The companies that established the basic specifications for the Blu-ray Disc are: Hitachi Ltd., LG Electronics Inc., Matsushita Electric Industrial Co. Ltd., Pioneer Corp., Royal Philips Electronics, Samsung Electronics Co. Ltd., Sharp Corp., Sony Corp. and Thomson Multimedia.
By employing a short-wavelength blue-violet laser, the format successfully minimizes its beam spot size by making the numerical aperture on a field lens that converges the laser 0.85. In addition, by using a disc structure with a 0.1 mm optical transmittance protection layer, the Blu-ray Disc diminishes aberration caused by disc tilt.