Sony Corporation

Seiichi Sagara

Jumpei Kura

Naoyuki Nishigata

Atsushi Ishimaru

An optical disc apparatus includes: a light irradiation/reception section to irradiate an optical disc recording medium with light via an objective lens and receive return light of the light; a tilt adjustment section to tilt the lens; a focus servo control section to exert focus servo control over the lens; a focus bias application section to apply a focus bias to a focus servo loop; a tracking direction error signal generation section to generate a tracking direction error signal representing an error between light-reception signals; and a control section to perform a tilt adjustment value search process for making a search for a tilt adjustment value with which the tracking direction error signal is maximized, a tilt adjustment value revision process for revising the tilt adjustment value found by the tilt adjustment value search process, and an adjustment control process for causing the tilt adjustment section to perform tilt adjustment.

Optical disc apparatus, tilt correction method, and program

A recording and reproducing apparatus includes optical head means for writing and reading information expressed by a mark and a space on an optical recording medium by irradiating laser light to the optical recording medium, laser-drive pulse generating means for creating and supplying a laser-driving pulse in accordance with information to write to the optical head means and causing the optical head means to perform the irradiation of laser light for writing, mark edge error detecting means for detecting an error of the edge position of the mark from a signal read out from the optical recording medium by the optical head means; and adjustment control means for defining the adjustment on a laser-driving pulse generated by the laser-driving pulse generating means.

Recording and reproducing apparatus and laser-driving pulse adjusting method

A recording device including: an optical head section for irradiating a recording medium with laser to record and reproduce information; a laser driving section for driving the optical head section to output laser; and a control section for, in a process of adjusting recording laser power output from the optical head section, obtaining an evaluation value of a recorded area after a predetermined period of time elapsed since data was recorded as an evaluation value about a reproduction signal during reproduction of the recorded data, and adjusting recording laser power on the basis of the evaluation value after the predetermined period of time elapsed since data was recorded.

Recording device and method of adjusting laser power

A compensation value setting device selects, based on the first and second index values calculated by the first and second index value calculation sections for each combination of the spherical aberration compensation value and the lens' position compensation value, one combination of the spherical aberration compensation value and the lens' position compensation value and then sets the selected combination for correcting the spherical aberration and the position of the objective lens.

Compensation value setting device and compensation value setting method

A reproducing apparatus includes a head unit operable to direct a laser light beam onto a recording medium, the head unit having a focus servo mechanism and a spherical aberration correction mechanism for laser light; an evaluation signal generating unit operable to generate an evaluation signal serving as an index of quality of a reproduced signal; a focus servo unit operable to perform a focus servo operation by driving the focus servo mechanism in response to a focus error signal; a spherical aberration correction unit operable to perform spherical aberration correction by driving the spherical aberration correction mechanism in response to a spherical aberration correction value; a focus bias unit operable to add a focus bias to a focus loop containing the focus servo unit; and a control unit operable to control adjustment of a spherical aberration correction value and a focus bias value to be set in the spherical aberration correction unit and the focus bias unit, respectively.

Reproducing apparatus, and method of adjusting spherical aberration correction and focus bias

The present invention has been made to adequately and quickly adjust the spherical aberration and focus bias in an optical pickup. In the present invention, evaluation values are measured on a plurality of respective measurement points each determined by a combination of a spherical aberration correction value and focus bias value and a two-variable function having the spherical aberration correction value and focus bias value as variables is approximated to the evaluation values. Based on the two-variable function obtained by the approximation, the optimal value of the spherical aberration correction value and focus bias value on which the evaluation value becomes optimal is calculated. As a result, it is possible to adequately and quickly adjust the spherical aberration and focus bias in an optical pickup.

Growing community of inventors

Chiba, Japan

Seiichi Sagara