Talk:Liquid-crystal display

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)

"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.

"smooth"? 87.112.222.13 (talk) 19:10, 15 November 2010 (UTC)

"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)

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

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

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)

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

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

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

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

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)

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)/

While it is useful, links to the relevant pages on wikihow or ehow would probably be more applicable. 87.112.222.13 (talk) 19:12, 15 November 2010 (UTC)

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)

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

 * PC World May 23, 2006 p. 43
 * 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)

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)

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 &bull; talk 08:53, 18 June 2006 (UTC)

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)

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 ">".


 * 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

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

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/

Drawbacks and advantages
"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."
 * 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?
 * 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)
 * I think it is likely that what you observed was due not to response time but to the fact that an LCD pixel is constantly lit for the duration of the frame (16.7ms), whereas a CRT pixel is lit for only a fraction of a microsecond once during a frame. This means that even with an absolute zero response time, a panning image on an LCD panel will appear blurred while it may appear smooth on a CRT (if the image itself has no motion blur).  The additional blurring in the case of LCD comes from the movement of our eyes; it doesn't happen on CRT because our eyes do not move enough during the nanoseconds that a pixel remains lit.   Ghosting caused by a slow response rate would be not only blurring, but also a constant 'double image' - seeing two or more recent frames, or ghosts from them, simultaneously.  This would be in addition to the motion blur.  mmj (talk) 04:41, 8 January 2009 (UTC)

--Whiteknox 17:37, 10 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.
 * 1) 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.

"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)


 * I've removed the claims of higher resolutions from CRTs. The example provided was of a 19" CRT being able to do 2048x1536. While you may be able to feed a 2048x1536 analog signal to a CRT, they simply don't have enough phosphor dots to show that many pixels. For example, a 21" SGI GDM-5411 CRT monitor has a viewable area of 403.8x302.2mm, and a 0.24mm aperture grille pitch, giving a native resolution of about 1682x1259. Glenn Anderson (talk) 07:27, 26 January 2009 (UTC)

Crystal Liquids 'R' Us
someone fix the vandalism 85.228.212.107 02:30, 26 August 2006 (UTC)

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

It is hardly fair to justify the usage of LCD display by comparing the results of LC-display with LCD-display, since the most likely alternative (or at least, very notable alternative) is simply "LCD", in which case LCD (AND LC-display) [correct usages] would easily outnumber LCD-display [incorrect usage]. Of course there is the issue of LCD itself including results of LCD display, but I AM trying to establish that google fight is not relevant, even for discussions of usage and popularity.

I am extremely disappointed with Wikipedia. I am all for the colloquial development of language, but mostly in the sense of CHANGING definitions. This is simply a mistake. Worst of all is the reasoning -- a lot of people make the mistake, so it is OK for us to do it. Frankly, "a lot of people" are not encyclopedias. Wikipedia, on the other hand, (ideally) is.

It is mistakes like this, not vandalism, that plagues Wikipedia's reputation. 99.255.52.77 (talk) 03:49, 29 October 2009 (UTC)

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)

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. 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

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

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)

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.

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

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

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)

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.

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

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)

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)

Self-reference
Although the photo of the Wikipedia logo on the LCD display is very well-done, it's both an unnecessary self-reference (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)

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)

Low input refresh rates should not cause flicker in an LCD screen though, as the controller in the screen holds frames and re-displays them until a new frame is available (source is a physicist friend who was involved in OLED screens, I imagine there'll be some relevant paper though) 87.112.222.13 (talk) 19:23, 15 November 2010 (UTC)

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)

Color displays

A subpixel of a color LCD Simulation of an LCD monitor up close Comparison of the OLPC XO-1 display (left) with a typical color LCD. The images show 1×1 mm of each screen. A typical LCD addresses groups of 3 locations as pixels. The XO-1 display addresses each location as a separate pixel.In color LCDs each individual pixel is divided into three cells, or subpixels, which are colored red, green, and blue, respectively, by additional filters (pigment filters, dye filters and metal oxide filters). Each subpixel can be controlled independently to yield thousands or millions of possible colors for each pixel. CRT monitors employ a similar 'subpixel' structures via phosphors, although the electron beam employed in CRTs do not hit exact 'subpixels'.

Color components may be arrayed in various pixel geometries, depending on the monitor's usage. If software knows which type of geometry is being used in a given LCD, this can be used to increase the apparent resolution of the monitor through subpixel rendering. This technique is especially useful for text anti-aliasing.

To reduce smudging in a moving picture when pixels do not respond quickly enough to color changes, so-called pixel overdrive may be used.

[edit] Passive-matrix and active-matrix addressed LCDs

A general purpose alphanumeric LCD, with two lines of 16 characters.LCDs with a small number of segments, such as those used in digital watches and pocket calculators, have individual electrical contacts for each segment. An external dedicated circuit supplies an electric charge to control each segment. This display structure is unwieldy for more than a few display elements.

