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



Laser Pointer Store

Multi Mode vs. Single Mode

RedCowboy

Well-known member
LPF Site Supporter
Joined
Jul 10, 2015
Messages
7,449
Points
113
Oh, just watched in the replay - quick hands :)

Still love how that 405 chews through 100 of them faster than the 2 watt needs for only 24. Divergence on the multimodes really is pretty terrible. When used within a few meters range link across a living room it doesnt seem too bad, but at larger distances it becomes quite ridiculous. At 50 meters out it's really just a line, nothing resembing a dot/circle.
Yes, bring on the 32x and the 64x blu ray burners.
3 watts of 405 would be more fun across the backyard than 10 watts of 450 multi mode.
 

olympus mons

New member
Joined
Nov 4, 2014
Messages
1,285
Points
0
Yeah I saw that video. Divergence really matters with experiments like these. Multimodes don't stand a chance against single modes or even DPSS up to a certain power.
What color baloon would be best for a 800mW 532?

I just ordered a hundred black balloons after seeing this but should have got orange I realized to use my 445 on. My 405 is only 300 mW. Probably won't do too much. That video is awesome I really want to try that.
 

Gabe

Well-known member
Joined
Jan 10, 2015
Messages
1,189
Points
83
What color baloon would be best for a 800mW 532?

I just ordered a hundred black balloons after seeing this but should have got orange I realized to use my 445 on. My 405 is only 300 mW. Probably won't do too much. That video is awesome I really want to try that.
Black is like the jack of all trades, it's absorbed by any colour. So blue laser to black is just as effective as blue laser to orange, in the same way that a red laser to blue is just as effective as red laser to black.
 

Teej

New member
Joined
Apr 16, 2014
Messages
1,296
Points
0
Flat black balloons would be the easiest "color" to pop, regardless of the wavelength of the laser.

A laser that has to be FOCUSED to the range intended to burn at, such as the 445 nm, is at a distinct disadvantage when the range to burn at changes w/o the laser being re-focused to the new range, etc.

I have a 3 w 445 for example that burns wood at 10' or so w/o a problem, well, other than the wife complaining about what I did to our deck...

...But not if I focus it to burn at 2', and then aim it at more distant targets, etc.

So it's really about different applications.


A line of balloons is more about show...lets face it, its the last one in the row, distance-wise, that is the limiting factor.

If it pops 1,000 to get there, or one, the display of popping ability can be left to the last balloon's distance...after that, it's just theatrics.


:can:
 

Benm

Well-known member
Joined
Aug 16, 2007
Messages
8,115
Points
113
Yes, bring on the 32x and the 64x blu ray burners.
3 watts of 405 would be more fun across the backyard than 10 watts of 450 multi mode.
I doubt we'll ever have more powerful blu ray diodes than currently exist, the optical disc is reaching the end of its lifetime quite rapidly.

One chance could be the development of true 3D optical storage systems that would allow far more storage in a compact form factor, but those seem nowhere near real world application for now.

As for the ability to pop balloons over a great range of distances without focus adjustments: that is just what coherent light can do: it will stay in a narrow beam for a long distance. If the challenge were to pop a balloon at some distance while being allowed to adjust focus you might as well use a xenon short-arc bulb and a big lens... or a sunny day and magnifying glass - you could rain down a kilowatt of light using a 1 square meter lens on a sunny day around the equator and pop a balloon, or melt a rock ;)
 

ultimatekaiser

Well-known member
Joined
Mar 10, 2013
Messages
2,832
Points
83
Makes me wanna do a balloon vid, I'd have to do it out on the sidewalk or something though :tinfoil: could bust out my green lab laser and see how many balloons I could pop with my >3W SM 532nm DPSS labby, since mine is not one of the crappy -near TEM00- versions.

SM diodes definitely are nicer for most uses in my opinion. But MM definitely has its place for keeping the cost down if all you need is the power at close range and dont care about the exact wavelength and such, like for certain types of florescence or in laser projectors.
 
Last edited:

Benm

Well-known member
Joined
Aug 16, 2007
Messages
8,115
Points
113
With 3W of TEM00 you could probably go for a record attempt (1000 balloons?) without too much effort, apart from inflating and placing all the balloons. You could easily test viability of this by placing a balloon 200 meters from the laser and popping that (assuming that you could line up balloons 5 per meter).

Multimode is great for practical applications where you didn't really -need- a laser in the first place, just a reasonably collimated beam of light at decent efficiency. One prime example of this would be video projectors that come with lasers, leds and even halogen lamps as the light source, but have comparable performance in terms of image sharpness (the halogen ones lose when looking at power efficiency by quite a big margin)
 

ultimatekaiser

Well-known member
Joined
Mar 10, 2013
Messages
2,832
Points
83
With 3W of TEM00 you could probably go for a record attempt (1000 balloons?) without too much effort, apart from inflating and placing all the balloons. You could easily test viability of this by placing a balloon 200 meters from the laser and popping that (assuming that you could line up balloons 5 per meter).
I never really considered doing just one at long distance, but I may try that. problem is that 3W will go a heck of a long way, so as mentioned above, I'd have to do it outside, which has its risks, and obviously it runs off the wall, its not a handheld. so that's not as easy to pull off. It is a fun thought though if I could have a private spot that had the required distance. I'm sure I could pop a balloon at quite a distance!

Multimode is great for practical applications where you didn't really -need- a laser in the first place, just a reasonably collimated beam of light at decent efficiency. One prime example of this would be video projectors that come with lasers, leds and even halogen lamps as the light source, but have comparable performance in terms of image sharpness (the halogen ones lose when looking at power efficiency by quite a big margin)
Pretty much what I just pointed out :beer: Its for when you just need the beam, but not necessarily with it in perfect quality/gaussian profile
 
Last edited:

olympus mons

New member
Joined
Nov 4, 2014
Messages
1,285
Points
0
I never really considered doing just one at long distance, but I may try that. problem is that 3W will go a heck of a long way, so as mentioned above, I'd have to do it outside, which has its risks, and obviously it runs off the wall, its not a handheld. so that's not as easy to pull off. It is a fun thought though if I could have a private spot that had the required distance. I'm sure I could pop a balloon at quite a distance!



Pretty much what I just pointed out :beer: Its for when you just need the beam, but not necessarily with it in perfect quality/gaussian profile
How far would you care to guesstimate?
 




Top