Talk:Liquid crystal display

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Contents

[edit] "Calculating Threshold Voltage"

The applicable formulas would be nice to have here...I'm looking them up in papers now but cant find ones that relate the gap distance between the electrodes. —Preceding unsigned comment added by Syanchuk (talk • contribs) 15:57, 30 April 2008 (UTC)

[edit] "Whats a smoot?"

Vertical ridges etched on the surface are smoot.

A unit of length equal five feet seven inches? I don't think this is what the original author meant.

[edit] "Before applying an electric charge..."

This paragraph begins with the following two sentences:

Before applying an electrical charge, the liquid crystal molecules are in a relaxed state. Charges on the molecules cause these molecules to align themselves with microscopic grooves on the electrodes.

On my first read through, I was under the impression, for the remainder of the paragraph, that the "Charges on the molecules" were ones applied by an electric current. It's been a while since I studied physics, but would it still be scientifically accurate if we changed the wording to say "Naturally occurring charges on the molecues"? I think that would be easier to understand. Balfa 13:15, 21 August 2006 (UTC)

[edit] chemical used as crystals

I would like to know what chemicals are used as crystals to twist the rays --213.67.44.59, 25 July 2004= miaminarals

What types of crystals are used in LCDs? --128.112.33.111, 30 August 2004

I would recommend looking through the US Patent System, or other patent systems, for some of the patented pixel formulae. In the US system the class 349 deals with liquid crystal cells and should have patents related to the chemicals used. The Internation classification G02F 1/13 or 1/133 might have information on it as well. These would probably be some of the best sources at least to start. -- Thebdj 15 December 2005

[edit] Merge to/merge from dead pixel

Thanks to muggins not noticing the info on quality control here, there's now a page called dead pixel. There's some vaguely useful info and a neat-o outside link there, so will we merge the Quality Control section here into that article, or vice versa? Sockatume, Talk 19:10, 2 Jan 2005 (UTC)

The decision hinges on whether it is a dicdef, or if it has enough content to sustain itself as an article on its own. As dead pixels are only related to LCD's, but aren't LCD's themselves, I suppose we should keep them separate. Kareeser|Talk! 02:07, 22 May 2006 (UTC)

[edit] Substrate sizes

How about a section on glass substrate sizes (generation 3 to recently announced 8)? -- Toytoy 14:05, Jan 25, 2005 (UTC)

[edit] Ridges

rigdes means some irrespective waves and it can be filtered by using vertical filters --vignesh babu.N.M.(MCA), 26 October 2005

[edit] LCD windows

Some text on "LCD windows", which can be opaque or transparent ala "True Lies" movie would be appreciated -- 172.146.145.103 1 December 2005

[edit] amount of light absorbed

The Text claims that apart from only a small amount of light being absorbed by the polarizing filters the entire assembly is transparent. But to my understanding the light transmitting through or emitting from an LCD is always polarized (which can be checked by looking at an LCD through such a filter)and a polarization filter absorbs "wrongly" aligned waves (my physics are a bit fuzzy there). As I don't know polarized lightsources (could be wrong there aswell), the minimum absorbation rate would be 50%, where it didn't matter whether the light passed through once or twice. All this is more or less based on my observation of my bedside alarm clock being far from transparent. -- 84.150.15.168, 11 January 2006

[edit] problem fixes

can we please fix this section by editting it into a real encyclopedia style please. a listing of the problem and how you might fix it should be sufficient and it isn't that hard to change. We do not need text from a forum in a wiki article, this is not a self-help page, but an encyclopedia entry and it should be written that way. -Thebdj 06:26, 9 February 2006 (UTC)

Yes, you're right. Corrected. --Fractal3 06:39, 25 March 2006 (UTC)

[edit] Wikipedia is not an instruction guide

"Workarounds and/or possible fixes for LCD problems" - This doesn't belong in an encyclopedia. -- 63.114.24.9, 25 March 2006

obviously the best result would be a poll to ultimately decide. I'll deal with this later. /Fractal3 00:46, 31 March 2006 (UTC)/

[edit] WinXP ClearType?

