Overview of Display Device Types and their specifications

All of the PCs that we use need to have some displays. Normally there are the standard monitors, but they now are available in various varieties like LEC, LED. The evolution of the displays has not just only made the space that they contain become less, but also has made them more efficient. But, there are some certain disadvantages as well which are associated with the new types of displays, like in the CRT's, one could see the screen from any angel since the screen shape was a bit round. Now the flat screen has made the restriction that only that person, who is viewing it from the 180 degree angle, can see the screen properly. Following are the few displays types and their features in which these monitors are available;





Types:

The types of the displays that are being used currently and have been used since long are as follows;


CRT: CRT stands for Cathode Ray Tubes and is the very old style display which uses the florescent blue tube in itself and it projects the electrons to the screen at a time. These projections are responsible for creating the images on the screen. These monitors are pretty heavy and have been configured for some various sizes. They are available in the sizes of 15 inches, 19 inches and the 21 inches. Also, the cathode ray tubes have some other types of options as well. The thing is, the large would be the screen, the larger would be the tube and due to that, the weight would increase as well. Some of them come along with some specified types of the resolutions which can be 1028 x 1025, XGA etc. these displays contained the refresh rate which is that how fast the electrons can actually get sprayed on the screen and how fast the image can be changed and produced.


LCD: now the time has changed and CRT has been obsoleted. Now the new technology is of LCDs. It is the very common type of the display that one can find anywhere. This contains the liquid crystals and these displays do not contain the tubes. So, there isn't any electronic gun as well and one doesn't have to worry about the electrons painting the display. Instead, there is a back light that always keeps the liquid crystal display on. The power is given to a transistor which then repolarizes light and that's what enables the light to come out and show a specific colour. Since there is always a light that is shining through, the LCD displays do not contain the black set blacks. Also, if one does lots of the graphical work and hence the lots of work have to be shown, one should ensure that the backlight is always there and quality of LCD is pretty high.


LED: LED is another new technology which also has captured many of the consumer's choices. It is known as led since the backlight used in it is normally a fluorescent light and it is used instead of using a normal backlight. But, there is always the LCD there which gives the screen information and helps us having the view. So, it's even better if it is called LED Backlit LCD. The LED technology has been embedded in many ways. One of the ways is to have the LEDs at the edge of screen. Inside the display, there is a component named defuser which is responsible for the distribution of the light that comes through the whole back. Another method to use this technology is the usage of a whole array of LEDs. This array isn't just there on the edges, but they are spread across the all back side of the display. Hence the display gets lighter since it has more control of it. There is new type of LED too which has been introduced. It's called the organic LED display. It is created of some organic material which lights up if it is provided with a current. The cost of such LED is pretty low and this LED is mostly used in the mobile phones due to it fast speed and the good response time. The angel of viewing is also pretty wide. It all happens since the material used inside it is pretty organic.


Plasma: This is another new invention and it is named as the plasma display since there are some really small sized cells are present there. These cells are of the Nobel gases and when the voltage is provided to them, the ultra-violate ray is generated and the each light is brightened and hence the light is emitted through the display. Now, the phosphorus is being used instead of these cells and hence the colour quality has been improved a lot. So for those who work for the video editing and they require some good displays, this one is the good option. They use much power and the radio interfaces are put off as well. The interesting fact is that if one is living at some place which is above the sea level, the display won't be so effective so if one is living on some mountain area, he should make sure to check whether the specifications would work or not.


Projector: The projectors are now also being used and almost every organization use this to spread the information on the screen. The data can be projected at the wall and it can become visible to many people at the same time. These are also known as the CD projectors but the truth is, that there are many various technologies which are being used for that displays and the LCD is not the only option.


OLED: This technology is the new technology. It stands for the Organic Light emitting Diodes. This technology is the flat light emission one and it is made through some thin films which are organic and they are placed between two conductors. Whenever it gets hit by the electricity, the bright light comes out of it. These displays do not require some backlight and they are pretty thinner. So, they are better than all the LED and the LCD since they don't use the backlight to project an image.



