Will, Red, Green and blue lasers wen crossed create the spectrum we crossed ?

[JD1]

will, Red, Green and blue lasers wen crossed create the spectrum we crossed ??

hia,

if i get red, green and blue lasers, and cross them at one point, and change the intensity of each one accordingly, will at the point of where they cross, display different colours relevant to the mixture of said lasers, ??

Thank you

 

[tiny-tim]

hia JD!

yes, if you put a piece of paper where they cross, you will see white, or any other colour, the same as if they were separate dots on a photo or a tv screen

it has nothing to do with physics, it's just the way the human eye works

there are still only three wavelengths present, ie three different colours, but we see them as one colour, same as on a photo or tv screen

(if we had eye cells for each frequency, same as the ear has, then we would still see three colours!)

 

[JD1]

so if they were to cross in mid air, at that point of crossing, they wouldn't display the appropriate colour, they would have to hit something ? :-)

 

[tiny-tim]

yes, since there's no physical change, there has to be something for a human eye to see for the effect to appear

 

[JD1]

i see, so if a given space, however big by so big, was occupied with say a transparent gaseous material, would this suffice ?? :-)

 

[tiny-tim]

… a transparent gaseous material …

?? if you mean a gas, then say so!

(why use almost 30 letters when 3 will do?)

if you can't see the gas, then you can't see any colours either

 

[Drakkith]

i see, so if a given space, however big by so big, was occupied with say a transparent gaseous material, would this suffice ?? :-)

If the gas was transparent, then you cannot see the lasers, as the light must bounce or scatter off of something and make its way into your eye. If you simply point the lasers at a single spot on a surface, such as a piece of paper, you can see the different colors they produce as you change the intensities of each. You could also fill a transparent container with something like fog or smoke and get a similar effect.

 

[JD1]

Thank you both, :-)