Small monochrome displays such as those found in personal organizers, or older laptop screens have a passive-matrix structure employing super-twisted nematic (STN) or double-layer STN (DSTN) technology—the latter of which addresses a color-shifting problem with the former—and color-STN (CSTN)—wherein color is added by using an internal filter. Each row or column of the display has a single electrical circuit. The pixels are addressed one at a time by row and column addresses. This type of display is called passive-matrix addressed because the pixel must retain its state between refreshes without the benefit of a steady electrical charge. As the number of pixels (and, correspondingly, columns and rows) increases, this type of display becomes less feasible. Very slow response times and poor contrast are typical of passive-matrix addressed LCDs.

High-resolution color displays such as modern LCD computer monitors and televisions use an active matrix structure. A matrix of thin-film transistors (TFTs) is added to the polarizing and color filters. Each pixel has its own dedicated transistor, allowing each column line to access one pixel. When a row line is activated, all of the column lines are connected to a row of pixels and the correct voltage is driven onto all of the column lines. The row line is then deactivated and the next row line is activated. All of the row lines are activated in sequence during a refresh operation. Active-matrix addressed displays look "brighter" and "sharper" than passive-matrix addressed displays of the same size, and generally have quicker response times, producing much better images. —Preceding unsigned comment added by 59.93.19.185 (talk) 07:16, 5 July 2008 (UTC)

Electro-optical amplitude modulator
The lead says that an LCD is an electro-optical amplitude modulator. Is it not an electrically modulated optical amplification device (subtly different), being controlled by an electro-optical amplitude modulator ? Electro-optic modulator (which is linked to electro-optical amplitude modulator on the article) says that the modulator may be applied in four areas including phase, frequency and amplitude which may affect the display prior to visibility but could an LCD display, without processing any picture just monochrome light, be switched and display light without an electro-optical amplitude modulator (hence not actually being one just completely dependant on it)? ~ R . T . G  08:06, 23 December 2008 (UTC)
 * An LCD modulates amplitude only of a separate light source. It amplifies nothing. Cuddlyable3 (talk) 14:36, 23 June 2009 (UTC)

Advanced Fringe Field Switching (AFFS)
This section is a press release, from the sound of it. —Preceding unsigned comment added by 24.215.187.165 (talk) 16:49, 12 March 2009 (UTC)

Note
T. Peter Brody did not create the first fully functional LCD, it was Scott H. Holmberg. —Preceding unsigned comment added by 98.246.71.85 (talk) 23:43, 17 March 2009 (UTC)

Does their Refresh happen from top to bottom like CRTs or all at the same time?
Does anyone have a source to it to include it in the article? --AaThinker (talk) 18:55, 3 May 2009 (UTC)

LCDs do not refresh the screen from top to bottom; every pixel is refreshed simultaneously. —Preceding unsigned comment added by 208.101.129.212 (talk) 06:40, 12 November 2009 (UTC)

Have a look into "screen tearing". The full image is refreshed very quickly (compared to CRTs), but it is scanned. 87.112.222.13 (talk) 19:26, 15 November 2010 (UTC)

Mother glass
Nothing on Mother glass in this entire article? --68.45.218.70 (talk) 17:02, 3 June 2009 (UTC)

Optical-sensor LCD
Does this new technology belong in this article? It seems like a relevant new technology in the multi-touch applications arena. Perhaps even security in the future. Or perhaps it should have it's own article? I'm not incredibly familiar with the technology and it's penetration but Sharp recently introduced a laptop with it as a track pad. Rasmasyean (talk) 06:31, 8 June 2009 (UTC)

Reference desk/Science
Hi, these remarks have not been answered for a while, so, when putting a remark about the technology or the inventors etc. go to the Science Reference Desk where you will surely get lots of responses from people who know lots of stuff like this. ~ R . T . G  23:44, 22 June 2009 (UTC)

Pixelation
Can someone write something about LCD TV's having pixelated image problems. —Preceding unsigned comment added by Ericg33 (talk • contribs) 04:45, 20 July 2009 (UTC)

Article issues
This article is probably very  important. I happened on it by  chance while editing  a page on  an entirely  different  subject  that  links to  it. I read the page with interest  but  felt I had to  point  out some critical  MoS flaws in  its presentation. I have carried out some minor copy editing, but as electronics is not my  field, I  am  unable to address the other points I  have flagged. The article has been written in good faith by knowledgeable contributors, and contains a wealth  of information. However, its overall tone may  need to be improved for presentation  in  encyclopedic style. Some sections and parts of the text have been tagged for a long time as being  in  need of attention, and I  have added some others. This is in no way intended as a criticism, and should be regarded as flagging of areas that may need attention. However, critical unreferenced statements or sections can be deleted by anyone at any time. Its rating at  'B' class may require reconsideration as a 'C' class exists which  would probably relate more accurately the the articl's current  standard. See some possible suggestions below for improvement of the sections: The article appears to be biased towards the use of LCDs as computer monitors. This may well  be the most  widespread use, but  more balance is possibly required.
 * Overview: unnecessarily technical and focussed on manufacture. Consider  renaming  the section and/or shortening  and incorporating  elements into  other relevant sections
 * Brief History: This not really brief. Renaming  as 'History'  would be sufficient,  otherwise this could imply that  the article is incomplete due to  lack of time on the part  of the author. Should be the next  section. Consider using  prose, rather than  a bulleted list. If the article can be expanded, consider splitting  in to  a new article: History  of LCD displays
 * Specification: Wiki is not  an instruction  manual. This section should ideally  come towards the end of the article.
 * Manufacturers: It may be preferable to  either display  this in  'flatlist' format', or to create a new list-article.
 * Quality control: This section  may  be too long  and/or too  detailed for an encyclopedic article, and may  read like an article from  a technical article.
 * Drawbacks: Consider using prose, rather than  a bulleted list. Note:this detailed section  on  drawbacks puts a negative slant  on  LCDs that  is not adquately  compensated for neytrality  in  the other parts of the article.
 * External links: There may be too many which confuses the reader with a vast variety  of optional sources. Wiki  is not a link farm.
 * General information: There may be too  many which confuses the reader with a vast variety  of optional sources. Wiki  is not a link  farm.
 * Many links (inline, references, external, general information) need to  be tweaked to  display  accordsing  to  MoS. --Kudpung (talk) 05:10, 22 July 2009 (UTC)

