Talk:TFT LCD

A Suggestion

This entire article is a painful to read wiki disaster. Could someone who knows what they are talking about please fix it and make it not suck so terribly? I suggest that it be eliminated entirely and whatever valuable information it contains could be incorporated into the main Liquid Crystal Display article. Since that one is more active, more knowledgeable people will come across it and fix it up. There is no need for this to be a separate article. —Preceding unsigned comment added by 99.254.49.53 (talk) 09:11, 9 August 2009 (UTC)

Missing overdrive referring

TN panels in 2006-2007 usually include Overdrive functionality to increase response time (2-4ms vs. 8-16ms). This is not even mentioned in this article, not even here: [[1]]

The lowest response time to date is 15 ms overall for the ViewSonic 191b. Numbers in this article are just marketing repeats [2].

Is it really true, that TFT's use CRT technology (first phrase of the article)? Sounds a bit odd. Isn't CRT a competing technology?!

That's a bit like saying that to the apple, the orange represents a competing fruit technology -66.251.26.93 03:22, 25 November 2006 (UTC)

... —Preceding unsigned comment added by 85.53.237.194 (talk) 12:08, 1 March 2008 (UTC)

TFT's do use "black matrix" technology that was originally developed by Zenith for CRT's. In CRT's the black matrix prevents "blooming" the tendency of a CRT to use color purity at high brightness levels. It was a technical response to the Trinitron. Trinitrons also adopted black matrix as without this technology, Trinitrons tended to have color bleeding, especially when showing black and white content. Later LCDs adopted the technology, both to give better definition to LCD pixels and to protect some of the LCD circuitry from photo-induced changes in conductivity... i.e. better color control.

Needs more technical depth

This article needs much more technical depth. It currently looks like a consumer magzine article, and, as such, it contains mostly very time sensitive information. It talks, in qualitative terms about current limitations, but doesn't explain the engineering reasons behind them.

An article that concentrated on the engineering wouldn't date anything like as quickly. --David Woolley 19:53, 17 December 2005 (UTC)

I hope someone knowledgeable on the subject could add a lot of missing information; comparison to CRTs, discussion of limitations, refresh rates, types of interpolations used for non-native resolutions, temporary over- and under-voltaging to achieve faster pixel transitions, standards used in measuring viewing angle and reponse time, future directions... ++Ehudshapira 06:52, 7 January 2006 (UTC)

It would also be good to see how LCD screens compare in terms of power consumption with their CRT equivalents. User:DafDaf 20:39, 13 August 2006 (UTC)

Redone Pic

http://i93.photobucket.com/albums/l52/TheKittenKiller/TFTLCDdisplay.jpg

i photoshop'd it cuz i was bored. feel free to use it and replace it with the image already in use in the main page. Its the same one but with the desk and everything scrapped becuase i think it lets everyone focus on the main subject better and does away with any distractions. KittenKiller

Hi,

I’m the author of the original photo. I’ve just seen the new cropped-version, and I think the only objection of mine to it is the “feathering” of the borders, which could be a little less than the current version.--MaGioZal 01:53, 20 December 2006 (UTC)

Something wrong with these sentences

"There is no or minor effect on the eyes, if we use TFT-LCD monitors." Does this really belong in the introduction paragraph? It seems kind of out of place to me, especially as a single sentence paragraph. Also, the use of "we" is improper for an encyclopedic article. -70.74.135.191 17:19, 28 October 2006 (UTC)

"Usually with 3 data signals and one clock line." is found in the "Electrical Interference" section. Anybody know where this belongs? --Calcvids (talk) 02:39, 30 June 2010 (UTC)

Clarification please

"the pixels are addressed in rows and columns which reduce the connection count from millions to thousands. If all the pixels in one row are driven with a positive voltage and all the pixels in one column are driven with a negative voltage, then the pixel at the intersection has the largest applied voltage and is switched. The problem with this solution is that all the pixels in the same column see a fraction of the applied voltage as do all the pixels in the same row, so although they are not switched completely, they do tend to darken. The solution to the problem is to supply each pixel with its own transistor switch which allows each pixel to be individually controlled."

