Private Ryan
Skilled
I found this really informative article on the net about LCDs. Plus a lot of jargon talk related to LCD monitors has been explained which would really help a newbie out there to buy an LCD monitor.
I would like to add that this article is not for the gurus here and is meant for the newbies. I too didnt know a lot of all tht jargon used when it came to LCDs and this article really helped clear a lot of doubts. So i thought of posting it here for others like me so that they are equipped with all the knowledge b4 they go out to buy their monitors n not regret their purchase later.
LCD Terms
LCD: Liquid Crystal Display
TFT: Thin Film Transistor
VGA: Video Graphic Array
DVI: Digital Visual Interface
Contrast Ratio: Light intensity between black and white. Higher contrast ratios = sharper image
Luminance: Brightness level on a LCD. Measured in nits or candelas (cd) per square meter (cd/m2). 1 nit = 1 cd/m2.
Viewing Angles: the degree of angle at which you can view the screen sideways (horizontal angle) and top/bottom (vertical angle) without losing image quality.
Response Time: The speed of a pixel's color transition. Measured in milliseconds (ms).
Tr: Time Rise. (Usually) the response time from 90% to 10% brightness. Sometimes measured from 100% on to off.
Tf: Time Fall. (Usually) the response time from 10% to 90% brightness. Sometimes measured from off to 100% on.
TrTf: Time Rising (Tr) & Time Falling (Tf). Simply the sum between Tf and Tr (not the average). E.g. 5ms Tr + 3ms Tf = 8ms TrTf
GTG: Gray-To-Gray or Grey-To-Grey. Response time measurement from one grey scale to another, and vice versa. The lower voltage required to make this transition makes it slower than White/Black, which is the reason why most VA panels are slower (because of more colors).
White/Black: or White-To-Black. Response time measurement from fully black to fully white, and vice versa. The higher voltage required to make this transition makes it quicker than GTG, which is the reason why most TN panels are faster (because of less colors).
Motion Blur: When the screen blurs in fast motion pictures due to slow response times
Ghosting: When the screen leaves a ghost like trail in fast motion pictures due to slow response times. Ghosting is a step further from motion blur, and should not be confused
Native Resolution: The actual measurement in pixels of the screen area
Dead pixels/Stuck pixels: A pixel that remains 'on' or 'off', meaning that it is always illuminated, unlit, or stuck on one color regardless of the image the LCD monitor displays can also be called a dead pixel.
Mura Effect: An imperfection in the screen's homogeneity usually caused when the panel is not properly sealed or when too much pressure is applied on the screen. Most common in lower grade production.
Color Banding: Inacurate color representation in a color scale.
Bezel: Plastic or metal frame surrounding the panel.
VESA: Video Electronics Standards Association. Site = VESA
VESA mount: VESA recommendation indicating that the monitor can be mounted on a desk or wall.
-------------------------------------------------------------------
Key:
computer Display Standard = Resolution (Aspect Ratio)
List (PC res.):
MDA = 720×350 (72:35)
CGA = 160×200 (4:5), 320×200 (16:10), 640×200 (16:5)
Hercules = 720×348 (60:29)
Professional Graphics Controller = 640×480 (4:3)
MCGA = 320×200 (16:10), 640×480 (4:3)
8514 = 1024×768 (4:3)
VGA = 320×200 (16:10), 640×350 (64:35), 640×480 (4:3), 720×400 (9:5)
SVGA = 800×600 (4:3)
XGA = 640×480 (4:3), 1024×768 (4:3)
QVGA = 320×240 (4:3)
SXGA = 1280×1024 (5:4)
UXGA = 1600×1200 (4:3)
WUXGA = 1920×1200 (16:10)
WXGA = 1280×720 (16:9)
WSXGA / WXGA+ = 1440×900 (16:10)
List (TV res.):
Note: Some TV res. are the same as some PC res.
