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Monitor Basics - LCD vs. CRT
Herbal V wrote in with a little article discussing the differences between LCD and CRT. Briefly summarizes all the major issues (Price, Refresh Rate etc). More of a beginner level piece, but as LCD prices are dropping like rocks, it's good to be aware.
Nothing for you to see here. Please move along.
Typical, a story about monitors comes along, and mine decides to censor it.
liqbase
Monitors - LCD vs. CRT
As the technology has improved and the prices have come down, LCD (Liquid Crystal Display) monitors have rapidly been replacing CRT (Cathode Ray Tube) monitors on desktops around the world. ComputerWorld first reported that LCD sales would surpass CRT sales for the first time in 2003, a lead that it didn't hold for good. But according to DisplaySearch, a flat panel display market research and consulting company, the sales of LCD monitors regained the lead over CRT sales in the third quarter of 2004,a lead that it should eventually hold for good.
The question is why choose LCD over CRT? There are several pros and cons to consider, and a few items will be considered in this Tech Tip, such as: Price, Size, Image Quality, Energy Consumption, Personal Comfort, and Response Time.
Price
The price of LCD monitors is much lower than a few years (or even months) ago, but still far exceeds the price of a comparable CRT monitor. For example, I spent about $600 (US) on a Viewsonic VA-720 17" LCD monitor in early 2003, and see that the same model now sells for less than $300. A significant price drop, but in comparison a 17" Viewsonic CRT monitor can currently be purchased for less than $100. The ratio of prices may have narrowed from about 5:1 to 3:1, but the aging technology behind CRTs still allows it to hold the lead.
You can't even compare prices of CRTs to LCDs in ComputerGeeks.com's monitor section as they are right in step with the sales information provided above, and now only carry LCD monitors. Prices vary, even among LCD monitors of the same screen size, so there has to be something more to it than price.
Size
One reason that LCDs have gained in popularity is because of their small foot print. The overall size and weight of CRT monitors far exceeds that of LCD monitors. CRTs share the same image processing technology with tube televisions, and therefore share the same bulky style of housing. For example, the manufacturer's web page lists this ACER 19" LCD monitor as having a depth of a mere 6.9" (including the base) and a weight of 12.1 pounds. As a point of reference, a 19" ACER CRT is significantly larger with a depth of 16.86" and a hefty weight of 46.31 pounds.
Desktop real estate is precious, and an LCD will require only a small fraction of the depth that a CRT would require. And if there isn't even enough room on your desk for a slim LCD monitor, the low weight makes them perfectly adaptable to be hung on the wall, or off of a radial arm mount, such as this one from Office Innovations.
Image Quality
Image quality is generally considered to be better on an LCD, as each pixel is generated by a specific set of transistors in the screen, which produces a crisp image. But some features that fall under the general heading of image quality might not favor an LCD, including viewing angle, brightness, and contrast.
Early LCD monitors had a fairly narrow viewing angle that made clearly seeing the screen from anywhere but directly in front of it difficult. This has improved greatly, but still doesn't quite rival the viewing angle of CRTs which provide the same picture quality regardless of the angle. A monitor with a maximum vertical viewing angle of 120 degrees should not be hard to find at this point, with many monitors now being able to provide an even greater angle.
Brightness is an area that LCD monitors may have the edge over CRTs, but it varies widely from unit to unit. The standard measure for brightness is referred to as "nits", which have units of cd/m2 (candelas per square meter), where a higher number is better. Looking at three of the 17" LCD monitors currently available from ComputerGeeks.com as examples shows two with brightness specifications of 400 cd/m2 and one with a brightness specification of 250 cd/m2. As a comparison, the typical CRT monitor may provide half the brightness of an LCD, as confirmed at Viewsonic's Monitor University.
Contrast is similar to brightness in the fact that
And now, what was described as a quick and useful overview of LCD vs. CRT displays, has become neither.
Anybody else see the irony in this?
Read: Rabbit Rue - Free serial nove
Thing even came with a wall mount, too bad I live in an apartment (though toothpaste does have its other uses...)
Size is great, too, because a 17" LCD is almost as big as a 19" CRT :-)
A feeling of having made the same mistake before: Deja Foobar
but as LCD prices are dropping like rocks
Worst analogy. Ever.
Free XBox, PS2
Well, LCDs are clearly on the way out. I just hope all those CRTs will be recycled (including TVs) and not end up in our water supply etc. How do my fellow Slashdotters recycle their old CRTs?
I want to tell you about the differences between direct current and alternating current and why direct current should be used as the standerd for the United States Power grid.....
Sincerly,
Thomas Edison
Everyone has been talking about LCD price drops for the past 2 years but it just has not happened. I've been in the market to buy an LCD monitor for the past 2 years and I have not seen any significant drop.
