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Philips Working on LCD TV Ghosting
agentfive writes "Philips is working on a new lamp technology to eliminate ghosting. Ghosting is a problem in LCD TVs when tiny pixels creating the image take time to switch on and off and can't do it fast enough. The problem, widely recognized as the main drawback of LCD TVs, is apparent in fast moving objects such as tennis balls, but even slower moving images get fuzzy. Philips will do something similiar to a Cathode Ray Tube (CRT) by switching the fluorescent backlight on and off at a rapid pace."
They're ghostbusting.
Remove one of the advantages of LCD screens, why don't you?
This is the primary reason I would never buy an LCD TV. If they can fix the ghosting problem, I'd really appreciate it if they license their solution to other companies, rather than hoard it for themselves and pump up the prices, claiming that it's some sort of "XHDTV" or some such crap.
I am scientifically inaccurate.
In other words, to fix a barely-annoying problem with LCD displays they're willing to get rid of one of the greatest benefits. I'd rather deal with ghosting than have to go back to the days of CRT eyestrain.
I'll just stick to my much cheaper and only slightly bigger LDP TVs...
Who is this Karma guy and why is he bad ??
Isn't ghosting problem related to the speed at which crystals can reorient?
hilarious
Here's some real number for you. If the pixels can respond to any signal within 5 ms, that means the highest framerate that can be displayed without ghosting is 200 fps (1 / 5ms = 200 Hz). Which is more than you should ever need, and a big improvement on current LCD displays (a good consumer display has a ~20ms response time; 1 / 20ms = 50 Hz, not even 60 fps, but good enough for TV's 30 fps.).
I recently bought a 17" LCD monitor. It has excellent colour reproduction and I can't notice any ghosting even when playing FPS games. Is there any reason this same technology can't be used on LCD TVs without the need to make everything flicker? I can only guess that the cost is prohibative once you go beyond a certain screen size, but surely the larger pixel size of TV (as opposed to a high resolution monitor) would make fabrication easier.
Early LCD displays were bad, sure, but these days I use a CRT at work and a low-end 17" Advueu LCD display at home (on which I watch both TV and DVDs as well, in addition to gaming), and I can honestly say that the LCD's display quality--contrast, brightness, sharpness, lack of distortion--is far better than my Optiquest at work, and I haven't experienced anything even suggestive of a ghosting problem, whether while watching action films or playing FPS games.
STOP . AMERICA . NOW
FINALLY. Boy will I be glad when CRT technology becomes cheap enough to replace those dinky, thin, horridly outdated panel displays. Then we can fully realize the classic sci-fi television wet dream of dozens of small egg-shaped monitors placed mere fractions of feet apart to simulate a single, moderate-sized screen!
Come on people, get the terminology right. Ghosting and motion blur are not the same thing!
Ghosting is when you get a faint duplicate of the entire on-screen image, slightly offset from what it should be. I don't think this can even occur on LCDs, I think it is a CRT-only problem, but if you use crappy analogue VGA cables, then who knows?
Motion blur is what you thing ghosting is. It is caused by poor refresh times, more specifically it is caused the amount of time it takes for a pixel to become unlit, or "switch off". So LCD screens that have a poor response time often show a trail after a moving object that looks like a ghost of the object.
Understandable that you could get the two confused, but still wrong.
Well but when will wew see TVs using OLED technology. For sure they will be alot better than LCD counterparts.
So now I need to worry about my LCD's refresh rate in addition to its response time. That's fantastic!
People moaning about flicker, etc should realise that TV and monitor use differ alot, especially in viewing distance. So the flicker might be less of a problem, I would not expect them to apply this to computer monitors (although if I get a chance I'll ask some folk at Philips)
I agree, one of the main selling points of LCD's is the lack of eyestrain. This is a dumb move in my opinion.
While the pixels adjust their color, the backlight is off, and it will only switch on when the image is ready -- three times brighter than in a normal LCD TV to compensate for the dark period -- before going dark again.
Won't this make the flicker, oh, I don't know, about three times worse? I realize it's three times an LCD, not CRT, but still that seems like it could cause Pokemon-style seizures or something. Like you said, thanks, but no thanks.
I must admit that I've never even noticed this problem with LCD screens. Maybe I'm just incredibly unobservant, but you'd think that something that's known as "the main drawback of LCD TVs" would be noticable to even the casual watcher.
:)
When I saw the title of this article, though, the first thing that came to mind was this old TV that belonged to a club at my highschool. It was hooked up to a little camera on a remote-control robotic camera mount that a former club member had created, so the idea was that people sitting in another room could swivel it about with a joystick. Unfortunately, the mount broke, so the camera (which then became known as buttcam, due to its lowered position) ended up stuck looking in the same direction for some long period of time. This background image eventually got burned in somehow, and it got to the point where people could walk in front of the camera and appear transluscent on the TV.... and the end result was something that deserved the name "ghosting" far more than anything an LCD TV can do
great... so now that they have the ghosting problem 'fixed' next maybe they can work on contrast ratio and color accuracy, which to me is the bigger problem with both tv, computer monitor and projector lcd's (most decent lcd monitors don't ghost enough to be terribly noticeable).
contrast ratio is pretty craptacular on most lcd monitors, even the best ones. watching movies on an lcd you will notice that the black levels are almost nonexistent. for instance, a dark movie like the lord of the rings: the two towers is very difficult to make out the detail in the dark scenes. on a crt they come out fine, though with arguably lesser clarity (depending on the crt type).
color accuracy is pretty crappy on most lcd's as well (and that is being nice). if you are doing work on a project that needs to have proper coloring, don't use an lcd as your only reference as you will very likely have strange results when compared to a crt or if it is printed to film...
Large print giveth, and the small print taketh away
LCOS (Liquid CrystalOn Silicon) rocks. very fast, minimal "screen door" effect. Blows LCD and DLP out of the water.
I'd rather deal with ghosting than have to go back to the days of CRT eyestrain.
There are many reasons why CRTs cause eyestrain, and I'm not convinced flickering is one of them, especially today when most screens can refresh at 85Hz at 1600x1200, and even higher at lower resolutions.
Another problem is the cathode ray tube which by design creates a static electric field on the screen. This field will first attract dust particles in the air, which are then charged with the same polarity as the screen and as a result, they are shot from it, directly at the viewer, something which causes dry eyes. LCDs do not suffer from this problem.
Another problem of the CRT are the analog pixels, which are not perfectly sharp. They are smeared, because the graphics card cannot make abrupt enough changes between colours, and the neighbouring pixels are further smeared as they travel along the VGA cable. (Becomes really noticable at high resolutions and high refresh rates. The signal is pushing the bandwidth limit of the cable). They are also smeared because the electron beam used to paint the pixels is slightly fuzzy. As CRT-screens age, they may increasingly loose focus. Depending on your type of CRT age/price), the image may be blurred further by coatings put on to reduce reflections.
Our vision really dislikes not being able to focus on things perfectly. It puts a strain on the small muscles used to contract the lense inside our eyes.
LCD-pixels are perfect rectangles and does not suffer from these problems as long as a digital interface is used.
Today CRT-screens are superior when it comes to color reproduction, dynamic range. They are also superior when displaying moving images, because of their strobing nature. These new strobing LCDs may change this, something I'm excited about.
A witty
Silly moderator. Too bad you wasted a mod point on this retarded post. That really blows.
So, they're going to re-introduce flicker to deal with ghosting?
Doesn't sound like a win, IMHO.
-jcr
The only title of honor that a tyrant can grant is "Enemy of the State."
