This paper discusses the phenomena of feedthrough which is a result of the interaction of the tracking-error signal (TES) with the focus-error signal (FES) in optical disk systems using push-pull tracking in grooved media. A computer model is used to study the FES and the optical beams phase distribution and intensity along the optical path and describe its mechanism and cause. The astigmatic and obscuration methods are used for the analysis and show that when 45° astigmatism is present the astigmatic yields the largest FES feedthrough. The two causes investigated were the phase and amplitude distribution of the reflected beam at the exit pupil of the objective lens.
|Original language||English (US)|
|Number of pages||9|
|Publication status||Published - Jan 1 1994|
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics