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Thread ID: 34266	2003-06-08 11:22:00	The future of monitors, TFT or Plasma?	rugila (214)	Press F1

Post ID	Timestamp	Content	User
150970	2003-06-08 11:22:00	I’ve been thinking about this a bit. It’s easy to be impressed by the size and quality of display of good plasma TV screens. It’s likely that CRT monitors (and maybe CRT for TV also) has passed its heyday and has little scope for further technology development or cost reduction. As of now it seems that either plasma or TFT (i.e. advanced LCD technology) is likely to be the future direction. Both have relative advantages and disadvantages and well as both having flat and thin display panels that (unlike CRT) don’t fire beta rays at your head from short range. Plasma screens have better viewing angles and are currently significantly cheaper (per unit area) in the larger sizes. TFT is currently very expensive above 24” or so. As of now TFT is probably the better choice for computer screens , and there doesn’t seem much available in the way of plasma computer screens anyway. But for the future … it should be an interesting competition in technology improvement and cost reduction. (CRT originated by William Crookes about 1870. Plasma from Univ of Illinois about 1964 LCD from HP about 1968 But, as with most else these days, you can get more accurate chronology from Google)	rugila (214)
150971	2003-06-08 12:22:00	I think another couple of years to see a definite direction.	Thomas (1820)
150972	2003-06-08 12:30:00	You will certainly see a decrease in CRT's from now on as 15" and 17" LCD's have dropped to a more acceptable price. When you consider that the resolution of a 42" plasma screen is only around 1024 x 768, (or the same as a 15" LCD) however you will realise that technology must mature a lot before it can be useable as large screen monitors for PC's. There is a lot of space between pixels on a 42" Plasma screen... LCD will struggle for cost at larger sizes but technology will deliver to both possibilities.	godfather (25)
150973	2003-06-08 12:32:00	> You will certainly see a decrease in CRT's from now > on as 15" and 17" LCD's have dropped to a more > acceptable price. That may be true, but remember you are buying an LCD with an estimated life of only 20,000 hours whereas a CRT is supposed to be 60,000 hours?? Someone correct me if I'm wrong here... Either way, I think my next purchase will remain a CRT until LCD's are ridiculously cheaper than a standard CRT... mind you, a dual 19inch LCD display would be oh so sexy.... :x Lo.	Lohsing (219)
150974	2003-06-08 12:45:00	Plasma will be the king in the end I think. But at the moment CRT is where it is at. Go compare a VERY high quality CRT TV to a Plasma one. I know which one it will be. There's been 30 years of development gone in to CRT so of course it will be better at the moment. Give it time and Plasma will be the one to have I think.	-=JM=- (16)
150975	2003-06-08 12:47:00	Yes the hours are correct as far as I know. At 8 hours per day, 5 days per week thats 10 years though. How many CRT monitors are still in use after 10 years, and do you really think thats a limitation? >mind you, a dual 19inch LCD display would be oh so sexy My dual 15" LCD display is pretty good, the primary display is DVI driven as well, which really allows it to show its advantages.	godfather (25)
150976	2003-06-08 13:37:00	I don't know the expected lifetime of LCD monitors, so had a bit of a look through Google for curiosity . A few comments, copied and pasted, are: (a) • LCDs—The average expected life of an LCD backlight is 25,000 to 30,000 hours . This represents three to four years of use for a display operating 24 hours a day, seven days a week . The back-light of an LCD can be replaced economically, prolonging the life of the display . • CRTs—The average expected life of a CRT is 12,000 to 15,000 hours . This represents one and a half to two years of use for a display operating 24 hours a day, seven days a week . It is rarely economical to replace the tube within a CRT . (b) Specifications: LCD Panel - Screen Size: 304 . 1(W) x 228 . 1(L)mm (15 . 0") 381mm Diagonal - Aspect Ratio: 4:3 - Resolution: XGA 1024(H) x 768(V) - Pixel Pitch: 0 . 297(H) x 0 . 297(V) mm - Brightness: 400 cd/m2 (Typical) - Contrast: 500:1 (Typical) - Viewing Angle: 60(R) / 60(L) / 50(U) / 60(D) - Response Time: 6(Tr) / 22(Tf) ms (Typical) - Expected Life Time: 50000hr (Min) @ 6mA (c) LCD/TFT Lamp Life: Expected life of backlight lamp is 60,000 hours, this equates to ten hours use a day for more than sixteen years . (d) LCD manufacturers claim figures between 50,000 and 75,000 hours for LCD monitors/TVs . An LCD can last as long as the backlight (and backlight bulbs can actually be changed out) . This is because the light is passing through a prism effect of the liquid crystal to produce the light and color . It's a substrate so there is nothing to effectively burn out . I suppose that improved technology over time may make them last longer than the earlier models, but manufacturers (incl of software) can be pretty good at planned obsolescence, so I don't know .	rugila (214)
