Welcome to Laser Pointer Forums - discuss green laser pointers, blue laser pointers, and all types of lasers

LPF Donation via Stripe | LPF Donation - Other Methods

Links below open in new window

ArcticMyst Security by Avery

How much can 3d dichro's be adjusted?

Joined
Jun 30, 2008
Messages
1,660
Points
48
Im going to mount the L brackets that are on the 3d dichro's soon to the baseplate with a m4 screw.
I know for 100% certain it wont be perfect.

i just spend 3 hours to make the dot where to drill as perfect as possible. shut down and re-aligned about 5 times.
will it be enough? im almost certain there will be 2~5mm difference....wich will make the image on the wall alot more bad :(

So.... please answer ^^
 





Joined
Dec 1, 2008
Messages
878
Points
28
Once you mount it you cant really adjust your near field, so thats the part u want to make sure is 100% before you bolt down...

When I say near field I mean that you must have the dots perfectly on top each other on the dichros, the dichros then can adjust the FAR field.
 
Joined
Jun 30, 2008
Messages
1,660
Points
48
nice avatar.
but the dot you are drawing on the baseplate cant be 100% perfect...
or how do i know for sure where to drill?

any suggestions? i can have a white dot in 5 minutes now. i now where to put the dichro mounts. but i also know moving 0,1mm will make one dot move away and ruinin the white.
 
Joined
Dec 1, 2008
Messages
878
Points
28
I use tape to allign everything PERFECTLY at NEAR FIELD ONLY. Then drill and tap your holes.
Then after you have near field go back and allign so they line up at a distance.

If you look at my last dichro my beams line like this....
Untitledjjjjjj.png

Red is 635-thats why its square
1 blue is 445-thats why its elongated.
 
Joined
Jun 30, 2008
Messages
1,660
Points
48
I use tape to allign everything PERFECTLY at NEAR FIELD ONLY. Then drill and tap your holes.
Then after you have near field go back and allign so they line up at a distance.

If you look at my last dichro my beams line like this....
Untitledjjjjjj.png

Red is 635-thats why its square
1 blue is 445-thats why its elongated.

The moment i get white is when all the dots on the wall come together after leaving the galvos.
Looking at the galvos and dichros themselfs the dot are not on top of each other...
I dont really understand:S
 

anselm

0
Joined
Nov 22, 2010
Messages
2,448
Points
0
Instead of just drilling a perfectly circular hole, file or ream a "stretched circle" or slot, that way you can always
position adjust later on. Is that possible? Does it make sense to you?
 

vk2fro

0
Joined
Nov 30, 2009
Messages
1,304
Points
63
All my parts will be on mini base plates, and have the slots in them that anselm describes. You put slots in the laser mini baseplates perpendicular to the beam axis, allowing left right adjustment. Slots parallel to the beam exit on the galvos for fore/aft adjustment, and that way getting the dichros just slightly out wont matter - just loosen up that particular dichros's laser, and adjust it to match :)

As long as you get your primary beam centred (easy with the slots), lining up the other lasers wont be difficult. I'd be tempted to put a protractor (measuring gadget for angles - about 50c at the newsagent) on the base plate and mark 45° at each dichro position so you can get the angle spot on.

The slots would be VERY easy and quick to make with a 3-4mm round file - just pick a file the slightly bigger in diameter as your screws, clamp the piece in a vice and use the file. Once you've got a 2-3mm slot, turn the piece around, and work in the other direction. You'll end up with a 5-6mm slot in each corner, which will give heaps of adjustment should you be fairly way off with your dichro mounting. Another option is to drill two holes in the mini plate 3 mm apart, and file out the bit in the middle. Attach your laser / galvos with countersunk head screws.

The mini baseplates will also allow for really easy laser upgrades.
 
Last edited:
Joined
Jun 30, 2008
Messages
1,660
Points
48
well ive read this topic to late, but it doesnt matter.
i drilled them in the baseplate and they work fine :)

got a nice white color now :D
 




Top