Plasma Display Working

A plasma display panel (PDP) is a type of flat panel display common to large TV displays (80 cm/30 in or larger). They are called "plasma" displays because the pixels rely on plasma cells, or what are in essence chambers more commonly

A plasma display panel (PDP) is a type of flat panel display common to large TV displays (80 cm/30 in or larger). They are called "plasma" displays because the pixels rely on plasma cells, or what are in essence chambers more commonly known as fluorescent lamps. A panel typically has millions of tiny cells in compartmentalized space between two panels of glass. These compartments, or "bulbs" or "cells", hold a mixture of noble gases and a minuscule amount of mercury. Just as in the fluorescent lamps over an office desk, when the mercury is vaporized and a voltage is applied across the cell, the gas in the cells form a plasma. With flow of electricity (electrons), some of the electrons strike mercury particles as the electrons move through the plasma, momentarily increasing the energy level of the molecule until the excess energy is shed. Mercury sheds the energy as ultraviolet (UV) photons. The UV photons then strike phosphor that is painted on the inside of the cell. When the UV photon strikes a phosphor molecule, it momentarily raises the energy level of an outer orbit electron in the phosphor molecule, moving the electron from a stable to an unstable state; the electron then sheds the excess energy as a photon at a lower energy level than UV light; the lower energy photons are mostly in the infrared range but about 40% are in the visible light range. Thus the input energy is shed as mostly heat (infrared) but also as visible light. Depending on the phosphors used, different colors of visible light can be achieved. Each pixel in a plasma display is made up of three cells comprising the primary colors of visible light. Varying the voltage of the signals to the cells thus allows different perceived colors.
Plasma displays should not be confused with liquid crystal displays (LCDs), another lightweight flat-screen display using very different technology. LCDs may use one or two large fluorescent lamps as a backlight source, but the different colors are controlled by LCD units, which in effect behave as gates that allow or block the passage of light from the backlight to red, green, or blue paint on the front of the LCD panel.

 

For the past 75 years, the vast majority of televisions have been built around the same technology: the cathode ray tube (CRT). In a CRT television, a gun fires a beam of electrons (negatively-charged particles) inside a large glass tube. The electrons excite phosphor atoms along the wide end of the tube (the screen), which causes the phosphor atoms to light up. The television image is produced by lighting up different areas of the phosphor coating with different colors at different intensities (see How Televisions Work for a detailed explanation).
Cathode ray tubes produce crisp, vibrant images, but they do have a serious drawback: They are bulky. In order to increase the screen width in a CRT set, you also have to increase the length of the tube (to give the scanning electron gun room to reach all parts of the screen). Consequently, any big-screen CRT television is going to weigh a ton and take up a sizable chunk of a room.
A new alternative has popped up on store shelves: the plasma flat panel display. These televisions have wide screens, comparable to the largest CRT sets, but they are only about 6 inches (15 cm) thick. In this article, we'll see how these sets do so much in such a small space.

Advantages

• Slim profile
• Can be wall mounted
• Less bulky than rear-projection televisions
• Produces deep blacks allowing for superior contrast ratio
• Wider viewing angles than those of LCD; images do not suffer from degradation at high angles unlike LCDs
• Less susceptible to reflection glare in bright rooms due to not needing backlighting
• Virtually no motion blur, thanks in large part to very high refresh rates and a faster response time, contributing to superior performance when displaying content with significant amounts of rapid motion

Disadvantages

• Heavier screen-door effect when compared to LCD or OLED based TVs
• Susceptible to screen burn-in and image retention, although most recent models have a pixel orbiter that moves the entire picture faster than is noticeable to the human eye, which reduces the effect of burn-in but does not prevent it. However, turning off individual pixels does counteract screen burn-in on modern plasma displays.
• Phosphors lose luminosity over time, resulting in gradual decline of absolute image brightness (newer models are less susceptible to this, having lifespans exceeding 100,000 hours, far longer than older CRT technology)
• Susceptible to "large area flicker"
• Generally do not come in smaller sizes than 37 inches
• Heavier than LCD due to the requirement of a glass screen to hold the gases
• Use more electricity, on average, than an LCD TV
• Do not work as well at high altitudes due to pressure differential between the gases inside the screen and the air pressure at altitude. It may cause a buzzing noise. Manufacturers rate their screens to indicate the altitude parameters.
• For those who wish to listen to AM radio, or are Amateur Radio operators (Hams) or Shortwave Listeners (SWL) , the Radio Frequency Interference (RFI) from these devices can be irritating or disabling.