Progressive: ( -p extension )
VGA 640x480
480p 720x480
576p - PAL Plus 720x576
720p 1280x720
1080p 1920x1080
Interlaced: ( -i extension )
Broadcast NTSC 440x330 (Stretched to VGA)
DV NTSC 480i ~720x350 - ~720x400
DV-PAL-576i 720x405
HDV & Broadcast 1080i 1440x810 (Stretched to 1080p)
Screen resolutions are mentioned again in the "Common Aspect Ratios" section below, but with comparisons in aspect ratio and scale.
Interfaces:
VGA
VGA (Video Graphic Array): analog conector that sends information to the monitor as a Red, Green, and Blue (RGB) signal. Nearly all CRTs have it, and most LCDs support it. First introduced by IBM in the mid 80s and still remains as the most popular solution to date.
VGA Pin Arrangement:
VGA to Component Mod:
Here is a mod for those who want to connect their PC to an HDTV with no VGA connectors and without having to buy one of those expensive converters.
I havent tryed this mod myself, but it seems plausible since a VGA connector simply sends a RGB signal to the monitor and the rest is just to comunicate with the monitor for settings and info.
DVI
DVI (Digital Visual Interface) digital connector that send information to the monitor in eather a digital signal of over 160mhz
Can supports UXGA and HDTV resolutions with a single set of links. Higher resolutions can be supported with a dual set of links.
Types of DVI Connectors:
DVI Pin Arrangement:
LCD vs. CRT:
Here are some reasons why to buy a LCD over a CRT
No Flickering:
LCDs don’t flicker because all pixels on a LCD refresh themselves, wile a CRT has to constantly refresh the entire image with 3 electron beamps, each of a different color. Red, Green, and Blue.
You can notice flickering when there are fast motions on a CRT. You can see how the screen refreshes a frame by taking a camera and viewing the CRT though the camera. In real time it’s really fast and invisible to the naked eye in most situations, but in the camera it looks slower and you may notice a difference in brightness between frames.
Focus & Perfect Geometry:
LCDs are made up of millions of small colored pixels that are lighted with a “back lightâ€. They are equally proportional in the entire surface, so the image looks equally well on the entire screen
CRT use an electron beam that projects a series of colours to a curved lens. Newer CRT have a lens hat convert the curve surface to a flat surface. Because of this, as you move away from the center of a CRT's screen, it becomes less sharp and more blurry
Sharpness:
LCD run at a native resolution, wile CRT compresses the image as you raise the resolution, making it less sharp and more blurry in higher resolutions.
Durability:
the only part on a LCD that ages is the “back lightâ€. LCD commonly have a backlight that has a half-life of 50,000 hours. Afther that time period, the LCD will only lose half the brigtness. If the “back light†dies on a LCD, it can be replaced.
CRT ages in two ways: An oxide layer forms on the cathode of the electron gun, decreasing beam current; and the phosphor ages and becomes less efficient.
Most CRT’s half-life is about 10,000 and 20,000 hours. After that time spawn, the CRT may lose brightness and/or image quality. As you can see, a LCD can las between 2-5 times more than a CRT
Power consumption:
The power required to run a LCD is about 1/3 the power needed to run a CRT.
Because of less energy needed, less heat is released.
Low emissions:
An LCD is essentially emission-free, while a CRT monitor can generate electric, magnetic and even X-ray emissions due to the high-voltage power supply necessary to drive the CRT. An LCD causes no electromagnetic interferente
In other words, NO MORE HEADACHES
Ergonomics:
As many of you may know, LCD are a lot more thinner than a CRT
LCD can also be adapted in many ways for the user’s needs.
You can also buy a wall mount to help you place the LCD anywhere you want.
Size:
LCD are not also thinner than CRT, but they are larger too.
CRT are measured by the display size, so the viewable size is smaller than described.
LCD are measured by the viewable area, so a 20†LCD is larger than a 20†CRT
CRT advantage
The only advantage with CRTs is response time, darkness levels, and price.
Right now, an average CRT can have a response time below 2ms and can have contrast ratios above 1000:1 and LCDs could cost more than two times a CRT at the same recommended resolution.