Requested move

 * Not Moved. (See Talk:High-definition television for similar discussion.) Station1 (talk) 06:07, 16 October 2009 (UTC)

Liquid crystal display → LCD — Per WP:ABBR: Acronyms should be used in page naming if the subject is almost exclusively known only by its acronym and is widely known and used in that form (e.g., NASA and radar). User:GraYoshi2x 02:05, 8 October 2009 (UTC)


 * Oppose. "LCD" is not an acronym (it contains no vowel and cannot be pronounced), unlike "NASA" or "radar"/"laser".  No-one ever says "National Aeronautics and Space Administration" or "Light emission by stimulated emission of radiation", so those would be implausible search terms.  "LCD" redirects to this article (despite its alternative meanings), so what's the problem? Sussexonian (talk) 07:37, 8 October 2009 (UTC)
 * Brush up on your definitions and keep in mind Wikipedia is not a vote. Acronyms don't have to be pronounceable and I have rarely heard LCD refer to anything other than this article. And if you oppose it, just say it directly, please.  GraYoshi2x► talk 19:28, 8 October 2009 (UTC)
 * I have edited my 'No, thank you' above to 'Oppose'. An acronym is a word made from initial letters and NASA, NATO, radar and laser are examples.  LCD and others are abbreviations not acronyms (I accept that the two are sometimes used interchangeably).  The policy is WP:ABBR not WP:ACRO and the writer clearly understood the difference.  The examples quoted (NASA, radar) have the specific features that (i) they are pronounceable and (ii) they are hardly ever spoken as complete phrases.  'Patriot Act' is another example where Wikipedia's article is named for the abbreviation.  'FBI' and 'CIA' are not: they are phrases spoken as abbreviations/initialisms and their full forms are well known.  Sussexonian (talk) 07:57, 9 October 2009 (UTC)
 * You've completely ignored me when I said to look up the definitions. Acronyms do not have to be pronounceable, simple as that. Stop insisting they must be. Even all the major dictionaries agree that FBI can be considered as an acronym.  GraYoshi2x► talk 20:17, 9 October 2009 (UTC)
 * I may go and look at some dictionaries, but there is a distinction made in the policy, between acronym and abbreviation, the examples in the policy comply with the restricted definition of acronym, and FBI is not a Wikipedia article name. On the other page you have said CIA/FBI are more well known by their abbreviations: that is exactly my point, as with LCD the more common identifier is the short form but Wikipedia has not chosen to rename Federal Bureau of Investigation.  So the actual practice on Wikipedia seems to me to coincide with my interpretation.  Sussexonian (talk) 22:25, 9 October 2009 (UTC)
 * WP:OTHERSTUFFEXISTS  GraYoshi2x► talk 23:44, 9 October 2009 (UTC)


 * Oppose per Sussexonian. Irrespective of the difference between an acronym and an abbreviation (we have DHL rather than Dalsey, Hillblom and Lynn, after all), I would emphasisse "almost exclusively known only by its acronym".  "Liquid crystal display" is a perfectly ordinary everyday expression. Tevildo (talk) 00:43, 10 October 2009 (UTC)
 * Look at NASA then. There are quite a few people who say the entire phrase, but simply not enough to justify making it the main titling. Same goes with HDMI.  GraYoshi2x► talk 20:41, 10 October 2009 (UTC)


 * Oppose. In the case of NASA, the acronym gets 127 million hits on Google, the full name only 5,000. In the case of LCD, the full name gets millions of hits on Google. 199.125.109.19 (talk) 14:03, 11 October 2009 (UTC)
 * Oppose. Normally Wikipedia articles should have a long name and the acronym should redirect to it; it requires strong evidence of "known by acronym only" before moving in that direction. Even IEEE has its article as the full name. --Alvestrand (talk) 16:51, 11 October 2009 (UTC)

The term Liquid crystal. Is there any problem in very cold temp of freezing the liquid. Or is that a stupid question? —Preceding unsigned comment added by 65.190.161.35 (talk) 20:55, 7 January 2010 (UTC)

