Unit 2 Color: 1 of 23

If you had a powerful  magnifying glass, you could look closely at your monitor and you would see that the screen display is made up of lots of very small red, green and blue dots located very close to one another.  In a sense, the image you see on your  screen is actually three images displayed simultaneously.  For those of you old enough to remember, early color TV sets needed calibration often.  If you watched a repairman aligning the screen, the three color images would be displayed in turn, focused, and then aimed so that they exactly overlapped each other.  If the repairman did not get them properly aligned, you would see colored ghosts around the picture. (Image source)

Making a slight modification to our light bulb and dimmer analogy, on our screens we now have three sets of small light bulbs, one red, one blue and one green, located close enough together that your eye at normal viewing distances cannot distinguish them.  Our eyes perceive the light from the three bulbs as one and effectively mix them to form one new color.