光盘读写头光栅纵向和横向加工误差数值分析

Numerical Analysis for the Longitudinal and Transverse Error of Grating in the Optical Pick-up Head

基于标量衍射理论给出了矩形光栅衍射效率的一般表达式,数值分析了VCD、DVD和CD-ROM光盘读写头(光学头)分束光栅纵向和横向加工误差对辅助光束与读写主光束强度之比以及对透过率的影响。结果表明,对辅助光束与读写主光束强度之比,纵向加工误差与横向加工误差可以互补,但是,要以损失部分透过率为代价;对光学头分束光栅,其纵向加工误差与横向加工误差间存在的互补性,对光栅的具体制作有着实际的参考价值。

The effects of the longitudinal and transverse error of grating in the optical pick-up head of VCD, DVD,and CDROM during manufacturing on the transmittance and the ratio of intensity between the assistant and reading beam are analysed numerically by using the general expression of diffraction efficiency obtained from the scalar diffraction theory. The result shows that the longitudinal and transverse errors are compensable according to the assistant and reading beam, however, at the expense of transmittance loss. For grating in the optical pick-up head,the compensability between the longitudinal and transverse error practical references on the manufacture of grating.