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The future looks blue. And I’m very excited about it. By simply changing the color of a laser, the consumer electronics industry will finally have the next generation’s answer to VHS. We are going to enjoy a world of differences. Confused? Read on.

Whether the entertainment industry wants to admit it or not, high-definition television is definitely headed our way, and this calls for an entire new set of consumer electronics to facilitate this transition. The most obvious change will be in our televisions, which will need to support HDTV’s 720 and 1080 resolution formats (current television broadcasts are in the 250-300 range).

But where does this leave DVDs? The fastest growing consumer electronics device ever to hit the market is going to be left in the dust at a mere 500 lines of resolution. For the record, the higher the resolution, the more realistic and smooth the image will appear.

The reasonable conclusion to this dilemma is we need to start making DVDs that can offer HDTV-level resolutions … While we’re at it, let’s make these DVDs recordable and rewritable like old-fashioned VHS systems.

But it is not as simple as making DVD recorders that can record at higher resolutions. Higher resolution video requires more space to encode the same amount of video. This is analogous to how MP3s encoded at a higher bit rate sound better but require a bigger file size.

The solution to this conundrum is to go blue. Optical disc players read data stored on CDs and DVDs by shining a laser at microscopic pits that have been “burned” into the surface of the disc. As the laser strikes the series of pits on the bottom of the disc, the player interprets the nuances in the laser stream as bits of data. Suffice it to say that the two main components that determine a disc’s capacity are the laser and the pits.

DVDs have 4.7 gigabytes of data capacity compared to the 700-megabyte capacity of the CD. This means that DVDs have smaller pits on their surface and therefore can fit more information onto the same size disc. Smaller pits require a laser with a shorter wavelength to read the pits. Current DVD players employ an 800 nanometer red laser, but higher capacity DVD players will make use of a blue laser whose 405 nm wavelength can facilitate smaller pits and the larger amount of data necessary to encode HDTV video.

I know all this techno crap can be confusing, so I liken the situation to a highway. Increased traffic has required wider roads. But instead of making wider roads, automakers make thinner cars and thus allow more lanes to be crammed onto roads of the same width. 

Currently, there are two competing formats – Blu-Ray and Advanced Optical Disc – that will vie for widespread acceptance next year when the first blue laser DVD recorders hit the market. Blu-Ray DVD has the backing of nine major electronics manufacturers, including Sony and Matsushita (Panasonic), while Toshiba and NEC are backing Advanced Optical Disc (AOD) DVD.

Both formats are based on identical lasers, but Blu-Ray DVD was created on a clean slate, taking advantage of as many new manufacturing processes as possible, while AOD makes use of traditional DVD specifications for things like lens aperture and platter thickness. The result is that Blu-Ray DVDs will be offered in three capacities; 23.3, 25 and 27 gigabytes (depending on the quality and expense of materials used), while AOD DVDs will have a maximum capacity of only 20 gigabytes. But remember that 20 gigabytes is still more than four times the capacity of today’s 4.7 gigabyte DVDs.

The format war is a bit more complicated than just capacity, though. Blu-Ray was created outside of the auspices of the national DVD Forum (kind of like a United Nations of DVD manufacturers) with the reasoning that it is a next generation DVD system. In addition, Toshiba, which is backing the AOD format, is the chair of the DVD Forum, and argues that its format is more kind to the existing DVD infrastructure and will allow a lower price point.

The way things are shaping up, it looks like neither format backer is going to give in, and the DVD Forum might dissolve due to companies backing the “unapproved” Blu-Ray format. At the recent Ceatec Electronics Expo in Japan, most of the blue laser prototypes shown were Blu-Ray recorders, with only one AOD prototype offered by Toshiba.

I’ll sit back and enjoy the competition. May the best format win.