow.

 

[ZRaffleticket]

Based on their pic it looks like a cross generation filter you put after the collimation lens... Just two in series with ample distance apart?

Shot in the dark from me, I don't know much about those lenses but that's what I'd bet on

https://www.ebay.com/i/382236502542...3D711-117182-37290-0%26rvr_id%3D1398108904892

-

Or aixiz has a diffraction grating... http://www.aixiz.com/store/product_info.php/cPath/46/products_id/148

 

[Cyparagon]

You were half way there. It is a cross lens in series with a regular dual-axis diffraction grating. In that order only. The line count of the grating determines the grid density. Positioning and rotation of the cross lens (which by the way is just a cylinder lens, which abruptly changes from Y-axis to X-axis halfway across the lens face) in the beam is crucial, as is the rotation of the diffraction grating.