Refresh Rates

Refresh rate is actually important when one talks about the CRT displays. The rate was the measurement to tell how fast and efficient a CRT display is. The rate describes that how fast an electrons gun can throw electrons on the screen and how fast the display can be shown. The refresh rates for the devices, which were considered good, were between 65 and 75. Also, sometimes they reach 85 hertz as well. It meant that the screen could be refreshed around 85 times in just one second. But the thing is, the when the screens got bigger, it became a problem since the electrons has to cover the wider areas and the number of screen updates got reduced dramatically. When the refresh rate turned to 72 Hz or near it, that used to be a big problem since at the rate, the human eye started flickering. Also, it became so annoying while watching the display. Also, the important thing is that the display which could support some resolution desired by the people was shown at above 72 Hz. But the modern technology has allowed the LED and the LCD displays to update every single pixel on the screen instantly and hence one doesn't have to face the flickering or any other problem in viewing the display.



Resolution

Doesnt matter what kind of display is owned by one. The most important thing that really matters is that what the resolution of that display is. The resolution is normally presented with the number of the pixels wide, the width, and the number of the pixels height. It indicates the pixel dimension, which is the total number of the pixel in every direction, regardless of the fact that the size is big or small. The XGA screens are the 1024 by 788 pixels. The other one is the SXGA, and has 1024 x 1024 pixels and they both are considered really well for the resolution. But now the pixels have been improved too and one can find the displays with some really high pixels which give some quality screen to the users.


Native Resolution: The LCD has some important specification and it is known as the native resolution for that display. When the CRTs were used, one could simply change the pixel size since it was in the tube. But now on the LCDs, it cannot be changed. The reason is that it would always have the specific number of the pixels high and the certain amount of the pixel wide. On the computers, the resolution can be changed easily and quickly. Also, the LCDs we use these days can adjust themselves according to that resolution that has been set by the user. If there is some mismatch that is happened between the pixel high and the wide, then the screen would look weird and some letters would be thin and some would be fat, as if they are trying to figure out what resolution should be adjusted to show the right images.



Brightness/Lumens

When we talk about seeing some clear displays, we also talk about having the clear brightness. The brightness can be increased and decreased. The measurement of brightness is done through the luminance. It is also measures as the candela that is per square meter. One might also find it as the CD/M2. If the brightness is increased, the number would also shoot up the better quality is the display would be seen. Also, the brightness can be measured using the lumens. Many digital projectors use this one and if a projector's display has around three thousand lumens, it would work great in a room having some dim light. If it is six thousand, then it would work perfectly in the very dim room and if the light coming from outside isn't covered that much.



Analog vs. Digital

The video signals that are sending to the display from the computers vary in their nature. There are the Analog signals which are mostly simple. The VGA display most likely send these simple and the continuous signals which are called the analoge signals. If the VGA display is pretty huge and it is plugged in, one would notice that it would take some time to get on. That's because we lose the signals. The Analog signals are lost during that time when they are being transited from the DE-15 interface of VGA that is installed on computers. Now, the modern monitors are having the digital signals. These signals are pretty much common in some HDMI interface since that can provide some really good output not only to the computers, but the TVs as well.



Privacy/Antiglare Filters

Filters are added to the displays by the people and they have become pretty common. Especially if the work is being carried out in some environment where security is some important issue, then one would like putting up the security filter. These filters are easily visible and can be seen easily whether they are installed in the PC or a laptop. But if one changes the angel of view, the screen turns into the black or the golden colour. Since the monitors today are pretty glossy, there is another filter used for this which is the antiglare filter. It helps preventing the ambient light block our visions by creating some images on the screen. So, the visuals become really clear and the work can be done easily using this filter.



Multiple Displays

If one is using a workstation, he might need more than one display so that the information can be seen all at once and it becomes easier for the user to work on it. One can put some various applications at the various places in the multiple screens. One can have the different things grouped up and shown on the other screens. Also, these displays can be used as the mirror as well and they can be shown to the other people who can know what one is doing on the computer.



Hence, knowing about the right monitor is very important since one might need the normal monitor but if he doesn't know what monitor to use, he might spend up lots of money on it. Another thing is, the location of the sure matters a lot as it is mentioned that at some places which are above the sea level, the displays may get distorted.


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