With all the news of companies dropping plasma, more LCD plants being opened, production being increased, technology improving, why hasn't the price of LCD monitors been cut in half?
I think it's because it has the cool factor that lets the companies sell it at whatever price they want.
Look at the quality of LCDs in some laptop and how cheap they are. OFten times a comparable LCD for a Pc would be more expensive than he laptop WITH the lcd.
The article only briefly mentions response time -- doesn't explain it. Response time was the reason I returned the LCD I bought and went back to my CRT -- DVD playback was awful. I imagine there are people who don't notice it, just as there are people who are more sensitive to lower CRT refresh rates, but it was hellish for me.
stripShow - Where WordPress meets webcomics
It's funny, the main reason why I dumped 3 of my 20" Sun monitors for an Apple Cinema Display was the health issues. Sure, we have herd all the stories about special cameras that can read the material on your CRT through walls (and the person sitting in front of it), but that didn't stop me. No, I went ahead and set myself up with enough radiation to cook lunch. 5 months later, I found myself having trouble shaking off common colds, and my appetite went down hill. People should be aware of the health issues, not just specs.
Un ortun tely, my LCD sc een su fer fr m a h rible case of de d pixels. So tim s it is very dif cult to re ly to the any gre t ar icles on Sla dot and other f ne for ms. Oh wel , I will gladl pay the price j st so hat I may ska e on the e ge of the raz and la gh at t se moron with their big du b box . Ha Ha Ha !
I just recently purchased my first Mac. Scary I know but I promise not to become a Slashmacbot... Anyway, in line with the purchase I figured why not move to an LCD setup as well? This article explains several of my reasons for doing so but leaves one out...
Energy Consumption
LCD monitors definitely hold the edge over CRT monitors when it comes to being energy efficient. The huge tube in a CRT monitor is the source of most of its energy consumption, and a comparably sized LCD may use just a fraction of the electricity. Taking a look at this 19" Jetway LCD monitor shows that it consumes 48 Watts during normal operation, which is less than your typical light bulb. In contrast, a 19" CRT such as this one from Viewsonic may draw up to 160 Watts. Therefore the fraction of electricity used in this case is 3/10, and could translate to noticeable savings on your electric bill.
I currently have two 17" CRT monitors on my L-shaped desk. One is a newer model "flat screen" and the other was a freebie HP branded CRT. I know that they are sucking power and sending that power back out as radiation directly into the side and front of my face (as they are surrounding two of the three sides of my head). I have switched to a lot of energy saving bulbs in my house and I plan to switch more as the bulbs die off. I have switched to a programmable thermostat (that isn't 5 degrees off like the one that the original owners had) to save electricity/gas during the day and evenings. Why not my computer crap too?
I have even gone so far as to make sure that if I am not going to be home for more than 24 hours my non-essential computer equipment is off. A few bucks here and there equals beer later.
Personal Health and Comfort
The main benefit that LCDs have when it comes to comfort is the reduced strain on your eyes. The reduced glare on the screen's surface, and the elimination of a typical CRT's "refresh", can prevent your eyes from getting tired from extended use. A CRT monitor redraws the image on the entire screen as it refreshes, whereas an LCD monitor only changes the necessary pixels during a refresh.
There may also be the unquantifiable effect of reduced electromagnetic emissions on LCD monitors. The exact impact of electromagnetic emissions may not be fully understood, but in general less is considered to better, as addressed in this article. And, your back may also appreciate an LCD when it comes time to move, as the example above shows a 19" LCD monitor weighs about ¼ as much as its CRT counterpart.
What I have noticed is that using both at work (and now both at home) that I have significantly MORE eyestrain. Moving back and forth between the two seems more harmful than just sticking with one or the other. Sadly I am going to be in this situation at home for a while yet but at work I have only this 20" CRT to replace. The 23" LCD is in IT and waiting for install so it won't be too long. I was QUITE surprised when I went to pick up the 17" LCD at the FedEx hub that it fit easily in my trunk and was light enough for me to hold with one arm safely. I can't say that much about lugging my 17" CRTs around. Woo for that.
My other reason for loving LCDs is desk real estate. With my CRTs tons of desk space is lost to their screen, their rear ends, and their bases. With the new LCDs I have quite a bit more room to stack cans, plates, etc. It also makes me feel more "free" to move around in the tight space that my computer area is located.
I look forward to my second LCD at home and the savings in health, energy, and space it will give me.
I know the answer to your question but I refuse to answer you because you're an iPod whore.
I hate you.
Kind of OT, but important - if you are running XP with an LCD screen, don't forget to turn on ClearType. ClearType dramatically improves the quality of text displayed on screen, to the point where my work laptop almost looks as good as my OS X box w/CRT at home.
