Sony has taken the wraps off the first video recorder that uses blue-laser technology.

The BDZ-S77 will go on sale in Japan next month. It is based on the Blu-ray optical disc format announced just over a year ago. The nine consumer electronics companies behind it are promoting it as a system for recording high-definition television broadcasts.

The companies came up with the format because DVDs cannot hold enough data to be suitable for high-definition video.

Blu-ray uses a blue laser to record data on discs, while CD and DVD systems use red lasers. Blue lasers have a shorter wavelength — 405 nanometers compared to around 650 nanometers on DVD systems — which means the laserbeam can be focused on to a smaller area of the disc surface. In turn, a smaller area is needed to store one bit of data and so more data can be stored on a disc.

Along with Sony, the format is backed by Hitachi, LG Electronics, Panasonic, Philips, Pioneer, Samsung, Sharp and Thomson Multimedia.

Sony's first generation recorder will land on Japanese retail shelves on 10 April at a price of ¥450,000 (£2,421). It looks similar to the prototype Blu-ray player that Sony showed at the Ceatec show last October.

To support the new machine, Sony also announced its first generation Blu-ray media. Discs with a 23GB capacity will go on sale from 10 April priced ¥3,500 (£19). There are three disc sizes specified in the initial Blu-ray format, and 23GB is the lowest capacity and easiest to make of the three. The other capacities are 25GB and 27GB.

Recordings are made in Mpeg-2 format, and the 23GB disc can store two hours of high-definition video at maximum quality, or four hours of standard-definition digital broadcasting. Up to 16 hours of lower-quality analogue terrestrial broadcasting can be stored.

Sony has no plans to launch the recorder overseas as yet.