How plasma displays work

A plasma display panel is an array of hundreds of thousands of small, luminous cells positioned between two plates of glass. Each cell is essentially a tiny neon lamp filled with rarefied neon, xenon, and other inert gases; the cells are luminous when they are electrified through "electrodes".
The long electrodes are stripes of electrically conducting material that also lie between the glass plates, in front of and behind the cells. The "address electrodes" sit behind the cells, along the rear glass plate, and can be opaque. The transparent display electrodes are mounted in front of the cell, along the front glass plate. As can be seen in the illustration, the electrodes are covered by an insulating protective layer. Control circuitry charges the electrodes that cross paths at a cell, creating a voltage difference between front and back. Some of the atoms in the gas of a cell then lose electrons and become ionized, which creates an electrically conducting plasma of atoms, free electrons, and ions. The collisions of the flowing electrons in the plasma with the inert gas atoms leads to light emission; such light-emitting plasmas are known as glow discharges.
In a monochrome plasma panel, the gas is usually mostly neon, and the color is the characteristic orange of a neon-filled lamp (or sign). Once a glow discharge has been initiated in a cell, it can be maintained by applying a low-level voltage between all the horizontal and vertical electrodes–even after the ionizing voltage is removed. To erase a cell all voltage is removed from a pair of electrodes. This type of panel has inherent memory. A small amount of nitrogen is added to the neon to increase hysteresis.

In color panels, the back of each cell is coated with a phosphor. The ultraviolet photons emitted by the plasma excite these phosphors, which give off visible light with colors determined by the phosphor materials. This aspect is comparable to fluorescent lamps and to the neon signs that use colored phosphors.
Every pixel is made up of three separate subpixel cells, each with different colored phosphors. One subpixel has a red light phosphor, one subpixel has a green light phosphor and one subpixel has a blue light phosphor. These colors blend together to create the overall color of the pixel, the same as a triad of a shadow mask CRT or color LCD. Plasma panels use pulse-width modulation (PWM) to control brightness: by varying the pulses of current flowing through the different cells thousands of times per second, the control system can increase or decrease the intensity of each subpixel color to create billions of different combinations of red, green and blue. In this way, the control system can produce most of the visible colors. Plasma displays use the same phosphors as CRTs, which accounts for the extremely accurate color reproduction when viewing television or computer video images (which use an RGB color system designed for CRT display technology).

 

What Does Liquid Crystal Display Mean

A liquid crystal display (LCD) is a thin, flat electronic visual display that uses the light modulating properties of liquid crystals (LCs). LCs do not emit light directly.

A liquid crystal display (LCD) is a thin, flat electronic visual display that uses the light modulating properties of liquid crystals (LCs). LCs do not emit light directly.

They are used in a wide range of applications, including computer monitors, television, instrument panels, aircraft cockpit displays, signage, etc. They are common in consumer devices such as video players, gaming devices, clocks, watches, calculators, and telephones. LCDs have displaced cathode ray tube (CRT) displays in most applications. They are usually more compact, lightweight, portable, less expensive, more reliable, and easier on the eyes.^{[citation needed]} They are available in a wider range of screen sizes than CRT and plasma displays, and since they do not use phosphors, they cannot suffer image burn-in.
LCDs are more energy efficient and offer safer disposal than CRTs. Its low electrical power consumption enables it to be used in battery-powered electronic equipment. It is an electronically-modulated optical device made up of any number of pixels filled with liquid crystals and arrayed in front of a light source (backlight) or reflector to produce images in colour or monochrome. The earliest discovery leading to the development of LCD technology, the discovery of liquid crystals, dates from 1888. By 2008, worldwide sales of televisions with LCD screens had surpassed the sale of CRT units.

How LCDs Work

You probably use items containing an LCD (liquid crystal display) every day. They are all around us -- in laptop computers, digital clocks and watches, microwave ovens, CD players and many other electronic devices. LCDs are common because they offer some real advantages over other display technologies. They are thinner and lighter and draw much less power than cathode ray tubes (CRTs), for example.
But just what are these things called liquid crystals? The name "liquid crystal" sounds like a contradiction. We think of a crystal as a solid material like quartz, usually as hard as rock, and a liquid is obviously different. How could any material combine the two?

We learned in school that there are three common states of matter: solid, liquid or gaseous. Solids act the way they do because their molecules always maintain their orientation and stay in the same position with respect to one another. The molecules in liquids are just the opposite: They can change their orientation and move anywhere in the liquid. But there are some substances that can exist in an odd state that is sort of like a liquid and sort of like a solid. When they are in this state, their molecules tend to maintain their orientation, like the molecules in a solid, but also move around to different positions, like the molecules in a liquid. This means that liquid crystals are neither a solid nor a liquid. That's how they ended up with their seemingly contradictory name.
So, do liquid crystals act like solids or liquids or something else? It turns out that liquid crystals are closer to a liquid state than a solid. It takes a fair amount of heat to change a suitable substance from a solid into a liquid crystal, and it only takes a little more heat to turn that same liquid crystal into a real liquid. This explains why liquid crystals are very sensitive to temperature and why they are used to make thermometers and mood rings. It also explains why a laptop computer display may act funny in cold weather or during a hot day at the beach.

Why People Scared of Linux?.. Fair discussion

 

Most of the people I know think Linux is very difficult for a layman to understand. They fear that after installing Linux they will not be able to do the normal tasks they do with Windows and thus they prefer paying money to Microsoft instead of even trying Linux.

Note: Before you read this Article I want to tell you that I am a big Linux fan and Linux being an open source Operating System is doing a Great Job.

Most of the people I know think Linux is very difficult for a layman to understand. They fear that after installing Linux they will not be able to do the normal tasks they do with Windows and thus they prefer paying money to Microsoft instead of even trying Linux.

There are lot of reasons behind this. Few reasons that I could figure out are:

1. Lack of Advertising about Linux compared to Windows. I understand that Linux is an open source product while Windows is Commercial but still I feel that there is lot of scope for advertising.

2. Lack of Awareness among the Retailers of Computers who advise the buyers to go for Windows instead of Linux. Some times its not just lack of awareness but also to gain more commission on the part of the retailer.

3. A very odd but a legitimate reason is that most of the time when people hear about linux is when a Geek is bragging about what he did on Linux last night and that layman will think “Man I don’t think Linux is for Guys like me!!”.

4. Most of the schools (atleast in India) teach their students Windows instead of Linux and thus the children when they grow up feel that windows is easy and safe to go with.

5. One reason for the Windows users not switching to Linux from Windows is that they are used to the working environment of Windows and So they are scared how they are going to do those regular task with Linux. Moreover there are many discouraging people around you who will be telling you stories of people who had to format their PC after installing Linux.

6. I also feel that the method of bring new versions every 6 months of different Linux distributions has many loopholes. First of all when a new release comes you are scared whether it is stable or not and whether his current apps will be compatible or not. So you wait for 1-2 months till you hear good reviews about it and just when you were about to feel that you got the one you can happily live with you hear about a new release which is better than that. Another reasons specially for Indian Users is that every time a new release comes out the user has to download it from net which is very time consuming considering the low internet speed in India.

7. The Last but the most important reason I feel why people don’t go for Linux is that the developers of Linux try to target more towards the technical guys instead of a normal user who is never going to code in his life. Linux only tries to compete with Windows in terms of a Better Development platform but it lags far behind from Windows in other areas. Though you may feel this reason to be invalid but this is what I feel.

I know a lot of Linux lovers will get hurt after reading this post and will be very angry at me but this is what is the harsh reality about Linux which can be changed if proper steps are taken by Linux.

Can you guys think of any other reasons? If so, I’d love it if you shared.

