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Q & A: Black and White Bulbs

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Most recent answer: 10/22/2007
Is there a light bulb which makes things appear only black and white (i.e. you don’t see color)? Or, is there something similar to it? Thanks!
- Ryan (age 18)
Cambridge, MA
Ryan -

No, lightbulbs work by producing light that is a mixture of different colors. Some bulbs, like red lights produce only red-colored light. But white light contains all of the colors. When you see an object, what you are seeing is actually the colors of light that are reflected off of that particular object. White objects reflect all of the colors and black objects reflect none of them. If you put a (normally) white object under a red light, it would look red since that is the only color of light that is there.

The only way to get a (normally) white object to look white is if you shine white light on it. But since white light contains all of the colors, other objects can still appear to be different colors (depending on which parts of the white light they reflect). To make things look only black or white, you'd have to force every object to either reflect all the colors or none of them - and you can't change the properties of the objects themselves.


(published on 10/22/2007)

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