This extract does not satisfactorily explain how the addressing of an individual pixel can be achieved without seriously interfering with other pixels. Each pixel has its own transistor switch, but how is that switch itself addressed individually? In the extract the problem is merely deferred, not solved. Also, if a particular row experiences a positive voltage and a particular column experiences a negative voltage, then the pixel at their intersection is at zero voltage. Could an expert rewrite this section please? - AG, Stockport, UK.

>>Attempt at clarification<<< This is sort of a guess, but if you had a layer of horizontal wires, then a layer of 'fancy liquid crystal stuff that lights up when current flows across it', then a layer of vertical wires, and then if you connected one of the horizontal wires to 'live' (+volts), and one of the vertical wires to 'earth' (-volts), then wouldn't you get current flowing across the blob of 'fancy liquid crystal substance' at the intersection making it light up? The current would flow along the wires to get to the intersection, so the rest of the liquid crystal stuff in that row and column wouldn't be affected. Doesn't it work something like this? —Preceding unsigned comment added by 212.183.140.33 (talk) 10:07, 18 January 2010 (UTC)

/MASSIVE FACEPALM. Basic transistor addressing, same as in, e.g., a keyboard. The transistors, or more accurately the liquid crystals have some persistence and inertia between the times that they are individually and intensely addressed, for a fraction of a microsecond every 16 milliseconds or so. Consider a simple 8x8 grid, with 64 greyscale pixels in it, but only 16 incoming connections. To have any (Liq Crys-affecting) output from a particular transistor (at the emitter), both of its two inputs (base and collector, or in other words "control input" and "controlled current source") have to be activated - one to provide the actual power, and the other to regulate it i.e. open the tap. So, you could have all the bases as the horizontal input wires, all the collectors as the vertical ones, and the emitters grounded to a backplate via the actual LC pixels. You then apply, with a slow switching rate (8x per frame refresh), steady current to each single collector line in turn, activating that "row". Within each row's active time, you apply variable voltage (representing the output brightness you desire for each pixel of the row) to each base line in turn, at a higher switching rate (e.g. here, 8x for each row, or 64x for each frame). Each transistor is then individually activated and sends a controlling pulse to its corresponding crystal.

There was some variation on this, I assume, with the old single & dual-scan type screens, which had very noticable ghosting and leakage, with faint trails going from the edges of any major on screen element in a straight line to the top/bottom/sides of the screen (or the respective half of it), or at least just poor quality circuitry and leaky transistors. TFTs haven't displayed this dubious quality for quite some time, since whatever the particular magic in "active matrix" screens came along. I think it may be that it was the crystals themselves that were hooked up matrix-fashion (so all the crystals in a row were slightly influenced by large signals going to one of their number, but only the ones which had two coinciding pulses experienced a large change - not so much of an issue when you were only talking flat monochrome, 16 greyshades or 256 colours out of ~4096 FRC'd & dithered to 262k), with only a small number of external transistors, and active matrix actually put transistors on each individual pixel to improve things in the same way that they do for radio reception.

^^^ from this, in either type, further simplification can happen outside of the panel with additional matrixing of the input lines - so, for example, a 1024x768 screen will only have a total of 28 inputs needed from a master controller (10-bit for vertical dimension, 12-bit for horizontal including subpixels, and 6-bit for the actual intensity) rather than a spaghetti-like 5376 with a pile of digital-analogue converters; and the input to the master decoder chip itself could even be single-bit serial, with a very fast switched line (1.14Ghz for XGA, 24bit, 60Hz) with a load more matrixing and demultiplexing taking place within its PCB. 193.63.174.10 (talk) 10:14, 10 May 2010 (UTC)

FFS?