Secondly, the image loses color definition due to the backlight's frequency not necessarily producing the same amount of light pure color. Some times red may be better, some times green. If it gets really bad the a color can be completely skiped. Depends on the addressing method of course.
Thirdly if the addressing method prevents the color definition from being an issue as multiple colors are being addressed at once lines may appear over time, or the screen may noticeably flash.
Lastly there is some attempt to increase the power of white while flashing. This can effect the chromaticity of the white (read colors making it up) and make it biased toward yellow (usually). The brightness can also bleed through the black and make the over all contrast ratio suffer.
Now if they got it to work properly, good for them. I'd just rather not get the first model with this tech if I were you.
I'd say more, but my guild is raiding.
In TFA it says:...showed a flat TV that takes the idea of a Cathode Ray Tube (CRT) by switching the fluorescent backlight on and off at a rapid pace. This means that they take the idea of switching from a CRT and implements this into a flat TV, i.e. a LCD. And not the other way around. Can editors not read?
LCD / DLP / CRT / PLASMA / ??? / ???? / ?????
I prefer LCD over everything else at the moment, including DLP. I don't like the effect of the pixel being switched on/off the produce a shade, where LCD can be varible (control wise) to produce variable shades.
I have owned several projects since 1997. I've never owned a CRT projector, however I like the color on the LCD ones by far. I notice the LCD's don't last as long as DLP. I am using them for entertainment purposes, I'm not doing power point.
..the time it takes to respond.
Response times are generally the time taken to go from 100% to 0% - and this is generally the best case. Moving from 20% to 80% is a lot slower (source: arstechnica's ~recent lcd rundown)
0-100 rarely, if ever, occours in nature. (unless you're a cheetah!) The tennis ball problem, from green to yellow, is fairly small - 0dff0f to fdff28 was my guesses: big shift in red, green unchanged, slight blue. Even that big redshift would be reduced in real life.
So, yes, it's a problem. Whether giveing us 50/60hz flicker back is a good idea is, of course, another matter entirely.
Prediction for end of Universe #42: Fencepost error in Quantum_bogosort.cpp
The LCD I've been lusting after for months -- and that stylish Apple Cinema ripoff victims have been bashing -- is the Dell 24" LCD.
Power to the Peaceful
My ears are sensetive and I've never been able to get use to the high pitch whine from home theater style DLP projectors (under $1k). I use a Viewsonic LCD now and the quality is much better, not to mention it doesn't hurt my ears
Sumit
As it is, the cold cathode fluorescent lamp in LCDs doesn't last all that long. 50k-100k hours before it loses 50% of its brightness. Turning it on and off a lot does not lengthen its life. As with all electronic or electromechanical devices, the most amount of thermal stress you can put on them under standard conditions is to turn them on and off.
So what are we looking at with these new screens? Maybe half the already limited brightness half-life? CCFL tubes are not generally replaceable, even by technicians, and when the CCFL dies, you may as well throw the LCD in the garbage, because you'll never see it again.
Maybe Philips will make a user-replaceable CCFL module that you can just slip in and out?
Found a great side-by-side image comparison of the Dell 2405 vs Apple Cinema showing nothing but black. Dell wins.
Power to the Peaceful
Personally, I have never noticed ghosting on ordinary video files -- even action movies, which I've watched on many a dell 19" screen.
/me gets some more coffee.
The only thing that I have noticed ghosting on is while gaming -- but, since I only use good LCD's (do your homework!) the ghosting is barely noticeable.
What I'm left with, then, is a subtle, clean-looking form of motion blur in my games. Shit, some games steal my megahurts to create that effect! With an LCD, I get it for free!
Trails? Set them to OFF, MOFO! For I -- I have an LCD!
that is the annoying sound you're hearing.
Unitl you get a 3 chip DLP projector, there are moving parts (fan aside)
I think LCD has better color (personally) but the longevitiy isn't there.
What about images that are composed of unusually large pixels?
The last time I saw this technology was at the 2004 SID (Society for Information Display) show, in Seattle. LG/Phillips had one in their booth. I believe they were using LEDs for the backlights and were cycling rows of them in time with the LCD update. Being 60 Hz, the flickering was noticable, but the ghosting was completely absent.
Here's the problem: With a TV or movie screen, the image is flashed very briefly (on a TV, different parts of the screen are flashed at different times, but that's not important), and your brain stitches the scene together. The hold time on the image is VERY brief, so while it looks like a steady picture, it's really a succession of flashes with relatively long periods of darkness in between then.
With an LCD, on the other hand, you could say that the hold time is as long as the frame period (16 milliseconds or whatever). The LCD has no periods of darkness. With the CRT and movie screen, your brain is what stitches the images together, inferring the motion. With the LCD, you actually see the image change, and your brain perceives that as a smear. IIRC, what's happening is that persistence of vision is working against you and you end up seeing two frames at once.
Besides, raster-scanning the backlight, there are two other things that can reduce the smearing effect. One is to increase the frame rate. The higher the frame rate, the smaller the motion steps. It essentially reduces the hold time on each frame.
At the show, I went to a seminar by a guy named Kompenhouwer. For any device, you can mathematically model how it converts its input to output. This is referred to as a "transfer function". This guy developed transfer functions for the LCD and for a CRT and inserted a filter (It was really precomputed in software, but you could do it in real-time) between the video signal and the LCD that applied the CRT transfer function and inverse LCD transfer function. Those together cancel out the smearing effects of the LCD and make it look more like a CRT. For static images, the filter does nothing, but as I recall, the effect of the filter on motion is to amplify the high-frequency components of the image in the direction of motion. I think that as long as you are tracking the motion of the moving image with your eye, it looks right, but if you don't, it looks weird (but I may be remembering that last bit incorrectly).
switching the fluorescent backlight on and off at a rapid pace.
I'm no expert but aren't fluorescent lights already off 99% of the time? It's just the way it has to be because of its design and the gas in them.
I hope these new displays fail horribly. This is the LAST thing we need...
Modern LCDs have response times so low that the problem is nearly eliminated. Further developments such as overdrive (Increasing response times by going past the desired setting and then back again) have further improved it.
So, WHY are they going to go and introduce flickering LCDs?
This is like hitting someone on the head with a hammer in order to kill a fly. The "solution" is way worse than the problem.
I believe it was in "Accidental Empires" where the author is amused by some geek trying to tell him how great a LaTeX manuscript looked. To the author, the Computer Modern font rendered on a 300 DPI laser printer looked like a blurred mess, especially compared to a book done on a photo typesetter, but to the geek, the LaTeX output and the typeset book were indistinguishable.
Look people, there are vision psychology issues with rendering motion on LCD screens, and you all may swear how you like your LCD monitors and even do gaming or view videos and "can't tell any blur compared to a CRT", but there is a big difference, and when there is a big push to make LCDs consumer's primary way of watching TV, there is going to be a problem, and it is encouraging that at least someone at Philips is aware of it and looking into ways of dealing with it.
I came across the motion blur problem because I write software to do digital sound spectrograms or "voice prints." The gold standard for this type of display is the Kay 5500, DSP-based hardware that displays a rock-solid voice print scroll on a VGA monitor -- you may have seen a Kay 5500 on one or other TV crime drama where they "analyse voice prints" to try to pin an answering machine threat on a suspect.
You can do a Kay 5500 type display in software, but it requires synching the scroll to vertical retrace. Once you get such a display, it looks great on a CRT, but it looks like absolute blurry mush on even the fasted-responding LCD.
