From cdrlabs.com......

Sony Japan has announced that they've developed a new optical head that is capable of reading and writing three formats: Blue-ray disc, DVD and CD.

Sony Corporation has developed a single 3-wavelength recording/playback optical head, capable of recording and playing-back 3 formats, Blu-ray Disc (BD), in addition to DVD, CD, which is a high-density optical disc system capable of recording/playing back high definition contents.

BD is an optical disc system capable of recording and playing-back HD contents from, for example, HD broadcasting. Sony has commercialized the world's first BD recorder with this standard. The BD market is expected to expand in the coming era where high-quality contents will become the mainstream and BD recognized as the indispensable optical disc system. On the other hand, together with the capability to recording/playing-back HD contents of the BD standards, it is desired for the BD recorder to play DVD software, recorded rewriteable/postscript DVD disc, as well as playback of music CD. In order to cope with this, in , 2 optical heads, one to playback DVD and CD, and the other to record and playback BD is incorporated.

In the newly developed 3-wavelength recording and playback optical head, the main characteristics are its capability to record/playback the 3 formats, BD, DVD and CD with one single optical head.This is achieved by the introduction of the newly developed single unit 3 wavelength laser, and also an object lens corresponding to the 3 wavelengths.

This is definitely a step in the right direction. With Sony's new optical head, companies will be able to develop Blu-ray devices that are backwards compatible with existing DVD and CD technology.