High-density optical disk apparatus focus searching method

Abstract

The invention relates to a method for searching focus of a high-density compact disc device, which can prevent an object lens and the compact disc from occurring conflict while a light picker is used to perform the focus searching operation for recognizing the disk by the compact disc. The focus searching method of the invention uses the object lens of the light picker to raise the high-density compact disc to the compact disc direction and judges whether a S-curve which is reflected with light by the surface of the compact disc is detected simultaneously when the power source of the high-density compact disc device is started. When the S-curve which is reflected with light by the surface of the compact disc is detected, the compact disc is judged to be mounted on the high-density compact disc device, and then the value of a revolving counter for counting the operation of raising the object lens is compared to a static critical value. Furthermore, when the counting value of the revolving counter is less than the static critical value, the operation of raising the object lens is maintained until the counting value of the revolving counter is equal to the static critical value. when the counting value is equal to the static critical value, the operation of raising the object lens is stopped.

Description

technical field [0001] The present invention relates to a focal length searching method of a high-density optical disc device, and particularly relates to a focal length search operation in which the objective lens of an optical pickup is rotated up / down to search for a focal length position in order to determine whether or not the optical disc and the optical disc are installed. A focal length search method of a high-density optical disc device in which an objective lens of an optical pickup collides with an optical disc. Background technique [0002] Recently, high-density discs that emphasize standardized operations, such as Blu-ray discs (Blu-ray discs), use a denser 405nm cyan-purple laser compared to DVDs that use existing 650nm wavelength red lasers. It is a disc with a diameter of 12cm such as a DVD that can store 27GB of data equivalent to 13 hours of SDTV-quality images and 2 hours of HDTV-quality images, so it will become a new generation of optical recording medi...

AI Technical Summary

Problems solved by technology

[0007] However, when using a high-density optical disc such as a Blu-ray Disc, since the working distance over which the objective lens (OL) can move is short, there is no danger of causing a collision between the objective lens and the optical disc when performing a search operation without additional control. very big

In this way, the objective lens of the optical disc or optical pickup will be damaged.

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