Pixels, how do they work?

[nikokapo]

Title says it all.

How do pixels work?

What are they made of?

And why do they have an angle of view?


PS: I'm referring to pixels on i.e. an LCD screen.

 

[pseudolobster]

Liquid crystal has the interesting property of "twisting" (aligning into a specific crystalline structure) when voltage is applied. The LCD goo is sandwiched between two layers of oppositely-polarized glass so that in their neutral state the liquid does not pass light. When voltage is applied to a specific pixel via a grid, that section of liquid crystal "twists" its crystalline structure to allow the polarized light to pass through.

 

[nikokapo]

Good. But why do we have the problem of viewing angles?

 

[Bionic-Badger]

Depends on the LCD technology really. That's more a problem with TN displays than (S-)IPS or (P/M)VA type LCDs. The viewing angle problems probably come from the polarization that is required to allow or prevent light from exiting the display. If you're not directly in front of the polarization path you only get a partial effect of the polarization, muddying or outright changing the appearance of the resulting image.

If you want to avoid that, get an LCD display technology that is better for viewing angles like S-IPS or MVA, and avoid TN-type technology. The drawback can be slower response times, but that has been solved for some designs. The benefits of S-IPS and *VA technology is also that they have better color reproduction, so you'll actually be able to tell the difference between the greys on this messageboard for instance.

 

[GooeyGus]

so you'll actually be able to tell the difference between the greys on this messageboard for instance.

Hmm... I'm not sure what technology my monitor uses. Its a samsung 226BW, but for me there is a huge difference in the greys

 

[nikokapo]

[quote author=Bionic-Badger link=1214615393/0#3 date=1214638494] so you'll actually be able to tell the difference between the greys on this messageboard for instance.

Hmm... I'm not sure what technology my monitor uses. Its a samsung 226BW, but for me there is a huge difference in the greys  
[/quote]

Yeah me too :S. And i have a samsung 2253nw.

What i dont like is how LCDs reproduce gradient fills, they show them as BARS and not a full gradient, like CRTs

 

[pseudonomen137]

niko, this is the type of question wikipedia and google excel at . I try to only ask questions I can't find the answers to myself out of respect for others time.

 

[nikokapo]

niko, this is the type of question wikipedia and google excel at  . I try to only ask questions I can't find the answers to myself out of respect for others time.

I know I can go to Wikipedia. But most of the times the explanations of the members are really helpful in a way that I understand it better and they even explanate more stuff about the object or problem I asked. Also, you never know if anybody else has the same question, so I figure that somebody else could be interested in this. If you still find this is not appropiate please tell me and I'll stop doing it.

 

[Bionic-Badger]

If you paid $300 for your monitor you probably got a TN display.  They're good for gaming because of the fast response rate, but their color reproduction and viewing angle sucks compared to other screen techs.  That being said, it probably won't matter to most people, and most display colors pretty well these days, especially compared to whatever the person was using before.

For your gradient fills, if it's banding (that bar-appearance you described), then your display is probably a 6-bit color panel.  I'll explain what this means.  Your computer sends signals to the screen to be displayed as red, green, and blue intensities, which can reproduce virtually any visible color you need.  These color channels have 8-bit intensities, meaning they can each have 2[sup]8[/sup] = 256 levels of intensity, for 256[sup]3[/sup] = 16,777,216 possible colors.  If you have a 6-bit display, those channels only have the capability of displaying 6-bits worth of intensities, or in other words 2[sup]6[/sup] = 64, so about 64[sup]3[/sup] =  262,144 colors.  It also means that a 256-level gradient looks like a 64-color gradient.

For many people, it won't matter, but if you want good color reproduction on your screen, you might want to spend some more.  Here is a good buying guide, with continually updated models and prices for those who are interested.

 

[nikokapo]

If you paid $300 for your monitor you probably got a TN display.  They're good for gaming because of the fast response rate, but their color reproduction and viewing angle sucks compared to other screen techs.  That being said, it probably won't matter to most people, and most display colors pretty well these days, especially compared to whatever the person was using before.

For your gradient fills, if it's banding (that bar-appearance you described), then your display is probably a 6-bit color panel.  I'll explain what this means.  Your computer sends signals to the screen to be displayed as red, green, and blue intensities, which can reproduce virtually any visible color you need.  These color channels have 8-bit intensities, meaning they can each have 2[sup]8[/sup] = 256 levels of intensity, for 256[sup]3[/sup] = 16,777,216 possible colors.  If you have a 6-bit display, those channels only have the capability of displaying 6-bits worth of intensities, or in other words 2[sup]6[/sup] = 64, so about 64[sup]3[/sup] =  262,144 colors.  It also means that a 256-level gradient looks like a 64-color gradient.

For many people, it won't matter, but if you want good color reproduction on your screen, you might want to spend some more.  Here is a good buying guide, with continually updated models and prices for those who are interested.

Thanks, my monitor has an 8 bit intensity, but I still see bad gradients, I have it correctly configured (did all kinds of tests and configuration wizards). Maybe it's because I hate LCDs and I was very accustomed to my late loved CRT, who had 32bits of colour