CRTs are already mature in technology, so you shouldnt see huge improvements on latter releases
LCD is a new tech and each new release is an improvement in LCD technology. As new tech is released, LCDs become better and more afordable, and will outperform CRTs
LCD Tech:
The Truth About Response Times:
The problem with response times is that companies quote their monitor's with the best possible response time and not its average response time.
This is further complicated by the fact that response times on different panels means different things.
Currently, these are the different LCD panels on the market:
* TN
* S-IPS
* PVA/MVA.
Depending on the type of panel, there can be large differences in the monitor's response time.
Response times are measured on how fast a pixel changes from black to white or grey to grey.
Traditionally, a 25ms S-IPS LCD panel works as fast as a 16ms TN panel for the wide range of black to light grey.
Only when a pixel is going from pure black to pure white was the 16ms TN panel actually faster.
On the other hand, a PVA or MVA monitor advertised at 25ms when going from black to white may very well need 80ms to transition from black to grey!
Since then, TN panels have been pushed to the lowest response times of any other panel... the fastest ones today rates at 4ms.
TN panels have become the "gamer's panel" for some time because it sacrifices colour representation, image quality and viewing angles for the best response time possible. All these panels display 6-bit colour, which unlike the other panels, means poorer colour quality.
This isn't a problem in games as the 6-bit spectrum offers more than enough colour accuracy to match even the most graphically demanding game out there. However, for watching movies, picture editing or even general desktop use, the difference from these panels to the S-IPS and PVA/MVA is noticeable.
S-IPS panels typically offer good viewing angles with accurate 8-bit colour representation. Screen contrast, however, remains poorer than other panels.
With recent advances in TN and PVA/MVA panels, these screens have been left behind as they remain slower than TN panels and offer less visual quality than PVA/MVA panels.
Latest news within the industry suggests these panels will soon be discontinued.
Traditionally, PVA/MVA panels on the other hand are famed for deep black levels, superb contrast ratios and 8-bit colour... all at the expense of speed.
Recently, however, MVA panels have made a huge technological leap with the development of very fast 8ms panels. The average response times on this panels are better than 8ms TN panels.
PVA panels are commonly seen on older & larger LCD displays. Although they offer similar colour and picture quality as a MVA panel, they haven’t improved significantly in terms of response time. Recent reviews suggest that the fastest PVA panels rated at 16ms fail to show signficant improvement in response time over older 25ms PVA panels
When you consider that the PVA/MVA panels retain their great image quality and perform better at the same refresh rate, these panels are likely to soon phase out both the S-IPS and TN panels.
Here is a graph comparing one of the fastest panels from Samsung's TN panels vs. AU Optronic's 8ms MVA panel.
This essentially compares TN vs.MVA at 8ms, not Samsung vs AU Optronic
Common Aspect Ratios:
5:4 = 640×512, 720×576, 1280×1024, 1800×1440, 2560×2048, etc.
4:3 = 320×240, 480×360, 640×480, 800×600, 832×624, 1024×768, 1152×864, 1280×960, 1400×1050, 1600×1200, 1920×1440
16:10 = 320×200, 1440×900, 1680×1050, 1920×1200, 2560×1600, 3840×2400, 7680×4800, etc.
16:9 = 1280×720, 1600×900, 1920×1080, etc.
As you can see, 1280×1024 is the only common resolution on a 5:4 ratio.
That's why games are showing up with 1280×960 resolutions, since 4:3 ratio monitors are more common than 5:4 monitors
16:9 is wider than 16:10 and it’s what you mostly see as wide-screen movies
Only a few games and applications support 16:10 and 16:9
Games running on the Source, CryTech, WoW, Doom3, and other engines can be setup or hacked to support 16:10 and 16:9 ratios. This may give you an advantage over everyone since you will have more viewable are on the sides.
Here is a link comparing Counter Strike: Source with 4:3 and 16:9 aspect ratios:
Widescreen! - Halflife2.net
By overlaping them, you can see how much viewable area is being lost..