Note: The above written text are the author’s own views and they are not written to hurt the feelings of anybody

3 Amazing Firefox Hacks

 

What good is a browser unless you can tweak it, hack it and bend it to your will? No good at all. The more you can hack it, the better it is. And that means that Firefox must be a great browser as when ever you feel that you know everything

 

What good is a browser unless you can tweak it, hack it and bend it to your will? No good at all. The more you can hack it, the better it is. And that means that Firefox must be a great browser as when ever you feel that you know everything

about it you come across a bunch of hidden (and some not-so-secret) tips and tricks available that will crank Firefox up and pimp your browser. Make it faster, cooler, more efficient. So today I have come up with 3 amazing firefox tricks you might not be aware of.

1. Save Session For All Tabs Opened In Multiple Firefox Windows

If you are an ardent user of Firefox then you may be aware that when more than one firefox windows are opened up, in that case when you close a firefox window, it does ask me the option to save the session and exit, rather it ask to close all the tabs in that firefox window, but it wont save the tabs in other windows. So this way you could not save the session for multiple tabs opened in multiple firefox windows.

In such a case, there is only one option left to save the session for all the tabs opened in separate firefox windows by terminating firefox through task manager, here is how you do it.

Press Ctrl+Shift+Esc to quickly launch task manager, click the process tab and locate firefox.exe and right click selecting the exe and click End Process Tree.

Next time when you will open firefox it will open all the tabs in all the windows that were previously open.

2. Open & Log In to Multiple Accounts Gmail, Facebook, or Twitter Accounts In FireFox

Firefox extension CookiePie manages Firefox’s cookies—small bits of text stored on your computer that tell a site you’re logged in, for example—in such a way that you can log into the same site multiple times.

How to use it?

Just follow the steps given below:

• Install CookiePie Firefox Extension.
• Create a new tab or use an existing one.
• Open the context menu of the tab (i.e: Press the right mouse button over the tab) and select “Toggle On/Off CookiePie”.
• A cookiepie icon will appear over the tab.
• Go to a site (e.g.: http://www.gmail.com) and login into your account.
• Create another tab.
• Enable CookiePie on that tab too.
• Log in with another account on the same site.

3. Bypass Download Waiting Time On Rapidshare, Megaupload, zShare, Mediafire etc

SkipScreen is a really useful firefox  addon for lot of users who download  various types of files from the popular file and media sharing sites like Rapidshare, Megaupload, zShare, Mediafire, and more.

Most of these file sharing web sites have a annoying waiting time limit before a free user can start downloading the requested file. So, SkipScreen can be really useful in saving your time wasted seeing the download waiting time as it removes the screen of download waiting time from these media sharing sites.

SkipScreen monitors the pages where you see the download time and will get the content you want before the download waiting time completes.

Facebook & Identity: The Continued Push Toward Becoming Your One True Login

Facebook announced this weekend that it would begin offering third-party applications and websites a way to request that users share their "current address and mobile phone number." Simple enough, right?

Facebook announced this weekend that it would begin offering third-party applications and websites a way to request that users share their "current address and mobile phone number." Simple enough, right?

While Facebook says that the move is intended to make it easier for users to take their information with them across the Web, members of the data portability community argue that its yet another move by Facebook to lock users in. At the same time, the question of how Facebook handles these permission requests and whether or not it's clear to the end user is a point of contention that further calls into question how a user's online identity should be handled.
We asked some experts in the field and here's what they had to say.

Facebook: It's All About Portability

First, Malorie Lucich, a Facebook spokesperson, told us that the impetus for the change comes down to enabling users to bring their information with them, rather than forcing them to type in the same information wherever they go:

We want to make it easy for people to take the information they've entered into Facebook with them across the web. This new permission gives people the ability to control and share their mobile phone number and address with the websites and apps they want to use for more efficient experiences. As always, no information will be shared with an app or website until a user explicitly chooses to share it.

David Recordon, a senior open programs manager at Facebook and member of the OpenID Foundation, commented yesterday that the feature was intended to offer precisely this portability. "Given that I trust Kickstarter enough to give them my credit card information, I also trust giving them with my address," wrote Recordon. "Why should I need to type my address in again versus them being able to ask me for it?"
Other members of the data portability community, however, see things differently and call into question Facebook's methods of data sharing.

A Central Hub or Cog in the Machine?