ClearType takes advantage of the fact that LCDs make coloured pixels out of three adjacent sub-pixels (usually R-G-B), rather than a CRT which focuses all three of its guns on the same spot. By varying the intensity of the three colours in each pixel, ClearType effectively triples the horizontal resolution of type. The trade-off is some slight colour-banding in small fonts, but the payoff is a much more readable screen.
I stumbled across the settings by accident. With the increasing popularity of LCDs, I'm surprised that Microsoft doesn't promote it more.
When you have nothing left to burn you must set yourself on fire
Do you have a big desk?
Buy a CRT.
Spend the rest on booze and hookers.
Do you have limited space and/or need to move around.
Buy a LCD.
Pay for booze and hookers with a credit card.
Beep beep.
It depends...if you're using the VGA input, the card is still outputting an analog signal with refresh. It's handled within the monitor with an analog to digital converter. So as long as you don't specify frequencies or refresh rates that the converter can't handle, there's no problem. I usually just set mine to 75 Hz. If you're using DVI, then none of that applies...but monitors that support DVI are still too expensive.
Try this article for a good overview of the different types of LCD panels (TN, MVA, PVA & IPS):
X-bit's Guide: Contemporary LCD Monitor Parameters and Characteristics
It weighs in at 27 pages, but if you really want to know what you're talking about when discussing LCDs, it's required reading.
Site & blog: http://www.mayaposch.com
Here's some of my experiences buying an LCD monitor. If you're not picky, it's easy to buy one; if you're picky, well, it's not so easy.
Reasons I haven't switched to using LCD displays:
* Price: A 19" High Quality CRT w/ 18" viewable area, is hundreds of dollars cheaper than a high quality 17" LCD (with the ultra low response time, excellent colour, etc.)
* Sucky low resolution support: I maintain a Linux port of an adventure game system that runs at resolutions including: 320x200, 320x240, 640x400, 640x480, 800x600. Every LCD i've ever seen has one of two sucky ways of dealing with low resolutions: Stretch the image to fit, blurring the heck out of it, or displaying it at near postage stamp size.
Show me an LCD that solves both problems and I'll run to buy it in the very near future.
my wife's more popular than me.
just kidding...!wife.
An Indian-American Hindu committed to non-violent thought/speech/action alarmed by the global explosion of radical Islam
The article barely touches on the response time inadequecies of LCDs. It even goes so far as saying that LCDs have a better picture than CRTs, when anyone who uses their computer for visual design knows the color problems with LCDs.
Come on here, just because you get a nice radiation bath with CRTs is no reason to hate on them and deny the areas that they excel over LCDs: color, darks/lights, any moving picture, etc...And this will be borne out by the legions of gamers, graphic designers and cg programmers who use CRTs because they are superior in these areas. I estimate I'll be able to buy a LCD in about 10 years that won't have these problems. Till then, it's always CRT for visually intensive work, maybe LCD for web surfing and office apps.
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(^.^) INFECTED
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Most monitors I've seen specifically request ONLY 60Hz for their analog connections. If you set it at anything higher, you will get some sort of "Out of range" message on all but the best (Viewsonic will allow higher refresh rates on a temporary basis, but constantly nag you to lower your rate to 60Hz).
Homer no function beer well without.
I love LCDs myself and have replaced all of my monitors with LCD displays, but even to me this 'comparison' reads more like a fanboy article than an objective comparison.
CRTs certainly win out when it comes to contrast, yet the article only begrudgingly says that CRTs "may still have the edge". "May"? They absolutely do rule for contrast. When the electron gun turns off on a CRT the screen is black. On an LCD it's dark gray.
I believe CRTs also win for refresh/framerate. The 'reviewer' relies on manufacturer specs to evaluate transition times. Are these the same manufacturers who used to tell us that their 15" monitors were 17"? Or the same ones who would use inappropriate contrast tests in order to claim huge ratios? It's true that LCDs don't flicker, but a fast refresh CRT doesn't flicker either and the CRT can switch images very quickly. The best LCDs that I've seen are still inferior in this regard. I'd prefer to see independent testing to validate these claims of 16ms switching times.
Again, I love my LCDs and wouldn't trade them even though Doom III does smear a bit when I pan around. I love the low power consumption and I love the ease on my eyes, but it still doesn't change the fact that this article is just some fanboy fluff piece.
The price isn't dropping, that I can detect.
More importantly, the higher resolution monitors are still not available. As I type this on my 1920x1440 screen, I wonder why I would be motivated to pay a high premium for no more than 1280x1024 resolution. I do have one LCD panel that I like, it's only 1024x768, but it's mounted on my keyboard rack, and serves a specific purpose where low resolution is not a problem.