-------------------------------------------------------------------------------------
I hope, the information provided here is accurate.
I would like to add that this article is not for the gurus here and is meant for the newbies. I too didnt know a lot of all tht jargon used when it came to LCDs and this article really helped clear a lot of doubts. So i thought of posting it here for others like me so that they are equipped with all the knowledge b4 they go out to buy their monitors n not regret their purchase later.
LCD Terms
LCD: Liquid Crystal Display
TFT: Thin Film Transistor
VGA: Video Graphic Array
DVI: Digital Visual Interface
Contrast Ratio: Light intensity between black and white. Higher contrast ratios = sharper image
Luminance: Brightness level on a LCD. Measured in nits or candelas (cd) per square meter (cd/m2). 1 nit = 1 cd/m2.
Viewing Angles: the degree of angle at which you can view the screen sideways (horizontal angle) and top/bottom (vertical angle) without losing image quality.
Response Time: The speed of a pixel's color transition. Measured in milliseconds (ms).
Tr: Time Rise. (Usually) the response time from 90% to 10% brightness. Sometimes measured from 100% on to off.
Tf: Time Fall. (Usually) the response time from 10% to 90% brightness. Sometimes measured from off to 100% on.
TrTf: Time Rising (Tr) & Time Falling (Tf). Simply the sum between Tf and Tr (not the average). E.g. 5ms Tr + 3ms Tf = 8ms TrTf
GTG: Gray-To-Gray or Grey-To-Grey. Response time measurement from one grey scale to another, and vice versa. The lower voltage required to make this transition makes it slower than White/Black, which is the reason why most VA panels are slower (because of more colors).
White/Black: or White-To-Black. Response time measurement from fully black to fully white, and vice versa. The higher voltage required to make this transition makes it quicker than GTG, which is the reason why most TN panels are faster (because of less colors).
Motion Blur: When the screen blurs in fast motion pictures due to slow response times
Ghosting: When the screen leaves a ghost like trail in fast motion pictures due to slow response times. Ghosting is a step further from motion blur, and should not be confused
Native Resolution: The actual measurement in pixels of the screen area
Dead pixels/Stuck pixels: A pixel that remains 'on' or 'off', meaning that it is always illuminated, unlit, or stuck on one color regardless of the image the LCD monitor displays can also be called a dead pixel.
Mura Effect: An imperfection in the screen's homogeneity usually caused when the panel is not properly sealed or when too much pressure is applied on the screen. Most common in lower grade production.
Color Banding: Inacurate color representation in a color scale.
Bezel: Plastic or metal frame surrounding the panel.
VESA: Video Electronics Standards Association. Site = VESA
VESA mount: VESA recommendation indicating that the monitor can be mounted on a desk or wall.
-------------------------------------------------------------------
Key:
computer Display Standard = Resolution (Aspect Ratio)
List (PC res.):
MDA = 720×350 (72:35)
CGA = 160×200 (4:5), 320×200 (16:10), 640×200 (16:5)
Hercules = 720×348 (60:29)
Professional Graphics Controller = 640×480 (4:3)
MCGA = 320×200 (16:10), 640×480 (4:3)
8514 = 1024×768 (4:3)
VGA = 320×200 (16:10), 640×350 (64:35), 640×480 (4:3), 720×400 (9:5)
SVGA = 800×600 (4:3)
XGA = 640×480 (4:3), 1024×768 (4:3)
QVGA = 320×240 (4:3)
SXGA = 1280×1024 (5:4)
UXGA = 1600×1200 (4:3)
WUXGA = 1920×1200 (16:10)
WXGA = 1280×720 (16:9)
WSXGA / WXGA+ = 1440×900 (16:10)
List (TV res.):
Note: Some TV res. are the same as some PC res.
