How Does a Movie Projector Show the Color Black?

Courtesy of Rhett Allain

But what about the colors from a video projector? It basically does the same thing. However, instead of a bunch of tiny RGB lights, it projects RGB colors at various points on the screen.

Projecting color black

Now we’re ready for the fun stuff. How does a video projector emit black light? Black light will be absent any Light, as we saw earlier. How do you project nothing? First, let’s consider a screen like a TV. If you have three small lights (red, green, blue), you can create a small black dot by turning off the lights for the three colors in that area. Boom, it’s black!

So, is it possible that you just turn off the projector to black? It can’t be right, can it? If that’s the case, you won’t be able to tell the difference between the projected black color and the screen without a projector. Yes, that’s exactly how it works.

Check it out: In the following image, I’m projecting a slide that’s half black and half white. The slide takes up most of the screen.