Videogames?
The shocking lack of mention of handheld videogames and their importance in driving improvement of LCD technology is appalling.66.159.224.65 (talk) 20:38, 19 January 2010 (UTC)


 * I completely agree, the entire reason I came to this page at all was to learn more about the Game & Watch type systems. And I find it particularly insulting that the Brief history section goes directly from 1972 to 1998, one could claim the peak years of LCD advancement, all taking place in handheld game consoles. Zak Frost (talk) 13:18, 31 May 2010 (UTC)

Instead of feeling shocked and appalled, how about contributing something useful? On second thought, never mind. &mdash; QuicksilverT @ 14:10, 27 October 2011 (UTC)

Dubious assertion
"Many LCDs are incapable of displaying very low resolution screen modes (such as 320x200) due to these scaling limitations." Can anyone cite anything to back this up? I don't see any reason why scaling from 320x200 to whatever the panels native resoloution is would be any harder than scaling from (say) 640x480 to the panels native resoloution. 86.1.116.158 (talk) 19:12, 27 January 2010 (UTC)

It may be more accurate to say that some LCD display units suffer from this limitation, as different display devices are made differently. It depends on who is making the display unit, as to what ability they allow it to have. Some actually allow you to turn off scaling alltogether, but still do not allow "non-standard" resolutions or "small" resolutions. —Preceding unsigned comment added by 216.231.159.16 (talk) 20:21, 20 February 2010 (UTC)

Manufacturers
I feel there needs to be a distiction made in this section as to which companies actually construct LCD Panels and which companies order LCD Panels from other manufacturers and simply assembly the components into a TV.

The only LCD Panels Manufacturers I know of are Philips and LG. Currently all the companies listed are strictly LCD TV or LCD Display manufacturers, they purchase LCD Panels from either Philips or LG and then assemble the displays. —Preceding unsigned comment added by 98.225.216.197 (talk) 13:22, 2 March 2010 (UTC)

Are 'Zero-power LCD' a category of electronic paper?
Hope I'm doing this right - I'm not that experienced in asking questions on articles on Wikipedia.

Under the headline “Zero-power (bistable) displays” someone has written:

"Zero-power LCDs are a category of electronic paper."

But I don’t think this is correct, if I look at the definition of e-paper

Electronic paper, e-paper or electronic ink display is a display technology designed to mimic the appearance of ordinary ink on paper (from http://en.wikipedia.org/wiki/Electronic_paper)

I’ve seen zero-powered, bistable LCD with my own eyes, and the one I saw looked just like ordinary LCD which, as you know, don’t have the appearance of ink on paper: The characters sort of ‘hovers’ in the display, unlike the characters on, say, the Kindle’s display.

So, is this something I can/should correct in this article or is it the definition of e-paper that needs adjusting? RipRapRob (talk) 10:12, 17 March 2010 (UTC)


 * I've deleted the "Zero-power LCDs are a category of electronic paper." sentence. RipRapRob (talk) 16:58, 5 April 2010 (UTC)

Color gamut is not color support
suggested text
 * 1) [Chromatic resolution]: How many colors are supported. This may be expressed in several ways such as total number of colors (e.g. "8 million"), as color resolution per color channel (e.g. "8 bit color" which is the color resolution for each of the color channels; usually red green and blue) or as total color resolution (e.g. "24 bit color"; which is the same as 8 bit color, just multiplied by the three channels).
 * 2) [Color gamut]: The range of colors that can be displayed; usually expressed as conforming to some standard such as the 1957 NTSC standard. Color gamut differs from color resolution in that color gamut expresses the total range of colors while color resolution indicates how many individual colors that range is divided into. An LCD can have a wide color gamut but still have weak color performance if the resolution is inadequate. Inadequate resolution will result in distinct color bands in an image where the colors are supposed to change continuously. This is termed "Posterization". Posterization used to be common but most LCD makers have moved to 36 bit color and beyond which is well beyond the chromatic resolution capability of humans.  —Preceding unsigned comment added by Norman Hairston (talk • contribs) 20:08, 8 May 2010 (UTC)

The active matrix LCD
I changed the portion on the invention of the active matrix LCD. While Peter Brody will tell you that he invented it(and he certainly did a lot to promote it), the active matrix LCD was invented in a lab that reported to Peter, not by Peter himself. His name is not on the patent.

Also, though I did not include it, two major events in the development of the LCD were the exit of Westinghouse from the TV business and the purchase of RCA by GE. Both events had a stiffing effect on display technology innovation that persists to this day. Peter Brody's claim of ownership for the active matrix LCD further submerges the impact of innovative organizations on development of display technology. —Preceding unsigned comment added by 216.102.41.194 (talk) 14:58, 11 May 2010 (UTC)

I tagged this article
I tagged this article with the multiple issues I saw, and I am in NO WAY someone who can usually tag soemthing, I don't have alot of experience, but this article is HIDEOUS! anyways, thought I'd mention something =) --Cayden Ryan (talk) 18:19, 21 May 2010 (UTC)

Double refractive index
Most Liquid Crystals have Double Refraction. There was no mentioning in this article. Can someone find a source for that? Suki300me (talk) 04:13, 14 June 2010 (UTC)

