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LCD Display Questions - Longevity and Monochrome?
Jack Frost IV asks: "Since higher resolution LCD panels have started to become a lot more common, many people have been complaining about dead pixels. I just received two SGI flat panels direct from the factory, and each shipped with a single dead pixel. In fact, the second display was a replacement for the first (for an issue unrelated to the dead pixel). While I understand the difficulties in manufacturing the displays, the single dead pixel doesn't concern me right now, as I don't notice it often. What bothers me is how many more pixels these displays will lose during a lifetime; say over the next three to five years. I want to replace a lot of my CRTs (Yes, *some* of us don't do color critical work, and LCDs are perfectly OK) with LCD panels, but if, say, a dozen pixels are going to die in 3 - 5 years, it's going to be quite annoying. SGI claims that once the pixel burns out, you'll never notice it was gone... but I don't buy it. Can anyone explain some of the longevity and degredation issues relating to flat panels?"
O'Bunny queries: "How come nobody apparently sells monochrome LCD monitors for PC-like devices? I'd love to have a largish (say, 1600x1200) flat monitor that: doesn't weigh five thousand pounds; isn't fifteen feet thick; and doesn't cost an arm and a leg.
The rationales that I've heard behind the high costs of these monitors were:
- The manufacturing yield is low because of the large number of transistors that need to all work properly to display colours.
- The economy of scale currently is aimed at laptop users, for whom a 1600x1200 screen is impractically large (unless you happen to be Andre the Giant)
Ignoring the second part, why doesn't anyone make a decentmonochrome LCD monitor for those of us who want a large screen but don't necessarily need color?
In my case, I want to edit multi-channel audio. A Color display adds almost nothing to the information that I extract from the screen. I can select, cut, copy paste, apply effects, and otherwise mangle the sounds as well on a 1-bit per pixel display as I can on a 32-bpp monster.
I am also a technical writer. The documents I write are produced on a B&W laser printer, mostly. Certainly, on-line documents (and even most printed ones) can benefit from intelligent use of colour for various reasons, but most printed documents end up in black and white (mostly for cost reasons). Again, colour adds little to the experience.
So, I guess my question really comes down to the following:
- Where can I get a large monochrome flat-panel monitor for a PC?
- If I can't get one for $less than a colour flat panel, why not?"
This is because the receptionist needs only one monitor, while even a small operations center needs, at a minimum, about 40.
Even with 17" LCDs going for four or five times the price of CRTs, it saves money in the long run due solely to the fact that the operations consoles can be shortened by about two feet each.
This might not hold true if you're building a facility in the middle of nowhere, or if all those LCDs wind up having a maximum life of about five years; but where real estate is even moderately expensive, the rental on the floor space CRTs would take up would make their total cost of ownership higher than that of LCDs in about five years.
I expect that the break-even point would come even sooner if one was inclined to figure in the cost differential of powering and cooling the things. CRTs use a lot more power and generate a lot more heat than LCDs. I used to use the back of a Sun 20" monitor to keep my breakfast bagel warm in the mornings until I was ready to eat it. The vents there were so well suited to this task that I think they must have been designed for this purpose.
Of course, the potential problem with this reasoning is that CRTs last almost forever, while all these LCDs might well sputter and die within that five-year period.
I've heard that the limit to an LCD display's life is usually its backlighting; supposedly the backlighting dims gradually over time, making the display harder to read. This is why LCD display manuals recommend you turn the display off or put it to sleep when it's not in use, even though it won't suffer burn-in problems like a CRT. I haven't ever seen an LCD display with backlight problems, however (though most LCD displays seem to take a few minutes after power-on until they reach their normal brightness).
As for dead pixels: Sometimes you can 'un-stick' them by massaging the screen over a dead pixel very gently.
The only problem I've had with my Apple Cinema Display is some mild 'burn-in,' believe it or not. Apparently with any LCD display, if you leave a static image on the screen for a while, the LCD hardware will 'remember' that image and you'll continue to see a faint ghost of it on the screen. I see this most often when I've been in Mac OS X for a few hours, and then I reboot into LinuxPPC -- I can still see the ghost of my Mac OS menu bar at the top of the screen! The ghost stays even if I power down the computer and display for a while. I've been told that the ghost will go away after as much time as it was on the screen to begin with (if the menu bar was there for eight hours, its ghost will fade after eight hours), and that's been borne out by my experience.
