Tuesday, September 15, 2009

Semiconductor laser to record a multi-layer Blu-ray Disc

Blue-violet semiconductor laser (wavelength - 405 nm), in the pulse mode having optical power 500 mW, established specialists Sharp. Novelty is designed for optical drives with recording function drives Blu-ray Disc (BD).

Above capacity is sufficient to record information at a speed of 8x for three-layer and four-layer media. In June, Japanese manufacturers started producing such laser power 320 mW.

To increase the power, we apply a new method of processing the verge of the resonator, which is usually in a semiconductor laser is protected by a dielectric film. Amorphous film dielectric absorbs light, causing loss of power and eventually - to the degradation of the laser. The new laser, until the formation of the dielectric film developers have formed another layer of crystal aluminum oxynitride (AION). It was grown by epitaxial growth so that the axis of the crystal growth of aluminum oxynitride and the main crystal coincide.

Serial production of the new product is not planned yet, because the specification of three-layer and four-layer Blu-ray media has not yet been adopted. However, according to the company, she is ready for mass production.

Source: http://techon.nikkeibp.co.jp/