An Introduction to DVI

With almost every home now having a PC: and Plasma’s, LCD’s & Projectors finally becoming affordable to millions of people we are now entering a “New Era” of the Home Entertainment Market, whereby the demand is ever growing for High Definition viewing.

Of course, the common denominator for this is the AV Interconnect. Universally the Entertainment Industry has decided that Digital AV Interfacing is the way forward for their potential superior presentation compared to the customary analogue system.

Two suitable digital interfaces have come to the forefront: IEEE 1394 known as Firewire or iLink & Digital Visual Interface known as DVI.

DVI launched in 1999, it is a pure Digital Interface that transmit visual data from a source device to a display monitor (TV). By using this interface (DVI) there is no analogue - digital or digital – analogue conversion that needs to take place before, during or after transmission.

We are currently seeing more and more devices coming onto the home market with DVI interfaces mainly through the Screen market as DVI was originally intended for connecting PC’s to flat screen monitors.

Because of the high bandwidth it enables a single DVI link to handle the entire standard HDTV formats as well as computer formats as high as 1600 x 1200 (UXGA) at 60Hz. Even the top of the high-definition formats, 1080p/60 (1920 x 1080 at 60Hz progressive, is well within its capability.

DVI has two types of link – “single link”, which is the most common on the home entertainments market and the “dual link” for even faster transmission of data. Dual link will be more for the high-end professional/studio end.

There are three DVI formats: All of which are picture only.

DVI-D

DVI-D format is used for direct digital connections between a video source (i.e. DVD Player) and a digital Plasma, LCD or Projector. This provides a faster, higher quality image than with analogue, due to the nature of the digital format – eliminating any conversion between the playing and viewing device.

DVI-A

DVI-A format (High Resolution Analogue) is used to carry a DVI signal to an analogue display such as a CRT monitor or an HDTV. Although some signal quality is lost through the digital to analogue conversion, it still transmits a higher quality picture than standard VGA. This is not expected to be a very popular type of connector.

DVI-I

The best of both worlds. DVI-I format can be used to carry either a digital – to - digital signal or and analogue-to-analogue signal.

Note: It cannot convert: i.e. It cannot carry analogue – digital or vice versa.

Like any other format, the DVI digital and analogue formats are not interchangeable via their respective cables and will require some form of conversion box.

DVI Cables

DVI standard cables are limited to 5 metre lengths- however, boosters are being introduced and with solid soldering techniques and fibre optics it is possible to expand DVI transmission up to 500 metres for the professionals.

For conversion boxes available see Lektropacks Converters & Scalers.

Lektropacks DVI Cables can be found here.

Also see DVI - Digital Audio/Video Interconnectors & DVI Pinout Table.