How the mW affect to the laser beam range ?

[boboweb]

Hello,

How important are the mW for the beam trow of the laser ? With other words does higher mW guarantee longer beam range and concentrate spot ?

Which is the best "thrower" under 50$ ?

Thanks !

 

[Asa]

Higher mW and lower divergence guarantees for longer range as opposed to the same wavelength laser with less mW and a higher divergence.

 

[chipdouglas]

but color and and how you perceive light also plays an important part. for some reason, my red appears to shine further into the night sky than my green. the red is double the power. but it also apears to shine further than my 445 too. and my 445 is a monster. so basically i don't have a concrete answer just some world observances LoL.

 

[ShaOwned]

A laser beam will continue infinitely, until it is stopped by something, because it is simply light. The divergence of a laser can tell us how the laser spreads, so the lower divergence that you have, the higher concentration of power per unit you will have for a longer amount of time.

But for the most part, from what I have experienced, if you shine a laser into the sky, it doesn't just suddenly "stop" somewhere in the universe. It's pretty much going to be a line forever. Therefore "range" for visual purposes is somewhat of a mute point. If you are working with something that requires a certain power per unit to be effective, however, range is definitely important, because at a certain point along the beam's propagating path, there will no longer be the required power per unit to accomplish the task you wish it to.

 

[daguin]

Also, different wavelengths are scattered by the air molecules at differing rates. "Perceived" as well as actual distance will be significantly affected by this.

Peace,
dave

 

[chipdouglas]

A laser beam will continue infinitely, until it is stopped by something, because it is simply light. The divergence of a laser can tell us how the laser spreads, so the lower divergence that you have, the higher concentration of power per unit you will have for a longer amount of time.

But for the most part, from what I have experienced, if you shine a laser into the sky, it doesn't just suddenly "stop" somewhere in the universe. It's pretty much going to be a line forever. Therefore "range" for visual purposes is somewhat of a MOOT (corrected spelling) point. If you are working with something that requires a certain power per unit to be effective, however, range is definitely important, because at a certain point along the beam's propagating path, there will no longer be the required power per unit to accomplish the task you wish it to.

please read post 3.

 

[ShaOwned]

please read post 3.

I have.

 

[daguin]

please read post 3.

I have.

Chipdouglas, you are observing what I posted about. Blue is MUCH more scattered by the air than red. That's why the sky "looks" blue. ShaOwned's description is correct IN A VACUUM. However, inside our atmosphere, light acts a bit differently.

Peace,
dave

 

[ShaOwned]

Ah. Very interesting, I didn't know that.

 

[chipdouglas]

ah ha!


michael

 

[agravlin]

Hello,

How important are the mW for the beam trow of the laser ? With other words does higher mW guarantee longer beam range and concentrate spot ?

Which is the best "trower" under 50$ ?

Thanks !

What in God's name is a trower, and how does one trow?

 

[boboweb]

What in God's name is a trower, and how does one trow?

I mean thrower

 

[qumefox]

To answer the OP's question though. If you want to see the spot at a very long distance, You want a laser with high power AND a low divergence. Longer wavelengths suffer less atmospheric attenuation, but at the distances being discussed, this is pretty moot. At distances where atmospheric attenuation becomes a strong factor, you wouldn't be able to see the dot yourself anymore anyway.

 

[loosekannonn]

there was a maritime experiment done hundreds of years ago,
on a foggy night a person in a row boat rowed straight out from shore.
on shore were a number of lanterns, each with a different colour glass around the flame.
we still use the colours today according to their visibility at distance.
in order from shortest to longest:

Green
Amber
Red

The Red lantern was the last one that was visible when the person in the row boat was farthest from shore.

this may help you determine which laser you will be able to see at distance relative to the out-put power.

 

[boboweb]

To answer the OP's question though. If you want to see the spot at a very long distance, You want a laser with high power AND a low divergence. Longer wavelengths suffer less atmospheric attenuation, but at the distances being discussed, this is pretty moot. At distances where atmospheric attenuation becomes a strong factor, you wouldn't be able to see the dot yourself anymore anyway.

The power and the divergence are important. What about the "color" of the laser ? Red or green is preferable for long distance spot ?

 

[davidgdg]

The power and the divergence are important. What about the "color" of the laser ? Red or green is preferable for long distance spot ?

Roughly speaking, green and yellow are the most visible, blue and red are similar (but it will depend upon the exact wavelength) and violet is the least visible.