I remember seeing a section about FFS(Fringe Field Switching) along with other technologies like TN, IPS and MVA/PVA. But it's gone and I can't find it in the history. What happened? 1wonjae 07:00, 4 September 2007 (UTC)

Toxicity

Saying LC's are poisonous may be a gross oversimplification. While it's probably a good general policy to clean up any LC material from your skin; it might be alarmist to say that LC's are entirely poisonous. Here's one article from Merck that shows that most of the LC's that they have tested are non-toxic: http://www.merck.de/servlet/PB/menu/1119540/index.html 64.25.15.162 23:33, 24 October 2007 (UTC)

Totally agree, have added reference to Merck's toxicity report. panjasan (talk) 14:29, 14 August 2008 (UTC)panjasan

Added a contradictory tag/template to the safety section. Are they toxic or not?89.217.64.142 (talk) 17:52, 17 February 2012 (UTC)

Mobile phones

What about TFT displays in mobile phones? This would be nice to add at least few sentences aout this topic. —Preceding unsigned comment added by Varciasz (talk • contribs) 22:39, 10 February 2008 (UTC)

They're just small versions of the existing laptop ones, really... though they're catching up in terms of resolution. Tended to be a little more crude and cheap, ie chunkier pixels, only 512- or 4096-colour gamuts etc (or indeed, monochrome/low-bit greyscale), but not so much any more.

Do wonder what the tech behind early mobile colour screens such as the Game Gear, pocket TVs etc was, though - several of which were on sale before colour screens became at all popular for "real" computers. (and quite what kind of strange proto-FRC was going on with the flickery but almost photo-real intro screen to Super Monaco GP) 193.63.174.10 (talk) 09:42, 10 May 2010 (UTC)

TN Panel Section Biased

The section on TN panels seems quite negatively biased against the technology. I agree that more technical depth needs to be added to the article as a whole, but certainly the TN panel section needs a reworking entirely. It merely lists the failings of the technology, and none of the strengths.

"These panels can display interpolated 24-bit color using a dithering method which combines adjacent pixels to simulate the desired shade. They can also use FRC (Frame Rate Control), which quickly cycles pixels over time to simulate a given shade. These color simulation methods are noticeable to most people and bothersome to some"

This particular excerpt is outdated, as many TN panels employ much more advanced and complex dithering methods now to produce a much better colour gamut.

I would update the section myself, but I feel my expertise on the subject are a little lacking, and my input would therefore be too inaccurate for an online encyclopedia such as this.

• I don't see why the first paragraph in the TN section was deleted (May 8)... I'm restoring it, if only for the part that says what TN is and links to it. —Preceding unsigned comment added by 70.109.59.173 (talk) 20:48, 18 May 2008 (UTC)

"FRC ... bothersome to some" may still very well be true. I think it may be an important factor in overwhelming distress described here and at other similar discussions. Unfortunately I do not know any study which would deal with FRC and eye fatigue (and confirmed that small percentage of people is extremely sensitive to it) but I think FRC may quite well be that hidden mystery which irritates eyes of some people despite their vain attempts to adjust contrast, ambient light etc.etc.--Vaclav.hanzl (talk) 16:08, 19 December 2009 (UTC)

I'd definitely leave it in, because there are still screens around that offer far from perfect FRC. Can't remember where I was seeing it (work? shop?), but I've seen in the last week a sub-year-old flat panel that had very obvious banding and flicker (looked almost like analogue TV signal snow in fact). My own workstation monitors are better, despite one being built-in and the other a complete random; either they've got full 8-bit (or more) gamut, or FRC/dithering/etc sufficiently advanced that even when looking very closely it's not discernable.

Don't fall into the trap of the writer of another article I've seen on the subject, that you assume because you can't detect it on your screen with Windows set to 60Hz, that "the human eye cannot see FRC flicker at 60Hz". Oh, it most certainly can. Anything below about 90Hz is detectable to varying degrees depending on the sharpness of the viewer's eyes (I can tell about 80-ish), and if you're having to integrate across 3, 4 or more frames - as would be needed to simulate 8-bit channels with 6-bit subpixels - you'll want progressively higher rates than even the 100~120Hz required to add one extra bit to each channel's depth. Only the latest 480 and 600Hz panels could really be trusted to achieve such things, but I'd hope they're managing a native 8-bit or higher in the first place. (It's not impossible; there are - very expensive! - medical imaging flatpanels with true 10- or 12-bit/channel depth (albeit some of them having to be greyscale, ie single channel), so why can't consumer grade models do this, allowing for e.g. more accurate gamma adjustment?) 193.63.174.10 (talk) 09:52, 10 May 2010 (UTC)

