摘要
为了实现高密度存储,DVD盘片使用波长为650/635nm的激光且物镜NA应大于0.6。而CD则使用780nm的激光且数值孔径约为0.4。为了能与CD类光盘兼容,DVD播放器/驱动器中除了要有完成CD类盘片的解码电路外,其光学头也需能同时读取CD盘片。本文分析了目前已经实用的兼容CD的DVD光学头设计并比较了它们的优缺点。
In order to reach high density of storage, DVD adopts 635/650nm wavelength and more than 0.6 NA of objective lens. But the wavelength and NA of CD are 780nm and about 0.4 respectively. Beside the CD decoder circuit is needed, a DVD player/driver need a pick-up head capable to read CD, so that it can read both CD and DVD. In the paper, several designs of DVD pick-up head are discussed and compared.
出处
《光盘技术》
2000年第1期13-15,共3页
CD TECHNOLOGY
