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

Help reflecting a beam diffusivley.

Joined
Mar 2, 2012
Messages
18
Points
0
Hey guys,

I'm just trying figuring out how to reflect a beam diffusivley.

Here is an image to illustrate what I am trying to do;

Untitled.png


I'm not sure what material would be best for this kind of project.

Any help and or suggestions would be appreciated.

Thanks
 





jimdt7

0
Joined
Feb 5, 2011
Messages
1,893
Points
48
So what do you want to do,
reflect the beam back to the laser ?

Jim
 
Joined
Mar 2, 2012
Messages
18
Points
0
So what do you want to do,
reflect the beam back to the laser ?

Jim

I want reflect the beam back but a diffusive reflection. I don't want just the beam coming straight back to the laser.

It needs to spread out coming back as shown in the drawing.
 
Joined
Nov 7, 2008
Messages
5,725
Points
0
Hey guys,

I'm just trying figuring out how to reflect a beam diffusivley.

Here is an image to illustrate what I am trying to do;
[giant pic here]
I'm not sure what material would be best for this kind of project.

Any help and or suggestions would be appreciated.

Thanks

You'd have this effect simply by shining the laser on any unpolished white surface. By experimenting with the amount of gloss (starting with flat white) you can find the type of surface that works best for you.
 
Last edited:
Joined
Mar 16, 2011
Messages
470
Points
0
White panda board? you could use other growing aid light reflective surfaces test before you use, all of them I know can diffuse light but give off about 90% back at ya. I don't think mylar would work though, never fired a laser at mylar so IDK what would happen. "Poly" is useful if you are setting up a temporary grow room or don’t want to damage the walls. Poly is easily cleaned. The purpose of the black side is to not allow any light to pass through the plastic, which ensures your dark cycle remains dark. The white side is 75-90% reflective." truth is though its only a tiny % better than flat white paint.
 
Last edited:
Joined
Oct 19, 2011
Messages
173
Points
0
I saw somewhere that had rounded mirrors. If you wanted something highly reflective? Ill post the link if you would like, and if I can find it.
 
Joined
Mar 16, 2011
Messages
470
Points
0
I saw somewhere that had rounded mirrors. If you wanted something highly reflective? Ill post the link if you would like, and if I can find it.

would a round mirror not just reflect expanded but still colaminated(its a word right spell check said no) light?
 
Joined
Oct 19, 2011
Messages
173
Points
0
Oh nonono. Beam expanding is a whole subject on its own, that requires a positive lenses to unfocus the beam then a negative placed the right distance to refocus it. If you want your beam to just spread infinatly you will want something like this, 39MM DIA CONCAVE ALUMINUM MIRROR NEW/UNUSED - Surplus Shed this one is concave, convex would be ideal because it instantly starts spreading the beam, this one has a vocal length of about 10 mm. Which means it will focus your laser at around 10 mm then start spreading out.

On a side note, please read all your new favorite stickies on the laser safety section :) high power lasers are bad for your eyes, even if the beam is dissapaited out of its natural focused spot
 
Joined
Jun 3, 2007
Messages
2,560
Points
113
Oh nonono. Beam expanding is a whole subject on its own, that requires a positive lenses to unfocus the beam then a negative placed the right distance to refocus it.

You got lens placement backwards.
Galilaen beam expander lens placement. Double concave or plano-concave the a double convex or plano-convex
Laser ---- )(<<< () =====
Laser -----[(<<<[) =====

keplerian uses two positive lenses
A short positive focal length lens followed by a longer positive focal length lens.
Laser ----()>><<()====
Laser----[)>><<[)====
 




Top