Wall Mount Holes

I wish to know about those screw holes in the back of a tft screen you can use to attach the screen to a wall mount. Is this a industry standard? Does it have a name? It's just that I would like to search for this industry standard for devices I can attach to the back of the tft screen (routers,hubs, micropc's, etc) Can this info be added here? Or perhaps a link to a page about this standard? --82.93.172.114 (talk) 09:21, 2 July 2008 (UTC) Try VESA standard at www.vesa.org 86.142.42.20 (talk) 15:46, 6 August 2008 (UTC)

IPS

How exactly is "Still some backlight bleed in areas that are green" a con of H-IPS over S-IPS? Seems like there was a complete idiot writing text on this article. It shows complete lack of thinking and amazing stupidity. Furthermore, the article fails to disclose what the H in H-IPS stands for. Extremely lousy quality! --84.250.188.136 (talk) 21:49, 14 August 2008 (UTC)

The contents of the tables in the IPS section are total rubbish, and in its current state should be removed. the e-IPS section is ridiculous; so far one blog spoke of increasing backlight efficiency by increasing, rather than decreasing aperture ratio which itself is a dubious claim. I assume the person responsible for the entry managed to misinterpret an unreliable source. As far as i know, the CCFL backlight of an LCD monitor is responsible for determining gamut, rather than the matrix itself.

I agree, it is rubbish and reads more like a blog entry then what an encyclopedia should be. "IPS technology is widely used in panel sizes of monitor 20"~30" and LCD TV 17"~52"."  ??? There are in the current market place, 3? LCD panels that utilize this technology vs. generally accepted TN.

e-IPS does not have a reduced contrast ratio. Where did the writer canvass this from?. the e-IPS dell 2209WA was benchmarked at around 850:1 CR when calibrated, approximate to the H-IPS nec LCD2490WuXi. --124.169.112.11 (talk) 21:31, 26 April 2009 (UTC)

I might add that the first table is in a better condition than the second.--124.169.112.11 (talk) 21:47, 26 April 2009 (UTC)

HP Website sais its Panel isn't H-IPS but S-IPS. (source: http://h10010.www1.hp.com/wwpc/de/de/sm/WF06a/382087-382087-64283-3884471-3884471-3648442.html) Anyopne more Information on that? —Preceding unsigned comment added by 87.187.89.153 (talk) 21:42, 16 August 2009 (UTC)

Doesn't e-IPS mean "economy IPS" and not "enhanced IPS" like it is stated in the article? There is nothing enhanced as I know. It's just cheaper. —Preceding unsigned comment added by 62.224.76.103 (talk) 13:03, 8 September 2009 (UTC)

I'm not sure quite where it would fit in, but Apple's iPad utilizes In-plane switching (IPS) technology. This should be included in the page. I don't know what type of IPS, but that's it. And it's big. —Preceding unsigned comment added by Billselak (talk • contribs) 22:43, 27 January 2010 (UTC)

To individuals who are graphic artists, IPS is superior to the exactness of color reproduction and image contrasts. These monitors are expensive and to the discerning eye you put one next to a TFT or a TN panel monitor it is very obvious the IPS based panels are far more brilliant. —Preceding unsigned comment added by 65.207.221.99 (talk) 10:50, 7 August 2010 (UTC)

The part about H-IPS panels from NEC (LG) having "Advanced True White" (A-TW) polarizing film is wrong. It's also probably wrong that the polarizing filter is from NEC, they just implemented it in some of their monitors. It stands for "Advanced True Wide" and it was implemented in just a couple of models (NEC MultiSync® LCD2090UXi, NEC MultiSync® LCD2490WUXi and NEC MultiSync® LCD2690WUXi come to mind). A few other models from different manufacturers can be found online. The advantage was greatly reduced "IPS glow". The disadvantage was green and purple hue on black when viewing from extreme angles. They stopped using it because: "It has been discontinued and is no longer available from the supplier." as stated on the official necdisplay.com website in the FAQ section. Hence why "polarizing film from NEC" is probably wrong. Funnily enough, they specified the A-TW abbreviation there as "Advanced True White". Datasheets say otherwise and it's also logical, based on the purpose of this polarizer. It has nothing do to with white output of the display. — Preceding unsigned comment added by 88.212.37.209 (talk) 12:27, 27 September 2020 (UTC)

toxicity report link not available...