I tried every which way to scroll an LCD display to get a smooth camera pan effect. Failing that, I tried to rig a CRT to look bad like an LCD. If I set the refresh rate of the CRT to 60 Hz, the scroll looks fine, although the display is quite flickery. At a refresh rate of 120 Hz, the scroll looks great and the flicker is gone. If I run the refresh rate at 120 Hz but repeat the frame for two refreshes, scroll the scene, repeat the next frame for two refreshes, simulating an LCD at 60 Hz, it looks muddy, just like an LCD.
Well, it seems that Philips knows that you have to strobe the image to get a good scroll/pan/motion effect. A movie camera/projector strobes the image; a CRT strobes the image in a kind a progressive-scan sort of way; a CRT holds an unstrobed image, and changes the scene. It is like the difference between an impulse-sampled and a step-sampled D/A.
I wish Philips every success with their strobed LCD. If the Philips technique works, I know I am buying a Philips if I get an LCD HDTV.
Comment removed based on user account deletion
I never knew that Cathode Ray Tubes used a fluorescent back light!
Adding a flash to the screen will make watching them tiresome. LCD's advantage in readability is the eye does not have to adjust to flickers that TV/Cathode Ray Tube use for persistence of vision. Over time the eye catches the blank spots, the variations in brightness and the pupil contracts and expands to match. LCD has a steady light. I recently started using an LCD screen at work, and I have no intention of going back to a CRT again. My eye strain issues are gone, I walk out of work not feeling tired. I plan to chuck my old model TV soon for an LCD ASAP, and if Phillips is planning to use flicker technology I won't be buying one.
Sorry about the writing. Robot fingers, you know? Cliff Steele in DOOM PATROL #23
As you know, the response times usually handed out are the time it takes for a pixel to go from black (0) to white (255) or white to black. LCD pixels can do this much faster then they can go from black to grey (128.) Another interesting attribute of LCD pixels is that they can go from white to grey faster then black to grey.
Some new LCD panels take advantage of this knowledge. To turn grey, it will push the pixel to full on, from black (0) to white (255), and then back down to grey (128)- and the whole process takes less time then going from black to grey. Unfortunately, in some circumstances you can see it and it might produce a "sparkle" effect on the video. But it's not distracting.
Anyways, to my original point, manufacturers are recording the response time from black to white, which isn't generally representative of the real performance of the LCD, which may be dismal when going from white/black to grey, or even grey to grey.
However, there's been advances in the manufacturing process and many new LCD screens reduce the ghosting to "can't even notice it" levels even without using tricks.
Friend of mine has a Samsung 19" LCD screen that claims 12ms response. I have a 24" HP 2335 widescreen that claims 12ms. My screen is a gem - it's an underrated screen for the price (You can get them new for $800) and it's in the "can't even notice it" category. Meanwhile, the Samsung is difficult to use for fast paced FPS type games.
I guess my point is that even though the manufacturer might claim 8ms or 10ms or 12 - they might not be bullshitting =) It could be a really awesome screen. But the only way to tell is by actually using the screen, because the current system of measurement doesn't take into account the TTG - time to grey.
- It's not the Macs I hate. It's Digg users. -
and they also don't have a "native" resolution crippling every other resolution that requires interpolation to display.
that and ghosting will never go away.
the best lcds have a 25ms response rate (not the bullshit 8, 12, 16 that manufacturers like to lie about) and that's not enough to get rid of ghosting. so they resort to tricks and say that the response rate is now 8ms.
lcds certainly have their place. lower power use, sharper (generally) displays, digital addressing, won't cause hernias for weak nerds/geeks, takes up little desk space.
but for people like me that can lift 22inch monitors and appreciates high end crts for gaming, i cannot make the switch to lcds. not to mention a high end lcd costs over twice as much as a high end crt.
so as the saying goes, the right tool for the job.
i'll continue to use crts for the foreseeable future. maybe OLED or some other technology can finally replace all the features that make crts great and have the benefits of lcds at the same time.
Science : Proprietary , Knowledge : Open Source
not to mention a high end lcd costs over twice as much as a high end crt.
They did in 2003...
Now you can get a moderately high end (DVI, multi-inputs, 12ms response) 21" LCD for $500 or less while the equivalent 22" CRT costs considerably more. As of early 2005, quality LCDs are cheaper than quality CRTs. Of course this is mostly because there aren't many quality CRTs being made anymore, but that doesn't lessen the point.
I can't measure that my display is really 12ms, but I can tell it ghosts way less than displays I've seen advertised as 25ms. I'd like to know how you prove that it's 'bullshit'.
perhaps you'd want to use a crt with 100hz or more at the resolution you want to use. hence a high end crt. you were probably using a 99 dollar pos that could only do 75hz.
anything under 100hz flickers for me but i never get headaches.
anyway, try using a high refresh rate next time and see if it goes away.
Science : Proprietary , Knowledge : Open Source
12ms is some marketing figure mostly.
maybe under ideal conditions and other narrowing restrictions, do you ever see a 12ms response.
if it were a real 12ms lcd, it would uniformly and under all conditions respond at least within that threshold.
they also lie (read deceive) about viewing angles of lcds. this one is much more well known among lcd afficionados. probably a lot of other things, these just are the ones i remember atm.
lcds and crts aren't perfect but they each have their uses. i'm gonna wait another 5-10 years before lcds don't suck as much as now. cause it's already difficult to find good crts now... i can only imagine it getting harder in the years to come.
Science : Proprietary , Knowledge : Open Source
That's a case of solving a problem that affects less than 1% of the population (Your specific application where ghosting/motion blur is actually a problem, as opposed to 99% of the population for whom it's been solved adequately on any decent LCD made in the past 5+ years.) in return for bringing back a problem that affects 25-50%+ of the population (flicker-induced eyestrain and headaches are extremely common) and produces SEVERE health risks for a non-insignificant number of people.
retrorocket.o not found, launch anyway?
The two monitors share the same Philips LCD panel.
It's not called ghosting. It's called "motion blur". Scroll about halfway down and look at what some Anandtech writer just wrote about the whole subject:
d =40&threadid=1648775&enterthread=y
http://forums.anandtech.com/messageview.aspx?cati
HJ
It's currently available for $779, the lowest price ever. The 2005FPW, which I bought for ~$500, is also available for an all-time low of $389. Fscking Dell.
The monitor is *awesome*, BTW. Love the rotating base and USB hub. I've made more use of both than I thought I would. Ghosting is no big deal; I watch movies all the time and I've never had a problem.
Its been done already just not with the flourescent backlight but withwhite and RGB color LED backlighting. LED backlit LCD's with no flicker or fuzzy images have already been demo'd
My friend who is an optometrist has told me the major reason why CRT monitors give you eyestrain and eventually damage your eyes is because of the thickness of the glass.
The image is projected onto the inside of the glass tube, which is nearly 1cm thick.
Your eyes are continually shifting focus between the front of the glass, and the back (where the image is).
Keeping your monitor clean helps a lot, as it stops the eye focusing on the front of the glass so much (less grime to focus on).
LCDs have glass that is very thin, so you don't get eyestrain
I mean, wouldn't there still be a choice between the type that eliminates ghosting and a regular LCD? I don't see it as a problem, as long as there's still that option. Well but when will wew see TVs using OLED technology. For sure they will be alot better than LCD counterparts. I fully agree; I can't wait either. OLED's are so much thinner, they're flexible, they use much less electricity and they're cheaper to make. It will truly improve all aspects of video and picture technology.
and they also don't have a "native" resolution crippling every other resolution that requires interpolation to display.
