Talk:Liquid crystal display

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Contents

[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

[edit] types of crystals

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] process on lcd manufacture

I wold like to have a copy on the general procedure on how to manufacture lcd. -- 203.177.151.10 18 April 2005

[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] Drawback?

  • 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)

[edit] Crystal Liquids 'R' Us

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

[edit] Toothpaste for small scratches

Recently a moron scratched my LC monitor. It was a smal but visible scratch that drove me nuts. I wanted to kill that person. I used damp cloth and a tiny amount of a non-abrasive toothpaste and it worked wonders! The scratch is completely gone!

Hope this helps anyone who has scratches on their monitors.

Interesting. Not sure where this belongs. Wikipedia seems to be somewhat limited by the fact that it is an encyclopedia, but maybe this would fit if someone else can corroborate. Reference desk is the place that people go to get more general questions answered. --Whiteknox

[edit] inverted colour

If you take off the front filter on a calculator's LCD display, flip it over and re-insert it, your background colour will be black and the numbers will show up as white. really cool modification, especially if you want glowing numbers.

[edit] Help with cleaning a Glossy LCD Screen

I have recently bought a laptop, and it came with a glossy LCD screen. It is the first Glossy LCD screen I've owned, so I'm not sure how to properly clean it. My dad says that regular cleaning methods(i.e. damp cloth, sprays and wipes for glass) could mess up the screen, so I've avoided cleaning it. Dust is easy enough to remove, but things like fingerprints and this annoying little grey spot of something remain withough being phased. What is best for it? While I'm at it, I may as well my other questions about LCD's:

  • How much pressure is safe for the screen? For instence, I will often, by nessicity while carrying my laptop, find my hand pressing hard enough, from the back, to cause distortion. How much (about) can the screen take?
  • Will sudden shock, say a band from a doorframe, be dangerous?
  • What are the advantages/disadvantges of Glossy vs. Matte displays?

Thank you in advance. --RockMaster 01:09, 15 November 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)


[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

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