Dot Brightness between lasers of different power?

[denodan]

I have noticed something strange?

I have a 50mW green laser, and now my DX200mW baton style focusable laser. Comparing both lasers seem to have the same brightness, but yet to test them in the dark.

What I have discovered is with glasses on looking at both dots, the DX200 have a smaller dot than my 50mW one. I would presume if the DX has the narrower and tighter beam it will seem about the same brightness as my 50mW one.

Goes to show to compare beams and the brightness of a dot can be deceiving. So presume the tighter the beam the less bright it may appear.

Is the generally the case?

 

[denodan]

Re: Dot Brightness between lasers of different pow

Tested the brightness at night, seems when the DX200 is warmed up the beam and dot is brighter then my 50mW green laser pointer, seems the DX200mW baton green laser takes a little bit of warming up to gain full brightnes.

 

[Things]

Re: Dot Brightness between lasers of different pow

Aha, another one!

OK, long story short.

I had a 40mw green module in my scanner. Now that was pretty bright, but not bright enough, I thought. So, I went and bought a 100mw CNI module. I compared the 2, full on. There was basically NO difference in the brightness at all! The CNI tested at about 141mw after about half an hour.

The thing is, our eye's sensitivity to brightness isnt linear. Once you get above a certain point, you will need ALOT more power for more brightness. It typically seems to be: 4X the power, for the 2X the brightness. So for your 50mw, you'd need a 200mw laser for the brightness to actually be twice as bright.

Kinda weird eh? I thought so too once I first discovered it.

 

[Switch]

Re: Dot Brightness between lasers of different pow

Actually the beam should be brighter if thiner. :-/ And so should the dot if smaller.Of course it's the same amount of light, so it will light up the room just as much if you point it at the ceiling.