Sure they do - it's just always in some shitty, interpolated mode, so you don't notice. Do you think that the number of physical dots on your screen changes when you change resolutions? It doesn't, it just mishmashes and overlaps them to fit the new resolution. CRTs have a fixed dot pitch, and I highly doubt you're running a 1:1 relationship with them.
so they resort to tricks and say that the response rate is now 8ms.
I'm typing this on a 27" LCD Television (which looks superlative, btw), and have watched a number of action movies, and played games on it, with absolutely zero complaints. The ghosting issue is such a holdover of 1999, and every half-wit, still trying to defend why they can't affort a new LCD display, imagines that they see ghosting all over the place on LCDs, while they carefully block out the same ghosting that occurs on all medium or long persistence phosphor CRTs (which is every high end CRT, humorously enough). Keep on convincing yourself, though.
what would a "real 12ms" be? the fact of the matter is that the response of an lcd is too complicated to sum up in a single metric.
The latest lcd panel is 4ms and is in fact 4ms. Look at this graph produced by THG Showing the pixel intensity changing from 0 to 210 in 4.3ms but since the requested value was 175 they dont count it as 4.3ms instead they wait until the pixel is 178. Now the mfg figured out how to get the pixel to change in 4ms they are damn well going to slap 4ms on the box.
It's not a lie it's just a semantic. Tom's tells you that it is more important that the pixel be within 10% of the requested value before it should count as having changed at all - now that's a lie. Your eyes do not notice the pixel being 210 instead of 175 for 4ms, your eyes notice the complete and utter lack of ghosting.
bite my glorious golden ass.
if it were a real 12ms lcd, it would uniformly and under all conditions respond at least within that threshold.
So basically you just invent whatever nonsense you want to justify your unfounded beliefs. Alrighty then.
In the real world the VESA consortium set standards on how they would measure response times, with strict conditions under which it would be measured. Now I realize that you're an authoritative voice, but I think I'll trust the labs a bit more than I trust you. Anyone who has actually been involved with LCDs for the past 6 years or so would say that you're full of shit, given the vast improvements that have happened with LCDs.
they also lie (read deceive) about viewing angles of lcds. this one is much more well known among lcd afficionados
So basically one has to signup to the cult to get the "inside scoop", right?
It is interesting that LCDs have some real deficiencies that you totally ignored, such as a subpar dynamic range, and limited colour saturation and fidelity. Instead you go for some nonsense conspiracy theory balogna.
The movie camera along with the movie projector work on the principle of freeze-framing a segment of film, strobing that segment with a shutter, and then advancing the film to the next frame segment. That has the effect of flashing a still image, blanking the image, and then flashing a still image of the next frame. This famously flickers -- movies are not called "flicks" in slang for no reason -- but it is a particularly good way of representing scenes with motion in them that must work on some aspect of the physiology and neural pathways of vision.
The video camera and the CRT video monitor work on an entirely different principle. There is no shutter and no freezing of the image -- the image is continuosly scanned in a progression of horizontal lines. The CRT video monitor is also a good rendering of motion -- the combination of a video camera and CRT monitor, however is not. A lot of the "higher production values" TV shows are shot on film, scanned on to video tape, and then broadcast to get the motion sampling effect of the movie camera for better motion rendering among other effects.
The LCD may be far better tech for being parked in front of a computer monitor viewing source listings for 8-10 hours a day. When the LCD gets into people's living rooms when the HDTV deadline is approached (was it pushed back?), there is going to be a different group of people viewing entirely different content, and I am telling you there are going to be dissatisfied consumers viewing motion-blurred HDTV mush who will want their old TVs back.
My scrolling voice print application isn't even 1% of the population, but it has given me a perspective on viewing motion on LCD monitors. Very few movies or TV shows have steady pans -- the motion is usually confined to small portions of a scene. But there is something "not quite right" about TV viewed on LCD screens, and if you study the scene carefully, you will notice the motion blur.
As to flicker, I consider myself flicker sensitive -- I can see 75 Hz refresh as blinking away -- but 100 Hz or higher refresh is clearly available technology and looks rock solid as far as I am concerned. As far as motion blur, everytime I scroll text in an editor window, it is a mush of unsynched motion blur, but it does not have to be. We have enough computing power to smooth scroll editor windows if we want to -- DEC used to have a glass terminal that smoothed scrolled -- this would require vertical-retrace synched mouse events to pull off. Why don't we have that -- is the geek community so very happy with blurred text scrolls?
Anyway, some dudes at Philips are experimenting with an LCD version of the movie projector as a good way to represent blur-free motion. If they market it, you will be able to go down to Sears and view the Philips LCD side by side with the conventional LCD and as a consumer decide for yourself whether the crisper motion is balanced against flicker and whether you like the conventional LCD better. No one is pulling your conventional LCD computer monitor from the market.
It sucks great steaming tourdes during the day, but at night- it's a fuckin' MOVIE THEATRE.
Take your dinky LCD home with you, please.
RS
Shoes for Industry. Shoes for the Dead.
"Remove one of the advantages of LCD screens, why don't you?"
You obviously missed this. It will only turn off and then on again if there is a color change. WHAT A CONCEPT TO TAKE IN?
While the pixels adjust their color, the backlight is off, and it will only switch on when the image is ready
The human race is artificial intelligence created using object orientated programming.
I can see the ghosting and I can see the flicker.
(CRT flicker and LCD ghosting) and I don't care.
This could be a problem for Philips for a lot of reasons.
People have a problem lumping an entire class of product together and "Once you've seen one duck you've seen all ducks".
I've seen it in Linux and SUVs.
Every Linux distro is diffrent and SUV is a class of vehical refering to many diffrent types of vehicals, Vans, MiniVans, Trucks, Jeeps etc.
But people think all SUVs are alike, all Linux distros are alike.
They also think all LCD TVs are alike. It's difficult to get most people to appreceate the diffrence in quality between a low end wide screen and a high res wide screen.
With LCDs people just think it's there. If you fix it by adding filcker people will get the idea that all LCDs flicker... and have ghosting. You'll have a hard time convencing anyone that there is a tradeoff.
Way back in the day I had a Sony Trinatron TV for a computer monitor. A friend noticed the guide wire and desided to ask me why do TVs have that.
My other computer uses a Zenith monitor (not TV) seeing that my Zenith didn't have the wire he concluded it was a diffrence between a TV set and a computer monitor.
It took me a while to get him to understand this was unique to the Trinatron.
Thankfully I had a Zenith TV in the living room for watching TV. Thow for the first 5 minuts he sware he could see the wire on it.
I don't actually exist.
No you didn't.
name the manufacturers that strictly adhere to the "vesa" consortium guidelines?
no sir, marketing is legal lying.
when the industries as a whole start to behave more responsibly, i'll give them the benefit of the doubt.
everything i've read on the subject tells me that way too many manufacturers distort these metrics. they want their products to appear more attractive than they really are in order to increase sales.
if you don't want to believe that, you are entitled to that. as am i.
and trying to associate me with crazies and loons when all i'm trying to say is that manufacturers are not trustworthy in this respect shows that you are not worth my time, so i'll end it here. thanks for the chat. if you do want to sometime in the future, discuss why people in the marketing industry are not honest, i'll oblige.
Science : Proprietary , Knowledge : Open Source
You make a good point -- some people are comparing apples to oranges when looking at an LCD TV vs. an LCD monitor. Personally, between my home and work computers, I am using four LCDs and no CRTs. Whee! It makes a huge difference in the way I feel at the end of the day. No headaches (unless it's simply from lack of sleep! :))
But the TV is a whole different story. I spend far less time in front of it, and in a proximity nowhere near how close I sit to my computer(s). CRT TVs are not hard on the eyes while CRT monitors are, and it's because they are used in very different ways.
