Relationship between power and light intensity

[norbyx]

Hi,
I was wondering if someone actually measured the relation between power and light intensity. Personally I don't know if they are proportional or not. But from what I can visually see a 1W laser is not 10 times as bright as a 100mw or a 2W twice as bright as a 1W. So, since I am also a ham radio operator I thought that maybe it works a bit like the S unit in a radio, to increase 1 S unit you have to increase your power x4. So maybe a laser works in a similar way? 1W vs 4W twice as bright? I am just gessing here, may some expert be the one that explains me how it works.

 

[gazer101]

The light intensity grows at the same rate that laser power is increased. The percieved intensity by the human eye, however, does not. Percieved brightness exponentially decreases:

 

[norbyx]

So basically what I am saying is correct, in order to percieve a light intensity increese I need to increese the power drastically. Now the question is the following, is there some way to calculate the light perception increese in relation to the power ?

 

[Snecho]

Send a message to membet @Encap. He knows. Too busy to look it up unfortunately.

 

[Cyparagon]

Stevens's power law - Wikipedia

en.wikipedia.org

Or to simplify, increasing the power X times, means the perceived intensity is X^.5 times brighter. 4 times the power is twice the brightness for instance.