Intelligent skipping method

Abstract

The intelligent layer jump method is applied in reading out CD in a CD driver. The CD has central reference point, at least one first reflecting layer and one second reflecting layer. The first reflecting layer has several first tracks, and the second reflecting layer has several second tracks. The intelligent layer jump method includes: focusing the laser beam of the CD driver onto the s reflecting layer to form the first focus and obtain one starting position; comparing the starting position and the target position on the second reflecting layer to decide the layer jump and track seeking path of the focus; and shifting the focus from the starting position to the target position according to the set layer jump and track seeking path.

Description

technical field [0001] The present invention relates to an intelligent layer-jumping method, and in particular relates to an intelligent layer-jumping method applied to CD drives. Background technique [0002] With the increasing demand for high-capacity optical storage media, a digital versatile disc (Digital Versatile Disc, hereinafter referred to as a DVD disc) with more than two reflective layers has increasingly played an important role. Therefore, when reading a DVD disc, how to quickly and stably read the data on the disc to reduce the data access time (data access time) is a research topic that various manufacturers are devoting themselves to. [0003] An optical disc drive rotates a disc and moves an optical pick-up head in the radial direction of the disc, and then uses a laser beam to scan the reflective layer of the disc to access data. Please refer to FIG. 1 , which shows a schematic cross-sectional view of a conventional disk with double-layer reflective layer...

AI Technical Summary

Problems solved by technology

Therefore, it is very likely that the focus point 116 falls between the reflective layer 102 and the reflective layer 104 during layer jumping due to difficulty in focusing, or exceeds the top of the reflective layer 104 to cause focusing failure, which is detected by the optical pickup head at this time. The focus error signals are all 0

In this case, even the focus compensation technology may not help, and because the position of the objective lens 114 is often not known after the layer jump fails, the focusing procedure has to be restarted, resulting in a longer time for refocusing , reducing the efficiency of data access

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