You could Google for VESA instead of putting it in quotes as though it were some foreign term. But then again, why would you need to Google for VESA? Since you're an expert on the subject of computer video hardware, you would surely know about the standards body that has guided the industry for the last 15 years...
Marketing people may often lie, but that does not excuse consumers' ignorance.
There are 1.1... kinds of people.
Clearly there's some spin going on. I think I'll just wait a few more years on that purchase, just like I waited on that DVD burner when the standards were crazy and dual was a four letter word (as in dual layer).
I Browse at +4 Flamebait
Open Source Sysadmin
Now, these manufacturers are playing number games here. They don't measure how long it takes to show the requested pixel shade, but rather how long it takes to pass the requested pixel shade. If you look at the oscilloscope, the LCD hits 175 in 4ms, but continues to rise to 210 for several ms past that. It'd be more honest to at least measure how long it takes to peak. The ISO/VESA standard measurement for these values don't reflect the speed (or lack thereof) of the display, either. White-black-white transitions aren't a typical usage pattern by any stretch of the imagination. And unfortunately since faster response rate sells, manufacturers have a lot of motivation to find new ways to fudge the results to give them an edge in the marketplace. Unfortunately LCD performance can't be measured with a single number (or two or three or...)
Now, I own an NEC Multisync LCD1760NX which was rated as a 16ms panel when I bought it. How much faster is that VX924? How much compared to the VP191b? With all these number games, I honestly have no way of knowing. I can assume one thing, though, the VX924 certainly isn't 4x faster, and probably not 2x faster, either.
I used up all my sick days, so I'm calling in dead.
The fundamental reason for motion blur on LCD, which can not be solved using faster crystals, is the sample-and-hold property.
A video frame will remain on the screen for 1/50th (1/60th for NTSC, 1/24th for film material) of a second. Then, instantly, the frame is refreshed and all objects "jerk" towards their new positions. If you were tracking one of the objects with your eyes, your brain cannot cope with this instant movement, and instead tries to "see" the motion as smooth. For example, half-way during the showing time of the frame, the eye is already half-way shifted to the next expected object position. This results in a blurred perception of the object.
A CRT does not have this problem, since the frame is only flashed briefly, after which darkness returns. The brain can integrate these flashes to perceive fluid motion without blurred objects.
The backlight technology described in TFA mimics CRT pulse behaviour, to remove this fundamental blur. If you take care of reducing the visibility of flicker, which in practice means going to at least 75 Hz, this is an adequate solution.
You can't have your cake and eat it too: it is impossible to have both flicker-free display at limited frame rates and perfect motion portrayal.
Film is actually used because, historically, the electronic cameras and recorders sucked beyond belief. Resolution was crap. Media self-erased and wore quickly. Dynamic range was pitiful, and saturated highlights were sharply clipped and blown out. Noise was high. Occassionally you see electronic TV recordings from the '70s and the picture is butt ugly. Film may be expensive and cumbersome, but it has great resolution, great dynamic range, reasonably low noise, and lasts forever if stored properly. A true film-replacement electronic camera is still a laboratory curiosity and expensive as hell.
That's an important point. Migraine and eyestrain-induced-discomfort (which is probably mild migraine in many cases) depend on how and what you watch too. Computers use sharp, high-contrast content with repetitive patterns. The eye is constantly moving around in fast, jerky motions. There are incentives to constantly stare at the screen without breaks. This is very stimulating to the visual parts of the brain. (I'm typing this with the lights turned off, wearing sunglasses. Three guesses why.) Reducing flicker is one of the few ways to reduce the irritation.On the other hand, TV and movies have soft edges and low contrast, and the eye does not move much or rapidly. You can look away occassionally without feeling like you're missing something. So the designer can get away with a lot more flicker without pissing off viewers' brains.
the reason i put it in quotes is that i've never heard of vesa in the last 5-7 years in regards to video standards, especially in relation to lcd technology.
you may also want to read a few more articles about lcds... if you think the response rate listed on the box is actually accurate.
no need to get huffy, i'm just saying that they are deliberately misleading customers. they certainly got you representing lcds in a better light than they ought to be.
Science : Proprietary , Knowledge : Open Source
I always thought the problem was the crappy plasma tech. TFT should adress this problem but its probably not cheap enough thus the ugly hack they try to pull. I watch both movies and tv on my 17" LCD (TFT) and i cant say i have ever even noticed any ghosts in the picture. On cheap laptops with plasma screens on the other hand its all a crappy blur.
HTTP/1.1 400
"Philips will do something similiar to a Cathode Ray Tube (CRT) by switching the fluorescent backlight on and off at a rapid pace." ...thus eliminating the only real advantage of LCD over CRT.
Anagram("United States of America") == "Dine out, taste a Mac, fries"
I am actually wondering whether ghosting is still going to be an issue in the future. Already, I own a nice Samsung LE32R51B 32 inch LCD which has an 8 ms response time (!!) and no ghosting can be seen in any game whatsoever - this is commonly agreed on by owners of these tv's. I guess for bigger screen sizes it is still a problem, but nothing that can't be fixed I guess.
thank you for finally explaining this to me. i get exactly this in counterstrike on my hyundai Q17 and wondered what the hell it was.
to be fair, i have only noticed this on dust and dust2, the monitor is otherwise absolutely perfect for gaming. i play a lot of GTR and Battlefield2 and have never noticed any other problems. i would never have another CRT.
Please tell me where I can find a LCD 21" monitor for $500 or less.
Or give me the reference of one. Because I just can't find any decent one under $900.
I have a superb 21" CRT from Mitsubishi, and if I can find a LCD that can display native 1600x1200 at under $500, I'm sure to buy it (even if it does not support HDTV).
Unfortunately I never found any.
Now tell me, where is this gem ?
> The ghosting issue is such a holdover of 1999, and every half-wit, still trying
> to defend why they can't affort a new LCD display, imagines that they see
> ghosting all over the place on LCDs, while they carefully block out the same
> ghosting that occurs on all medium or long persistence phosphor CRTs (which is
> every high end CRT, humorously enough). Keep on convincing yourself, though.
I'm a programmer - I do a lot of dev work and game playing on my CRT, and whenever I've checked I've seen ghosting. Believe me I can afford to buy any LCD monitor I want. Perhaps you should get your eyes checked. You sound like one of those guys who deny the point of encoding MP3 files any higher than 160kbps because "I can't hear any difference, so there isn't any".
Clearly, they are doing this simply to spit those of us who use XMAME. We just got rid of refresh-rate mismatches by switching to LCDs, and now the LCDs are going to be getting a 60Hz refresh-rate...
DAMN YOU PHILIPS!!! WHY WON'T YOU JUST LET ME PLAY SHINOBI???
Slashdot gets worse every day... Pipedot: News for nerds, without the corporate slant
The ghosting issue is such a holdover of 1999, and every half-wit, still trying to defend why they can't affort a new LCD display,
You're being silly. The ghosting is there for all to see, but you'll probably never notice it unless you're a gamer. I see it even on top of the line displays, although the problem is much better than it was only a few years ago.
Are you claiming that Philips is creating a strobing LCD for no reason?
A witty
So when I watch Monsters Inc. on this new LCD TV, the monsters will all be smooth?
Philips found the answer... now all they need is a problem!
It's really sounding like something made to the marketing dept. One more little word to push when they're selling their products.