How cheap would a B/W printer be?
I see your point, but it depends on what type of printing you do. I work with black and white "laser" printers that cost hundreds of thousands of dollars (I don't really know how much, you'd have to talk to Xerox about the price, the bean counters could tell you though). What, that much? Well yea, but they rip and print 180 pages a minute. They are variable data printing monsters, but if you've got several million b&w unique pages to print, that's what you need.... It's all about finding the right piece of equipment for the job.
1) Minimal demand
2) Lower per unit profit margins
The first problem is that ultimately most people want to buy color LCD panels. It's not worth it to most LCD manufacturers to bother with the small segment of people who would be happy with large black and white LCD panels.
The other issue is that with Black and White, because it is simpler technology, ultimately their profit margins are going to be lower per unit. That means that they have to sell that many more in order to make a profit. If they charge enough to recoup their investment it wouldn't be that much more for people to shell out for the color display.
To see how these economics work, look at the price of processors in the market. There's a certain optimum point where you get a significant amount of power for a low price. If you reduce the power of the chip, the price doesn't drop much because. So you end up in the bizarre situation that you could pick up a K6-300 for just slightly more (or maybe even less) than an old pentium 60. It's just all economics.
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During a trip to the Far East a couple of years back, I was very surprised to see the number of laptops that appeared on office desks. I commented on it to my guide who then pointed out the obvious; Laptops represented a **HUGE** proportion of office desktop market for one very good reason, the amount of desk space occupied is much smaller (primarily because of the screen) and (at that time) there was no other option then to get a "space saving computer" -- the proper name when referring to the laptops over there (which btw, rarely leave the office or even get unplugged).
Further, a friend in Japan tells me that the number of relatively new tube monitors appearing on the street during garbage day has risen dramatically over that last year as everyone is trying to recover a couple of extra square feet and are moving in troves over to LCDs.
Something else to consider is that most applications are not optimized to work in a B/W environment. I know very few developers who have considered, let alone tested the appearance of their applications in a B/W environment. For example, how many developers have a monochrome monitor on their desktop (or even in their dept.) to test against???
Colors, especially monochrome reds/greens/blues appear nearly identical in B/W, yet these are often used together as background/foreground colors in dialogs and are rendered largely incomprehensable in a monochrome environment --appearing as dark grey lettering on a darker greys/black background).
My first laptop 10 years ago was monochrome and the number of times I had problems even then (when monochrome displays were everywhere) was daunting. Yes, if an application is "monochrome" aware you wouldn't have a problem, but the number of apps that fall into that category now has seemingly all but disappeared.
Actually, there are some 640x480 B&W LCD panels, but without backlight. One place that sells them, that I mention only because my brother was looking at them recently, is All Electronics http://www.allelectronics.com The 640x480 LCD panel is $25, not counting material and labor needed to connect it.
Have a nice time.
Yes, things like Linux do have support for a serial console, but that won't help you if you need to get at the BIOS. There are a few BIOS's that support serial consoles too, but they're rare.
And then there's NT. Alas, people do run servers on NT, and NT has no concept of a serial console that I'm aware of.
Hmm.... wonder why TV uses 25 fps and film 24 fps then.
That's the minimum speed, below which we lose the impression of continous motion and start to see seperate images (actually, 18fps is roughly the min -- film was sped up to 24fps so that a soundtrack could be run on the edge of the same piece of film without sounding too crappy). The maximum fps we can discern is much higher (somewhere between 70fps and 150fps, depending on who you ask) -- beyond which point most people could not tell the difference caused by additonal frames per second.
Douglas Trumbull did a lot of research into this area, and created a process called Showscan that uses 70mm film projected at 60fps, which is supposed to look incredible!
Just look away from your TV or computer screen, look out the window and watch the real world, and see how crappy our screens look in comparision. They could be (and will be) a lot better.
I think this is very true. Go to any trade show and the companies are trying to look good. This means all of the slickest hardware they can find. Optical/wireless mice, small keyboards, lighting, and flat screens everywhere.