You're probably referring to birefringence, an angle-dependent refractive index due to anisotropy in the long-range ordering of molecules in the material. Have a look at "birefringence", "calcite" or BBO/KTP/DTP crystals. Birefringence (whilst important to LCDs) belongs in this article about as much as "covalent bonding" belongs in "internal combustion engine". 81.152.94.198 (talk) 16:35, 4 January 2011 (UTC)

Mistaken information
There was a section in here discussing upscaling lag. This is a problem of high-definition TVs and not of LCD panels (as the section seemed to imply). I thusly removed it. 208.101.135.65 (talk) 06:47, 16 July 2010 (UTC)

Memory LCD
I suggest include more info about memory LCD.--Hamiltha (talk) 05:30, 20 July 2010 (UTC)

Violet LCD
I have seen advertisements for LCD televisions with yellow but I have yet to hear about violet. Is it possible to manufacture violet LCD technology? LCD televisions with Red, Yellow, Green, Blue, and Violet would be very useful. -- Azemocram (talk) 22:12, 2 August 2010 (UTC)

Considering the human eye responds to bands of red, green and blue, other pixel colours seem more like a marketing gimmick - yellow just stimulates the green and red receptors, in the same way that green and red would. —Preceding unsigned comment added by 87.112.222.13 (talk) 19:30, 15 November 2010 (UTC)

Bazinga
See also: Bazinga

Why do we need to see this also? This disambiguated to only Sheldon Cooper, which is irrelevant to this page, no? TomChunata (talk) 20:21, 19 October 2010 (UTC)

Protect the article?
Might I suggest protecting this article, as half of it seems to be gamer/hd-enthusiast marketing myths? 87.112.222.13 (talk) 19:35, 15 November 2010 (UTC)

Agreed, there's plenty of relevant, accurate (but unsourced) info there, and it will soon be buried amongst unsourced HD/gamer myths if the article is left as a free-for-all. 81.152.94.198 (talk) 16:37, 4 January 2011 (UTC)

Why no pros/cons section? And why all the comparisons with CRT and not plasma?
After reading the article on Plasma Displays, which has an advantages/disadvantages section that lists pros and cons of plasma displays, I'm wondering why the LCD article doesn't have the same kind of thing? If people are researching about LCD TV's, there's a good chance they'd want to know the pros and cons.

One more thing: Why does the introductory section of this article only compare LCDs to the outdated CRTs? It's nice to know that LCDs CDs "...are more energy efficient and offer safer disposal than CRTs," but how do LCDs compare to plasma screens in these two aspects? CRTs are outdated, and while they were the precursor to LCD and Plasma screens, and it is good to know how LCDs compare with the CRTs they replaced, anyone shopping for a new TV will only care how LCDs compare to plasma screens.

--BigOilersFan (talk) 01:40, 20 January 2011 (UTC)

Misleading
The introduction of the article feels like a marketing add for LCD monitors. I wish not to jump to conclusions, but telling half the truth is still lying. I advice for a section describing the problems of LCD monitors. The introduction and comparison with CRT should be more balanced as well. Some of the problems of LCD monitors when compared to CRT include:

(1)Ghosting and motion blur (2)Low color fidelity (3)Fixed resolution (low quality when using resolutions other the native resolution) (4)Less durability (e.g, defective pixel) (5)Problems viewing at an angle.

On the other hand CRT monitors have higher response time, superior color fidelity, true multi-resolution support, and phosphor burn-in is far less common than pixel burnout. Further more with a single defective pixel you need to replace the whole monitor to fix it!).

I am not to here to advertise CRT monitors, neither am I an expert on the subject, but when issues are not mentioned at all and with an introduction like this article's, alarm bells go off. If I am wrong, correct me.--99.246.101.166 (talk) 16:18, 23 January 2011 (UTC)

Gamut vs. content
Article says: "In any case, colour range is rarely discussed as a feature of the display as LCDs are designed to match the colour ranges of the content that they are intended to show. Having a colour range that exceeds the content is a useless feature." This doesn't make much sense to me. What is an example of a gamut expansion that would not have any content worth showing? --Chinasaur (talk) 01:17, 10 February 2011 (UTC)

Ah, I think I understand; it assumes the images to be displayed have been color balanced to a reduced gamut, which is a good assumption generally for the time being. Perhaps could be clarified in the article. --Chinasaur (talk) 09:11, 10 February 2011 (UTC)

3DS Display
I presume this article is going to have a field day at some point discussing the technology behind the 3DS screen once that technology becomes more commonplace -- or at least when the 3DS itself is released. Unless there's already a different article dedicated to glasses-free 3D LCD screens. ProjectPlatinum 17:52, 26 February 2011 (UTC)
 * There's some limited mention now at Autostereoscopy; as reliable sources become available, either or both articles could expand, or a new article created. --- Barek (talk • contribs) - 17:58, 26 February 2011 (UTC)

Toxicity
Hi. Should we mention the toxicity of broken LCD screens that are highlighted in many owner's manuals as warnings and also in research studies such as this? Thanks. ~ AH1 (discuss!) 18:57, 19 April 2011 (UTC)

History of passive-matrix adressed STN-LCDs
In "Brief history" a major milestone is missing: STN-LCDs allowed for the first time passive-matrix displays with considerable information content. More than 60 companies have taken licenses from the Swiss company Brown, Boveri & Cie to manufacture and sell STN-LCDs according to the patents mentioned in the proposed new entry. So far the application of STN in the early Nintendo Game Boy is the only reference given [16]. However, early cellular phones and laptops also used this type of display. At that time active-matrix addressed LCDs were not yet ready for mass production.