---- You know how some doctors have the Messiah complex - they need to save the world? You've got the "Rubik's" complex
"If the pixels can respond to any signal within 5 ms"
I took the liberty of adding the emphasis to the keyword there, because that's the whole problem with the current generation of LCDs.
Yes, the day a TFT can completely switch between any two colours in 5ms or less, will be the day we'll stop complaining about ghosting anyway. Heck, even 12ms will do just nicely, _if_ it can actually switch between any two colours in that time.
But the problem with current monitors is that the numbers claimed by the manufacturer are bullshit. They're the best case scenario, not the worst case scenario. The worst case scenario for a "5ms" monitor can be almost 30ms for a single transition. (See some of the measurements on Tom's Hardware, and boggle.) Or you have "16ms" monitors which actually switch slower than "20ms" ones. (Not a joke: again, see any review on Tom's or Anandtech, and boggle at how the 20ms panel is actually the faster one.) Or "25ms" panels showing 140ms worth of actual latency.
The industry has been pretty much left to define for itself wth it wants to measure and how, and what ideal scenario numbers it wants to publish. And unsurprisingly, it did pick the ones that the marketroids liked, not the ones who bear any relevance for the consumer. So you get stuff like numbers measured in perfect darkness, and only until it gets within (an ever increasing) x% of the desired colour, etc.
Most of the improvement between the 140ms displays of the late 90's and the "6ms" displays of today isn't the actual panel, it's in creative measuring and advertising. The real latency did go down, yes, but the claimed latency went down exponentially faster. Every time the actual latency halved, someone invented an even more creative way to claim half of that again in marketting materials.
And then you have outright bullshitters. E.g., manufacturers who shamelessly advertise lower response times than even the panel manufacturer claims. (Sony was for years such a case: they quoted either the time to rise or the time to fall, long after everyone else had been dragged kicking and screaming into quoting the sum. So your uber-expensive new "25ms" Sony would in fact have more latency than a "40ms" from Iiyama.)
_That's_ the problem with those latency numbers: so far they're bogus, and they're likely to stay bogus. When that 5ms monitor hits the shelves, it may be (and probably _will_ be) actually nowhere _near_ being able to display a clean 200 fps. You're lucky if you can get a clean 30fps worth of latency on the worst case scenarios, and for more "normal" 12-16ms monitors you might get 10-20 fps class ghosting.
A polar bear is a cartesian bear after a coordinate transform.
> The image is projected onto the inside of the glass tube, which is nearly
> 1cm thick.
> Your eyes are continually shifting focus between the front of the glass,
> and the back (where the image is).
No they're not. If your monitor is even vaguely clean then it's pretty much impossible to focus on the glass (try it yourself. It's 99% transparent after all). You shouldn't be able to see it unless there's a massive refection on it (eg a window right behind you) - in which case, adjust the position of your monitor so this doesn't happen.
If you're sitting the correct distance away (at least 16 inches) then the fact that the glass is 1cm thick is totally inconsequential. ie, if you DO focus on the glass front somehow, then the phospor layer is still almost perfectly focused anyway (after all, it's only about 2.5% further away than the bit you're focused on).
Your eye always wants to focus on the thing which is most visible and that's going to be the phosphor layer rather than the front of the glass (unless you have a very dark background or your monitor is turned off). This is one reason why word processors now display text as black on white rather than white on black as this has been proven more legible (on both paper and monitors as it happens). They give you eyestrain because most people have their monitors too close or set up badly (too much contrast/not enough contrast, brightness too high etc) or they have a poor quality CRT which has blurry pixels.
I do a lot of dev work and game playing on my CRT, and whenever I've checked I've seen ghosting
And there's ghosting on CRTs. You see you probably heard "there's ghosting on LCDs", so the first thing you do with any LCD is do some ghost tests, confirming that there is, indeed, some ghosting. Yet if you did the same test on a CRT, you would see exactly the same thing, in some cases worse. Because the phosphor on a CRT has to persist between scans, it is built to hold the image for a period of time, some times a substantial period of time.
Get a black background, and drag something luminous around in a circle - on a Windows desktop you could use the trash can. Voila - it's a magical ghost garbage bin trailing it. OMG, there's ghosting on CRTs! Throw em out!
Are you claiming that Philips is creating a strobing LCD for no reason?
As I've said in other posts, both CRTs and LCDs exhibit ghosting, some modern LCDs doing so less than some higher end CRTs. From the Philips perspective, they're a large company that has to have a marketing angle to sell their sets - if they can claim a theoretical, imperceptible advantage, they will. Just because monster cable exists doesn't mean that I'm spending $200 for a 3' monster DVI cable.
> You see you probably heard "there's ghosting on LCDs", so the first thing you
.2 or whatever of a second on CRTS for white to fade to black - I can't see ghosting when it's not such an extreme change. With (some) LCDs I can see ghosting of the entirety of what's moving, for longer than .2 of a second, regardless of the source/destination colour.
> do with any LCD is do some ghost tests, confirming that there is, indeed, some
> ghosting. Yet if you did the same test on a CRT, you would see exactly the same
> thing
I can see ghosting on LCD monitors, but I can't see it on CRTs. I don't care if it takes
> Get a black background, and drag something luminous around in a circle - on a
> Windows desktop you could use the trash can. Voila - it's a magical ghost
> garbage bin trailing it. OMG, there's ghosting on CRTs! Throw em out!
This doesn't answer my question. Nice straw man...
I moved from CRT as soon as LCD's came out because I'm migraine-sensitive to the refresh rates on CRTs. Even 100Hz.
Please god I hope they don't put the flicker back in.
This doesn't answer my question. Nice straw man...
What question is that? Whether LCDs have ghosting? Well they do, as do CRTs, and if you don't like that get a DLP projector.
Of course, to use your insult in another way, you're like the guy that paints around his CDs with orange marker and uses Monster cables for all his digital audio connects. Someone tells you that it's better, and you convince yourself that you couldn't have it any other way.
Below around 10mSec reponse time (which is what good TV panels achieve) the primary cause is the fact that TFT-LCD's are sample-and-hold display devices not stroboscopic (flash and then dark) like CRTs. You could achieve 1mSec response and still not deal with the issue.
There are two technological fixes. One is to flash the backlight (actually you only flash stripes in the backlight but that's another story) or you increase the frame-rate. Increasing the frame-rate costs big-time silicon since you need motion-compensation to calculate the intermediate frames decently. Hence the interest in flashing/scanning backlight solutions.
Personally I too am not convinced about flashing. However I know the Philips research in this area is relatively sophisticated (flashing more when ambient light is low and its less noticeable etc etc).
Andrew
> What question is that? Whether LCDs have ghosting? Well they do, as do CRTs,
> and if you don't like that get a DLP projector.
Yes, but I've not seen ghosting causing a problem on any CRT I've had to use in the last 10 years (that's a lot of CRTs). I've seen ghosting causing a problem on over 9 out of 10 of the LCDs I've seen in that period.
> Of course, to use your insult in another way, you're like the guy that paints
> around his CDs with orange marker and uses Monster cables for all his digital
> audio connects. Someone tells you that it's better, and you convince yourself
> that you couldn't have it any other way.
No, because, just as I'm comparing CRTs and LCDs and finding the latter wanting when it comes to watching DVDs or playing games, I'd look into whether or not colouring CDs (actually it's green that hifi nerds use) or using expensive cable made any difference to the sound. Something tells me it's better, but I've yet to hear it. My hifi system is good enough not to require hitech placebos and snake oil.
