Laser power

[elvis]

HI ALL

I know we have had several threads on the forum discussing the power of a laser projector system for visible beams etc.
My question is a bit diiferent here

i wanna know how does the power of a diode imapct the brightness of a graphic image on a screen.I know the wavelength of various colors do make a difference on the apparent brightness.

My purpose of asking this question was because someone inquired the other day if we can make billboards using lasers which would be as bright as neon light signboards and what level of powers of RGB would we need to create the same impact as that of neon signboards.Lets say to project a comapny's logo on one big wall of a building such that it is brightly visible even from some distance away .

thanks
elvis

[pelosh]

Hi.

If you would want to make a stand-alone billboard on side of the road and use rear projection technique, than 1-1.5W RGB should be sufficent.

I did this yesterday with my 3W RGB and cameraman had to take the video slightly off-centre of the screen...it was so brigt and clear, that camcoder's sensor was not able to process it when we put it right next to the screen. That was actually brigter than anything I have ever seen before..beautiful! And those colours!

Well, with the front projection it always depends on the surface you are projecting on to. If it is dark or uneven surface or if it absorb the light more than reflect it than in some cases 25W RGB would not be enough to simulate those neon signs.