150977	2003-06-08 21:45:00	The main problem with LCD displays is still the refresh rate and the ability to rapidly update (for games etc.)... until they fix that problem the CRT will be king of the gamers I'm sure. Mike.	Mike (15)
150978	2003-06-08 23:01:00	> Both have relative advantages and disadvantages and > well as both having flat and thin display panels that > (unlike CRT) don’t fire beta rays at your head from > short range. ?:| News to me Rugila. There is nothing in a CRT monitor capable of generating beta rays. They are generated by the decay of radioactive substances and there is nothing like that in a CRT. Even X-ray levels are below background radiation levels. X-radiation from CRT monitors is measured as the kerma rate in air in units of gray per hour (Gy/h) The spec for CRT monitors is <5000 nG/h (<5µG/h) but MPR & TCO testing has yet to find any monitor with measurable X-ray emissions. If you check the spec for any monitor, if they bother to record it at all it will be shown as <100 nG/y which is the normal background level in their testing laboratories. I just ran alpha, beta and X-ray checks on my Hyundai monitor and got a zero response. However, sitting in my office I can still record background gamma particle strikes. > Life expectancy of CRTs—The average expected life of a CRT is 12,000 > to 15,000 hours. This represents one and a half to two years of use for > a display operating 24 hours a day, seven days a week. It is rarely > economical to replace the tube within a CRT. The life expectancy of a CRT in continuous use (for acceptable image quality) is closer to 25,000 hours or approximately three years. This is borne out by experience in 24-Hr call centres and the like where the monitors are never off and they never go into standby. In my experience, 19" & 21" monitors will probably show some deterioration at 3 years but 15" & 17" normally last over 4 years in this use. LCD's will rule once production yield improves as (IMHO) it will take time for plasma to achieve adequate definition standards. Plasma also suffer a progressive loss in light output over a "shorter than CRT" lifespan and will not be viable for continuous use for TVs even until they get that under control because of the horrendous replacement costs. Cheers Billy =8-{) [pre][b]Checking background radiation levels always makes my hair stand on end. I like to kid myself that the cosmos will leave me alone if I don't think about it. :^O	Billy T (70)
150979	2003-06-09 00:40:00	Billy T Thanks for your interesting contribution . It’s really great to see scientific originality in action . Actually, I could give you a few dozen references, although a brief look through Google would be quicker, that beta rays are electron streams, nothing more and nothing less (other than the name) . (Electrons were – most scientific stuff says discovered, philosophy stuff rather takes the view they were invented – by J J Thomson in 1897, who was later given a Nobel prize for his work . ) You’re right that beta rays/electrons are generated by radioactive decay . But they’re also generated by quite a variety of other means . You’re 100 percent wrong when you suggest there’s nothing in a CRT to generate them . CRT’s have a “gun” at the back firing electrons/beta rays at a phosphor-coated screen which glows appropriately so you can see the outcome . If CRT’s didn’t have this beta ray/electron stream generating device they wouldn’t work, in fact they wouldn’t even be CRT devices . Summary – if you use a CRT you do have some of the stuff which is also generated by radioactive decay firing directly at your head at close range . One certainly expects and hopes that most (all?) are absorbed by the phosphor coating before they reach you . You personally may be happy with your implied gamble that your detection instruments are able to monitor the effects of this on your brain over 15 or so years use to ensure you won’t eventually finish up with brain tumour or similar, but it’s not a bet I personally want to take, particularly since better (in a number of ways) technology is available . Please forward me $5000 plus GST as a physics/philosophy and medical advice consultancy fee . Refundable in full if you can show that any of my information above is incorrect . Regarding your comments on the life of CRT tubes (as opposed to the life of those sitting closely in front of them) I don’t have any opinion or detailed information . If you dispute what was in my earlier post on this you are disputing Google, not me, since I only reported a quote .	rugila (214)
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