I believe that LCD TVs are taking over fast. If I go into any home electronics shop, the LCD:s cost the same as the CRT:s did last year, and the CRT:s are on sale.
the reason i put it in quotes is that i've never heard of vesa in the last 5-7 years in regards to video standards, especially in relation to lcd technology.
I'm curious: What part of VESA's work did you pay attention to in the last 5-7 years?
From their standards page, it appears that a large majority of VESA's work since the mid-'90s has been focused on video standards and compatibility. Perhaps you were engrossed with the work from TCTG?
you may also want to read a few more articles about lcds... if you think the response rate listed on the box is actually accurate.
You might become better informed in general if you read with more care, and didn't falsely attribute statements or positions to others. I stated no opinions about LCD technology.
they certainly got you representing lcds in a better light than they ought to be.
Again, I wrote nothing about LCDs. I fail to see where you are getting this misinformation about my post. Perhaps you have me confused with someone else?
In any case, please consider that products within particular classes of any particular display technology are not homogeneous with respect to quality or technical characteristics.
There are 1.1... kinds of people.
With more and more TV becoming MPEG compressed anyway, having frames independent of the data in the previous frame is far less likely. Picture elements and frame definition are all getting mushed together and flattened out in the name of bandwidth conservation. I've seen far more streaking and artifacting as a result of overcompression than as a result of display issues. If anything, better displays make signal deficiencies more obvious. The best refresh rate, black level, etc. don't make a damn bit of diffrerence if the video is too highly compressed.
Try the Dell 2001FP (I know, 20", but comparable to the viewable area on the CRT). It is normally $749, but can be had for aproximatly $500 on promotions quite often. It displays 1600x1200 native.
One that is popular at my office is the Dell 2005FPW, a 20" wide screen. It displays 1680x1050.
My own experiments show that double-flashing 60 FPS video up to 120 FPS on a CRT (running the refresh rate at 120 Hz but updating scrolls at 60 Hz) produced a pronounced motion blur. But I have never tried to show a scrolling voice print with a movie projector either.
I don't know about $500, but you can get a ViewSonic VP201b for around $600 shipped on PriceWatch. That'll do 1600x1200 analog or DVI, and viewsonic handles analog input better than a lot of LCDs I've seen.
Actually, the glass on a monitor is not 1cm thick; its only 5mm or less.
I know this because I use a monitor faceplate as a serving dish (and no, it was never attached to a monitor, it came off an assembly line before being attached to the tube back and being coated with phosphor or aquadag, so its never been in contact with anything more toxic than anchovies).
Blank until
Horrible writing to say the least - or - a terrible mis-understanding of how a CRT works. First off, CRT's don't have backlights as the statement seems to imply, and secondly, CRT's don't eliminate ghosting by turning anything on or off. It happens that the decay rate of the phosphor is such that when the electron beam re-scans the tube, the phosphor has exhausted its charge from the previous scan.
To get a 'similar' fix, they would have to flip the pixels faster - not interrupt the backlight, which is a completly different approach to fixing the problem than doing anything 'like' a CRT.
Another problem of the CRT are the analog pixels, which are not perfectly sharp. They are smeared [...]
Oh? Looking close just now, I see that there are no "pixels" to speak of, there's hexagon patterned dots.
As for the "age" problem, what I notice is less detail shadows (although I've had screens which didn't show 50/255 pixels in the beginning - maybe they were used...), and for "coatings" I remember an old screen giving a green tint (mostly noticeable with grey images).
the sun is god
Could we get a poll on slashdot of fav matrix technology?
LCD / DLP / CRT / PLASMA / ??? / ???? / ?????
What about those of us who play FPS with hand puppets and rubber-band guns? Laugh if you like, but I've never had frame rate issues...
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> Get a black background, and drag something luminous around in a circle - on a
> Windows desktop you could use the trash can. Voila - it's a magical ghost
> garbage bin trailing it. OMG, there's ghosting on CRTs! Throw em out!
That sir, are your eyes. (More correctly: your brain's (needed) motion prediction because of the lag in transfering the image from the eyes to the brain)
"Omg I'm moving my mouse cursor around on a bright background and it's like 10 of them! Ghosting! Omg!"
(I'm 45.23956238756% sure I'm wrong)
the sun is god
I don't know of anyone who has an LCD as their TV apart from this one nursing home which got one last year.
Prepare to know a lot of people. The electronic stores are filling up with very competent 27"+ HDTV LCD TVs in the sub $800 range, and given that they're stocking so many obviously they are selling.
There is no HDTV deadline; it's digital tv in standard definition there's a deadline for...
Easy, reload the Dell site every day until you hit a day with a sale and a coupon. I just bought a 21" monitor there and the total after shipping came to $529, but it was $489 before shipping.
They've got a 20.1" one there right now for $561.75, and two minutes on google will net you a $75 off coupon. They had a 19" version for $287 the other day... It's hard to find a good 19" CRT for much less that isn't a refurb.
BTW, that 20.1" monitor has a biger viewable size than your 21" CRT. Even the 19" version is bigger than the viewable on many 21" CRTs.
The Frugal Gamer website does a decent job of keeping tabs on the Dell sales and coupon codes.
Focusing on closer distances (eye stretching taller)is a bit harder on the eye than farther distances (eye stretching flatter). The doc has a simulated computer screen that he set up and had me watch that while he watched what my eye was doing. Here is what happens. Since focusing close is difficult, the eye can't hold it and starts to relax a little and your focus drifts farther away. Your eye notices that you're a little out of focus and pulls it back in before you are consciously aware of it--wash, rinse, repeat, ad infinitum. My doc said that at the rate my eye was doing this shift/correct cycle, it would probably be going through this several thousand times a day during my 8 hours of work. He said, imagine you were repeatedly moving any muscle that much; of course it would get sore.
So, the computer glasses are to change the normal distance of focus to the distance I normally sit from my monitor. Effectively, they refocus things a little so that my eyes can sit at an ideally "no effort", relaxed position to look at my monitor. That has greatly reduced my eye strain headaches.
We may experience some slight turbulence and then...explode. -Capt. Mal Reynolds
Sure, you can model almost anything with almost anything else, as long as you've got the right math. But efficiency goes down the tubes.
For instance, I can make a shitty speaker in a bad room sound (mostly) like an awesome speaker in a good room using something like BruteFIR.
But, I lose system efficiency. To compensate for all the variables and deficiencies, one generally has to expend more amplifier power. Usually, it's a -lot- more. Often, it's more than is available or can be dissipated by the speaker. And nevermind the increased physical stress on the loudspeaker components themselves.
One runs out of dynamic range pretty quickly in this game.
So, you can do the same thing with an LCD, say, and remove ghosting as it happens. But, you will end up with a system with reduced contrast, and added time delay. (You have to correct for the ghost image -before- it actually happens. And if it's a black ghost on a white background, you'll need to correct it with a moment of something brighter-than-white. Which is impossible, unless you redefine white to be something closer to what would normally be grey, and are happy with the overall reduction in brightness in exchange for a lack of motion blur.)
Kid-proof tablet..