This Wiki Feeds You TV and Anime - vidwiki.org
In my experience the pixels last a long time. I have a laptop that is over five years old now. It has only one dead pixel which was there from the beginning, and the screen is left on basically all the time. As for my new laptop, it too has one dead pixel which appeared the second time I turned on the computer. I can live with one as long as no new ones appear.
It seems for some reason that one or two dead pixels seem common place, but once the bad ones die off when the monitor is new, the rest seem to last a long time from what I have seen.
Why would you need a console monitor on a server? Run a serial cable from your laptop or pda into the server's serial port / alternate console port and chug away. Here in my office all of my servers are headless and have their serial ports plugged into a portmaster.
We ordered 40 flat panel View Sonics, and 1/4th had to be sent back because of what we called, "Hay Screen" which looks like someone took a fist full of hay and smashed it up against the screen from the inside. With those stats, we expect the rest to fail within the next year or two, after they are out of warrenty. At that point all we can do is throw the $1000 plus monitors away.
I suspect it's because the whole 'LCD on the desktop' industry deal is still very much a special thing for people who want a slick front office. Yes, I know people (more then average around here) use them for solving real problems when a big CRT won't do it, but I'd say at least 80% of units sold goto vanity applications. Vanity means color.
Here's some information regarding ISO standards fro LCD's flat panels. (All this info is from technical documentation I got from Fujitsu-Siemens Computers.)
ISO standard 13406-2 is a completion of ISO 9241-3, -7 and -8, which already regarded LCD's. Classes I to IV are defined in ISO 13406-2.
Class I (theoretical) allows for no pixel faults.
Class II allows for 2 "light pixels", 2 "dark pixels" and 5 "other faults", per million pixels.
Class III allows for 5, 15 and 50 respectively.
Class IV allows for 50, 150 and 500.
"light pixel" is when a pixel is >75% lighter.
"dark pixel" is when a pixel is >75% darker (or "death", I presume).
"other fault" is, well, for other faults (e.g. a subpixel is defect, giving the pixel a distored hue - think color-stuck pixels).
Class II is considered acceptable for office use. Classes III and IV are not.
For a 1,024*768 panel, which is 786,432 pixels, that makes 1.57 light pixels (rounds up to 2), 1.57 dark pixels (rounds up to 2) and 3.93 other faults (rounds up to 4).
This give a maximal number of defective pixels of 8, which is 0.001 % of the screen surface.
This data is very useful when you're a techie on the field and you're being annoyed by some customer who keeps asking for a new monitor because his/her got one or two death pixels. You can tell the monitor still meets the industry standard and therefore will not be replaced.
As for the ViewSonic monitor, I suppose ViewSonic was pretty nice to you when they replaced your "defective" monitor.
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Well, OK, you might not need more than 30 depending on what you are doing, but you can certainly see far higher than 30. You're probably being confused by motion blur. You should also ask yourself whether the concept of 'frames per second' is really applicable to how the human eye works.
Yet no body sells them because they would make less money on them.
I'd rather have someone respond than be modded up.
Actually, what you want is grey scale, not 1 bit Mono.
You can see the effect by taking any BW photo, and convert it to 1 bit color.
You also see this in printing. Laser Print IS 1 bit color, more or less, but you get true photo-grade at about 1500 dpi. Contrast this with grey scale, say on a screen, where 70 - 100 dpi is adequate for a photo, if you are using grey scale. 100 dpi in 2 bit color is horrible.
Check out the Vinny the Vampire comic strip
"It is a greater offense to steal men's labor, than their clothes"
The medical industry uses high-end LCD's in radiology departments. Resolution and brightness are the most important factors and you pay for it. Check out these puppies: http://www.dome.com/products/cx/cxdisplays.html
I'm not sure how todays displays differ from those of older laptops, but I have a PowerBook 170 from almost 10 years ago that is still looking great. At the time we were extatic to have found one with no bad pixels (they were few and far between at the time), and I can say for sure that the same is true of that screen today. It should be noted, however, that that was one of the earliest shipping Active Matrix screens, and monochrome, but it would be hard to find a 10 year old Apple Cinima Display (drool) to check.
Narrative
I can only speak from my own experience: