Dell is switching to mercury-free LED screens to illuminate its laptops starting in mid-December. The move is aimed at making the computers softer on the environment and easier to recycle.

In a press release Dell said that LED displays consume 43 percent less energy than ones lit with traditional cold cathode fluorescent lamps. Starting in December the new screens will be featured on two-thirds of Dell's notebook sales, including the Latitude E models and two Precision mobile workstation models.

Dell said that LED backlit displays will be standard in at least 80 percent of the laptops it sells by the end of 2009 and in all its notebooks by the end of 2010.

HP also has begun selling optional LED-backlit screens on some of its laptop and tablet computers.  Apple says it will do it one day, maybe.