Should Windows XP ClearType really be mentioned in the drawbacks section? Only mentioning it gives an impression of it being the only subpixel text rendering technology out there. I think a more generic term would be more appropriate. Lumpio- 16:01, 12 April 2006 (UTC)

[edit] This article is displayed in a product review of an LCD monitor

Wikipedia's liquid crystal display article is the content which is displayed on an LCD monitor under product review.

I took a picture of the illustration, but what's the point. It's the same picture as on the article page, but framed in an LCD monitor. --Ancheta Wis 01:51, 8 May 2006 (UTC)

[edit] Don't merge this article

It's completely separate from the general LCD article and is useful for a casual browser like me. please don't merge it 203.129.39.114 13:21, 20 May 2006 (UTC)

[edit] Proposed Merge of Color LCD to LCD

I propose that we merge Color LCD to this article, simply because the information contained in the Color LCD article is too short to have a "Main aticle" link from this page. Moreover, the content on this page (in the "Color LCD" section) and the content on the Color LCD page, differ. Therefore, having the same information on this page, while making Color LCD a redirect, is my solution. Kareeser|Talk! 02:05, 22 May 2006 (UTC)

Agree LCD isnt that long, it can definitly support everything in Color LCD. -Ravedave 02:50, 22 May 2006 (UTC)

Just delete the Color LCD article, it's useless...

Redirected. If there is anything in Color LCD that isn't here - it can be merged from the history. ed g2s • talk 08:53, 18 June 2006 (UTC)

[edit] Glossy LCD mention

I think it would be useful to talk about glossy LCDs (XBrite,TruBright and so on), since they're very frequently used today. I found this page which explains something about it: http://www.screentekinc.com/sony-xbrite-lcd-screens.shtml

Blaisorblade 23:08, 24 May 2006 (UTC)

[edit] Different types of TFT LCD pixels

The following image shows that not only straight pixels (columns of liquid crystal molecules) are used. Normally pixels should be shaped vertically, but these are shaped like a ">".

">" type pixel. Picture part of a Dell 1905FP TFT LCD display.
">" type pixel. Picture part of a Dell 1905FP TFT LCD display.
This kind of pixel-layout is found in S-IPS LCDs (super in-plane switching). The chevron-shape is used to widen the viewing-cone (range of viewing directions with good contrast and low color-shift).

panjasan 16:49, 25 March 2007 (UTC)panjasan

[edit] License and link position

Someone could check the license and if allowed copy some basic information about sane transflective usuage to the wiki. related Link: http://www.walkermobile.com/OutdoorDisplayPrimer.pdf

[edit] transflective vs. transreflective

I think these terms are equivalent. I started a new article on "transreflective" when I stumbled across the mention of "transflective" in this article on LCDs.

The valuable PDF by Geoff Walker at http://www.walkermobile.com/OutdoorDisplayPrimer.pdf is now almost 2-1/2 years old. There's a nice definition of transreflective at Smart Computing. There are excellent images at http://t17.net/transflectiveTFT/

[edit] Drawbacks and Advantages

  • I think the following can be deleted:
    This text from the Drawbacks section first mentions response times then goes on to say that it is imperceptible. If it is imperceptible then it is no longer a problem. Am I missing something?

LCDs have longer response time than their plasma and CRT counterparts, creating ghosting and mixing when images rapidly change; this drawback, however, is continually improving as the technology progresses and is imperceptible in current LCD Computer Displays and TV's. Also, for computer-use, it eliminates the problem of flicker.