Progressive: ( -p extension )
VGA 640x480
480p 720x480
576p - PAL Plus 720x576
720p 1280x720
1080p 1920x1080
Interlaced: ( -i extension )
Broadcast NTSC 440x330 (Stretched to VGA)
DV NTSC 480i ~720x350 - ~720x400
DV-PAL-576i 720x405
HDV & Broadcast 1080i 1440x810 (Stretched to 1080p)
Screen resolutions are mentioned again in the "Common Aspect Ratios" section below, but with comparisons in aspect ratio and scale.
Interfaces:
VGA
VGA (Video Graphic Array): analog conector that sends information to the monitor as a Red, Green, and Blue (RGB) signal. Nearly all CRTs have it, and most LCDs support it. First introduced by IBM in the mid 80s and still remains as the most popular solution to date.
VGA Pin Arrangement:
VGA to Component Mod:
Here is a mod for those who want to connect their PC to an HDTV with no VGA connectors and without having to buy one of those expensive converters.
I havent tryed this mod myself, but it seems plausible since a VGA connector simply sends a RGB signal to the monitor and the rest is just to comunicate with the monitor for settings and info.
DVI
DVI (Digital Visual Interface) digital connector that send information to the monitor in eather a digital signal of over 160mhz
Can supports UXGA and HDTV resolutions with a single set of links. Higher resolutions can be supported with a dual set of links.
Types of DVI Connectors:
DVI Pin Arrangement:
LCD vs. CRT:
Here are some reasons why to buy a LCD over a CRT
No Flickering:
LCDs don’t flicker because all pixels on a LCD refresh themselves, wile a CRT has to constantly refresh the entire image with 3 electron beamps, each of a different color. Red, Green, and Blue.
You can notice flickering when there are fast motions on a CRT. You can see how the screen refreshes a frame by taking a camera and viewing the CRT though the camera. In real time it’s really fast and invisible to the naked eye in most situations, but in the camera it looks slower and you may notice a difference in brightness between frames.
Focus & Perfect Geometry:
LCDs are made up of millions of small colored pixels that are lighted with a “back lightâ€. They are equally proportional in the entire surface, so the image looks equally well on the entire screen
CRT use an electron beam that projects a series of colours to a curved lens. Newer CRT have a lens hat convert the curve surface to a flat surface. Because of this, as you move away from the center of a CRT's screen, it becomes less sharp and more blurry
Sharpness:
LCD run at a native resolution, wile CRT compresses the image as you raise the resolution, making it less sharp and more blurry in higher resolutions.
Durability:
the only part on a LCD that ages is the “back lightâ€. LCD commonly have a backlight that has a half-life of 50,000 hours. Afther that time period, the LCD will only lose half the brigtness. If the “back light†dies on a LCD, it can be replaced.
CRT ages in two ways: An oxide layer forms on the cathode of the electron gun, decreasing beam current; and the phosphor ages and becomes less efficient.
Most CRT’s half-life is about 10,000 and 20,000 hours. After that time spawn, the CRT may lose brightness and/or image quality. As you can see, a LCD can las between 2-5 times more than a CRT
Power consumption:
The power required to run a LCD is about 1/3 the power needed to run a CRT.
Because of less energy needed, less heat is released.
Low emissions:
An LCD is essentially emission-free, while a CRT monitor can generate electric, magnetic and even X-ray emissions due to the high-voltage power supply necessary to drive the CRT. An LCD causes no electromagnetic interferente
In other words, NO MORE HEADACHES
Ergonomics:
As many of you may know, LCD are a lot more thinner than a CRT
LCD can also be adapted in many ways for the user’s needs.
You can also buy a wall mount to help you place the LCD anywhere you want.
Size:
LCD are not also thinner than CRT, but they are larger too.
CRT are measured by the display size, so the viewable size is smaller than described.
LCD are measured by the viewable area, so a 20†LCD is larger than a 20†CRT
CRT advantage
The only advantage with CRTs is response time, darkness levels, and price.
Right now, an average CRT can have a response time below 2ms and can have contrast ratios above 1000:1 and LCDs could cost more than two times a CRT at the same recommended resolution.
