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There is more to the motion blur problem than the slow transition times of LCD pixels. Newer monitors have much faster transition times and the problem is still there.

What I think is happening is that the CRT is producing a kind of impulse sampling of the moving image whereas the LCD is producing zero-order hold (square-step, see https://en.wikipedia.org/wiki/...) output. The human visual centers appear to perceive the "strobed" image of the CRT as smooth motion, the "change-and-hold" image of the LCD as blurred, even at high frame rates and with rapid pixel response.

The reason I say "kind of impulse sampling" is that the CRT does not flash a sequence of static images the way a film movie projector does. Rather, the CRT conducts a continuous raster scan, with a short blanking during the retrace. Each line of the image gets strobed at the time the scan reaches it, but each line is strobed at a different time instead of the whole image all at once as with a film projector.

I believe it is that scanning that accounts for the "soap opera effect" of video content recorded on video tape instead of on film. This is already a long while ago that a local TV station had a show-and-tell of this new thing called HDTV at our Engineering campus. The Engineering profs were oohing and ahh-ing about what they thought were amazing images, but I was pointing out the image artifacts (easier to spot in HD!) to the broadcast engineer from the TV station, and finding a receptive audience, he went on at length to explain the difference between Homicide, Life on the Streets, shot on video tape and having the soap opera look, compared with Law and Order, which he explained was shot on 35 mm film and then scan-converted for TV broadcast.

So, even if the CRT scanned mode of projection differs from the flashed-image mode of film projection, apparently recording the image on film, which records a sequence of still pictures, has a better look than video tape, even when film is played back on a CRT.

The other problem is that most people viewing video think that HD on a widescreen LCD looks fantastic and don't know what us motion-blur worriers are complaining about. This population includes engineers developing TVs and computer monitors. The only people complaining, it seems are hard-core gamers along with people who have seen the Kay 5500 Sonograph http://jproc.ca/rrp/sonagraph_..., a scientific instrument used in speech science that used a DSP to drive a CRT (at VGA resolution!) that produced a truly remarkable visual effect of a "voice print" rolling past the screen with zero motion blur -- the later software spectrum analyzers producing un-synched scrolls to LCD monitors of much higher frame rate look terrible by comparison.

With respect to the awful motion blur of LCDs, which other posters here is telling me in not cured by video interpolation, there is an element of what Robert X Cringely described in Accidental Empires, when (back in the day), a techie gushed about the desktop publishing revolutions, showing off the font quality of LaTeX printed at 300 DPI on a LaserJet II, which Cringely looked at in dismay in comparison to what the publishing industry got from photo typesetting.

DPI and frame rate are important, but if the community is at all serious about further advances in video, especially VR, engineers are going to have to take the physiology of human vision and the motion blur problem into account.

Motion blur on LCDs has been one of their weakest points for some time. Only in the last 2 years have some LCD models been released that utilize technology to reduce the amount of motion blur down to levels similar to that experienced on CRTs. I use LCDs for a variety of reasons, but I do miss the clarity/crispness of a CRT when playing fast paced FPS style games... Hopefully these solutions will continue to improve and become more mainstream.

Check out this page for some interesting details / comparisons:

http://www.blurbusters.com/faq...

This site is full of great information on the subject.

The main reason CRTs had such low motion blur is that the image persistence is much lower than that of a standard LCD (on an LCD without some of these newer technologies, each frame image is displayed for the entire frame duration).

> Can anyone really tell much above 30 fps?

Oh please. There is a MAJOR difference between gaming at 30 Hz, 60 Hz, and 120 Hz. I play most of my games at 60 Hz and can tell _instantly_ when a game drops to 30 Hz.

This is NOT limited to games.

OWE my eyes @ 24 fps !

Silky smooth @ 60 fps !

If you don't have a 120 Hz monitor and haven't tried LightBoost then you really don't even know what the hell you are talking about saying "30 fps is 'good enough'."

Some game devs are completely ignorant of the importance of 60 Hz.
* http://kotaku.com/5393106/inso...

Thankfully some game devs DO understand the importance of 60 Hz.
* http://www.gamespot.com/articl...

Please go read up on Temporal Anti-Aliasing if you don't understand why movies can get away with built in Motion Blur.