Ashmoo 03:48, 7 August 2006 (UTC)
Changed "imperceptible" to "almost imperceptible". You may also want to mention that whether you notice it depends on what you are doing (viewing fast moving images, etc). mmj 11:48, 15 August 2006 (UTC)
I don't know that I'd call it "almost imperceptible". I recently got an LCD TV (with a claimed response time of 8ms). When viewing rapidly panning images (the best example is to fire up a first-person shooter on a game console and manually pan left and right), the ghosting was not only perceptible, but thoroughly irritating and almost nausea inducing. I would definitely recommend adding to the article that the effect of long response times depends on what you're viewing. Balfa 17:33, 21 August 2006 (UTC)
  • There seem to be some problems with the drawbacks page.
  1. Why can't the last drawback(possible inability to display 320X240) be merged into the first? (first deals with inability to display resolutions not a multiple/fraction of original resolution.)
  2. The following seems to contain information which should be mentioned elsewhere in the article:
    The viewing angle of a LCD is usually less than that of most other display technologies, thus reducing the number of people who can conveniently view the same image. However, this negative has actually been capitalized upon in two ways. Some vendors offer screens with intentionally reduced viewing angle, to provide additional privacy, such as when someone is using a laptop in a public place. Such a set can also show two different images to one viewer, providing a three-dimensional effect.
  3. The following seems to contain information which should be mentioned elsewhere in the article:
    Some light guns do not work with this type of display since they do not have flexible lighting dynamics that CRTs have. However, the field emission display will be a potential replacement for LCD flat-panel displays since they emulate CRTs in some technological ways.

--Whiteknox 17:37, 10 August 2006 (UTC)

"Sometimes the panel can be restored to normal by displaying an all-white pattern for extended periods of time." Is this true? If so, does this apply to all panel types? mmj 11:48, 15 August 2006 (UTC)

  • "Playing video games on an LCD T.V. isn't recommended due to the controls being delayed, which can sometimes mess the player up in gameplay." is the current last line and is also covered by a higher line mentions screen lag , or delay time . PidGin128 from 149.168.174.18 19:07, 18 October 2007 (UTC)
It's been deleted. If it's verifiable, bring it back with a source; be sure to say who recommends against LCD here. Dicklyon 20:32, 18 October 2007 (UTC)
  • I think the "Some LCD monitors can cause migraines and eyestrain problems due to flicker from fluorescent backlights fed at 50 or 60 Hz." drawback should be deleted. I mean - this drawback is not exclusive to LCD displays. CRT displays flicker even more. Another thing: why is the article about LCD displays the only one that has a separate section for drawbacks? Fanboys defending CRT displays? --Lim-Dul (talk) 19:49, 23 December 2007 (UTC)
WP:SOFIXIT. I fixed it for you, by taking it out. Anything that's questionable and unsourced can be simply removed; if someone thinks it's real, they'll bring it back with a source. As to why other articles don't have such a section, maybe you should there, or just start some; but be sure to use only sourced drawbacks. Dicklyon (talk) 19:57, 23 December 2007 (UTC)
what about advantages? there's no advantages section--Esteban.barahona (talk) 20:55, 21 January 2008 (UTC)

[edit] Crystal Liquids 'R' Us

someone fix the vandalism 85.228.212.107 02:30, 26 August 2006 (UTC)

[edit] LCD Display

Isn't it redundant to say LCD Display. It's stated at such several times in the article but I don't feel wiki-wise enough to decide a correction yet.

Yes it is. But it's pretty conventional, as you can see here. Dicklyon 21:58, 18 November 2006 (UTC)
It is not only redundant, it is stupid and wrong! The more such wrong expressions are repeated by WikiPedia the more they seem to become "conventional" ... In the LCD community we usually use "LC-display" or just LCD.

Any correction is supported by me.

panjasan 16:44, 25 March 2007 (UTC)panjasan

[edit] Vandalism

What is going on with this page? Both 203.131.165.194 and 66.242.230.91 have apparently vandalized this page just recently. --Whiteknox 22:17, 5 December 2006 (UTC)

[edit] There should be a mention of raw pixel counts

Makers of non computer LCD displays often quote the raw pixel count (color sub pixels) of a color display, or will quote the raw pixels (color sub pixels) per line in a display.

example: A 640 x 480 display that upscales to 1024 x 768 would instead be advertised as a 921600 pixel display, instead of listing the native resolution, or a display may be advertised as being 1920(H)pixels x 480(V)pixels.

