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FrozenGate by Avery

laser brightness?

D

deathstarlaser

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ok so for laser brightness,,does the brightness of the laser dot double exactly with the mw? as 100mw green is 100x a 1mw green,,,,10mw is 2x 5mw? ect.... the laser brightness calculator says that but many say that part is not accurate.. and is it the same for the beam?
 





No perceived brightness is not linear.

Maybe rather than just necro'ing old threads, try reading them.

Lase
 
so how does it increase then? they did not come up with a clear answer...just how to calculate Raleigh scattering for different colors..
 
deathstarlaser said:
so how does it increase then? they did not come up with a clear answer...just how to calculate Raleigh scattering for different colors..
Click to expand...

Read This

That's the best answer that I have seen so far and covers laser brightness by colour. There is no real answer to your question as once a laser reaches a certain power the dot becomes far too uncomfortable to look at and your perception is skewed. This power level is different based on the colour of the laser and your own eyesight.

There are also links there to another thread where madmacmo explains the mathematics

Lase
 
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to be honest its all based on CIE tables if you look at the link I provided RHD has made a tool you can use and can also factor in Raleigh scattering.
 
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Comparing perceived brightness of a single wavelength the inverse-square law applies when talking about beam brightness, so 4x the power = 2x as bright. Again, this is beam only, not the spot on a surface.
 
ok those are good answers ...lol and sorry at first my computer was not letting me see the links for some reason
 
Using rhd's brightness calculator, why does it show that the brightness of say, a 60mW beam is twice that of a 30mW beam? shouldn't it only be sqrt(2)? since the power is 2x, the square root of that
 
It may be calculating your Raleigh scattering if you are selecting beam.
 
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John Capelo said:
Using rhd's brightness calculator, why does it show that the brightness of say, a 60mW beam is twice that of a 30mW beam? shouldn't it only be sqrt(2)? since the power is 2x, the square root of that
Click to expand...

rhd's Calculate Relative Perceived Brightness tool isn't 100% yet. Last I remember he was looking for something more reliable than the CIE tables to base his calculations on. There was also talk about accounting for photopic and scotopic vision.

Edit: Here's the thread on it (last post on 05-26-2011)

Lase
 
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The mark-1 eyeball. Brightness is a perception, and thus has no exact quantitative unit. It's just a formula we've agreed works well enough.
 
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