CRTs are already mature in technology, so you shouldnt see huge improvements on latter releases
LCD is a new tech and each new release is an improvement in LCD technology. As new tech is released, LCDs become better and more afordable, and will outperform CRTs
LCD Tech:
The Truth About Response Times:
The problem with response times is that companies quote their monitor's with the best possible response time and not its average response time.
This is further complicated by the fact that response times on different panels means different things.
Currently, these are the different LCD panels on the market:
* TN
* S-IPS
* PVA/MVA.
Depending on the type of panel, there can be large differences in the monitor's response time.
Response times are measured on how fast a pixel changes from black to white or grey to grey.
Traditionally, a 25ms S-IPS LCD panel works as fast as a 16ms TN panel for the wide range of black to light grey.
Only when a pixel is going from pure black to pure white was the 16ms TN panel actually faster.
On the other hand, a PVA or MVA monitor advertised at 25ms when going from black to white may very well need 80ms to transition from black to grey!
Since then, TN panels have been pushed to the lowest response times of any other panel... the fastest ones today rates at 4ms.
TN panels have become the "gamer's panel" for some time because it sacrifices colour representation, image quality and viewing angles for the best response time possible. All these panels display 6-bit colour, which unlike the other panels, means poorer colour quality.
This isn't a problem in games as the 6-bit spectrum offers more than enough colour accuracy to match even the most graphically demanding game out there. However, for watching movies, picture editing or even general desktop use, the difference from these panels to the S-IPS and PVA/MVA is noticeable.
S-IPS panels typically offer good viewing angles with accurate 8-bit colour representation. Screen contrast, however, remains poorer than other panels.
With recent advances in TN and PVA/MVA panels, these screens have been left behind as they remain slower than TN panels and offer less visual quality than PVA/MVA panels.
Latest news within the industry suggests these panels will soon be discontinued.
Traditionally, PVA/MVA panels on the other hand are famed for deep black levels, superb contrast ratios and 8-bit colour... all at the expense of speed.
Recently, however, MVA panels have made a huge technological leap with the development of very fast 8ms panels. The average response times on this panels are better than 8ms TN panels.
PVA panels are commonly seen on older & larger LCD displays. Although they offer similar colour and picture quality as a MVA panel, they haven’t improved significantly in terms of response time. Recent reviews suggest that the fastest PVA panels rated at 16ms fail to show signficant improvement in response time over older 25ms PVA panels
When you consider that the PVA/MVA panels retain their great image quality and perform better at the same refresh rate, these panels are likely to soon phase out both the S-IPS and TN panels.
Here is a graph comparing one of the fastest panels from Samsung's TN panels vs. AU Optronic's 8ms MVA panel.
This essentially compares TN vs.MVA at 8ms, not Samsung vs AU Optronic
Common Aspect Ratios:
5:4 = 640×512, 720×576, 1280×1024, 1800×1440, 2560×2048, etc.
4:3 = 320×240, 480×360, 640×480, 800×600, 832×624, 1024×768, 1152×864, 1280×960, 1400×1050, 1600×1200, 1920×1440
16:10 = 320×200, 1440×900, 1680×1050, 1920×1200, 2560×1600, 3840×2400, 7680×4800, etc.
16:9 = 1280×720, 1600×900, 1920×1080, etc.
As you can see, 1280×1024 is the only common resolution on a 5:4 ratio.
That's why games are showing up with 1280×960 resolutions, since 4:3 ratio monitors are more common than 5:4 monitors
16:9 is wider than 16:10 and it’s what you mostly see as wide-screen movies
Only a few games and applications support 16:10 and 16:9
Games running on the Source, CryTech, WoW, Doom3, and other engines can be setup or hacked to support 16:10 and 16:9 ratios. This may give you an advantage over everyone since you will have more viewable are on the sides.
Here is a link comparing Counter Strike: Source with 4:3 and 16:9 aspect ratios:
Widescreen! - Halflife2.net
By overlaping them, you can see how much viewable area is being lost..
-------------------------------------------------------------------------------------
I hope, the information provided here is accurate.