The math for this obfuscation is simple, they simply add all three of the color sub pixels into the pixel count, so 640 x 480 becomes 640 x 3 x 480 = 921600.

Here's a quick table of common resolutions, and their raw or sub pixel counts.

Name Resolution "Raw" Pixels
QVGA 320×240 230400 pixels
HVGA 480×320 460800 pixels
VGA 640×480 921600 pixels
SVGA 800×600 1440000 pixels
XGA 1024×768 2359296 pixels
XGA+ 1152×864 2985984 pixels
SXGA 1280×1024 3932160 pixels
SXGA+ 1400×1050 4410000 pixels
UXGA 1600×1200 5760000 pixels

Oujdeivß 12:24, 19 December 2006 (UTC)

Is it "non-computer" that defines the market where they count this way? Seems like a bad idea, based on how much confusion is caused in cameras by counting each single-color detector as a pixel, but there we're stuck with it. Do you have references to sources that do it this way? Dicklyon 19:10, 2 January 2007 (UTC)
A pixel (= picture element) in the displays field is the smallest group of elements that can reproduce the full range of colors. In RGB displays a pixel comprises three sub-pixels of the primary colors red, gree and blue. See: ISO-13406 (Ergonomic requirements for work with visual displays based on flat panels — Part 2: Ergonomic requirements for flat panel displays), Definition 3.4.7: pixel: smallest element that is capable of generating the full functionality of the display. panjasan 17:00, 25 March 2007 (UTC)panjasan

[edit] Pixel counts & resolution

For Oujdeivß, you should check this page : http://en.wikipedia.org/wiki/Display_resolution


and maybe this link should be added in the "See also" section of the article

[edit] Skin tones???

IT IS ENTIRELY RACIST TO SUGGEST THAT LCDS CAUSE PROBLEMS FOR "SKIN TONES". IN REALITY THEY ONLY CAUSE AN ISSUE FOR THE LIGHT SKIN CHARACTERISTIC OF MANY EUROPEAN ETHNICITIES. PLEASE REMOVE THIS. 81.192.141.90 16:55, 10 January 2007 (UTC)

Calm down. Discussing "skin tones" is not racism. 154.20.137.51 04:53, 9 April 2007 (UTC)

Yeah. At worst it's careless and misleading. At best, it's just an acknowledgement that those European skin tones exist, and matter. Bryan Henderson 20:30, 29 September 2007 (UTC)

[edit] Power Consumption

I think it would be very interestiingh to know what the power consumption of LCD displays are in comparison to other types of displays, and also now that I think of it there really should be a single page that makes a comparison of the wattage used by regular household appliances.``193.203.136.214 01:38, 28 January 2007 (UTC)

Yes, I had assumed they do not use as much power as CRT monitors? And if they use significantly less, then it should definitely be pointed out.


[edit] Article with unsourced statements since February 2007

How can the "unsourced statements" in this article be found ? panjasan 16:53, 25 March 2007 (UTC)panjasan

[edit] Prized by engineers??

I'm an engineer and I don't prize LCD screens. Engineers prize a full range of utilities not just power use. I prize my cathode ray tube tv because the colour is perfect from any viewing angle and it was cheap. Engineers have any number of variables to consider in design, so for one application an LCD will be useless and for another it will be useful. Can anyone tell me why, if power consumption is the only important variable in a screen, that cathode ray tubes tvs are still being designed? I reckon the "prized" part should be removed, engineers have opinions specific to the application and limiting factors they design for. 193.1.172.104 17:32, 23 April 2007 (UTC)

I think "prized" is an awful choice of word here. That statement doesn't belong on an encyclopedia. -TCB

[edit] This section is (pardon me) crap

Active matrix technologies

Main article: TFT LCD, Active-matrix liquid crystal display

Twisted nematic (TN)

Twisted nematic displays contain liquid crystal elements which twist and untwist at varying degrees to allow light to pass through. When no voltage is applied to a TN liquid crystal cell, the light is polarized to pass through the cell. In proportion to the voltage applied, the LC cells twist up to 90 degrees changing the polarization and blocking the light's path. By properly adjusting the level of the voltage almost any grey level or transmission can be achieved..