Proposed addition to "Brief history" : 1983: Researchers at Brown, Boveri & Cie (BBC), Switzerland, invented the super-twisted nematic (STN) structure for passive-matrix addressed LCDs. H. Amstutz et al were listed as inventors in the corresponding patent applications filed in Switzerland on July 7, 1983, and October 28, 1983. Patents were granted in Switzerland CH 665491, Europe EP 0131216 [1], US 4634229 and many more countries. Scientific details were published in [2].

[1] European Patent No. EP 0131216: Amstutz H., Heimgartner D., Kaufmann M., Scheffer T.J., "Fluessigkristallanzeige," Oct. 28, 1987. https://register.epo.org/espacenet/application?number=EP84107507

[2] T.J. Scheffer and J. Nehring,"A new highly multiplexable LCD," Appl.Phys.Lett.,vol. 48, no. 10, pp. 1021-1023, Nov. 1984. — Preceding unsigned comment added by BBCLCD (talk • contribs) 09:48, 6 July 2011 (UTC)

Muliplex of matrix display — apps for passive-matrix addressed LCDs
1) The Overview section includes a link to multiplexed. This link is not helpful in the context of LCDs, as it explains multiplexing of telecommunicaton transmission. Display matrices are typically addressed by selecting row-by-row sequentially, with the corresponding picture information entered through the columns row-by-row. To address a full picture, a scan of all rows is accomplished in a frame. Propose to delete the link to multiplexed and replace it with a more detailed description of matrix-addressing in LCDs.

2) Section on passive- and active-matrix addressing: The present text suggests that active-matrix addressing has replaced passive-matrix addressing entirely. However, due to higher manufacturing costs for TFTs, potential additional defects and higher power consumption due to backlighting of active-matrix displays, passive-matrix displays are still used for less demanding applications with less pixels than TVs and laptops, where lowest power consumption and/or reading in bright sunlight are of importance.

SwissLCD (talk) 13:10, 20 July 2011 (UTC)

Zero-power (bistable) displays
Delete the second paragraph referring to the company Nemoptic. This company has been under receivership http://media-business.biz/category/feed-categories/nemoptic<ref (french: en liquidation judiciaire Oct. 2010). The website www.nematic.com cannot be called up anymore (reference no. 27). If Seiko is continuing with this technology, a new reference is needed. BBCLCD

History of IPS-LCDs
Proposed addition to Brief history:

1990: Under different titles inventors have conceived electrooptical effects as alternatives to twisted nematic field effect LCDs (TN- and STN- LCDs). One approach was to use interdigital electrodes on one glass substrate only to produce an electric field essentially parallel to the glass substrates. To take full advantage of the properties of this In-Plane Switching (IPS) technology further work was needed. After thorough analysis, details of advantageous embodiments were filed in Germany by Guenter Baur et al and patented in various countries >ref> Patent No. US 5576867: G. Baur, W. Fehrenbach, B. Staudacher, F. Windscheid, R. Kiefer, Liquid crystal switching elements having a parallel electric field and beta o which is not 0 or 90 degrees, filed Jan. 9, 1990. . The Fraunhofer Institute in Freiburg, where the inventors worked, assigned these patents to Merck KGaA, Darmstadt, the world's leading supplier of LC substances.

In addition, Hitachi worked out practical details to interconnect the thin-film transistor array in matrix form and to avoid undesirable stray fields in between pixels later-on.

SwissLCD (talk) 16:07, 15 August 2011 (UTC)

Character and Segment LCDs
These is little discussion of "calculator" and segment (often used in instruments and dashboards) displays. As an encyclopedia article this seems like a basic introduction to static vs multiplexed control, etc. In general the article seems too closely tied to minute of current market trends rather than an good introduction to LCDs; what they are, how they work, etc. — Preceding unsigned comment added by 98.125.224.81 (talk) 17:10, 14 February 2012 (UTC)

Macbook Pro
The macbook pro does not use an IPS. Display panel a. Mentioned in the article. It uses a TN panel. — Preceding unsigned comment added by 112.79.40.138 (talk) 02:55, 11 September 2012 (UTC)

Climate change
Jason Mick has reported on Daily Tech that:

''"The compound nitrogen trifluoride (NF3) is a "missing greenhouse gas" that may have an impact 17,000 times as great as carbon dioxide, according to a new study by atmospheric chemist Michael Prather, published in the journal Geophysical Research Letters on June 26.

The compound is used in the production of Liquid Crystal Display (LCD) Panels, in semiconductors, and in synthetic diamonds. According to Prather, the compound was initially missed by the Kyoto Protocol, the international treaty governing response to global warming, due to the fact that it was not widely used at the time."''

