Patent ID: 6097690
Filing Date: 2000-08-01
Classification: G11B

Abstract:
An optical pick-up comprising:a frame permitted to undergo movement with respect to a disc-shaped optical recording medium adapted so that the central portion thereof is held by a rotational operation mechanism, where said optical medium is caused to undergo rotational operation by the rotational operation mechanism in a direction to come into contact with the central portion of the disc-shaped optical recording medium or to move away therefrom in parallel to the principal surface portion of the disc-shaped optical recording medium;a first converging means disposed on the frame;a first light source disposed on the frame and adapted for allowing light beams to be incident to the first converging means;a first photo-detector disposed on the frame and adapted for detecting light beams emitted from the first light source to be converged onto a signal recording surface of the disc-shaped optical recording medium by the first converging means to allow the converged light beam to be reflected by the signal recording surface;a second converging means disposed on the frame;a second light source disposed on the frame for allowing light beams to be incident to the second converging means; anda second photo-detector disposed on the frame for detecting light beams obtained by allowing light beams emitted from the second light source to be converged onto the signal recording surface of the disc-shaped optical recording medium by the second converging means to allow the converged light beam to be reflected by the signal recording surface,wherein the first light source and the second light source emit light beams of wavelengths different from each other.