In-plane switching (IPS)

In-plane switching is an LCD technology which aligns the liquid crystal cells in a horizontal direction.

panjasan: The same is the case for the TN-effect, so what's the actual difference ?

In this method, the electrical field is applied through each end of the crystal,

hmmm, interesting ...

but this requires two transistors for each pixel instead of the one needed for a standard thin-film transistor (TFT) display.

panjasan: wow, this might also be new to the manufacturers of LCDs !

This results in blocking more transmission area requiring brighter backlights, which consume more power making this type of display less desirable for notebook computers.

panjasan: OK, transmission is reduced, but not by the presence of the assumed two transistors per (sub)-pixel.


Please study verified sources before spreading rumors and nonsense here !

panjasan

I found the section to be pretty much incomprehensible. It should build on the foundation of the earlier sections of the article, but seems to assume some other background in how LCDs work.
One part that's hard to take: "In this method, the electrical field is applied through each end of the crystal." How is it applied in other methods? There's only one way to apply an electrical field: with electrodes on either end of the field.
But it's not just this section. The one before doesn't tell what the transistor is for, and seems to say that row/column addressing is unique to active matrix. And it alludes to some kind of refresh not otherwise described. (The hyperlink for "refresh" leads to an article whose only mention of LCDs is to say it is inapplicable to LCDs). It fails to state the difference between passive matrix and active matrix, referring to presence or absence of a "steady charge" which is never described.
Bryan Henderson 20:45, 29 September 2007 (UTC)

[edit] viewing angle

I noticed that the LCD technology used for television displays had improved greatly of late and problems with viewing angle have been practically eliminated in affordable displays. I was hoping to find in this article an explanation of the technology used to achive this. If anyone knows, could you please add it in, for example to the history section. Thanks. 69.232.68.142 10:51, 17 June 2007 (UTC) Sandy

When a voltage is applied across the electrodes, a torque acts to align the liquid crystal molecules parallel to the electric field, distorting the helical structure (this is resisted by elastic forces since the molecules are constrained at the surfaces).

If the liquid crystal is constrained on the surfaces, then while it may twist in the interior, the front face orientation is equivalent to the back face orientation. This omits the possibility of perpendicular orientation. While I know this is not what the author meant, I feel that this is not clear.

[edit] Commercial success

When did LCD displays become commercially successful? -- Beland 17:34, 1 August 2007 (UTC)

[edit] Front blurring filter?

I have sufficiently good eyesight that I would expect to be able to discern the subpixels; however I see each pixel as a uniform colour (mainly white, in the case of this page). If I look at the pixels with a macro lens (600mm) which has a very narrow depth of field, then it has the same effect as a microscope, permitting me to focus at different depths within the display. At one depth, the coloured subpixels are clearly apparent; however when looking near the surface, the subpixels cannot be seen (although the screen-door effect is still sharply in focus).

I conclude that:

  • There is some surface coating on each pixel, which blurs the 3 subpixels into a uniformly illuminated pixel. [This is beneficial behaviour, in the same way that a projection screen should be operated very fractionally out-of-focus, to avoid the screen-door effect]
  • Sub-pixel antialising is fairly pointless, and causes substantial colour-fringing, without really improving smoothness.