the link: 092002.pdf is not found. author to this reference please help to check.
Xmlv (talk) 07:53, 4 September 2008 (UTC)

fixed: [3]...? --Homer Landskirty (talk) 08:59, 8 August 2009 (UTC)

Vertical viewing angle

Every laptop I've seen to date and by far most computer displays suffer from major contrast change depending on the vertical angle of view. As the article notes, Apple's 24" aluminum iMac does not suffer from this problem. Apple's 25" glass-fronted LED Cinema Display and its other matte-finish aluminum displays are also excellent in the vertical angle department. What exactly is this great LCD technology that has no problem with vertical angle? Why is it not used in laptops?

Dave Yost (talk) 01:33, 25 October 2008 (UTC) My Samsung 305t does not have this problem. 64.246.157.194 (talk) 06:18, 21 April 2009 (UTC)

While there were a few laptops in the past that used something other than TN panels (certain IBM Thinkpad models), as far as I'm aware all current laptops are going with TN panels - they're cheap and readily available. So when people bash on TN panel technology, that's what they're complaining about. --Jarred Walton (www.AnandTech.com) —Preceding unsigned comment added by 24.18.109.14 (talk) 07:14, 17 June 2009 (UTC)

I am not aware of any laptop offering an IPS based panel, and even if they did, it would add to the cost significantly. I wish they did offer the option. —Preceding unsigned comment added by 65.207.221.99 (talk) 10:55, 7 August 2010 (UTC)

Matsushita is no longer known as Matsushita.....

Matsushita officially changed the company name last year to Panasonic and all products produced are made under the Panasonic name. —Preceding unsigned comment added by 24.26.83.214 (talk) 05:09, 9 June 2009 (UTC)

Safety

I've significantly changed the 'safety' section. This is because it was nonsense before; it claimed LCDs were poisonous, and that medical attention ought to be sought after contact. The reference cited did not say any such thing. Further, a report from a major manufacturer of LC that was cited stated that all marketed LCs are almost completely non-toxic. If the manufacturer's article is to be used as a reference, then we ought to do justice to what it says: that is, that LCs are not toxic.163.1.18.244 (talk) 11:01, 24 October 2009 (UTC)

BIg user of IPS

All macs have IPS screens from LG, which must be notable. http://lowendmac.com/newsrev/09mnr/1030.html under the 27" mac has no pc equal, also other places I've forgotton. 86.139.101.41 (talk) 14:17, 30 October 2009 (UTC)

No they don't. The last generation 20" iMac uses a TN screen whereas the 24" uses IPS (and the Mac Mini and Mac Pro doesn't have a screen at all!). --antilived^{T | C | G} 18:46, 30 October 2009 (UTC)

in-plane switching redirects to here

Can we move in-plane switching to its own article? Mathiastck (talk) 00:23, 28 January 2010 (UTC)

In plane switching was actually invented in the US by RCA by Joe Castelano, who does occasionally make Wikipedia contributions. If you contact him directly, he might write a technical history. He is also extremely familiar with the other technologies. Norm Hairston

WRONG: The First appearance of IPS Technology to consumers was released in iPad by Apple April 2010.

I'm not sure what the first appearance of IPS technology was. But it wasn't the iPad.

According to Apple, the latest iMacs use IPS months earlier than the iPad.

http://www.apple.com/imac/specs.html —Preceding unsigned comment added by Psimin (talk • contribs) 03:44, 13 March 2010 (UTC)

Sounds reasonable - the newer generation of Macbooks that came out a few months ago had vastly improved screen quality (though it only really came up to that of higher-end PC ones from a couple years previous), and as noted above, the units were made by LG... who surely would have used the tech first in their own products before selling it at component level to other manufacturers. Plus I've seen people recommending purchase of IPS-based televisions on messageboards for some time now. It's just yet more idiot hype about the iPad, aka Macbook Air Slate Supercutdown. As it's at XGA rez, and doesn't retail for THAT much money, why suspect it uses anything other than a typical-spec low-area laptop panel? (There's an old Slate PC around here somewhere that probably comes close to the colour quality but at SVGA rez, and not that much thicker either). It seems to be quite a good device that will find, at least, a lot of use in some important, professional niche areas (and a lot of idle noodling by magpie consumers), but don't take the mickey. 193.63.174.10 (talk) 09:28, 10 May 2010 (UTC)