Proposed merge with Optical film
an orphaned page with no references that ought to be just a sentence or two in the main article A3BDFAD9EC0B (talk) 23:16, 30 November 2013 (UTC) Removed the incorrect movie stub template on the article page and replaced the movie project on the Talk page with templates for WikiProjects Physics and Technology.SBaker43 (talk) 06:10, 28 January 2015 (UTC)
 * Support Merge Yea looking into the subject further I have determined that it is a part of the Manufacturing of a LCD Display based on the Google Results. What I would love to see happen in this merge is to add this one line and make it a part of a new section on Manufacturing these things which the article currently lacks. Otherwise I feel this merger will be in vain. Sawblade5 (talk to me undefined my wiki life) 15:50, 2 February 2014 (UTC)
 * Oppose - There's currently no obvious place to merge to and I suspect that Optical films have other applications outside of LCDs. ~KvnG 14:22, 27 February 2014 (UTC)
 * Support - I don't see anyone trying to expand the optical film article, and having a merge for now is fine, where it discusses it's use in liquid-crystal displays. If it's used elsewhere, and the same thing occurs (one stubby sentence) then it can become a disambiguation page perhaps. SarahStierch (talk) 19:55, 8 April 2014 (UTC)
 * Oppose Per Kvng. The term "optical film" is problematic in that it has some widely varying meanings.  The article is probably a long term stub wreck partially because of that; nobody with combined expertise, article architecture and wikipedia ability has come along to remedy the situation. LCD is just one of many uses / meanings.  North8000  (talk) 20:30, 8 April 2014 (UTC)
 * Oppose - Per KvnG and User talk:North8000. "Optical film" is well sourced on Scholar and Google Books relating to the chemical and industrial usage. This is about far more than LCDs; it includes OLEDs plus ARs. Related discussions have occurred at Talk:Thin-film optics.
 * Oppose. Better off as a dab page. 203.109.161.2 (talk) 20:52, 29 July 2015 (UTC)
 * Oppose, per all the reasons above. The IP editor above finally turned it into a disambig page anyways, thank god. Think I'll close this now. If any of you have any objections (or anyone else for that matter), you can feel free to reopen it.

Bullet point: Hard to read when wearing polarized sunglasses.
Any chance of a source for that "disadvantage" bullet point? Contributor is: https://en.wikipedia.org/wiki/Special:Contributions/199.61.25.252 — Preceding unsigned comment added by DavidBoden (talk • contribs) 21:42, 19 May 2014 (UTC)

There might be a clearer explanation of how colour is generated
I think this article could use a brief explanation of how a colour display is set up, with sub pixels etc - in the sections concerning the principles of operation.81.191.184.223 (talk) 21:56, 13 August 2015 (UTC)

Error in Disadvantages section
In the Disadvantages section under Input lag the first sentence "Input lag, because the LCD's A/D converter waits for each frame to be completely been output before "drawing" it to the LCD panel." has a problem. Something is missing after the word completely. Robertdirosario (talk) 06:02, 21 February 2017 (UTC)

Fav Lcd
Backlit LCD(s) Are My Favorite. — Preceding unsigned comment added by Dinan Blueje (talk • contribs) 02:39, 6 June 2017 (UTC)

Merger proposal
There's an article titled LCD television, which deals with no particularities of LCD displays featuring TV tuners, numerous sections even dealing explicitly with computer monitors. Perhaps some of the info there is worth merging into this article, but I'd say we have two articles dealing with the same subject of matter. --uKER (talk) 18:28, 28 December 2017 (UTC)

Sources supporting (or contradicting) the claim that LCDs emit no light of their own
I added failed verification and citation needed tags on the two occurrences of the claim that LCDs emit no light of their own. I'm not an expert, but I believe it's common conventional knowledge that this is correct, however, it's such a central aspect of the topic that it requires a robust citation. I have a less-than-ideal source for the claim, an article published on FESPA's website, the qualifier owing to FESPA's realm of expertise being printing on physical media as opposed to electronics or electromagnetic radiation.

Maybe someone could source a better reference?

MagnusOxlund (talk) 17:56, 16 March 2020 (UTC)


 * Have added a recent publication in a reputable journal showing that light transmission is controlled by LCDs, without light emission by the screen itself.--BBCLCD (talk) 11:05, 17 March 2020 (UTC)

ZBD Liquid Crystal Displays
Please conisder adding updated information on ZBD LCDs under the "Zero-Power" (bistable) Display section:

The ZBD LCD technology was invented in 1995 and uses a submicron grating surface to stabilise two different orientations of an adjacent nematic liquid crystal. These states lead to either high or low pretilt in the LC close to the surface and can thus allow two optically distinct states when the grating is used as one of the surfaces in an LC cell. The bend and splay distortion of the LC material close to the grating leads to regions with macroscopic flexoelectric polarisation. It is possible to use the polarity of applied electrical pulses to couple to the flexoelectricity and thus select either the high or low tilt state. The technology is manufactured by replication of an inverse structure (on a polymer foil) into a UV curing resin coated onto the LCD glass. After UV cure and separation, the LCD glass is assembled as a standard LCD and filled with standard LC material.



