Why does a 1/3 blue, 2/3 black TV screen appear blue from a distance?

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When a TV displays a blue screen that is 1/3 blue and 2/3 black, the perception of the screen as blue is due to the functioning of the pixels. Each pixel on a Cathode Ray Tube TV consists of red, green, and blue phosphor dots, with only the blue dot illuminated in this scenario. The blue pixels emit light, while black represents the absence of light. Although the screen may appear predominantly blue, the black areas do not contribute to the visible light, leading to the perception of blue. When viewed closely, individual blue dots can be seen, but from a distance, the blue and black pixels blend, making the blue more prominent. The intensity of the emitted light from the blue pixels is also affected by the surrounding black pixels, resulting in a less vibrant blue than if the entire screen were blue.
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If the blue screen on your TV is only 1/3 blue, 2/3 black, why do we see it as blue?

(Each pixel on a Cathode Ray Tube TV is made up of 3 phosphor dots, red green and blue, so when you have a blue screen, only the blue dot is lit up).
 
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The blue pixels are the only ones that are giving off any light, so they are the only ones you can see. Black is merely the absence of light or color.
 
Drakkith said:
The blue pixels are the only ones that are giving off any light, so they are the only ones you can see. Black is merely the absence of light or color.

True, but when the TV is turned off I can still see the dark screen just as much as I can see the blue screen when it's turned on.
So why if 2/3 of the screen is black, the screen still looks blue?
 
frenzal_dude said:
True, but when the TV is turned off I can still see the dark screen just as much as I can see the blue screen when it's turned on.
So why if 2/3 of the screen is black, the screen still looks blue?

Get real close with a magnifying glass and you should see little blue dots. Since they are the only thing radiating (black is the ABSENCE of radiation) they are the only thing you see.
 
It has to do with resolution, if you get close enough you can see the individual pixels. When you are too far away the blue and black pixels were merge and only the emitted light from the blue pixels will be seen. The black pixels still have an influence, since obviously the intensity of the light will be less than when all the pixels would have been blue.
 
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