But everywhere else, virtual desktop real estate is much more important than physical desktop space, particularly with regard to the volume of the monitor. If anything, a flat panel is a net loss, because I lose the shelf that the display provides.
The other thing that stops me from buying an LCD is the ridiculous policy that "10 or less missing pixels" is not a problem. It would be a serious problem for me, to have missing pixels anywhere except *maybe* within a pixel or two of the edge.
Just maybe. I'd still be upset. But anywhere else, and I'd be sick about it.
Because of that, I don't buy an LCD panel. Maybe if I were to buy one from a brick/mortar store where I could test it before buying.
For what these things cost, I think I should be able to ask the merchant to test it, and know before sending the damned thing that it has 8 missing pixels.
I have a big problem with that policy. It tells me the manufacturer doesn't understand the process well enough to have sufficient quality control.
-fb Everything not expressly forbidden is now mandatory.
Actually, these beginner guides and technology simplified articles are handy for us geeks to have.
Presenting facts and information to the layman can be a difficult task, and its good for us to see how its done.
Instead of us all saying something like "let me try try to explain it" to a family member or friend, you can direct them to an article written with them in mind, and with enough information to answer most of their queries.
liqbase
How do my fellow Slashdotters recycle their old CRTs?
Out the window, then drop a mallet on it (literally, out the same window), repeatedly, until the screen with the metal frame around it is the only part remaining, and the rest is pulverized. The screen will be the only part remaining, because it's a half-inch thick glass, as opposed to the wimpy glass in the back part of the tube, and the cheap plastic that the rest of the thing is made out of. Then take the screen, line it with a doormat, and ride it off snowy hill. Glass has a really small friction coefficient against snow.
Don't try this at home:-)
Don't give up, give a quality LCD a try first and you may never go back.
Response time is a critical feature for me. I won't buy any LCD screen unless it's in the 16ms-or-better range for typical pixel response.
My NEC LCD1760NX is great for games and movies. No hint of ghosting at all. Solid, bright, good footprint too. Digital/Analog connections as well.
LCDs still have problems with color correction for serious graphics work, or so I'm told. But you couldn't pay me to get in front of a CRT anymore. My eyes won't take it.
Is it true that DVI is limited to 60hz, and so that even if LCD refresh times improve, DVI always will be limited?
LCD refresh rates won't "improve", so you can stop worrying about that.
The reason that they won't improve is that 60Hz refresh is plenty enough for an LCD monitor, even with fast motion video on it. The CRTs need a faster refresh rate because they flicker, i.e. each pixel's brightness gradually falls off from refresh to refresh. LCDs don't flicker, i.e. a pixel stays at the same exact brightness the whole time between refreshes, so the refresh rate is limited by the desired frame rate, not flicker, and you really don't need faster frame rate than 60Hz.
The article overlooks one of the biggest reasons to not buy an LCD monitor: The bad pixel problem.
Whether it shows up as a dark/missing pixel on brighter images, or a bright pixel on dark images, this persistent problem is an ugly side of LCD monitors.
Ever since buying an iMac with a single bright blue pixel on its LCD, I've resolved to never again buy another LCD that isn't warranted to be 100% defect-free. At least for now, no manufacturer except for Samsung (and only in S. Korea) seems to believe that more than zero bad pixels constitutes a problem.
The general line still is that a bad pixel or two is "normal". Well, it is as normal as an LP album with a scratch, a CD with an intermittent skip, or a dropped cell phone call. It happens, and much of the buying public accepts it, but it sucks and such garbage has no place in a quality product.
Vote with your pocketbook. I do. Caveat LCD emptor!
The author is also a bit wrong in writing that the brighter the monitor, the better. Actually, some LCD monitors can be just too bright. You have to remember that LCD works by blocking light generated by lamps, so if the lamps are too bright, you won't block enough light to make black appear really black (it is especially visible in darkened room). Another caveat is that LCDs perform worse at representing a whole spectrum of colors (they're worse at representing warm colors). And that modern LCDs often do not show full 16.4 million RGB spectrum, only a subset of it and interpolate inbetween, which makes gradients worse.
Having said that, I wouldn't give back my 17" LCD for any CRT, my eyes are too precious for me.
I bought a model that was reviewed on newegg.com by umpteen people and many said they had no dead pixels.
I tend to ignore such reviews. First of all, I have no guarantee that shop owners do not edit/cut out bad reviews. Second, a sizeable chunk of the reviews is written like "Hey, I just bought it 4 hours ago and it looks GREAT!!!! No more headaches and the fonts look so sharp!! Whopeee!". Sorry, this is not my idea of a noteworthy review.
"Long run is a misleading guide to current affairs. In the long run we are all dead." (John Maynard Keynes)