The ZBD LCD offers ‘infinite multiplexibilty’. There is a distinct threshold between the two states which allows passive matrix addressing of many thousands of lines. This contrasts with many other low power display modes which require a TFT backplane (e.g. Eink EPD, Clearink EPD, electrowetting, electrochromic, phase change).

The technology has been widely deployed in low power electronic shelf edge label products. Since 2019, the ZBD LCD technology has been exclusively owned, manufactured and marketed by New Vision Display. Aubsabs222 (talk) 21:47, 18 May 2020 (UTC)

Requested move 20 February 2023

 * The following is a closed discussion of a requested move. Please do not modify it. Subsequent comments should be made in a new section on the talk page. Editors desiring to contest the closing decision should consider a move review after discussing it on the closer's talk page. No further edits should be made to this discussion.

The result of the move request was: no consensus. Favonian (talk) 16:09, 6 March 2023 (UTC)

Liquid-crystal display → LCD – Per MOS:ACROTITLE: "Acronyms should be used in a page name if the subject is known primarily by its abbreviation and that abbreviation is primarily associated with the subject". That is the case here. It is also more WP:CONSISTENT with LCD television, LCD projector, LCD classification, LCD crosstalk, Blue phase mode LCD and List of LCD matrices. PhotographyEdits (talk) 13:52, 20 February 2023 (UTC) — Relisting.  Arbitrarily0   ( talk ) 16:06, 27 February 2023 (UTC) The discussion above is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.
 * Support Rreagan007 (talk) 19:40, 20 February 2023 (UTC)
 * Oppose for the same reason the LED and MLM requested moves should not take place: we do not use ambiguous abbreviations as article titles.  — SMcCandlish ☏ ¢ 😼  07:19, 23 February 2023 (UTC)
 * It is not ambigious. There is no significant other meaning of the abbreviation and MOS:ACROTITLE applies. PhotographyEdits (talk) 08:36, 23 February 2023 (UTC)
 * It is ambiguous, or LED (disambiguation) would not exist.  — SMcCandlish ☏ ¢ 😼  23:54, 27 February 2023 (UTC)
 * Probably you mean LCD (disambiguation). Dicklyon (talk) 10:16, 28 February 2023 (UTC)
 * Comment if no other comments will be posted, I think it should be moved because the only argument against it was not opposed. Then it's not a 'no consensus'. PhotographyEdits (talk) 17:38, 27 February 2023 (UTC)
 * It should not be moved, as the only support for the idea provides no rationale, and the nom's rationale is faulty. The closer also needs to consider all the rationales in the previous RM discussion; this RM is just a tendentious rehash.  — SMcCandlish ☏ ¢ 😼  23:58, 27 February 2023 (UTC)
 * Oppose per SMcCandlish. Tony (talk)  00:15, 28 February 2023 (UTC)
 * Oppose – Millions of us are more familiar with least common denominator than with liquid-crystal display. No need to make titles so ambiguous.  In fact, it would be better to undo the primary redirect and put the disambig page at LCD.   Dicklyon (talk) 10:16, 28 February 2023 (UTC)
 * Comment: they are not ambiguous as one of the terms is consistently far more significant in terms of pageviews, which is the current page. See the |Lowest_common_denominator Pageview Analysis page. In common usage, the term LCD is also far more widely used than Liquid-crystal display. That means it should be moved per MOS:ACROTITLE. PhotographyEdits (talk) 12:55, 28 February 2023 (UTC)
 * Support per nom, and COMMONNAME. Also, this isn't an ambiguous title IMO, clearly PRIMARY.--Ortizesp (talk) 16:43, 28 February 2023 (UTC)
 * Comment I'm pretty surprised hearing the we do not use ambiguous abbreviations as article titles argument – we have WP:PRIMARYREDIRECT for a reason, and, as far as I can tell, has redirected here since 2005; I would be staunchly opposed to replacing it with a dab page. We have the space agency at NASA despite existence of NASA (disambiguation). That being said, the bar for moving a page to its ACROTITLE has been traditionally held (unreasonably?) high, as can be evidenced by Talk:Lysergic_acid_diethylamide/Archive_7. I'm neutral on this particular issue, since "liquid-crystal display" is a rather well-known expansion, and so "known primarily by its abbreviation" is only correct for certain values of "primarily". No such user (talk) 15:45, 1 March 2023 (UTC)
 * @No such user I wonder what 'certain values' you are referring to. In highly technical circles it is commonly known as an LCD and in common popular marketing it is known as an LCD too. PhotographyEdits (talk) 14:25, 2 March 2023 (UTC)
 * "Certain values" was a tongue-in-cheek – I'll quote from the above 2009 RM: it requires strong evidence of "known by acronym only" before moving in that direction and I would emphasisse "almost exclusively known only by its acronym". The wording of ACROTITLE seems to have been different in 2009, but most people still apply the stringent interpretation that "primarily" means "known exclusively by acronym" (which is clearly the case for LSD but that's the argument for a future RM there.) No such user (talk) 14:52, 2 March 2023 (UTC)