20 years ago today, the CES in Las Vegas was buzzing with talk of Blu-ray technology, players, and media. Several years in the making, Blu-rays arrived with considerable industry backing, with “seven out of the eight major movie studios announced movie titles for the launch,” reports Blu-ray.com. This successor to the DVD offered improved density and thus capacity vs earlier optical formats, largely thanks to the development of blue‑violet laser diodes – hence the name.
Blu-ray discs boosted single layer media capacity to 25GB, vs 4.7GB for DVDs, using a new 405nm blue‑violet laser combined with more advanced materials. The shorter wavelength enabled a higher numerical aperture for more pits per sq mm. This was complemented by a tighter track pitch and a thinner (but harder) protection layer to boost capacity tenfold (comparing single-layer media).