IPS has been around since 1996, although Apple is one of the first manufacturers to adopt the technology in their monitors the article was written wrong. The iPad is probably the first portable in the laptop family to use IPS. I have not seen other manufacturers of laptops or tablet based computers use IPS, but I wish they did offer the option. —Preceding unsigned comment added by 65.207.221.99 (talk) 11:01, 7 August 2010 (UTC)

What is TN+?

195.241.233.20 (talk) 14:20, 8 June 2010 (UTC)

Types

It might be helpful to include the years (or month/year) that each of the types were released to the market, as well as when they were (and/or began) develop(ed/ment). From the descriptions alone of each type, I wouldn't be able to tell if each came out last month or last century. — al-Shimoni (talk) 14:18, 6 July 2010 (UTC)

Super LCD

"Super LCD" links here, but isn't named on this page. Is it the same as super TFT? PizzaMan (talk) 07:49, 29 August 2010 (UTC)

History? What history?

The "history" section links back to what is essentially a long string of pictures with links to the pages corresponding to the display types that the pictures illustrate. It contains no actual information for this type of monitor, only a link back here. Click you're there, click you're here. 2-link empty loop. I do not know the history, that's why I came here looking. — Preceding unsigned comment added by Sourisvoleur (talk • contribs) 17:31, 14 January 2013 (UTC)

AHVA

BenQ has announced the monitor BL2710PT with AHVA display 85.235.164.186 (talk) 10:36, 19 June 2013 (UTC)

LED IPS

"LED IPS" is redirected to this page, but there is no mention of LED technology anywhere on the page. Why is that term redirected here?76.21.162.115 (talk) 07:15, 4 May 2014 (UTC)

I think we should remove this redirect. The confusion exists, because many LCD TVs are advertized as LED TVs, because they have LED backlighting. However, IPS has only a meaning as a type of LCD electro-optical effect.

BBCLCD (talk) 20:02, 4 May 2014 (UTC)

Have removed redirect from LED IPS.

BBCLCD (talk) 19:37, 6 May 2014 (UTC)

History

During 2017, the section on the history of TFT LCDs has been added based on Japanese contributions only. Although the Japanese industry played an important role at the time (in particular Seiko Epson, Sharp, Hitachi, Casio), claims about inventions are questionable. In the Western world, credit for the TFT invention and early prototyping is given to a team at Westinhouse Research Laboratories headed by T. P. Brody in the USA. IEEE as the most reputable international technical organization in the field, has awarded the 2011 IEEE Nishizawa Medal to three inventors working in the US at that time.

In addition, users 86.173.191.95 and 109.155.237.165, who did recent revisions to this section, have been declared sock puppets of a banned user on 8 May 2017. Therefore, user:Indrian has eraesed the corresponding parts in lemma "Liquid Crystal Display".

I plan to correct this section on the history of TFT LCDs. BBCLCD (talk) 07:24, 9 May 2017 (UTC) BBCLCD (talk) 08:56, 9 May 2017 (UTC)

• Thank you for calling this to my attention. The edits have almost certainly been made by banned user Jagged 85, who is known for making rapid-fire sourced edits to technology articles with an emphasis on crediting Non-Western sources for various inventions when the sources in question do not, in fact, support his positions. More info on his past misdeeds can be found at Wikipedia:Requests_for_comment/Jagged_85/Evidence and Wikipedia:Requests for comment/Jagged 85/Computer Games Evidence. He comes back every few months, usually in the 86 IP range, but more recently also in the 109 range, and many of his edits continue to be inaccurate. I try to revert when I can. Indrian (talk) 20:40, 10 May 2017 (UTC)

TFT Panel

Somthing more details 103.218.237.36 (talk) 19:08, 26 December 2022 (UTC)