While the courts decide the legality of posting code that subverts DVD encryption, a Rhode Island company is on a mission to develop a new security method that will make discs self-destruct after a specified amount of time.

Less than a year after Circuit City put an end to its ill-fated Divx format, the proprietary pay-per-view DVD player, SpectraDisc is working on a self-destructing DVD technology that works with existing DVD players.

SpectraDisc, a spin-off from Spectra Science, a Providence, Rhode Island developer of laser technologies, is working on a special material to coat DVD discs, which start to self-destruct from the first moment of play. The coating is only around half a micron thick, around 1/200th of the thickness of a human hair. The thickness of the coating determines how long the disc lasts. The time limit can range from minutes to three days.

Spectra Science won't say exactly how its technology works, just that the chemical reaction is similar to how litmus paper works. Once the disc is put in the player and is hit by the DVD laser, it starts a process that eventually turns the disc blue, and blocks the DVD player's ability to read the disc.

Like Divx, it will be aimed at the renter market for people who want to simply rent and not worry about returning the disc. But SpectraDisc thinks it will avoid the disaster that was Divx.

"We think it gets around what killed Divx," said Nabil Lawandy, Specra Science's CEO. "There's no phone line, no credit card transaction, no special player needed, and no Big Brother element to it."

Digital Video Express, the joint effort between Circuit City and a Los Angeles entertainment law firm, launched the Divx format in September 1998 to almost universal criticism. Divx discs required a separate player that cost around $100 more than DVD players and needed a phone line hook-up, two facets that home theater enthusiasts hated.

Additional viewing of Divx discs could be purchased with a credit card, an element DVD owners abhored since it meant Circuit City would know an individual's viewing habits.

Lawandy estimates that time-limited DVD movies will sell $2.50 to $3 for two days of unlimited viewing.

A person can't buy more time, but at least SpectraDisc-coated discs will work with all existing DVD players, Lawandy said. "We think e-commerce will drive it because it's one-way. So long as it doesn't have to come back there's lots of ways to get it to you."

The discs could even be distributed in a paper sleeve similar to the way America Online sends out its membership discs, he said.

Lawandy said the discs will be offered in places like drug stores or Wal-Mart cash registers for impulse buys, but video rental chains may shy away since the discs don't allow the chance to charge late fees. Pizza parlors might even deliver movies along with the pies, Lawandy said.

"It's not the rental market that matters. The studios matter," said Lawandy. "If they feel that by proper timing this opens addition revenue, then they'll do it."

Spectra Science is pitching movie studios and DVD authoring houses. If Disney or another major studio gets behind the company, the time-limited discs could be available in six to nine months, according to Lawandy. If Spectra Science continues to go it alone, it will take up to 12 months to get a product out.

Lawandy said the coating technology could be applied to other optical discs. For example, music CDs are made from the same material but use a different laser wavelength, so adjusting the coating would be possible. Other possibilities for the coating are the Sony discs and CD-ROMs.

Good luck, says the webmaster of a popular DVD site.

"In light of Divx, I wonder how people will react to it," said Bill Hunt, who runs The Digital Bits, a site that was highly critical of Divx. "The studios will want it, but I think the public sent a message with Divx that they don't want to be limited like that. People don't like their access to media being controlled."

The founder of a DVD rental site is also skeptical, and not too thrilled at the idea of throwaway discs being proposed again.

"It's an environmental disaster to make all these plastic discs that degrade with all these chemicals," said Reed Hastings, CEO and chairman of Netflix.com, based in San Jose, California. "It's throwing an awful lot of technology at a problem."

NetFlix has to spend 33 cents for every disc to be returned, but Hastings thinks the extra cost of the coating might make it uneconomical. "It is nice to not return things, but you have to ask why didn't Divx work," he said. Divx discs rented for $4.49, and he doubts the new format could support $3 rentals. If studios support it and consumers want it, he said NetFlix will carry it.