Can someone knowledgeable confirm this? RichardNeill 03:48, 15 September 2007 (UTC)

This is not the case. The human eye cannot detect the subpixels and will converge the colors together. An examination of the pixel/sub-pixel under magnification will prove this. —Preceding unsigned comment added by 68.178.76.74 (talk) 21:09, 10 March 2008 (UTC)

[edit] Quality control

Why, in this section, am I barraged with information about Integrated circuits? I understand drawing a small analogy at the start to show how QA/QC in LCDs relates to other industry. This, however, seems to me like the entire section is meant to be a comparison between the two. As a casual reader, I wanted to scream out, "I don't care!" I just wanted to learn about LCDs. Never mind that, this is the first time that IC is mentioned in the entire article. So the non-technical reader is left wondering "what the heck is an IC, why do I care, and what does any of that have to do with LCDs?"

My suggestion: present relevant information about LCDs. Ditch the rest. Endasil 20:22, 1 October 2007 (UTC)

WP:SOFIXIT. Dicklyon 06:30, 2 October 2007 (UTC)

Yeah, thanks for that Dick. But I actually know nothing about the technology. I was seriously asking, why is this section the way it is. I was looking for an opinion from other users. If there is a reason to compare the two, then fine, lets change it to clarify that reason. But I'm not going to tear apart a section on my own opinion with no feedback, thanks. Endasil 02:13, 3 October 2007 (UTC)

[edit] Self-reference

Although the photo of the Wikipedia logo on the LCD display is very well-done, it's both an unnecessary self-reference (Wikipedia:Avoid self-reference) and may run up against copyright issues, since the logo is not available under a free license. I suggest replacing it with another image based on a public domain source image. Dcoetzee 19:31, 16 November 2007 (UTC)

I have since done exactly this. Hope the replacement picture is sufficient.
Vanessaezekowitz (talk) 10:20, 23 January 2008 (UTC)

[edit] Overview Each pixel of an LCD typically consists of a layer of molecules aligned between two transparent electrodes, and two polarizing filters, the axes of transmission of which are (in most of the cases) perpendicular to each other. With no liquid crystal between the polarizing filters, light passing through the first filter would be blocked by the second (crossed) polarizer.

The surface of the electrodes that are in contact with the liquid crystal material are treated so as to align the liquid crystal molecules in a particular direction. This treatment typically consists of a thin polymer layer that is unidirectionally rubbed using, for example, a cloth. The direction of the liquid crystal alignment is then defined by the direction of rubbing.

Before applying an electric field, the orientation of the liquid crystal molecules is determined by the alignment at the surfaces. In a twisted nematic device (still the most common liquid crystal device), the surface alignment directions at the two electrodes are perpendicular to each other, and so the molecules arrange themselves in a helical structure, or twist. Because the liquid crystal material is birefringent, light passing through one polarizing filter is rotated by the liquid crystal helix as it passes through the liquid crystal layer, allowing it to pass through the second polarized filter. Half of the incident light is absorbed by the first polarizing filter, but otherwise the entire assembly is transparent.

When a voltage is applied across the electrodes, a torque acts to align the liquid crystal molecules parallel to the electric field, distorting the helical structure (this is resisted by elastic forces since the molecules are constrained at the surfaces). This reduces the rotation of the polarization of the incident light, and the device appears gray. If the applied voltage is large enough, the liquid crystal molecules in the center of the layer are almost completely untwisted and the polarization of the incident light is not rotated as it passes through the liquid crystal layer. This light will then be mainly polarized perpendicular to the second filter, and thus be blocked and the pixel will appear black. By controlling the voltage applied across the liquid crystal layer in each pixel, light can be allowed to pass through in varying amounts thus constituting different levels of gray.


LCD alarm clockThe optical effect of a twisted nematic device in the voltage-on state is far less dependent on variations in the device thickness than that in the voltage-off state. Because of this, these devices are usually operated between crossed polarizers such that they appear bright with no voltage (the eye is much more sensitive to variations in the dark state than the bright state). These devices can also be operated between parallel polarizers, in which case the bright and dark states are reversed. The voltage-off dark state in this configuration appears blotchy, however, because of small variations of thickness across the device.

