View Full Version : What's exactly the frequency of LCD??

01-10-2010, 01:50 AM
Maybe stupid question, but when I tried to find answer from time to time in last 2 years, I haven't succeeded to make clear 100% right picture.

I am pretty familiar with vertical fequency in case of CRT's, I have 6 CRT's to 2 LCD's at home, you know :)

But what's the frequency in case of LCD's? I suspect it's closely connected with Vsync on graphic cards, that means the frequency is there just for the Vsync possibility as there is no refresh, the image is static. So VGA sends 60 images every sec, but the image is not really changed 60 times a second; it just lowers the lag due to the display shows the last picture coming from VGA when it finishes showing the previous one. Because I really think the LCD hardly can change the image 60 times a second, the crystals are not quick enough I'd say.

01-10-2010, 02:05 AM
AFAIK LCDs with a rated 60Hz refresh rate actually could refresh at that rate - but of course, as 90% of the pixels are instructed to remain the colour they were before, there is no change, the image looks static and you don't get eye strain.

01-10-2010, 02:47 AM
OK, thanks.

Another question is, if 25 Hz (or 50 Hz interlaced) was engouh for first TV's to make moving picture, why we actually NEED at least 100Hz displays for 3D? Is not 30Hz enough for every eye? It could flicker, but it should be enough to make uninterrupted stream where eye can't distinguish single picture. It is choice of consumer if the flickering matters, and if you look on the TV/monitor from some greater distance, it won't flicker so much (as it is with old CRT TV's).

Is there really technical problem or they just want people to throw away their year old LCD to buy the same but with double the frequency??

01-10-2010, 02:57 AM
3d has the image switch per eye so u need a minimum of 48hrz or 24 per eye but it dosnt work like that exactly since that isnt smooth so for high speed action to look smooth and not have motion blur u need atleast 60hrz per eye (60hrz is the accepted norm of peak human refresh, but i disagree) so thats were the 120hrz is but i dont think that thats high enough for an lcd since i need atleast 120hrz for todays lcds to not have motion blur (its still questionable though since there is no more blur but there are auras on some since the pixels are to slow) so what we need is 240hrz but a 240hrz input would take ridiculous storage and bandwidth.

i really wish death to the lcd, we need out rear projections back but its only economical in 60"+ ATM but i find it ridiculous that a $1100 50" mitsu beats every other tv of 60" or smaller and it costs about 25% of what a top end lcd dose of the same size /rant

01-20-2010, 06:10 AM
There's always LaserVision projection tv's if you are concerned you aren't spending enough with DLP :p