"The problem is not that the user can (and must be able to) choose to access their data from Facebook on a 3rd party site," said Chris Saad, co-founder of the Data Portability Project and VP of strategy at Echo. "The problem is that Facebook has architected the whole thing from the beginning to be an exclusive hub and spoke relationship with them rather than a peer to peer relationship on the open web."
According to Saad, Facebook's intentions are simple - to get third-party sites and apps to rely entirely on Facebook for user information. "It's like giving a taster," he said. "Paying comes later."
Alana Joy, an independent digital strategist, agreed with Saad that Facebook was vying to be the central hub, rather than another cog in the machine.
"Facebook seems to be more concerned with positioning themselves as the official global 'people registry', harvesting users' information for profit," said Joy, "than they are about providing a safe place for individuals to share their lives with only those they choose to."
Of course, Facebook founder Mark Zuckerberg has said rather plainly that the company wants to push people's boundaries and expand the idea of public versus private. A key point that the company stands behind is that the user is given the opportunity to decide whether or not they share this information, both in privacy settings and in the permissions dialog.
"We introduced the granular data permissions model last April to make it clear to users exactly what information an app or website is requesting, allowing them to make more informed decisions about whether or not they want to proceed," said Lucich. "That being said, we're always looking into ways to make the platform user experience as positive and clear as possible."

With Third-Party Apps, It's All or Nothing

This sort of granularity isn't enough for Elias Bizannes, executive director of the Data Portability Project.
"Something bugs me about the Facebook connect privacy options," said Bizannes. "When you connect, you see what permissions you have to give, but you don't have an option there to deny individual permissions."
According to Facebook, apps should only be requesting information they absolutely need and therefore, were a user to deny access, the app wouldn't be able to function anyway.
"The reason why people can't pick and choose what data to share is because the app needs the requested information in order to perform its core services, such as photo access for a photo app and birthday date access for a calendar app. Developers are required to only request the information it needs to provide a customized experience," wrote Lucich. "Ultimately, it's up to the user whether or not he or she wants to grant an app access to their information."
Bizannes argues that the current model of permission forces users to blindly accept and allow the sharing of their information, "because they know if they click 'no' they don't get any access to the app."
"Users should have the ability to decide upfront what data they permit, not after the handshake has been made where both Facebook and the app developer take advantage of the fact most users don't know how to manage application privacy or revoke individual permissions," argued Bizannes. "Data Portability is about privacy-respecting interoperability and Facebook has failed in this regard."

On The Other Hand...

Inside Facebook's Josh Constine takes a more tempered approach to the whole thing, suggesting that instead of kowtowing to fear, Facebook should "instead push forward while minimizing negative outcomes by helping users make [a] more informed decision."
Constine's article echoes Recordon's sentiments, reminding the fearful that Facebook has been diligent in other instances and made sure that third-parties were dealt with appropriately when they mismanaged user information. The new feature may ask users for more in terms of personal information, but "there are many benefits to allowing developers to ask users for their contact information," writes Constine. "Mobile phone number access could power apps that act as up-to-the-minute communication hubs between groups of friends, allowing members to be notified by SMS when friends are nearby, want to plan an event, or upload new content. Home address access could let ecommerce sites pre-populate delivery details during checkout, leveling the playing field so smaller merchants can compete with established giants like Amazon that have already forced users to type in their address manually."
Saad argues that Facebook continually ups the ante without properly notifying its users.
"It's obvious that most users don't understand the bargain they're making - and that's mostly because Facebook keeps changing it," said Saad. "The same prompt that once granted some basic permissions for authentication now grants permission to your whole life."
Pete Warden, a big data guru who recently found himself on the wrong side of Facebook's line between public and private, says that a big result of this new feature will be for third-party sites and applications to figure out who you really are.
"The most interesting part of this change is the ability it gives companies to connect Facebook accounts with information from offline databases," said Warden. "There's a treasure-trove of marketing data available for every household in the US that they'll now be able to use to profile their Facebook users for everything from buying habits to income, children and pets."
According to Warden, this sort of data will help sites connect your activities to your real identity in ways that were previously not possible.
While the word "privacy" has been a sore point for Facebook over the past year, is it that Facebook is entirely cavalier with user information or is it just that its scale provides an easy target? Warden said that Facebook isn't much different from many other sites. "They're just behaving like the rest of the marketing world, the only difference is that they're under a lot more scrutiny than everyone else."