I wanted desperately to love the LCD monitors. They are not as hot, they don't take up as much desk space, less danger of radiation and they have very sharp pictures. I do a lot of audio and video editing and computer graphics, and I do get into a game of Soldier of Fortune or Halo with my kids now and again - so I bought a 19" Dell that promised it was very fast on the refresh so it would be great for games. I tried it for a couple of days, but I had to return it because it made me carsick all the time because of the "ghosting/motion blurr" stuff. Before returning it, I went on a quest to every store with these on display and every one that belonged to someone I knew and found that all I needed to do was a few simple tests like moving the mouse cursor across the screen to see that they ALL had streaky blurrs following every dark thing that moved. The higher the picture quality was the blacker the blacks seemed to be and the blacker the blacks got the more exaggerated the blurring was. The higher the picture quality settings in the games were, the worse the blurring looked as well. I also noticed that on a screen any bigger than 15" the screen always appeared to be lit unevenly, depending on the angle it was set at, where I was seated and whether I was slouching or sitting up straight. Some were much better than otheres, but they all did it to some degree. I always had to move my head around to see how something full screen looked. I bought a 21" Philips CRT monitor for less money and am much happier with it. I have been looking at computer monitors up to 20 hours a day since 1989, and I solved the flicker/eye strain problems of CRTs years ago by just getting a monitor that supports 100+ refresh rates. Another HUGE problem with LCD monitors is that they only have one resolution available where the resolution is sharp and clear. I never saw any warnings about this very serious problem anywhere "before the purchase" although I found quite a few people who became aware of it after they bought their LCD panels. If you set them to any resolution except their "native resolution" the picture is extremely grainy and fuzzy, and the colors are way off. I don't like having to use only one resolution and only the one they decide I should have. My son's laptop computer has a native resolution of 1600 on a 15" monitor which is really too small for a normal person. If he sets it to anything else the picture quality is really bad. I think the flat panel monitors are all right for doing static work and ok for that up to 17." I use one at work like this and although I am always having to adjust the angle depending on if I am standing or sitting to see the picture well, It suits my needs well because it fits on a counter top where a regular monitor would not. I really think it is good that people have choices and can use whatever best fits their needs. I expect to be using only flat panel monitors eventually when the technology improves. I say let them try anything they want. There is no danger that a bad technology will take over because nobody will buy them if they are that awful. The manufacturers will make what people are willing to buy, so let them experiment. Maybe they will eventually come up with something we can all use.
I tried it for a couple of days, but I had to return it because it made me carsick all the time because of the "ghosting/motion blurr" stuff. Before returning it, I went on a quest to every store with these on display and every one that belonged to someone I knew and found that all I needed to do was a few simple tests like moving the mouse cursor across the screen to see that they ALL had streaky blurrs following every dark thing that moved. The higher the picture quality was the blacker the blacks seemed to be and the blacker the blacks got the more exaggerated the blurring was. The higher the picture quality settings in the games were, the worse the blurring looked as well.
I also noticed that on a screen any bigger than 15" the screen always appeared to be lit unevenly, depending on the angle it was set at, where I was seated and whether I was slouching or sitting up straight. Some were much better than otheres, but they all did it to some degree. I always had to move my head around to see how something full screen looked.
I bought a 21" Philips CRT monitor for less money and am much happier with it. I have been looking at computer monitors up to 20 hours a day since 1989, and I solved the flicker/eye strain problems of CRTs years ago by just getting a monitor that supports 100+ refresh rates.
Another HUGE problem with LCD monitors is that they only have one resolution available where the resolution is sharp and clear. I never saw any warnings about this very serious problem anywhere "before the purchase" although I found quite a few people who became aware of it after they bought their LCD panels. If you set them to any resolution except their "native resolution" the picture is extremely grainy and fuzzy, and the colors are way off.
I don't like having to use only one resolution and only the one they decide I should have. My son's laptop computer has a native resolution of 1600 on a 15" monitor which is really too small for a normal person. If he sets it to anything else the picture quality is really bad.
I think the flat panel monitors are all right for doing static work and ok for that up to 17." I have one with an auxilliary computer at work and although I am always having to adjust the angle depending on if I am standing or sitting to see the picture well, It suits my needs well because it fits on a counter top where a regular monitor would not. I really think it is good that people have choices and can use whatever best fits their needs.
I expect to be using only flat panel monitors eventually when the technology improves. I say let them try anything they want. There is no danger that a bad technology will take over because nobody will buy them if they are that awful. The manufacturers will make what people are willing to buy, so let them experiment. Maybe they will eventually come up with something we can all use. But I am not expecting to see anything suitable for high resolution with quick motion for another 3 years.
Experiment 1 was flickery but no motion blur, experiment 3 was no flicker, no motion blur, experiment 2 was no flicker but definite motion blur.
That is the whole point of TFA. People had been focused on boosting the response time of LCD pixels but that helped motion blur a little but didn't solve the underlying problem. Getting blur-free motion from display of a sequence of still frames requires strobing the frames. Based on Philips saying that a 30 percent strobe interval didn't fully remove the motion blur, I am guessing a non-strobed display would need to run upwards of 300 FPS with 3 ms pixel response time to get a non-blur motion with a non-strobed LCD display.
People are treating me like a fringe-science nut case for coming up with independent confirmation for a vision psychology finding coming out of a major industrial lab. Go figure.
The future of LCD backlighting is in LED technology, not flourescent lamps. No matter how bright or how rapidly strobed a FL backlight is, it is still poor-quality white light. Flourescent tubes only produce an approximation of white, not true white light. Since an LCD is basically a varible light filter, the colors that come out the front are only as good as the spectrum of light coming in the rear.
By using Red, Green, and Blue LEDs in a backlight (as Sony and Samsung among others are developing) the LCD has a true (RGB mixed) white light that enables an LCD to deliver 110% of the color gamut of the original NTSC color spec!
In addition, LED response times are such that they can also be strobed for the same effect.
Yet another advantage of LEDs is that they have a lifetime significantly longer than FL tubes so the LCD would have an operating lifetime close to that of a CRT. In addition, since the color balance of the white balance can be adjusted (being made up of RGB light) the color balance of the screen can be maintained accurately over the 10-year (minimum) life expectancy of the backlight.
Read a preview of my novel CYBERCHILD at www.smartalix.com/cyberchild
"It's called migraine. For whatever reason the neurons in some people's brain are way overexcitable. Zapping them with a repetitive stimulus causes them to go nuts and spew inflammatory chemicals. This inflames the membranes surrounding the brain. It is basically non-infectious "benign" meningitis; you don't have a virus eating your brain, it just feels like it. Depending on how vigorous the problem is, the pain ranges from mild discomfort to suicide headache."
Actually, while migraine is another (more common issue), it wasn't what I was thinking of. I was talking about epilepsy.
Prior to going on medication, my friend was at high risk of seizures just from being near fluorescent lights. CRT monitors would make him very sick.
Now that he's on medication, he's been seizure-free for a few years. He still can't go anywhere where the lighting is predominantly fluorescent for more than 10-15 minutes (and as a result is now on disability because of his medical conditions), and has to be VERY careful about what monitors he buys because flicker can make him VERY sick.
retrorocket.o not found, launch anyway?
Lights making your friend sick sounds remarkably like migraine. When he is sick, do sounds also seem really loud to him even though they're normal volume? What about cold hands or other strange symptoms? For years I rarely had headaches from my migraine problem, just abdominal cramping, extreme nausea, faintness, and a general feeling of illness, as well as sensitivity to light and sound. I kept telling doctors that I started feeling worse as soon as my eyes opened in the morning; they decided I was mentally ill. Sometimes I didn't know if I would make it out of the grocery store conscious, which I now know was from the cheap yet bright lights they use. Eventually I developed the visual aura and headaches and finally started getting relief from anti-migraine drugs. (Still haven't found a good treatment though.) Given your friend's debility and the fact he has a high risk of migraine, it would be worthwhile to try migraine drugs and see what happens. Many of the migraine drugs are cheap and safe, and play well with anticonvulsants, so this shouldn't be a major undertaking. He also might want to try different anticonvulsants; Topamax actually made my migraine problem worse.