Both the liquid crystal material and the alignment layer material contain ionic compounds. If an electric field of one particular polarity is applied for a long period of time, this ionic material is attracted to the surfaces and degrades the device performance. This is avoided either by applying an alternating current or by reversing the polarity of the electric field as the device is addressed (the response of the liquid crystal layer is identical, regardless of the polarity of the applied field).

When a large number of pixels is needed in a display, it is not technically possible to drive each directly since then each pixel would require independent electrodes. Instead, the display is multiplexed. In a multiplexed display, electrodes on one side of the display are grouped and wired together (typically in columns), and each group gets its own voltage source. On the other side, the electrodes are also grouped (typically in rows), with each group getting a voltage sink. The groups are designed so each pixel has a unique, unshared combination of source and sink. The electronics, or the software driving the electronics then turns on sinks in sequence, and drives sources for the pixels of each sink.


[edit] Specifications Important factors to consider when evaluating an LCD monitor:

Resolution: The horizontal and vertical size expressed in pixels (e.g., 1024x768). Unlike CRT monitors, LCD monitors have a native-supported resolution for best display effect. Dot pitch: The distance between the centers of two adjacent pixels. The smaller the dot pitch size, the less granularity is present, resulting in a sharper image. Dot pitch may be the same both vertically and horizontally, or different (less common). Viewable size: The size of an LCD panel measured on the diagonal (more specifically known as active display area). Response time: The minimum time necessary to change a pixel's color or brightness. Response time is also divided into rise and fall time. For LCD Monitors, this is measured in btb (black to black) or gtg (gray to gray). These different types of measurements make comparison difficult. Refresh rate: The number of times per second in which the monitor draws the data it is being given. A refresh rate that is too low can cause flickering and will be more noticeable on larger monitors. Many high-end LCD televisions now have a 120 Hz refresh rate (current and former NTSC countries only). This allows for less distortion when movies filmed at 24 frames per second (fps) are viewed due to the elimination of telecine (3:2 pulldown). The rate of 120 was chosen as the least common multiple of 24 fps (cinema) and 30 fps (TV). Matrix type: Active or Passive. Viewing angle: (coll., more specifically known as viewing direction). Color support: How many types of colors are supported (coll., more specifically known as color gamut). Brightness: The amount of light emitted from the display (coll., more specifically known as luminance). Contrast ratio: The ratio of the intensity of the brightest bright to the darkest dark. Aspect ratio: The ratio of the width to the height (for example, 4:3, 16:9 or 16:10). Input ports (e.g., DVI, VGA, LVDS, or even S-Video and HDMI). —Preceding unsigned comment added by 87.236.233.66 (talk) 07:50, 20 February 2008 (UTC)

[edit] Flickering

From article : "A refresh rate that is too low can cause flickering ..."

This should be clarified that LCD do not flicker. By design. Plasma, CRT and some other flicker. --Xerces8 (talk) 14:00, 22 February 2008 (UTC)

LCDs can flicker, in a light tube used as a backlight is damaged. Or something in the construction is wrong :) Ceridan (talk) 15:21, 13 May 2008 (UTC)

[edit] Viewing angle information misleading

The article says (under Drawbacks) : "typically the color only gets a little brighter when viewing at extreme angles."

Modern (as of 2008) (S-)PVA monitors have the "color only gets a little brighter" effect even at small viewing angles, like 20 degrees. I witnessed this on my (Hyundai W241D) monitor and some others (Samsung 204Ts and HP LP2465). This forum post also mentions that this is so on all PVA and MVA panels. --Xerces8 (talk) 14:50, 11 March 2008 (UTC)

I also think more information shoudl be added, especially about *VA monitors have some annoying features known as "gamma shift" and "black crush". It is because of teh crystal structure and is not avoidable in these panels. As English is not my native language, I'd better leave an enrichement of this article to someone other :)

Ceridan (talk) 15:19, 13 May 2008 (UTC)