Posts Tagged ‘flat panel display’
Future of Wireless Diplays and Wireless Monitors
September 8th, 2008
Wireless Display / Wireless Monitor
DisplayLink’s Dennis Crespo, executive vice president of marketing and business development said: “This wireless technology allows the PC platform to move to the next generation of convenience and aesthetics. Computers haven’t done a lot to clean up the problem of interconnect for users, and this technology allows you to do that.” The technology behind wireless monitors was first introduced at the 2007 CES. The company will introduce a finished product at the 2008 show.
It seems like in modern computing circles, the trend is for everything to go wireless. Wireless peripherals, like keyboards and mice, are already the norm. Wireless internet, such as Wi-Fi, or wireless internet over mobile telephony networks are becoming increasingly common these days. So why haven’t we experienced wireless displays and monitors?There are a few reasons why this is the case. It all is linked around how much data is involved in the transmission, and what wireless technologies can cope with this large amount of data. It is potentially quite feasible to transmit low-quality displays over wireless technology.
However, since modern computing tends to focus around video, gaming, and other applications which require high-resolution displays, transmitting high-quality video pictures becomes problematic. How do we characterize a display as being low-quality, as opposed to high-quality? The way we do this is by determining what is the resolution of the display, ie., how many pixels are along the bottom side of the screen and how many pixels are along the left hand side of the screen. A common medium-resolution display consists of 1024 pixels along the left hand side of the screen, and 1280 pixels along the bottom of the screen. That works out to be 1,310,720 pixels making up the screen.
Don’t forget that your display that you’re looking at is a beautiful colour display. How much data you allocate to encode the color of each of the pixels determines how many colours you can display — often 24 bits of colour are used: 8 to determine the red, 8 for the green, and another 8 for the blue, mixed together in different proportion to display every color of the rainbow — just like with paint. And at the cinema, where each frame is displayed for only a fraction of a second, but played in quick succession, you get the illusion of movement, monitors do the same thing. The image changes every time you move your mouse, or a window, or do anything to change what is displayed on screen.
The way monitors work is to continuously refresh the display a number of times per second (often 60 times or higher), so that screen updates can look smooth and flicker-free. So we can work out the amount of raw data to display colorful 1280 by 1024 images, 60 times a second: 1,310,720 times 24 times 60. That’s about 1.75 gigabits per second — an astonishing speed. The most advanced form of home wireless, Wi-Fi 802.11n, supports a maximum of 300 megabits a second — much too short even if Wi-Fi is working perfectly.
Perhaps we can get away with using another wireless technology? Bluetooth, a common short-range wireless technology, famous for mobile phone headsets, currently only supports 3 megabits per second — not far by much! It seems rather impossible. The only other option is to compress the data before we send it over the wireless link, such as you would if you were taking a digital photograph and saving it as a JPEG to send to your friends over email. A digital photo as a JPEG is compressed in a lousy format, that is, the quality of the original image is lost to some extent in order to save space.
Clearly, that isn’t going to be acceptable for certain computer applications, such as games, or digital imagery. The only other option is to use “lossless” compression, where sophisticated algorithms are used to try and save space. But lossless compression takes a lot of computing power to do and doesn’t save as much space as lossy compression.
The amount of data to transmit quality images as you would normally see on a wired monitor is just too much for current wireless technologies to handle. Transmitting things over wires is much simpler, easier, and faster. Unless better compression technologies arise in the near future, or better wireless technologies are developed, it’s unlikely that we’ll see high-quality wireless displays any time soon.
A number of DisplayLink-enabled products are now available to buy from some of the world’s leading hardware manufacturers. Samsung SyncMaster 740N 17″ LCD Monitor, LG LX206WU, X-Rite Eye-One Display 2, 46″ 1080 Commercial Display, HP W1907 19″ Widescreen Flat Panel LCD, Enhanced USB Port Replicator, Samsung 2263DX, Samsung SyncMaster 940UX, I-O Data USB-RGB/D Adapter, Kensington Video, I-O Data USB-RGB Adapter, Sewell USB to DVI Adaptor (1280×1024), Gefen USB to DVI Graphics Adapter, Mobile Video Devices – usb2dvi, Videk USB to VGA & DVI Adaptors, Apple Cinema 23 HD Flat-Panel Display, Philips 10.2 inch Digital Photo Display Frame, RATOC Systems USB-DVI Adaptor