Objective lens optical part for optical pickup device and focusing method using the same

An objective lens optical part used to focus a light source to a data face and a track of an optical recording medium, the objective lens optical part comprising:

• a first optical member comprising a hollow portion with an opening, a lateral surface opposing the opening, and a circumference surface neighboring the lateral surface, wherein the lateral surface allows at least a light source to pass through;
• a second optical member arranged in the hollow portion for dividing the light source passing through the lateral surface into a first optical beam refracted toward the circumference surface and a second optical beam refracted toward a rim of the opening;
• two reflective members respectively arranged at lateral sides of the circumference surface for focusing the first optical beam toward the data face of the optical recording medium;
• and
• a tracking mechanism comprising a refractive member arranged between the second optical member and the optical recording medium, and a driving member connecting with the refractive member for focusing the second optical beam toward the track of the optical recording medium.