Patent ID: 6091680
Filing Date: 2000-07-18
Classification: G11B

Abstract:
A focus control apparatus for irradiating a light beam onto a recording surface formed in each of at least two layers of a recording medium, and generating a drive signal for a focus actuator for moving an optimized light convergence point of said light beam from one recording surface to the other, based on a focus error signal, said focus error signal being generated based on a returned light from said recording medium, said apparatus comprising:detecting means for determining that said focus error signal crosses a predetermined level to detect a specified level crossing;instruction means for generating a focus jump instruction;drive signal generating means for generating said drive signal in response to said focus jump instruction and for receiving an output from said detection means to recognize a timing for detecting a specified level crossing of said focus error signal upon receipt of said output, thereby extinguishing said drive signal in response to said timing; andinhibiting means for inhibiting the recognition of said timing by said drive signal generating means for a predetermined period in response to said focus jump instruction.