To Share or Not to Share?

In the end, does this come down to the simple question of whether or not you should ever share this information if you don't want it to be public? This is a solution that many users advocate. On the other hand, should users be petitioning for a more granular control over their information, wherein they can make more individual decisions over when and where they share what information? The fact that Facebook wants to be your one true login is no secret and the company will continue to push the boundaries in this realm. How will most users react?
"Most people won't care until they personally are victimized by it," predicted Alana Joy. "Like the gentleman whose profile picture was used in a Facebook ad for singles when he is a married professional with a family. [...] It really does illustrate just how Facebook can and will do whatever they want with whatever you post there."

Facebook Estimated To Collect Almost 5 Percent Of U.S. Online Ad Revenue

Facebook may be responsible for nearly a quarter of all display ads shown in the U.S., but it only collects about 5 percent of U.S. online ad revenues. An article in AdAge reports on new estimates from eMarketer which peg Facebook’s 2010

Facebook may be responsible for nearly a quarter of all display ads shown in the U.S., but it only collects about 5 percent of U.S. online ad revenues. An article in AdAge reports on new estimates from eMarketer which peg Facebook’s 2010 advertising revenues at $1.86 billion, with $1.21 billion of that coming from the U.S. That would give Facebook a 4.7 percent share of the estimated $25.8 billion total spent in the U.S. on online advertising last year.
Despite its already impressive financial might, Facebook could be doing a lot better. The gap between its share of display ad impressions and ad dollars shows how poorly Facebook is monetizing those ads, and suggests there is still a lot of room for improvement. Indeed, by 2012, eMarketer estimates Facebook’s U.S. ad revenues will more than double to $2.89 billion and it will account for nearly 9 percent of the U.S. online advertising pie.
Meanwhile, Facebook’s worldwide advertising revenues are expected to reach $5.74 billion by 2012. As a (sad) point of comparison, eMarketer estimates that MySpace’s worldwide ad revenues will decline from a high of $470 million in 2009 to $156 million in 2012.
Below is a table from AdAge showing the estimates for Facebook’s U.S. advertising revenues compared to total U.S. online ad spending:

Facebook Share of Total US Online Advertising Spending, 2009-2012 (billions and % of total)
	2009	2010	2011	2012
Facebook	$0.56	$1.21	$2.19	$2.87
Total US online advertising spending	$22.70	$25.80	$28.50	$32.60
Facebook % of total	2.4%	4.7%	7.7%	8.8%

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Unity 2D Speeds up Ubuntu's Unity Interface on Low-Powered Computers

 

Whether you've installed Ubuntu on an older computer or you're rocking a low-powered netbook with Ubuntu installed, Ubuntu's Unity interface can be a little sluggish. Unity 2D is a low-resource version of Unity designed for weaker systems.

 

Whether you've installed Ubuntu on an older computer or you're rocking a low-powered netbook with Ubuntu installed, Ubuntu's Unity interface can be a little sluggish. Unity 2D is a low-resource version of Unity designed for weaker systems.

Ubuntu Unity is one of the coolest new features of Ubuntu 10.10 Netbook Edition (and all editions of the upcoming 11.04), but if you find it lags a bit too much for your tastes, the low-resource Unity 2D should make you a bit happier. It's currently in the daily build stages, but apart from a small quirk or two (like the rearranging of dock icons being broken), I found that it runs significantly faster than the default Unity installation. The only real difference is a lack of 3D eye candy. You can install it in either Ubuntu 10.10 and 11.04 by running the following Terminal commands:

sudo add-apt-repository ppa:unity-2d-team/unity-2d-daily
sudo apt-get update
sudo apt-get install unity-qt-default-settings

This will add the PPA to your system and install the correct package. Afterwards, log out of Ubuntu and you'll find you can pick Unity Qt instead of the Ubuntu Desktop or Netbook edition when you log back in. If you've got a low powered computer, give it a go and let us know how you like it in the comments.

Unity 2D (Qt) Now Available in a PPA For Ubuntu 10.10 and 11.04 [Web Upd8 via Download Squad]