光学头光束孔径匹配

Aperture matching in optical disk head

光学头是光盘存储器的核心部件，光学头光束孔径匹配是光学头设计的一个至关重要的问题。必须合理地确定光源的光束口径与光盘物镜孔径比值，才能保证其光能量耦合效率，并获得较小的光斑尺寸和合理的焦深。本文以衍射光学为基础，详尽地分析了光束孔径匹配对光能耦合效率、光斑尺寸、物镜焦深的影响。

Optical head is the core device of the optical disk drive. The aperture matching is the most important problems of optical head design. We must design the ratio of the source beam size and aperture of object lens reasonably to assure energy matching ratio (EMR) and to achieve smaller size of focus point and reasonable focus depth. Based on the diffraction optics, this paper analysis the effect of aperture matching on EMR, size of focus point and focus depth of the object in detail.