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

Divergence and apparent brightness

Exerd

0
Joined
Jan 2, 2010
Messages
448
Points
28
I'm sitting on the fence here...

I am ready to pull the trigger on another laser. All I have owned in the past is 532nm at 60mw or less.

I want to get something high powered, roughly 200mw. I like the color of the blu-ray laser, but I am curious to know how it looks in person when shined into the sky as compared to a 532nm.

Two things I'm curious to know:

What sort of divergence can I expect from a 405nm laser? (I plan on a custom build with glass lens if I go this route.)

As far as beam clarity and apparent brightness, will a 200mw 405nm beam appear as distinct and visible in the night sky as a 50-60mw 532nm?

Thanks
 





Asherz

0
Joined
Jan 18, 2009
Messages
1,623
Points
0
To answer your question about divergence, the divergence of a blu-ray as far as I know is equal to any other laser, as long as you focus it for distance pointing. But the beam may seem a lot larger than the green to your eye, due to the wavelength being on the border of visible light.

To answer your question about visibility, green light (532nm) is the peek colour of our vision, and will always seem bright. However violet light (405nm) is just on the border of the visible spectrum and will never be as bright as green is, but I am sure you will still be able to see the beam of the violet, similar to a 200mW red.

With a little reading you could of answered most of these questions your self :)
 

Exerd

0
Joined
Jan 2, 2010
Messages
448
Points
28
With a little reading you could of answered most of these questions your self :)

Thank you for the response.

I've been reading on the subject of lasers and visible light since 2004. I know that 550nm is around the peak of the human sight spectrum.

My problem is that I have no experience with 405nm lasers (never seen one in person). I knew that 405nm would not be as apparently bright as 532nm, that's why I chose the comparison of 200mw of 405nm vs 50-60mw of 532nm. :yh:

I have not been able to find a photo demonstrating a comparison of a high-power 405nm vs a lower powered 532nm shining into the sky, nor any photos demonstrating divergence. Actually, all I have been able to find is video of people lighting matches and burning electrical tape at 6 inches. :thinking: Yeah, I've found about a thousand of those vids.

I just wanted to ask for personal experience of how it is felt that they look against one another, as there appear to be a lot of people here with experience with both at a lot of different power ranges to give their thoughts on.

At this point, I'm still leaning towards a 150mw 532nm. The 405nm just appeals to me as a color more. Decisions, decisions.
 

Asherz

0
Joined
Jan 18, 2009
Messages
1,623
Points
0
I own a 150mW O-like module, and it is impressive. It burns tape, and the beam is amazingly bright :)

I don't own a 200mW violet, but a 110mW PHR build; It's a great build and I could imagine 200mW being a great burner and hopefully I'll get hold of one soon. If you haven't got a violet yet I would say go for it, the colour is very cool and it burns well as well :) And I'm sure the beam will be reasonably visible (like red.)
 

Exerd

0
Joined
Jan 2, 2010
Messages
448
Points
28
I own a 150mW O-like module, and it is impressive. It burns tape, and the beam is amazingly bright :)

I don't own a 200mW violet, but a 110mW PHR build; It's a great build and I could imagine 200mW being a great burner and hopefully I'll get hold of one soon. If you haven't got a violet yet I would say go for it, the colour is very cool and it burns well as well :) And I'm sure the beam will be reasonably visible (like red.)

I was actually sort of wondering about that 150mw from O-like. The other laser I had my eyes on was the 200mw advertised 532nm laser from them. Maybe I should grab them both together...
 




Top