The reason LCD motion is blurry isn't because the response time or frame rate is too slow, it is because the image persistence.
Just take a look at OLED screens in the Galaxy S3 and S4. There is still a lot of motion blur despite near instantaneous response times.
They can solve this fairly easily with OLED by only displaying each frame for a millisecond or so, the only problem is that when you display it for a shorter time the image isn't as bright so they'll need to be a lot brighter during the blink.
See here for more information: http://www.blurbusters.com/demo-of-motion-blur-from-persistence/

> but an LCD doesn't go to black between refreshes so it doesn't suffer from flicker at any signal rate

That's not entirely true and misleading. I have an Asus VG248QE that supports nVidia LightBoost (even in 2D!) that inserts black frames between refreshes. Here is a video of the Asus VG278H that also supports LightBoost.
http://www.youtube.com/watch?v=hD5gjAs1A2s

Also see:
http://www.blurbusters.com/zero-motion-blur/lightboost/

> We perceive fluid motion as around 25-30 FPS so 60 FPS is perfect smoothness for movies and television.

You do realize that fighter pilots can detect motion up to 200+ FPS right? Yes, 200.
http://amo.net/NT/02-21-01FPS.html

I would _literally_ like to see hard evidence of movies shot at 60 Hz, 72 Hz, 96 Hz, 100 Hz, 120 Hz, and 144 Hz played back on
  a) CRT, and
  b) LCD with LightBoost
to determine what the minimum refresh rate needs to be. I know from personal experience that on a CRT my eyes MUCH prefer 100 Hz to 60 Hz.

> Having 120 Hz cables and monitors is really the brute force version of this, instead of motion blurring you just throw up razor-sharp images on the screen and let the brain do the motion blurring instead of the computer.

Agreed that is a "better" solution then blurring the hell out of everything at a low refresh rate.

> The only thing it improves is latency,
Yes. The other benefit with a high refresh rate is for gaming you can turn V-Sync OFF. As a gamer / drummer latency drives me nuts because V-Sync "on" lags input likes crazy. We're talking about 1 or 2 milliseconds here and it is annoying as heck.

> What I'm really waiting for is 100Hz screens without ghosting,

They exist already.

* Asus VG248QE 144Hz http://www.newegg.com/Product/Product.aspx?Item=N82E16824236313
* Asus VG278HE 144 Hz http://www.newegg.com/Product/Product.aspx?Item=N82E16824236293

The real breakthrough is nVidia's LightBoost mode which forces a black frame after ever rendered frame.
http://www.blurbusters.com/zero-motion-blur/lightboost/

The brightness is decreased by 50% but that's why the 248 and 278 are twice as bright as regular TN LCDs.

The Apple Cinema has slightly better colors (since it is an IPS panel) but I prefer the Asus 248 for 120 Hz gaming.

For those people who don't mind CRT's, but get eyestrain from motion blur instead, there's a new technology called LightBoost (google "LightBoost") which is essentially PWM at one strobe per refresh, with 92% less motion blur than regular 60Hz LCD (full order of magnitude less motion blur).

Competition gamers have been purchasing 120Hz computer monitors as of late, and enabling the LightBoost strobe backlight, to regain CRT like clarity; covered at the Blur Busters Blog - http://www.blurbusters.com/ -- which also has 60Hz versus 120Hz versus LightBoost comparisions available.

And TFTCentral's "Motion Blur Reduction Backlights Including LightBoost":
http://www.tftcentral.co.uk/articles/motion_blur.htm
They found that LightBoost greatly outperformed scanning backlights.

Obviously, this technology is not for flicker sensitive people, but it can be turned on/off, and it's another option on the market.

The best implementation is called LightBoost -- PWM at one strobe flash per refresh, for the CRT effect
http://www.blurbusters.com/faq/60vs120vslb (60Hz versus 120Hz versus LightBoost).

Also TFTCentral's "Motion Blur Reduction Backlights Including LightBoost" article:
http://www.tftcentral.co.uk/articles/motion_blur.htm

No, it has to be the same as refresh rate, or you get PWM artifacts:
http://www.blurbusters.com/faq/lcd-motion-artifacts