Mitsubishi Electric Corporation

Yusuke Kanatake

Nobuo Takeshita

Tomo Kishigami

Yoshihiro Kiyose

Toshiya Matozaki

Kosuke Oda

Makoto Sakuwa

Koichi Ikuta

An object is to provide a thermal transfer printer having an inexpensive configuration and capable of making a tension given to an ink ribbon as constant as possible, even when a secular change and an environmental change occur in a DC motor used as a supply motor and a winding motor. A supply motor control unit controls a supply motor of an ink ribbon supply unit. A winding motor control unit controls a winding motor of an ink ribbon winding unit. A remaining amount detection unit detects a remaining amount of an ink ribbon. A variable calculation unit acquires parameters for an armature current, an applied voltage, and a rotational speed of each of the supply motor and the winding motor, and calculates variables to be used for controlling the supply motor and the winding motor on the basis of the acquired parameters.

Thermal transfer printer

A tracking control device includes a signal detector that detects a tracking error signal, and a crossing direction, a crossing period and a crossing velocity of an objective lens from a detection signal of an optical detector, a tracking drive signal generator that generates a tracking drive signal on the basis of the tracking error signal, a velocity-reduction drive signal generator that generates a velocity reduction drive signal for converging the crossing velocity into a vicinity of zero on the basis of the crossing direction and the crossing period, a loop switch, and a system controller that causes to executes velocity reduction driving for driving the objective lens actuator on the basis of the velocity reduction drive signal and that controls each of the members so as to switch from the velocity reduction driving to driving for driving the objective lens actuator on the basis of the tracking drive signal.

Tracking control device, tracking control method, and optical disc apparatus

An optical information processing method and apparatus performs a light irradiating and receiving step, a signal processing step, and an adjusting step of a spherical aberration and a focus offset on the basis of shift amount of first and second control devices and a performance evaluation value. The performance evaluation values for first, second, third and fourth points in an x and y coordinate system are detected, in which an x-coordinate is one of the shift amount of the first control device and the shift amount of the second control device and a y-coordinate is the other, the first point, second and third points having the same y-coordinate and different x-coordinates with each other, the fourth point being provided on a first straight line passing through the first point and being different from the first point.

Optical information processing method and optical information processing apparatus

An optical recording/reproduction method and device that can perform control for optimizing the amount of spherical aberration in a multilayered optical disc in a short period of time. When the objective lens is displaced in the focusing direction, the amplitude value of the focusing error signal detected just after leaving the focal position of a given first recording layer and the amplitude value of the focusing error signal detected just before passing through the focal position of a given second recording layer other than the first recording layer are measured with a particular spherical aberration, the amplitude ratio of amplitude values is calculated, the difference between spherical aberration and the optimal spherical aberration for the second recording layer is approximated as a function of the amplitude ratio, the optimal spherical aberration is calculated on the basis of this approximation, and the spherical aberration is set.

Optical recording/reproduction method and optical recording/reproduction device

According to a method for setting the laser beam power applied to reproduce information recorded on an optical disc, information recorded in a region on the optical disc is reproduced using three or more test reproduction powers (SB), the number of reproductions until the degradation of the quality of the reproduced signal reaches a prescribed value is determined as the degradation number of reproductions (SF), the relation between the test reproduction power and the degradation number of reproductions is approximated by a curve, and a reproduction power restricting the degradation of the reproduced signal quality to a predetermined amount or less over a certain guaranteed number of reproductions is determined (SF). In optical reproduction from an optical disc on which information is recorded, the optimum power of irradiation for reproduction can be set, and degradation of the information due to the reproducing light can be prevented.

Optical disc reproduction power setting method, optical disc reproduction method, and optical disc device

To adjust the parameters of a write strategy for recording data on an optical recording medium, the jitter value of a reproduced signal obtained from recorded data is detected. If the jitter value exceeds a prescribed threshold, a write strategy parameter having a comparatively small effect on the jitter value is adjusted, and subsequent data are written on the recording medium using the adjusted parameter. Parameters are selected for adjustment in ascending order of their effect on the jitter value. Stable data recording can thereby be carried out without significant jitter degradation.

Growing community of inventors

Tokyo, Japan

Yusuke Kanatake